bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of exercise on body composition and physical performance measures in college‐aged men and women with intellectual disabilities
Authors: Najm Nadia Marie Ghassan , Jesch Elliot D. 
Published: November 2023

Prevention of chronic disease and improving the quality of life for adults with intellectual disabilities is an area of great concern among many professionals and families. Programs have been created to improve nutrition and physical fitness for individuals with an intellectual disability. However, adapting to the various disabilities and behaviors pose challenging circumstances that makes generating statistical norms about physiological adaptations within the population hard to obtain. The purpose of this study is to assess the physiological adaptations in response to a semester long group‐fitness program in college‐aged men and women with intellectual disabilities. Nine students (20.1± 1.67 y.o.) partook in three group fitness classes and two swim classes each week. Instructors of group fitness class were advised to conduct classes with minimal modifications from their regular classes for the general population. Additionally, students were encouraged to partake in regular physical activity of their choosing outside of the program.The following are the mean differences in measurements of: height (0.078 ± 0.175 inches), weight (4.033 ± 4.656 pounds), BMI (0.367 ± 0.879), percent fat mass (0.28± 0.81%), and the Sit and Reach flexibility test (−0.41 ± 3.006 inches). All measurements were found to be non‐significant, suggesting that a non‐modified fitness program is ineffective at improving physiological adaptions.
Effects of environmental sodium ion concentration on the activity of Na/K‐ATPase. H‐ATPase and Glutamate Dehydrogenase from the gills of fathead minnows (Pimephales promelas)
Authors: Packer Randall K. , Monroe Ian , Wentworth Simon A. , Garvin Jeffrey L. 
Published: November 2023

Na+/K+ ATPase on the basolateral membrane of gill epithelial cells actively transports Na+ from the cell interior to the blood, creating the electrochemical gradient that may help drive secondary active transporters in the apical membrane essential for Na+ influx. H+‐ATPase on apical membranes has been hypothesized to facilitate Na+ uptake. In the renal proximal tubules of mammals glutamate dehydrogenase, GDH, along with phosphate‐dependent glutaminase, deamminates glutamine. Ammonium ions generated exit the apical cell membrane in exchange for Na+ entering the cell via NEH3. We hypothesized that Na/K ATPase, H‐ATPase and GDH activity would be higher in fish acclimated to 1.2 mEq/l [Na+] versus 124 mEq/l environmental [Na+]. Fathead minnows were acclimated to 1.2, 3.2 or 124mE/l Na+ for a minimum of 28 days. Na/K ATPase, H‐ATPase and GDH activities were measured in homogenates of gill tissue. Na/K‐ATPase activity from fish acclimated to 1.4 mE/l (1.99± 0.19 μEq/g protein·hr−1) was significantly (P<0.05) higher than in fish acclimatized to 124 mEq/l (1.41±1.34 μEq/g protein·hr−1). Similarly, GDH activity increased significantly, from 12.32±1.59 to 24.81±2.54 nanoEq/g protein·hr−1g in fish acclimated to 1.2 mEq/l compared to those acclimated to 124 mQ/l Na+. In contrast, H+‐ATPase activity was essentially zero (0.1 ± 0.06 μmoles/mg protein/hr) in fish acclimated to 1.2 mEq/l [Na+] and increased to 0.58±0.10 μmoles/mg protein/hr in fish acclimated to 124 mEq/l [Na+]. These data do not support a role for H+ ATPase in gill Na+ uptake at low environmental [Na+] but do suggest that at low environmental [Na+] ammonium ions generated from deamination of glutamine might exchange at the apical gill membrane for sodium ions entering the cell via NEH3.Support or Funding InformationSupported by the Columbian College of Arts and Sciences, GWU
Historical Perspective of Therapeutic Electricity
Authors: Dias Daniel Penteado Martins , Fazan Rubens , Salgado Helio Cesar 
Published: November 2023

