982 resultados para setup crossover
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For the general practitioner to be able to prescribe optimal therapy to his individual hypertensive patients, he needs accurate information on the therapeutic agents he is going to administer and practical treatment strategies. The information on drugs and drug combinations has to be applicable to the treatment of individual patients and not just patient study groups. A basic requirement is knowledge of the dose-response relationship for each compound in order to choose the optimal therapeutic dose. Contrary to general assumption, this key information is difficult to obtain and often not available to the physician for many years after marketing of a drug. As a consequence, excessive doses are often used. Furthermore, the physician needs comparative data on the various antihypertensive drugs that are applicable to the treatment of individual patients. In order to minimize potential side effects due to unnecessary combinations of compounds, the strategy of sequential monotherapy is proposed, with the goal of treating as many patients as possible with monotherapy at optimal doses. More drug trials of a crossover design and more individualized analyses of the results are badly needed to provide the physician with information that he can use in his daily practice. In this time of continuous intensive development of new antihypertensive agents, much could be gained in enhanced efficacy and reduced incidence of side effects by taking a closer look at the drugs already available and using them more appropriately in individual patients.
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Objective: Integration of the radiotherapy technologist "know-how" in the Gamma Knife treatment processMaterials and Methods: Gamma Knife (GK) treatments started in July 2010 at the GK Center in C.H.U.V. with the Leksell Gamma KnifeR Perfexion?(Elekta AB, Sweden). The multidisciplinary GK team involves neurosurgeons, radio-oncologists, physicists, neuroradiologists, nurses and technologists, aiming at a full integration for optimal patient management.Results: Between July and December 2010, 60 patients have been treated. Required stereotactic imaging involves IRM, CT scan (and angiography for AVM). All the steps in the treatment process (Leksell coordinate frame fixation, imaging, planning, treatment) are supervised by the members of the multidisciplinary team. In our experience, radiotherapy technologist (RTT) have acquired an important role in the multidisciplinary team communication and integration. Specifically, the RTT are responsible of: supervision of the image acquisition, performing the Gamma Knife unit control tests, patient setup, and patient surveillance during treatment.Conclusion: RTT have a fundamental role in the communication within the team, between the team and the patient and also to assure the patient security. Our experience shows that it is possible and required to involve RTT in all steps of the GK treatment process, to guarantee the best GK treatment possible.
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In response to the mandate on Load and Resistance Factor Design (LRFD) implementations by the Federal Highway Administration (FHWA) on all new bridge projects initiated after October 1, 2007, the Iowa Highway Research Board (IHRB) sponsored these research projects to develop regional LRFD recommendations. The LRFD development was performed using the Iowa Department of Transportation (DOT) Pile Load Test database (PILOT). To increase the data points for LRFD development, develop LRFD recommendations for dynamic methods, and validate the results ofLRFD calibration, 10 full-scale field tests on the most commonly used steel H-piles (e.g., HP 10 x 42) were conducted throughout Iowa. Detailed in situ soil investigations were carried out, push-in pressure cells were installed, and laboratory soil tests were performed. Pile responses during driving, at the end of driving (EOD), and at re-strikes were monitored using the Pile Driving Analyzer (PDA), following with the CAse Pile Wave Analysis Program (CAPWAP) analysis. The hammer blow counts were recorded for Wave Equation Analysis Program (WEAP) and dynamic formulas. Static load tests (SLTs) were performed and the pile capacities were determined based on the Davisson’s criteria. The extensive experimental research studies generated important data for analytical and computational investigations. The SLT measured loaddisplacements were compared with the simulated results obtained using a model of the TZPILE program and using the modified borehole shear test method. Two analytical pile setup quantification methods, in terms of soil properties, were developed and validated. A new calibration procedure was developed to incorporate pile setup into LRFD.
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Preclinical studies implicate a role for α₁-noradrenergic receptors in the effects of psychostimulants, including 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"). The present study evaluated the effects of the α₁-noradrenergic receptor antagonist doxazosin on the acute pharmacodynamic and pharmacokinetic response to MDMA in 16 healthy subjects. Doxazosin (8 mg/d) or placebo was administered for 3 days before MDMA (125 mg) or placebo using a randomized, double-blind, placebo-controlled, 4-session, crossover design. Doxazosin reduced MDMA-induced elevations in blood pressure, body temperature, and moderately attenuated positive mood but enhanced tachycardia associated with MDMA. The results indicate that α₁-adrenergic receptors contribute to the acute cardiostimulant and to a minor extent possibly also to the thermogenic and euphoric effects of MDMA in humans.
