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Objective: We examined whether the ingestion of a hydrothermally modified starch (HMS) would alter metabolic and hormonal responses to prolonged cycling compared with maltodextrin (MAL). Methods: Nine male cyclists (30 � 2y , 79.2� 2.1 kg, 4.7 � 0.1 L of O2/min, 7.5 � 1.3 y training) fasted 10 h before cycling for 150 min at 70% peak oxygen consumption and completing a cyclingto-exhaustion trial at 100% peak oxygen consumption. Participants ingested 1g/kg of HMS or MAL 30 min before and within 10 min of completing the bout. Blood samples were provided every 15 min before, during, and 90 min after exercise. Expired gases were collected every 30 min during exercise. In a crossover, randomized, and double-blind fashion, identical testing was completed 1 wk later. Results: Primary findings from this study were that 1) increases in serum glucose were greater during MAL (peak 9.5 mM) versus HMS (peak 7.4 mM, P � 0.01), 2) insulin levels were significantly lower during HMS (peak 2.5 mIU/mL) versus MAL (peak 20.3 mIU/mL, P < 0.001), and 3) HMS was associated with greater fat breakdown as indicated by the increased serum non-esterified fatty acids (P < 0.01) and glycerol levels (P < 0.05). Conclusion: Ingestion of a low-glycemic HMS before prolonged cycling exercise blunted the initial spike in serum glucose and insulin and increased the breakdown in fat compared with MAL.

Creatine supplementation has been found to significantly increase muscle strength and hypertrophy in young adults (≤ 35 yr) particularly when consumed in conjunction with a resistance training regime. Literature examining the efficacy of creatine supplementation in older adults (55-82 yr) suggests creatine to promote muscle strength and hypertrophy to a greater extent than resistance training alone. The following is a review of literature reporting on the effects of creatine supplementation on intramuscular high energy phosphates, skeletal muscle morphology and quality of life in older adults. Results suggest creatine supplementation to be a safe, inexpensive and effective nutritional intervention, particularly when consumed in conjunction with a resistance training regime, for slowing the rate of muscle wasting that is associated with aging. Physicians should strongly consider advising older adults to supplement with creatine and to begin a resistance training regime in an effort to enhance skeletal muscle strength and hypertrophy, resulting in enhanced quality of life.

Shape plays an important role in determining the biomechanical response of a structure. Specimen-specific finite element (FE) models have been developed to capture the details of the shape of biological structures and predict their biomechanics. Shape, however, can vary considerably across individuals or change due to aging or disease, and analysis of the sensitivity of specimen-specific models to these variations has proven challenging. An alternative to specimen-specific representation has been to develop generic models with simplified geometries whose shape is relatively easy to parameterize, and can therefore be readily used in sensitivity studies. Despite many successful applications, generic models are limited in that they cannot make predictions for individual specimens. We propose that it is possible to harness the detail available in specimen-specific models while leveraging the power of the parameterization techniques common in generic models. In this work we show that this can be accomplished by using morphing techniques to parameterize the geometry of specimen-specific FE models such that the model shape can be varied in a controlled and systematic way suitable for sensitivity analysis. We demonstrate three morphing techniques by using them on a model of the load-bearing tissues of the posterior pole of the eye. We show that using relatively straightforward procedures these morphing techniques can be combined, which allows the study of factor interactions. Finally, we illustrate that the techniques can be used in other systems by applying them to morph a femur. Morphing techniques provide an exciting new possibility for the analysis of the biomechanical role of shape, independently or in interaction with loading and material properties.

In this paper, we describe a new method for constructing macro-scale models of the posterior pole of the eye to investigate the role of intraocular pressure in the development and progression of glaucoma. We also describe a method and present results from micro-scale finite element models of the lamina cribrosa microarchitecture that are derived from parent macro-scale continuum models using a novel multiscale substructuring approach. The laminar micro-scale models capture the biomechanical behavior of the laminar trabeculae in a way that cannot be estimated using macro-scale techniques, and predict much higher stresses and strains than those calculated within macro-scale models of the coincident region in the same eye.

