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X-ray Diffraction has been fully exploited as a probe to investigate crystalline materials. However, very little research has been carried out to unveil its potentialities towards amorphous materials. In this work, we demonstrated the capabilities of Grazing Incidence X-ray Diffraction (GIXRD) as a simple and fast tool to obtain quantitative information about the composition of amorphous mixed oxides. In particular, we evidenced that low angle scattering features, associated with local structure parameters, show a significant trend as a function of the oxide composition. This evolution can be quantified by interpolating GIXRD data with a linear combination of basic analytical functions, making it possible to build up GIXRD peak-sample composition calibration curves. As a case study, the present method was demonstrated on Ta 2 O 5 -SiO 2 amorphous films deposited by RF-magnetron sputtering. GIXRD results were validated by independent measurement of the oxide composition using Rutherford Backscattering Spectrometry (RBS). These materials are attracting interest in different industrial sectors and, in particular, in photovoltaics as anti-reflection coatings. Eventually, the optical properties measured by spectroscopic ellipsometry were correlated to the chemical composition of the film. The obtained results highlighted not only a correlation between diffraction features and the composition of amorphous films but also revealed a simple and fast strategy to characterize amorphous thin oxides of industrial interest.

We have deposited Ge, SiGe, SiGeSn, AlAs, GaAs, InGaP and InGaAs based structures in the same metalorganic vapor phase epitaxy (MOVPE) growth chamber, in order to study the effect of the cross influence between groups IV and III-V elements on the growth rate, background doping and morphology. It is shown that by adopting an innovative design of the MOVPE growth chamber and proper growth condition, the IV elements growth rate penalization due to As "carry over" can be eliminated and the background doping level in both IV and III-V semiconductors can be drastically reduced. In the temperature range 748-888 K, Ge and SiGe morphologies do not degrade when the semiconductors are grown in a III-V-contaminated MOVPE growth chamber. Critical morphology aspects have been identified for SiGeSn and III-Vs, when the MOVPE deposition takes place, respectively, in a As or Sn-contaminated MOVPE growth chamber. III-Vs morphologies are influenced by substrate type and orientation. The results are promising in view of the monolithic integration of group-IV with III-V compounds in multi-junction solar cells.

Background: Today, Brazil is the second country of the world in number of transplants. Nonetheless, waiting lists are getting longer. This lack of organs occurs mostly because of people's reduced knowledge about the donation process. With the aim of changing this scenario, in 2013 and 2014, "Organ Donation Week" events were held at the Federal University of Health Sciences of Porto Alegre., Methods: During the 2 years, documentaries followed by a cycle of debates with experts in this area were exhibited. In 2013, a "flash-mob" took place, with the purpose of performing a "transplant waiting list" around the perimeter of Santa Casa's Hospital Complex. In 2014, a morning full of educational activities was planned for the pediatric patients from the Santo Antônio Children's Hospital and their relatives., Results: It is estimated that approximately 1774 people were directly reached by the projects. Among these people, we can include medical students, healthcare professionals, university staff, transplanted patients, and their families. We believe that education and consciousness are central points in the donation and transplant process. Through this project, we could inform people about it, solving their doubts and myths and stimulating this kind of conversation among the family circle, making the moment when the family must make the decision much easier., Conclusions: Education and public awareness are essential for enhancing the number of organ donations. Therefore, events such as "Organ Donation Week" should be encouraged among medical schools., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The number of academic societies has been growing significantly in Brazilian universities, offering an extra opportunity for the development of educational activities and research. Because organ donation and transplantation is an area still insufficiently approached during the graduation of health professionals, we evaluated how academic societies might be a valuable tool., Methods: Participants of the course promoted by the Organ Transplantation Academic Society of the Hospital Dom Vicente Scherer were evaluated through the use of a questionnaire and cognitive tests with 16 multiple-choice questions about topics approached during the course, before and after the lectures. Topics approached consisted of a general introduction about transplantation in Brazil, brain death, organ allocation and removal, post-transplant follow-up, and clinical cases., Results: Of the 45 participants, 30 answered the tests at both times. The subjects were students of medicine, nursing, and phonoaudiology; 93.3% were organ donors, 84.6% said their families knew about this decision, and 65% had relatives who were organ donors. The mean score of correct answers was 7.63 of 16 before the activities and 12.54 after activities, demonstrating a 64.4% improvement., Conclusions: The improvement in performance suggests that academic societies are a useful resource for educational purposes and for students to get a deeper insight about organ donation and transplantation., (Copyright © 2016 Elsevier Inc. All rights reserved.)

