928 resultados para phosphite antioxidants


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Enteral nutrition is a technique that even though it was used in times immemorial, in the last 25 years has suffered a considerable development, from being considered a secondary therapeutic weapon destined only to feed the patient, to occupying an important status that goes beyond the single act of nourishing. The quantitative composition but overall the qualitative one, is object of an interesting argument in which a profile allowing the modulation of certain aspects of the organism response through the supplementation with different nutrients is searched. That includes from the keeping of the intestinal trophism and of the anti-bacteria intestinal barrier, so important to avoid the frightening multiple organ dysfunction, up to the lessening of the Systemic Response Inflammatory Syndrome (SRIS), going through the immuno-modulative feeding concepts, specific-feeding, pharmaco-nutrient or eco-nutrition. In this new dynamic not only certain nutrients such as glutamine, arginine, nucleotides, omega-3 fatty acids and many antioxidants have acquired importance, but also the manipulation of other molecules of a non- nutritional nature, such as hormones, cytokines and blockers. These aspects that imply passionate ways of investigation for the future are born from the better knowledge that is being acquired from such a severe pathophysiology processes such as sepsis and the organism response before fast and severe aggression; therefore, the modulation of that response through changes in the quantitative and qualitative formulas composition is being attempted.

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The aims of this study were to check whether different biomarkers of inflammatory, apoptotic, immunological or lipid pathways had altered their expression in the occluded popliteal artery (OPA) compared with the internal mammary artery (IMA) and femoral vein (FV) and to examine whether glycemic control influenced the expression of these genes. The study included 20 patients with advanced atherosclerosis and type 2 diabetes mellitus, 15 of whom had peripheral arterial occlusive disease (PAOD), from whom samples of OPA and FV were collected. PAOD patients were classified based on their HbA1c as well (HbA1c ≤ 6.5) or poorly (HbA1c > 6.5) controlled patients. Controls for arteries without atherosclerosis comprised 5 IMA from patients with ischemic cardiomyopathy (ICM). mRNA, protein expression and histological studies were analyzed in IMA, OPA and FV. After analyzing 46 genes, OPA showed higher expression levels than IMA or FV for genes involved in thrombosis (F3), apoptosis (MMP2, MMP9, TIMP1 and TIM3), lipid metabolism (LRP1 and NDUFA), immune response (TLR2) and monocytes adhesion (CD83). Remarkably, MMP-9 expression was lower in OPA from well-controlled patients. In FV from diabetic patients with HbA1c ≤6.5, gene expression levels of BCL2, CDKN1A, COX2, NDUFA and SREBP2 were higher than in FV from those with HbA1c >6.5. The atherosclerotic process in OPA from diabetic patients was associated with high expression levels of inflammatory, lipid metabolism and apoptotic biomarkers. The degree of glycemic control was associated with gene expression markers of apoptosis, lipid metabolism and antioxidants in FV. However, the effect of glycemic control on pro-atherosclerotic gene expression was very low in arteries with established atherosclerosis.

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Little information is available as to whether doses of iodide similar to those recommended in clinical practice for the prevention of iodine deficiency in pregnant women affect thyroid function. The aim of the present study was to analyse whether doses of iodide can affect thyroid function in adults, and evaluate its effect on plasma markers of oxidative stress, inflammation and acute-phase proteins. A total of thirty healthy volunteers (ten men and twenty women) with normal thyroid function were randomly assigned to three groups (n 10). Each group received a daily dose of 100, 200 or 300 μg of iodide in the form of KI for 6 months. Free tetraiodothyronine (FT4) levels at day 60 of the study were higher in the groups treated with 200 and 300 μg (P = 0·01), and correlated with the increase in urinary iodine (r 0·50, P = 0·007). This correlation lost its significance after adjustment for the baseline FT4. The baseline urinary iodine and FT4 correlated positively with the baseline glutathione peroxidase. On day 60, urinary iodine correlated with C-reactive protein (r 0·461, P = 0·018), and free triiodothyronine correlated with IL-6 (r - 0·429, P = 0·025). On day 60, the changes produced in urinary iodine correlated significantly with the changes produced in α1-antitrypsin (r 0·475, P = 0·014) and ceruloplasmin (r 0·599, P = 0·001). The changes in thyroid-stimulating hormone correlated significantly with the changes in α1-antitrypsin (r - 0·521, P = 0·005) and ceruloplasmin (r - 0·459, P = 0·016). In conclusion, the administration of an iodide supplement between 100 and 300 μg/d did not modify thyroid function in a population with adequate iodine intake. The results also showed a slight anti-inflammatory and antioxidative action of iodide.

