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We propose an optical pickup that acquires data from both layers of a dual-layer digital versatile disk simultaneously. An adaptive optical element that uses liquid crystals creates two axial foci separated by a spacing of 55 mum, which is the distance between the two layers. The spacing between the foci can be varied by the adaptive element. The separation of the reflected light into TE and TM polarized light, corresponding to each of the layers, is made by dielectric gratings that are characterized by high aspect ratios. Electron-beam lithography and reactive ion etching techniques were used to produce the submicrometer structures. All fabricated elements were assembled in a pickup system, whose properties were measured.

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Intestinal toxicity exerted by indomethacin was compared to that induced by copper-indomethacinate, free or associated to zwitterionic phospholipids. A single high dose of indomethacin (15 or 20 mg/kg), copper-indomethacinate (15 or 20 mg/kg), or copper-indomethacinate liposomes or nanocapsules (15 mg/kg) was orally administered. Then 24 hr later jejunoileal tissue was taken for macroscopic observation, ex vivo nitrite production, and determination of myeloperoxydase and iNOS activities. Antiinflammatory activity of the drugs was investigated using the carrageenan-induced paw edema model. Indomethacin induced penetrating ulcerations of the intestine that were maximal at hour 24. Copper-indomethacinate induced significantly less ulceration than indomethacin with no significant difference in MPO and iNOS activities. The injurious action of indomethacin on the small intestine was further reduced when copper-indomethacinate was administered as the phospholipid-associated state while similar anti-inflammatory action was observed on rat paw edema. The antiulcerogen effect of copper-indomethacinate seems to be linked to its free radical scavenging effect without any modification of nitric oxide release.

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Two ternary copper(ll) complexes of indomethacin [1-(4-chlorobenzoyl)-5-methoxy-2- methyl-1-H-indole-3-acetic acid] called hereafter lndo, were prepared and characterized by single crystal X-ray diffraction. The first complex Cu(2)(Indo)(4)(DMF)(2) I crystallizes in space group P-1 (a = 10.829(2), b = 13.379(2), c = 16.491(3) A; alpha = 105.58(2), beta = 101.06(2), gamma = 106.96(2) degrees ; V= 2104.6(6) A(3), Z= 1). The title molecule is a centrosymmetric binuclear complex, with Cu atoms bridged by the carboxylate moieties of four indomethacinate ligands. The four nearest O atoms around each Cu atom form a square planar arrangement with the square pyramidal coordination completed by the O atom of N,N'-dimethylformamide. Daily administration for seven days of 1 mg/kg of indomethacin, I and I encapsulated into liposomes induces a weak inflammation of rat gastrointestinal tract. I was less inflammatory than indomethacin but the better protection was brought by encapsulation of the compound. This might be of interest in sustained therapies of chronic inflammatory diseases.

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Human leukocyte elastase is present in large amounts in the crevicular fluid of patients with periodontal disease and was considered as a putative biological marker of the evolution of such diseases. The aim of this work was to measure spectrophotometrically amounts of active elastase (AE) and elastase complexed to alpha 1 proteinase inhibitor (E-alpha 1-PI) in gingival crevicular fluid obtained, from patients suffering from rapidly progressive periodontitis (RPP group) or adult periodontitis (AP group) with different probing depths (3 to 5 mm and > 6 mm). AE and E-alpha 1-PI concentrations were negligible in healthy individuals. AE, but not E-alpha 1-PI, concentration appears to vary significantly with the probing depth in patients suffering either from rapidly progressive or adult periodontitis. No correlations were found between levels of AE and E-alpha 1-PI in the different groups of patients. AE concentration seems to be a marker of periodontal diseases in relation with probing depth.

