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Effects of Oral Lycopene Supplementation on Vascular Function in Patients with Cardiovascular Disease and Healthy Volunteers: A Randomised Controlled Trial  [PDF]
Parag R. Gajendragadkar, Annette Hubsch, Kaisa M. M?ki-Pet?j?, Martin Serg, Ian B. Wilkinson, Joseph Cheriyan
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0099070
Abstract: Aims The mechanisms by which a ‘Mediterranean diet’ reduces cardiovascular disease (CVD) burden remain poorly understood. Lycopene is a potent antioxidant found in such diets with evidence suggesting beneficial effects. We wished to investigate the effects of lycopene on the vasculature in CVD patients and separately, in healthy volunteers (HV). Methods and Results We randomised 36 statin treated CVD patients and 36 healthy volunteers in a 2:1 treatment allocation ratio to either 7 mg lycopene or placebo daily for 2 months in a double-blind trial. Forearm responses to intra-arterial infusions of acetylcholine (endothelium-dependent vasodilatation; EDV), sodium nitroprusside (endothelium-independent vasodilatation; EIDV), and NG-monomethyl-L-arginine (basal nitric oxide (NO) synthase activity) were measured using venous plethysmography. A range of vascular and biochemical secondary endpoints were also explored. EDV in CVD patients post-lycopene improved by 53% (95% CI: +9% to +93%, P = 0.03 vs. placebo) without changes to EIDV, or basal NO responses. HVs did not show changes in EDV after lycopene treatment. Blood pressure, arterial stiffness, lipids and hsCRP levels were unchanged for lycopene vs. placebo treatment groups in the CVD arm as well as the HV arm. At baseline, CVD patients had impaired EDV compared with HV (30% lower; 95% CI: ?45% to ?10%, P = 0.008), despite lower LDL cholesterol (1.2 mmol/L lower, 95% CI: ?1.6 to ?0.9 mmol/L, P<0.001). Post-therapy EDV responses for lycopene-treated CVD patients were similar to HVs at baseline (2% lower, 95% CI: ?30% to +30%, P = 0.85), also suggesting lycopene improved endothelial function. Conclusions Lycopene supplementation improves endothelial function in CVD patients on optimal secondary prevention, but not in HVs. Trial Registration ClinicalTrials.gov NCT01100385
Exposure to ambient concentrations of particulate air pollution does not influence vascular function or inflammatory pathways in young healthy individuals
Elvira V Br?uner, Peter M?ller, Lars Barregard, Lars O Dragsted, Marianne Glasius, Peter W?hlin, Peter Vinzents, Ole Raaschou-Nielsen, Steffen Loft
Particle and Fibre Toxicology , 2008, DOI: 10.1186/1743-8977-5-13
Abstract: Twenty-nine subjects participated in a randomized, two-factor crossover study with or without biking exercise for 180 minutes and with 24 hour exposure to particle rich (number concentrations, NC: 11600 ± 5600 per cm3, mass concentrations: 13.8 ± 7.4 μg/m3 and 10.5 ± 4.8 μg/m3 for PM10-2.5 and PM2.5, respectively) or particle filtered (NC: 555 ± 1053 per cm3) air collected above a busy street. Microvascular function was assessed non-invasively by measuring digital peripheral artery tone following arm ischemia. Biomarkers included haemoglobin, red blood cells, platelet count, coagulation factors, C-reactive protein, fibrinogen, interleukin-6, tumour necrosis factor α, lag time to copper-induced oxidation of plasma lipids and protein oxidation measured as 2-aminoadipic semialdehyde in plasma.No statistically significant differences were observed on microvascular function or the biomarkers after exposure to particle rich or particle filtered air.This study indicates that exposure to air pollution particles at outdoor concentrations is not associated with detectable systemic inflammation, lipid or protein oxidation, altered haemostasis or microvascular function in young healthy participants.Epidemiological studies have consistently identified particulate matter (PM) in ambient air as an important risk factor for morbidity and mortality related to cardiovascular diseases [1]. The biological mechanisms of action of PM are thought to involve altered cardiac autonomic function, endothelial dysfunction, inflammation, oxidative stress, and altered blood hypercoaguability with small particles being more potent than larger particles due to their higher surface area and reactivity [2-4]. The ultrafine particle fraction of PM with a diameter of less than 100 nm and the ability to translocate through the epithelium of terminal bronchioles and alveoli is thought to be important in relation to health effects, although the extent of translocation has been debated [5,6]. Traffic-relat
