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Kworweinski Lafontant,1,2 Amber Blount,2,3 Jethro Raphael M Suarez,2,4 David H Fukuda,1 Jeffrey R Stout,1,5 Evette M Trahan,2 Nichole R Lighthall,3 Joon-Hyuk Park,4,5 Rui Xie,2,6 Ladda Thiamwong2,5 1Institute of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, USA; 2College of Nursing, University of Central Florida, Orlando, FL, USA; 3Department of Psychology, University of Central Florida, Orlando, FL, USA; 4Mechanical and Aerospace Engineering Department, University of Central Florida, Orlando, FL, USA; 5Disability, Aging, and Technology Cluster, University of Central Florida, Orlando, FL, USA; 6Department of Statistics and Data Science, University of Central Florida, Orlando, FL, USACorrespondence: Ladda Thiamwong, UCF College of Nursing, 12201 Research Parkway, Suite 300, Orlando, FL, 32826, USA, Tel +1 407 823 5091, Email ladda.thiamwong@ucf.eduPurpose: The US Centers for Disease Control and Prevention (CDC) has implemented the Stopping Elderly Accidents, Deaths, and Injuries (STEADI) initiative. This initiative provides an algorithm for fall risk screening. However, the algorithm has the potential to overcategorize individuals as high risk for falling upon initial screening, which may burden clinicians with the task of recategorizing individuals after follow-up testing. Therefore, this study aimed to compare the accuracy, sensitivity, and specificity of fall risk appraisal between the STEADI, Short Fall-Efficacy Scale International (FES-I), and portable balance system (BTrackS) assessments in community-dwelling older adults.Patients and Methods: This cross-sectional analysis included 122 community-dwelling older adults, comprising 94 women and 28 men. Center-of-pressure postural sway was assessed using the BTrackS, fear of falling was assessed using the Short FES-I questionnaire, and all participants completed the STEADI checklist. Each assessment categorized participants as either high or low fall risk and fall risk appraisal was compared between groups using McNemar tests.Results: The STEADI checklist (high risk: n = 62; low risk: n = 60) significantly differed in fall risk appraisal compared to the BTrackS (high risk: n = 44; low risk: n = 78; p = 0.014) and the Short FES-I (high risk: n = 42; low risk: n = 80; p = 0.002). Compared to the BTrackS, the STEADI checklist had a specificity of 62.8%, sensitivity of 70.5%, and accuracy of 65.6%. Compared to the Short FES-I, the STEADI checklist had a specificity of 67.5%, sensitivity of 81.0%, and accuracy of 72.1%.Conclusion: The STEADI checklist appears to overcategorize individuals as high fall risk more frequently than direct assessments of postural sway and fear of falling. Further research is needed to examine potential improvements in accuracy when combining the STEADI checklist with direct assessments of postural sway and/or fear of falling.Plain Language Summary: Fall risk assessments are crucial for preventative care in older adults. However, the demands of clinical practice require an accurate and time-efficient method. The U.S Centers for Disease Control and Prevention (CDC) has implemented a fall risk checklist through the Stopping Elderly Accidents, Deaths, and Injuries (STEADI) initiative. However, the STEADI checklist might cost clinicians more time than expected, as some patients initially classified as high risk for falling may not actually be at high risk. This leads to unnecessary follow-up assessments. In this study, we compared the STEADI checklist to direct measures of postural sway (balance) using the BTrackS system and fear of falling using the Short FES-I survey to determine how they differed in classifying community-dwelling older adults as high versus low fall risk. Our results show that the STEADI checklist classifies older adults as high risk more frequently than the BTrackS and Short FES-I. Considering that the follow-up assessments for a high-risk classification by the STEADI checklist include a balance test, we suggest that combining a balance test such as the BTrackS with a questionnaire or checklist may yield better screening outcomes and accurately identify high-risk individuals in a timely manner. Further research is needed to determine the effectiveness of this combination and to establish a true gold standard method for fall risk appraisal.Keywords: balance, postural sway, fall efficacy, clinical practice