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., (Copyright © 2013 John Wiley & Sons, Ltd.)

Aim: A low molecular weight chitosan (polyglucosamine, PG) was studied in overweight hyperlipemic patients under physical training. A double blind study was conducted in two groups of 30 patients (M/F; from 25 to 59 years)., Methods: Tablets containing PG (2 g/day) or placebo were given for a 4-month period during a physical training (+8 MET-hours/week). Anthropometric measures, caloric intake, blood pressure, LDL and HDL cholesterol, blood glucose and triacylglycerol were measured before and after the treatment. The groups were similar for the caloric intake and expenditure and ended up with positive results in most of the parameters examined., Results: In PG group compared to placebo a more significant (P<0.05, t test) reduction was found for body weight (respectively 6.9+/-1.87 vs 3.0+/-1.61 kg), waist circumference (7.3+/-2.49 vs 3.1+/-4.21 cm), LDL cholesterol (44+/-14.7 vs 12.5+/-12.6 mg/dL), triacylglycerol (52+/-29.3 vs 39+/-15.2 mg/dL); HDL increase was also higher (6+/-3.6 vs and 3+/-4.2 mg/dL). At baseline metabolic syndrome (MS) according to ATP III was present in 15 and 14 patients respectively in the group PG and placebo., Conclusions: Unexpectedly, at the end of the treatment MS was reduced in 12 cases of the PG group and in 3 cases only of the placebo group (P<0.05). Results indicate that PG may improve the effect of the physical training in moderately overweight patients with dyslipidemia and may be of some help in the treatment of MS.

Many effects believed to be because of angiotensin II (Ang II) are attributable to the action of endothelin (ET)-1, which is released/produced by Ang II. We investigated whether Ang II elicits its positive inotropic effect (PIE) by the action of endogenous ET-1, in addition to the role played by reactive oxygen species (ROS) in this mechanism. Cat cardiomyocytes were used for: (1) sarcomere shortening measurements; (2) ROS measurements by epifluorescence; (3) immunohistochemical staining for preproET-1, BigET-1, and ET-1; and (4) measurement of preproET-1 mRNA by RT-PCR. Cells were exposed to 1 nmol/L Ang II for 15 minutes. This low concentration of Ang II increases sarcomere shortening by 29.2+/-3.7% (P<0.05). This PIE was abrogated by Na+/H+ exchanger or Na+/Ca2+ exchanger reverse mode inhibition. The production of ROS increased in response to Ang II treatment (DeltaROS respect to control: 68+/-15 fluorescence units; P<0.05). The Ang II-induced PIE and ROS production were blocked by the Ang II type 1 receptor blocker losartan, the nonselective ET-1 receptor blocker TAK044, the selective ETA receptor blocker BQ-123, or the ROS scavenger N-(2-mercapto-propionyl)glycine. Exogenous ET-1 (0.4 nmol/L) induced a similar PIE and increase in ROS production to those caused by Ang II. Immunostaining for preproET-1, BigET-1, and ET-1 was positive in cardiomyocytes. The preproET-1 mRNA abundance increased from 100+/-4.6% in control to 241.9+/-39.9% in Ang II-treated cells (P<0.05). We conclude that the PIE after exposure to 1 nmol/L Ang II is due to endogenous ET-1 acting through the ETA receptor and triggering ROS production, Na+/H+ exchanger stimulation, and Na+/Ca2+ exchanger reverse mode activation.

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.