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PURPOSE: This narrative review evaluated the impact of exercise on gait and cognitive functions in patients with Parkinson's disease (PD), focusing on prefrontal cortical (PFC) activation assessed using near-infrared spectroscopy (NIRS). METHODS: A literature search was conducted in the PubMed and Web of Science databases using keywords such as "Parkinson's disease," "gait," "cognitive functions," "exercise," and "NIRS," focusing on publications from the last decade. Studies measuring PFC activity using NIRS during gait tasks in patients with PD were selected. RESULTS: The review indicated that patients with PD demonstrate increased PFC activity during gait tasks compared to healthy controls, suggesting a greater cognitive demand for movement control. Exercise has been shown to enhance neural efficiency, thus improving gait and cognitive functions. CONCLUSION: Exercise is crucial for improving gait and cognitive functions in patients with PD through increased PFC activation. This emphasizes the importance of incorporating exercise into PD management plans and highlights the need for further studies on its long-term effects and the neurobiological mechanisms underlying its benefits, with the aim of optimizing therapeutic strategies and improving patients' quality of life.
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Marker-based 3D motion capture systems, widely used for gait analysis, are accurate but have disadvantages such as cost and accessibility. Whereas markerless pose estimation has emerged as a convenient and cost-effective alternative for gait analysis, challenges remain in achieving optimal accuracy. Given the limited research on the effects of camera location and orientation on data collection accuracy, this study investigates how camera placement affects gait assessment accuracy utilizing five smartphones. This study aimed to explore the differences in data collection accuracy between marker-based systems and pose estimation, as well as to assess the impact of camera location and orientation on accuracy in pose estimation. The results showed that the differences in joint angles between pose estimation and marker-based systems are below 5°, an acceptable level for gait analysis, with a strong correlation between the two datasets supporting the effectiveness of pose estimation in gait analysis. In addition, hip and knee angles were accurately measured at the front diagonal of the subject and ankle angle at the lateral side. This research highlights the significance of careful camera placement for reliable gait analysis using pose estimation, serving as a concise reference to guide future efforts in enhancing the quantitative accuracy of gait analysis.
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OBJECTIVE: To determine whether physical exercise interventions can improve cognitive function, including overall performance and specific domains, in patients with Parkinson's disease (PD) and to provide potential evidence on how cognitive benefits can be optimized by exercise prescriptions. METHODS: Using PubMed, Web of Science, and Cochrane Library (from inception to August 2022), four independent reviewers screened the search results and extracted data from randomized controlled trials of physical exercise interventions in patients with PD with an outcome measure of cognitive function. Random-effects meta-analysis models were used to report standardized mean differences (SMDs) with 95 % confidence intervals (CIs). RESULTS: Twenty-one randomized controlled trials including 761 patients with PD were eligible for inclusion. Physical exercise interventions led to significant improvements in global cognitive function (SMD = 0.69; 95 % CI = 0.31 to 1.06; P < 0.001). With respect to cognitive domains, the significant effect of exercise was found on executive function (SMD = 0.94; 95 % CI = 0.05 to 1.83; P = 0.039), but not on attention/working memory, language, memory, and visuospatial function. In moderator variable analyses, the effect on global cognition was observed in combined exercise programs (SMD = 0.79; 95 % CI = 0.46 to 1.12; P < 0.001), whereas there were no significant positive effects in aerobic exercise programs, strength exercise programs, and flexibility exercise programs. In addition, exercise interventions of light-to-moderate intensity with at least 60 min in duration, and of any frequency or period, were beneficial to the global cognitive function. CONCLUSION: This updated systematic review and meta-analysis suggests that physical exercise interventions are effective in improving global cognitive function and, to a lesser extent, executive function in patients with PD. At least 60 min a day of combined exercise programs on as many days of the week as feasible may be recommended as the non-pharmacological therapeutic option to improve cognitive function.