Glaucoma is a progressive degenerative optic neuropathy that is projected to affect nearly 60 million people worldwide by 2010.1 Although there are numerous factors involved in the pathogenesis of the disease, including vascular dysfunction and ischemia2,3 and interactions between retinal ganglion cells and the lateral geniculate nucleus and visual cortex,4 intraocular pressure (IOP) clearly plays an important role at all levels of IOP. IOP reduction remains the only clinically proven approach to slowing or halting disease progression.5–8 From a mechanical perspective, IOP exerts a uniform load on the inner eye wall that gives rise to deformations, stresses, and strains within the constituent tissues of the eye. In the posterior pole, the connective tissues of the sclera and lamina cribrosa (LC) play the most important role in bearing IOP-related loads. The connective tissue structures comprising the LC are of particular interest because they span a discontinuity in the scleral shell at the scleral canal and, as such, are located within a region of a substantial IOP-related stress concentration.9,10 There is ample evidence that the LC is the initial site of insult in glaucoma and its complex connective tissue microarchitecture has been correlated with patterns of vision loss and hypothesized to play a key role in axonal damage.11 Thus, it has been suggested that the biomechanical environment of the LC and peripapillary sclera plays an important role in the development and progression of glaucoma, either due to direct mechanical effects or via mechanically mediated effects on blood flow, axoplasmic transport, or cellular activation.10,12 Although a large body of literature has emerged regarding measurement of the compliance behavior of the surface of the optic nerve head (ONH) during elevated IOP,13–19 surface position has been shown to be a poor indicator of underlying laminar and peripapillary scleral position (Agoumi Y, et al. IOVS 2009;50:ARVO E-Abstract 4898).19–21 Several researchers have therefore turned to computational models as a method of describing the biomechanics of these connective tissues. Such computational models of the ONH and peripapillary sclera provide predictions of IOP-related deformation, as well as IOP-related stress and strain that are not obtainable by imaging alone. Bellezza et al.9 used an idealized model of the posterior pole with a rudimentary LC structure to show that the stresses in the ONH could be substantial, even at normal levels of IOP. Sigal et al. have presented both generic parameterized19,22 and eye-specific20,23–25 finite element (FE) models incorporating pre- and retrolaminar neural tissues with scleral, laminar, and pial connective tissues. These parametric studies highlighted the importance of scleral and laminar material properties and scleral thickness on the mechanical environment of the ONH, but suggested that specific details of the ONH geometry had a smaller effect on stresses and strains than expected. Furthermore, Sigal's work demonstrated that IOP-related displacements of the ONH surface may not mirror the underlying laminar displacements and that attempts to infer LC deformation from prelaminar neural tissue measurements can be suspect. More recent work has shown that the interactions between geometric and material factors can be just as important as the impact of each factor individually, suggesting that susceptibility to IOP-related damage may depend on the combinations of anatomic and material characteristics that a given eye possesses.26 None of these previous modeling studies, however, have accounted for the regional variation in LC microarchitecture, but instead have treated the LC as a homogeneous, isotropic material. In a previous report, we described a method of characterizing the inhomogeneous connective tissue microarchitecture in the LC of the monkey eye.27 It is likely that the individual-specific microarchitecture of the LC connective tissue (its spatial distribution and orientation) affect the manner in which load is borne throughout the ONH and hence determine its IOP-related deformation. Separate from its microarchitecture, the material properties of the laminar tissues should also play an important role in the mechanical behavior of the LC. In this study, we incorporated eye-specific LC microarchitectural information into continuum FE models of the LC of paired eyes from four bilaterally normal monkeys that had been perfusion fixed with both eyes at an IOP of 10 mm Hg. We then varied the material properties assigned to this laminar microarchitecture and measured the effect on predicted laminar displacement, neural canal expansion, and laminar strain and stress resulting from a simulated acute IOP elevation from 10 to 45 mm Hg. Our study was designed to address three questions. First, if all other variables are kept constant, to what degree do laminar material properties effect laminar deformation, laminar strain, and laminar stress? Second, to what degree does the biological variation between the two eyes of a normal animal affect these phenomena? Third, are there underlying relationships between laminar microarchitecture and regions of maximum laminar strain and stress that could serve as imaging targets for clinical assessment of glaucomatous susceptibility in the future?

