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In order to study the action of alcohol on the oral mucosa, Sprague-Dawley female rats, receiving an alcohol rich diet, were sacrifical as well as their controls, 98, 200 and 290 days after the experiment start and their oral mucosa studied histochemically and ultrastructurally. In the alcoholic animal, 1) the epithelium was thickened from day 98 on and SS and SH groups were detected in the keratin; 2) at this time interval, positive acid phosphatase areas were noted. Under the electron microscope, myelin figures were observed phosphatase areas were noted. Under the electron microscope, myelin figures were observed between cells on days 98 and 200. Cells undergoing autolysis could explain the lysosomial enzyme activity; 3) the DNA activity assessed by methyl-pyronine green stain was increased after 200 and 290 days. This activity was correlated at these time intervals with the increase of the mitosis number; 4) succinodeshydrogenase showed an increased activity on days 200 and 290. The mitochondria often of large size showed no ultrastructural changes even on day 290; 5) the vessels, already on day 98, then on days 200 and 290, showed a decrease in alkaline phosphatase reactivity with occasional thinnings of the wall. These modifications suggested that alcohol was able to modify the integrity of oral mucosa cells in the rat, perhaps by modifying the quality of the cell walls.

The risk of developing a tumor of the nervous system in humans is analysed in several studies of populations, exposed to ionising radiation for medical reasons, or exposed to military or occupational radiation. The main data come from series of patients who underwent radiotherapy during childhood: a high incidence of tumors of the nervous system is found after irradiation of one to a few grays as treatment of a benign disease (especially tinea capitis), as well as after irradiation at higher doses of a few tens of grays for the treatment of cancer (in particular cerebral irradiation in acute lymphoblastic leukaemia). The type of radiation-induced tumors is variable, but meningioma is more frequent after low doses and glioma and sarcoma after higher doses used in the treatment of neoplastic diseases. A dose-effect relationship appeared between the risk of tumor of the nervous system and the radiation dose. The risk was higher when radiation was delivered at a younger age. Much less data are available after radiotherapy in the adulthood, but an increased risk of cerebral tumor appears in the series of ankylosing spondylitis patients. As for the exposures to radiodiagnosis exams, the main problem is the risk of cerebral tumor in children whose mother has undergone abdominal or pelvic X-rays during pregnancy. No risk of neurologic tumor was found in the A-bomb survivors irradiated at Hiroshima and Nagasaki. Occupational exposure to ionising radiation has been incriminated in the first radiologists exposed to high doses. In nuclear industry workers, the results of epidemiological studies are contradictory and at the present time it is not possible to link their radiologic exposure with a risk of tumor of the nervous system. In populations living near nuclear plants, mortality due to tumors of the nervous system was not increased.

With over 70,000 patients treated worldwide, protontherapy has an evolution on their clinical applications and technological developments. The ballistic advantage of the Bragg peak gives the possibility of getting a high conformation of the dose distribution to the target volume. Protontherapy has accumulated a considerable experience in the management of selected rare malignancies such as uveal melanomas and base of the skull chordomas and chondrosarcomas. The growing interest for exploring new and more common conditions, such as prostate, lung, liver, ENT, breast carcinomas, as well as the implementation of large pediatric programs advocated by many experts has been challenged up to now by the limited access to operational proton facilities, and by the relatively slow pace of technical developments in terms of ion production, beam shaping and modelling, on-line verification etc. One challenge today is to deliver dynamic techniques with intensity modulation in clinical facilities as a standard treatment. We concentrate in this paper on the evolution of clinical indications as well as the potentialities of new technological concepts on ion production, such as dielectric walls and laser-plasma interactions. While these concepts could sooner or later translate into prototypes of highly compact equipments that would make easier the implantation of cost-effective hospital-based facilities, the feasibility of their clinical use must still be proved.

Acute alcohol ingestion can induce drug interactions, either pharmacokinetic or pharmacodynamic. Metabolically, they especially result from interference in the enzymatic systems which catalyse ethanol oxidation, the blocking of alcohol dehydrogenase, blocking of the microsomal oxidation system of ethanol with accumulation of the xenobiotic and risk of overdose, and blocking of acetaldehyde dehydrogenase with an antabuse effect. Pharmacodynamically, the main interactions result from the action of drugs having a sedative effect, such as tranquilizers but also antidepressants, neuroleptics, analgesics, H1 antihistamines, central antihypertensive drugs (CNS depressant?), etc. This sedative effect is increased by ethanol, which can be dangerous in at-risk situations.

Blood ethanol measurement can be performed by gas chromatography if the samples are diluted before tungstate-sulfuric acid deproteinization. A good knowledge of linearity area is needed for to obtain with this method the same results than with the oxydimetric method.

Epidemiological studies have shown the role of alcohol in esophageal cancer in the West of France. Experiments were undertaken on Wistar rats to study the effect of locally consumed alcoholic beverages on the esophagus. Neither histological modifications, precancerous lesions nor cancer were observed in the animals. There was no significant excess of benign or malignant tumours in treated animals when compared with controls.