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Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto , Cognición , Ejercicio Físico , Terapia por EjercicioRESUMEN
OBJECTIVE: Although orthostatic hypotension (OH) and orthostatic intolerance (OI) are prevalent in patients with Parkinson disease (PD), it remains unclear how these conditions primarily affect the trajectory of decline in specific cognitive domains. This study aimed to explore the effects of OH and OI on longitudinal domain-specific cognitive changes in patients with PD. DESIGN: An 8-year follow-up of the Parkinson Progression Markers Initiative cohort study. SETTING AND PARTICIPANTS: A total of 403 patients with early, untreated PD and 195 matched healthy controls were included. They were classified into OH, OI, and normal groups. OH was defined according to the international consensus, and OI was defined as the presence of orthostatic symptoms without meeting the criteria for OH. METHODS: The patients underwent detailed neuropsychological testing annually for up to 8 years of follow-up. Linear mixed effects models were used to investigate the associations between OH, OI, and longitudinal cognitive changes. RESULTS: The prevalence of both OH and OI in patients with PD was significantly higher than that in controls (13.4% vs 7.2%, P = .002, for OH, and 29.3% vs 14.4%, P < .001, for OI). The OH group in patients with PD showed a faster decline in Letter-Number Sequencing (LNS) (ß = -0.11, 95% CI -0.20 to -0.02, t = -2.44, P = .015) and Semantic Fluency Test (SFT) (ß = -0.44, 95% CI -0.81 to -0.08, t = -2.42, P = .016) scores than the normal group. Similarly, the OI group showed a steeper decline in LNS (ß = -0.08, 95% CI -0.14 to -0.01, t = -2.20, P = .028) and SFT (ß = -0.36, 95% CI -0.63 to -0.08, t = -2.55, P = .011) scores compared to the normal group. There were no significant longitudinal changes in the other neuropsychological test scores between the groups. CONCLUSIONS AND IMPLICATIONS: Both OH and OI may be associated with a faster decline in executive function among cognitive domains of patients with PD. These findings may highlight the potential importance of orthostatic blood pressure control in PD patients with OH and even those with orthostatic symptoms without OH.
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OBJECTIVE: To evaluate the potential efficacy of two different supervised exercise regimens, namely high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT), on sarcopenia-related parameters in participants with Parkinson's disease (PD). METHODS: We analyzed data from a randomized controlled pilot trial (CRIS identifier: KCT0007130). An aerobic exercise intervention using a cycle ergometer (40-60 min) in combination with calisthenics (5 min) was performed in three sessions/week for 24 weeks for HIIT (60% maximum aerobic power for 30-50 s with 1-min rest intervals) and MICT (50% peak oxygen consumption) groups. Changes in sarcopenia-related parameters, including appendicular skeletal muscle mass (ASM), ASM index (ASM/height2), handgrip strength, 6-min walking distance, and 30-s chair-stand test (30CST) score, were compared among the HIIT (n = 9), MICT (n = 10), and usual care (n = 11) groups. RESULTS: The HIIT group showed greater increases in leg lean mass (p = 0.011), ASM (p = 0.035), and ASM index (p = 0.025), and greater improvements in 6-min walking distance (p = 0.024) and 30CST scores (p = 0.026) compared with the usual care group. However, among these parameters, only the 30CST score significantly improved in the MICT group compared to the usual care group (p = 0.002). Three of the four (75%) sarcopenic patients who underwent HIIT showed improved sarcopenia after the 24-week exercise intervention, whereas it did not improve in the sarcopenic patients included in the MICT (n = 2) and usual care (n = 2) groups. CONCLUSION: This study suggests that HIIT may be superior to MICT in improving sarcopenia in patients with PD. Further large-scale investigations are required to confirm our findings.