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The aim of this study was to examine the responses of uric acid, antioxidant defences and pro-oxidant variables after a high-fat meal. Twenty-five healthy persons without criteria for the metabolic syndrome, underwent a high-fat meal with Supracal (60 g fat). Measurements were made at baseline and 3 h after the meal of TAG, uric acid, HDL-cholesterol, total proteins and oxidative stress. Following the high-fat meal, we detected a significant increase in pro-oxidative variables and a decrease in antioxidative variables. The uric acid concentrations were significantly lower after the high-fat meal and the reduction correlated significantly with the oxidative stress variables. The inverse relation between reduced uric acid and increased carbonylated proteins remained in multiple regression analysis. We conclude that uric acid is a powerful antioxidant and its reduction following a high-fat meal may be related with its acute antioxidative action.

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SUMMARY Pulmonary Pulmonary disease is the primary cause of morbidity and mortality in cystic fibrosis patients (CF). Airways of CF patients are early colonized by various bacteriae, and an intense inflammatory response participates to airways destruction. Accumulation of neutrophils releasing proteolytic enzymes and free radicals induce progressive lung tissue destruction in CF. Among several inflammatory mediators implicated in this process, chemotactic factors such as leukotriene B4 (LTB4), product of arachidonic omega-6 polyunsaturated fatty acid (PUFA), plays an important role. Many anti-inflammatory therapies including corticosteroids, ibuprofen, macrolides, antioxidants and antiproteinases have been proposed in CF over the last 20 years. In complement to these various approaches, dietary supplementation with polyunsaturated fatty acids (PUFA) omega-3, known to favor the synthesis of less inflammatory leukotriene B5 (LTB5), could also represent a potential. therapy. The objective of this thesis was to assess the impact of this nutritional approach on several CF neutrophil functions. In addition, we have also examined the influence of this approach on various clinical parameters, to assess the feasibility of future studies specifically oriented towards clinical effects. To that endeavour, a high performance liquid chromatography method has been developed and validated, allowing the simultaneous determination of LTB4 and LTB5 produced by stimulated human polymorphonuclear leukocytes. This method was applied for the analysis of samples collected from CF patients taking part to a double-blind, randomized, crossover placebo-controlled clinical trial aiming at evaluating in these patients the immunomodulatary effect of a liquid supplementation enriched in omega-3 PUFA in CF. This study has shown that omega-3 PUFA are incorporated in CF neutrophil membranes and results into a modulation of leucotrienes B production, as testified by a three fold decrease in LTB4/LTB5 ratio after omega-3 PUFA supplementation. However, no clinical improvement was observed upon omega-3 supplementation, very reproducible results observed allow to be optimistic for a future larger trial focused on clinical outcomes. In conclusion, even if the results show that omega-3 PUFA are absorbed by CF patients and that the subsequent decrease in LTB4/LTB5 ratio suggests that in such conditions, neutrophils may produce less pro-inflammatory mediators, the clinical relevance of those observations remains to be demonstrated. Future multicentric studies focusing on clinical endpoints are still warranted to determine the importance of omega-3 PUFA in CF therapeutics. RÉSUMÉ Les patients atteints de mucoviscidose (patients CF) souffrent d'infections pulmonaires récurrentes. Celles-ci provoquent un afflux permanent de neutrophiles dans le poumon, neutrophiles qui libèrent des enzymes protéolytiques et des radicaux libres responsables à long terme de la destruction du tissu pulmonaire et, finalement, de l'insuffisance respiratoire, première cause de morbidité et de mortalité chez ces patients. La réponse inflammatoire ainsi induite peut être réduite par divers traitements anti-inflammatoires, tels que corticoïdes, anti-inflammatoires non stéroïdiens ou azithromycine. L'apport oral en acides gras polyinsaturés (AGPI) oméga-3 pourrait être une autre approche thérapeutique intéressante. Ces nutriments sont décrits comme possédant des propriétés anti-inflammatoires notamment en favorisant la synthèse d'eicosanoïdes pourvus d'une activité inflammatoire moindre par rapport à ceux issus d'une autre famille d'AGPI, les oméga-6. Ce travail de thèse a pour objectif premier d'évaluer l'impact de cette approche nutritionnelle sur diverses fonctions du neutrophile chez des patients CF. Cependant un intérêt de nature prospective a également été porté à certains paramètres cliniques, afin d'évaluer la faisabilité d'une future étude axée sur des effets cliniques. Pour ce faire, une méthode de chromatographie liquide à haute performance couplée à un spectromètre de masse a été développée et validée. Cette analyse devait permettre le dosage simultané de deux eicosanoïdes, le leucotriène B4 (LTB4) issu des AGPI oméga-6 et le leucotriène B5 (LTB5) issu des AGPI oméga-3. Puis, une étude clinique, double aveugle, randomisée, croisée sans période de washout, mais contrôlée avec un placebo, a été mise au point pour évaluer l'effet immunomodulateur de ces AGPI oméga-3 donnés sous la forme d'un liquide nutritif chez des patients CF. Les résultats de cette étude ont permis de démontrer l'absorption intestinale des AGPI oméga-3 par les patients. De plus, leur administration a permis de modifier la production de teucotriène B. En effet, le ratio LTB4/LTB5 a été diminué de près de trois fois sous liquide nutritif enrichi en AGPI oméga-3. Enfin aucune différence n'a pu être notée pour les paramètres cliniques; toutefois les résultats reproductibles observés permettent d'envisager qu'une future étude multicentrique axée sur des effets cliniques est faisable. En conclusion, la modification de la composition en AGPI membranaires du neutrophile observée durant cette étude laisse penser que ces nutriments sont absorbés par les patients CF. La modulation de la production en LTBs qui en découle permet d'envisager un potentiel effet anti-inflammatoire. Toutefois, la relevance clinique de ces observations restent à être démontrée. A l'heure actuelle, une étude multicentrique, focalisée sur des paramètres cliniques, est nécessaire avant de pouvoir se prononcer sur l'utilisation des AGPI oméga-3 chez les patients CF.

