Familiarization with ambulatory sleep and blood pressure monitoring is necessary for representative data collection.

Ambulatory sleep and blood pressure monitoring are gaining popularity as these can be completed in an individual's home. Little is known regarding the reliability of data and the time it takes to acclimate to the equipment. This study aimed to determine how many nights of wearing the monitoring equipment were required to restore sleep architecture and blood pressure data to baseline. It was hypothesized familiarization would be demonstrated by night 3. Ten male and 10 female subjects completed three nights of sleep and blood pressure recordings. At visit 1, the subjects were familiarized with the equipment and instructed to wear the Sleep Profiler{trade mark, serif} and SunTech Medical Oscar2 ambulatory blood pressure cuff simultaneously for three consecutive nights, then subjects returned the equipment. The percent of time spent in rapid eye-movement (REM) sleep was statistically different on night 3 when compared to night 1. Wake-after-sleep onset and sleep latency were not statistically different between nights 1, 2, and 3. Systolic, diastolic, and pulse pressure were all significantly lower on night 3 compared to night 1. Cortical and autonomic arousals were statistically different on night 3. Ambulatory sleep and blood pressure monitoring need at least 3 nights for familiarization. The percent of time spent in REM sleep was statistically different on night 3 when compared to night 1. Systolic blood pressure, diastolic blood pressure, and pulse pressure were all significantly lower on night 3 compared to night 1. Cortical and autonomic arousals were statistically different on nights 3 and 2, respectively compared to night 1. Based on these findings, ambulatory sleep and blood pressure monitoring takes three nights before the data are reliable and the person is familiarized with the mode of measurement. Therefore, it is recommended to use at least three nights of data collection when using the Sleep Profiler and Oscar2 ambulatory blood pressure cuff in order for results to be valid and reliable.

Central arterial stiffness, wave reflection, and heart rate variability following 4-week high-intensity resistance training intervention in young active women.

PURPOSE: Arterial stiffness, expedited wave reflection, and autonomic dysfunction are risk factors for cardiovascular disease, which is the leading cause of death in women in the United States. Evaluation of the effects of resistance training on these factors has been inconclusive, and even less is known about the effects of high-intensity resistance training (HIRT). This study evaluated the effects of a 4-week HIRT intervention on central arterial stiffness, wave reflection, and heart rate variability in young healthy and active women. METHODS: 9 women were recruited and underwent a 4-week control period followed by the intervention. Measurements were recorded pre-control, post-control/pre-intervention, and post-intervention. RESULTS: There were no significant changes to central arterial stiffness, wave reflection, or heart rate variability. There was a significant increase in resting heart rate (bpm: 62 ± 7, 66 ± 10; p = 0.003) and a significant decrease in baroreceptor sensitivity (30 ± 7, 21 ± 7; p = 0.018) pre- to post-intervention. There was a significant decrease in total peripheral resistance pre- to post-intervention (1.076 ± 0.281, 0.916 ± 0.250; p = 0.002). Squat, bench press, and deadlift increased pre- to post-intervention (kg: 62 ± 11, 71 ± 9, p = 0.000; 37 ± 7, 40 ± 7, p = 0.002; 76 ± 19, 84 ± 19, p = 0.000). CONCLUSION: 4 weeks of HIRT can supplement a healthy lifestyle in women by increasing strength while decreasing peripheral resistance and preserving arterial pressures. Further evaluation is necessary to investigate the observed increase in resting heart rate and decrease in baroreceptor sensitivity and to determine long-term effects of this training.

The effect of acute alcohol ingestion on systemic hemodynamics and sleep architecture in young, healthy men.

Objective Heightened nocturnal blood pressure (BP) may be attributed to the disruption of sleep, a condition worsened by alcohol ingestion. This study investigated the effects of acute alcohol ingestion on hemodynamics and sleep architecture in a young, healthy cohort of male. METHODS: Subjects (n = 17) underwent acute alcohol ingestion reaching a breath alcohol content of 0.08. Each subject endured a battery of hemodynamic tests and had their sleep architecture and nocturnal blood pressure monitored pre- and post-ingestion. Results: Systolic blood pressure (SBP) increased both 30 minutes and 12 hours after alcohol. Ambulatory nocturnal SBP significantly increased after alcohol compared to baseline measures. Minutes of total, rapid eye movement, and light sleep all increased after alcohol ingestion, while a decrease was observed for sleep latency. Conclusions: An acute bout of heavy alcohol consumption may attenuate nocturnal BP dipping that, in turn, may hasten the progression of hypertension-related cardiovascular disease.