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Entrenamiento de Intervalos de Alta Intensidad , Enfermedad de Parkinson , Sarcopenia , Humanos , Sarcopenia/etiología , Sarcopenia/terapia , Proyectos Piloto , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/terapia , Fuerza de la ManoRESUMEN
Chronic myelogenous leukemia (CML) is a hematologic malignancy with unique significance to the field of hematology and oncology, specifically due to the development of tyrosine kinase inhibitors (TKIs). CML often presents with nonspecific symptoms, and the quality of life in patients with CML has drastically improved as a result of TKIs. However, complications of CML including the risk of transforming into life-threatening blast crises continue to exist. Further, as most patients are asymptomatic in the chronic phase, patients often present with serious complications associated with noncompliance to TKIs. For example, central nervous system (CNS) manifestations of CML have been reported, both as the initial presentation of undiagnosed CML and as known complication of uncontrolled CML. Hyperleukocytosis is a manifestation of uncontrolled CML and leukostasis is a complication, occurring in cases of acute myeloid leukemia (AML). Here we present a rare case of leukostasis in a patient with known CML presenting on computed tomography (CT) as intracranial masses in the chronic phase. Our goal is to discuss this rare case of leukostasis in adult CML and describe its management.
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OBJECTIVE: TissueGene-C (TG-C), a combination of human allogeneic chondrocytes and irradiated GP2-293 cells engineered to overexpress transforming growth factor-ß1 (TGF-ß1), has been developed as a novel cell-based gene therapy and a candidate for disease modifying osteoarthritis drug (DMOAD). We aim to investigate analgesic mechanism of TG-C in a pre-clinical animal model with monoiodoacetate (MIA)-induced pain. DESIGN: We used a rat MIA model of osteoarthritis (OA) pain. We examined that TG-C can regulate pain by inhibiting the upregulation of various pain mediators in both knee joint tissue and dorsal root ganglia (DRG) (n = 112) and alleviating pain behavior (n = 41) and neuronal hyperexcitability in DRG (n = 60), afferent nerve fiber (n = 24), and spinal cord (n = 35). RESULTS: TG-C significantly alleviated pain-related behavior by restoring altered dynamic weight bearing and reduced mechanical threshold of the affected hindlimb. TG-C significantly suppressed the expression of nerve growth factor (NGF) and calcitonin gene-related peptide (CGRP) in inflamed joint tissue. TG-C significantly suppressed the upregulation of tropomyosin receptor kinase A (TrkA) and nerve injury/regeneration protein (GAP43) and activation of Iba1-positive microglial cells in DRG. TG-C significantly recovered neuronal hyperexcitability by restoring RMP and firing threshold and frequency of DRG neurons, attenuating firing rates of mechanosensitive C- or Aδ-nerve fiber innervating knee joint, and lowering increased miniature and evoked excitatory postsynaptic currents (mEPSCs and eEPSCs) in the spinal cord. CONCLUSION: Our results demonstrated that TG-C exerted potent analgesic effects in a rat MIA model of OA pain by inhibiting the upregulation of pain mediators and modulating neuronal sensitization.
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Osteoartritis , Dolor , Ratas , Humanos , Animales , Ratas Sprague-Dawley , Dolor/metabolismo , Osteoartritis/terapia , Osteoartritis/tratamiento farmacológico , Analgésicos/uso terapéutico , Neuronas/metabolismo , Ganglios Espinales/metabolismo , Modelos Animales de EnfermedadRESUMEN
INTRODUCTION/BACKGROUND: Central nervous system (CNS) relapse is an infrequent but serious and challenging complication of diffuse large B-cell lymphoma (DLBCL) that carries a dismal prognosis. While several risk factors have been identified to stratify the risk for CNS relapse including the 2015 CNS internal Prognostic index (CNS-IPI), controversy still remains regarding the indication, timing, and method of CNS prophylaxis. The purpose of this study was to determine whether IT-MTX reduced the risk of CNS relapse, as well as treatment related and financial toxicity of CNS prophylaxis. PATIENTS AND METHODS: In this retrospective study, we identified 194 patients with DLBCL who received care at Loma Linda University Cancer Center between January 2010- August 2022. We evaluated the efficacy, side effect profile, and financial toxicity of IT-MTX for CNS prophylaxis in patients with DLBCL. RESULTS: In patients with intermediate to high CNS relapse risk (CNS-IPI 2-5) IT-MTX did not reduce the 1 year risk of CNS relapse (RR 1.1296, 95% CI 0.1933-6.6012, P = .08924). The median time to CNS relapse was longer in patients who had received IT-MTX (13.5 months) vs. those who did not (7 months). Thirty-eight (52.8%) patients reported adverse side effects of any kind as a result of IT-MTX administration, with 23.6% of patients developing grade 2 to 3 adverse events. The average cost for CNS-prophylaxis was estimated to be approximately $8,059.04 over a patient's treatment course, but as high as $20,140. CONCLUSIONS: These findings suggest that IT-MTX has limited and potential transient effectiveness in preventing CNS relapse. Given the high rate of side effects and significant cost of IT-MTX, we recommend that clinicians carefully consider the risks and benefits of prophylaxis before prescribing IT-MTX for CNS-prophylaxis.
