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Frontiers in Physiology 2024Few US Marines earn perfect 300 scores on both their Physical Fitness Test (PFT) and Combat Fitness Test (CFT). The number 300 invokes the legendary 300 Spartans that...
UNLABELLED
Few US Marines earn perfect 300 scores on both their Physical Fitness Test (PFT) and Combat Fitness Test (CFT). The number 300 invokes the legendary 300 Spartans that fought at the Battle of Thermopylae, which inspired high physical fitness capabilities for elite ground forces ever since.
PURPOSE
Determine distinguishing characteristics of the "300 Marines" (perfect PFT and CFT scores) that may provide insights into the physical and physiological requirements associated with this capability. These tests have been refined over time to reflect physical capabilities associated with Marine Corps basic rifleman performance.
MATERIALS AND METHODS
Data were analyzed from US Marines, including 497 women (age, 29 ± 7 years; height 1.63 ± 0.07 m; body mass, 67.4 ± 8.4 kg) and 1,224 men (30 ± 8 years; 1.77 ± 0.07 m; 86.1 ± 11.1 kg). Marines were grouped by whether they earned perfect 300 scores on both the PFT and CFT (300 Marines) or not. We analyzed group differences in individual fitness test events and body composition (dual-energy x-ray absorptiometry).
RESULTS
Only 2.5% ( = 43) of this sample earned perfect PFT and CFT scores ( = 21 women; = 22 men). Compared to sex-matched peers, 300 Marines performed more pull-ups, with faster three-mile run, maneuver-under-fire, and movement-to-contact times (each < 0.001); 300 Marines of both sexes had lower fat mass, body mass index, and percent body fat (each < 0.001). The lower percent body fat was explained by greater lean mass ( = 0.041) but similar body mass ( = 0.085) in women, whereas men had similar lean mass ( = 0.618), but lower total body mass ( = 0.025).
CONCLUSION
Marines earning perfect PFT and CFT scores are most distinguished from their peers by their maneuverability, suggesting speed and agility capabilities. While both sexes had considerably lower percent body fat than their peers, 300 Marine women were relatively more muscular while men were lighter.
PubMed: 38957215
DOI: 10.3389/fphys.2024.1406749 -
Frontiers in Physiology 2024
PubMed: 38957214
DOI: 10.3389/fphys.2024.1441872 -
Frontiers in Integrative Neuroscience 2024This paper proposes a new model of stress that integrates earlier models and adds insights from developmental psychology. Previous models describe the behavioral and...
This paper proposes a new model of stress that integrates earlier models and adds insights from developmental psychology. Previous models describe the behavioral and physical effects of stress events, but have not explained the translation of experiences into stress itself. The Developmental Model of Stress shows how psychosocial developmental challenges in childhood create persistent negative beliefs and behaviors that increase threat perception and maladaptive stress responses. These developmental challenges produce early psychological and physiological predispositions for increased stress responses over time. Ongoing stress leads to dysregulation of physical stress-response systems (allostatic load), which is associated with multiple diseases. High allostatic load provides the necessary preconditions for the diathesis-stress model, which says the addition of an acute stressor to a weakened or predisposed system can lead to disease development. The paper also documents the evolving measurement of stress to better understand the stress-disease relationship, helping to resolve conflicting results between studies. The Developmental Model of Stress was combined with clinician insight and patient reports to build an integrative framework for understanding the role of stress in the development and progression of multiple sclerosis (MS). It includes the first mapping of maladaptive beliefs and behaviors arising from developmental challenges that are common to people with MS. An initial comparison shows these may be distinct from those of people with other chronic diseases. These beliefs and behaviors form the predisposing factors and contribute to the triggering factors, which are the acute stressors triggering disease onset. These often took two forms, a prolonged incident experienced as feeling trapped or stuck, and threat of a breach in a relationship. The reinforcing factors add the stress of a chronic disease with a poor prognosis and seemingly random symptom fluctuation, still managed with the same beliefs and behaviors developed in childhood, increasing physiological dysregulation and symptom severity. A pilot study is described in which these three categories of stress factors in MS were explicitly addressed. This study noted clinically important improvements in physical and mental well-being, providing preliminary support for the Developmental Model. Future research might expand on the pilot using a more robust sample and design.