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This study was designed to evaluate in healthy volunteers the renal hemodynamic and tubular effects of the orally active angiotensin II receptor antagonist losartan (DuP 753 or MK 954). Losartan or a placebo was administered to 23 subjects maintained on a high-sodium (200 mmol/d) or a low-sodium (50 mmol/d) diet in a randomized, double-blind, crossover study. The two 6-day diet periods were separated by a 5-day washout period. On day 6, the subjects were water loaded, and blood pressure, renal hemodynamics, and urinary electrolyte excretion were measured for 6 hours after a single 100-mg oral dose of losartan (n = 16) or placebo (n = 7). Losartan induced no significant changes in blood pressure, glomerular filtration rate, or renal blood flow in these water-loaded subjects, whatever the sodium diet. In subjects on a low-salt diet, losartan markedly increased urinary sodium excretion from 115 +/- 9 to 207 +/- 21 mumol/min (P < .05). The fractional excretion of endogenous lithium was unchanged, suggesting no effect of losartan on the early proximal tubule in our experimental conditions. Losartan also increased urine flow rate (from 10.5 +/- 0.4 to 13.1 +/- 0.6 mL/min, P < .05); urinary potassium excretion (from 117 +/- 6.9 to 155 +/- 11 mumol/min); and the excretion of chloride, magnesium, calcium, and phosphate. In subjects on a high-salt diet, similar effects of losartan were observed, but the changes induced by the angiotensin II antagonist did not reach statistical significance. In addition, losartan demonstrated significant uricosuric properties with both sodium diets.(ABSTRACT TRUNCATED AT 250 WORDS)
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BACKGROUND: Controlled transcranial stimulation of the brain is part of clinical treatment strategies in neuropsychiatric diseases such as depression, stroke, or Parkinson's disease. Manipulating brain activity by transcranial stimulation, however, inevitably influences other control centers of various neuronal and neurohormonal feedback loops and therefore may concomitantly affect systemic metabolic regulation. Because hypothalamic adenosine triphosphate-sensitive potassium channels, which function as local energy sensors, are centrally involved in the regulation of glucose homeostasis, we tested whether transcranial direct current stimulation (tDCS) causes an excitation-induced transient neuronal energy depletion and thus influences systemic glucose homeostasis and related neuroendocrine mediators.METHODS: In a crossover design testing 15 healthy male volunteers, we increased neuronal excitation by anodal tDCS versus sham and examined cerebral energy consumption with (31)phosphorus magnetic resonance spectroscopy. Systemic glucose uptake was determined by euglycemic-hyperinsulinemic glucose clamp, and neurohormonal measurements comprised the parameters of the stress systems.RESULTS: We found that anodic tDCS-induced neuronal excitation causes an energetic depletion, as quantified by (31)phosphorus magnetic resonance spectroscopy. Moreover, tDCS-induced cerebral energy consumption promotes systemic glucose tolerance in a standardized euglycemic-hyperinsulinemic glucose clamp procedure and reduces neurohormonal stress axes activity.CONCLUSIONS: Our data demonstrate that transcranial brain stimulation not only evokes alterations in local neuronal processes but also clearly influences downstream metabolic systems regulated by the brain. The beneficial effects of tDCS on metabolic features may thus qualify brain stimulation as a promising nonpharmacologic therapy option for drug-induced or comorbid metabolic disturbances in various neuropsychiatric diseases.