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Plant-based whole foods provide thousands of bioactive metabolites to the human diet that reduce the risk of developing chronic diseases. β-Caryophyllene (CAR) is a common constituent of the essential oil of numerous plants, vegetables, fruits and medicinal herbs, and has been used as a flavouring agent since the 1930 s. Here, we report the antioxidant activity of CAR, its protective effect on liver fibrosis and its inhibitory capacity on hepatic stellate cell (HSC) activation. CAR was tested for the inhibition of lipid peroxidation and as a free radical scavenger. CAR had higher inhibitory capacity on lipid peroxidation than probucol, α-humulene and α-tocopherol. Also, CAR showed high scavenging activities against hydroxyl radical and superoxide anion. The activity of 5-lipoxygenase, an enzyme that actively participates in fibrogenesis, was significantly inhibited by CAR. Carbon tetrachloride-treated rats received CAR at 2, 20 and 200 mg/kg. CAR significantly improved liver structure, and reduced fibrosis and the expression of Col1a1, Tgfb1 and Timp1 genes. Oxidative stress was used to establish a model of HSC activation with overproduction of extracellular matrix proteins. CAR (1 and 10 μm) increased cell viability and significantly reduced the expression of fibrotic marker genes. CAR, a sesquiterpene present in numerous plants and foods, is as a natural antioxidant that reduces carbon tetrachloride-mediated liver fibrosis and inhibits hepatic cell activation.