PubMed: 38957213
DOI: 10.3389/fnint.2024.1365672 -
International Journal of Nanomedicine 2024Salidroside (SAL) is the most effective component of , a traditional Chinese medicine. Cryptotanshinone (CT) is the main fat-soluble extract of , exhibiting considerable...
BACKGROUND
Salidroside (SAL) is the most effective component of , a traditional Chinese medicine. Cryptotanshinone (CT) is the main fat-soluble extract of , exhibiting considerable potential for application in osteogenesis. Herein, a polycaprolactone/gelatin nanofiber membrane loaded with CT and SAL (PSGC membrane) was successfully fabricated via coaxial electrospinning and characterized.
METHODS AND RESULTS
This membrane capable of sustained and controlled drug release was employed in this study. Co-culturing the membrane with bone marrow mesenchymal stem cells and human umbilical vein endothelial cells revealed excellent biocompatibility and demonstrated osteogenic and angiogenic capabilities. Furthermore, drug release from the PSGC membrane activated the Wnt/β-catenin signaling pathway and promoted osteogenic differentiation and vascularization. Evaluation of the membrane's vascularization and osteogenic capacities involved transplantation onto a rat's subcutaneous area and assessing rat cranium defects for bone regeneration, respectively. Microcomputed tomography, histological tests, immunohistochemistry, and immunofluorescence staining confirmed the membrane's outstanding angiogenic capacity two weeks post-operation, with a higher incidence of osteogenesis observed in rat cranial defects eight weeks post-surgery.
CONCLUSION
Overall, the SAL- and CT-loaded coaxial electrospun nanofiber membrane synergistically enhances bone repair and regeneration.
Topics: Osteogenesis; Animals; Nanofibers; Gelatin; Polyesters; Glucosides; Phenols; Phenanthrenes; Humans; Neovascularization, Physiologic; Human Umbilical Vein Endothelial Cells; Mesenchymal Stem Cells; Rats, Sprague-Dawley; Rats; Male; Bone Regeneration; Membranes, Artificial; Coculture Techniques; Drug Liberation; Cell Differentiation
PubMed: 38957181
DOI: 10.2147/IJN.S461141 -
European Journal of Psychotraumatology 2024Comorbidity between posttraumatic stress disorder (PTSD) and borderline personality disorder (BPD) is surrounded by diagnostic controversy and although various...
Comorbidity between posttraumatic stress disorder (PTSD) and borderline personality disorder (BPD) is surrounded by diagnostic controversy and although various effective treatments exist, dropout and nonresponse are high. By estimating the network structure of comorbid PTSD and BPD symptoms, the current study illustrates how the network perspective offers tools to tackle these challenges. The sample comprised of 154 patients with a PTSD diagnosis and BPD symptoms, assessed by clinician-administered interviews. A regularised partial correlation network was estimated using the GLASSO algorithm in R. Central symptoms and bridge symptoms were identified. The reliability and accuracy of network parameters were determined through bootstrapping analyses. PTSD and BPD symptoms largely clustered into separate communities. Intrusive memories, physiological cue reactivity and loss of interest were the most central symptoms, whereas amnesia and suicidal behaviour were least central. Present findings suggest that PTSD and BPD are two distinct, albeit weakly connected disorders. Treatment of the most central symptoms could lead to an overall deactivation of the network, while isolated symptoms would need more specific attention during therapy. Further experimental, longitudinal research is needed to confirm these hypotheses. ClinicalTrials.gov identifier: NCT03833453.
Topics: Humans; Borderline Personality Disorder; Stress Disorders, Post-Traumatic; Female; Adult; Male; Comorbidity; Reproducibility of Results; Middle Aged
PubMed: 38957149
DOI: 10.1080/20008066.2024.2367815 -
Journal of Experimental Zoology. Part... Jul 2024Sleep is a prominent physiological state observed across the animal kingdom. Yet, for some animals, our ability to identify sleep can be masked by behaviors otherwise...
