Early Recovery Phase Research Articles

Enhanced frequency of transcription pre-initiation complexes assembly after exposure to UV irradiation results in increased repair activity and reduced probabilities for mutagenesis.

In addition to being essential for gene expression, transcription is crucial for the maintenance of genome integrity. Here, we undertook a systematic approach, to monitor the assembly kinetics of the pre-initiating RNA Polymerase (Pol) II at promoters at steady state and different stages during recovery from UV irradiation-stress, when pre-initiation and initiation steps have been suggested to be transiently shut down. Taking advantage of the reversible dissociation of pre-initiating Pol II after high salt treatment, we found that de novo recruitment of the available Pol II molecules at active promoters not only persists upon UV at all times tested but occurs significantly faster in the early phase of recovery (2 h) than in unexposed human fibroblasts at the majority of active genes. Our method unveiled groups of genes with significantly different pre-initiation complex (PIC) assembly dynamics after UV that present distinct rates of UV-related mutational signatures in melanoma tumours, providing functional relevance to the importance of keeping transcription initiation active during UV recovery. Our findings uncover novel mechanistic insights further detailing the multilayered transcriptional response to genotoxic stress and link PIC assembly dynamics after exposure to genotoxins with cancer mutational landscapes.

The Effects of Geomagnetic Activities on Acceleration Regions of Radiation Belt Electrons

AbstractSolar wind and magnetospheric processes play important roles in relativistic electron acceleration in the Earth's outer radiation belt. However, how geomagnetic activity affects the acceleration region of relativistic electrons is still not clear. Here we first report the local acceleration regions during the strong storm of 1 June 2013. The first local acceleration region occurs at the lower L shell (L* ∼ 4.0) during the early recovery phase, which is associated with non‐continuous substorm activities. The second local acceleration region occurs at the higher L shell (L* ∼ 5.0) during the late recovery phase, which is associated with continuous substorm activities. To provide a more comprehensive picture, we additionally analyze two storm events with different geomagnetic activities. These events suggest that (a) the strong storm makes it possible for the local acceleration regions to occur at different L shells; (b) the timing, intensity, and duration of substorms during the recovery phase are crucial to the location and dynamics of the local acceleration region. These results can help us further understand the dynamics of relativistic electrons in the Earth's outer radiation belt.

Paradoxical increase in left atrial strains early after Covid-19 infection, a result of comprehensive recovery phase four-chamber strains study.

Cardiac consequences of Covid-19 infection have been mentioned in various studies as a serious risk factor for in-hospital mortality. However, the existence of residual cardiac dysfunction after the acute phase is seldom investigated especially in people without a history of specific medical disease.One hundred health care workers with positive reverse transcription-polymerase chain reaction test underwent comprehensive 2D and 3D echocardiography six to eight weeks after infection. Patients were classified into Mild, Moderate, and Severe groups based on their clinical characteristics of covid-19 infection, and all echocardiographic parameters were compared between the three groups. Left ventricular (LV) stroke volume index was reduced in all groups compared to normal ranges and was more prominent in the severe group (P-value < 0.05). 3D-derived LV global longitudinal strain (GLS) was significantly lower in the severe group in comparison to the mild group (- 19.3 ± 1 Vs. - 22.2 ± 2, P-value < 0.001) and correlated with highly sensitive CRP level at the acute phase. Left atrial (LA) strains, including LA peak strain, LA contraction strain, and LA reservoir strain, were considerably higher and LA volume index was significantly lower in the clinically severe covid patients. Analysis based on the extent of lung involvement showed significantly increased 3D-derived right ventricular volumes in patients who experienced severe pneumonia despite normalized strains. Conclusion: subclinical LV dysfunction as reduced stroke volume index and GLS exists in the early recovery phase of normal individuals with severe course of covid-19. LA function indicated by LA strains paradoxically increases in severe covid-19 infection in this phase.

