Trees on K-12 School Campuses in Virginia

Trees and saplings growing on K-12 school campuses were investigated in 105 school districts across Virginia. There were 2812 trees (\u3e12.5 cm stem diameter at 1.4 m above ground level) inventoried across all campuses. The mean and median campus tree population was 27 and 18, respectively. Loblolly pine (Pinus taeda L.) was the most abundant species, accounting for 11% of all inventoried trees. Red maple (Acer rubrum L.) was the most frequently inventoried species, present on 44% of the campuses. Sapling (trees with 2.5-12.5 cm stem diameter at 1.4 m above ground level) populations were similar to tree populations. The mean and median campus sapling population was 23 and 13, respectively. Flowering dogwood (Cornus florida L.) and red maple were the most abundant sapling species, each accounting for about 10% of all inventoried saplings. Flowering dogwood, red maple, Bradford pear (Pyrus calleryana Decne. ‘Bradford’), willow oak (Quercus phellos L. ), and ornamental cherry (Prunus spp. ) were the most frequently inventoried sapling species, each present on more than 25% of the campuses. Across all campuses, species diversity was relatively low: less than 10 species accounted for over 50% of the inventoried trees and saplings. Prominent Virginia natives, in particular Carya and Quercus species, were under represented in the inventory

Evidence of mononuclear cell preactivation in the fasting state in polycystic ovary syndrome

OBJECTIVE: We evaluated mononuclear cell (MNC) preactivation in women with polycystic ovary syndrome (PCOS) by examining the effect of in vitro lipopolysaccharide (LPS) exposure on cytokine release in the fasting state. STUDY DESIGN: Twenty women with PCOS (10 lean, 10 obese) and 20 weight-matched controls (10 lean, 10 obese) volunteered for study participation. Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release was measured from mononuclear cells isolated from fasting blood samples and cultured in the presence and absence of LPS. Plasma IL-6 was measured from the same fasting blood samples. Insulin sensitivity was derived from an oral glucose tolerance test using the Matsuda index, and truncal fat was measured by dual-energy x-ray absorptiometry. RESULTS: The percent change from baseline in TNF-α and IL-6 release from MNC following LPS exposure was increased (P < .04) in lean and obese women with PCOS and obese controls compared with lean controls. Plasma IL-6 was increased (P < .02) in obese women with PCOS compared with lean women with PCOS, which in turn was increased (P < .02) compared with lean controls. The MNC-derived TNF-α and IL-6 responses from MNCs were negatively correlated with insulin sensitivity (P < .03) and positively correlated with testosterone (P < .03) and androstenedione (P < .006) for the combined groups. Plasma IL-6 was positively correlated with percentage truncal fat (P < .008). CONCLUSION: In PCOS, increased cytokine release from MNCs following LPS exposure in the fasting state reveals the presence of MNC preactivation. Importantly, this phenomenon is independent of obesity and may contribute to the development of insulin resistance and hyperandrogenism in PCOS. In contrast, the source of plasma IL-6 elevations in PCOS may be excess adiposity

Adiposity measures, lean body mass, physical activity and mortality: NHANES 1999–2004

BACKGROUND: Obesity and physical inactivity are major public health problems. We studied the associations between measures of adiposity, lean body mass, leisure time physical activity (LTPA), and death in those with and without chronic kidney disease (CKD). METHODS: Associations between body mass index (BMI), waist circumference (WC), percent body fat, lean body mass (assessed with Dual-Energy X-ray Absorptiometry[DEXA]), leisure time physical activity (LTPA) and death were examined using the National Health and Nutrition Examination Surveys (NHANES 1999–2004). All-cause mortality was ascertained by linkage of NHANES files with the National Death Index. RESULTS: 9,433 non-CKD participants and 2,153 CKD participants who had fat mass measured using DEXA, BMI, WC, LTPA and mortality data were included. After adjusting for demographics, comorbid conditions, kidney function measures, C-Reactive Protein (CRP), and sodium intake there was no significant risk for death noted with higher WC, fat mass and BMI in those with and without CKD. When examining normal, overweight, and obese groups based on BMI criteria, being overweight (BMI 25–29.9 kg/m(2)) was associated with lower risk of death in those without CKD (Hazard ratio 0.62, 95% CI 0.40, 0.95). Higher lean body mass was associated with lower risk for death in those without kidney disease but not in the CKD population. There was a significantly higher risk for death among those who did not meet the minimum LTPA goals compared to those who met or exceeded the recommended activity levels (>450 MET/min/week) in those with and without CKD (CKD Hazard ratio: 1.36, 95% CI 1.003, 1.85; non-CKD HR 1.65, 95% CI 1.21, 2.26). CONCLUSIONS: In a representative sample of the US population, higher LTPA levels and lean body mass were associated with lower mortality in those without kidney disease. In CKD, higher LTPA was associated with lower risk of death. There was no association between adiposity measures and death in those with and without CKD except for lower mortality associated with overweight among those without CKD. The data suggests the need to develop programs to facilitate an increase in physical activity in people with and without kidney disease

