Nonlinear elasticity and short-range mechanical coupling govern the rate and symmetry of mouth opening in Hydra.

Hydra has a tubular bilayered epithelial body column with a dome-shaped head on one end and a foot on the other. Hydra lacks a permanent mouth: its head epithelium is sealed. Upon neuronal activation, a mouth opens at the apex of the head which can exceed the body column diameter in seconds, allowing Hydra to ingest prey larger than itself. While the kinematics of mouth opening are well characterized, the underlying mechanism is unknown. We show that Hydra mouth opening is generated by independent local contractions that require tissue-level coordination. We model the head epithelium as an active viscoelastic nonlinear spring network. The model reproduces the size, timescale and symmetry of mouth opening. It shows that radial contractions, travelling inwards from the outer boundary of the head, pull the mouth open. Nonlinear elasticity makes mouth opening larger and faster, contrary to expectations. The model correctly predicts changes in mouth shape in response to external forces. By generating innervated : nerve-free chimera in experiments and simulations, we show that nearest-neighbour mechanical signalling suffices to coordinate mouth opening. Hydra mouth opening shows that in the absence of long-range chemical or neuronal signals, short-range mechanical coupling is sufficient to produce long-range order in tissue deformations.

Daily Relationship Functioning and Disordered Eating Behaviors Among Sexual Minority Women in Same-Sex Relationships.

BACKGROUND AND PURPOSE: The present study aimed to examine associations between different types of relationship functioning and disordered eating behaviors (DEBs) in the everyday lives of sexual minority women in same-sex relationships-an at-risk population that has not been assessed in this context. METHODS: Participants included 321 young sexual minority women (Mage = 27.56, SD = 3.67) in same-sex relationships who completed surveys assessing their daily relationship functioning and DEB use each day for a 14-day daily diary period. Multilevel structural equation modeling was used to examine daily-, person-, and couple-level associations among women's daily relationship functioning (general relationship functioning, positive and negative relational behaviors they and, separately, their partners engaged in) and DEBs (overeating, loss of control eating, emotional eating, and dietary restriction). RESULTS: Results generally indicated that more positive and less negative daily relationship functioning across all assessed constructs was associated with less same-day emotional eating. In contrast, associations between all daily relationship functioning constructs and loss of control eating were not significant, nor were any relationship functioning-DEB associations at the couple level. More circumscribed patterns of association were identified for associations between the relationship functioning constructs, and overeating and dietary restriction. CONCLUSIONS: Collectively, these findings provide insight into how aspects of daily relationship functioning map onto sexual minority women's daily engagement in DEBs that are linked to poor health long-term, and directions for future research and clinical practice that may warrant consideration moving forward to help advance the evidence-base and care for this historically overlooked and underserved population.

The present study examined associations between different types of relationship functioning (e.g., general relationship functioning, positive and negative relational behaviors that participants and their partners engaged in during their interactions with one another) and disordered eating behaviors (DEBs) in the everyday lives of sexual minority women in same-sex relationships. Results generally indicated that on days when women reported more positive and less negative daily relationship functioning, they also reported less emotional eating that day. In contrast, associations between different types of daily relationship functioning and loss of control eating were not significant. Furthermore, associations between different types of daily relationship functioning relative to overeating and dietary restriction varied based on the type of relationship functioning and DEB under consideration. Collectively, these findings provide insight into how different types of daily relationship functioning map onto sexual minority women's daily engagement in DEBs that are linked to poor health long-term. These findings also provide directions for future research and clinical practice that may warrant consideration moving forward to help advance the evidence base and care for this historically overlooked and underserved population.

The effect of increasing exercise in the intellectually disabled community.

BACKGROUND: Intellectually disabled individuals have been observed to lead sedentary lifestyles resulting in poor health. Physical fitness has been positively correlated to better health outcomes with small changes in fitness translating to major health changes among unfit older adults with intellectual disability. However, there is currently no literature on safe exercise regimens for the intellectually disabled population. METHODS: In this article, a retrospective review was conducted using the Special Olympics Athlete database and analyzed the mean differences of various performance metrics based on self-reported exercise frequency. RESULTS: These results demonstrated that those who exercised daily performed significantly better in flexibility, static balance and functional strength as compared to those who did not exercise. No statistically significant differences were found among athletes and self-reported exercise frequency for aerobic fitness. CONCLUSION: Overall, these findings suggest that 3-6 days-a-week of moderate exercise would be a recommended exercise dose to see significant improvement in performance and physiological adaptations.