Statistical Study of the Ionospheric Slab Thickness at Beijing Midlatitude Station

The ratio of the total electron content (TEC) to the F2-layer peak electron density (NmF2) is known as the ionospheric equivalent slab thickness (EST, also known as τ), and it is a crucial indicator of the ionosphere. Using TEC and NmF2 data from the years 2010 to 2017, this work conducts a comprehensive statistical analysis of the ionospheric slab thickness in Beijing, which is in the midlatitude of East Asia. The outcomes show that the τ have different diurnal variations at different seasons for high/low-solar-activity years. On the whole, daytime τ significantly greater than nighttime τ in summer, and it is the opposite for the τ in winter regardless of the solar cycle, whereas the τ during equinox shows different morphology for high/low-solar-activity years. Specifically, daytime τ is larger than nighttime τ during equinox in years of high-solar activity, while the opposite situation applies for the τ during equinox in years of low-solar activity. Moreover, the pre-sunrise and post-sunset peaks are most pronounced during winter for low-solar-activity years. In summer, there is a great increase in τ during the morning hours when compared with other seasons. Furthermore, the τ decreases with the solar activity during nighttime, whereas it seems there is no correlation between daytime τ and solar activity. This paper explained the primary diurnal variations in τ across different seasons during high-/low-solar-activity years by analyzing relative fluctuations of TEC and NmF2 throughout the corresponding period. In addition, based on the disturbance index (DI), which is calculated by instantaneous τ and its corresponding median, this paper found that the storm-time τ might increase when compared with its median value during the daytime, while it may both increase and decrease during the nighttime, especially around dawn and dusk hours. To further analyze the physical mechanism, an example on 2 October 2013 is also presented. The results indicate that the positive disturbance of τ during the main phase of a geomagnetic storm might be caused by the prompt penetration electric field and neutral wind during the storm, and the τ increases during the early recovery phase might be due to the disturbance dynamo electric field as well as the neutral wind during the storm. Moreover, there is a negative disturbance of τ in the recovery phase during the most disturbed sunrise hours, and it might be due to the electric field reversal, neutral wind or other factors during this period. This paper notes the differences of τ in midlatitude between different longitudinal sectors from the related climatology and storm-time behavior, as it would be helpful to improve the current understanding of τ at midlatitudes in East Asia.

Magnetic Resonance Imaging of Cardiovascular Manifestations Following COVID-19.

Globally, over 650 million people have had COVID-19 due to infection with the SARS-Cov-2 virus. Cardiac complications in the acute infectious and early recovery phase were recognized early in the pandemic, including myocardial injury and inflammation. With a decrease in the number of acute COVID-19 related deaths, there has been increased interest in postacute sequela of COVID-19 (PASC) and other longer-term cardiovascular complications. A proportion of patients recovered from COVID-19 have persistent cardiac symptoms and are at risk of cardiovascular disease. Cardiovascular imaging, including MRI, plays an important role in the detection of cardiovascular manifestations of COVID-19 in both the acute and longer-term phases after COVID-19. The purpose of this review is to highlight the role of cardiovascular imaging in the diagnosis and risk stratification of patients with acute and chronic cardiovascular manifestations of COVID-19 with a focus on cardiac MRI. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: Stage 3.

Enhanced Splanchnic Extraction Of Nutritional Arginine And Lower Citrulline Production Play A Role In The Reduced Systemic Availability Of Arginine In The Early Recovery Phase Of Sepsis In The Pig

Enhanced Splanchnic Extraction Of Nutritional Arginine And Lower Citrulline Production Play A Role In The Reduced Systemic Availability Of Arginine In The Early Recovery Phase Of Sepsis In The Pig

From the Inner Circle to Rebuilding Social Networks: A Grounded Theory Longitudinal Study Exploring the Experience of Close Personal Relationships from the Perspective of People with Post Stroke Aphasia

ABSTRACT Background Interpersonal relationships are frequently subject to challenges and changes following the onset of aphasia and have strong ties with psychosocial and health outcomes. In order to be able to effectively support people with aphasia, a greater understanding of how challenges and changes evolve over time is needed. Aims The current research sought to understand the lived experience of interpersonal relationships for people with aphasia through longitudinal enquiry over the first year following the onset of stroke. Methods and Procedures Seven participants with aphasia (6 male, 1 female) with aphasia ranging from mild to severe were recruited through inpatient rehabilitation units. Four were married and three lived alone. They were interviewed on four occasions beginning around the time of their discharge home and lasting for around one year following their return home. Researchers adopted a constructivist grounded theory approach and data were transcribed, coded and analysed using a constant comparative method. Outcomes and Results This research provides novel insights into the progression of interpersonal relationships over time following the onset of aphasia. Early on, participants retreated into a core group of close others characterised as their ‘inner circle’. During early stages, inner circle relationships were subject to challenges and changes as people learned to live with aphasia. As they felt ready, people with aphasia began to reconnect with friends. This process was often mediated by spouses and in the early phases of recovery was limited and challenging. Reconnection with friends brought with it varying degrees of connectedness, however for those without strong inner circle relationships, marked isolation occurred at all points throughout the year following discharge. Conclusions Relationships are frequently impacted by the presence of aphasia and are subject to changes and challenges. This research highlights phases which people with aphasia may move through as they adjust to their new social worlds. These findings have clear implications for the development and timing of interventions and emphasise the need to support those most at risk.