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Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias del Sistema Nervioso Central , Linfoma de Células B Grandes Difuso , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Neoplasias del Sistema Nervioso Central/prevención & control , Neoplasias del Sistema Nervioso Central/patología , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/patología , Metotrexato , Recurrencia Local de Neoplasia/patología , Pronóstico , Estudios RetrospectivosRESUMEN
In the past decade, targeted therapies for solid tumors, including non-small cell lung cancer (NSCLC), have advanced significantly, offering tailored treatment options for patients. However, individuals without targetable mutations pose a clinical challenge, as they may not respond to standard treatments like immune-checkpoint inhibitors (ICIs) and novel targeted therapies. While the mechanism of action of ICIs seems promising, the lack of a robust response limits their widespread use. Although the expression levels of programmed death ligand 1 (PD-L1) on tumor cells are used to predict ICI response, identifying new biomarkers, particularly those associated with the tumor microenvironment (TME), is crucial to address this unmet need. Recently, inflammatory cytokines such as interleukin-1 beta (IL-1ß) have emerged as a key area of focus and hold significant potential implications for future clinical practice. Combinatorial approaches of IL-1ß inhibitors and ICIs may provide a potential therapeutic modality for NSCLC patients without targetable mutations. Recent advancements in our understanding of the intricate relationship between inflammation and oncogenesis, particularly involving the IL-1ß/PD-1/PD-L1 pathway, have shed light on their application in lung cancer development and clinical outcomes of patients. Targeting these pathways in cancers like NSCLC holds immense potential to revolutionize cancer treatment, particularly for patients lacking targetable genetic mutations. However, despite these promising prospects, there remain certain aspects of this pathway that require further investigation, particularly regarding treatment resistance. Therefore, the objective of this review is to delve into the role of IL-1ß in NSCLC, its participation in inflammatory pathways, and its intricate crosstalk with the PD-1/PD-L1 pathway. Additionally, we aim to explore the potential of IL-1ß as a therapeutic target for NSCLC treatment.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Antígeno B7-H1/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Inmunoterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Receptor de Muerte Celular Programada 1/genética , Microambiente Tumoral/genética , Interleucina-1betaRESUMEN
BACKGROUND: To explore whether peripheral blood neutrophils and lymphocytes are associated with longitudinal motor and cognitive decline in patients with early Parkinson's disease (PD) and, to uncover the disease-specific mechanisms underlying these associations. METHODS: Data were obtained from the Parkinson's Progression Markers Initiative cohort. We included 376 patients with recently diagnosed, drug-naïve PD and 178 matched healthy controls. The patients underwent annual assessments, including the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part 3 test to measure motor function and the Montreal Cognitive Assessment (MoCA) to measure cognitive function, for up to 8 years of follow-up. Dopamine transporter (DAT) imaging was performed at baseline and the 1-year, 2-year and 4-year follow-up visits. RESULTS: At baseline, patients with PD showed higher neutrophil and lower lymphocyte counts, resulting in a higher neutrophil-to-lymphocyte ratio (NLR) than that in healthy controls. Higher neutrophil counts were associated with a greater increase in MDS-UPDRS part 3 scores in patients with PD (estimate: 0.25, 95% CI: 0.12 to 0.37, p<0.001). Correspondingly, higher neutrophil levels were related to a greater reduction in DAT activity in the caudate (estimate: -0.007, 95% CI: -0.014 to -0.001, p=0.046) and putamen (estimate: -0.0039, 95% CI: -0.0077 to -0.0002, p=0.042). However, there were no significant effects of lymphocyte count and NLR on changes in the MDS-UPDRS part 3 and MoCA scores and striatal DAT uptake over time. CONCLUSION: Among the blood biomarkers, only a higher neutrophil count was associated with faster motor progression along with accelerated nigrostriatal dopaminergic degeneration in patients with PD. The impact of neutrophils and lymphocytes on longitudinal cognitive changes remains unclear. TRIAL REGISTRATION NUMBER: NCT01141023.