Introduction: Sacrococcygeal teratomas are typically benign tumors containing endoderm, mesoderm, and ectoderm derived tissues. They are the most common extragonadal fetal tumor and arise from the sacrococcygeal junction. These tumors can have varying levels of intrapelvic involvement, which serves as the basis for their classification system. Case presentation: This case report describes the interesting prenatal and postnatal course of a newborn with a sacrococcygeal teratoma, identified at 24 weeks via ultrasound, which underwent in utero autoamputation. Ultrasound at 34 weeks gestation revealed the teratoma freely floating in the uterine cavity. The patient was delivered via cesarean section at full term, along with the teratoma. Postnatal spinal ultrasound and MRI revealed a remaining intrapelvic portion of the mass which required surgical resection. Approximately 15 months post resection, the patient's surveillance AFP level was elevated. Cross sectional imaging revealed a 5cm solid mass in the presacral space. The patient ultimately received chemotherapy and additional resection for recurrence. Conclusion: Sacrococcygeal teratomas are a common fetal tumor with varying presentations documented in the literature. The most common presentation is a sacral mass, with variations dependent on size, location, and extension of the tumor. Our patient's presentation of a type I tumor undergoing in utero autoamputation is believed to be the first of its kind. Alternatively, our case could possibly be a yet undescribed mechanism for type IV tumors, which have no external component.

ABSTRACT: Osteocyte processes are an order of magnitude more sensitive to mechanical loading than their cell bodies. The mechanisms underlying this remarkable mechanosensitivity are not clear, but may be related to the infrequent αVβ3 integrin sites where the osteocyte cell processes attach to canalicular walls. These sites develop dramatically elevated strains during load‐induced fluid flow in the lacunar‐canalicular system and were recently shown to be primary sites for osteocyte‐like MLO‐Y4 cell mechanotransduction. These αVβ3 integrin sites lack typical integrin transduction mechanisms. Rather, stimulation at these sites alters Ca2+ signaling, ATP release and membrane potential. In the current studies, we tested the hypothesis that in authentic osteocytes in situ, key membrane proteins implicated in osteocyte mechanotransduction are preferentially localized at or near to β3 integrin‐foci. We analyzed these spatial relationships in mouse bone osteocytes using immunohistochemistry combined with Structured Illumination Super Resolution Microscopy, a method that permits structural resolution at near electron microscopy levels in tissue sections. We discovered that the purinergic channel pannexin1, the ATP‐gated purinergic receptor P2 × 7R and the low voltage transiently opened T‐type calcium channel CaV3.2–1 all reside in close proximity to β3 integrin attachment foci on osteocyte processes, suggesting a specialized mechanotransduction complex at these sites. We further confirmed this observation on isolated osteocytes in culture using STochasitc Optical Resonance Microscopy. These findings identify a possible structural basis for the unique mechanosensation and transduction capabilities of the osteocyte process. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:642–652, 2018. [ABSTRACT FROM AUTHOR]

Gap junctions (GJs) are made up of plaques of laterally clustered intercellular channels and the membranes in which the channels are embedded. Arrangement of channels within a plaque determines subcellular distribution of connexin binding partners and sites of intercellular signaling. Here, we report the discovery that some connexin types form plaque structures with strikingly different degrees of fluidity in the arrangement of the GJ channel subcomponents of the GJ plaque. We uncovered this property of GJs by applying fluorescence recovery after photobleaching to GJs formed from connexins fused with fluorescent protein tags. We found that connexin 26 (Cx26) and Cx30 GJs readily diffuse within the plaque structures, whereas Cx43 GJs remain persistently immobile for more than 2 min after bleaching. The cytoplasmic C terminus of Cx43 was required for stability of Cx43 plaque arrangement. We provide evidence that these qualitative differences in GJ arrangement stability reflect endogenous characteristics, with the caveat that the sizes of the GJs examined were necessarily large for these measurements. We also uncovered an unrecognized effect of non-monomerized fluorescent protein on the dynamically arranged GJs and the organization of plaques composed of multiple connexin types. Together, these findings redefine our understanding of the GJ plaque structure and should be considered in future studies using fluorescent protein tags to probe dynamics of highly ordered protein complexes. [ABSTRACT FROM AUTHOR]