Correlation Between Heart Rate at Maximal Fat Oxidation and Aerobic Threshold in Healthy Adolescent Boys and Girls.

PURPOSE: To investigate the association between the heart rate (HR) at maximal fat oxidation (MFO) and the HR at the aerobic threshold (AerT) in adolescent boys and girls, and to identify sex differences in the intensity that elicits MFO (Fatmax) as a percentage of HR peak (HRpeak). METHODS: Fifty-eight healthy adolescents participated in this study (29 boys and 29 girls). Participants performed a cardiopulmonary exercise test on a cycle ergometer. MFO was calculated using a stoichiometric equation, and the AerT was identified using gas exchange parameters. RESULTS: A strong correlation between HR at Fatmax and HR at AerT was found in both boys and girls (r = .96 and .94, respectively). Fatmax as a percentage of HRpeak occurred at 61.0% (4.9%) of HRpeak and 66.8% (6.9%) of HRpeak in adolescent boys and girls (P = .001, F = 13.6), respectively. MFO was higher in boys compared with girls (324 [150] and 240 [95] mg/min, respectively), and no sex differences were observed in the relative contribution of fat to energy expenditure at Fatmax. CONCLUSIONS: HR at Fatmax and HR at AerT were highly correlated in adolescent boys and girls. Girls obtained Fatmax at a higher percentage of HRpeak than boys.

Measures of ejection duration and subendocardial viability ratio in normal weight and overweight adolescent children.

The aim of our study was to determine how being overweight (OW) affects measures of ejection duration (ED), subendocardial viability ratio (SEVR), and central arterial health in a sample of adolescent children. Thirty-four sex and age-matched adolescent children (n = 34, 17 OW, age = 14 ± 2 years) participated in one laboratory visit. Anthropometric measures, body composition, and cardiovascular measures including resting heart rate, aortic systolic blood pressure (ASBP), carotid-femoral pulse wave velocity (cf-PWV), ED (EDms absolute vs. relative ED%), and the SEVR were ascertained. Transfer functions were applied to obtain ASBP. ED was measured as the time from the beginning of the upstroke of the pulse wave and the dicrotic notch, SEVR as the quotient of the diastolic pressure-time area to the systolic pressure-time area, and cf-PWV as the quotient of distance between carotid-femoral measurement sites and the transit time of the pulse wave. cf-PWV was significantly higher in OW compared to normal weight participants (5.13 ± 0.85 vs. 4.53 ± 0.46 m/s respectively; p = 0.015, d = 0.51). OW adolescents also reported significantly higher values for ASBP (103.1 ± 11.8 vs. 95.7 ± 8.2 mmHg respectively; p = 0.043, d = 0.72) and significantly lower values of SEVR (114.4 ± 25.9% vs. 132.2 ± 22.0% respectively; p = 0.038; d = 0.33). Overweight adolescents demonstrated higher cf-PWV, ASBP, and SEVR then normal weight peers.

Opposite Surfaces of the Cdc15 F-BAR Domain Create a Membrane Platform That Coordinates Cytoskeletal and Signaling Components for Cytokinesis.

Many eukaryotes assemble an actin- and myosin-based cytokinetic ring (CR) on the plasma membrane (PM) for cell division, but how it is anchored there remains unclear. In Schizosaccharomyces pombe, the F-BAR protein Cdc15 links the PM via its F-BAR domain to proteins in the CR's interior via its SH3 domain. However, Cdc15's F-BAR domain also directly binds formin Cdc12, suggesting that Cdc15 may polymerize a protein network directly adjacent to the membrane. Here, we determine that the F-BAR domain binds Cdc12 using residues on the face opposite its membrane-binding surface. These residues also bind paxillin-like Pxl1, promoting its recruitment with calcineurin to the CR. Mutation of these F-BAR domain residues results in a shallower CR, with components localizing ∼35% closer to the PM than in wild type, and aberrant CR constriction. Thus, F-BAR domains serve as oligomeric membrane-bound platforms that can modulate the architecture of an entire actin structure.