Assessment of tissue oxygen saturation during a vascular occlusion test using near-infrared spectroscopy: the role of probe spacing and measurement site studied in healthy volunteers
Rick Bezemer, Alexandre Lima, Dean Myers, Eva Klijn, Michal Heger, Peter T Goedhart, Jan Bakker, Can Ince
Critical Care , 2009, DOI: 10.1186/cc8002
Abstract: StO2 was non-invasively measured in the forearm and thenar in eight healthy volunteers during 3-minute VOTs using two InSpectra tissue spectrometers equipped with a 15 mm probe or a 25 mm probe. VOT-derived StO2 traces were analyzed for base-line, ischemic, reperfusion, and hyperemic parameters. Data were categorized into four groups: 15 mm probe on the forearm (F15 mm), 25 mm probe on the forearm (F25 mm), 15 mm probe on the thenar (T15 mm), and 25 mm probe on the thenar (T25 mm).Although not apparent at baseline, probe spacing and measurement site significantly influenced VOT-derived StO2 variables. For F15 mm, F25 mm, T15 mm, and T25 mm, StO2 ownslope was -6.4 ± 1.7%/minute, -10.0 ± 3.2%/minute, -12.5 ± 3.0%/minute, and -36.7 ± 4.6%/minute, respectively. StO2 upslope was 105 ± 34%/minute, 158 ± 55%/minute, 226 ± 41%/minute, and 713 ± 101%/minute, and the area under the hyperemic curve was 7.4 ± 3.8%·minute, 10.1 ± 4.9%·minute, 12.6 ± 4.4%·minute, and 21.2 ± 2.7%·minute in these groups, respectively. Furthermore, the StO2 parameters of the hyperemic phase of the VOT, such as the area under the curve, significantly correlated to the minimum StO2 during ischemia.NIRS measurements in combination with a VOT are measurement site-dependent and probe-dependent. Whether this dependence is anatomy-, physiology-, or perhaps technology-related remains to be elucidated. Our study also indicated that reactive hyperemia depends on the extent of ischemic insult.It is now well established that tissue oxygen utilization and regional microcirculatory oxygen transport properties are severely affected during sepsis and shock [1-9]. To assess and identify these metabolic and microcirculatory alterations non-invasively, near-infrared spectroscopy (NIRS) has recently been applied to measure the behavior of tissue oxygen saturation (StO2). Besides observation of steady-state values, a vascular occlusion test (VOT) has been introduced for the measurement of tissue oxygen consumption and o
Glipizide Pharmacokinetics in Healthy and Diabetic Volunteers
M Atif, M Ahmad, M Qamar-uz-zaman, M Asif, SAS Sulaiman, AA Shafie, I Masood, U Minhas, N Us-saqib
Tropical Journal of Pharmaceutical Research , 2011,
Abstract: Purpose: Disease state may contribute to alteration in drug pharmacokinetics. The purpose of this study was to determine the effect of non-insulin dependent diabetes mellitus (NIDDM) on the pharmacokinetics of glipizide. Methods: An open, single-dose, parallel design was applied to the study. Glipizide tablet (5 mg) was administered to healthy and diabetic human volunteers after over-night fast. Blood samples were collected, centrifuged and the plasma assayed using a sensitive and validated reverse phase high performance liquid chromatography (RP-HPLC) method. Various pharmacokinetic parameters were computed from the data obtained. Results: The AUC0- values for healthy and diabetic volunteers was 1878 ± 195 and 1723 ± 138 ng.h/ml, respectively; these values were not significantly different (p > 0.05). The t1/2 for healthy volunteers was 3.04 ± 0.27 h while that for diabetic subjects was 2.98 ± 0.16 h. Clearance for healthy and diabetic volunteers was 0.59±0.06 and 0.64±0.05 ml/min/kg, respectively. These and other pharmacokinetic parameters assessed were not significantly different between healthy and diabetic volunteers (p > 0.05). Conclusion: Although glipizide showed slightly more rapid clearance from the body of diabetic volunteers than from healthy volunteers, this difference, like those for other pharmacokinetic parameters, was not significant (p > 0.05).
