Pre- and Post-alpha Motoneuronal Control of the Soleus H-reflex during Sinusoidal Hip Movements in Human Spinal Cord Injury

The aim of this study was to establish the contribution of hip-mediated sensory feedback to spinal interneuronal circuits during dynamic conditions in people with incomplete spinal cord injury (SCI). Specifically, we investigated the effects of synergistic and antagonistic group I afferents on the soleus H-reflex during imposed sinusoidal hip movements. The soleus H-reflex was conditioned by stimulating the common peroneal nerve (CPN) at short (2, 3, and 4 ms) and long (80, 100, and 120 ms) conditioning test (C-T) intervals to assess the reciprocal and pre-synaptic inhibition of the soleus H-reflex, respectively. The soleus H-reflex was also conditioned by medial gastrocnemius (MG) nerve stimulation at C-T intervals ranging from 4 to 7 ms to assess changes in autogenic Ib inhibition during hip movement. Sinusoidal hip movements were imposed to the right hip joint at 0.2 Hz by the Biodex system while subjects were supine. The effects of sinusoidal hip movement on five leg muscles along with hip, knee, and ankle joint torques were also established during sensorimotor conditioning of the reflex. Phase-dependent modulation of antagonistic and synergistic muscle afferents was present during hip movement, with the reciprocal, pre-synaptic, and Ib inhibition to be significantly reduced during hip extension and reinforced during hip flexion. Reflexive muscle and joint torque responses – induced by the hip movement – were entrained to specific phases of hip movement. This study provides evidence that hip-mediated input acts as a controlling signal of pre- and post-alpha motoneuronal control of the soleus H-reflex. The expression of these spinal interneuronal circuits during imposed sinusoidal hip movements is discussed with respect to motor recovery in humans after SCI

Soleus H-reflex Excitability Changes in Response to Sinusoidal Hip Stretches in the Injured Human Spinal Cord

Imposed static hip stretches substantially modulate the soleus H-reflex in people with an intact or injured spinal cord while stretch of the hip flexors affect the walking pattern in lower vertebrates and humans. The aim of this study was to assess the effects of dynamic hip stretches on the soleus H-reflex in supine spinal cord injured (SCI) subjects. Sinusoidal movements were imposed on the right hip joint at 0.2 Hz by a Biodex system. H-reflexes from the soleus muscle were recorded as the leg moved in flexion or extension. Stimuli were sent only once in every hip movement cycle that each lasted 5 s. Torque responses were recorded at the hip, knee, and ankle joints. A hip phase-dependent soleus H-reflex modulation was present in all subjects. The reflex was facilitated during hip extension and suppressed during hip flexion. There were no significant differences in pre- or post-stimulus soleus background activity between the two conditions. Oscillatory responses were present as the hip was maximally flexed. Sinusoidal hip stretches modulated the soleus H-reflex in a manner similar to that previously observed following static hip stretches. The amount of reflex facilitation depended on the angle of hip extension. Further research is needed on the afferent control of spinal reflex pathways in health and disease in order to better understand the neural control of movement in humans. This will aid in the development of rehabilitation strategies to restore motor function in these patients

Effect of Y substitution on the structural and magnetic properties of Dy1-xYxCo5 compounds

Structural and magnetization studies were carried out on Dy1-xYxCo5 [x = 0, 0.2, 0.4, 0.6, 0.8, 1] compounds which crystallize in the hexagonal CaCu5-type structure. Lattice parameters and unit-cell volume increase with Y concentration. Large thermomagnetic irreversibility between the field-cooled and the zero-field cooled magnetization data has been observed in all the compounds, which has been attributed to the domain wall pinning effect. Temperature dependence of magnetization data shows that except DyCo5 and YCo5, all the compounds show spin reorientation transitions in the range of 5-300 K. The spin reorientation temperature decreases from 266 K for x=0.2 to 100 K for x=0.8. Powder x-ray diffractograms of the magnetically aligned samples show that DyCo5 has planar anisotropy at room temperature whereas all the other compounds possess axial anisotropy. The spin reorientation transition has been attributed to a change in the easy magnetization direction from the ab-plane to the c-axis, as the temperature is increased. The anisotropy field and the first order anisotropy constant are found to be quite high in all the compounds except DyCo5. The magnetic properties have been explained by taking into account the variations in contributions arising from the rare earth and transition metal sublattices.Comment: 12 pages, 7 figure

Evaluation of proteome complexes normalizing osmoregulation in salt stressed Luffa acutangula (L.) Roxb.