Glucose and lipopolysaccharide regulate proatherogenic cytokine release from mononuclear cells in polycystic ovary syndrome

Women with polycystic ovary syndrome (PCOS) have chronic low-grade inflammation, which can increase the risk of atherogenesis. We examined the effect of glucose ingestion and lipopolysaccharide (LPS) on markers of proatherogenic inflammation in the mononuclear cells (MNC) and plasma of women with PCOS. Sixteen women with PCOS (8 lean, 8 obese) and 15 weight-matched controls (8 lean, 7 obese) underwent a 3-h oral glucose tolerance test (OGTT). Interleukin-6 (IL-6) and interleukin-1β (IL-1β) release from MNC cultured in the presence of LPS and plasma IL-6, C-reactive protein (CRP), and soluble vascular adhesion molecule-1 (sVCAM-1) were measured from blood samples drawn while fasting and 2 h after glucose ingestion. Truncal fat was measured by dual-energy absorptiometry (DEXA). Lean women with PCOS and obese controls failed to suppress LPS-stimulated IL-6 and IL-1β release from MNC after glucose ingestion. In contrast, obese women with PCOS suppressed these MNC-derived cytokines under the same conditions. In response to glucose ingestion, plasma IL-6 and sVCAM-1 increased and CRP suppression was attenuated in both PCOS groups and obese controls compared with lean controls. Fasting plasma IL-6 and CRP correlated positively with percentage of truncal fat. The absolute change in plasma IL-6 correlated positively with testosterone. We conclude that glucose ingestion promotes proatherogenic inflammation in PCOS with a systemic response that is independent of obesity. Based on the suppressed MNC-derived cytokine responses suggestive of LPS tolerance, chronic low-grade inflammation may be more profound in obese women with PCOS. Excess abdominal adiposity and hyperandrogenism may contribute to atherogenesis in PCOS

Physiological and metabolic characteristics of elite tug of war athletes

Objective—To determine the aerobic power ([Image: see text] O(2)MAX), body composition, strength, muscular power, flexibility, and biochemical profile of an elite international squad of tug of war athletes. Methods—Sixteen male competitors (mean (SEM) age 34 (2) years) were evaluated in a laboratory. For comparative purposes, data were analysed relative to normative data for our centre and to a group of 20 rugby forwards from the Irish international squad. Results—The tug of war participants were lighter (83.6 (3.0) v 104.4 (1.8) kg, p<0.0001) and had less lean body mass (69.4 (2.1) v 86.2 (1.2) kg) than the rugby players and had lower than normal body fat (16.7 (0.9)%); all values are mean (SEM). Aerobic power measured during a treadmill test was 55.8 (1.6) ml/kg/min for the tug of war participants compared with 51.1 (1.4) ml/kg/min for the rugby forwards (p<0.03). A composite measure of strength derived from (sum of dominant and non-dominant grip strength and back strength)/lean body mass yielded a strength/mass ratio that was 32% greater (p<0.0001) for the tug of war group than the rugby group. Dynamic leg power was lower for the tug of war group than the rugby forwards (4659.8 (151.6) v 6198.2 (105) W respectively; p<0.0001). Leg flexibility was 25.4 (2.0) cm for the tug of war group. Back flexibility was 28.6 (1.4) cm which was lower (p<0.02) than the rugby forwards 34.2 (1.5) cm. Whereas blood chemistry and haematology were normal, packed cell volume, haemoglobin concentration, and erythrocyte volume were lower in the tug of war group than in the rugby players (p<0.05). All three haematological measures correlated with muscle mass (packed cell volume, r(2) = 0.37, p<0.0001; haemoglobin concentration, r(2) = 0.13, p<0.05; erythrocyte volume, r(2) = 0.21, p<0.01). Conclusions—The data indicate that international level tug of war participants have excellent strength and above average endurance relative to body size, but have relatively low explosive leg power and back flexibility. The data provide reference standards for the sport and may be useful for monitoring and evaluating current and future participants. Key Words: tug of war; body composition; [Image: see text] O(2)MAX; strength; power; flexibilit

Control of the Oxygen Dependence of an Implantable Polymer/Enzyme Composite Biosensor for Glutamate

Biosensors for glutamate (Glu) were fabricated from Teflon-coated Pt wire (cylinders and disks), modified with the enzyme glutamate oxidase (GluOx) and electrosynthesized polymer PPD, poly(o-phenylenediamine). The polymer/enzyme layer was deposited in two configurations:  enzyme before polymer (GluOx/PPD) and enzyme after polymer (PPD/GluOx). These four biosensor designs were characterized in terms of response time, limit of detection, Michaelis−Menten parameters for Glu (Jmax and KM(Glu)), sensitivity to Glu in the linear response region, and dependence on oxygen concentration, KM(O2). Analysis showed that the two polymer/enzyme configurations behaved similarly on both cylinders and disks. Although the two geometries showed different behaviors, these differences could be explained in terms of higher enzyme loading density on the disks; in many analyses, the four designs behaved like a single population with a range of GluOx loading. Enzyme loading was the key to controlling the KM(O2) values of these first generation biosensors. The counterintuitive, and beneficial, behavior that biosensors with higher GluOx loading displayed a lower oxygen dependence was explained in terms of the effects of enzyme loading on the affinity of GluOx for its anionic substrate. Some differences between the properties of surface immobilized GluOx and glucose oxidase are highlighted

