536 research outputs found
Augmenting Hand and Arm Function for Persons with Hemiparesis
Background. Hand and arm dysfunction due to neural disorders significantly influences quality of life. Activity-based training has been found to improve function. These improvements could be augmented with transcutaneous spinal cord stimulation (tSCS) due to the modulatory effect it has on spinal and supraspinal networks. Objective. The primary aim is to determine if a 4-week training program will improve hand and arm function. The secondary aim is to determine if the addition of tSCS to a second 4-week training session will further improve function. Design. This is a pre-posttest, controlled trial for persons 10-75 years of age, \u3e6 months post stroke or with unilateral cerebral palsy.Methods. Participants will engage in two 4-week training periods, 3x/week for 2 hours/day. The 1st period will include unimanual and bimanual training alone. The 2nd period will be augmented with low frequency tSCS to the C5-T1 spinal region. Stimulation intensity will be based on individual muscle activation during 3 tasks: 1) grip dynamometry; 2) grip-lift; and 3) target pointing. Outcome measures taken before, midway, and after training are: Canadian Occupational Performance Measure (COPM), dexterity, daylong arm use, grip/pinch strength, sensibility, questionnaires, bilateral hand/arm surface electromyography, and Upper Extremity Fugl-Meyer (UEFM). Results: Nine participants have completed the 1st 4-week training period without tSCS. Individual data reveals improvements in the COPM, Grip strength, dexterity, and the UEFM. Findings for other measures after the 1st period are mixed or in process. Conclusion: Preliminary findings from this ongoing study reveal that participants made improvements in most measures. The next phase of the study will determine if the addition of tSCS to training further augments hand and arm function
Transduction of the Geomagnetic Field as Evidenced from Alpha-band Activity in the Human Brain
Magnetoreception, the perception of the geomagnetic field, is a sensory modality well-established across all major groups of vertebrates and some invertebrates, but its presence in humans has been tested rarely, yielding inconclusive results. We report here a strong, specific human brain response to ecologically-relevant rotations of Earth-strength magnetic fields. Following geomagnetic stimulation, a drop in amplitude of EEG alpha oscillations (8-13 Hz) occurred in a repeatable manner. Termed alpha event-related desynchronization (alpha-ERD), such a response has been associated previously with sensory and cognitive processing of external stimuli including vision, auditory and somatosensory cues. Alpha-ERD in response to the geomagnetic field was triggered only by horizontal rotations when the static vertical magnetic field was directed downwards, as it is in the Northern Hemisphere; no brain responses were elicited by the same horizontal rotations when the static vertical component was directed upwards. This implicates a biological response tuned to the ecology of the local human population, rather than a generic physical effect.
Biophysical tests showed that the neural response was sensitive to static components of the magnetic field. This rules out all forms of electrical induction (including artifacts from the electrodes) which are determined solely on dynamic components of the field. The neural response was also sensitive to the polarity of the magnetic field. This rules out free-radical 'quantum compass' mechanisms like the cryptochrome hypothesis, which can detect only axial alignment. Ferromagnetism remains a viable biophysical mechanism for sensory transduction and provides a basis to start the behavioral exploration of human magnetoreception
The Mediational Role of Motivation in the Model of Motor Development in Childhood: A Longitudinal Study
The aim of this study was twofold: first, to examine the stability of the hypothesized conceptual model of motor development (without and with including various types of motivation) when children are followed up one-year later, and second to examine longitudinally whether changes in one model variable predict changes in other variables, according to the hypothesized pathways in the model. A sample of 361 Spanish students (50.7% girls, 8â11 years old) voluntarily participated in this study. In relation to the first aim, structural equation modeling revealed the expected positive relationship between the model variables in both measurement times. That is: actual motor competence (MC) predicted physical activity (PA) (p \u3c .001), perceived MC mediated the relationship between actual MC and PA (p \u3c .001), and autonomous motivation mediated the relationship between perceived MC and PA (p \u3c .05). Moreover, the comparison of the invariance analysis showed non-practical differences between the unconstrained model and the constrained model, supporting the stability of the model over time. In relation to the second aim, the hypothesized model in Time 2 controlling for Time 1 values showed that changes in childrenâs actual MC positively predicted changes in their perceived MC (p \u3c .001), which in turn, predicted changes in their autonomous motivation (p \u3c .001), and PA (p \u3c .001) at Time 2. Based on these findings Physical Education teachers are recommended to foster childrenâs actual and perceived MC as well as their autonomous motivation over time in order to promote PA strategies for lifelong health
miR-31-3p functions as a tumor suppressor by directly targeting GABBR2 in prostate cancer
MicroRNAs are key regulators of gene expression in tumorigenesis. In this study, we investigated the tumor-suppressive function of miR-31-3p. Analysis of the Gene Expression Omnibus database revealed that the expression of miR-31-3p in prostate cancer tissues is lower than that in adjacent normal tissues from patients with prostate cancer. Moreover, miR-31-3p induces apoptosis in DU145, PC-3, and LNCap prostate cancer cells, while those transfected with miR-31-3p exhibit significantly decreased cell proliferation, migration, invasiveness, and tumor sphere-forming ability, as determined using the cell counting kit-8, transwell, and sphere-forming assays. Further analysis revealed that GABBR2 is a direct target of miR-31-3p. Within a DU145 xenograft murine model, intratumoral injection of a miR-31-3p mimic suppresses tumor growth. Taken together, the findings of this study suggest that miR-31-3p performs a novel tumor-suppressive function in prostate cancer and may represent a novel target for anti-prostate cancer miRNA therapeutics
LYVE-1+ macrophages form a collaborative CCR5-dependent perivascular niche that influences chemotherapy responses in murine breast cancer
Tumor-associated macrophages (TAMs) are a heterogeneous population of cells that facilitate cancer progression. However, our knowledge of the niches of individual TAM subsets and their development and function remain incomplete. Here, we describe a population of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1)-expressing TAMs, which form coordinated multi-cellular ânestâ structures that are heterogeneously distributed proximal to vasculature in tumors of a spontaneous murine model of breast cancer. We demonstrate that LYVE-1+ TAMs develop in response to IL-6, which induces their expression of the immune-suppressive enzyme heme oxygenase-1 and promotes a CCR5-dependent signaling axis, which guides their nest formation. Blocking the development of LYVE-1+ TAMs or their nest structures, using gene-targeted mice, results in an increase in CD8+ T cell recruitment to the tumor and enhanced response to chemotherapy. This study highlights an unappreciated collaboration of a TAM subset to form a coordinated niche linked to immune exclusion and resistance to anti-cancer therapy
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