72 research outputs found
Effects of Noise Electrical Stimulation on Proprioception, Force Control, and Corticomuscular Functional Connectivity
Sensory afferent inputs play an important role in neuromuscular functions. Subsensory level noise electrical stimulation enhances the sensitivity of peripheral sensory system and improves lower extremity motor function. The current study aimed to investigate the immediate effects of noise electrical stimulation on proprioceptive senses and grip force control, and whether there are associated neural activities in the central nervous system. Fourteen healthy adults participated in 2 experiments on 2 different days. In day 1, participants performed grip force and joint proprioceptive tasks with and without (sham) noise electrical stimulation. In day 2, participants performed grip force steady hold task before and after 30-min noise electrical stimulation. Noise stimulation was applied with surface electrodes secured along the course of the median nerve and proximal to the coronoid fossa EEG power spectrum density of bilateral sensorimotor cortex and coherence between EEG and finger flexor EMG were calculated and compared. Wilcoxon Signed-Rank Tests were used to compare the differences of proprioception, force control, EEG power spectrum density and EEG-EMG coherence between noise electrical stimulation and sham conditions. The significance level (alpha) was set at 0.05. Our study found that noise stimulation with optimal intensity could improve both force and joint proprioceptive senses. Furthermore, individuals with higher gamma coherence showed better force proprioceptive sense improvement with 30-min noise electrical stimulation. These observations indicate the potential clinical benefits of noise stimulation on individuals with impaired proprioceptive senses and the characteristics of individuals who might benefit from noise stimulation
Reduced expression of alpha-1,2-mannosidase I extends lifespan in Drosophila melanogaster and Caenorhabditis elegans
Exposure to sub-lethal levels of stress, or hormesis, was a means to induce longevity. By screening for mutations that enhance resistance to multiple stresses, we identified multiple alleles of alpha-1,2-mannosidase I (mas1) which, in addition to promoting stress resistance, also extended longevity. Longevity enhancement is also observed when mas1 expression is reduced via RNA interference in both Drosophila melanogaster and Caenorhabditis elegans. The screen also identified Edem1 (Edm1), a gene downstream of mas1, as a modulator of lifespan. As double mutants for both mas1 and Edm1 showed no additional longevity enhancement, it appeared that both mutations function within a common pathway to extend lifespan. Molecular analysis of these mutants revealed that the expression of BiP, a putative biomarker of dietary restriction (DR), is down-regulated in response to reductions in mas1 expression. These findings suggested that mutations in mas1 may extend longevity by modulating DR
Infection Control and SARS Transmission among Healthcare Workers, Taiwan
This study found infrequent transmission of severe acute respiratory syndrome (SARS) coronavirus to healthcare workers involved in the care of the first five case-patients in Taiwan, despite a substantial number of unprotected exposures. Nonetheless, given that SARS has been highly transmissible on some occasions, we still recommend strict precautions
The bracteatus pineapple genome and domestication of clonally propagated crops
Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a 'one-step operation'. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars 'Smooth Cayenne' and 'Queen' exhibited ancient and recent admixture, while 'Singapore Spanish' supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops
Stem Cell-Based Neuroprotective and Neurorestorative Strategies
Stem cells, a special subset of cells derived from embryo or adult tissues, are known to present the characteristics of self-renewal, multiple lineages of differentiation, high plastic capability, and long-term maintenance. Recent reports have further suggested that neural stem cells (NSCs) derived from the adult hippocampal and subventricular regions possess the utilizing potential to develop the transplantation strategies and to screen the candidate agents for neurogenesis, neuroprotection, and neuroplasticity in neurodegenerative diseases. In this article, we review the roles of NSCs and other stem cells in neuroprotective and neurorestorative therapies for neurological and psychiatric diseases. We show the evidences that NSCs play the key roles involved in the pathogenesis of several neurodegenerative disorders, including depression, stroke and Parkinson’s disease. Moreover, the potential and possible utilities of induced pluripotent stem cells (iPS), reprogramming from adult fibroblasts with ectopic expression of four embryonic genes, are also reviewed and further discussed. An understanding of the biophysiology of stem cells could help us elucidate the pathogenicity and develop new treatments for neurodegenerative disorders. In contrast to cell transplantation therapies, the application of stem cells can further provide a platform for drug discovery and small molecular testing, including Chinese herbal medicines. In addition, the high-throughput stem cell-based systems can be used to elucidate the mechanisms of neuroprotective candidates in translation medical research for neurodegenerative diseases