Exercise increases endostatin in circulation of healthy volunteers
Jian-Wei Gu, Giovani Gadonski, Julie Wang, Ian Makey, Thomas H Adair
BMC Physiology , 2004, DOI: 10.1186/1472-6793-4-2
Abstract: We examined treadmill exercise tests in healthy volunteers to determine the effect of exercise on plasma levels of endostatin and other angiogenic regulators. Oxygen consumption (VO2) was calculated. Plasma levels of endostatin, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) were determined using ELISA. The total peak VO2 (L) in 7 male subjects was 29.5 ± 17.8 over a 4–10 minute interval of exercise. Basal plasma levels of endostatin (immediately before exercise) were 20.3 ± 3.2 pg/ml, the plasma levels increased to 29.3 ± 4.2, 35.2 ± 1.8, and 27.1 ± 2.2 ng/ml, at 0.5, 2, and 6 h, respectively, after exercise. There was a strong linear correlation between increased plasma levels of endostatin (%) and the total peak VO2 (L) related to exercise (R2 = 0.9388; P < 0.01). Concurrently, VEGF levels decreased to 28.3 ± 6.4, 17.6 ± 2.4, and 26.5 ± 12.5 pg/ml, at 0.5, 2, and 6 h, respectively, after exercise. There were no significant changes in plasma bFGF levels in those subjects before and after exercise.The results suggest that circulating endostatin can be significantly increased by exercise in proportion to the peak oxygen consumption under physiological conditions in healthy volunteers. These findings may provide new insights into the molecular links between physical inactivity and the risk of angiogenesis dependent diseases such as atherosclerosis.Epidemiological data has established that physical inactivity increases the risk of many chronic diseases including atherosclerosis [1-3]. Coronary heart disease, ischemic stroke, and peripheral vascular disease are the clinical manifestations of atherosclerosis. Physical inactivity is believed to be an independent risk factor for the development of coronary heart disease [4], stroke [5], and peripheral vascular disease [6]. However, exercise can exert a beneficial influence on the risk factors for atherosclerosis by reducing hyperlipidemia, hypertension, obesity, platelet aggregability
Digestive tract microbiota in healthy volunteers
Zilberstein, Bruno;Quintanilha, Alina G;Santos, Manoel A A;Pajecki, Denis;Moura, Eduardo G;Alves, Paulo Roberto Arruda;Maluf Filho, Fauze;Souza, Jo?o Ary Ubriaco de;Gama-Rodrigues, Joaquim;
Clinics , 2007, DOI: 10.1590/S1807-59322007000100008
Abstract: purpose: the aim of this study was to standardize the methods of sample collection of mucus from the digestive tract and to determine the microbiota in healthy volunteers from brazil, collecting samples from the mouth, esophagus, stomach, duodenum, jejunum, ileum, colon, and rectum. methods: microbiota of selected healthy volunteers from the oral cavity (n=10), the esophagus (n=10), the upper digestive tract (n=20), and the lower digestive tract (n=24) were evaluated through distinct collection methods. collection methods took into account the different sites, using basic scraping and swabbing techniques, stimulated saliva from the oral cavity, irrigation-aspiration with sterile catheters especially designed for the esophagus, a probe especially designed for upper digestive tract, and a special catheter for the lower digestive tract. results: (i) mixed microbiota were identified in the oral cavity, predominantly gram-positive aerobic and anaerobic cocci; (ii) transitional flora mainly in the esophagus; (iii) veillonella sp, lactobacillus sp, and clostridium sp in the stomach and duodenum; (iv) in the jejunum and upper ileum, we observed bacteroides sp, proteus sp, and staphylococcus sp, in addition to veillonella sp; (v) in the colon, the presence of "nonpathogenic" anaerobic bacteria veillonella sp (average 105 ufc) indicates the existence of a low oxidation-reduction potential environment, which suggests the possibility of adoption of these bacteria as biological markers of total digestive tract health. conclusions: the collection methods were efficient in obtaining adequate samples from each segment of the total digestive tract to reveal the normal microbiota. these procedures are safe and easily reproducible for microbiological studies.