Aquatic vegetation types identified during early and late phases of vegetation recovery in the Upper Mississippi River

AbstractAssemblage patterns and processes of aquatic vegetation in most large floodplain rivers are not well understood, particularly after plant recovery. Identifying vegetation types, which are recurring plant groupings based on species composition, diversity, and abundances, can describe plant assembly patterns and environmental drivers that aid conservation planning and management. We used a 22‐year dataset (n = 18,000 sampling plots) to identify aquatic vegetation types during an “early phase” and “late phase” of plant recovery at multiple spatial scales nested within a 500‐km river reach of the Upper Mississippi River, USA. We hypothesized that vegetation types varied according to scale because of the stark environmental differences among riverine habitats and differing regional species pools along the river's latitudinal gradient, and that the late phase of recovery had developed several new vegetation types. We first used cluster analyses at multiple spatiotemporal scales to identify the number of vegetation types and their characteristics, such as indicator species, species compositions and abundances, and diversity index. Then we applied a multivariate regression to pinpoint environmental factors (such as hydrodynamics, system productivity, local habitat, and water quality) that structured those vegetation types. Clustering revealed that ~90% of plots irrespective of recovery phase were not classified into vegetation types, which indicated that most aquatic sampling plots are unique in species composition and unpredictable. However, impounded areas upriver from dams had matured five vegetation types: lotus (Nelumbo lutea Willd.), submersed (a mix of 11 common submersed species), watercelery (Vallisneria americana Michx.), arrowheads (Sagittaria rigida Pursh and Sagittaria latifolia Willd.), and a diverse community (with high diversity indices and multiple life forms). The vegetation types were associated with three environmental gradients related to inundation depth and duration, system productivity, and water clarity. These five vegetation types are known to be of high ecological value to fish and wildlife and thus targets for restoration, for example, the watercelery community is principal forage for migrating canvasback ducks (Aythya valisineria) along the Mississippi River flyway. Our results provide insights on vegetation assembly during recovery and aid habitat conservation by providing quantitative, environmental targets for restoration.

Effect of Dexmedetomidine on Incidence of Emergence Delirium in Adult Nasal Surgery

Background/Purpose/Question. Emergence delirium (ED) is an acute phenomenon that develops in the early phase of recovery from general anesthesia, and characterized by confusion, disorientation, &amp; possible violent behavior, and is a common occurrence particularly with nasal surgery. Dexmedetomidine is a highly selective alpha-2 adrenergic agonist that results in anxiolysis, sedation, analgesia, and sympatholysis without depressing ventilation. This educational scholarly project aimed to review the literature and investigate the effect of intraoperative dexmedetomidine on the incidence of ED in adults recovering from general anesthesia after nasal surgery. Methods/Evidence Search. PubMed and EMBASE were structurally searched from 2011 to 2021. Five randomized controlled studies (RCT) were selected that compared intraoperative dexmedetomidine to a placebo and how the recovery profile was affected in adults after nasal surgery. Key search terms included “anesthesia”, “dexmedetomidine”, “emergence”, “nasal surgery”. Synthesis of Literature/Results/Discussion. There were collectively 392 participants across these five studies, and the incidence of ED in dexmedetomidine groups was significantly lower than control groups (respectively 21% vs. 50%). The mean arterial pressure (MAP) and heart rate (HR) among dexmedetomidine groups exhibited less variability during emergence without hypotension, which indicates a more stable hemodynamic profile. Analgesic and antiemetic requirements in the post-anesthesia care unit (PACU) were decreased in dexmedetomidine groups, however these results were not statistically significant. Conclusion/Recommendations for Practice. Intraoperative dexmedetomidine significantly decreases the incidence of ED. Secondary effects, like hemodynamic stability and analgesia, were observed, but these qualities need to be further studied before they can be generalized. Overall, dexmedetomidine is a safe and effective anesthetic adjunct that facilitates a smoother emergence after nasal surgery without any complications. Keywords: Anesthesia, dexmedetomidine, emergence, nasal surgery

Psychological First Aid principles within a community-led arts initiative: lessons from the Blacksmiths' Tree.

