The associations between cardiovascular and pain responses to a cold pressor test differ between males and females.

Nociceptors contribute to the cardiovascular responses during a cold pressor test (CPT). While these responses are lower in females, data suggest that they perceive the CPT as more painful. Thus, we examined sex differences in associations between pain and cardiovascular responses to a CPT (Aim 1) as well as differences between females using (OC), and not using (NC), an oral contraceptive (Aim 2).

Acute sympathetic activation blunts the hyperemic and vasodilatory response to passive leg movement.

Heightened muscle sympathetic nerve activity (MSNA) contributes to impaired vasodilatory capacity and vascular dysfunction associated with aging and cardiovascular disease. The contribution of elevated MSNA to the vasodilatory response during passive leg movement (PLM) has not been adequately addressed. This study sought to test the hypothesis that elevated MSNA diminishes the vasodilatory response to PLM in healthy young males (n = 11, 25 ± 2 year).

Muscle blood flow and vasodilation are blunted at the onset of exercise following an acute bout of ischemia-reperfusion.

Ischemia-reperfusion (I/R) injury can attenuate endothelial function and impair nitric oxide bioavailability. We tested the hypothesis that I/R also blunts the rapid and steady-state hyperemic and vasodilatory responses to handgrip exercise. Ten subjects (8M/2F; 24 ± 4 yr) performed handgrip exercises before and after I/R (20 min of ischemia/20 min of reperfusion) and time control (40-min supine rest) trials.

Intermittent versus continuous handgrip exercise and peripheral endothelial function: impact of shear rate fluctuations.

Sustained exercise-induced elevations in shear rate (SR) have been well established as beneficial for improving endothelial function. However, the impact of intermittent fluctuations in SR is not understood. We investigated the effect of intermittent SR elevations compared with sustained elevations on peripheral endothelial function.

Eight weeks of inorganic nitrate/nitrite supplementation improves aerobic exercise capacity and the gas exchange threshold in patients with type 2 diabetes.

Patients with type 2 diabetes mellitus (T2DM) have reduced exercise capacity, indexed by lower maximal oxygen consumption (V̇o) and achievement of the gas exchange threshold (GET) at a lower % V̇o. The ubiquitous signaling molecule nitric oxide (NO) plays a multifaceted role during exercise and, as patients with T2DM have poor endogenous NO production, we investigated if inorganic nitrate/nitrite supplementation (an exogenous source of NO) improves exercise capacity in patients with T2DM. Thirty-six patients with T2DM (10F, 59 ± 9 yr, 32.

Hypoxia offsets the decline in brachial artery flow-mediated dilation after acute inactivity.

Intermittent (IH), as opposed to continuous hypoxia (CH), is thought to have beneficial effects on cardiovascular function and health. In the present study, we examined the acute effects of IH and CH (∼80% pulse oxygen saturation via 10% oxygen tank) on peripheral vascular function. Brachial artery flow-mediated dilation (FMD) was used to assess vascular function in 12 young adults (23 ± 5 yr; 8 M/4 F) before and after 50 min of IH (5 cycles; 4-min normoxia/6-min hypoxia per cycle), CH (20-min normoxia followed by 30-min hypoxia), or time control (50-min normoxia) interventions.

Impact of Interrepetition Rest on Muscle Blood Flow and Exercise Tolerance during Resistance Exercise.

Background and Objectives: Muscle blood flow is impeded during resistance exercise contractions, but immediately increases during recovery. The purpose of this study was to determine the impact of brief bouts of rest (2 s) between repetitions of resistance exercise on muscle blood flow and exercise tolerance. Materials and Methods: Ten healthy young adults performed single-leg knee extension resistance exercises with no rest between repetitions (i.

Acute inorganic nitrate supplementation and the hypoxic ventilatory response in patients with obstructive sleep apnea.

Patients with obstructive sleep apnea (OSA) have increased cardiovascular disease risk largely attributable to hypertension. Heightened peripheral chemoreflex sensitivity (i.e.

Indices of leg resistance artery function are independently related to cycling V̇O max.

Purpose: While maximum blood flow influences one's maximum rate of oxygen consumption (V̇O max), with so many indices of vascular function, it is still unclear if vascular function is related to V̇O max in healthy, young adults. The purpose of this study was to determine if several common vascular tests of conduit artery and resistance artery function provide similar information about vascular function and the relationship between vascular function and V̇O max.

Methods: Twenty-two healthy adults completed multiple assessments of leg vascular function, including flow-mediated dilation (FMD), reactive hyperemia (RH), passive leg movement (PLM), and rapid onset vasodilation (ROV).

Intermittent hypoxia enhances shear-mediated dilation of the internal carotid artery in young adults.

Cyclic intermittent hypoxia (IH) increases cerebral blood velocity. This enhanced velocity augments the commensurate shear stimulus and may subsequently increase cerebrovascular endothelial function. This study aimed to examine the effects of cyclic IH on hypercapnia-induced shear-mediated dilation of the internal carotid artery (ICA), a potential index of cerebrovascular endothelial function.

Vascular function is related to blood flow during high-intensity, but not low-intensity, knee extension exercise.

While vascular function, assessed as the ability of the vasculature to dilate in response to a stimulus, is related to cardiovascular health, its relationship to exercise hyperemia is unclear. This study sought to determine if blood flow during submaximal and maximal exercise is related to vascular function. Nineteen healthy adults completed multiple assessments of vascular function specific to the leg, including passive leg movement (PLM), rapid onset vasodilation (ROV), reactive hyperemia (RH), and flow-mediated dilation (FMD).

The effect of the speed and range of motion of movement on the hyperemic response to passive leg movement.

Passive leg movement (PLM)-induced hyperemia is used to assess the function of the vascular endothelium. This study sought to determine the impact of movement speed and range of motion (ROM) on the hyperemic response to PLM and determine if the currently recommended protocol of moving the leg through a 90° ROM at 180°/sec provides a peak hyperemic response to PLM. 11 healthy adults underwent multiple bouts of PLM, in which either movement speed (60-240°/sec) or ROM (30-120° knee flexion) were varied.

Constitutive expression of a high-affinity sulfate transporter in Indian mustard affects metal tolerance and accumulation.

The Stylosanthes hamata SHST1 gene encodes a high-affinity sulfate transporter located in the plasma membrane. In this study the S. hamata SHST1 gene was constitutively expressed in Indian mustard [Brassica juncea (L.

Neptunium(V) partitioning to uranium(VI) oxide and peroxide solids.

Metaschoepite, [(UO2)8O2(OH)12] x 10H2O, and metastudtite, UO4 x 4H2O, are alteration phases anticipated in a spent nuclear fuel repository following the moist oxidation of UO2 on a geologic time scale. Dissolved concentrations and hence potential mobility of other radionuclides in the fuel, such as the neptunyl cation (NpO2+), will likely be determined by the extent of their partitioning into these U(VI) solids. 237Np is of particular interest due to its potential high mobility and long half-life (2.

Selenium protects plants from phloem-feeding aphids due to both deterrence and toxicity.

•  Certain plant species hyperaccumulate selenium (Se) to 1000 mg kg d. wt, even from low-Se soils. It is not known whether Se hyperaccumulation offers these plants any advantage.

Selenium accumulation protects Brassica juncea from invertebrate herbivory and fungal infection.

•  Certain plant species hyperaccumulate selenium (Se) up to 0.6% of their dry weight. It is not known whether Se hyperaccumulation offers the plants any advantage.