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Abstract - Cannabis: what are the risks ? Cannabinoids from cannabis have a dual use and display often opposite pharmacological properties depending on the circumstances of use and the administered dose. Cannabinoids constitute mainly a recreative or addictive substance, but also a therapeutic drug. They can be either neurotoxic or neuroprotector, carcinogenic or an anti-cancer drug, hyperemetic or antiemetic, pro-inflammatory or anti-inflammatory... Improvement in in-door cultivation techniques and selection of high yield strains have resulted in a steadily increase of THC content. Cannabis is the most frequently prohibited drug used in Switzerland and Western countries. About half of teenagers have already experimented cannabis consumption. About 10% of cannabis users smoke it daily and can be considered as cannabis-dependant. About one third of these cannabis smokers are chronically intoxicated. THC, the main psychoactive drug interacts with the endocannnabinoid system which is made of cellular receptors, endogenous ligands and a complex intra-cellular biosynthetic, degradation and intra-cellular messengers machinery. The endocannabinoid system plays a major role in the fine tuning of the nervous system. It is thought to be important in memory, motor learning, and synaptic plasticity. At psychoactive dose, THC impairs psychomotor and neurocognitive performances. Learning and memory abilities are diminished. The risk to be responsible of a traffic car accident is slightly increased after administration of cannabis alone and strongly increased after combined use of alcohol and cannabis. With the exception of young children, cannabis intake does not lead to potentially fatal intoxication. However, cannabis exposure can act as trigger for cardiovascular accidents in rare vulnerable people. Young or vulnerable people are more at risk to develop a psychosis at adulthood and/or to become cannabis-dependant. Epidemiological studies have shown that the risk to develop a schizophrenia at adulthood is increased for cannabis smokers, especially for those who are early consumers. Likewise for the risk of depression and suicide attempt. Respiratory disease can be worsen after cannabis smoking. Pregnant and breast-feeding mothers should not take cannabis because THC gets into placenta and concentrates in breast milk. The most sensitive time-period to adverse side-effects of cannabis starts from foetus and extends to adolescence. The reason could be that the endocannabinoid system, the main target of THC, plays a major role in the setup of neuronal networks in the immature brain. The concomitant use of other psychoactive drugs such as alcohol, benzodiazepines or cocaine should be avoided because of possible mutual interactions. Furthermore, it has been demonstrated that a cross-sensitisation exists between most addictive drugs at the level of the brain reward system. Chronic use of cannabis leads to tolerance and withdrawals symptoms in case of cannabis intake interruption. Apart from the aforementioned unwanted side effects, cannabis displays useful and original medicinal properties which are currently under scientific evaluation. At the moment the benefit/risk ratio is not yet well assessed. Several minor phytocannabinoids or synthetic cannabinoids devoid of psychoactive properties could find their way in the modern pharmacopoeia (e.g. ajulemic acid). For therapeutic purposes, special cannabis varieties with unique cannabinoids composition (e.g. a high cannabidiol content) are preferred over those which are currently used for recreative smoking. The administration mode also differs in such a way that inhalation of carcinogenic pyrolytic compounds resulting from cannabis smoking is avoided. This can be achieved by inhaling cannabis vapors at low temperature with a vaporizer device. Résumé Les cannabinoïdes contenus dans la plante de cannabis ont un double usage et possèdent des propriétés opposées suivant les circonstances et les doses employées. Les cannabinoïdes, essentiellement drogue récréative ou d'abus pourraient, pour certains d'entre eux, devenir des médicaments. Selon les conditions d'utilisation, ils peuvent être neurotoxiques ou neuroprotecteurs, carcinogènes ou anticancéreux, hyper-émétiques ou antiémétiques, pro-inflammatoires ou anti-inflammatoires... Les techniques de culture sous serre indoor ainsi que la sélection de variétés de cannabis à fort potentiel de production ont conduit à un accroissement notable des taux de THC. Le cannabis est la drogue illégale la plus fréquemment consommée en Suisse et ailleurs dans le monde occidental. Environ la moitié des jeunes ont déjà expérimenté le cannabis. Environ 10 % des consommateurs le fument quotidiennement et en sont devenus dépendants. Un tiers de ces usagers peut être considéré comme chroniquement intoxiqué. Le THC, la principale substance psychoactive du cannabis, interagit