Treatment of dentin hypersensitivity with oxalates is common, but oxalate efficacy remains unclear. Our objective was to systematically review clinical trials reporting an oxalate treatment compared with no treatment or placebo with a dentin hypersensitivity outcome. Risk-of-bias assessment and data extraction were performed independently by two reviewers. Standardized mean differences (SMD) were estimated by random-effects meta-analysis. Of 677 unique citations, 12 studies with high risk-of-bias were included. The summary SMD for 3% monohydrogen-monopotassium oxalate (n = 8 studies) was -0.71 [95% Confidence Interval: -1.48, 0.06]. Other treatments, including 30% dipotassium oxalate (n = 1), 30% dipotassium oxalate plus 3% monohydrogen monopotassium oxalate (n = 3), 6% monohydrogen monopotassium oxalate (n = 1), 6.8% ferric oxalate (n = 1), and oxalate-containing resin (n = 1), also were not statistically significantly different from placebo treatments. With the possible exception of 3% monohydrogen monopotassium oxalate, available evidence currently does not support the recommendation of dentin hypersensitivity treatment with oxalates. [ABSTRACT FROM AUTHOR]

The ability to accurately estimate changes in muscle cross-sectional area (CSA) could be a useful tool for strength and conditioning practitioners to assess the effectiveness of a resistance training program. The purpose of this study was twofold: (a) to compare the reliability of 2 separate anthropometric-based field estimations of thigh muscle CSA with that of a more accurate, sophisticated imaging technique (peripheral quantitative computed tomography [pQCT] scanner) and (b) to determine if the field methods would be sensitive enough to detect changes in CSA during a resistance training program. Twenty-five healthy, untrained men completed 8 weeks of resistance training. Cross-sectional area testing occurred twice before the start of training, for reliability and again every 2 weeks during the study. Testing consisted of a pQCT scan of the right thigh followed by circumference and skinfold measurements. Two separate equations (Moritani and deVries [M + D] and Housh multiple regression [HMR]) were used to estimate CSA from the anthropometric data. The M + D and HMR methods demonstrated intraclass correlations of 0.983 and 0.961, respectively, but both significantly underestimated thigh muscle CSA when compared to the pQCT. This error was consistent, however, and consequently, the field methods were able to demonstrate increases in muscle CSA with a pattern similar to those from the pQCT. Thus, these equations can be useful tools to evaluate an athlete's progress toward the goal of increasing muscle CSA. It is the authors' hope that the present study will increase awareness among practitioners of these useful field methods for estimating training-induced changes in muscle CSA. [ABSTRACT FROM AUTHOR]

Energy drink use has grown despite limited research to support efficacy or safety and amid concerns when combined with exercise. The purpose of this study was to assess the effects of 10 weeks of once-daily energy drink consumption or energy drink consumption with exercise on measures of body composition, cardiorespiratory fitness, strength, mood, and safety in previously sedentary males. Thirty-eight males were randomly assigned to energy drink + exercise (EX-A), energy drink (NEX-A), placebo + exercise (EX-B), or placebo (NEX-B). All participants consumed 1 drink per day for 10 weeks; EX-A and EX-B participated in 10 weeks of resistance and endurance exercise. Testing was performed before (PRE) and after (POST) the 10-week intervention. No significant (p > 0.05) changes were observed for body composition, fitness, or strength in NEX-A; however, significantly greater decreases in fat mass and percentage body fat and increases in VO2peak were observed in EX-A versus EX-B. Ventilatory threshold (VT), minute ventilation, VO2 at VT, and power output at VT improved significantly PRE to POST in EX-A but not in EX-B or nonexercising groups. Clinical markers for hepatic, renal, cardiovascular, and immune function, as determined by PRE and POST blood work revealed no adverse effects in response to the energy drink. Mood was not affected by energy drink use. Absent energy restriction or other dietary controls, chronic ingestion of a once-daily low-calorie energy drink appears ineffective at improving body composition, cardiorespiratory fitness, or strength in sedentary males. However, when combined with exercise, preworkout energy drink consumption may significantly improve some physiological adaptations to combined aerobic and resistance training. [ABSTRACT FROM AUTHOR]