The development and employment of effective methods to treat clinical conditions has affected life quality and expectancy worldwide. There are records showing that the Egyptian civilization, 4,000 years ago, used electricity from electric fish for treating pathologies. Later, Luigi Galvani proposed the concept of bioelectricity in 1780, when he observed that if two metallic instruments touched the sciatic nerve of a toad, there was contraction of the musculature of the hind limbs. The electrical stimulation of tissues has developed noticeably over the past decades. Shelden (1966) has employed electrical stimulation of a branch of the trigeminal nerve for treating an acute pain. It is believed, for instance, that electrical stimulation of neural pathways promotes pain relief by blocking the transmission of physiological electrical signals. The development of new forms of treatment, based on electrical stimulation, depends on three steps: 1) identification of the target tissue; 2) determination of the stimulation pattern; 3) development of appropriate device for the application. Among the clinical conditions currently treated with electrical stimulation we could highlight: depression, epilepsy, hypertension, chronic lower back pain, obesity, and obstructive sleep apnea. Although it seems a challenging technique, there are recent reports (2012) showing that more than 100,000 patients have already been implanted with electrical stimulators in the vagus nerve to treat a variety of diseases. It is clear that the technique is extremely promising but requires joint work by clinicians, neuroscientists and engineers to develop effective protocols for chronic electrical stimulation of tissues.Support or Funding InformationFAPESP (Processes n. 2013/20549‐7 and 2015/20463‐0).
Purification and Subsequent Binding Assay of B‐Cell Activating Factor's Receptor (BAFF‐R) to an Oligonucleotide Aptamer (BAFF‐R1)
Authors: Inman Christopher Fredric 
Published: November 2023

In Non‐Hodgkin's Lymphoma (NHL), it has been shown that the proteins B‐cell activating factor (BAFF), and its receptor (BAFF‐R) are overexpressed by cancerous cells. Upon BAFF trimerization and binding to BAFF‐R on the cellular membrane of malignant B‐cells, the complex endocytoses and starts a signaling cascade that leads to the constitutive expression of oncogenes including STAT3, a transcription factor that causes increased rates of survival and proliferation. This mechanism of action potentially accounts for one possible reason for why these cells resist apoptotic signals. It has also been shown that an RNA aptamer (BAFF‐R1) binds to BAFF‐R with high specificity and high affinity. BAFF‐R1 may be used to transport small interfering RNAs (siRNAs) that can knockout the overexpressed oncogenes through the RNA silencing complex (RISC). The knockout of oncogene mRNA leads to decreased rates of malignant cell survival, and therefore the mechanism of how BAFF‐R1 binds to BAFF‐R for transport into the cell is an interesting area of research and could result in a potential targeted therapy for NHL.To conduct in vitro research involving the interactions between the RNA aptamer and BAFF‐R, it was necessary to synthesize a truncated, extracellular loop of the BAFF‐R protein because integral membrane proteins are difficult to work with. BAFF‐R expression was induced in BL21 E. coli through the pGEX‐KG vector and purified by affinity column chromatography. BAFF‐R was cleaved off the immobilized GST fusion protein with thrombin.An electrophoretic mobility shift assay was performed to generate a binding or saturation curve from which the dissociation constant may be determined. Samples of constant amounts of radiolabeled BAFF‐R1 aptamer and varying amounts of BAFF‐R protein were prepared, and as the protein concentration increased, the base RNA band decreased in intensity and a shifted band representing the aptamer bound to BAFF‐R increased in intensity. By comparing these relative intensities, the saturation curve may be prepared, and the dissociation constant of aptamer binding may be determined.In the future, point mutations will be performed on BAFF‐R and the mutant proteins will be subjected to further electrophoretic mobility shift assays to determine the critical amino acid residues responsible for aptamer binding.Support or Funding InformationDr. Monica Lares provided the support for this project as an opportunity for undergraduate research.
Androgens alter mitophagy in the refed metabolic state
Authors: Steiner Jennifer L , Rossetti Michael L , Gordon Bradley Scott 
Published: November 2023