Purpose To characterize optic nerve head (ONH) connective tissue deformation after acute (15 or 30 minutes) intraocular pressure (IOP) elevation in six adult normal monkeys using three-dimensional (3-D) histomorphometry. Methods Trephined ONH and peripapillary sclera from both eyes of six monkeys, each perfusion fixed with one eye at IOP 10 mm Hg (IOP-10) and the other at IOP 30 or 45 mm Hg (IOP-30 or IOP-45, by anterior chamber manometer), were serially sectioned, 3-D reconstructed, 3-D delineated, and quantified according to standard parameters. For each monkey, intereye differences (high-IOP eye minus IOP-10) for each parameter were calculated and compared by ANOVA and EPIDmax both overall and regionally. EPIDmax deformations for each parameter were defined to be those statistically significant differences that exceeded the maximum physiologic intereye difference within six bilaterally normal monkeys in a previous report. Results Regional EPIDmax laminar thinning, posterior bowing of the peripapillary sclera, and thinning and expansion of the scleral canal were present in most high-IOP eyes and were colocalized in those demonstrating the most deformation. Laminar deformation was minimal, not only posteriorly but in some cases anteriorly in the high-IOP eyes. No increase in deformation was seen in the IOP-45 versus the IOP-30 eyes. Conclusions ONH connective tissue alterations after acute IOP elevation involve regional thinning, stretching, and deformation of the lamina cribrosa and peripapillary sclera that are minimal to modest in magnitude. The time-dependent character of these alterations and their compressive, expansile, and shear effects on the axons, the astrocytes, and the laminar and posterior ciliary circulations remain to be determined.

Glaucoma is a chronic and progressive optic neuropathy that gradually narrows the field of vision and can culminate in blindness. Despite extensive and prolonged research efforts, the mechanisms that initiate and fuel progression of the disease are not well understood. However, reduction of intraocular pressure (IOP) has been shown to be an effective therapy for slowing glaucomatous progression, although the specific role of IOP in the disease is not well understood.Copyright © 2009 by ASME

This cross-sectional study examined aging and resistance exercise-related changes in intramuscular gene expression in younger (21.3 +/- 0.6 years, 84.8 +/- 6.0 kg, 26.6 +/- 2.1 kg x m(-2); n = 11) and older men (67.6 +/- 1.3 years, 88.7 +/- 4.8 kg, 28.6 +/- 1.4 kg x m(-2); n = 13) surrounding a single bout of resistance exercise. Participants completed 3 x 10 repetitions at 80% of their 1 repetition maximum for Smith squat, leg press, and leg extension. Muscle biopsies were obtained before and 24 hours after exercise, whereas venous blood was collected before, immediately after and 24 hours after exercise. Free testosterone levels were greater in younger participants at all time points (p0.05), in addition to a greater increase in the younger men immediately post exercise (p0.01). Preexercise human growth hormone levels between age groups were similar (p0.05). Human growth hormone increased immediately post exercise in both groups (p0.05) with a greater response occurring in the younger (p0.001) men. Older men expressed greater levels of androgen receptor (AR) at rest (p = 0.02). A significant correlation existed between preexercise free testosterone levels basal AR gene expression (r = -0.59, p0.01). These data suggest that AR expression patterns may be related to circulating free testosterone levels. Although these findings do not fully unveil the genomic effects of androgen signaling and its relationship to muscle wasting conditions, these results provide a platform for future researchers seeking to employ gene therapy to remedy muscle loss.

Glaucoma is one of the leading causes of blindness worldwide. The loss of vision associated with glaucoma is due to damage to the retinal ganglion cell axons, which transmit visual information to the brain. Damage to these axons is believed to occur as the axons pass through the lamina cribrosa (LC), a connective tissue structure in the optic nerve head at the back of the eye. Elevated intraocular pressure (IOP) has been identified as the main risk factor for the development of the neuropathy, but the mechanism(s) by which a mechanical insult (elevated IOP) is translated into a biological effect (glaucomatous optic neuropathy) is not well understood.

Glaucoma is the second leading cause of irreversible blindness in the world. The biological mechanisms of this disease are not well understood, and the factors contributing to its progression are not well characterized. It is generally accepted that the retinal ganglion cell axons are damaged in glaucoma as they pass through the optic nerve head (ONH). The ONH contains the lamina cribrosa (LC), a fenestrated connective tissue network that spans the scleral canal, through which the axons pass as they leave the eye. It has been postulated that intraocular pressure (IOP)-related stress and strain plays a central role in the pathophysiology of glaucoma [1], so the study of LC biomechanics is important in developing an understanding of the disease.

