11 research outputs found
Effect of the dietary supplement Meltdown on catecholamine secretion, markers of lipolysis, and metabolic rate in men and women: a randomized, placebo controlled, cross-over study
<p>Abstract</p> <p>Background</p> <p>We have recently reported that the dietary supplement Meltdown<sup>® </sup>increases plasma norepinephrine (NE), epinephrine (EPI), glycerol, free fatty acids (FFA), and metabolic rate in men. However, in that investigation measurements ceased at 90 minutes post ingestion, with values for blood borne variables peaking at this time. It was the purpose of the present investigation to extend the time course of measurement to 6 hours, and to include women within the design to determine if sex differences to treatment exist.</p> <p>Methods</p> <p>Ten men (24 ± 4 yrs) and 10 women (22 ± 2 yrs) ingested Meltdown<sup>® </sup>or a placebo, using a randomized, cross-over design with one week separating conditions. Blood samples were collected immediately before supplementation and at one hour intervals through 6 hours post ingestion. A standard meal was provided after the hour 3 collection. Samples were assayed for EPI, NE, glycerol, and FFA. Five minute breath samples were collected at each time for measurement of metabolic rate and substrate utilization. Area under the curve (AUC) was calculated. Heart rate and blood pressure were recorded at all times. Data were also analyzed using a 2 (sex) × 2 (condition) × 7 (time) repeated measures analysis of variance, with Tukey <it>post hoc </it>testing.</p> <p>Results</p> <p>No sex × condition interactions were noted for AUC for any variable (p > 0.05). Hence, AUC data are collapsed across men and women. AUC was greater for Meltdown<sup>® </sup>compared to placebo for EPI (367 ± 58 pg·mL<sup>-1</sup>·6 hr<sup>-1 </sup>vs. 183 ± 27 pg·mL<sup>-1</sup>·6 hr<sup>-1</sup>; p = 0.01), NE (2345 ± 205 pg·mL<sup>-1</sup>·6 hr<sup>-1 </sup>vs. 1659 ± 184 pg·mL<sup>-1</sup>·6 hr<sup>-1</sup>; p = 0.02), glycerol (79 ± 8 μg·mL<sup>-1</sup>·6 hr<sup>-1 </sup>vs. 59 ± 6 μg·mL<sup>-1</sup>·6 hr<sup>-1</sup>; p = 0.03), FFA (2.46 ± 0.64 mmol·L<sup>-1</sup>·6 hr<sup>-1 </sup>vs. 1.57 ± 0.42 mmol·L<sup>-1</sup>·6 hr<sup>-1</sup>; p = 0.05), and kilocalorie expenditure (439 ± 26 kcal·6 hrs<sup>-1 </sup>vs. 380 ± 14 kcal·6 hrs<sup>-1</sup>; p = 0.02). No effect was noted for substrate utilization (p = 0.39). Both systolic and diastolic blood pressure (p < 0.0001; 1–16 mmHg), as well as heart rate (p = 0.01; 1–9 bpm) were higher for Meltdown<sup>®</sup>. No sex × condition × time interactions were noted for any variable (p > 0.05).</p> <p>Conclusion</p> <p>Ingestion of Meltdown<sup>® </sup>results in an increase in catecholamine secretion, lipolysis, and metabolic rate in young men and women, with a similar response for both sexes. Meltdown<sup>® </sup>may prove to be an effective intervention strategy for fat loss, assuming individuals are normotensive and their treatment is monitored by a qualified health care professional.</p
Ultrafast Excited State Relaxation of a Metalloporphyrin Revealed by Femtosecond X-ray Absorption Spectroscopy
Photoexcited Nickel(II) tetramesitylporphyrin
(NiTMP), like many
open-shell metalloporphyrins, relaxes rapidly through multiple electronic
states following an initial porphyrin-based excitation, some involving
metal centered electronic configuration changes that could be harnessed
catalytically before excited state relaxation. While a NiTMP excited
state present at 100 ps was previously identified by X-ray transient
absorption (XTA) spectroscopy at a synchrotron source as a relaxed
(d,d) state, the lowest energy excited state (<i>J. Am. Chem.