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Alzheimer's disease is a frequent neurodegenerative disease, which affects more than one third of elderly persons over 80 years. No curative treatment is currently available for this disease, but symptomatic treatments have produced significant improvements in patients' condition. Cholinesterase inhibitors should be prescribed for early and moderate stages and memantine for more severe stages of the disease. These drugs have an impact on cognitive performances, may delay functional decline and improve behaviour disturbances. From a preventive perspective, evidence of benefit from early management of vascular risk factors is accumulating. In the near future, the improved comprehension of the underlying mechanisms of Alzheimer's disease will hopefully bring new treatments, thats will delay or modify its course.

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Abstract Genetic studies have shown an association between schizophrenia and a GAG trinucleotide repeat (TNR) polymorphism in the catalytic subunit (GCLC) of the glutamate cysteine ligase (GCL), the key enzyme for glutathione (GSH) synthesis. The present study was aimed at analyzing the influence of a GSH dysregulation of genetic origin on plasma thiols (total cysteine, homocysteine, and cysteine-glycine) and other free amino acid levels as well as fibroblast cultures GSH levels. Plasma thiols levels were also compared between patients and controls. As compared with patients with a low-risk GCLC GAG TNR genotype, patients with a high-risk genotype, having an impaired GSH synthesis, displayed a decrease of fibroblast GSH and plasma total cysteine levels, and an increase of the oxidized form of cysteine (cystine) content. Increased levels of plasma free serine, glutamine, citrulline, and arginine were also observed in the high-risk genotype. Taken together, the high-risk genotypes were associated with a subgroup of schizophrenia characterized by altered plasma thiols and free amino acid levels that reflect a dysregulation of redox control and an increased susceptibility to oxidative stress. This altered pattern potentially contributes to the development of a biomarker profile useful for early diagnosis and monitoring the effectiveness of novel drugs targeting redox dysregulation in schizophrenia. Antioxid. Redox Signal. 15, 2003-2010.

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Chagas disease, caused by Trypanosoma cruzi, represents an endemic among Latin America countries. The participation of free radicals, especially nitric oxide (NO), has been demonstrated in the pathophysiology of seropositive individuals with T. cruzi. In Chagas disease, increased NO contributes to the development of cardiomyopathy and megacolon. Metallothioneins (MTs) are efficient free radicals scavengers of NO in vitro and in vivo. Here, we developed a murine model of the chronic phase of Chagas disease using endemic T. cruzi RyCH1 in BALB/c mice, which were divided into four groups: infected non-treated (Inf), infected N-monomethyl-L-arginine treated (Inf L-NAME), non-infected L-NAME treated and non-infected vehicle-treated. We determined blood parasitaemia and NO levels, the extent of parasite nests in tissues and liver MT-I expression levels. It was observed that NO levels were increasing in Inf mice in a time-dependent manner. Inf L-NAME mice had fewer T. cruzi nests in cardiac and skeletal muscle with decreased blood NO levels at day 135 post infection. This affect was negatively correlated with an increase of MT-I expression (r = -0.8462, p < 0.0001). In conclusion, we determined that in Chagas disease, an unknown inhibitory mechanism reduces MT-I expression, allowing augmented NO levels.

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Les melanines són un grup heterogeni de polímers producte de reaccions enzimàtiques en els teixits vegetals que contenen compostos fenòlics o polifenòlics. Estudis recents han descobert algunes propietats benèfiques de les melanines sobre la salut, tals com antioxidants, antiinflamatòries, immunològiques i propietats anti-tumorals. Així, no només la seva eliminació ha de ser examinada, sinó que també podria considerar-se la seva addició a aliments funcionals de nova creació. D’aquesta manera, es requereix conèixer el mecanisme cinètic de la lanogènesi abans de la seva possible utilització industrial. S’ha desenvolupat un model cinètic per explicar la formació de melanina a partir de L-tirosina utilitzant polifenol oxidasa d’Agaricus bisporus i monitoritzant l'absorbància de la solució. Aquesta expressió permet descriure la formació de melanina en funció del temps de reacció i obtenir alguns paràmetres importants que defineixen el producte, com el coeficient d'extinció. L’absorbància comença a créixer després d'un període de latència en què es produeixen productes intermedis incolors. El coeficient d'extinció dels productes resultants no és un valor constant, perquè depèn de les condicions de cada experiment. La tirosinasa tingué un menor efecte catalitzador sobre la L-tirosina (primera reacció que catalitza), que sobre L-DOPA (segona reacció).

