Pathogenicity of a vaccine strain of vaccina virus in rabbits administered by intravenous route

The pathogenicity of the Lister (Elstree) strain, a vaccinia virus, in rabbits after intravenous injection was studied by histopathological and immunofluorescent methods. Inoculation of 1 X 10(7) PFU (pock-forming unit) virus into weanling and young adult rabbits caused severe emaciation and high mortality within 2 weeks. Pathological findings were characterized by vesicular lesions along muco-cutaneous junction areas of the eyes, nose and mouth and by inflammatory changes in the brain, mainly in the meninges and choroid plexus. Immunofluorescent staining of the tissues of animals sacrificed at intervals demonstrated the accumulation of vaccinia viral antigen (s) in the loci of pathological changes. The suitability of this model system for the study of pathogenesis of human postvaccinal meningoencephalitis is discussed.

Herpes simplex encephalitis: an autopsy case with isolation of type 1 herpes simplex virus

An adult case of herpes simplex encephalitis was studied after autopsy. Postmortem examination revealed necrotizing encephalitis associated with Cowdry type A intranuclear inclusion bodies in glial cells. Herper simplex virus type 1 was isolated from the removed brain. Herpes simplex virus antigens were detected diffusely in wide areas of the brain by immunofluorescent test and viral particles characteristic to herpes simplex virus were demonstrated by electron microscopy. There was an apparent discrepancy between severity of histological changes and distribution of virus antigen.

Comparative studies of several vaccinia virus strains by intrathalamic inoculation into cynomolgus monkeys

From the comparative studies of the virulence of several vaccinia virus strains by intrathalamic inoculation into cynomolgus monkeys, the following results were observed. The CV1 virus was most virulent, the New York City Board of Health, Ikeda, EM63, and Lister viruses were slightly less virulent, and DIs and LC16 viruses least virulent. The characteristic findings were widespread inflammatory lesions in the meninges and choroid plexus which were closely associated with the replication of vaccinia virus, and parenchymal lesions which might be referred to a encephalopathy in the deceased monkeys. Meningoencephalitis was, however, ofter recognized in the monkeys sacrificed at 14 days postinoculation and those dying late.

Demonstration of vaccinia virus antigen in brains of postvaccinal encephalitis cases

Five lethal cases of postovaccinal encephalitis (PVE) were examined in attempts to detect the viral antigen by the fluorescent antibody techniques and to isolate the infectious vaccinia virus. Histologically, the brain tissues were characterized by meningoencephalitis, with perivascular infiltrations and inflammatous reactions mainly in leptomininx, chroid plexus and ependyma. By direct immunofluorescence staining, vaccinia virus antigen was found in the brain specimens of one case, but not in the other four cases. The existence of antigen-antibody complexes was suggested by the deposition of immunoglobulins in the brain specimens. After treatment with 3 M NaSCN solution to dissociate the immunoglobulins from the complex, the viral antigen was demonstrated in specimens of two cases. Localization of viral antigen(s) thus detected coincided with that of meningoencephalitic reactions in the histological examination. Virus isolation on chick embryo chorioallantoic membrane was negative in all cases. Participation of viral pathogenicity in the etiology of PVE is discussed.

Effect of common protective antigen vaccination to protect mink from challenge exposure with Pseudomonas aeruginosa

The protein portion of endotoxin (OEP), or common antigen of Pseudomonas aeruginosa prepared from strain N10 of P aeruginosa, was examined as a possible vaccine against this organism in mink. Mink were given OEP vaccine and challenge exposed by instillation with the inoculum into the nostril. They survived after this exposure with 4 median lethal (LD50) doses of strain NC-5 (protease negative, elastase negative) or with 160 LD50 doses of strain 5 (protease positive, elastase positive). Strain NC-5 belonged to TYPE 5 AND strain 5 belonged to type 8 (according to the serotyping method of Homma). Strain N10, the source of OEP, belonged to serotype 5. Thus, the mink vaccinated with OEP vaccine were able to stand challenge exposure to both homologous and heterologous serotype strains. More mink given OEP vaccine survived the challenge exposure by intranasal spraying with virulent strain 5 than did those in the nonvaccinated control group, with a significant difference. When the surviving mink of the vaccinated group were rechallenge exposed with 300 or 3,000 LD50 doses of the same strain a month later, most of them survived.

Vertical transmission of type I and type 2 Herpes simplex virus infection in hamsters

The relation of type 2 herpes simplex virus infection during the several stages of embryogenesis of hamster was examined using histopathological and immunofluorescent techniques. The comparative investigation between type 2 and type 1 was done. Both types of herpes simplex virus caused placental lesions and vertical transmission in fetuses when the virus was inoculated intravenously into pregnant hamsters at the middle and late stage of gestation.