We previously showed that depletion of androgens via castration increased markers of autophagy activation (i.e. increased LC3 II/I ratio and reduced p62 protein content) in the tibialis anterior (TA) following nutrient consumption. Importantly, this androgen‐mediated effect occurred despite no differences in measures of known putative autophagy regulatory factors. Because of this, it is likely that the sustained elevation in autophagy‐activation was specific to a cellular organelle(s) rather than global autophagy. As others have shown that castration reduced skeletal muscle oxidative capacity, we sought to determine whether autophagic clearance of mitochondria, termed mitophagy, could be contributing to the sustained increase in autophagic markers. To answer this, mice were randomized to sham or castration surgery. After 8 weeks of recovery, all mice were fasted overnight. The next morning, mice remained fasted or were refed for 30 min, and sacrificed 4.5 hr following completion of the refeeding. In the TA muscle, castration reduced mitochondrial protein content as the mitochondria specific proteins cytochrome c oxidase subunit IV (COX IV) and voltage‐dependent anion channel (VDAC) were decreased. An inverse relationship was observed between the protein content of either COX IV or VDAC with p62, suggesting enhanced mitophagy. Castration also reduced the protein expression of the mitophagy regulatory protein, BCL2/adenovirus E1B 19 kDa protein‐interacting protein 3 (BNIP3), despite no change in BNIP3 mRNA suggesting enhanced turnover of the protein during mitophagy. Indeed, direct relationships were observed between the protein content of BNIP3 and either p62, COX IV, or VDAC supporting a role of BNIP3 in castration‐induced mitophagy. Additional analysis also supports a role of Pink1 and Parkin as castration enhanced the mRNA levels of each without a corresponding change in the protein expression, consistent with enhanced turnover of these proteins during mitophagy. Lastly, fasting conditions that enhance global autophagy prevented the castration‐induced reduction in mitochondrial proteins and enhancement of mitophagy markers. In all, these data support a model in which androgens prevent BNIP3/Pink1/Parkin‐mediated mitophagy in skeletal muscle during the refed, but not the fasted, metabolic state.Support or Funding InformationNIH Grant F32 AA‐023422 to JLS
Discovery of a Cell‐penetrating Peptide via Heparin‐binding from Pereskia bleo
Authors: Loo Shining , Kam Antony , Tam James P 
Published: November 2023

Pereskia bleo or rose cactus belongs to the Cactaceae family and is commonly found in South‐east Asia. Traditionally, it is used for cancer treatment, inflammatory diseases and wound healing1. Wound healing involves the extracellular matrix and a complex network of protein‐protein interactions2. Protein‐protein interactions is a vast underexplored space for drug targeting. Disruption of intracellular protein‐protein interactions is largely limited in the ability of molecules capable of specific entry via receptor‐mediated mechanisms and non‐specific entry by membrane penetrations. Extracellular matrices, particularly glycosaminoglycans have been exploited to increase the efficiency of intracellular uptake through non‐receptor mediated entry mechanisms3. Heparin/heparain sulfate, commonly found in the extracellular matrix, can be involved in the cellular uptake of cell‐penetrating peptides3. Here we report the discovery from Pereskia bleo, bleotide pB1, a novel heparin‐binding peptide with cell‐penetrating capabilities. Bleotide pB1 was isolated and purified by a series of liquid chromatography. Transcriptomic and proteomic analyses showed that bleotide pB1 is a 36‐residue peptide with a cystine‐knot arrangement. Similar to known cystine‐knot peptides, bleotide pB1 has high metabolic stability4. Bleotide pB1 is not cytotoxic and hemolytic at concentrations up to 100 μM. Using heparin affinity chromatography and in silico modeling; our results demonstrated that bleotide pB1 is a heparin‐binding peptide. To examine the cell‐penetrating properties of bleotide pB1, N‐terminal TAMRA‐conjugated bleotide pB1 was synthesized by solid‐phase peptide synthesis and oxidative‐folded to the native state. Using flow cytometry and confocal microscopy, we show that TAMRA‐pB1 can be internalized into living cells. CHO‐K1 (wild type) and pgsA‐745 (glycosaminoglycan‐deficient) cells were used to show that the cellular uptake of TAMRA‐pB1 is dependent on glycosaminoglycan expressions. Taken together, this study reports the discovery of a novel heparin‐binding hyper‐stable peptide with cell penetrating properties which could be useful for drug development.Support or Funding InformationThis project was supported in part by the National Research Foundation (NRF‐CRP8‐2011‐05) of the Prime Minister's Office of Singapore.
CFTR‐Associated ATP Release in Neonatal and Adult Skeletal Myoblasts
Authors: Wu Tsz Hin Elton , Ballard Heather Janet 
Published: November 2023