Preliminary evidence on cigarette nicotine reduction with concurrent access to an e-cigarette: Manipulating cigarette nicotine content, e-liquid nicotine content, and e-liquid flavor availability.

The reinforcing characteristics of e-cigarettes could moderate the impact of reducing cigarette nicotine content. In this study, people who smoke daily were recruited from North Carolina and Pennsylvania (US) in 2018 and 2019. Within a randomized 2 × 2 × 2 factorial design, participants received investigational cigarettes and an e-cigarette for 12 weeks. Cigarette nicotine content was very low (0.4 mg/g of tobacco; VLNC) or normal (15.8 mg/g; NNC). E-liquids were 0.3% ("low") or 1.8% ("moderate") freebase nicotine, and available in tobacco flavors or tobacco, fruit, dessert and mint flavors. Study recruitment concluded before reaching the planned sample size (N = 480). Fifty participants were randomized and 32 completed the study. We found that randomization to VLNC, relative to NNC cigarettes, reduced self-reported cigarettes per day (CPD; mean difference: -12.96; 95% CI: -21.51, -4.41; p = 0.005); whereas e-liquid nicotine content and flavor availability did not have significant effects. The effect of cigarette nicotine content was larger in the moderate vs. low nicotine e-liquid groups and in the all flavors versus tobacco flavors e-liquid groups; tests of the interaction between e-liquid characteristics and cigarette nicotine content were not significant. Biomarkers of smoke exposure at Week 12 did not differ across conditions, which may reflect variability in adherence to only using VLNC cigarettes. In conclusion this study offers preliminary evidence that the extent to which cigarette nicotine reduction decreases smoking may depend on the reinforcing characteristics of alternative products, including the available nicotine contents and flavors of e-cigarettes.

Early Changes in Puffing Intensity When Exclusively Using Open-Label Very Low Nicotine Content Cigarettes.

INTRODUCTION: In response to reducing cigarette nicotine content, people who smoke could attempt to compensate by using more cigarettes or by puffing on individual cigarettes with greater intensity. Such behaviors may be especially likely under conditions where normal nicotine content (NNC) cigarettes are not readily accessible. The current within-subject, residential study investigated whether puffing intensity increased with very low nicotine content (VLNC) cigarette use, relative to NNC cigarette use, when no other nicotine products were available. AIMS AND METHODS: Sixteen adults who smoke daily completed two four-night hotel stays in Charleston, South Carolina (United States) in 2018 during which only NNC or only VLNC cigarettes were accessible. We collected the filters from all smoked cigarettes and measured the deposited solanesol to estimate mouth-level nicotine delivery per cigarette. These estimates were averaged within and across participants, per each 24-h period. We then compared the ratio of participant-smoked VLNC and NNC cigarette mouth-level nicotine with the ratio yielded by cigarette smoking machines (when puffing intensity is constant). RESULTS: Average mouth-level nicotine estimates from cigarettes smoked during the hotel stays indicate participants puffed VLNC cigarettes with greater intensity than NNC cigarettes in each respective 24-h period. However, this effect diminished over time (p < .001). Specifically, VLNC puffing intensity was 40.0% (95% CI: 29.9, 53.0) greater than NNC puffing intensity in the first period, and 16.1% (95% CI: 6.9, 26.0) greater in the fourth period. CONCLUSION: Average puffing intensity per cigarette was elevated with exclusive VLNC cigarette use, but the extent of this effect declined across four days. IMPLICATIONS: In an environment where no other sources of nicotine are available, people who smoke daily may initially attempt to compensate for cigarette nicotine reduction by puffing on individual cigarettes with greater intensity. Ultimately, the compensatory behavior changes required to achieve usual nicotine intake from VLNC cigarettes are drastic and unrealistic. Accordingly, people are unlikely to sustain attempts to compensate for very low cigarette nicotine content.