Sleep is a prominent physiological state observed across the animal kingdom. Yet, for some animals, our ability to identify sleep can be masked by behaviors otherwise associated with being awake, such as for some sharks that must swim continuously to push oxygenated seawater over their gills to breathe. We know that sleep in buccal pumping sharks with clear rest/activity cycles, such as draughtsboard sharks (Cephaloscyllium isabellum, Bonnaterre, 1788), manifests as a behavioral shutdown, postural relaxation, reduced responsiveness, and a lowered metabolic rate. However, these features of sleep do not lend themselves well to animals that swim nonstop. In addition to video and accelerometry recordings, we tried to explore the electrophysiological correlates of sleep in draughtsboard sharks using electroencephalography (EEG), electromyography, and electrooculography, while monitoring brain temperature. The seven channels of EEG activity had a surprising level of (apparent) instability when animals were swimming, but also when sleeping. The amount of stable EEG signals was too low for replication within- and across individuals. Eye movements were not measurable, owing to instability of the reference electrode. Based on an established behavioral characterization of sleep in draughtsboard sharks, we offer the original finding that muscle tone was strongest during active wakefulness, lower in quietly awake sharks, and lowest in sleeping sharks. We also offer several critical suggestions on how to improve techniques for characterizing sleep electrophysiology in future studies on elasmobranchs, particularly for those that swim continuously. Ultimately, these approaches will provide important insights into the evolutionary confluence of behaviors typically associated with wakefulness and sleep.
PubMed: 38957102
DOI: 10.1002/jez.2846 -
Journal of Agricultural and Food... Jul 2024Plants withstand pathogen attacks by recruiting beneficial bacteria to the rhizosphere and passing their legacy on to the next generation. However, the underlying...
Plants withstand pathogen attacks by recruiting beneficial bacteria to the rhizosphere and passing their legacy on to the next generation. However, the underlying mechanisms involved in this process remain unclear. In our study, we combined microbiomic and transcriptomic analyses to reveal how the rhizosphere microbiome assembled through multiple generations and defense-related genes expressed in under pathogen attack stress. Our results showed that continuous exposure to the pathogen DC3000 led to improved growth and increased disease resistance in a third generation of mutant . It could be attributed to the enrichment of specific rhizosphere bacteria, such as and . Pathways associated with plant immunity and growth in . , such as MAPK signaling pathways, phytohormone signal transduction, ABC transporter proteins, and flavonoid biosynthesis, were activated under the influence of rhizosphere bacterial communities. Our findings provide a scientific basis for explaining the relationship between beneficial microbes and defense-related gene expression. Understanding microbial communities and the mechanisms involved in plant responses to disease can contribute to better plant management and reduction of pesticide use.
Topics: Arabidopsis; Rhizosphere; Plant Diseases; Pseudomonas syringae; Disease Resistance; Microbiota; Bacteria; Soil Microbiology; Arabidopsis Proteins; Adaptation, Physiological; Plant Roots; Gene Expression Regulation, Plant
PubMed: 38957087
DOI: 10.1021/acs.jafc.4c02200 -
Australian Journal of General Practice Jul 2024Cardiac implantable electronic devices (CIEDs) are a core component in the management of heart rhythm disorders. The complexity of devices, the information gathered and...
BACKGROUND
Cardiac implantable electronic devices (CIEDs) are a core component in the management of heart rhythm disorders. The complexity of devices, the information gathered and therapy delivered by CIEDs continues to advance at pace.
OBJECTIVE
The aim of this paper is to provide an update on advances in CIED technology and how this applies to managing patients with CIEDs in general practice.