Modern-day agriculture is facing the challenge of sustaining global food security. However, the rapid increase in salinity stress among arable areas poses a major threat to crop health and yield. Salinity stress is one of the most common and rapidly spreading stress that has a detrimental effect on the productivity of edible plant family i.e. Cucurbitaceae. The present study endeavors to evaluate the Osmoregulators (anti-oxidants and proteins), that supports the growth of two varieties of Luffa acutangula (L.) Roxb. under salt stress. The 2-3 weeks old saplings were exposed to salt stress (up to 200 mM NaCl) for one week. Post-treatment the osmoregulatory metabolites like Trehalose, Proline & enzymic anti-oxidants like peroxidase (POD), Superoxide dismutase (SOD) and proteins using LC-MS/MS were analyzed. In both the varieties, Trehalose increased with increasing salt concentration, while the level of Proline increased in Variety 1 and decreased in Variety 2. With increasing salt concentrations, the POD activity decreased in both varieties whereas that of SOD levels increased in Variety 2 and decreased in Variety 1. The protein identified by LC-MS/MS and functional annotation analysis employing Uniport database & BlastP algorithm, aided in the detection of differentially expressed proteins in response to salt stress. This was followed by metabolic interaction annotation enrichment analysis by FunRich 3.0 tool, enabling characterization of proteins to be involved in the Calvin cycle, amino acids biosynthesis, carbohydrate and energy metabolism, ROS defence, hormonal biosynthesis and signal transduction. The augmentation of the metabolic activities of the Calvin cycle, biosynthesis of amino acids, carotenoids and peroxisomes, glycolytic pathway and the tricarboxylic acid cycle will conceivably influence the photosynthetic capacity in L. acutangula varieties under salt stress. The upsurge of key enzymes involved in these above described biological processes possibly appears to play an important role in the enhancement of salt tolerance

Dix conseils pour réussir la conception et la mise en œuvre d'un programme d’éducation médicale axée sur les compétences

Background: Globally there is a move to adopt competency-based medical education (CBME) at all levels of the medical training system. Implementation of a complex intervention such as CBME represents a marked paradigm shift involving multiple stakeholders. Methods: This article aims to share tips, based on review of the available literature and the authors’ experiences, that may help educators implementing CBME to more easily navigate this major undertaking and avoid “black ice” pitfalls that educators may encounter. Results: Careful planning prior to, during and post implementation will help programs transition successfully to CBME. Involvement of key stakeholders, such as trainees, teaching faculty, residency training committee members, and the program administrator, prior to and throughout implementation of CBME is critical. Careful and selective choice of key design elements including Entrustable Professional Activities, assessments and appropriate use of direct observation will enhance successful uptake of CBME. Pilot testing may help engage faculty and learners and identify logistical issues that may hinder implementation. Academic advisors, use of curriculum maps, and identifying and leveraging local resources may help facilitate implementation. Planned evaluation of CBME is important to ensure choices made during the design and implementation of CBME result in the desired outcomes. Conclusion: Although the transition to CBME is challenging, successful implementation can be facilitated by careful design and strategic planning.Contexte : Partout dans le monde, on observe une tendance en faveur de l’éducation médicale axée sur les compétences (EMAC) à tous les niveaux du système d’éducation médicale. Une intervention complexe comme l’élaboration d’un programme d’EMAC représente un important changement de paradigme qui nécessite l’implication de plusieurs parties prenantes. Méthode : L’objectif de cet article est de partager des conseils dégagés par les auteurs d’une revue de la littérature et de leur propre expérience afin d’aider les éducateurs à mieux s’orienter dans cette entreprise de taille qu’est la mise en œuvre de l’EMAC et à éviter les écueils. Résultats : Une planification minutieuse avant, pendant et après la transition des programmes vers l’EMAC contribue à garantir son succès. L'implication des principales parties prenantes, telles que les stagiaires, le corps enseignant, les membres du comité du programme de résidence et l'administrateur du programme, avant et pendant la mise en œuvre est essentielle. La sélection attentive des éléments clés, comme les activités professionnelles confiables, les évaluations et l'utilisation appropriée de l'observation directe, favorisera l'adoption de l’EMAC. Des tests pilotes peuvent permettre la participation du corps professoral et des apprenants, et à déceler les problèmes logistiques qui peuvent entraver la mise en œuvre. Les conseillers pédagogiques, le recours à la cartographie des programmes d'études et le repérage et la mobilisation de ressources locales peuvent faciliter la mise en œuvre des programmes d’EMAC. L’évaluation planifiée de ces programmes est importante pour garantir que les choix faits lors de leur conception et mise en œuvre aboutissent aux résultats souhaités. Conclusion : Puisque la transition vers l’EMAC peut comporter de nombreux défis, elle peut néanmoins être opérée avec succès grâce à une conception et une planification stratégique minutieuses

Spleen Tyrosine Kinase (Syk) Regulates Systemic Lupus Erythematosus (SLE) T Cell Signaling

Engagement of the CD3/T cell receptor complex in systemic lupus erythematosus (SLE) T cells involves Syk rather than the zeta-associated protein. Because Syk is being considered as a therapeutic target we asked whether Syk is central to the multiple aberrantly modulated molecules in SLE T cells. Using a gene expression array, we demonstrate that forced expression of Syk in normal T cells reproduces most of the aberrantly expressed molecules whereas silencing of Syk in SLE T cells normalizes the expression of most abnormally expressed molecules. Protein along with gene expression modulation for select molecules was confirmed. Specifically, levels of cytokine IL-21, cell surface receptor CD44, and intracellular molecules PP2A and OAS2 increased following Syk overexpression in normal T cells and decreased after Syk silencing in SLE T cells. Our results demonstrate that levels of Syk affect the expression of a number of enzymes, cytokines and receptors that play a key role in the development of disease pathogenesis in SLE and provide support for therapeutic targeting in SLE patients