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The concept that optic nerve fiber loss might be reduced by neuroprotection arose in the mid 1990s. The subsequent research effort, focused mainly on rodent models, has not yet transformed into a successful clinical trial, but provides mechanistic understanding of retinal ganglion cell death and points to potential therapeutic strategies. This review highlights advances made over the last year. In excitotoxicity and axotomy models retinal ganglion cell death has been shown to result from a complex interaction between retinal neurons and Müller glia, which release toxic molecules including tumor necrosis factor alpha. This counteracts neuroprotection by neurotrophins such as nerve growth factor, which bind to p75NTR receptors on Müller glia stimulating the toxic release. Another negative effect against neurotrophin-mediated protection involves the action of LINGO-1 at trkB brain-derived neurotrophic factor (BDNF) receptors, and BDNF neuroprotection is enhanced by an antagonist to LINGO-1. As an alternative to pharmacotherapy, retinal defences can be stimulated by exposure to infrared radiation. The mechanisms involved in glaucoma and other optic nerve disorders are being clarified in rodent models, focusing on retrograde degeneration following axonal damage, excitotoxicity and inflammatory/autoimmune mechanisms. Neuroprotective strategies are being refined in the light of the mechanistic understanding.

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INTRODUCTION: Physical training programmes are based on provoking transitory states of fatigue in order to induce super compensation by the biological systems involved in the activity, in order to improve the athlete's medium-long term performance. The administration of nutritional supplements with antioxidant and immunomodulatory properties, such as Phlebodium decumanum and coenzyme Q10, can be a very advantageous means of achieving recovery from the inflammation and tissue damage caused by the stress of prolonged, intense exercise. METHODOLOGY: An experimental, longitudinal, double- blind experiment was conducted, with three randomised groups obtained from a sample of 30 male volleyball players (aged 22-32 years) at the University of Granada, with a high level of training (17 hours a week during the 6 months preceding the study). The effects were then evaluated of a month-long physical training programme, common to all the study groups, associated with the simultaneous administration of the following nutritional supplements: Phlebodium decumanum (4 capsules of 400 mg/capsule, daily), Experimental Group 1; Phlebodium decumanum (same dose andchedule as Group 1) plus coenzyme Q10 (4 capsules of 30 mg/ capsule, daily), Experimental Group 2; a placebo substance, Control Group. The following dependent blood variables were examined to assess the effects of the intervention on the basal immune and endocrine-metabolic profile: cortisol and interleukin-6, both related to the axis of exercise-induced stress; and lactic acid and ammonium, related essentially to the anaerobic metabolism of energy. RESULTS: All the study groups presented favourable adaptive changes with respect to the endocrine-metabolic and immune profile, as reflected by a significant decrease in the post-test concentrations of cortisol, interleukin 6, lactic acid and ammonium, compared to the values recorded before the physical activity with/without nutritional supplement, per protocol. The groups that achieved the most favourable profile were those which had received nutritional supplementation, rather than the placebo, and among the former, those which had received the double- strength supplement with Phlebodium decumanum plus coenzyme Q10. CONCLUSIONS: The intake of Phlebodium decumanum plus coenzyme Q10 for 4 weeks produced protective effects on the endocrine-metabolic and immune profile, which we attribute to the immunomodulatory and antioxidant properties of these substances, which are highly beneficial not only in terms of delaying fatigue and improving athletic performance, but also in reducing the risk of injuries associated with high intensity exercise.