Slip slidin' away: Bristle-driven gliding by Tetradesmus deserticola (Chlorophyta) in microfluidic chambers.

Microalgae within the Scenedesmaceae are often distinguished by spines, bristles, and other wall characteristics. We examined the dynamic production and chemical nature of bristles extruded from the poles of Tetradesmus deserticola previously isolated from microbiotic crust. Rapidly growing cells in a liquid growth medium were established in polydimethylsiloxane microfluidic chambers specially designed to maintain aerobic conditions over time within a chamber 6-12 µm deep. This geometry enabled in-focus imaging of single cells over long periods. Differential interference contrast (DIC) imaging revealed that after multiple fission of mother cells, the newly released, lemon-shaped daughter cells began extruding bristles from each pole. In some instances, the bristles became stuck to either the glass floor or polydimethylsiloxane (PDMS) walls of the chamber, and the force by which the new bristle was extruded was sufficient to propel the cells across the field of view at ~1.2 µm · h-1 . Confocal fluorescence and DIC imaging of cells stained with pontamine fast scarlet and calcofluor, and treated with proteinase K, suggested that bristles are proteinaceous and may also host carbohydrate modifications. The polar bristles extruded by this desert-derived T. deserticola may simply be relics of bristles produced by an aquatic ancestor for flotation or predator deterrence. But, their tendency to attach to glass (silicate) and/or PDMS surfaces suggests a potential role in tethering cells in place or binding soil particles. T. deserticola is closely related to T. obliquus, which is of interest for biofuels development; extruded bristles in T. deserticola may offer tethers for industrial use of these stress-tolerant algae.

Clinical Practice Patterns of Isthmic Spondylolysis in Young Athletes: A Survey of Pediatric Research in Sports Medicine Members.

ABSTRACT: Isthmic spondylolysis is a common cause of back pain in young athletes. The condition presents to numerous medical providers who employ a variety of different practices in diagnosis and management. The purpose of this study was twofold: to review the literature of diagnosis and management of the young athlete with isthmic spondylolysis and to survey Pediatric Research in Sports Medicine (PRiSM) members during the 2021 PRiSM Annual Meeting on practice patterns of diagnosis and management of the young athlete with isthmic spondylolysis. The response rate was 27%. Per respondents: 24% obtain oblique radiographs; 90% use magnetic resonance imaging as the advanced imaging modality; 60% treat with bracing; 57% recommend rest prior to physical therapy (PT); 53% prescribe return to sport activity restrictions. Although there are similarities in the diagnosis of isthmic spondylolysis in young athletes, this survey confirmed variability in management, especially bracing, timing of PT and return to sport activity restrictions.

Physical Literacy in Elementary Physical Education: A Survey of Fundamental Movement Skill Practice Patterns.

PURPOSE: To describe fundamental movement skill (FMS) practice patterns in the elementary physical education (PE) curriculum. METHODS: A cross-sectional survey was sent to PE teachers of grades 1 through 6. Sixty-eight responses were included for analysis. RESULTS: Only 38.2% of teachers taught all 12 FMS components. Compared with PE teachers for grades 4 to 6, a significantly higher proportion of PE teachers for grades 1 to 3 taught all 12 FMS and used direct instruction methods. For children falling behind, only 8.8% reported referring to an exercise program and no PE teacher sought a health care referral. A video abstract can be found in Supplemental Digital Content 1 (available at: http://links.lww.com/PPT/A342).

Where You Lead, I Will Follow: Exploring Sibling Similarity in Brain and Behavior During Risky Decision Making.

This exploratory study examined whether social learning increases similarity in adolescent siblings' behavior and neural patterns during risky decision making. Participants included 86 adolescents (43 sibling dyads; younger siblings: Mage  = 12.2 years; 22 females; older siblings: Mage  = 14.6 years; 20 females) who completed questionnaires, and a decision-making task during an fMRI scan. Younger siblings became more similar to their older siblings' risky decision making after observing their older sibling take risks). Younger siblings who reported greater modeling of their older sibling, and less differentiation from them, showed increased neural similarity to their older siblings in the ventromedial prefrontal cortex, and the right anterior insula and ventral striatum, respectively. These findings highlight siblings as salient social agents in how adolescents process risky decision making.