Pharmacokinetics of Oral Taurine in Healthy Volunteers  [PDF]
Mohammadreza Ghandforoush-Sattari,Siminozar Mashayekhi,Channarayapatna V. Krishna,John P. Thompson,Philipp A. Routledge
Journal of Amino Acids , 2010, DOI: 10.4061/2010/346237
Abstract: Taurine, a sulfur-containing amino acid, is a normal constituent of the human diet. Little is known of the pharmacokinetics of taurine in man after oral administration. We studied the pharmacokinetics of 4?g taurine in eight healthy male volunteers (median age 27.5, range 22–45) following orally administration in the fasting state in the morning. Blood samples were taken at regular intervals and plasma taurine concentration was measured by a modified HPLC method. Data were subjected to noncompartmental analysis. Maximum plasma taurine concentration ( ) was measured at ?hr after administration as ?mg/L ( ?mmol). Plasma elimination half-life ( ) and the ratio of clearance/bioavailability (Cl/F) were ?hr and ?L/hr, respectively. Since taurine is occasionally used in therapeutics as a medicine, the pharmacokinetics and effects of oral taurine in healthy volunteers would be useful in the future studies of taurine in pharmacology and nutrition. 1. Introduction Taurine, a sulfur-containing amino acid, is a relatively nontoxic substance and a normal constituent of the human diet [1]. The diet provides most taurine either directly or by synthesis in the liver and brain from methionine or cysteine via cysteic acid or hypotaurine [2] or via cysteamine in the heart and kidney. Taurine stabilises membranes, modulates calcium transport, and is able to dissipate the toxic effects of hypochlorous acid (HOCl) by the formation of the relatively stable taurochloramine molecule, generated by myeloperoxidases from oxygen radicals. The ability of taurine to conjugate with xenobiotics, retinoic acid, and bile salts and its role as a major free amino acid in regulating the osmolality of cells are also examples of protective functions [3]. Obinata et al. showed ALT concentrations recovering in children with fatty liver after 6-months treatment with oral taurine administered daily [4]. Protective effects of taurine against arteriosclerosis [5], lung injury by oxidant gases [6], deleterious effects of various drugs such as tauromustine, an antitumor agent, [7], hepatotoxicity of sulfolithocholate [8], and its promotion of the recovery of leukocytes in irradiated rats [9] have already been studied on animals. The therapeutic effects of taurine on epilepsy [10], ischemia [11], obesity [12], diabetes [13], hypertension [14], Congestive heart failure [15], noxious effect of smoking [16], toxicity of methotrexate [17] myocardial infarction [18], alcoholic craving [19], and neurodegeneration in elderly [20] have also been reported. Taurine may protect membranes by detoxification of
Prediction of pain sensitivity in healthy volunteers
Ravn P, Frederiksen R, Skovsen AP, Christrup LL, Werner MU
Journal of Pain Research , 2012, DOI: http://dx.doi.org/10.2147/JPR.S33925
Abstract: ediction of pain sensitivity in healthy volunteers Original Research (1337) Total Article Views Authors: Ravn P, Frederiksen R, Skovsen AP, Christrup LL, Werner MU Published Date August 2012 Volume 2012:5 Pages 313 - 326 DOI: http://dx.doi.org/10.2147/JPR.S33925 Received: 16 May 2012 Accepted: 21 July 2012 Published: 29 August 2012 Pernille Ravn,1 Rune Frederiksen,2 Anders P Skovsen,3 Lona L Christrup,1 Mads U Werner2 1Department of Drug Design and Pharmacology, University of Copenhagen, 2Multidisciplinary Pain Center, Neuroscience Center, Rigshospitalet, Copenhagen University Hospital, 3Department of Surgery, Koge Hospital, Copenhagen University Hospital, Copenhagen, Denmark Purpose: The primary objective of the present study was to evaluate predictive parameters of the acute pain score during induction of an inflammatory heat injury. Patients and methods: Healthy volunteers (50 females/50 males) were included in the study. The predictive potential of gender, anthropometric (body surface area, body mass index), psychological (anxiety, depression, vulnerability), and psychophysical (quantitative sensory testing, conditioned pain modulation) variables in estimating the pain response to a validated heat injury (47°C, 7 minutes, area 12.5 cm2) were investigated. All assessments were made in duplicate sessions separated by 21 days (median). Results: There were three main findings in this study. First, a predictive model of pain sensitivity during the heat injury, including both genders and using multiple regression technique, could account for 28% of the variance (P < 0.0001), but gender-related differences in the final model could not be demonstrated. Second, the results confirmed significant gender-related differences in perception of electrical, pressure, and cold pressor stimuli (P < 0.002). Third, positive correlations between anthropometric data and pain perception during electrical and pressure stimuli were demonstrated (P < 0.001 and P < 0.005, respectively). Conclusion: The study demonstrated predictability of acute pain sensitivity, and although gender-related differences in pain perception were demonstrated, no gender-related differences in pain sensitivity could be shown. Interestingly, positive correlations between anthropometric data and pain perception were shown for the first time.
