3 resultados para Blast traumatic brain injury
em Digital Commons at Florida International University
Resumo:
This study investigated the use of treatment theories and procedures for postural control training used by Occupational Therapists (OTs) when working with hemiplegic adults who have had cerebrovascular accident (CVA) or traumatic brain injury (TBI). The method of data collection was a national survey of 400 randomly selected physical disability OTs with 127 usable surveys returned. Results showed that the most common used treatment theory was neurodevelopmental treatment (NDT), followed by motor relearning program (MRP), proprioceptive neuromuscular facilitation (PNF), Brunnstrom's approach, and the approach of Rood. The most common treatment posture used was sitting, followed by standing, mat activity, equilibrium reaction training, and walking. The factors affecting the use of various treatment theories procedures were years certified, years of clinical experience, work situation and work status. Pearson correlation coefficient analyses found significant positive relationships between treatment theories and postures. There were significant high correlations between usage of all pairs of treatment procedures. ^
Resumo:
The reactions of nitrones with free radicals have been widely studied both in vitro and in vivo. In comparison to classical chain-breaking phenolic antioxidants (such as Vitamin E and butylated hydroxytoluene [BHT]), conventional phenyl-substituted nitrones have much higher oxidation potentials. Azulenyl-substituted nitrones have lower oxidation potentials than conventional nitrones and react efficiently with free radicals in vitro and in vivo. The design and synthesis of novel azulenyl nitrones with yet lower oxidation potentials, prepared from commercially available guaiazulene, has produced several 1,2-trans -bis-azulenyl ethene compounds with enhanced antioxidant activity. A convenient 1H NMR-based assay for assessing the potency of chain-breaking antioxidants has shown these novel nitrones to be more than 300 times more potent in inhibiting the free radical-mediated aerobic peroxidation of cumene than α-phenyl-N-tert-butyl nitrone (PBN) and the experimental stroke drug NXY-059. The low oxidation potential of these novel nitrones and the stability of the corresponding radical cation have been implicated in the explanation of the increased antioxidant potency of these second generation azulenyl nitrones. Based on the results of these in vitro studies, the first of these novel compounds, stilbazulenyl nitrone (STAZN), was investigated in animal models of disease known to involve free radical-mediated pathology. In view of STAZN's marked lipophilicity and anticipated blood brain barrier permeability, neurodegenerative conditions were investigated. All animal experiments were performed at the University of Miami by members of the Ginsberg research group. STAZN was neuroprotective in traumatic brain injury in rats. It also provided exceptional neuroprotection in an animal model of stroke. The concentration of STAZN required for neuroprotection was 300–600 times less than doses of PBN or NXY-059 required for similar effect. Thus, the benefits of greater antioxidant potency sought by lowering the oxidation potential of nitrones appear to have been reaped both in vitro and in vivo. In spite of the challenges and difficulties in understanding free radical-mediated pathology, this work establishes that considerations such as redox potential and lipophilicity can provide a very fruitful rationale for the design of therapeutic azulenyl nitrone antioxidants. ^
Resumo:
Alzheimer’s disease (AD) is neuropathologically characterized by excessive beta -amyloid (Aβ) plaques and neurofibrillary tangles composed of hyperphosphorylated tau in the brain. Although the etiology of genetic cases of AD has been attributed to mutations in presenilin and amyloid precursor protein (APP) genes, in most sporadic cases of AD, the etiology is still unknown and various predisposing factors could contribute to the pathology of AD. Predominant among these possible predisposing factors that have been implicated in AD are age, hypertension, traumatic brain injury, diabetes, chronic neuroinflammation, alteration in calcium levels and oxidative stress. Since both inflammation and altered calcium levels are implicated in the pathogenesis of AD, we wanted to study the effect of altered levels of calcium on inflammation and the subsequent effect of selective calcium channel blockers on the production of pro-inflammatory cytokines and chemokines. Our hypothesis is that Aβ, depending on it conformation, may contribute to altered levels of intracellular calcium in neurons and glial cells. We wanted to determine which conformation of Aβ was most pathogenic in terms of increasing inflammation and calcium influx and further elucidate the possibility of a link between altered calcium levels and inflammation. In addition, we wanted to test whether calcium channel blockers could inhibit the inflammation mediated by the most pathogenic form of Aβ, by antagonizing the calcium influx triggered by Aβ. Our results in human glial and neuronal cells demonstrate that the high molecular weight oligomers are the most potent at stimulating the release of pro-inflammatory cytokines IL-6 and IL-8 as well as increasing intracellular levels of calcium compared to other conformations of Aβ. Further, L-type calcium channel blockers and calmodulin kinase inhibitors are able to significantly reduce the levels of IL-6 and IL-8. These results suggest that Aβ-induced alteration of intracellular calcium levels contributes to its pro-inflammatory effect.