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721.
Cognitive deficits have been observed in patients with multiple sclerosis (MS) due to hippocampal insults. Antioxidant vitamins D and E are suggested for patients suffering from neurodegenerative diseases like MS, while their mechanisms of action are not well understood. Here, we have tried to study the effects of these vitamins on demyelination, cell death, and remyelination of rat hippocampus following local ethidium bromide (EB) injection. Animals received 100 mg/kg vitamin E or 5 μg/kg of vitamin D3 for 2, 7, or 28 days. The extent of demyelination, myelin staining intensity, and expression of myelin basic protein and caspase-3 were investigated using histological and immunoblotting verification. Administration of EB alone caused demyelination, cell death, and afterward an endogenous repair. Vitamins E and D3 reduced the EB-induced damage and increased the endogenous remyelination of hippocampus. Although the anti-apoptotic effect of these vitamins and protection against demyelination were predictable based on their antioxidant effect, our results indicated the positive effect of vitamins E and D3 on process of remyelination by endogenous progenitor cells and supported their possible therapeutic effects in the context of demyelinating diseases like MS.  相似文献   
722.
Degeneration of intervertebral disk (IVD) has been increased in recent years. The lumbar herniation can be cured using conservative and surgical procedures. Surgery is considered after failure of conservative treatment. Partial discectomy, fusion, and total disk replacement (TDR) are also common surgical treatments for degenerative disk disease. However, due to limitations and disadvantages of the current treatments, many studies have been carried out to approach the best design of mimicking natural disk. Recently, a new method of TDRs has been introduced using nature deformation of IVD by reinforced fibers of annulus fibrosis. Nonetheless, owing to limitations of experimental works on the human body, numerical studies of IVD may help to understand load transfer and biomechanical properties within the disks with reinforced fibers. In this study, a three-dimensional (3D) finite element model of the L2-L3 disk vertebrae unit with 12 vertical fibers embedded into annulus fibrosis was constructed. The IVD was subjected to compressive force, bending moment, and axial torsion. The most important parameters of disk failures were compared to that of experimental data. The results showed that the addition of reinforced fibers into the disk invokes a significant decrease of stress in the nucleus and annulus. The findings of this study may have implications not only for developing IVDs with reinforced fibers but also for the application of fiber reinforced IVD in orthopedics surgeries as a suitable implant.  相似文献   
723.
In this paper, three different reactions of nanoparticles and proteins are explained. As a model system, the interactions of birnessite, which is a common manganese oxide in the environment, and bovine serum albumin, as a protein that has a strong affinity for a variety of inorganic molecules, are studied. The author proposes that the cofactor-formation in particular enzymes may be considered as a biomineralization in the presence of the protein. One of the numerous and very small nanoparticles produced in the presence of protein could be formed in an appropriate location in proteins and be used as a primitive inorganic core (cofactor) of enzyme.  相似文献   
724.
Molecular Biology Reports - Investigating the interaction of diabetes with ischemic postconditioning (IPostC)-associated cardioprotection in myocardial ischemia/reperfusion (I/R) damage is of great...  相似文献   
725.
Prostate cancer (PCa) is the most common noncutaneous cancer among men, accounting for 10?% of male cancer-related deaths worldwide. The etiology of PCa is largely unknown, although multiple environmental and lifestyle factors such as ultraviolet irradiation, smoking, and diet might increase the risk of the disease. Risk of disease varies most prominently with age, ethnicity, family history, and diet. The multifunctional cytokine tumor necrosis factor alpha (TNF-α) has an important role in the pathogenesis of inflammatory, autoimmune and malignant diseases. In this case control study 150 Prostate cancer patients and 150 age matched benign prostate hyperplasia (BPH) and equal number of healthy control groups were involved. The aim of this study was to analyze the effect of TNF-α-308 (G/A) polymorphism on risk of prostate cancer on north Indian prostate cancer patients. The polymerase chain reaction (PCR) technique was utilized to genotype TNF-α-308 (G/A) polymorphism. The present study showed statistically significant increased risk of prostate cancer among individuals that carried the A allele of TNF-α-308 gene (OR?=?1.81, 95?% CI 1.00–3.481, p?=?0.03).  相似文献   
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