DISCUSSION
In recent years, there have been notable advances in CIED technology. These include widespread magnetic resonance imaging compatibility and automated algorithms to assist in the clinical management of patients. There is the ability for clinicians and pacemaker clinics to monitor devices remotely, avoiding in-clinic visits. Options are now available for leadless pacemakers and subcutaneous defibrillators as an alternative to indwelling leads and associated infection and vascular issues. Techniques have been developed to allow leads to capture the native conduction system, providing physiological cardiac activation (conduction system pacing) for treatment and prevention of heart failure.
Topics: Humans; Defibrillators, Implantable; Pacemaker, Artificial; Arrhythmias, Cardiac
PubMed: 38957055
DOI: 10.31128/AJGP-05-23-6847 -
Journal of Cellular and Molecular... Jul 2024This research explores the role of microRNA in senescence of human endothelial progenitor cells (EPCs) induced by replication. Hsa-miR-134-5p was found up-regulated in...
This research explores the role of microRNA in senescence of human endothelial progenitor cells (EPCs) induced by replication. Hsa-miR-134-5p was found up-regulated in senescent EPCs where overexpression improved angiogenic activity. Hsa-miR-134-5p, which targeted transforming growth factor β-activated kinase 1-binding protein 1 (TAB1) gene, down-regulated TAB1 protein, and inhibited phosphorylation of p38 mitogen-activated protein kinase (p38) in hsa-miR-134-5p-overexpressed senescent EPCs. Treatment with siRNA specific to TAB1 (TAB1si) down-regulated TAB1 protein and subsequently inhibited p38 activation in senescent EPCs. Treatment with TAB1si and p38 inhibitor, respectively, showed angiogenic improvement. In parallel, transforming growth factor Beta 1 (TGF-β1) was down-regulated in hsa-miR-134-5p-overexpressed senescent EPCs and addition of TGF-β1 suppressed the angiogenic improvement. Analysis of peripheral blood mononuclear cells (PBMCs) disclosed expression levels of hsa-miR-134-5p altered in adult life, reaching a peak before 65 years, and then falling in advanced age. Calculation of the Framingham risk score showed the score inversely correlates with the hsa-miR-134-5p expression level. In summary, hsa-miR-134-5p is involved in the regulation of senescence-related change of angiogenic activity via TAB1-p38 signalling and via TGF-β1 reduction. Hsa-miR-134-5p has a potential cellular rejuvenation effect in human senescent EPCs. Detection of human PBMC-derived hsa-miR-134-5p predicts cardiovascular risk.
Topics: MicroRNAs; Humans; Endothelial Progenitor Cells; Cellular Senescence; Leukocytes, Mononuclear; Middle Aged; Adaptor Proteins, Signal Transducing; Male; Cardiovascular Diseases; p38 Mitogen-Activated Protein Kinases; Female; Aged; Neovascularization, Physiologic; Transforming Growth Factor beta1; Adult; Risk Factors
PubMed: 38957039
DOI: 10.1111/jcmm.18523 -
Critical Reviews in Clinical Laboratory... Jul 2024RNA methylation is a widespread regulatory mechanism that controls gene expression in physiological processes. In recent years, the mechanisms and functions of RNA... (Review)
Review
RNA methylation is a widespread regulatory mechanism that controls gene expression in physiological processes. In recent years, the mechanisms and functions of RNA methylation under diseased conditions have been increasingly unveiled by RNA sequencing technologies with large scale and high resolution. In this review, the fundamental concept of RNA methylation is introduced, and the common types of transcript methylation and their machineries are described. Then, the regulatory roles of RNA methylation, particularly N6-methyladenosine and 5-methylcytosine, in the vascular lesions of ocular and cardiopulmonary diseases are discussed and compared. The ocular diseases include corneal neovascularization, retinopathy of prematurity, diabetic retinopathy, and pathologic myopia; whereas the cardiopulmonary ailments involve atherosclerosis and pulmonary hypertension. This review hopes to shed light on the common regulatory mechanisms underlying the vascular lesions in these ocular and cardiopulmonary diseases, which may be conducive to developing therapeutic strategies in clinical practice.
PubMed: 38957015
DOI: 10.1080/10408363.2024.2370267