Creatine (Cr) loading consists of short-term, high-dosage Cr supplementation and has been shown to increase intramuscular total Cr content. Increases in body weight (BW) have been shown to result from Cr loading, with differences by gender, and increased BW may impact weight-bearing exercise. The critical velocity (CV) test is used to quantify the relationship between total running distance and time to exhaustion. The CV test provides the variable, anaerobic running capacity (ARC), which is an estimate of the anaerobic energy reserves in muscle. The purpose of this study was to examine the effects of gender and Cr loading on ARC. Fifty moderately trained men and women volunteered to participate in this randomized, double-blinded, placebo (PL)-controlled, repeated-measures study. After a familiarization session, a 3-day testing procedure was conducted. A maximal oxygen consumption test VO(2)max) on a treadmill was performed on day 1 to establish the maximum velocity (Vmax) at VO(2)max and to record BW. Days 2 and 3 involved treadmill running at varying percentages of Vmax. Participants were randomly assigned to either the Cr or PL group and received 20 packets of the Cr supplement (1 packet = 5 g Cr citrate, 18 g dextrose) or 20 packets of the PL (1 packet = 18 g dextrose). After consuming 4 packets daily for 5 consecutive days, the 3-day testing procedure was repeated. The male Cr loading group exhibited a 23% higher (p = 0.003) ARC compared to the PL group. Nonsignificant BW increases were found for the Cr groups. These findings suggest that Cr loading may be an effective strategy for improving ARC in men, but not in women, and revealed only nonsignificant increases in BW. Creatine loading may be used before competition by athletes to provide improvements in high-intensity, short-duration activities. [ABSTRACT FROM AUTHOR]

Beta-alanine supplementation has been found to increase intramuscular carnosine, strength, power, volume per training session and a host of other indices of aerobic and anaerobic capacity. However, there is a need to synthesize this research so that the athlete and strength coach alike can optimally benefit from beta-alanine supplementation. The purpose of this review is to provide an analysis of studies conducted on beta-alanine. The review will cover the optimal dosage of beta-alanine; its use in resistance training, intermittent, and endurance-based exercises; and when combined with creatine in trained and untrained individuals. [ABSTRACT FROM AUTHOR]

STUDY DESIGN: Repeated-measures experimental design. OBJECTIVE: To examine the acute effects of different durations of passive stretching on the time course of musculotendinous stiffness (MTS) responses in the plantar flexor muscles. BACKGROUND: Stretching is often implemented prior to exercise or athletic competition, with the intent to reduce the risk of injury via decreases in MTS. METHODS AND MEASURES: Twelve subjects (mean +/- SD age, 24 +/- 3 years; stature, 169 +/- 12 cm; mass, 71 +/- 17 kg) participated in 4 randomly-ordered experimental trials: control with no stretching, 2 min (2[min]), 4 min (4[min]), and 8 min (8[min]) of passive stretching. The passive-stretching trials involved progressive repetitions of 30-second passive stretches, while the control trial involved 15 minutes of resting. MTS assessments were conducted before (prestretching), immediately after (poststretching), and at 10, 20, and 30 minutes poststretching on a Biodex System 3 isokinetic dynamometer. RESULTS: MTS decreased (P<.05) immediately after all stretching conditions (2[min], 4[min], and 8[min]). However, MTS for the 2[min] condition returned to baseline within 10 minutes, whereas MTS after the 4[min] and 8[min] passive-stretching conditions returned to baseline within 20 minutes. CONCLUSIONS: Practical durations of passive stretching resulted in significant decreases in MTS; however, these changes return to baseline levels within 10 to 20 minutes. LEVEL OF EVIDENCE: Level 5. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the acute effects of static versus dynamic stretching on peak torque (PT) and electromyographic (EMG), and mechanomyographic (MMG) amplitude of the biceps femoris muscle (BF) during isometric maximal voluntary contractions of the leg flexors at four different knee joint angles. Fourteen men ((mean +/- SD) age, 25 +/- 4 years) performed two isometric leg flexion maximal voluntary contractions at knee joint angles of 41 degrees , 61 degrees , 81 degrees , and 101 degrees below full leg extension. EMG (muV) and MMG (m x s(-2)) signals were recorded from the BF muscle while PT values (Nm) were sampled from an isokinetic dynamometer. The right hamstrings were stretched with either static (stretching time, 9.2 +/- 0.4 minutes) or dynamic (9.1 +/- 0.3 minutes) stretching exercises. Four repetitions of three static stretching exercises were held for 30 seconds each, whereas four sets of three dynamic stretching exercises were performed (12-15 repetitions) with each set lasting 30 seconds. PT decreased after the static stretching at 81 degrees (p = 0.019) and 101 degrees (p = 0.001) but not at other angles. PT did not change (p > 0.05) after the dynamic stretching. EMG amplitude remained unchanged after the static stretching (p > 0.05) but increased after the dynamic stretching at 101 degrees (p < 0.001) and 81 degrees (p < 0.001). MMG amplitude increased in response to the static stretching at 101 degrees (p = 0.003), whereas the dynamic stretching increased MMG amplitude at all joint angles (p