Objective To determine the safety and efficacy of altering the ratio of carbohydrate and protein in low-energy diets in conjunction with a popular exercise program in obese women. Design Matched, prospective clinical intervention study to assess efficacy of varying ratios of carbohydrate and protein intake in conjunction with a regular exercise program. Participants One-hundred sixty one sedentary, obese, pre-menopausal women (38.5 ± 8.5 yrs, 164.2 ± 6.7 cm, 94.2 ± 18.8 kg, 34.9 ± 6.4 kg·m-2, 43.8 ± 4.2%) participated in this study. Participants were weight stable and not participating in additional weight loss programs. Methods Participants were assigned to either a no exercise + no diet control (CON), a no diet + exercise group (ND), or one of four diet + exercise groups (presented as kcals; % carbohydrate: protein: fat): 1) a high energy, high carbohydrate, low protein diet (HED) [2,600; 55:15:30%], 2) a very low carbohydrate, high protein diet (VLCHP) [1,200 kcals; 63:7:30%], 3) a low carbohydrate, moderate protein diet (LCMP) [1,200 kcals; 50:20:30%] and 4) a high carbohydrate, low protein diet (HCLP) [1,200 kcals; 55:15:30%]. Participants in exercise groups (all but CON) performed a pneumatic resistance-based, circuit training program under supervision three times per week. Measurements Anthropometric, body composition, resting energy expenditure (REE), fasting blood samples and muscular fitness assessments were examined at baseline and weeks 2, 10 and 14. Results All groups except CON experienced significant reductions (P < 0.05 – 0.001) in waist circumference over 14 weeks. VLCHP, LCHP and LPHC participants experienced similar but significant (P < 0.05 – 0.001) reductions in body mass when compared to other groups. Delta responses indicated that fat loss after 14 weeks was significantly greatest in VLCHP (95% CI: -5.2, -3.2 kg), LCMP (-4.0, -1.9 kg) and HCLP (-3.8, -2.1 kg) when compared to other groups. Subsequent reductions in % body fat were significantly greater in VLCHP, LCMP and HCLP participants. Initial dieting decreased (P < 0.05) relative REE similarly in all groups. All exercise groups significantly (P < 0.05) improved in muscular fitness, but these improvements were not different among groups. Favorable but non-significant mean changes occurred in lipid panels, glucose and HOMA-IR. Leptin levels decreased (P < 0.05) in all groups, except for CON, after two weeks of dieting and remained lower throughout the 14 week program. Exercise participation resulted in significant improvements in quality of life and body image. Conclusion Exercise alone (ND) appears to have minimal impact on measured outcomes with positive outcomes apparent when exercise is combined with a hypoenergetic diet. Greater improvements in waist circumference and body composition occurred when carbohydrate is replaced in the diet with protein. Weight loss in all diet groups (VLCHP, LCMP and HCLP) was primarily fat and stimulated improvements in markers of cardiovascular disease risk, body composition, energy expenditure and psychosocial parameters.

An 8-week, split-body, linear periodized resistance training program was completed by college-aged (CA: 18-22 years; n = 24) and middle-aged (MA: 35-50 years; n = 25) men to determine early-phase adaptations in body composition and upper- and lower-body strength. Participants completed 2 upper-body and 2 lower-body resistance training workouts each week. During weeks 1-4, subjects completed 3-6 sets at a 10-repetition maximum (RM) intensity and increased to 8RM for weeks 5-8. The 1RM strength levels were determined on the bench press and leg press, and 30-second Wingate tests were assessed at baseline and after 8 weeks of resistance training. Body composition was assessed using dual-energy X-ray absorptiometry (DXA). For selected data, delta values (post - pre values) were calculated and reported as mean +/- SEM. No changes (p > 0.05) were reported for peak and average Wingate power. Bench press (CA, 3.2 +/- 1.9 kg; MA, 6.2 +/- 3.3 kg; p < 0.001) and leg press (CA, 25.0 +/- 4.4 kg; MA, 18.2 +/- 13.3 kg; p < 0.001) 1RM significantly increased in both groups over time. Lean mass significantly increased over time in both groups (CA, 0.9 +/- 2.4 kg; MA, 1.1 +/- 1.9 kg; p < 0.001). Significant group x time effects were seen for fat mass changes (CA, 0.5 +/- 1.3 kg; MA, -0.5 +/- 1.1 kg; p = 0.01) and % body fat changes (CA, 0.4 +/- 1.4%; MA, -0.7 +/- 1.1%; p = 0.01). These results indicate that performing a split-body, linearly periodized resistance training program for 8 weeks significantly increases bench press 1RM, leg press 1RM, and DXA lean mass in CA and MA men. Furthermore, MA men lost significantly more fat mass and significantly decreased % body fat compared with CA men. A split-body, linearly periodized resistance training program may be used as an effective program to increase strength and lean mass in both young and MA populations.