Bicelles Rich in both Sphingolipids and Cholesterol and Their Use in Studies of Membrane Proteins.

How the distinctive lipid composition of mammalian plasma membranes impacts membrane protein structure is largely unexplored, partly because of the dearth of isotropic model membrane systems that contain abundant sphingolipids and cholesterol. This gap is addressed by showing that sphingomyelin and cholesterol-rich (SCOR) lipid mixtures with phosphatidylcholine can be cosolubilized by n-dodecyl-ß-melibioside to form bicelles. Small-angle X-ray and neutron scattering, as well as cryo-electron microscopy, demonstrate that these assemblies are stable over a wide range of conditions and exhibit the bilayered-disc morphology of ideal bicelles even at low lipid-to-detergent mole ratios. SCOR bicelles are shown to be compatible with a wide array of experimental techniques, as applied to the transmembrane human amyloid precursor C99 protein in this medium. These studies reveal an equilibrium between low-order oligomer structures that differ significantly from previous experimental structures of C99, providing an example of how ordered membranes alter membrane protein structure.

Comprehensive Clinicopathologic Analyses of Acquired Cystic Disease-associated Renal Cell Carcinoma With Focus on Adverse Prognostic Factors and Metastatic Lesions.

Acquired cystic disease of kidney-associated renal cell carcinoma (ACD-RCC) is a distinct subtype of renal cell carcinoma with unique morphologic and clinicopathologic features. Generally, ACD-RCC is regarded as an indolent tumor; however, prognostic and outcomes data have been conflicted by the limited and relatively low number of cases with patient follow-up or adverse events. In this study, we focused on the histology of metastatic lesions and identifying prognostic factors associated with metastatic progression. From 32 cases in the cohort, 9 patients had metastasis [ACD-RCC (M+)] and 23 patients were without metastasis [ACD-RCC (M-)]. The median age of patients was 52 years; right side, n=10; left side, n=18; bilateral, n=4; median tumor size=2.6 cm; median hemodialysis duration=17 y; and the median duration of follow-up was 50 mo. Immunohistochemistry showed ACD-RCC to be racemase positive and CK7 negative to focally positive within tumor cells, with consistent positivity for renal histogenesis-associated markers (PAX8 and RCC antigen); S100A1 was a less reliable marker at metastatic sites. All metastatic ACD-RCC except 2 cases involved lymph nodes (para-aortic, renal hilar, subclavicular). Overall, 6/9 (67%) had visceral metastasis to sites including lung (n=3), liver (n=3), bone (n=5), stomach (n=1), and brain (n=1). In total, 5/9 (56%) metastatic tumors had distinctive cystic growth pattern at the metastatic site; intriguingly metastatic tumors had intrametastatic oxalate crystal deposition, a pathognomonic feature associated with primary tumors. Four of nine (44%) patients with ACD-RCC (M+) had fatal outcomes due to metastatic disease. Clinically significant adverse prognostic features associated with metastasis [median follow-up 47 mo, ACD-RCC (M+) vs. ACD-RCC (M-), 50 mo] included: duration of hemodialysis (≥20 vs. <20 y, P=0.0085) and tumor necrosis (P=0.049). Because of sufficient overlap between these parameters, the study was not able to identify parameters that would be reliable in further management strategies, in clinical settings. Our data indicate that ACD-RCC is a tumor which has distinct metastatic potential with nodal and visceral tropism and proclivity for cystic morphology at metastatic sites; this is the first report of the presence of oxalate crystals in metastatic tumors. Our data suggest that ACD-RCC patients with prolonged hemodialysis and tumoral coagulative necrosis require additional surveillance in view of the association of these parameters with metastatic progression.

Withings Body Cardio versus Gold Standards of Pulse-Wave Velocity and Body Composition.