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An animal (rat) model of gingival injury ("impaction") induced a gingival inflammatory reaction, which was characterized by a breakdown of gingival collagen and the elastic network, as well as a significant increase of gingival elastase. The present study was conducted to investigate whether ceramides, sphingolipids composed of sphingosine N-acyl-linked to fatty acids, a chemical structure with antielastase properties, could counteract the development of such an inflammatory process. The ceramides used in these experimental series were extracted from wheat and characterized. The main fatty acids were 16:0, 18:1, 18:2, and the sphingoid moiety was phytosphingosine. Inhibition of elastase by ceramides was demonstrated in vitro and the concentration necessary to inhibit 50% of elastase activity was 41 mg/l using the synthetic substrate methoxysuccinyl-alanine-alanine-proline-valine-p-nitroanilide (MeOSuc-AlaAlaProValpNA). However, this anti-elastase activity was not observed in vivo in our animal model of gingival inflammation. A glycosaminoglycan (Heparin), recognized as a potent inhibitor of elastase, was entrapped in ceramides. A local treatment of impacted gingivae by encapsulated heparin led to a dose-related decrease of the elastase level in gingival extracts. Encapsulation in ceramides potentiated the effect exerted by heparin alone. This inhibitory effect of encapsulated heparin on elastase suggested a vector effect of these amphipathic molecules.

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Synopsis Ceramides, composed of sphingosine N-acyl linked to fatty acids have become widely used in cosmetology. They play several physiological roles in the regulation of skin barrier function. Human neutrophil elastase (HNE) can be inhibited by long-chain fatty acids and their derivatives; it was therefore postulated that plant ceramides could be inhibitors of HNE. Ceramides were extracted from wheat, isolated and characterized. The main fatty acids were 16:0, 18:1, 18:2 and the sphingoid moiety was phytosphingosine. Concentrations necessary to reach 50% inhibition of HNE were, respectively, 33 and 41 mug ml(-1) for non-glycosyl ceramides (CER) and glycosyl ceramides (gly-CER) when using a synthetic specific substrate. Similar extents of inhibition were obtained using a physiological substrate, insoluble elastin. Ex vivo studies showed that CER protected human skin elastic fibres against HNE degradation. Ceramides, being natural non-toxic substances, besides their role in cosmetics, could be of pharmacological interest in dermal inflammatory disorders.

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A model of gingival inflammation was performed in Sprague-Dawley rats weighing 180-200 g. Mechanical bamboo stick-induced injury was inflammatory when bacteria contaminated the sticks. Bacteria were first obtained from gingival fluid collected from a patient with adult periodontitis. Another strain from Institut Pasteur (IP 6444) induced similar inflammation. Inflammation was then quantified 10 days later by means of elastase assays performed in gingival extracts. In parallel, elastic structures were observed and elastic fibers were quantified by automated image analysis. This technique of "impaction" was able to induce a gingival inflammatory reaction characterized by a significant increase of gingival elastase content, infiltration of gingival tissues by elicited cells, and gingival elastic fiber breakdown. These parameters were correlated, and measurement of one of them might be useful for pharmacological studies applied to the treatment of periodontal lesions. An example of results obtained from animals treated by heparine was shown.

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In rain-fed cereal-producing areas of Morocco, stubble and straw from barley and wheat and forage grazed from fallow lands are important feeds for sheep. Supplementation to maintain BW of ewes pregnant while grazing stubble, methods to improve utilization of straw, annual forage legumes to complement grazing of fallow land, and by-product feeds in diets for weaned lambs have been tested in collaborative research trials. Pregnant ewes grazing cereal stubble for 10 to 12 wk at a modest stocking rate and unsupplemented, or at a heavier stocking rate and supplemented after 5 wk, gained about 3 kg; most of the gain occurred in wk 1 to 4 due to intake of residual scattered grain. Following the stubble-grazing period (coincident with late gestation), straw plus an energy supplement alone resulted in low lamb birth weight and survivability. Urea treatment increased N content of straw and holds potential. After the onset of winter rains, self-reseeding annual legume (Medicago spp.) pastures allowed lactating Timahdit ewes to gain 4 kg during 90 d postpartum. Their suckling lambs gained 260 g/d, thus doubling the weight of lamb weaned per ewe compared with those grazing unimproved fallow. Confined growing lambs fed diets with 40% sugarbeet pulp or 20% carob meal gained more than 200 g/d, reducing the time needed to reach market weight. These results demonstrate that marked improvements in performance and efficiency of sheep in Mediterranean rain-fed cereal/livestock systems are possible using locally available resources.

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