Bioimpedance spectroscopy (BIS) for the estimation of total body water (TBW) has advantages over isotope dilution techniques, including cost, portability, and ease of use. The aim of the current study was to determine the validity of a BIS device (Imp SFB7) for tracking changes in overfat and obese individuals.Sixty overfat and obese men and women (27+/-8 yr, 33.41+/-3.81%fat) participated in the study. TBW was estimated using BIS and deuterium oxide (D(2)O) before and after the ten-week intervention.Pre-and post-intervention BIS TBW estimations errors increased as body mass index (BMI), fat mass (FM), and fat-free mass (FFM) increased (p0.05). Delta values were more accurate than pre- and post-TBW estimations (total error=1.45 L). Age significantly influenced pre- and post-TBW errors (p0.05). Therefore, a regression equation was developed to correct for the pre- and post-BIS-estimated TBW errors: D(2)O TBW=11.478+0.743(BIS TBW)-2.429(Gender), (Men=1, Women=2).BIS can be considered an accurate tool for tracking changes in TBW regardless of variations in BMI, FM, FFM, or age in both overfat and obese men and women (BMI24). Employing a BIS TBW equation is suggested over the development of resistivity coefficients based on BMI, FM, FFM or age.

Background We have recently demonstrated that consuming a thermogenic drink (TD) acutely increases energy expenditure and serum markers of lipolysis in healthy, college-aged individuals. The purpose of this study was to determine if consuming TD over 28 days affects its acute thermogenic and lipolytic effects as well as body composition and clinical chemistry safety markers. Methods Sixty healthy, males (mean ± SE; 23 ± 1 years, 177 ± 2 cm, 81.7 ± 2.1 kg, 22.8 ± 1.4% body fat; n = 30) and females (23 ± 1 years, 166 ± 2 cm, 62.1 ± 1.8 kg, 28.3 ± 1.4% body fat; n = 30) reported to the laboratory on day 0 (T1) for determination of body composition, resting energy expenditure (REE) as well as glycerol and free fatty acid (FFA) levels before and after ingesting either 336 ml of TD or a non-caloric, non-caffeinated placebo (PLA) drink. Following day 0, participants supplemented daily with 336 ml·day-1 of either TD or PLA and repeated identical testing procedures on day 28 (T2). Day 28 area under the curve (AUC) values were calculated for REE, FFA, and glycerol. Day 28 acute data and prolonged AUC comparisons between groups were analyzed using ANOVAs with repeated measures. Results Percent body fat (p = 0.02) and fat mass (p = 0.01) decreased in the TD group compared to the PLA group after 28 days. Day 28 FFA AUC values (p = 0.048) were greater in the TD group compared to the PLA group. There was no significant difference in day 28 REE AUC values (p = 0.30) or glycerol AUC values (p = 0.21), although a significant increase in REE values in the PLA group may have confounded these findings. There were no differences between groups concerning blood and clinical safety markers. Conclusion Within-group elevations in FFA and REE values in the TD group were still evident following a 28-day supplementation period which may contribute to the observed decrements in %BF. Further, prolonged TD supplementation did not alter the assessed clinical safety markers. Future studies should examine the synergistic and independent effects of the active ingredients in addition to effects of longer ingestion periods of TD ingestion with or without exercise at promoting and sustaining changes in body composition.