Psychological First Aid (PFA) is widely used in the early phases of disaster recovery, despite limited empirical evidence supporting its application. PFA aims to reduce distress and encourage adaptive coping and is grounded in five principles: the promotion of hope, self- and collective efficacy, social connectedness, safety, and calm. Drawing on a constructivist perspective, this study analysed interview transcripts from Forged from Fire: The Making of the Blacksmiths' Tree, a documentary film about a community-led arts project initiated after the 2009 bushfires in Victoria, Australia. Using a reflexive process that employed deductive and inductive coding, the research investigated the presence of PFA principles in participants' experiences of the Blacksmiths' Tree project and whether themes not accounted for by PFA were also salient. The findings supported the PFA principles and generated two additional themes: grassroots and community leadership; and healing through creation and expression. The implications for disaster recovery in community settings are also presented.

Abstract WMP30: Expansion Of Plasma Micrornas Over The First Month Following Human Stroke

Introduction: Stroke induces changes in plasma microRNA (miRNA) expression in the first 24hrs post-injury, but few have characterized miRNA expression during the early recovery phase. Hypothesis: We hypothesized that plasma miRNA expression would evolve over the first month post-stroke with fewer significantly altered miRNAs over time as inflammation and edema resolve. Methods: Longitudinal samples were collected 5, 15, and 30 days post-stroke from 2 studies (BIOREC and MORSE, n=55 combined at each time point) and compared to controls matched for age, sex, race and cardiovascular comorbidities. Stroke samples collected on average around day 15 from a second study (CPASS, n=48) were also compared to matched controls and used as a validation cohort. MiRNA expression was determined with OpenArray qRT-PCR quantifying 758 miRNAs. Significant miRNAs had a corrected p-value less than 0.05 and fold-change greater than |1.5|. Results: Eight miRNAs remained significantly altered across all 3 time points in the discovery cohort and in the day 15 validation cohort (decreased expression compared to controls: miR-101-3p, miR-107, miR-16-2-3p, miR-19a-3p, miR-19b-3p, and miR-26b-5p; increased expression: miRNA-199a-3p and miR-652-3p). The number of significant miRNAs more than doubled from post-stroke day 5 to days 15 and 30 (19, 53, and 45 miRNAs respectively in BIOREC/MORSE, 49 miRNAs at day 15 in CPASS). At day 5 most significant miRNAs (14/19) showed decreased expression compared to controls whereas by day 30 most demonstrated increased expression (36/45). Many of the significant miRNAs, including miR-107 and miR-652-3p, and many others at days 15 and 30 were enriched in brain or CSF in prior studies. Conclusions: While several miRNAs show significant change in expression consistently from 5 to 30 days post-stroke, there is also an expansion of significant miRNAs at days 15 and 30. This expansion includes many miRNAs enriched in brain or CSF and could represent a shift from inflammation to neural repair processes, but this requires further study.

Alpha-adrenergic receptor activation after fetal hypoxia-ischaemia suppresses transient epileptiform activity and limits loss of oligodendrocytes and hippocampal neurons

Exposure to hypoxic-ischaemia (HI) is consistently followed by a delayed fall in cerebral perfusion. In preterm fetal sheep this is associated with impaired cerebral oxygenation, consistent with mismatch between perfusion and metabolism. In the present study we tested the hypothesis that alpha-adrenergic inhibition after HI would improve cerebral perfusion, and so attenuate mismatch and reduce neural injury. Chronically instrumented preterm (0.7 gestation) fetal sheep received sham-HI (n = 10) or HI induced by complete umbilical cord occlusion for 25 minutes. From 15 minutes to 8 hours after HI, fetuses received either an intravenous infusion of a non-selective alpha-adrenergic antagonist, phentolamine (10 mg bolus, 10 mg/h infusion, n = 10), or saline (n = 10). Fetal brains were processed for histology 72 hours post-HI. Phentolamine infusion was associated with increased epileptiform transient activity and a greater fall in cerebral oxygenation in the early post-HI recovery phase. Histologically, phentolamine was associated with greater loss of oligodendrocytes and hippocampal neurons. In summary, contrary to our hypothesis, alpha-adrenergic inhibition increased epileptiform transient activity with an exaggerated fall in cerebral oxygenation, and increased neural injury, suggesting that alpha-adrenergic receptor activation after HI is an important endogenous neuroprotective mechanism.