Prediction of pain sensitivity in healthy volunteers  [cached]
Ravn P,Frederiksen R,Skovsen AP,Christrup LL
Journal of Pain Research , 2012,
Abstract: Pernille Ravn,1 Rune Frederiksen,2 Anders P Skovsen,3 Lona L Christrup,1 Mads U Werner21Department of Drug Design and Pharmacology, University of Copenhagen, 2Multidisciplinary Pain Center, Neuroscience Center, Rigshospitalet, Copenhagen University Hospital, 3Department of Surgery, Koge Hospital, Copenhagen University Hospital, Copenhagen, DenmarkPurpose: The primary objective of the present study was to evaluate predictive parameters of the acute pain score during induction of an inflammatory heat injury.Patients and methods: Healthy volunteers (50 females/50 males) were included in the study. The predictive potential of gender, anthropometric (body surface area, body mass index), psychological (anxiety, depression, vulnerability), and psychophysical (quantitative sensory testing, conditioned pain modulation) variables in estimating the pain response to a validated heat injury (47°C, 7 minutes, area 12.5 cm2) were investigated. All assessments were made in duplicate sessions separated by 21 days (median).Results: There were three main findings in this study. First, a predictive model of pain sensitivity during the heat injury, including both genders and using multiple regression technique, could account for 28% of the variance (P < 0.0001), but gender-related differences in the final model could not be demonstrated. Second, the results confirmed significant gender-related differences in perception of electrical, pressure, and cold pressor stimuli (P < 0.002). Third, positive correlations between anthropometric data and pain perception during electrical and pressure stimuli were demonstrated (P < 0.001 and P < 0.005, respectively).Conclusion: The study demonstrated predictability of acute pain sensitivity, and although gender-related differences in pain perception were demonstrated, no gender-related differences in pain sensitivity could be shown. Interestingly, positive correlations between anthropometric data and pain perception were shown for the first time.Keywords: experimental pain, gender differences, healthy subjects, prediction, quantitative sensory testing
The OxyMask development and performance in healthy volunteers
James E Paul, Horia Hangan, Julius Hajgato
Medical Devices: Evidence and Research , 2009, DOI: http://dx.doi.org/10.2147/MDER.S4376
Abstract: sk development and performance in healthy volunteers Original Research (10405) Total Article Views Authors: James E Paul, Horia Hangan, Julius Hajgato Published Date December 2008 Volume 2009:2 Pages 9 - 17 DOI: http://dx.doi.org/10.2147/MDER.S4376 James E Paul1, Horia Hangan2, Julius Hajgato3 1Department of Anesthesia, McMaster University, Hamilton, ON, Canada; 2Faculty of Engineering, The University of Western Ontario, London, ON, Canada; 3Southmedic Inc., Barrie, ON, Canada Background: The OxyMask is a unique, open-style, oxygen mask that was originally developed in 2005. The original mask was modified, using computational fluid dynamics numerical simulations, with the goal of allowing it to produce a wider range of FiO2. This analysis was used to guide the modification of the mask shell and the location for the oxygen diffuser. Methods: The new OxyMask was attached to 10 healthy subjects and used to deliver escalating levels of oxygen (1.5, 2, 2.5, 3, 5, 10, 15, 20, 25 and 30 LPM) for 90 seconds at each level and the resulting FiO2 was recorded (at the lips) from 5 consecutive measurements at each oxygen flow rate. Results: Mean FiO2 was 25.4% at 1.5 LPM of oxygen, 30.1% at 2 LPM, 36.5% at 2.5 LPM, 41.8% at 3 LPM, 57.6% at 5 LPM, 74.4% at 10 LPM, and 80.1% at 15 LPM. Each FiO2 achieved at these escalating oxygen levels was significantly greater than all the previous levels. The mean FiO2 was 82.8 at 20 LPM, 84.2% at 25 LPM and 84.3% at 30 LPM. All of these values on average were not significantly greater than the FiO2 achieved with 15 LPM. In a few subjects a maximum FiO2 of 90% was reached. Conclusion: The original OxyMask was successfully modified so that the second generation of the mask can provide a wide range of FiO2, from 25% to 90%, while keeping its unique open design.
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