Soc.</i>, <b>2007</b>, <i>129</i>, 9616 and <i>Chem. Sci.</i>, <b>2010</b>, <i>1</i>, 642),
structural dynamics before thermalization were not resolved due to
the ∼100 ps duration of the available X-ray probe pulse. Using
the femtosecond (fs) X-ray pulses of the Linac Coherent Light Source
(LCLS), the Ni center electronic configuration from the initial excited
state to the relaxed (d,d) state has been obtained via ultrafast Ni
K-edge XANES (X-ray absorption near edge structure) on a time scale
from hundreds of femtoseconds to 100 ps. This enabled the identification
of a short-lived Ni(I) species aided by time-dependent density functional
theory (TDDFT) methods. Computed electronic and nuclear structure
for critical excited electronic states in the relaxation pathway characterize
the dependence of the complex’s geometry on the electron occupation
of the 3d orbitals. Calculated XANES transitions for these excited
states assign a short-lived transient signal to the spectroscopic
signature of the Ni(I) species, resulting from intramolecular charge
transfer on a time scale that has eluded previous synchrotron studies.
These combined results enable us to examine the excited state structural
dynamics of NiTMP prior to thermal relaxation and to capture intermediates
of potential photocatalytic significance
Effect of Ambrotose AO® on resting and exercise-induced antioxidant capacity and oxidative stress in healthy adults
<p>Abstract</p> <p>Background</p> <p>The purpose of this investigation was to determine the effects of a dietary supplement (Ambrotose AO<sup>®</sup>) on resting and exercise-induced blood antioxidant capacity and oxidative stress in exercise-trained and untrained men and women.</p> <p>Methods</p> <p>25 individuals (7 trained and 5 untrained men; 7 trained and 6 untrained women) received Ambrotose AO<sup>® </sup>(4 capsules per day = 2 grams per day) or a placebo for 3 weeks in a random order, double blind cross-over design (with a 3 week washout period). Blood samples were collected at rest, and at 0 and 30 minutes following a graded exercise treadmill test (GXT) performed to exhaustion, both before and after each 3 week supplementation period. Samples were analyzed for Trolox Equivalent Antioxidant Capacity (TEAC), Oxygen Radical Absorbance Capacity (ORAC), malondialdehyde (MDA), hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), and nitrate/nitrite (NOx). Quality of life was assessed using the SF-12 form and exercise time to exhaustion was recorded. Resting blood samples were analyzed for complete blood count (CBC), metabolic panel, and lipid panel before and after each 3 week supplementation period. Dietary intake during the week before each exercise test was recorded.</p> <p>Results</p> <p>No condition effects were noted for SF-12 data, for GXT time to exhaustion, or for any variable within the CBC, metabolic panel, or lipid panel (p > 0.05). Treatment with Ambrotose AO<sup>® </sup>resulted in an increase in resting levels of TEAC (p = 0.02) and ORAC (p < 0.0001). No significant change was noted in resting levels of MDA, H<sub>2</sub>O<sub>2</sub>, or NOx (p > 0.05). Exercise resulted in an acute increase in TEAC, MDA, and H<sub>2</sub>O<sub>2 </sub>(p < 0.05), all which were higher at 0 minutes post exercise compared to pre exercise (p < 0.05). No condition effects were noted for exercise related data (p > 0.05), with the exception of ORAC (p = 0.0005) which was greater at 30 minutes post exercise for Ambrotose AO<sup>® </sup>compared to placebo.</p> <p>Conclusion</p> <p>Ambrotose AO<sup>® </sup>at a daily dosage of 4 capsules per day increases resting blood antioxidant capacity and may enhance post exercise antioxidant capacity. However, no statistically detected difference is observed in resting or exercise-induced oxidative stress biomarkers, in quality of life, or in GXT time to exhaustion.</p
Ultrafast Excited State Relaxation of a Metalloporphyrin Revealed by Femtosecond Xray Absorption Spectroscopy
Community-Led Economic Initiatives with Sex Workers: Establishing a Conceptual Framework for a Multidimensional Structural Intervention
Effects of the H3 antagonist, thioperamide, on behavioral alterations induced by systemic MK-801 administration in rats
Electronic and Nuclear Structural Snapshots in Ligand Dissociation and Recombination Processes of Iron Porphyrin in Solution: A Combined Optical/X-ray Approach
Initial invasive or conservative strategy for stable coronary disease
BACKGROUND Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, 121.8 percentage points; 95% CI, 124.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used