First Observations of Equatorial Ionospheric Electric Fields Driven by Storm‐Time Rapidly Recurrent Magnetospheric Substorms

AbstractGeomagnetic storm ionospheric electrodynamics at the magnetic equator are examined in detail using upgraded, higher time resolution, Jicamarca incoherent scatter radar drift observations, SuperMAG geomagnetic field, and solar wind data to study equatorial ionospheric electric fields during the 8 September 2017 storm main and early recovery phases. We show that during a period of mostly large and southward Interplanetary Magnetic Field (IMF) Bz there were numerous daytime prompt penetration vertical and zonal plasma drifts. These prompt penetration events were closely associated with rapidly recurring (quasi‐periods ∼30 − 60 min) magnetospheric substorms with expansion phases corresponding to upward and westward drift (eastward and downward electric field) perturbations, and recovery phases to opposite polarity changes. The magnitudes of the zonal prompt penetration drifts were about twice larger than those of the vertical drifts. Our study suggests that magnetospheric substorms are the main drivers of prompt penetration electric fields during extended periods (over ∼2 hr) of nearly steady southward IMF Bz. We also find that in general substorms are major driving factors for disturbance electric fields during geomagnetic active times. Our data highlight the powerful capabilities of the Jicamarca incoherent scatter radar as a tool for detailed studies of short‐lived solar wind‐magnetosphere‐ionosphere coupling processes.

Understanding the impacts of floods on learning quality, school facilities, and educational recovery in Indonesia.

This research is among the first pieces of work to use the comprehensive school safety (CSS) framework to assess the impacts of floods on quality learning and education infrastructure. The CSS framework is employed here to identify the level of disruption to education services following floods in Jakarta, Indonesia, in 2013. The paper poses three key questions, concerning: (i) disruption to children's access to quality education during the flood emergency in 2013 and the early recovery phase; (ii) the impact of the floods on a school's physical infrastructure; and (iii) the effectiveness and level of success of the 2013 flood responses by relevant stakeholders. Combining quantitative and qualitative strategies, the paper examines the experiences of 100 schools in Jakarta. The findings suggest that the CSS framework offers a more nuanced approach to assessing post-disaster education needs. Moreover, it is also relevant for examining the relationship between the COVID-19 pandemic and relative losses in the education sector.

A Tailored Occupational Therapist-Led Vocational Intervention for People With Stroke: Protocol for a Pilot Randomized Controlled Trial.

Resuming work after stroke is a common goal of working-age adults, yet there are few vocational rehabilitation programs designed to address the unique challenges faced following stroke. The Work intervention was developed to address these gaps. This paper presents a protocol that outlines the steps that will be undertaken to pilot both the intervention and trial processes for the Work trial. The Work trial is a 2-arm, prospective, randomized, blinded-assessor study with intention-to-treat analysis. A total of 54 adults of working age who have experienced a stroke <4 months prior will be randomized 1:1 to either (1) an experimental group who will receive a 12-week early vocational intervention (Work intervention) plus usual clinical rehabilitation or (2) a control group who will receive only their usual clinical rehabilitation. Outcomes include study and intervention feasibility and intervention benefit. In addition to evaluating the feasibility of delivering vocational intervention early after stroke, benefit will be assessed by measuring rates of vocational participation and quality-of-life improvements at the 3- and 6-month follow-ups. Process evaluation using data collected during the study, as well as postintervention individual interviews with participants and surveys with trial therapists, will complement quantitative data. The results of the trial will provide details on the feasibility of delivering the Work intervention embedded within the clinical rehabilitation context and inform future trial processes. Pilot data will enable a future definitive trial to determine the clinical effectiveness of vocational rehabilitation when delivered in the early subacute phase of stroke recovery. Australian New Zealand Clinical Trials Registry ACTRN12619001164189; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378112&isReview=true. DERR1-10.2196/40548.

Clinical and prognostic relevance of sST2 in adults with dengue-associated cardiac impairment and severe dengue.