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Enfermedad de Parkinson , Humanos , Estudios de Seguimiento , Pronóstico , Neutrófilos , LinfocitosRESUMEN
INTRODUCTION: Pembrolizumab (Keytruda) is a monoclonal antibody against the programmed cell death-1 (PD-1) receptor on lymphocytes, which is one of the immune checkpoint inhibitors (ICIs) approved for multiple solid and hematologic malignancies. Although ICIs have proven to be more effective and less toxic compared to chemotherapy, there are reports of adverse side effects with ICIs. For example, pneumonitis is a potentially lethal side effect occurring in 1%-5% of patients who received ICIs in clinical trials, and there are case reports with clinical and radiological features of checkpoint inhibitor-pneumonitis (CIP). CASE REPORT: We report an unusual case of pneumonitis with atypical imaging in a patient who received pembrolizumab for metastatic p16-positive squamous cell carcinoma of the base of the tongue. We discuss the approach to the recognition and management of atypical CIP in patients on pembrolizumab with the intent to standardize workup and increase awareness among healthcare providers in the new era of immunotherapy. MANAGEMENT AND OUTCOME: Serologic workup including laboratory studies for complete blood count (CBC), lactate, procalcitonin, SARS-CoV-2 (COVID-19), Legionella, Cytomegalovirus (CMV), Coccidioides, Coxiella, and viral respiratory panel were negative for infectious processes. Since CIP was suspected, the patient was started on steroid therapy. Interval computed tomography (CT) of the chest without contrast showed a resolution of pneumonitis. DISCUSSION: In this case report, we discuss our workup of CIP and initial testing to rule out other possible causes of the patient's symptoms and radiographic findings, and management of the patient's diagnosis of atypical CIP which led to complete clinical recovery from CIP.
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Antineoplásicos Inmunológicos , COVID-19 , Carcinoma de Pulmón de Células no Pequeñas , Carcinoma de Células Escamosas , Enfermedades Pulmonares Intersticiales , Neoplasias Pulmonares , Neumonía , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , COVID-19/complicaciones , SARS-CoV-2 , Neumonía/inducido químicamente , Carcinoma de Células Escamosas/tratamiento farmacológico , Enfermedades Pulmonares Intersticiales/inducido químicamenteRESUMEN
In this narrative review article, we critically assess the current state of the osteoarthritis (OA) drug development pipeline. We discuss the current state-of-the-art in relation to the development and evaluation of candidate disease-modifying OA drugs (DMOADs) and the limitations associated with the tools and methodologies that are used to assess outcomes in OA clinical trials. We focus on the definition of DMOADs, highlight the need for an updated definition in the form of a consensus statement from all the major stakeholders, including academia, industry, regulatory agencies, and patient organizations, and provide a summary of the results of recent clinical trials of novel DMOAD candidates. We propose that DMOADs should be more appropriately targeted and investigated according to the emerging clinical phenotypes and molecular endotypes of OA. Based on the findings from recent clinical trials, we propose key topics and directions for the development of future DMOADs.