Home blood pressure monitors are widely used by consumers yet cardiovascular health may be better defined by pulse-wave velocity (PWV). So far, the Withings Body Cardio scale is the only consumer device that has been designed to measure PWV and body composition, including fat mass (FM) and fat-free mass (FFM), in the home setting. While one study has demonstrated that this device meets the acceptable accuracy standards of the ARTERY Society, no study has accounted for the gravitational effect of standing on a scale on aortic-leg PWV. PURPOSE: The purpose of this study was to assess the accuracy of PWV and body composition as determined by the Body Cardio scale. METHODS: Measurements of PWV and body composition in healthy, young males and females (n = 20) using the Body Cardio device were compared to PWV assessed by applanation tonometry (SphygmoCor) and body composition analysis determined by air displacement plethysmography (Bod Pod). Bland-Altman analysis and mean absolute percent error (MAPE) were used to assess accuracy. RESULTS: Data are reported as the mean bias (95% confidence interval). The Body Cardio overestimated PWV by 0.68 m/s (-0.16, 1.51) and FM by 2.91 kg (-2.91, 8.73). Body Cardio PWV and FM estimations had a MAPE of 9.7% and 25.8%, respectively. The Body Cardio underestimated body mass (BM) and FFM by 0.11 kg (-0.41, 0.18) and 2.87 kg (-9.04, 3.30), respectively. Body Cardio BM and FFM estimations had a MAPE of 0.15% and 5.6%, respectively. CONCLUSIONS: The Body Cardio scale provides accurate measures of BM and PWV; however, it should be used cautiously for measures of FM and FFM.

Effects of Continuous vs Discontinuous Aerobic Training on Cardiac Autonomic Remodeling.

The aim of this study was to examine the cardiac autonomic nervous system differences following either continuous vs. discontinuous exercise in males and females. Forty-seven healthy male and female subjects (M=19, F=28; Age=36.95±13.79) underwent a baseline test for VO2peak and tilt table testing. They were assigned to a one-month control period before returning to repeat the testing and then begin one month of either continuous aerobic treadmill work for 30 min at 70% peak heart rate (N=23) or 3 bouts of 10 min at 70% of peak heart rate with two 10-min break periods in between (N=24). Following exercise, both groups demonstrated a significant improvement in VO2peak (p<0.001). Treatment differences were detected while tilted in continuous as a decreases in the percentage of instances within an hour that the normal sinus interval exceeds 50 ms (p=0.036) and in the high-frequency component (p=0.023). While supine, the discontinuous group saw reduction in heart rate (p=0.004), and an increase in high-frequency (p=0.018). These data suggest that for healthy people either continuous or discontinuous aerobic training is effective in improving measures of fitness; however discontinuous is better able to improve supine indices of vagal activity on heart rate variability.

Differential Effects of Continuous Versus Discontinuous Aerobic Training on Blood Pressure and Hemodynamics.

Landram, MJ, Utter, AC, Baldari, C, Guidetti, L, McAnulty, SR, and Collier, SR. Differential effects of continuous versus discontinuous aerobic training on blood pressure and hemodynamics. J Strength Cond Res 32(1): 97-104, 2018-The purpose of this study was to compare the hemodynamic, arterial stiffness, and blood flow changes after 4 weeks of either continuous or discontinuous aerobic exercise in adults. Forty-seven subjects between the ages of 18 and 57 were recruited for 1 month of either continuous aerobic treadmill work for 30 minutes at 70% max heart rate or 3 bouts of 10 minutes of exercise at 70% of max heart rate with two 10 minutes break periods in between, totaling 30 minutes of aerobic work. After exercise, both continuous (CON) and discontinuous (DIS) groups demonstrated a significant improvement in maximal oxygen uptake (V[Combining Dot Above]O2max, CON 35.39 ± 1.99 to 38.19 ± 2.03; DIS 36.18 ± 1.82 to 39.33 ± 1.75), heart rate maximum (CON 183.5 ± 3.11 to 187.17 ± 3.06; DIS 179.06 ± 2.75 to 182 ± 2.61), decreases in systolic blood pressure (CON 119 ± 1.82 to 115.11 ± 1.50; DIS 117.44 ± 1.90 to 112.67 ± 1.66), diastolic blood pressure (CON 72.56 ± 1.65 to 70.56 ± 1.06; DIS 71.56 ± 1.59 to 69.56 ± 1.43), augmentation index (CON 17.17 ± 2.17 to 14.9 ± 1.92; DIS 19.71 ± 2.66 to 13.91 ± 2.46), central pulse wave velocity (CON 8.29 ± 0.32 to 6.92 ± 0.21; DIS 7.85 ± 0.30 to 6.83 ± 0.29), peripheral pulse wave velocity (CON 9.49 ± 0.35 to 7.72 ± 0.38; DIS 9.11 ± 0.37 to 7.58 ± 0.47), and significant increases in average forearm blood flow (CON 4.06 ± 0.12 to 4.34 ± 0.136; DIS 4.26 ± 0.18 to 4.53 ± 0.15), peak forearm blood flow (FBF) after reactive hyperemia (CON 28.45 ± 0.094 to 29.96 ± 0.45; DIS 29.29 ± 0.46 to 30.6 ± 0.38), area under the curve (AUC) of FBF (CON 28.65 ± 1.77 to 30.4 ± 1.08; DIS 30.52 ± 1.9 to 31.67 ± 1.44), and AUC peak FBF after reactive hyperemia (CON 222.3 ± 5.68 to 231.95 ± 4.42; DIS 230.81 ± 6.91 to 237.19 ± 5.39). These data suggest that for healthy people either 4 weeks of continuous or discontinuous aerobic training is effective in improving measures of fitness and vascular health.