Dengue can be complicated by severe outcomes including cardiac impairment, and the lack of reliable prognostic biomarkers poses a challenge in managing febrile dengue patients. Here, we investigated the functionality of soluble suppressor of tumorigenicity (sST2) as a predictive marker of severe dengue and its association in dengue-associated cardiac impairment. Plasma samples, aged >16 years, collected from 36 dengue fever, 43 dengue with warning signs, 11 severe dengue (collected at febrile, critical and recovery phases) and 30 controls were assayed for plasma levels of sST2, troponin T and N-terminal (NT)-pro hormone brain natriuretic peptide (NT-proBNP) by ELISA. Cardiac parameters: stroke index (SI), cardiac index (CI) and Granov-Goor Index (GGI) were measured with a bioimpedance device during the different phases for dengue subjects and once for the controls. In the febrile, critical and early recovery phases, sST2 levels were significantly elevated in dengue participants and sST2 levels increased with increasing disease severity (P < 0.01 for all). sST2 concentrations were negatively correlated with SI (r = -0.48; P < 0.001, r = -0.55; P < 0.001), CI (r = -0.26; P = 0.02, r = -0.6: P < 0.001) and GGI (r = -0.44; P < 0.001, r = -0.57; P < 0.001) in the critical and early recovery phases. In contrast, sST2 levels in the febrile and critical phases, were positive correlated to troponin T (r = 0.44, P < 0.001; r = 0.22, P = 0.03, respectively) and NT-proBNP (r = 0.21, P = 0.03; r = 0.35, P < 0.001). ROC analysis demonstrated sST2 as a good biomarker of severe dengue in the critical phase, AUROC 0.79, P < 0.001. sST2 levels were elevated in patients with dengue especially in cases of severe dengue. Furthermore, increased sST2 levels were associated with cardiac indicators suggesting lower cardiac performance. While further research is needed to demonstrate its clinical utility, sST2 may be a useful prognostic biomarker of severe dengue.

Exercise-induced ventricular arrythmia in asymptomatic patients with Mitral Valve Prolapse

Abstract Introduction Mitral Valve Prolapse (MVP) is associated with complex ventricular arrythmia (VA) and sudden cardiac death but risk stratification remains unclear. Exercise induces an hyperadrenergic state and could trigger VA, however, data on exercise-induced VA (EIVA) in MVP patients are scarce. Objective To describe EIVA prevalence, origin, characteristics and associated features in MVP patients. Methods In this observational prospective study, 64 MVP asymptomatic patients (58±14 years, 41 men) with mild to severe mitral regurgitation (MR) and without left ventricular (LV) dysfunction, underwent echocardiography and symptom-limited exercise testing. Continuous 12-lead ECG monitoring was performed throughout testing. Severe EIVA was defined as ventricular triplets, sustained or non-sustained ventricular tachycardia (NSVT) or ventricular fibrillation. Results All patients exercised at maximal intensity until exhaustion. EIVA was observed in 54 (84%) subjects including 12 (19%) patients with severe EIVA (7 triplets, 5 NSVT). Severe EIVA originated mainly from the mitral apparatus (all but one) and occurred at high exercise intensity (median 90% of predicted workload) or during early recovery phase. Compared to the rest of the cohort the patients with severe EIVA had similar resting ECG characteristics, similar LV dimension and function, similar degree of MR and mitral apparatus morphology. Finally, severe EIVA was not associated with an alteration of exercise tolerance. Conclusion Exercise frequently unmasks ventricular arrythmia in patients with MVP. EIVA appears not linked to MVP features nor to exercise tolerance and seems to provide additional phenotyping information that could be linked to prognosis. Funding Acknowledgement Type of funding sources: None.

Difference in muscle synergies of the butterfly technique with and without swimmer’s shoulder

This study aimed to investigate whether muscle synergy differs between swimmers with and without swimmer's shoulder in the butterfly technique. Muscle synergies, which can assess muscle coordination, were analyzed using surface electromyography. Twenty elite swimmers were included in this study (swimmer's shoulder: n = 8; control: n = 12). The motions involved in executing the butterfly technique were classified into the early pull-through, late pull-through, and recovery phases. Muscle synergy data analyzed using the nonnegative matrix factorization method were compared between the two groups.The swimming velocities were 1.66 ± 0.09 m・s −1 and 1.69 ± 0.06 m・s −1 for the control and swimmer's shoulder groups, respectively. Four muscle synergies in both groups were identified: synergy #1, which was involved in the early pull; synergy #2, involved in the late pull; synergy #3, involved in the early recovery; and synergy #4, involved in pre- and posthand entry. Compared to the control group, the swimmer's shoulder group had a small contribution from the pectoralis major (p = 0.032) and a high contribution from the rectus femoris during the early pull phase (p = 0.036). In the late pull phase, the contribution of the lower trapezius muscle in the swimmer's shoulder group was low (p = 0.033), while the contribution of the upper trapezius muscle in the pre- and postentry phases was high (p = 0.032). In the rehabilitation of athletes with swimmer's shoulder, it is therefore important to introduce targeted muscle rehabilitation in each phase.