avec le "système endocannabinoïde". Ce système est composé de récepteurs cellulaires, de ligands endogènes et d'un dispositif complexe de synthèse, de dégradation, de régulation et de messagers intra-cellulaires. Le système endocannabinoïde joue un rôle clé dans le réglage fin du système nerveux. Les endocannabinoïdes régulent la mémorisation, l'apprentissage moteur et la plasticité des liaisons nerveuses. À dose psychoactive, le THC réduit les performances psychomotrices et neurocognitives. Les facultés d'apprentissage et de mémorisation sont diminuées. Le risque d'être responsable d'un accident de circulation est augmenté après prise de cannabis, et ceci d'autant plus que de l'alcool aura été consommé parallèlement. À l'exception des jeunes enfants, la consommation de cannabis n'entraîne pas de risque potentiel d'intoxication mortelle. Toutefois, le cannabis pourrait agir comme facteur déclenchant d'accident cardiovasculaire chez de rares individus prédisposés. Les individus jeunes, et/ou vulnérables ont un risque significativement plus élevé de développer une psychose à l'âge adulte ou de devenir dépendant au cannabis. Des études épidémiologiques ont montré que le risque de développer une schizophrénie à l'âge adulte était augmenté pour les consommateurs de cannabis et ceci d'autant plus que l'âge de début de consommation était précoce. Il en va de même pour le risque de dépression. Les troubles respiratoires pourraient être exacerbés par la prise de cannabis. Les femmes enceintes et celles qui allaitent ne devraient pas consommer de cannabis car le THC traverse la barrière hémato-placentaire, en outre, il se concentre dans le lait maternel. La période de la vie la plus sensible aux effets néfastes du cannabis correspond à celle allant du foetus à l'adolescent. Le système endocannabinoïde sur lequel agit le THC serait en effet un acteur majeur orchestrant le développement des réseaux neuronaux dans le cerveau immature. La prise concomitante d'autres psychotropes comme l'alcool, les benzodiazépines ou la cocaïne conduit à des renforcements mutuels de leurs effets délétères. De plus, il a été montré l'existence d'une sensibilité croisée pour la majorité des psychotropes qui agissent sur le système de la récompense, le cannabis y compris, ce qui augmente ainsi le risque de pharmacodépendance. La prise régulière de doses élevées de cannabis entraîne l'apparition d'une tolérance et de symptômes de sevrage discrets à l'arrêt de la consommation. À part les effets négatifs mentionnés auparavant, le cannabis possède des propriétés médicales originales qui sont l'objet d'études attentives. Plusieurs cannabinoïdes mineurs naturels ou synthétiques, comme l'acide ajulémique, pourraient trouver un jour une place dans la pharmacopée. En usage thérapeutique, des variétés particulières de cannabis sont préférées, par exemple celles riches en cannabidiol non psychoactif. Le mode d'administration diffère de celui utilisé en mode récréatif. Par exemple, la vaporisation des cannabinoïdes à basse température est préférée à l'inhalation du "joint".
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BACKGROUND AND PURPOSE: The major drug-metabolizing enzymes for the oxidation of oxycodone are CYP2D6 and CYP3A. A high interindividual variability in the activity of these enzymes because of genetic polymorphisms and/or drug-drug interactions is well established. The possible role of an active metabolite in the pharmacodynamics of oxycodone has been questioned and the importance of CYP3A-mediated effects on the pharmacokinetics and pharmacodynamics of oxycodone has been poorly explored. EXPERIMENTAL APPROACH: We conducted a randomized crossover (five arms) double-blind placebo-controlled study in 10 healthy volunteers genotyped for CYP2D6. Oral oxycodone (0.2 mg x kg(-1)) was given alone or after inhibition of CYP2D6 (with quinidine) and/or of CYP3A (with ketoconazole). Experimental pain (cold pressor test, electrical stimulation, thermode), pupil size, psychomotor effects and toxicity were assessed. KEY RESULTS: CYP2D6 activity was correlated with oxycodone experimental pain assessment. CYP2D6 ultra-rapid metabolizers experienced increased pharmacodynamic effects, whereas cold pressor test and pupil size were unchanged in CYP2D6 poor metabolizers, relative to extensive metabolizers. CYP2D6 blockade reduced subjective pain threshold (SPT) for oxycodone by 30% and the response was similar to placebo. CYP3A4 blockade had a major effect on all pharmacodynamic assessments and SPT increased by 15%. Oxymorphone C(max) was correlated with SPT assessment (rho(S)= 0.7) and the only independent positive predictor of SPT. Side-effects were observed after CYP3A4 blockade and/or in CYP2D6 ultra-rapid metabolizers. CONCLUSIONS AND IMPLICATIONS: The modulation of CYP2D6 and CYP3A activities had clear effects on oxycodone pharmacodynamics and these effects were dependent on CYP2D6 genetic polymorphism.