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Malnutrition affects 40-50% of patients with ear, nose and throat (ENT) cancer. The aim of this study was to assess changes induced by a specific nutritional supplement enriched with n-3 polyunsaturated fatty acids, fiber and greater amounts of proteins and electrolytes, as compared with a standard nutritional supplement, on markers of inflammation, oxidative stress and metabolic status of ENT cancer patients undergoing radiotherapy (RT). Fourteen days after starting RT, 26 patients were randomly allocated to one of two groups, 13 supplemented with Prosure, an oncologic formula enriched with n-3 polyunsaturated fatty acids, fiber and greater amounts of proteins and electrolytes (specific supplement), and 13 supplemented with Standard-Isosource (standard supplement). Patients were evaluated before RT, and 14, 28 and 90 days after starting RT. The results showed that there were no significant differences between the groups, but greater changes were observed in the standard supplement group, such as a decline in body mass index (BMI), reductions in hematocrit, erythrocyte, eosinophil and albumin levels, and a rise in creatinine and urea levels. We concluded that metabolic, inflammatory and oxidative stress parameters were altered during RT, and began to normalize at the end of the study. Patients supplemented with Prosure showed an earlier normalization of these parameters, with more favorable changes in oxidative stress markers and a more balanced evolution, although the difference was not significant.

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Abstract A prospective 1-year follow-up study in ear, nose, and throat (ENT) cancer patients was carried out one year after radiotherapy to assess the effect of varying consumption of ω3 fatty acid according to whether they consumed more or less than the 50th percentile of ω3 fatty acids. Clinical, analytical, inflammatory (CRP and IL-6), and oxidative variables (TAC, GPx, GST, and SOD) were evaluated. The study comprised 31 patients (87.1% men), with a mean age of 61.3 ± 9.1 years. Hematological variables showed significant differences in the patients with a lower consumption of ω3 fatty acids. A lower mortality and longer survival were found in the group with ω3 fatty acid consumption ≥50th percentile but the differences were not significant. No significant difference was reached in toxicity, inflammation, and oxidative stress markers. The group with ω3 fatty acid consumption <50th percentile significantly experienced more hematological and immune changes.

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BACKGROUND Fragile X syndrome (FXS) is an inherited neurodevelopmental condition characterised by behavioural, learning disabilities, physical and neurological symptoms. In addition, an important degree of comorbidity with autism is also present. Considered a rare disorder affecting both genders, it first becomes apparent during childhood with displays of language delay and behavioural symptoms.Main aim: To show whether the combination of 10 mg/kg/day of ascorbic acid (vitamin C) and 10 mg/kg/day of α-tocopherol (vitamin E) reduces FXS symptoms among male patients ages 6 to 18 years compared to placebo treatment, as measured on the standardized rating scales at baseline, and after 12 and 24 weeks of treatment.Secondary aims: To assess the safety of the treatment. To describe behavioural and cognitive changes revealed by the Developmental Behaviour Checklist Short Form (DBC-P24) and the Wechsler Intelligence Scale for Children-Revised. To describe metabolic changes revealed by blood analysis. To measure treatment impact at home and in an academic environment. METHODS/DESIGN A phase II randomized, double-blind pilot clinical trial. SCOPE male children and adolescents diagnosed with FXS, in accordance with a standardized molecular biology test, who met all the inclusion criteria and none of the exclusion criteria. INSTRUMENTATION clinical data, blood analysis, Wechsler Intelligence Scale for Children-Revised, Conners parent and teacher rating scale scores and the DBC-P24 results will be obtained at the baseline (t0). Follow up examinations will take place at 12 weeks (t1) and 24 weeks (t2) of treatment. DISCUSSION A limited number of clinical trials have been carried out on children with FXS, but more are necessary as current treatment possibilities are insufficient and often provoke side effects. In the present study, we sought to overcome possible methodological problems by conducting a phase II pilot study in order to calculate the relevant statistical parameters and determine the safety of the proposed treatment. The results will provide evidence to improve hyperactivity control and reduce behavioural and learning problems using ascorbic acid (vitamin C) and α-tocopherol (vitamin E). The study protocol was approved by the Regional Government Committee for Clinical Trials in Andalusia and the Spanish agency for drugs and health products. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT01329770 (29 March 2011).