Effects Of Eccentric-overload Strenght Training In The Sub-acute Recovery Phase After A Stroke

Eccentric-overload strength training improves neuromuscular function and physical performance in healthy adults. Recent studies have shown its benefits in certain medical conditions, like chronic stroke patients, where they found improvements in strength related to better functional performance, gait or cognition parameters. However, the effects of an eccentric-overload training program during the stroke sub-acute rehabilitation phase remain unclear. PURPOSE: To determine the effects of eccentric-overload strength training during the sub-acute phase after stroke on strength, activities of daily living (ADL) and quality of life. METHODS: Six participants (5 men and 1 woman) with sub-acute stroke (3.92 month after the event, ±2.06), aged 44 (±9.98), with hemiparesis (4 subjects with left hemiparesis and 2 with right), performed an 8 training session program using an inertial conical pulley. Every session included upper and lower limb strength exercises. Each participant performed 2 series of 10 repetitions for every exercise and did it at the 70% of their maximal strength (indirectly estimated by a computer program to assess motor actions). Participants were assessed before and after the training period. Strength was measured using a computer program for motor actions and the pulley. Functional performance in ADL was assessed using the Barthel Index (BI) and quality of life was assessed with the short version of the World Health Organization Quality of Life Questionnaire (WHOQOL-BREF). Descriptive data for all variables were obtained. To compare pre and post intervention, a paired Wilcoxon test was applied, and correlation between strength, BI and WHOQOL-BREF were studied through Spearman’s correlation rank. RESULTS: BI improved significantly (p = 0.031), left hip flexion muscles and left shoulder’s also showed significant improvements (p = 0.031 and p = 0.059 respectively) after the intervention. No relationship between strength and questionnaires were found. CONCLUSION: An overload-eccentric training program added to a regular rehabilitation program in an early recovery phase after stroke showed significant positive effects in the BI and strength of the affected side. No correlations were found between variables. More research is needed.

Macrophage immunomodulation accelerates skeletal muscle functional recovery in aged mice following disuse atrophy.

Poor recovery of muscle size and strength with aging coincides with a dysregulated macrophage response during the early stages of regrowth. Immunomodulation in the form of ex vivo cytokine (macrophage-colony stimulating factor) or polarized macrophage delivery has been demonstrated to improve skeletal muscle regeneration. However, it is unclear if these macrophage-promoting approaches would be effective to improve skeletal muscle recovery following disuse in aged animals. Here, we isolated bone marrow-derived macrophages from donor mice of different ages under various experimental conditions and polarized them into proinflammatory macrophages. Macrophages were delivered intramuscularly into young adult or aged recipient mice during the early recovery period following a period of hindlimb unloading (HU). Delivery of proinflammatory macrophages from donor young adults or aged mice was sufficient to increase muscle function of aged mice during the recovery period. Moreover, proinflammatory macrophages derived from aged donor mice collected during recovery were similarly able to increase muscle function of aged mice following disuse. In addition to the delivery of macrophages, we showed that the intramuscular injection of the cytokine, macrophage-colony stimulating factor, to the muscle of aged mice following HU was able to increase muscle macrophage content and muscle force production during recovery. Together, these results suggest that macrophage immunomodulation approaches in the form of ex vivo proinflammatory macrophage or macrophage-colony stimulating factor delivery during the early recovery phase following disuse atrophy were sufficient to restore the loss of aged skeletal muscle function.NEW & NOTEWORTHY A single intramuscular administration of polarized macrophages into muscles of aged mice following a bout of disuse atrophy was sufficient to improve functional recover similarly to young adults after disuse atrophy regardless of the age or experimental condition of the donor mice. Additionally, intramuscular delivery of macrophage-colony stimulating factor into aged mice was similarly effective. Targeting macrophage function early during the regrowth phase may be a novel tool to bolster muscle recovery in aging.