Toward a Generalizable Framework of Disturbance Ecology Through Crowdsourced Science

© 2021 Graham, Averill, Bond-Lamberty, Knelman, Krause, Peralta, Shade, Smith, Cheng, Fanin, Freund, Garcia, Gibbons, Van Goethem, Guebila, Kemppinen, Nowicki, Pausas, Reed, Rocca, Sengupta, Sihi, Simonin, Słowiński, Spawn, Sutherland, Tonkin, Wisnoski, Zipper and Contributor Consortium.Disturbances fundamentally alter ecosystem functions, yet predicting their impacts remains a key scientific challenge. While the study of disturbances is ubiquitous across many ecological disciplines, there is no agreed-upon, cross-disciplinary foundation for discussing or quantifying the complexity of disturbances, and no consistent terminology or methodologies exist. This inconsistency presents an increasingly urgent challenge due to accelerating global change and the threat of interacting disturbances that can destabilize ecosystem responses. By harvesting the expertise of an interdisciplinary cohort of contributors spanning 42 institutions across 15 countries, we identified an essential limitation in disturbance ecology: the word ‘disturbance’ is used interchangeably to refer to both the events that cause, and the consequences of, ecological change, despite fundamental distinctions between the two meanings. In response, we developed a generalizable framework of ecosystem disturbances, providing a well-defined lexicon for understanding disturbances across perspectives and scales. The framework results from ideas that resonate across multiple scientific disciplines and provides a baseline standard to compare disturbances across fields. This framework can be supplemented by discipline-specific variables to provide maximum benefit to both inter- and intra-disciplinary research. To support future syntheses and meta-analyses of disturbance research, we also encourage researchers to be explicit in how they define disturbance drivers and impacts, and we recommend minimum reporting standards that are applicable regardless of scale. Finally, we discuss the primary factors we considered when developing a baseline framework and propose four future directions to advance our interdisciplinary understanding of disturbances and their social-ecological impacts: integrating across ecological scales, understanding disturbance interactions, establishing baselines and trajectories, and developing process-based models and ecological forecasting initiatives. Our experience through this process motivates us to encourage the wider scientific community to continue to explore new approaches for leveraging Open Science principles in generating creative and multidisciplinary ideas.This research was supported by the U.S. Department of Energy (DOE), Office of Biological and Environmental Research (BER), as part of Subsurface Biogeochemical Research Program’s Scientific Focus Area (SFA) at the Pacific Northwest National Laboratory (PNNL). PNNL is operated for DOE by Battelle under contract DE-AC06-76RLO 1830

Response to the Novel Corona Virus (COVID-19) Pandemic Across Africa: Successes, Challenges, and Implications for the Future

Background: The COVID-19 pandemic has already claimed considerable lives. There are major concerns in Africa due to existing high prevalence rates for both infectious and non-infectious diseases and limited resources in terms of personnel, beds and equipment. Alongside this, concerns that lockdown and other measures will have on prevention and management of other infectious diseases and non-communicable diseases (NCDs). NCDs are an increasing issue with rising morbidity and mortality rates. The World Health Organization (WHO) warns that a lack of nets and treatment could result in up to 18 million additional cases of malaria and up to 30,000 additional deaths in sub-Saharan Africa. Objective: Document current prevalence and mortality rates from COVID-19 alongside economic and other measures to reduce its spread and impact across Africa. In addition, suggested ways forward among all key stakeholder groups. Our Approach: Contextualise the findings from a wide range of publications including internet-based publications coupled with input from senior-level personnel. Ongoing Activities: Prevalence and mortality rates are currently lower in Africa than among several Western countries and the USA. This could be due to a number of factors including early instigation of lockdown and border closures, the younger age of the population, lack of robust reporting systems and as yet unidentified genetic and other factors. Innovation is accelerating to address concerns with available equipment. There are ongoing steps to address the level of misinformation and its consequences including fines. There are also ongoing initiatives across Africa to start addressing the unintended consequences of COVID-19 activities including lockdown measures and their impact on NCDs including the likely rise in mental health disorders, exacerbated by increasing stigma associated with COVID-19. Strategies include extending prescription lengths, telemedicine and encouraging vaccination. However, these need to be accelerated to prevent increased morbidity and mortality. Conclusion: There are multiple activities across Africa to reduce the spread of COVID-19 and address misinformation, which can have catastrophic consequences, assisted by the WHO and others, which appear to be working in a number of countries. Research is ongoing to clarify the unintended consequences given ongoing concerns to guide future activities. Countries are learning from each other