The efficiency of immobilised glutamate oxidase decreases with surface enzyme loading: an electrostatic effect, and reversal by a polycation significantly enhances biosensor sensitivity

The apparent Michaelis constant, KM, for glutamate oxidase (GluOx) immobilised on Pt electrodes increased systematically with enzyme loading. The effect was due, at least in part, to electrostatic repulsion between neighbouring oxidase molecules and the anionic substrate, glutamate (Glu). This understanding has allowed us to increase the Glu sensitivity of GluOx-based amperometric biosensors in the linear response region (100 ± 11 nA cmâ2µMâ1 at pH 7.4; SD, n = 23) by incorporating a polycation (polyethyleneimine, PEI) to counterbalance the polyanionic protein. Differences in the behaviour of glucose biosensors of a similar configuration highlight a limitation of using glucose oxidase as a model enzyme in biosensor design

The efficiency of immobilised glutamate oxidase decreases with surface enzyme loading: an electrostatic effect, and reversal by a polycation significantly enhances biosensor sensitivity

The apparent Michaelis constant, KM, for glutamate oxidase (GluOx) immobilised on Pt electrodes increased systematically with enzyme loading. The effect was due, at least in part, to electrostatic repulsion between neighbouring oxidase molecules and the anionic substrate, glutamate (Glu). This understanding has allowed us to increase the Glu sensitivity of GluOx-based amperometric biosensors in the linear response region (100 ± 11 nA cmâ2µMâ1 at pH 7.4; SD, n = 23) by incorporating a polycation (polyethyleneimine, PEI) to counterbalance the polyanionic protein. Differences in the behaviour of glucose biosensors of a similar configuration highlight a limitation of using glucose oxidase as a model enzyme in biosensor design

Mitochondrial Utilization of Competing Fuels is Altered in Insulin Resistant Skeletal Muscle of Non-Obese Rats (Goto-Kakizaki)

Aim: Insulin-resistant skeletal muscle is characterized by metabolic inflexibility with associated alterations in substrate selection, mediated by peroxisome-proliferator activated receptor (PPAR). Although it is established that PPAR contributes to the alteration of energy metabolism, it is not clear whether it plays a role in mitochondrial fuel competition. While nutrient overload may impair metabolic flexibility by fuel congestion within mitochondria, in absence of obesity defects at a mitochondrial level have not yet been excluded. We sought to determine whether reduced PPAR content in insulin-resistant rat skeletal muscle of a non-obese rat model of T2DM (Goto-Kakizaki, GK) ameliorate the inhibitory effect of fatty acid (i.e., palmitoylcarnitine) on mitochondrial carbohydrate oxidization (i.e., pyruvate) in muscle fibers. Methods: Bioenergetic function was characterized in oxidative soleus (S) and glycolytic white gastrocnemius (WG) muscles with measurement of respiration rates in permeabilized fibers in the presence of complex I, II, IV, and fatty acid substrates. Mitochondrial content was measured by citrate synthase (CS) and succinate dehydrogenase activity (SDH). Western blot was used to determine protein expression of PPAR, PDK isoform 2 and 4. Results: CS and SDH activity, key markers of mitochondrial content, were reduced by similar to 10-30% in diabetic vs. control, and the effect was evident in both oxidative and glycolytic muscles. PPAR (p\u3c 0.01), PDK2 (p\u3c 0.01), and PDK4 (p= 0.06) protein content was reduced in GK animals compared to Wistar rats (N= 6 per group). Ex vivorespiration rates in permeabilized muscle fibers determined in the presence of complex I, II, IV, and fatty acid substrates, suggested unaltered mitochondrial bioenergetic function in T2DM muscle. Respiration in the presence of pyruvate was higher compared to palmitoylcarnitine in both animal groups and fiber types. Moreover, respiration rates in the presence of both palmitoylcarnitine and pyruvate were reduced by 25 ± 6% (S), 37 ± 6% (WG) and 63 ± 6% (S), 57 ± 8% (WG) compared to pyruvate for both controls and GK, respectively. The inhibitory effect of palmitoylcarnitine on respiration was significantly greater in GK than controls (p \u3c 10-3). Conclusion: With competing fuels, the presence of fatty acids diminishes mitochondria ability to utilize carbohydrate derived substrates in insulin-resistant muscle despite reduced PPAR delta content