Death Attitudes, Palliative Care Self-efficacy, and Attitudes Toward Care of the Dying Among Hospice Nurses.

Previous research has linked death attitudes, palliative care self-efficacy, and attitudes toward care of the dying among nursing students and other nursing samples, but not among hospice nurses. The purpose of this study was to investigate these relationships among hospice nurses (N = 90). More positive attitudes toward care of the dying were associated with lower fear of death and death avoidance as well as higher neutral acceptance and escape acceptance, but not with approach acceptance. More positive attitudes toward care of the dying was associated with perceived capability to answer end-of-life concerns, but not with perceived capability to respond to end-of-life symptoms. Clinical interventions seeking to improve attitudes toward care of the dying among hospice nurses may be most effective by targeting death attitudes and improving self-efficacy in the area of discussing end-of-life concerns with patients.

A Clinical Review of Slipping Rib Syndrome.

ABSTRACT: Slipping rib syndrome is pain created at the lower, anterior border of the rib cage when performing upper-extremity activities, coughing, laughing, or leaning over. Defects in the costal cartilage of ribs 8 to 10 result in increased movement of the ribs, impinging soft tissue and intercostal nerves. Advancements have been made in the diagnosis of slipping rib syndrome by dynamic ultrasound. Ultrasound can identify abnormalities in the rib and cartilage anatomy, as well as soft tissue swelling. Although the mainstays of treatment continue to be reassurance, nonsteroidal anti-inflammatory drugs, physical therapy, intercostal nerve injections, osteopathic manipulative treatment, surgery for refractory pain, and botulinum toxin injections have been attempted, and there may be a role for prolotherapy in treatment. Surgical techniques are being examined secondary to recurrence of pain following resection. The hooking maneuver and surgery remain important for identification and treatment, respectively.

Discovery and properties of a new indigoid structure type based on dimeric cis-indigos.

Reactions of indigo with quinones in the presence of sodium hydride leads unexpectedly to products containing two indigo subunits; one indigo is featured in a cis configuration and fused via its indole nitrogen atoms to a second indigo at the central C-C bond of the latter. Structural, optical, and redox properties of the new compounds are reported.

Macrophage-Associated Lipin-1 Enzymatic Activity Contributes to Modified Low-Density Lipoprotein-Induced Proinflammatory Signaling and Atherosclerosis.

OBJECTIVE: Macrophage proinflammatory responses induced by modified low-density lipoproteins (modLDL) contribute to atherosclerotic progression. How modLDL causes macrophages to become proinflammatory is still enigmatic. Macrophage foam cell formation induced by modLDL requires glycerolipid synthesis. Lipin-1, a key enzyme in the glycerolipid synthesis pathway, contributes to modLDL-elicited macrophage proinflammatory responses in vitro. The objective of this study was to determine whether macrophage-associated lipin-1 contributes to atherogenesis and to assess its role in modLDL-mediated signaling in macrophages. APPROACH AND RESULTS: We developed mice lacking lipin-1 in myeloid-derived cells and used adeno-associated viral vector 8 expressing the gain-of-function mutation of mouse proprotein convertase subtilisin/kexin type 9 (adeno-associated viral vector 8-proprotein convertase subtilisin/kexin type 9) to induce hypercholesterolemia and plaque formation. Mice lacking myeloid-associated lipin-1 had reduced atherosclerotic burden compared with control mice despite similar plasma lipid levels. Stimulation of bone marrow-derived macrophages with modLDL activated a persistent protein kinase Cα/ßII-extracellular receptor kinase1/2-jun proto-oncogene signaling cascade that contributed to macrophage proinflammatory responses that was dependent on lipin-1 enzymatic activity. CONCLUSIONS: Our data demonstrate that macrophage-associated lipin-1 is atherogenic, likely through persistent activation of a protein kinase Cα/ßII-extracellular receptor kinase1/2-jun proto-oncogene signaling cascade that contributes to foam cell proinflammatory responses. Taken together, these results suggest that modLDL-induced foam cell formation and modLDL-induced macrophage proinflammatory responses are not independent consequences of modLDL stimulation but rather are both directly influenced by enhanced lipid synthesis.

Diagnosis and Treatment of Slipping Rib Syndrome.

