[Pathologic characteristics of the most frequent peripheral nerve tumors]. / Aspects histopathologiques des principales tumeurs des nerfs périphériques.

Benign tumors of the peripheral nerves come from ectodermic tissues. This chapter describes the most common forms: the schwannomas and the neurofibromas. Schwannomas have two possible patterns of cells: Antoni A and B types. Neurofibromas are most often associated with neurofibromatosis NF1 and may be localized, diffuse, or plexiform. The benign tumor structures account for the fact that they can be removed with or without preserving the concerned nerve. Malignant tumors (malignant peripheral sheath tumors) come from degeneration of neurofibromas in two out of three cases and have a poor prognosis.

Magnesium and cardiac arrhythmias: nutrient or drug?

The antiarrhythmic potency of Mg has been described repeatedly since 1935, both as a factor in human disease and in animal experiments. Nevertheless, this therapeutic efficacy is rarely mentioned in textbooks. Both the pharmacological effect of Mg and the correction of Mg deficiency have been used in treatment of digitalis toxicity, variant angina, Torsades de Pointes, as well as in arrhythmia of unknown origin. Mg-deficiency can be caused by malabsorption or by excessive urinary loss. Both situations can occur on a congenital basis. The most frequent cause is probably alcoholism. Iatrogenic factors include digitalis, diuretics, gentamicin, as well as cisplatinum, which appreciably enhance urinary Mg loss. Correction of Mg-deficiency by parental and/or oral administration should lead to recovery. If the cause of the deficiency can be eliminated, once the deficit is repaired it may be acceptable to discontinue the supplement. However, the cause is often multifactorial, requiring further evaluation and treatment.

Sexual disturbances arising from multiple sclerosis.

Multiple sclerosis patients under the age of 50 with only a slight handicap were very often found to have disturbances of sexual functions (among male patients 71.4%; among female patients 73.9%; control group 18.7%). In 19.6% of the cases, the disturbances were of a serious nature. These disturbances, as well as disturbances of function of bladder and colon, were found to be mainly brought about by separate damage in the lumbosacral region of the spinal cord. The incidence of these disturbances bore no relationship to the degree of motor disturbances, age of the patient or duration of the disease.