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This open, controlled study evaluated the effects of 6 month supplementation with Pycnogenol® maritime pine bark extract on health risk factors in subjects with metabolic syndrome. Pycnogenol® was used with the aim of improving risk factors associated with metabolic syndrome, central obesity, elevated triglycerides (TG), low HDL cholesterol, high blood pressure and fasting blood glucose. Sixty-four subjects (range 45-55 years) presenting with all five risk factors of metabolic syndrome were included, and Pycnogenol® was administered for 6 months. A group of 66 equivalent subjects were followed up as controls. In the 6-month study Pycnogenol® supplementation 150 mg/day decreased waist circumference, TG levels, blood pressure and increased the HDL cholesterol levels in subjects. Pycnogenol lowered fasting glucose from baseline 123 ± 8.6 mg/dl to 106.4 ± 5.3 after 3 months and to 105.3 ± 2.5 at the end of the study (p < 0.05 vs controls). Men's waist circumference decreased with Pycnogenol from 106.2 ± 2.2 cm to 98.8 ± 2.3 cm and to 98.3 ± 2.1 after 3 and 6 months. Women's waist decreased from 90.9 ± 1.6 cm to 84.6 ± 2.1 cm and to 83.6 ± 2.2 cm after 3 and 6 months. Both genders waist circumference reduction was significant as compared to controls at both time points. In addition, plasma free radicals decrease in the Pycnogenol group was more effective than in the control group (-34.6%; p < 0.05). In conclusion, this study indicates a role for Pycnogenol® for improving health risk factors in subjects with metabolic syndrome.

Most antioxidants show contradictory behaviors because in the biological environment, for unpredictable reasons, they can become prooxidants. Recently, a new simple method to monitor oxidative stress in serum was developed. This test detects the derivatives of reactive oxygen metabolites (D-Roms). Hydroperoxides are converted into radicals that oxidize N,N-diethyl-para-phenylendiamine and that can be detected through spectrophotometric procedures as U.CARR. (Carratelli units). One U.CARR. corresponds to 0.8 mg/L hydrogen peroxide. In normal subjects U.CARR. values range from 250 to 300. Values outside this range indicate a modification of the prooxidant/antioxidant ratio. On the basis of this method, we tested three different formulas of antioxidants (F1, F2, F3) in 14 apparently healthy volunteers (11 men and 3 women). Formula 1 was composed of 5 mg zinc, 48 microg selenium, 400 microg vitamin A (as retinol acetate), 50 microg beta-carotene, 15 mg vitamin E (as dl-alpha-tocopheryl acetate) and 10 mg L-cysteine. Formula 2 was composed of 30 mg bioflavonoids from citrus, 30 mg vitamin C (as L-ascorbic acid), 10 mg coenzyme Q(10) and 1 mg vitamin B-6 (as pyridoxine hydrochloride). Formula 3 was composed of Formula 1 plus Formula 2. Each formula was prepared in dry capsules (formulation D1, D2, D3) or in a fluid form (formulation P1, P2, P3). Each formulation was administered for 1 wk in a crossover design. A 15% deviation of U.CARR. levels was chosen as the cut-off value for a significant change in oxidative stress. Formulas F1 and F3 reduced mean U.CARR. levels in most of the treated subjects (t test, P < 0.05), whereas F2 was not active. Fluid formulations were more active than dry formulations (chi(2) test, P < 0.05). In some cases, a slight increase in oxidative stress was detected. These minimal increases were not related to any particular antioxidant formula. In one subject only, the administration of the dry formulation (D1), increased oxidative stress to a level that reached the cut-off value. In conclusion, when antioxidants are taken in combination at low dosages they reduce oxidative stress, and little relevant prooxidant activity is detectable.

High resolution (0.04 cm−1) FTIR spectroscopy is applied to monoclinic Er3+-doped BaY2F8 single crystals in the wavenumber range 500—24000 cm−1 and temperature range 9—300 K to study the crystal field splitting of the fundamental 4I15/2 and of the excited 4I13/2, 4I11/2, 4I9/2, 4F9/2, 4S3/2, 2H11/2, 4F7/2, 4F5/2, and 4F3/2 states and the effects caused by increasing Er3+-concentrations (2—20% m.f.), such as inhomogeneous line-broadening and new lines due to Er3+−Er3+ interaction. In the framework of the electron-phonon interaction, the thermally induced line-broadening and -shift are detected and accounted for by the two-phonon Raman model and the vibronic replicas of a few lines are investigated.

In view of the realization of high efficiency four-junction solar cells, InGaP layers, lattice matched to InGaAs, and (001) 6° off Ge substrate are grown by low pressure MOCVD at growth temperatures as low as 500 °C. The grown samples are undoped, p-type (doped by Zn) and n-type (doped by Te) materials with thickness around 1 μm. The ternary compound composition and structural properties are analysed by High Resolution X-Ray Diffraction and Transmission Electron Microscopy (TEM). Completely disordered InGaP layers are obtained with a target energy gap above 1.88 eV and a controlled Zn concentration around 10 17 cm -3 . The interface properties are studied by High Resolution TEM. A nanometric scale waviness is observed at the interface between InGaP and InGaAs and it is correlated to the step bunching of the substrate offcut. In addition to this, HRTEM shows a 2-3 nanometer thin layer originated by atomic interdiffusion between the As- and the P- based compounds. The difference in composition of this interdiffusion layer is demonstrated by depth resolved Cathodoluminescence (CL), which reveals - approaching the InGaP/InGaAs interface, a blue shift of the InGaP related peak and the appearance of a new CL emission band ascribed to a quaternary InGaAsP compound.