Biomechanical response is often influenced by the geometry (shape) of a system. Numerical techniques such as the finite element (FE) method offer the possibility of incorporating geometric details of a system into a mathematical model with a greater level of detail than is generally achievable with purely analytical models. In this vein, FE models of biological structures tend to fall into two broad categories: generic models and specimen-specific models. Generic models are attractive because the geometric features of interest may be cast as variable parameters that simplify analysis of factor influence, but may be limited in what can be predicted about a specific specimen. In contrast, specimen-specific models may contain a high level of geometric detail, but analysis of the influence of geometry can be more complicated.Copyright © 2008 by ASME

Creatine is one of the most popular athletic supplements with sales surpassing 400 million dollars in 2004. Due to the popularity and efficacy of creatine supplementation over 200 studies have examined the effects of creatine on athletic performance. Despite the abundance of research suggesting the effectiveness and safety of creatine, a fallacy appears to exist among the general public, driven by media claims and anecdotal reports, that creatine supplementation can result in muscle cramps and dehydration. Although a number of published studies have refuted these claims, a recent position statement by the American College of Sports Medicine (ACSM) in 2000 advised individuals who are managing their weight and exercising intensely or in hot environments to avoid creatine supplementation. Recent reports now suggest that creatine may enhance performance in hot and/or humid conditions by maintaining haematocrit, aiding thermoregulation and reducing exercising heart rate and sweat rate. Creatine may also positively influence plasma volume during the onset of dehydration. Considering these new published findings, little evidence exists that creatine supplementation in the heat presents additional risk, and this should be taken into consideration as position statements and other related documents are published.

Background To determine the acute effects of ingesting a thermogenic drink (Celsius, Delray Beach, FL) (TD) on changes in metabolism and lipolysis. Methods Healthy college-aged male (23.2 ± 4.0 y, 177.2 ± 6.1 cm, 81.7 ± 11.3 kg, 22.8 ± 7.3 % fat; n = 30) and female (23.4 ± 3.1 y, 165.6 ± 8.7 cm, 62.1 ± 9.9 kg, 28.3 ± 7.4 % fat; n = 30) participants were matched according to height and weight to consume 336 ml of the TD or a non-caloric, non-caffeinated placebo (PLA). After a 12 h fast, participants reported for pre-consumption measures of height, weight, heart rate, blood pressure, resting energy expenditure (REE), respiratory exchange ratio (RER), glycerol and free-fatty acid (FFA) concentrations. REE and RER were determined at 60, 120, and 180 min post-consumption. Serum glycerol and FFA concentrations were determined at 30, 60, 120 and 180 min post-consumption. Results When compared to PLA, TD significantly increased REE at 60, 120 and 180 min (p < 0.05). FFA concentrations were significantly greater in TD compared to PLA at 30, 60, 120 and 180 min post-consumption (p < 0.05). No between-group differences were found in RER. Conclusion Acute TD ingestion significantly increased REE, FFA and glycerol appearance. If sustained, these changes may help to promote weight loss and improve body composition; however, these findings are currently unknown as are the general safety and efficacy of prolonged consumption.

Glaucoma is the second leading cause of blindness in the US and is usually associated with elevated intraocular pressure (IOP). Glaucomatous damage is believed to occur at the optic nerve head (ONH) where the retinal ganglion cell axons pass through an opening in the back of the eye wall on their path to the brain. This opening is spanned by the lamina cribrosa, a fenestrated connective tissue structure that provides structural and nutritional support for the axons as they pass through the eye wall.Copyright © 2007 by ASME

Glaucoma is a chronic disease of the eye that can progress to severe vision impairment or blindness if left untreated. The principal site of glaucomatous damage is believed to be within the optic nerve head (ONH) where the axons of the retinal ganglion cells pass through an opening in the back of the sclera (the eye wall) on their way to form the orbital optic nerve. This opening is spanned by the lamina cribrosa (LC), a fenestrated connective tissue structure which provides both a load bearing function for the eye as well as support (both structural and metabolic) for axonal bundles as they traverse the porous space of the LC.Copyright © 2007 by ASME

Methods Apparently healthy resistance trained males (n = 30) were randomized to either a BCAA group or the CHO control group. Participants performed preliminary testing (T1) to derive peak quadriceps isometric torque, peak quadriceps isokinetic torque (60o and 120o per second), and a 1RM barbell back squat. The following week, the participants performed 10x5 repetitions at 80% of their 1RM barbell back squat for 3 consecutive days. During this experimental intervention antecubital blood was drawn to assess serum myoglobin concentrations, in addition a visual analog scale was utilized in order to measure subjective perceptions of muscular soreness. 48 hours following the third bout of exercise, participants performed post testing (T2) like T1 testing and donated a final blood draw.

