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Several types of hereditary retinal degeneration with progressive alteration of photoreceptors exist in men and animals. Recent immunohistochemical results have shown strong degradation of transferrin, the protein responsible for iron transport, in retinas of rats with hereditary retinal degeneration. Freeze-dried thin sections of rat retinas from different stages of the disease, and respective coeval control sections, have been analyzed using nuclear microprobe. In this first part of the study, the rat retinas at post-natal stages of 35 and 45 days have been analyzed. The sample preparation and the post-irradiation staining to determine precisely the retinal layers involved are described. Preliminary results of element distributions (K, Ca, Fe) in the rat retina layers are discussed. A very high content of calcium in the choriocapillaris of dystrophic rat retinas was observed. Preliminary results on iron distribution in the rat retina layers are presented.

Resume Le deces de patients VIH-positifs de cause cardiaque n'est pas exceptionnel. L'etiologie des myocardiopathies dilatees associees au sida est souvent inconnue, meme a l'autopsie. Nous rapportons une observation associee a une carence majeure en selenium. Ce patient, seropositif pour le VIH depuis 4 ans presente une pneumocystose pulmonaire puis une cryptococcose neuromeningee. Deux mois plus tard il est hospitalise pour une pancreatite alors qu'il est en etat de grande denutrition. Il presente alors un etat de defaillance cardiaque globale entrainant le deces. Aucun agent pathogene n'est mis en evidence dans le myocarde a la necropsie, mais le taux plasmatique de selenium est effondre a 24 μg/L. Le deficit en selenium a ete associe a une myocardiopathie dilatee en dehors du sida (maladie de Keshan). Les patients VIH-positifs voient une baisse precoce de leur taux plasmatique de selenium, celui-ci pouvant etre effondre chez des patients denutris. La carence en selenium pourrait expliquer un certain nombre des myocardiopathies dilatees associees au sida, et la supplementation en selenium pourrait etre utile chez ces patients.

BACKGROUND Peripartum cardiomyopathy is a frequent condition of unknown origin in Sahelian West Africa. OBJECTIVE To identify the nutritional and trace-elements status, plasma concentrations of albumin, pre-albumin (trans-thyretin), retinol binding protein, copper, selenium and zinc were assayed in 35 African women living in a Sahelian area, hospitalized in the Hopital national, Niamey (Republic of Niger) with peripartum cardiac failure due to peripartum cardiomyopathy. METHODS Plasma albumin was assayed by an automatic method; pre-albumin and retinol binding protein by radial immunodiffusion (Mancini's method); and plasma copper, selenium and zinc by neutron activation and particle-induced X-ray emission. The results were compared with those for a control group of African women living under the same conditions but without peripartum cardiac failure. RESULTS Plasma albumin and pre-albumin were lower in patients with peripartum cardiomyopathy than they were in controls (P < 0.001). For retinol binding protein, the difference was not statistically significant. The plasma concentrations of selenium and zinc were lower in patients than they were in controls (48 +/- 25 versus 77 +/- 16 ng/ml and 0.90 +/- 0.21 versus 1.17 +/- 0.25 micrograms/ml, respectively, P < 0.001) whereas that of copper was higher (2.03 +/- 0.37 versus 1.23 +/- 0.20 micrograms/ml, P < 0.001). The mean zinc: copper ratio was lower in patients than it was in controls (0.44 versus 0.95). CONCLUSION Such differences may be aetiological factors or biological consequences of the peripartum cardiac failure due to cardiomyopathy. Nutritional abnormalities may play a role in the pathophysiology of the disease.

Recently published results of the cooperative studies executed by the Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences (IPCE RAS), Research Center Vallée du Rhone (CEA, France), Institute of Nuclear Physics Orsay and University Bordeaux I [Centre Nationale de Recherches Scientifiques (CNRS), France] are reviewed. The review includes data obtained for the first time on the electrochemical properties and anodic dissolution of uranium monocarbide considered among possible bases of the fuel for the reactors of the IVth generation. The results of the investigations in the field of the synthesis of tetraalkyl ammonium pertechnetates, their physicochemical properties and thermal decomposition with formation of Tc metal and Tc monocarbide are summarized. The electrochemical reactions with participation of Tc ions in various oxidation states and their application in the nuclear fuel cycle are described. The behavior of technetium in natural waters near the locations of the radwastes long-term storage and in the areas surrounding nuclear power plants in RF and France was studied.

