We have recently isolated an apparently novel retrovirus (LM7) from a patient with multiple sclerosis (MS). We present here results showing that (1) LM7 retrovirus can be transmitted in vitro to a normal human leptomeningeal cell culture and that (2) specific antibody against this retroviral strain can be detected in MS cases. Our results suggest that, if this virus is an endogenous retrovirus, it is different from human endogenous elements already described.

Antibodies, Viral↗

PubMedDate not supplied

Results of an ultrastructural study comparing stria vascularis with organ of Corti in guinea pigs treated with kanamycin.

Ultrastructural study of ototoxicity is well documented with two points of interest: organ of Corti for aminoglycosides and stria vascularis for loop diuretics. As a previous study suggested initial lesions of stria vascularis, an attempt of comparison and of chronological study was made between the organ of Corti and stria vascularis lesions by kanamycin intoxication. The method was devised by J. M. ARAN, with electrophysiological control. We failed to find in the stria vascularis a radial or longitudinal pattern of lesions. We could not discern a chronological injury between the organ of Corti and stria vascularis because both were damaged even in the less deafened animals. Nevertheless, two facts were clarified: hair cell lesions are lysosomial as for the kidney lesions, while stria vascularis lesions are mitochondrial, melanine granulations play a part in drug metabolism (increased number, secretory aspect) and deserve further study.

Animals↗

PubMedDate not supplied

Melanine value in the stria vascularis of pigmented guinea-pigs treated by kanamycin.

In a previous report, kanamycin (400 mg/kg/d) seemed to increase the number of melanine granulations in intermediate cells of the stria vascularis, especially in the second and third turns. To precise these data, melanine was studied in those turns by ultrastructural morphometry in a control group with 12 animals. We observed a large intra-individual and inter-individual variation before intoxication. Thus, the meaning of melanine modifications by kanamycin must be carefully evaluated.

Animals↗

PubMedDate not supplied

Ultrastructural changes associated with peripheral neuropathy in HIV/AIDS.

Light and electron microscopic studies were performed on neuromuscular biopsy specimens from 12 neurologically affected seropositive patients, 7 with the acquired immune deficiency syndrome (AIDS), 2 with AIDS-related complex, and 3 with no symptoms except for neuropathy. All patients had an axonal injury associated or unassociated with demyelination and peripheral neurogenic atrophy. Capillary lesions were consistently present, which seems to be a new finding. Moreover, tubuloreticular inclusions (TRIs) were found in endomysial (9 of 12 cases) and endoneurial (7 of 12 cases) vessels. Statistical analysis showed that TRIs in more than 20% of endomysial vessels correlated with a survival time shorter than 12 months (P = 0.028). Thus the quantification of TRIs seems to be one of the vital prognostic elements in this patient population.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

[Ultrastructural localization of the oxydasic activity in Toxoplasma gondii (author's transl)].

Toxoplasma belonging on the RH strain were studied under a transmission electron microscope. The activities looked for were: peroxidase, cytochrome oxydase and acid phosphatase. An oxydasic cytochrome respiratory activity was seen. It is localised on the crests and on the peripheral membrane of the mitochondria of Toxoplasma gondii. In the given experimental conditions, no such activity appeared in the other intracytoplasmic organels of the parasite, nor in the vacuoles of the host-cells containing living toxoplasma but the organels of those host-cells presented an oxydasic activity.

Acid Phosphatase↗