Studies have shown that ecological restoration projects are more likely to gain public support if they simultaneously increase important human services that natural resources provide to people. River restoration projects have the potential to influence many of the societal functions (e.g., flood control, water quality) that rivers provide, yet most projects fail to consider this in a comprehensive manner. Most river restoration projects also fail to take into account opportunities for revitalization of large-scale river processes, focusing instead on opportunities presented at individual parcels. In an effort to avoid these pitfalls while planning restoration of the Sacramento River, we conducted a set of coordinated studies to evaluate societal impacts of alternative restoration actions over a large geographic area. Our studies were designed to identify restoration actions that offer benefits to both society and the ecosystem and to meet the information needs of agency planning teams focusing on the area. We worked with local partners and public stakeholders to design and implement studies that assessed the effects of alternative restoration actions on flooding and erosion patterns, socioeconomics, cultural resources, and public access and recreation. We found that by explicitly and scientifically melding societal and ecosystem perspectives, it was possible to identify restoration actions that simultaneously improve both ecosystem health and the services (e.g., flood protection and recreation) that the Sacramento River and its floodplain provide to people. Further, we found that by directly engaging with local stakeholders to formulate, implement, and interpret the studies, we were able to develop a high level of trust that ultimately translated into widespread support for the project.

Introduction: The lipid messenger phosphatidic acid (PA) plays a critical role in the stimulation of mTOR signaling. However, the mechanism by which PA stimulates mTOR is currently unknown. Therefore, the purpose of this study was to compare the effects of various PA precursors and phospholipids on their ability to stimulate mTOR signaling and its ability to augment resistance training-induced changes in body composition and performance. Methods: In phase one, C2C12 myoblasts cells were stimulated with different phospholipids and phospholipid precursors derived from soy and egg sources. The ratio of phosphorylated p70 (P-p70-389) to total p70 was then used as readout for mTOR signaling. In phase two, resistance trained subjects (n = 28, 21 ± 3 years, 77 ± 4 kg, 176 ± 9 cm) consumed either 750 mg PA daily or placebo and each took part in an 8 week periodized resistance training program. Results: In phase one, soy-phosphatidylserine, soy-Lyso-PA, egg-PA, and soy-PA stimulated mTOR signaling, and the effects of soy-PA (+636%) were significantly greater than egg-PA (+221%). In phase two, PA significantly increased lean body mass (+2.4 kg), cross sectional area (+1.0 cm), and leg press strength (+51.9 kg) over placebo. Conclusion: PA significantly activates mTOR and significantly improved responses in skeletal muscle hypertrophy, lean body mass, and maximal strength to resistance exercise.

The adaptation of bone to its mechanical demands is often described as a feedback control system wherein some aspect of the tissue strain environment acts as a driving signal to initiate cellular-level formation and resorption processes on bone surfaces. While this description may be somewhat simplified, the control system view is useful for organizing ideas, experiments, and simulations of adaptation. In the past 25 years, several investigators have introduced mathematical models and (finite element-based) computer simulations of bone adaptation, using numerous candidate driving mechanical signals as proposed bone mass regulators [1]. These simulations generally use the finite element method — including the appropriate geometry, material description, and loading — to calculate the needed tissue strain parameter being considered as the specific regulation signal. Based on the adaptive response being simulated — geometric and/or material property changes — the finite element model is updated, and re-analyzed in a series of discrete time steps.