Metabolomic Shifts Following Play-Based Activity in Overweight Preadolescents.

BACKGROUND: Play-based activities can be a positive intervention to increase participation of overweight children. Metabolomics can reveal elemental shifts in the metabolome, lending to potential mechanistic explanations behind improvements in physiological systems. OBJECTIVE: To elucidate dose-response urinary metabolomic signature shifts in overweight preadolescents following four or eight weeks of supervised play-based activity versus a typical summer break control group. We hypothesized that eight weeks of activity would cause the greatest shift in the metabolites. STUDY DESIGN: Twenty-two recreationally active preadolescents (12 males, 10 females) were randomly assigned to a four-week (4w) or eight-week (8w) activity group or to a control group (C). Participants reported to the laboratory on two separate occasions during which descriptive characteristics were recorded and urine samples were obtained. Children in the 4w and 8w cohort were tested at the beginning and end of the four and eight weeks of a supervised play-based physical activity program where they were active for 6 hours a day, 5 days a week. Children in the C group were tested before and after eight weeks of an unsupervised summer break. RESULTS: A valid supervised partial least squares discriminant analysis model was obtained between post-exercise subjects in 8w and C (3 components, R2X = 0.332, R2Y = 0.976, Q2 = 0.091). The eight week intervention yielded significant metabolomic changes in several identified compounds. CONCLUSION: When compared to a typical unsupervised summer break, a supervised play-based intervention provides enough of a stimulus for a shift in the metabolome.

How consumer physical activity monitors could transform human physiology research.

A sedentary lifestyle and lack of physical activity are well-established risk factors for chronic disease and adverse health outcomes. Thus, there is enormous interest in measuring physical activity in biomedical research. Many consumer physical activity monitors, including Basis Health Tracker, BodyMedia Fit, DirectLife, Fitbit Flex, Fitbit One, Fitbit Zip, Garmin Vivofit, Jawbone UP, MisFit Shine, Nike FuelBand, Polar Loop, Withings Pulse O2, and others have accuracies similar to that of research-grade physical activity monitors for measuring steps. This review focuses on the unprecedented opportunities that consumer physical activity monitors offer for human physiology and pathophysiology research because of their ability to measure activity continuously under real-life conditions and because they are already widely used by consumers. We examine current and potential uses of consumer physical activity monitors as a measuring or monitoring device, or as an intervention in strategies to change behavior and predict health outcomes. The accuracy, reliability, reproducibility, and validity of consumer physical activity monitors are reviewed, as are limitations and challenges associated with using these devices in research. Other topics covered include how smartphone apps and platforms, such as the Apple ResearchKit, can be used in conjunction with consumer physical activity monitors for research. Lastly, the future of consumer physical activity monitors and related technology is considered: pattern recognition, integration of sleep monitors, and other biosensors in combination with new forms of information processing.

Extreme Conditioning Program Induced Acute Hypotensive Effects are Independent of the Exercise Session Intensity.