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The renal site of the natriuretic effect of human, atrial natriuretic peptide (hANP) was studied using clearance techniques in eight salt-loaded normal volunteers undergoing maximal water diuresis. Lithium was used as a marker of proximal sodium reabsorption. According to a two-way, single blind, crossover design, hANP (Met12-(3-28)-eicosahexapeptide, (2 micrograms/min) or its vehicle (Ve) were infused for two hours, followed by a two-hour recovery period. Blood pressure, heart rate and insulin clearance remained unchanged. During hANP infusion, the filtration fraction increased slightly from 19.6 to 24.3% (P less than 0.001), fractional water excretion rose transiently at the beginning of the infusion. Fractional excretion of sodium increased markedly from 2.2% to 7.4% (P less than 0.001) but remained unchanged with Ve. ANP increased fractional excretion of lithium slightly from 46 to 58% (P less than 0.01), while it remained stable at 47% during Ve. The distal tubular rejection fraction of sodium calculated from sodium and lithium clearances rose markedly from 4.7 to 13% (P less than 0.001) and returned to 6.2% at the end of the recovery period. Thus, under salt loading and water diuresis conditions, hANP infusion did not alter GFR, but reduced proximal reabsorption of sodium, and markedly enhanced the fraction of sodium escaping distal tubular reabsorption, suggesting that hANP-induced natriuresis is due, for an important part, to inhibition of sodium reabsorption in the distal nephron.
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Humans experience the self as localized within their body. This aspect of bodily self-consciousness can be experimentally manipulated by exposing individuals to conflicting multisensory input, or can be abnormal following focal brain injury. Recent technological developments helped to unravel some of the mechanisms underlying multisensory integration and self-location, but the neural underpinnings are still under investigation, and the manual application of stimuli resulted in large variability difficult to control. This paper presents the development and evaluation of an MR-compatible stroking device capable of presenting moving tactile stimuli to both legs and the back of participants lying on a scanner bed while acquiring functional neuroimaging data. The platform consists of four independent stroking devices with a travel of 16-20 cm and a maximum stroking velocity of 15 cm/s, actuated over non-magnetic ultrasonic motors. Complemented with virtual reality, this setup provides a unique research platform allowing to investigate multisensory integration and its effects on self-location under well-controlled experimental conditions. The MR-compatibility of the system was evaluated in both a 3 and a 7 Tesla scanner and showed negligible interference with brain imaging. In a preliminary study using a prototype device with only one tactile stimulator, fMRI data acquired on 12 healthy participants showed visuo-tactile synchrony-related and body-specific modulations of the brain activity in bilateral temporoparietal cortex.
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OBJECTIVES: We investigated the influence of angiotensin receptor blockade and angiotensin-converting enzyme inhibition on stress-induced platelet activation in hypertensive patients. Secondary aims were effects on inflammation, coagulation, and endothelial function. METHODS: Following a 4-week placebo period, 25 hypertensive patients entered a double-blind, crossover study comparing enalapril (20 mg once daily) and losartan (100 mg once daily) treatment (each for 8 weeks). Patients were studied at rest and after a standardized exercise test. RESULTS: Mean arterial pressure was reduced from 119 ± 2 to 104 ± 2 (enalapril) and 106 ± 2 (losartan) mmHg (both P <0.001). Plasma angiotensin II decreased from 2.4 ± 0.4 to 0.5 ± 0.1 pmol/l with enalapril, and increased to 7.2 ± 1.3 pmol/l with losartan (both P <0.001). Exercise-evoked platelet activation, as evidenced by increased numbers of P-selectin-positive platelets (P <0.01), elevated circulating platelet-platelet aggregates (P <0.01) and soluble P-selectin levels (P <0.001), and increased platelet responsiveness to adenosine diphosphate and thrombin (both P <0.05). Neither drug influenced these markers of platelet activation at rest or following exercise. Markers of inflammation (high-sensitivity C reactive protein, interleukin-6, tissue necrosis factor-α), coagulation (tissue plasminogen activator antigen, prothrombin fragment F1+2), and endothelial function (von Willebrand factor, soluble vascular cellular adhesion molecule-1, and intercellular adhesion molecule-1) were also uninfluenced by treatment. CONCLUSION: Enalapril and losartan failed to reduce platelet activity both at rest and during exercise in hypertensive patients. Markers of inflammation, coagulation, and endothelial function were similarly unaffected. Inhibition of the renin-angiotensin system promotes its beneficial effects in hypertension through mechanisms other than platelet inhibition.