The purpose of this study was: aim 1) compare insulin and leucine serum responses after feeding a novel hydrolyzed whey protein (WPH)-based supplement versus a whey protein isolate (WPI) in rats during the post-absorptive state, and aim 2) to perform a thorough toxicological analysis on rats that consume different doses of the novel WPH-based supplement over a 30-day period. In male Wistar rats (~250 g, n = 40), serum insulin and leucine concentrations were quantified up to 120 min after one human equivalent dose of a WPI or the WPH-based supplement. In a second cohort of rats (~250 g, n = 20), we examined serum/blood and liver/kidney histopathological markers after 30 days of feeding low (1human equivalent dose), medium (3 doses) and high (6 doses) amounts of the WPH-based supplement. In aim 1, higher leucine levels existed at 15 min after WPH vs. WPI ingestion (p = 0.04) followed by higher insulin concentrations at 60 min (p = 0.002). In aim 2, liver and kidney histopathology/toxicology markers were not different 30 days after feeding with low, medium, high dose WPH-based supplementation or water only. There were no between-condition differences in body fat or lean mass or circulating clinical chemistry markers following the 30-day feeding intervention in aim 2. In comparison to WPI, acute ingestion of a novel WPH-based supplement resulted in a higher transient leucine response with a sequential increase in insulin. Furthermore, chronic ingestion of the tested whey protein hydrolysate supplement appears safe.

Lowering intraocular pressure (IOP) remains the only proven method of preventing or delaying the onset and progression of glaucomatous vision loss, yet the role of IOP in the neuropathy remains unclear.1–3 Several studies have explored the hypothesis that an altered biomechanical environment within the optic nerve head (ONH), and the lamina cribrosa (LC) in particular, may contribute to disruption of the retinal ganglion cell axons and the subsequent loss of vision associated with glaucoma.1,4–15 Hence, there has been a search for an association between changes in IOP and deformations of the LC.5,8–13,16 For some time the conventional paradigm was that, as IOP increases, the LC deforms posteriorly, with the sclera remaining essentially undeformed.16,17 Results from initial studies using radiographic10,11 or histologic8,9 techniques, or measurements of the optic disc surface15,18–20 were interpreted as supportive of this paradigm. More recent numerical6,7,12,13,21–23 and experimental24,25 studies, however, suggest that the relationship between IOP and the deformations of the LC and sclera are more complex than initially thought. It is now clear, for example, that as IOP varies, the sclera deforms, sometimes substantially, and that these deformations, when transmitted to the ONH, may play an important role in the response of the LC to IOP.5,24–26 Numerical models have also predicted that IOP-related anterior–posterior displacements of the LC may be small and could be even smaller in magnitude than lateral LC displacements (i.e., in the plane of the sclera).6,12,22,26,27 This is consistent with recent measurements obtained using 3D histomorphometry and optical coherence tomography (Burgoyne CF, et al. IOVS 2008;49:ARVO E-Abstract 3655; Agoumi Y, et al. IOVS 2009;50:ARVO E-Abstract 4898).25,28 It is now generally accepted that the LC does not respond to IOP changes in isolation, but rather that the ONH and peripapillary sclera behave as a mechanical system, and that the IOP-related deformations of the lamina and sclera are linked. Still, it is not clear how the LC and sclera deform as IOP changes, or how these deformations depend on the tissues' geometry and material properties. Numerical studies suggest that proper characterization of ONH biomechanics requires considering factor interactions (i.e., that the influence of one factor depends on the level of another). Although this seems reasonable, to the best of our knowledge, the role of factor interactions on LC and sclera deformations has not been reported. The broad objective of this work was to study IOP-related anterior–posterior LC displacement (LCD) and scleral canal expansion (SCE). Specifically, we used newly developed parameterized eye-specific finite element models of normal monkey eyes to determine how LCD and SCE depend on the geometry and mechanical properties of the lamina and sclera. We identify the most influential factors, or parameters, and the interactions between them. This work also complements previous numerical and experimental studies by extending to the analysis of IOP-induced LCD and SCE the bioengineering and statistical techniques that we have applied to stresses and strains.5,21

Johnson ML, Roberts MD, Ross AR, Witten CM: Methylphenidate in stroke patients with depression. Am J Phys Med Rehabil 1992;71:239-241. The treatment of depression after stroke is a difficult clinical problem. Many of the medications used to treat patients with depression in the general population have significant potential side effects that are of particular concern in elderly patients. We reviewed the records of ten patients with stroke treated with methylphenidate for depression during an inpatient rehabilitation program. Improvement was noted in seven patients. This suggests that methylphenidate in the treatment of post-stroke depression merits further study.