ATP release from contracting skeletal muscle cells stimulates extracellular adenosine formation, which contributes to vasodilation. We previously showed that 1) lactic acid (which is formed by contracting muscle) lowers intracellular pH and stimulates ATP release, and 2) cystic fibrosis transmembrane conductance regulator (CFTR) is activated by low pH and it is involved in acidosis‐induced ATP release.Patients with Cystic Fibrosis commonly have impaired muscle function and reduced exercise tolerance. ATP is a large diameter molecule, and CFTR chloride channel is too narrow for passage of ATP: we investigated whether connexins and/or pannexins were involved in CFTR‐associated ATP release from rat L6 skeletal myoblast cell line (a model for neonatal muscle) and human skeletal muscle myoblasts (HSMM; a model for adult muscle).We measured protein expression with western blot, ATP release by the luciferase assay and large diameter channel opening by Lucifer yellow (LY) uptake.L6 myoblasts expressed Connexin 43 strongly: LY uptake was increased by Ca2+‐free medium; niflumic acid (NA) or lanthanum (Lan3+) inhibited LY uptake in Ca2+‐free medium, suggesting that connexins function as membrane channels in L6 myoblasts. HSMM expressed Pannexin 1 strongly: high K+ stimulated LY uptake, which was inhibited by probenecid (PB) or 10mM carbenoxolone (CBX), indicating that pannexins functioned as membrane channels in adult myoblasts.Lactic acid (LA) increased LY uptake and ATP release in both cell types, confirming that both neonatal and adult muscle cells are capable of acidosis‐induced ATP release. In L6 cells, LA‐induced ATP release was inhibited by NA or Lan3+, but not by PB or 10mM CBX, indicating that it was mediated by connexins but not pannexins. In HSMMs, either Lan3+ or Fast Green‐FCF (FG) could inhibit LA‐induced ATP release, suggesting that either connexins or pannexins could mediate ATP efflux.Forskolin (forsk), alone or with either IBMX or AMP‐PNP, an ATP analog that locks CFTR in its open state, strongly stimulated ATP release from HSMMs and L6 cells, confirming that CFTR activation could stimulate ATP release from neonatal or adult myoblasts. In HSMMs, forsk/AMP‐PNP‐induced ATP release was inhibited by FG but not Lan3+, suggesting that CFTR activation stimulates ATP release through pannexins but not connexins. In L6 cells, forsk/AMP‐PNP‐stimulated ATP release was about 75% inhibited by Lan3+, suggesting that it is largely mediated by connexins.These data suggest that CFTR‐associated ATP release from muscle cells can be mediated by connexins or pannexins. Further investigation is required to determine the mechanism by which CFTR regulates the opening of connexin and pannexin channel.
The role of hydrogen peroxide production in skeletal muscle dysfunction following nerve crush.
Authors: Staunton Caroline Amy , Pollock Natalie , Vasilaki Aphrodite , Barrett‐Jolley Richard , McArdle Anne , Jackson Malcolm J 
Published: November 2023