A specific selenium deficiency is a risk factor for Keshan disease, an endemic cardiomyopathy observed in China. In a Sahelian area of Niger, plasma selenium concentration was measured by neutronic activation and particle induced X-ray emission in 35 black African women with peripartum cardiomyopathy and 36 breast-feeding women without cardiac failure as controls. The plasma selenium concentration in patients was lower (48 +/- 25 ng/ml, mean +/- standard deviation) than in controls (77 +/- 16 ng/ml) (P less than 0.0001). Moreover, 40% (14/35) patients with peripartum cardiomyopathy had very low plasma selenium concentrations, below 45 ng/ml, versus none in controls. A low plasma selenium concentration is a risk factor for the Sahelian peripartum cardiomyopathy.

We prospectively studied plasma lipids in 95 HIV infected patients: we found that triglycerids increased, and cholesterol, HDL-cholesterol and apoA1 decreased only in patients below 50 CD4 lymphocytes/mm 3 . Lp(a) was high in all groups (mean level > 0,35 g/l). Lp(a) and TNF were significantly higher in patients with active opportunistic infection.

We have measured TNF-α and interferonα in 95 HIV positive patients and 20 healthy subjects. TNF-α was higher in the HIV+ patients ( P = 0.0001) and was correlated to the CD4 cell count ( P = 0.02) and cholesterol (negatively) ( P = 0.04). Interferon-α was correlated to the wasting syndrome ( P = 0.002), hypertriglyceridemia ( P = 0.004) and haematocrit ( P = 0.04).

Plasma selenium concentration was measured by neutronic activation and particle induced X-ray Emission in 35 Black African women with peripartum cardiomyopathy and 36 breast-feeding women without cardiac failure as controls. The plasma selenium concentration in patients was lower (48 ± 25 mg/ml) than in controls (77 ± 16 mg/ml) (P

Proton induced X-ray emission (PIXE) analysis, following enrichment by APDC-MIBK extraction, is used to measure chromium concentration in blood plasma from patients submitted to selective coronary artery cineangiography. The yield of the chromium preconcentration is determined with carrier-free 51Cr. From the catheterism results the patients are classified into three populations: coronary artery disease (CAD), heart disease (HD) and normal arteries (N). The first two groups, CAD and HD, have significantly lower chromium concentrations than does the group with normally patent arteries. The present analytical method and the results obtained provide an interesting contribution to the difficult problem of chromium determination in biological media.

Plasma chromium concentrations have been determined for 150 patients. These were subjected to coronary artery cineangiography and thereby divided into three groups: group CAD (those with coronary artery disease), group HD (those with heart disease, but no CAD) and group N (those with no CAD and no HD). Weighted, average chromium levels for these groups were 1.05, 1.72, and 8.51 ng/mL, respectively. The distributions of plasma chromium levels for the three groups suggest that an upper limit for plasma chromium may be established (6 ng/mL in this work) beyond which CAD may be considered to be extremely unlikely, thus eliminating the need for a certain number of cineangiographic examinations.

Depressive states are associated with various clinical or biochemical anomalies, some of which are considered to be signs or indicators ot depression (Extein et al. 1981: Harrison et al. 1984). Several studies have suggested that vanadium may play an important role in depresalve states by regulating the activny of the ubiquitous enzyme. Na-K-ATPasc. thereby directly affecting the activity of the membrane sodium pumps at either the peripheral level (Naylor and Smith 198 I) or the brain (Robinson 198 I ). The amount of work that has been carried out on the subject of vanadium and depressive illness has undoubtedly been limited by the major technical difficulties involved in the measurement of small concentrations of vanadium in bioloplcal media. as the values obtained are strongly dependent on the method employed. In this preliminary study. wc attempted to determine whether or not differences in serum vanadium levels could be detected in patients suffering from various forms of depression compared with normal subjects. The vanadium determinations were carried out at P. Siie Labo

Recent measurements have demonstrated that plasma chromium levels in patients with coronary artery disease are very much lower than in normal subjects. A review of the literature concerning the physiological functions of chromium (or GTF) shows it to be implicated in most of the known factors of cardiovascular risk, via its effect on insulin levels and activities. Chromium deficiency leads to impaired lipid and glucide metabolism and results in high circulating insulin levels, the probable consequences of which suggest that chromium deficiency may be a primary risk factor in cardiovascular disease.

The metallic implants studied are of endo-osseous type. We determined the composition of two types of implants on identical samples, before and after implantation in the maxilla or the mandible, the implants gave rise to serious rejection phenomena. We used the PIXE method (particle induced X-ray emission) for these analyses.