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BACKGROUND: Aromatase inhibitors provide superior disease control when compared with tamoxifen as adjuvant therapy for postmenopausal women with endocrine-responsive early breast cancer. PURPOSE: To present the design, history, and analytic challenges of the Breast International Group (BIG) 1-98 trial: an international, multicenter, randomized, double-blind, phase-III study comparing the aromatase inhibitor letrozole with tamoxifen in this clinical setting. METHODS: From 1998-2003, BIG 1-98 enrolled 8028 women to receive monotherapy with either tamoxifen or letrozole for 5 years, or sequential therapy of 2 years of one agent followed by 3 years of the other. Randomization to one of four treatment groups permitted two complementary analyses to be conducted several years apart. The first, reported in 2005, provided a head-to-head comparison of letrozole versus tamoxifen. Statistical power was increased by an enriched design, which included patients who were assigned sequential treatments until the time of the treatment switch. The second, reported in late 2008, used a conditional landmark approach to test the hypothesis that switching endocrine agents at approximately 2 years from randomization for patients who are disease-free is superior to continuing with the original agent. RESULTS: The 2005 analysis showed the superiority of letrozole compared with tamoxifen. The patients who were assigned tamoxifen alone were unblinded and offered the opportunity to switch to letrozole. Results from other trials increased the clinical relevance about whether or not to start treatment with letrozole or tamoxifen, and analysis plans were expanded to evaluate sequential versus single-agent strategies from randomization. LIMITATIONS: Due to the unblinding of patients assigned tamoxifen alone, analysis of updated data will require ascertainment of the influence of selective crossover from tamoxifen to letrozole. CONCLUSIONS: BIG 1-98 is an example of an enriched design, involving complementary analyses addressing different questions several years apart, and subject to evolving analytic plans influenced by new data that emerge over time.
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BACKGROUND: Epidemiologic and experimental data have suggested that chlorogenic acid, which is a polyphenol contained in green coffee beans, prevents diet-induced hepatic steatosis and insulin resistance. OBJECTIVE: We assessed whether the consumption of chlorogenic acid-rich coffee attenuates the effects of short-term fructose overfeeding, dietary conditions known to increase intrahepatocellular lipids (IHCLs), and blood triglyceride concentrations and to decrease hepatic insulin sensitivity in healthy humans. DESIGN: Effects of 3 different coffees were assessed in 10 healthy volunteers in a randomized, controlled, crossover trial. IHCLs, hepatic glucose production (HGP) (by 6,6-d2 glucose dilution), and fasting lipid oxidation were measured after 14 d of consumption of caffeinated coffee high in chlorogenic acid (C-HCA), decaffeinated coffee high in chlorogenic acid, or decaffeinated coffee with regular amounts of chlorogenic acid (D-RCA); during the last 6 d of the study, the weight-maintenance diet of subjects was supplemented with 4 g fructose · kg(-1) · d(-1) (total energy intake ± SD: 143 ± 1% of weight-maintenance requirements). All participants were also studied without coffee supplementation, either with 4 g fructose · kg(-1) · d(-1) (high fructose only) or without high fructose (control). RESULTS: Compared with the control diet, the high-fructose diet significantly increased IHCLs by 102 ± 36% and HGP by 16 ± 3% and decreased fasting lipid oxidation by 100 ± 29% (all P < 0.05). All 3 coffees significantly decreased HGP. Fasting lipid oxidation increased with C-HCA and D-RCA (P < 0.05). None of the 3 coffees significantly altered IHCLs. CONCLUSIONS: Coffee consumption attenuates hepatic insulin resistance but not the increase of IHCLs induced by fructose overfeeding. This effect does not appear to be mediated by differences in the caffeine or chlorogenic acid content. This trial was registered at clinicaltrials.gov as NCT00827450.
