Induction of hydrocephalus in mice by i.c. inoculation with a streptococcus isolated in mice following passage of multiple sclerosis brain material.

Following the intracerebral passage in 1-day-old mice of brain material from multiple sclerosis (MS) patients hydrocephalus was produced. An organism, identified as a Streptococcus, was isolated from the hydrocephalic brains. When grown in pure culture the Streptococcus was capable of producing gross hydrocephalus in 1-day-old mice by destruction of the ependyma and blockage of the aqueduct. The organism cannot be allotted to any known streptococcal species nor can it be said at this stage that it is related to MS. The failure to detect bacteria in the original MS brains by bacteriological culture methods makes its origin open to question.

Further studies of macrophages in relationship to avirulent Semliki Forest virus infections.

The amount of virus in macrophages from normal mice infected in vivo and in vitro with avirulent Semliki Forest Virus A7(74)C1 and virulent L10/C1 has been compared to that in macrophages infected similarly from mice given Myocrisin (colloidal gold) before inoculation. Very high titres of virus were found in all macrophages which had been "blockaded" with Myocrisin up to 10(8.5)/ICLD50/ml with the avirulent strain and up to 10(7.2)/ICLD50/ml with the virulent strain. "Blockade" of the macrophages in this way made the normally avirulent strain virulent. The possible reasons for this are discussed.

Treatment of malignant ascitic and pleural effusion with Corynebacterium parvum.

Six patients with malignant effusions, five from adenocarcinomas and one from a melanoma, were treated by intrapleural or intraperitoneal Corynebacterium parvum. In each case there was a definite reduction in the effusions with a significant decrease in the number of malignant cells; in most cases the effusions stopped completely. Although none of the patients lived for more than a year after treatment, they were undoubtedly more comfortable, as they no longer required frequent paracentesis. In some cases the patients lived for longer than originally expected in a state in which the quality of life was acceptable.

Enhanced resistance of mice to infection with Langat (TP21) virus following pre-treatment with Sindbis or Semliki forest virus.

Significant protection to heterologous i.c. challenge with the flavovirus Langat occurred after a single i.c. injection of avirulent strains of the alpha viruses Semliki Forest or Sindbis given 1 day to 5 weeks before challenge. Some protection also occurred after an i.p. infection with these viruses. We consider that the protection afforded by the alpha viruses is due to interference with the multiplication of Langat virus and is related to the maximum level of brain infectivity reached in the alpha virus infection.

Acromegaly caused by pulmonary carcinoid tumours.

Two patients are described whose acromegaly was cured by removal of a bronchial carcinoid tumour. One had an enlarged pituitary fossa and evidence is presented that in this patient the tumour was not secreting growth hormone. The evidence available suggests that the tumour was producing a growth hormone releasing substance. It is suggested that some cases of the pluriglandular syndrome may be secondary to small bronchial carcinoid tumours that produce substances as yet unidentified, that stimulate the growth and hyperactivity of other endocrine tissue.

Effect of an inapparent viral encephalitis on the levels of lysosomal glycosidases in mouse brain.

The changes in the activity of several lysosomal glycosidases of mouse brain which occured during an inapparent infection with the A774 strain (avirulent) of Semliki Forest Virus (SFV) have been related to the histopathological and viral changes caused by the disease. N-acetyl-beta-D-glucosaminidase, N-acetyl-beta-D-galactosaminidase and beta-glucuronidase were significantly elevated between post-inoculation day 7 and 28. Lesions characteristic of encephalitis were also observed between these times. Histochemical and biochemical of encephalitis were also observed between these times. Histochemical and biochemical observations showed that not all areas of brain were affected equally; the cerebellum, parts of the mid-brain and the spinal cord showed the most sevre biochemical and histochemical changes, whilst histopathological lesions were more evenly distributed. The biochemical results have been related to the histological, histochemical and virological findings and the production of glycosidases from 2 or more cellcular types has been postulated.

An electron-microscopic study of the development of virulent and avirulent strains of Semliki forest virus in mouse brain.

Two strains of Semliki Forest Virus (SFV), the avirulent and virulent, were used to study the development of virus in both baby and adult mouse brain. The development of SFV in the brain was similar in baby and adult brain using the virulent strain and in the baby mouse brain using the avirulent strain. Mature virus could not be found in adult mouse brain using the avirulent strain. This paper shows that extracellular virus particles near the cell membrane stimulate the formation of coated vesicles and thus absorption of virus particles by the cell. It is suggested that these coated vesicles with contained virus particles are stimulated to develop nucleoid cores on their membrane forming cytopathic vacuoles, Type II (CPV-II). Excessive membrane growth takes place and the membrane of the CPV-II with the nucleoid cores invaginates to form intravacuolar tubules. It is suggested that these tubules become responsible fro the formation of mature virus particles. Thus the membrane of the CPV-II appears to be responsible for the development of both the inner core and outer coat of the virus.