The purpose of this study was to validate the percentage of body fat (%BF) values estimated from the BOD POD (BP) with those obtained from hydrostatic weighing (HW) in athletic American high school boys. Additionally, the %BF values measured via near-infrared interactance (NIR), bioelectrical impedance (BIA), and skinfold (SF) were compared to HW to determine the validity of these measures. Thirty white boys (mean age +/- SD = 15.8 +/- 1.0 years) who where currently participating in organized sports volunteered to have their %BF estimated. Measurements were obtained from NIR, BP, BIA, and SF in random order and concluded with HW. The findings from the present study indicated that the NIR and BIA instruments produced significant (P < 0.008) constant error (CE) and total error (TE) values that were too large to be of practical value (TE > 4.0%BF). The BP produced a significantly (P < 0.008) higher CE with acceptable TE values compared to HW, but compared to all three SF estimations, the BP TE values were higher. Two of the SF equations were nonsignificant (P > 0.008) and had the lowest TE values compared to HW. These data suggest that the BP can produce acceptable body fat measures for athletic white boys but is not superior to estimates made by the SF equations used in this study. [ABSTRACT FROM AUTHOR]

Presents several letters to the editor. Comments on writer Peter Savage's review of the novels of the writer Arthur Hailey; Remarks on the article "The Role of Management in Science," by Richard O. Mason; Acknowledgement of the journal "Public Administration Review," for publishing the mini-symposium on internships in public administration.

We are often told that "To manage is to control." This phrase fuses two different concepts into synonymy. The bulk of the writing on management-control makes it evident that this construct is not a conjunction of two classes of administrative behavior. It is employed to exclude a distinguishable management function. In the language-in-use, the managerial function is exhausted by the concept of control. This is associated with elaborate technical routines, and an extra- ordinary emphasis on mechanical methods. In examining management curricula and practice, it is reasonable to conclude that all a good manager has to do is to learn a set of control procedures and insure that these are complied with. But control is a function of knowledge, and in uncertain environments knowledge often does not exist. It is necessary therefore, to manage, i.e., assume more flexible responses than are possible in a rigid control mode. The article examines the implications of the management/control confusion as an analogue to Type II statistical error. [ABSTRACT FROM AUTHOR]

It is heartening to see researchers raising the questions that attend public management. We have for too long been satisfied with prescription pronouncements on the proper role of public managers in society. In saying that public management is what public managers do, this author is suggesting that we look to the activity, not the ideology. Public managers exist in and for the society that trains, hires, and pays them. The work of public managers is to manage the public goods they are charged with. The utility of that work is measured in the day-to-day activities that are open to exchange and scrutiny. By encouraging questioning, by increasing the numbers of contact points between society and public managers we enhance the potential for responsible stewardship. Administrative openness and analytic skepticism provide the open window of accountability that is foreclosed by the classification stamp and closed meetings. It is debate and discovery that puts us on the way to refining our theories (models) of what public managers can and perhaps should be doing. There is a distinction between the open character of politics and the private expertise of the administrator. But if the public manager is to serve the well-being of society better, the definition of what public management is must devolve from knowledge of what is, not a series of appeals to vague, misunderstood models of what public management should be. Research in this area is a scientific, not an ideological enterprise. Let the canons of science, not dogma, guide us. [ABSTRACT FROM AUTHOR]

Transgene technology is one of the most heavily relied upon tools in modern biological research. Expression of an exogenous gene within cells, for research and therapeutic applications, nearly always includes promoters and other regulatory sequences. We found that repeats of a non-protein coding transgenic sequence produced profound changes to the behavior of the nematode Caenorhabditis elegans. These changes were produced by a glial promoter sequence but, unexpectedly, major deficits were observed specifically in backward locomotion, a neuron-driven behavior. We also present evidence that this behavioral phenotype is transpromoter copy number-dependent and manifests early in development and is maintained into adulthood of the worm. [ABSTRACT FROM AUTHOR]