OBJECTIVE: (1) To investigate the clinical presentation, diagnosis, and treatment of slipping rib syndrome in athletes; (2) to investigate the hooking maneuver for diagnosis of slipping rib syndrome. DESIGN: Retrospective chart review of 362 athletes with rib pain. SETTING: Pediatric-based sports medicine clinic between January 1, 1999, and March 1, 2014. PATIENTS: Costochondritis, Tietze, fractures, rib tip syndrome, and unclear diagnoses were excluded. Athletes were included who had a palpable rib subluxation, mechanical rib symptom, positive hooking maneuver, or resolution of pain after the resection of a slipping rib segment. MAIN OUTCOME MEASURES: Slipping rib syndrome is associated with athletic performance. RESULTS: Fifty-four athletes were diagnosed with slipping rib syndrome, of which 38 (70%) were females. Mean age at presentation was 19.1 years (range 4-40 years). Mean number of previous specialist consultations per athlete was 2.3 and mean time from symptom onset to diagnosis was 15.4 months. The hooking maneuver was attempted 21 times (38.9%). Unilateral symptoms presented in 49 athletes (90.7%). The most symptomatic rib was the 10th, affecting 24 athletes (44.4%), eighth and ninth were affected in 17 athletes (31.5%) each. Most, 39 (72.2%), reported insidious onset of symptoms. Running, rowing, lacrosse, and field hockey were frequently associated activities. Twelve athletes had psychiatric diagnoses (22.2%), 10 (19.2%) were hypermobile. Sixty-six total imaging studies were performed. The most successful treatment options included: osteopathic manipulative treatment (71.4%), surgical resection (70%), and diclofenac gel (60%). CONCLUSIONS: Most athletes with slipping rib syndrome were active females with insidious onset of unilateral pain, a high prevalence of hypermobility and prolonged pain. The hooking maneuver was underused.

Whether to push or pull? Nicotine reduction and non-combusted alternatives - Two strategies for reducing smoking and improving public health.

Combustible cigarettes remain the most harmful and addictive tobacco product, and reducing the prevalence of smoking continues to be a critical public health goal. While nicotine is the constituent primarily responsible for addiction to cigarettes, most of the harm associated with smoking comes from byproducts of tobacco combustion. Recently, two different approaches for reducing the harms of smoking have emerged, both of which focus on breaking the link between the addiction to nicotine and the harms caused by smoking. First, the addictive potential of cigarettes could be minimized by requiring a large reduction in the nicotine content of cigarettes. Evidence for a nicotine reduction policy thus far shows that the use of very low nicotine content cigarettes results in a reduction in the number of cigarettes people smoke per day and a reduction in cigarette dependence. Second, emerging alternative nicotine delivery systems (ANDS) like electronic cigarettes may provide sufficient nicotine to act as substitutes for cigarettes while delivering much lower levels of toxicants. Evidence suggests that the emergence of ANDS has increased the percentage of smokers who are able to quit. The present paper will briefly review the evidence for each of these approaches, and consider what contemporary reinforcement and addiction theories can tell us about their likely success. We argue that the most effective endgame approach is one that pursues both nicotine reduction and alternative nicotine delivery systems as complementary.

White matter hyperintensities are associated with disproportionate progressive hippocampal atrophy.

This study investigates relationships between white matter hyperintensity (WMH) volume, cerebrospinal fluid (CSF) Alzheimer's disease (AD) pathology markers, and brain and hippocampal volume loss. Subjects included 198 controls, 345 mild cognitive impairment (MCI), and 154 AD subjects with serial volumetric 1.5-T MRI. CSF Aß42 and total tau were measured (n = 353). Brain and hippocampal loss were quantified from serial MRI using the boundary shift integral (BSI). Multiple linear regression models assessed the relationships between WMHs and hippocampal and brain atrophy rates. Models were refitted adjusting for (a) concurrent brain/hippocampal atrophy rates and (b) CSF Aß42 and tau in subjects with CSF data. WMH burden was positively associated with hippocampal atrophy rate in controls (P = 0.002) and MCI subjects (P = 0.03), and with brain atrophy rate in controls (P = 0.03). The associations with hippocampal atrophy rate remained following adjustment for concurrent brain atrophy rate in controls and MCIs, and for CSF biomarkers in controls (P = 0.007). These novel results suggest that vascular damage alongside AD pathology is associated with disproportionately greater hippocampal atrophy in nondemented older adults. © 2016 The Authors Hippocampus Published by Wiley Periodicals, Inc.