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To improve the motion detection performance of a bracelet-type sensor that uses only two tiny sensor modules developed using carbon-based conductive polymer composite films, a fuzzy-logic algorithm was developed in this study. A polyethylene terephthalate polymer film with a conductive layer composed of carbon paste was used as the integral material utilized for the composite film; a small sensor module composed of mechanical parts mounted on the film was developed to effectively detect the surface resistance variations of the film. A participant wore a bracelet sensor, which consisted of two sensor modules, on their forearm, and the resistance variations of the contact area between the forearm and the sensor modules corresponding to the flexion changes of the surface of the body due to muscle contraction and relaxation were detected. The surface resistance variations of the film were converted to voltage signals, which were used as inputs to the fuzzy logic algorithm to detect four consecutive motions of the forearm. The results demonstrated that the fuzzy-logic algorithm attained an accuracy of 94%. The fuzzy algorithm successfully detected four motions and the resting state of the forearms; moreover, it showed improved performance compared to previous research.
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Background: This study investigated the effects of lower limb movements on dynamic postural stability (DPS) during drop landing in adult women with patellofemoral pain syndrome (PFPS). Methods: Thirty-eight adult women were recruited and divided into two groups, the PFPS group and the control group. The study participants performed a single-leg drop landing from a 30 cm box, and their lower limb movements and DPS were measured. Differences between groups were examined using independent sample t-tests. In addition, stepwise multiple linear regression was used to examine the kinematic parameters that contribute to the DPS. Results: The PFPS group had significantly lower hip flexion, internal rotation, knee flexion, ankle external rotation, pelvic oblique, tilt, rotation, and higher hip abduction, knee valgus, and ankle plantarflexion. In terms of DPS, the PFPS group had a significantly higher anteroposterior and a lower mediolateral than that of the control group. In the control group, regression analysis revealed a controlled anteroposterior using knee flexion, while the PFPS group controlled mediolateral through ankle plantarflexion. Conclusions: Patients with PFPS experienced more shock on their knee joint during landing than patients in the control group with greater anteroposterior instability and lower mediolateral instability.
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In this study, we developed a fabrication method for a bracelet-type wearable sensor to detect four motions of the forearm by using a carbon-based conductive layer-polymer composite film. The integral material used for the composite film is a polyethylene terephthalate polymer film with a conductive layer composed of a carbon paste. It is capable of detecting the resistance variations corresponding to the flexion changes of the surface of the body due to muscle contraction and relaxation. To effectively detect the surface resistance variations of the film, a small sensor module composed of mechanical parts mounted on the film was designed and fabricated. A subject wore the bracelet sensor, consisting of three such sensor modules, on their forearm. The surface resistance of the film varied corresponding to the flexion change of the contact area between the forearm and the sensor modules. The surface resistance variations of the film were converted to voltage signals and used for motion detection. The results demonstrate that the thin bracelet-type wearable sensor, which is comfortable to wear and easily applicable, successfully detected each motion with high accuracy.
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Carbono , Dispositivos Electrónicos Vestibles , Antebrazo , Movimiento (Física) , PolímerosRESUMEN
This study investigated continuous visuomotor tracking capabilities between athletes and non-athlete controls using isometric force control paradigm. Nine female athletes and nine female age-matched controls performed unilateral hand-grip force control tasks with their dominant and non-dominant hands at 10% and 40% of maximal voluntary contraction (MVC), respectively. Three conventional outcome measures on force control capabilities included mean force, force accuracy, and force variability, and we additionally calculated two nonlinear dynamics variables including force regularity using sample entropy and force stability using maximal Lyapunov exponent. Finally, we performed correlation analyses to determine the relationship between nonlinear dynamics variables and conventional measures for each group. The findings indicated that force control capabilities as indicated by three conventional measures were not significantly different between athlete and non-athlete control groups. However, the athletes revealed less force regularity and greater force stability across hand conditions and targeted force levels than those in non-athlete controls. The correlation analyses found that increased force regularity (i.e., less sample entropy values) at 10% of MVC and decreased force regularity (i.e., greater sample entropy values) at 40% of MVC were significantly related to improved force accuracy and variability for the athlete group, and these patterns were not observed in the non-athlete control group. These findings suggested that the athletes may use different adaptive force control strategies as indicated by nonlinear dynamics tools.