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CONTEXT: The Fracture Reduction Evaluation of Denosumab in Osteoporosis Every 6 Months (FREEDOM) extension is evaluating the long-term efficacy and safety of denosumab for up to 10 years. OBJECTIVE: The objective of the study was to report results from the first 3 years of the extension, representing up to 6 years of denosumab exposure. DESIGN, SETTING, AND PARTICIPANTS: This was a multicenter, international, open-label study of 4550 women. INTERVENTION: Women from the FREEDOM denosumab group received 3 more years of denosumab for a total of 6 years (long-term) and women from the FREEDOM placebo group received 3 years of denosumab (crossover). MAIN OUTCOME MEASURES: Bone turnover markers (BTMs), bone mineral density (BMD), fracture, and safety data are reported. RESULTS: Reductions in BTMs were maintained (long-term) or achieved rapidly (crossover) after denosumab administration. In the long-term group, BMD further increased for cumulative 6-year gains of 15.2% (lumbar spine) and 7.5% (total hip). During the first 3 years of denosumab treatment, the crossover group had significant gains in lumbar spine (9.4%) and total hip (4.8%) BMD, similar to the long-term group during the 3-year FREEDOM trial. In the long-term group, fracture incidences remained low and below the rates projected for a virtual placebo cohort. In the crossover group, 3-year incidences of new vertebral and nonvertebral fractures were similar to those of the FREEDOM denosumab group. Incidence rates of adverse events did not increase over time. Six participants had events of osteonecrosis of the jaw confirmed by adjudication. One participant had a fracture adjudicated as consistent with atypical femoral fracture. CONCLUSION: Denosumab treatment for 6 years remained well tolerated, maintained reduced bone turnover, and continued to increase BMD. Fracture incidence remained low.
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Background: Glutathione (GSH) dysregulation at the gene, protein and functional levels observed in schizophrenia patients, and schizophrenia-like anomalies in GSH deficit experimental models, suggest that genetic glutathione synthesis impairments represent one major risk factor for the disease (Do et al., 2009). In a randomized, double blind, placebo controlled, add-on clinical trial of 140 patients, the GSH precursor N-Acetyl-Cysteine (NAC, 2 g/day, 6 months) significantly improved the negative symptoms and reduced side-effects due to antipsychotics (Berk et al., 2008). In a subset of patients (n=7), NAC (2 g/day, 2 months, cross-over design) also improved auditory evoked potentials, the NMDAdependent mismatch negativity (Lavoie et al, 2008). Methods: To determine whether increased GSH levels would modulate the topography of functional brain connectivity, we applied a multivariate phase synchronization (MPS) estimator (Knyazeva et al, 2008) to dense-array EEGs recorded during rest with eyes closed at the protocol onset, the point of crossover, and at its end. Phase synchronization phenomena are appealing because they can be associated to synchronized phases while the amplitudes stay uncorrelated. MPS measures the degree of interactions among the recorded neuronal oscillators by quantifiying to what extent they behave like a macro-oscillator (i.e. the oscillators are phase synchronous). To assess the whole-head synchronization topography, we computed the MPS sensor-wise over the cluster of locations defined by the sensor itself and he surrounding ones belonging to its second-order neighborhood (Carmeli et al, 2005). Such a cluster spans about 12 cm on average. Abstracts 245 Results: The whole-head imaging revealed a specific synchronization landscape in NAC compared to placebo condition. In particular, NAC increased MPS over frontal and left temporal regions in a frequency-specific manner. Importantly, the topography and direction of MPS changes were similar and robust in all 7 patients. Moreover, these changes correlated with the changes in the Liddle's score of disorganization (Liddle, 1987) thus linking EEG synchronization to the improvement of clinical picture. Discussion: The data suggest an important pathway towards new therapeutic strategies that target GSH dysregulation in schizophrenia. They also show the utility of MPS mapping as a marker of treatment efficacy.