Diffuse interstitial fibrosing pneumonitis and adenovirus infection

With electron microscopy, adenovirus particles, which were almost round, variable in density, and 60-80 mmu in diameter, were observed in the nuclei of type II alveolar epithelial cells, infiltrated plasma cells and alveolar macrophages of a man with chronic interstitial fibrosing pneumonitis. The immunofluorescent technique also suggested adenovirus infection.

Studies on tocopherol derivatives: V. Intestinal absorption of several d,1-3,4-3H2-alpha-tocopheryl esters in the rat

Twelve d,1-3,4-3H2-alpha-tocopheryl esters were synthesized from d,1-3,4-3H2-alpha-tocopherol. They were acetate, propionate, butyrate, isobutyrate, caprylate, palmitate, acid succinate, benzoate, nicotinate, o-hydroxybenzoate, o-acetoxybenzoate, and pivalate. The hydrolysis of these esters with bile-pancreatic juice and with 9,000 x g supernatant of small intestine and liver homogenates of rats was examined. When these esters were incubated in small intestine or liver supernatants, hydrolysis occurred at a similar rate. In the incubation experiments, alpha-tocopheryl acetate, propionate, butyrate, isobutyrate, caprylate, palmitate, and acid succinate were classified as an easily hydrolyzable group. Alpha-tocopheryl benzoate and nicotinate were in a moderately hydrolyzable group. O-hydroxybenzoate and pivalate, which resisted hydrolysis, were in a scarcely hydrolyzable group. O-acetoxybenzoate was easily hydrolyzed to the o-hydroxybenzoate. Hydrolysis on straight chain fatty acid esters of alpha-tocopherol easily occurred in bile-pancreatic juice. In in vivo experiments, the lymphatic absorption rate of 6 esters, acetate, palmitate, acid succinate, nicotinate, o-hydroxybenzoate, and pivalate, was measured on thoracic duct fistula rats. Easily hydrolyzable esters were recovered mostly in lymph as alpha-tocopherol, whereas, an ester which strongly resisted hydrolysis, such as pivalate, appeared mainly unchanged. This fact suggested that hydrolysis of alpha-tocopheryl esters was not necessarily a prerequisite for intestinal absorption. The percentage of absorption of slowly hydrolyzed esters in lymph was relatively lower than that of moderately or easily hydrolyzable esters.

Effects of protease and elastase from Pseudomonas aeruginosa on skin

Protease and elastase were inoculated intracutaneously in rabbits, the process of which was followed. Of the enzymes, 50 mug caused circumscribed hemorrhage at the inoculated local and subcutaneous part, and ulcerating lesions of skin and extensive hemorrhagic lesion at the subcutaneous tissues were observed in the case of inoculation with 250 mug. The doses amounting to 500 to 1000 mug of the enzymes caused extensively ulcerating, necrotic lesions at the skin and extensive hemorrhage at the subcutaneous tissue, and a large amount of hemorrhage was observed in the abdomen. It was observed microscopically that cellular infiltration and hemorrhage in the subcutaneous tissue and muscular layer were caused by administration of 2 to 10 mug of the enzymes, and that degeneration of endothelial cells was caused by 2 mug of them.

In vivo studies on protease and elastase from Pseudomonas aeruginosa

Protease and elastase from Pseudomonas aeruginosa were inoculated in female mice by intravenous, intraperitoneal, intrapleural and intranasal route, and the lethality and damage of various organs were examined. The protease and elastase exhibited respectively the following minimum lethal dose (MLD) values in 24 hr; 300 and 375 mug inoculated intravenously; 200 and 125-250 mug intraperitoneally; and 100 and 62.5 mug intrapleurally. The instillation of a defined dose of the enzyme by the intranasal route was difficult to control, therefore the MLD could not be defined exactly. The protease and elastase were capable of eliciting hemorrhage at various organs of mice according to the route of inoculation. Of protease, intravenous injections elicited petechial hemorrhage at the lungs and parietal bone-area, and severe one in the medullary area of kidney. The intraperitoneal injection resulted in petechial hemorrhage of the lungs, diaphragm, peritoneum and gastrointestinal serosa. Intrapleural injections and intranasal instillation resulted in confluent pulmonary hemorrhage. Of elastase, intravenous injections elicited confluent pulmonary hemorrhage, hemorrhage in the medullary area of kidney and cerebral ventricles, and petechial hemorrhage at the stomach-walls. The intraperitoneal injections resulted in petechial hemorrhage at the lungs, diaphragm, peritoneum and gastointestinal serosa. Intrapleural injections resulted in confluent pulmonary hemorrhage, and petechiae at the diaphragm and pleura. Intranasal instillation resulted in confluent pulmonary hemorrhage.