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Atletas , Contracción Isométrica , Femenino , Gravitación , HumanosRESUMEN
The modeling method is an effective means of estimating causality as well as examining cycle pedaling efficiency. Pedaling efficiency can also be examined by an experimental method, but the experimental method can lead to contradictory results due to perturbation of the measured output parameters. Experimental studies generally yield realistic results, but it is difficult to control for all the variables of interest and to determine the causal relationships between them. The objective of this study is to investigate the pedaling efficiency and causality with considering saddle position and pedaling cadence as variables. Based on the mathematical pedaling modeling, the internal work calculation method was used to calculate the consumed mechanical energy and energy conservation percentage (Cs). The optimal saddle position with the lowest mechanical energy and the highest energy conservation percentage could be changed by the cadence. At the low cadence, the higher saddle position, and the shorter horizontal distance between the saddle and crankshaft led to higher pedaling efficiency (h: 0.95â m, d: 0.16â m, and knee angle: 28°). However, the highest pedaling efficiency was achieved at the high cadence with a saddle height (h) of 0.9â m and a horizontal distance between the saddle and the crankshaft (d) of 0.06â m (knee angle: 48°). The lowest cadence is the optimal cadence in terms of the consumed energy, but the optimal cadence was 90â r/min in terms of the energy conservation percentage. Compared to the energy consumption, the energy conservation percentage was demonstrated to influence the fatigue of a cycle rider more critically. The energy conservation percentage was highest at 90â r/min, and 90â r/min was close to the preferred cadence by the cyclist.
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Ciclismo , Extremidad Inferior , Fenómenos Biomecánicos , Humanos , Rodilla , Articulación de la RodillaRESUMEN
Once inside the host cell, DNA viruses must overcome the physical barrier posed by the nuclear envelope to establish a successful infection. The mechanism underlying this process remains unclear. Here, we show that the herpesvirus exploits the immune adaptor stimulator of interferon genes (STING) to facilitate nuclear import of the viral genome. Following the entry of the viral capsid into the cell, STING binds the viral capsid, mediates capsid docking to the nuclear pore complex via physical interaction, and subsequently enables accumulation of the viral genome in the nucleus. Silencing STING in human cytomegalovirus (HCMV)-susceptible cells inhibited nuclear import of the viral genome and reduced the ensuing viral gene expression. Overexpressing STING increased the host cell's susceptibility to HCMV and herpes simplex virus 1 by improving the nuclear delivery of viral DNA at the early stage of infection. These observations suggest that the proviral activity of STING is conserved and exploited by the herpesvirus family. Intriguingly, in monocytes, which act as latent reservoirs of HCMV, STING deficiency negatively regulated the establishment of HCMV latency and reactivation. Our findings identify STING as a proviral host factor regulating latency and reactivation of herpesviruses.
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Citomegalovirus/fisiología , ADN Viral/metabolismo , Genoma Viral/fisiología , Proteínas de la Membrana/metabolismo , Replicación Viral/fisiología , Proteínas de la Cápside/genética , Proteínas de la Cápside/metabolismo , Línea Celular , ADN Viral/genética , Regulación Viral de la Expresión Génica , Proteínas de la Membrana/genética , Interferencia de ARN , ARN Interferente Pequeño , Internalización del VirusRESUMEN
Topics concerning autonomous navigation, especially those related to positioning systems, have recently attracted increased research attention. The commonly available global positioning system (GPS) is unable to determine the positions of vehicles in GPS-shaded regions. To address this concern, this paper presents a fuzzy-logic system capable of determining the position of a moving robot in a GPS-shaded indoor environment by analyzing the chromaticity and frequency-component ratio of LED lights installed under the ceiling. The proposed system's performance was analyzed by performing a MATLAB simulation of an indoor environment with obstacles. During the simulation, the mobile robot utilized a fuzzy autonomous navigation system with behavioral rules to approach targets successfully in a variety of indoor environments without colliding with obstacles. The robot utilized the x and y coordinates of the fuzzy positioning system. The results obtained in this study confirm the suitability of the proposed method for use in applications involving autonomous navigation of vehicles in areas with poor GPS-signal reception, such as in tunnels.