The aim of the study was to determine the acute systolic (SBP) and diastolic (DBP) blood pressure, rating of perceived exertion (RPE) and heart rate (HR) responses following two intense training sessions (24 hours apart). Nine male extreme conditioning program (ECP) practitioners with more than 6 months of experience (age 26.7 ± 6.6 years; body mass 78.8 ± 13.2 kg; body fat 13.5 ± 6.2 %) completed two experimental ECP sessions. Cardiovascular variables were measured before, immediately after and every 15 min during a 45 min recovery following each experimental session. Compared with pre-exercise data, our results showed a SBP decrease at 30 min post exercise session 1 (P≤0.05) and at 45 min following exercise session 2. DBP decreased (P≤0.05) at 15 min and 30 min following exercise session 1 and at 30 min after the exercise session 2, respectively. HR remained significantly higher (P≤0.05) 45 min following the first and second exercise session compared with pre-exercise values. Exercise session 1 induced a higher increase in HR (86 ± 11% of HRmax versus 82 ± 12% of HRmax, p = 0.01) and RPE (8.8 ± 1.2 versus 8.0 ± 1.2, p = 0.02) when compared to exercise session 2. In conclusion, post-exercise hypotension occurs following strenuous exercise sessions, regardless of the session design, which may have an important role in the prevention of cardiovascular diseases.

Effects of tai chi chuan on anxiety and sleep quality in young adults: lessons from a randomized controlled feasibility study.

OBJECTIVE: To determine feasibility and estimate the effect of a 10-week tai chi chuan (TCC) intervention on anxiety and sleep quality in young adults. PARTICIPANTS: Seventy-five adults (18-40 years) from a predominately undergraduate midsized university. METHODS: This was an assessor blinded, randomized feasibility trial, and participants were randomized into one of three groups: 10 weeks of TCC meeting 2 times per week, 10 weeks of TCC with a DVD of the curriculum, and control group receiving a handout on anxiety management. Anxiety and sleep quality were assessed 4 times: baseline, 4 weeks, 10 weeks (immediate post-intervention), and 2 months post-intervention. Retention was defined as a participant attending the baseline assessment and at least one other assessment. Adherence to the intervention was set a priori as attendance at 80% of the TCC classes. RESULTS: Eighty-five percent of participants were retained during the intervention and 70% completed the 2 month follow-up assessments. To increase statistical power, the two TCC groups were combined in the analyses of anxiety and sleep quality measures. No significant changes in anxiety were found in the control group, while levels of anxiety decreased significantly over time in the two TCC groups. Sleep quality scores improved across time for all three groups, but adherent TCC participants reported greater improvement than control participants. CONCLUSION: TCC may be an effective nonpharmaceutical means of improving anxiety and poor sleep quality in young adults.

Tai Chi and Kung-Fu practice maintains physical performance but not vascular health in young versus old participants.

OBJECTIVES: Kung-Fu and Tai Chi along with other martial arts are gaining popularity but studies examining the benefits of martial arts on physical fitness, vascular health, nutrition, and psychological wellness are limited. Aging is associated with declines in these health components. The objectives of this study were to examine whether Tai Chi and Kung-Fu training would maintain physical fitness, vascular health, and psychological wellness components on older versus younger practitioners. METHODS: Seventeen subjects were recruited and divided into Young (age <40 years, n=9) and Old (age 40 years and above, n=8). Participants reported twice for health screens, vascular and nutrition assessment, and fitness tests. Mean differences were compared between groups for all tests using Student's t-tests. RESULTS: Age, months of practice, systolic blood pressure, and cardiovascular augmentation index were significantly greater in Old versus Young (p=0.001, p=0.007, p=0.049, and p=0.011, respectively). Psychologically, old practitioners experienced greater sleep interference (p=0.035) and overall pain (p=0.036). No other differences existed for any variable. CONCLUSION: Our study indicates that the practice of Tai Chi and Kung-Fu maintains physical fitness in older compared to younger practitioners. However, age associated changes in cardiovascular stiffness, systolic blood pressure, and pain were not prevented.

Biased Brownian motion as a mechanism to facilitate nanometer-scale exploration of the microtubule plus end by a kinesin-8.