T4 Sympathectomy for Palmar Hyperhidrosis: An Effective Approach that Simultaneously Minimizes Compensatory Hyperhidrosis
Compensatory hyperhidrosis (CH) is the most troublesome side effect after T2 sympathectomy for palmar hyperhidrosis (PH). The aim of this study was to evaluate whether T4 ganglion interruption for PH is an effective approach that can simultaneously minimize the rate of CH. Between July 2001 and July 2003, 84 PH patients undergoing bilateral thoracoscopic T4 sympathectomy were followed up in the outpatient clinic and by telephone questionnaire. Rates of success, regret, CH, recurrence, and complications were recorded. The follow-up period ranged from 18 to 42 months. All excessive hand sweating was stopped. Only two patients had mild CH that did not affect their daily activities. No patients had recurrence or regret. The only other complication was that four patients had postoperative minimal residual pneumothorax, which needed no treatment. All patients were satisfied with the outcome. T4 sympathectomy was an effective method to cure PH. The success rate was 100%. The rate of CH was remarkably low compared with T2 sympathetic ganglionic interruption
Valproic acid exerts an anti-tumor effect on tongue cancer sas cells in vitro and in vivo
Background: Valproic acid (VPA) is a drug approved by the Food and Drug Administration for epilepsy and bipolar disorders. It is also a known histone deacetylase inhibitor and has been evaluated as an anti-cancer agent. However, the in vitro and in vivo anti-tumor effect of VPA on human tongue cancer has not been evaluated. Materials and Methods: We tested VPA for its anti-tumor activity on the human tongue cancer (SAS) cell line in vitro and in vivo in a tumor xenograft model in mice. The effect of VPA on the cell cycle and apoptosis was examined. Results: Growth inhibition was noted when SAS, squamous cell carcinoma 25 and OECM-1 cells were treated with various doses of VPA for 24-72 h, and it was found that VPA treatment caused G1 arrest and apoptosis in SAS cells. VPA also inhibited the phosphorylation of Akt and ERK in SAS cells in vitro. Tumor growth inhibition was observed in NOD/SCID mice bearing xenografts of human tongue cancer that were treated with a VPA dose of 400 mg/kg/day. Conclusions: This study demonstrates that VPA can inhibit the growth of human tongue cancer cells in vitro and in vivo without causing any significant adverse effects
Induced pluripotent stem cell therapy ameliorates hyperoxia-augmented ventilator-induced lung injury through suppressing the Src pathway.
BACKGROUND: High tidal volume (VT) mechanical ventilation (MV) can induce the recruitment of neutrophils, release of inflammatory cytokines and free radicals, and disruption of alveolar epithelial and endothelial barriers. It is proposed to be the triggering factor that initiates ventilator-induced lung injury (VILI) and concomitant hyperoxia further aggravates the progression of VILI. The Src protein tyrosine kinase (PTK) family is one of the most critical families to intracellular signal transduction related to acute inflammatory responses. The anti-inflammatory abilities of induced pluripotent stem cells (iPSCs) have been shown to improve acute lung injuries (ALIs); however, the mechanisms regulating the interactions between MV, hyperoxia, and iPSCs have not been fully elucidated. In this study, we hypothesize that Src PTK plays a critical role in the regulation of oxidants and inflammation-induced VILI during hyperoxia. iPSC therapy can ameliorate acute hyperoxic VILI by suppressing the Src pathway. METHODS: Male C57BL/6 mice, either wild-type or Src-deficient, aged between 2 and 3 months were exposed to high VT (30 mL/kg) ventilation with or without hyperoxia for 1 to 4 h after the administration of Oct4/Sox2/Parp1 iPSCs at a dose of 5×10(7) cells/kg of mouse. Nonventilated mice were used for the control groups. RESULTS: High VT ventilation during hyperoxia further aggravated VILI, as demonstrated by the increases in microvascular permeability, neutrophil infiltration, macrophage inflammatory protein-2 (MIP-2) and plasminogen activator inhibitor-1 (PAI-1) production, Src activation, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, and malaldehyde (MDA) level. Administering iPSCs attenuated ALI induced by MV during hyperoxia, which benefited from the suppression of Src activation, oxidative stress, acute inflammation, and apoptosis, as indicated by the Src-deficient mice. CONCLUSION: The data suggest that iPSC-based therapy is capable of partially suppressing acute inflammatory and oxidant responses that occur during hyperoxia-augmented VILI through the inhibition of Src-dependent signaling pathway
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