Characterization of a Novel Hepadnavirus in the White Sucker (Catostomus commersonii) from the Great Lakes Region of the United States.

UNLABELLED: The white sucker Catostomus commersonii is a freshwater teleost often utilized as a resident sentinel. Here, we sequenced the full genome of a hepatitis B-like virus that infects white suckers from the Great Lakes Region of the United States. Dideoxy sequencing confirmed that the white sucker hepatitis B virus (WSHBV) has a circular genome (3,542 bp) with the prototypical codon organization of hepadnaviruses. Electron microscopy demonstrated that complete virions of approximately 40 nm were present in the plasma of infected fish. Compared to avi- and orthohepadnaviruses, sequence conservation of the core, polymerase, and surface proteins was low and ranged from 16 to 27% at the amino acid level. An X protein homologue common to the orthohepadnaviruses was not present. The WSHBV genome included an atypical, presumptively noncoding region absent in previously described hepadnaviruses. Phylogenetic analyses confirmed WSHBV as distinct from previously documented hepadnaviruses. The level of divergence in protein sequences between WSHBV and other hepadnaviruses and the identification of an HBV-like sequence in an African cichlid provide evidence that a novel genus of the family Hepadnaviridae may need to be established that includes these hepatitis B-like viruses in fishes. Viral transcription was observed in 9.5% (16 of 169) of white suckers evaluated. The prevalence of hepatic tumors in these fish was 4.9%, and only 2.4% of fish were positive for both virus and hepatic tumors. These results are not sufficient to draw inferences regarding the association of WSHBV and carcinogenesis in white sucker. IMPORTANCE: We report the first full-length genome of a hepadnavirus from fishes. Phylogenetic analysis of this genome indicates divergence from genomes of previously described hepadnaviruses from mammalian and avian hosts and supports the creation of a novel genus. The discovery of this novel virus may better our understanding of the evolutionary history of hepatitis B-like viruses of other hosts. In fishes, knowledge of this virus may provide insight regarding possible risk factors associated with hepatic neoplasia in the white sucker. This may also offer another model system for mechanistic research.

A critical analysis of unplanned ICU transfer within 48 hours from ED admission as a quality measure.

HYPOTHESIS: Unplanned intensive care unit (ICU) transfer (UIT) within 48 hours of emergency department (ED) admission increases morbidity and mortality. We hypothesized that a majority of UITs do not have critical interventions (CrIs) and that CrI is associated with worse outcomes. OBJECTIVE: The objective of the study is to characterize all UITs (including patients who died before ICU transfer), the proportion with CrI, and the effect of having CrI on mortality. DESIGN: This is a single-center, retrospective cohort study of UITs within 48 hours from 2008 to 2013 at an urban academic medical center and included patients 18 years or older without advanced directives (ADs). Critical intervention was defined by modified Delphi process. Data included demographics, comorbidities, reasons for UIT, length of stay, CrIs, and mortality. We calculated descriptive statistics with 95% confidence intervals (CIs). RESULTS: A total of 837 (0.76%) of 108 732 floor admissions from the ED had a UIT within 48 hours; 86 admitted patients died before ICU. We excluded 23 ADs, 117 postoperative transfers, 177 planned ICU transfers, and 4 with missing data. Of the 516 remaining, 65% (95% CI, 61%-69%) received a CrI. Unplanned ICU transfer reasons are as follows: 33 medical errors, 90 disease processes not present on arrival, and 393 clinical deteriorations. Mortality was 10.5% (95% CI, 8%-14%), and mean length of stay was 258 hours (95% CI, 233-283) for those with CrI, whereas the mortality was 2.8% (95% CI, 1%-6%) and mean length of stay was 177 hours (95% CI, 157-197) for those without CrI. CONCLUSIONS: Unplanned ICU transfer is rare, and only 65% had a CrI. Those with CrI had increased morbidity and mortality.