Kinesin-8s are plus-end-directed motors that negatively regulate microtubule (MT) length. Well-characterized members of this subfamily (Kip3, Kif18A) exhibit two important properties: (i) They are "ultraprocessive," a feature enabled by a second MT-binding site that tethers the motors to a MT track, and (ii) they dissociate infrequently from the plus end. Together, these characteristics combined with their plus-end motility cause Kip3 and Kif18A to enrich preferentially at the plus ends of long MTs, promoting MT catastrophes or pausing. Kif18B, an understudied human kinesin-8, also limits MT growth during mitosis. In contrast to Kif18A and Kip3, localization of Kif18B to plus ends relies on binding to the plus-end tracking protein EB1, making the relationship between its potential plus-end-directed motility and plus-end accumulation unclear. Using single-molecule assays, we show that Kif18B is only modestly processive and that the motor switches frequently between directed and diffusive modes of motility. Diffusion is promoted by the tail domain, which also contains a second MT-binding site that decreases the off rate of the motor from the MT lattice. In cells, Kif18B concentrates at the extreme tip of a subset of MTs, superseding EB1. Our data demonstrate that kinesin-8 motors use diverse design principles to target MT plus ends, which likely target them to the plus ends of distinct MT subpopulations in the mitotic spindle.

Mobile phones in residential treatment: implications for practice.

A nonprofit primary care, substance abuse and mental health treatment provider that operates nine separate residential treatment facilities in both northern and southern California began allowing clients to keep their mobile phones while in treatment. From the advent of mobile phone technology and its widespread adoption through early 2013, the organization prohibited clients from having phones while in treatment. Calls to and from clients needed to be made and received at the house phone. After years of enforcing the policy with diminished success as phones became cheaper, smaller, and more prevalent, agency leadership decided to experiment with allowing the clients to keep their phones while in treatment. Elopement data as they relate to the policy are examined along with data from staff interviews about its implementation and impact. Results show that elopements resulting from being caught with a mobile phone were eliminated and some clients were able to be returned to treatment using the devices. All seven (100%) of the interviewees were supportive of the new policy and thought it should be continued. The impact of the policy on clinical disruptions, lost/stolen property liability, and confidentiality issues are discussed.

Acute Sodium Ingestion Before Exercise Increases Voluntary Water Consumption Resulting In Preexercise Hyperhydration and Improvement in Exercise Performance in the Heat.

Dehydration has been shown to hinder performance of sustained exercise in the heat. Consuming fluids before exercise can result in hyperhydration, delay the onset of dehydration during exercise and improve exercise performance. However, humans normally drink only in response to thirst, which does not result in hyperhydration. Thirst and voluntary fluid consumption have been shown to increase following oral ingestion or infusion of sodium into the bloodstream. We measured the effects of acute sodium ingestion on voluntary water consumption and retention during a 2-hr hydration period before exercise. Subjects then performed a 60-min submaximal dehydration ride (DR) followed immediately by a 200 kJ performance time trial (PTT) in a warm (30 °C) environment. Water consumption and retention during the hydration period was greater following sodium ingestion (1380 ± 580 mL consumed, 821 ± 367 ml retained) compared with placebo (815 ± 483 ml consumed, 244 ± 402 mL retained) and no treatment (782 ± 454 ml consumed, 148 ± 289 mL retained). Dehydration levels following the DR were significantly less after sodium ingestion (0.7 ± 0.6%) compared with placebo (1.3 ± 0.7%) and no treatment (1.6 ± 0.4%). Time to complete the PTT was significantly less following sodium consumption (773 ± 158 s) compared with placebo (851 ± 156 s) and no treatment (872 ± 190 s). These results suggest that voluntary hyperhydration can be induced by acute consumption of sodium and has a favorable effect on hydration status and performance during subsequent exercise in the heat.

Glycolytic enzymes localize to ribonucleoprotein granules in Drosophila germ cells, bind Tudor and protect from transposable elements.

Germ cells give rise to all cell lineages in the next-generation and are responsible for the continuity of life. In a variety of organisms, germ cells and stem cells contain large ribonucleoprotein granules. Although these particles were discovered more than 100 years ago, their assembly and functions are not well understood. Here we report that glycolytic enzymes are components of these granules in Drosophila germ cells and both their mRNAs and the enzymes themselves are enriched in germ cells. We show that these enzymes are specifically required for germ cell development and that they protect their genomes from transposable elements, providing the first link between metabolism and transposon silencing. We further demonstrate that in the granules, glycolytic enzymes associate with the evolutionarily conserved Tudor protein. Our biochemical and single-particle EM structural analyses of purified Tudor show a flexible molecule and suggest a mechanism for the recruitment of glycolytic enzymes to the granules. Our data indicate that germ cells, similarly to stem cells and tumor cells, might prefer to produce energy through the glycolytic pathway, thus linking a particular metabolism to pluripotency.