Age‐related loss of muscle mass and function greatly influences the quality of life of older people. Denervation, mitochondrial hydrogen peroxide (H202) production and elevated pro‐inflammatory cytokines levels are thought to play a substantial role in this muscle dysfunction and to be key contributors to frailty in the elderly.A substantial body of evidence links reactive oxygen species (ROS), and in particular mitochondrial H202 production, with skeletal muscle dysfunction. This research area has been limited by the availability of accurate and specific methods for H202 detection. We have therefore examined the use of HyPer2 as a specific fluorescent probe for H202 in muscle in vivo following transfection using rAAV6.The aim of this study was (1) to use intra‐vital imaging to examine morphological changes in the structure of peripheral axons and neuromuscular junctions following peroneal nerve crush in Thy1‐CFP mice, and (2) to monitor in parallel the levels of H202 in the cytosol of denervated muscle fibres in muscles transfected with HyPer2‐Cyto in a rAAV6 vector at 3, 7 and 21 days post‐nerve injury using intra‐vital imaging. Peroneal nerve crush was used as a model that potentially reflects the ageing process due to the reversible nature of the denervation. To complement the rAAV6‐HyPer2‐Cyto in vivo study, mitochondrial H202 generation was also assessed using the Amplex red assay ex vivo in small bundles of permeabilised muscle fibres from the anterior tibilas (AT) muscles from Thy1‐CFP mice which underwent the same nerve crush procedure.Following the peroneal nerve crush an increased H202 content was seen in fibres of the anterior tibialis muscle of adult mice in vivo compared with sham control mice using the rAAV6‐Hyper2‐Cyto probe. The temporal profile of changes in H202 content was obtained over a 21 day period post nerve crush by repeated examination of the same mice.This work expands on previous studies using a peroneal axotomy model where adult mice were shown to have an increased mitochondrial peroxide production ex vivo2 and data from our laboratory that have further demonstrated that this peroxide generation by muscle remained significantly elevated after full denervation. Further data also suggest that increased mitochondrial peroxide generation may mediate cytokine production by muscle cells1 and our group has shown that following denervation, mRNA from AT muscles show IL‐6, MCP1 and RANTES are significantly increased from control mice.These data provide additional insight into the generation of H2O2 in muscle following nerve damage and together with other data will allow further exploration of how changes in neuromuscular junction integrity prevent neuromuscular transmission and the relationship of this to muscle H202 levels.Support or Funding InformationThis work was supported by the UK Medical Research Council.
Cigarette smoke exposure induces diaphragm atrophy that partially regresses following cessation
Authors: Foster Andrew , Stampfli Martin R. , Simpson Jeremy A. 
Published: November 2023

Atrophy is well known to occur in the diaphragm and limb muscles of patients with chronic obstructive pulmonary disease (COPD), a disease predominantly caused by cigarette smoke exposure. Interestingly, non‐COPD smokers also exhibit limb muscle atrophy; a finding that implicates cigarette smoke as a cause of atrophy. This has been substantiated in animal models demonstrating that limb muscle atrophy occurs early following cigarette smoke exposure and prior to overt lung dysfunction. These studies also indicate that pro‐atrophy pathways are partially reversed upon the cessation of cigarette smoke exposure suggesting possible regression of atrophy. However, the effect of cigarette smoke exposure and cessation, on diaphragm muscle atrophy, has not been investigated. Thus, the overall objective of this project is to investigate the effect of cigarette smoke exposure on the development of diaphragm atrophy in mice. We hypothesize that cigarette smoke exposure in mice will induce diaphragm atrophy; further, will be reversed following cessation.MethodsBALB/c mice were repeatedly exposed to room air or cigarette smoke twice a day, 5 days/week. To assess the pathological development of diaphragm atrophy, mice were exposed to either 8 or 24 weeks of cigarette smoke. Following initial exposure, a subset of mice were switched to room air for an additional 8 weeks to evaluate the effect of cigarette smoke cessation. All groups were compared to non‐smoking controls. At the time of sacrifice, mice were formalin fixed and diaphragm tissue was removed for histological evaluation of diaphragm myocyte cross sectional area (CSA).ResultsIn comparison to non‐smoking controls, diaphragm CSA was reduced by 40% following 8 weeks cigarette smoke exposure and did not worsen by 24 weeks. Median diaphragm CSA in 8 and 24 week exposure groups were 220um2 and 215um2 respectively, which was significantly reduced from 370um2 in non‐smoking controls (p<0.05). In mice switched to room air, diaphragm CSA was reduced by 20% as compared to non‐smoking controls; 298um2 vs. 370um2 respectively.ConclusionsHere we demonstrate that diaphragm atrophy is induced early following cigarette smoke exposure and does not worsen with prolonged experience. Further, our data indicate that the cessation of cigarette smoke exposure partially regresses diaphragm atrophy. In future work we aim to identify the intracellular mechanisms through which diaphragm atrophy develops in response to cigarette smoke exposure.Support or Funding InformationCanadian Thoracic Society/ Canadian Lung Association