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991.
Secondary damage is a critical determinant of the functional outcome in patients with spinal cord injury (SCI), and involves multiple mechanisms of which the most important is the loss of nerve cells mediated by multiple factors. Autophagy can result in cell death, and plays a key role in the development of SCI. It has been recognized that valproic acid (VPA) is neuroprotective in certain experimental animal models, however, the levels of autophagic changes in the process of neuroprotection by VPA treatment following SCI are still unknown. In the present study, we determined the extent of autophagy after VPA treatment in a rat model of SCI. We found that both the mRNA and protein levels of Beclin-1 and LC3 were significantly increased at 1, 2, and 6 h after SCI and peaked at 2 h; however, Western blot showed that autophagy was markedly decreased by VPA treatment at 2 h post-injury. Besides, post-SCI treatment with VPA improved the Basso-Beattie-Bresnahan scale, increased the number of ventral horn motoneurons, and reduced myelin sheath damage compared with vehicle-treated animals at 42 days after SCI. Together, our results demonstrated the characteristics of autophagy expression following SCI, and found that VPA reduced autophagy and enhanced motor function.  相似文献   
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Major depressive disorder is prevalent worldwide, and only about half of those affected will experience no further episodes or symptoms. Additionally, depressive symptoms can be challenging to identify, with many patients going undiagnosed despite a wide variety of available treatment options. Antidepressants are the cornerstone of depression treatment; however, a large number of factors must be considered in selecting the treatment best suited to the individual. To help support physicians in this process, international and national treatment guidelines have been developed. This review evaluates the current use of antidepressant treatment for major depressive disorder in six Asian countries (China, Korea, Malaysia, Philippines, Taiwan, and Thailand). No remarkable differences were noted between Asian and international treatment guidelines or among those from within Asia as these are adapted from western guidelines, although there were some local variations. Importantly, a shortage of evidence‐based information at a country level is the primary problem in developing guidelines appropriate for Asia, so most of the guidelines are consensus opinions derived from western research data utilized in western guidelines. Treatment guidelines need to evolve from being consensus based to evidence based when evidence is available, taking into consideration cost/effectiveness or cost/benefit with an evidence‐based approach that more accurately reflects clinical experience as well as the attributes of each antidepressant. In everyday practice, physicians must tailor their treatment to the patient's clinical needs while considering associated external factors; better tools are needed to help them reach the best possible prescribing decisions which are of maximum benefit to patients.  相似文献   
996.
BackgroundA growing body of findings illustrates the importance of state-dependency in studies using brain stimulation.ObjectiveWe aimed to investigate the effects of tDCS priming followed by rTMS applied over the right dorsolateral prefrontal cortex (DLPFC) on emotional working memory.MethodsIn a randomized single-blind within-subjects design, participants performed an emotional 3-back task at baseline and after tDCS priming (anodal, cathodal) and subsequent low-frequency rTMS (active, sham) of the right DLPFC. Stimuli consisted of words related to the distinct emotion categories fear and anger as well as neutral words.ResultsTask accuracy increased for fear-related words and decreased for neutral words across stimulation conditions. No general state-dependent effects of prefrontal rTMS on working memory were found. We further showed a detrimental effect of negative emotional content on working memory performance.ConclusionsOur findings support a hemispheric lateralization of emotion processing by demonstrating that the withdrawal-related emotion fear is associated with the right DLPFC and contribute to clarifying the interaction between working memory and emotion.  相似文献   
997.
The miniature pig is an optimal animal model for studying nervous system disease because of its physiologic and pathologic features. However, the rete mirabile composed of arteries and veins at the skull base limits their application as a model of ischemic stroke by middle cerebral artery occlusion. The present study investigated the possibility of establishing an ischemic stroke model in the miniature pig by blocking the skull base retia with sodium alginate microspheres. Three Bama miniature pigs were used. Using the monitor of C-arm X-ray machine, sodium alginate microspheres (100-300 μm), a novel embolic material, were injected through the femoral artery, aortic arch, common carotid artery, ascending pharyngeal artery and the retia. Results were evaluated using carotid arteriography, MRI, behavior observation and histology. The unilateral rete mirabile was completely blocked, resulting in disturbance in blood supply to the basal ganglia, astasia of the right hind limb and salivation. MRI and hematoxylin-eosin staining showed an evident infarction focus in the basal ganglia. These findings indicate that sodium alginate microspheres are a suitable embolic material for blocking the skull base retia in miniature pigs to establish an ischemic stroke models.  相似文献   
998.
As a synthetic polypeptide water-soluble poly(l-glutamic acid) (PLGA) was designed to fabricate scaffolds for cartilage tissue engineering. Chitosan (CHI) has been employed as a physical cross-linking component in the construction of scaffolds. PLGA/CHI scaffolds act as sponges with a swelling ratio of 760 ± 45% (mass%), showing promising biocompatibility and biodegradation. Autologous adipose-derived stem cells (ASCs) were expanded and seeded on PLGA/CHI scaffolds, ASC/scaffold constructs were then subjected to chondrogenic induction in vitro for 2 weeks. The results showed that PLGA/CHI scaffolds could effectively support ASC adherence, proliferation and chondrogenic differentiation. The ASCs/scaffold constructs were then transplanted to repair full thickness articular cartilage defects (4 mm in diameter, to the depth of subchondral bone) created in rabbit femur trochlea. Histological observations found that articular defects were covered with newly formed cartilage 6 weeks post-implantation. After 12 weeks the regenerated cartilage had integrated well with the surrounding native cartilage and subchondral bone. Toluidine blue and immunohistochemical staining confirmed similar accumulation of glycosaminoglycans and type II collagen in engineered cartilage as in native cartilage 12 weeks post-implantation. The result was further supported by quantitative analysis of extracellular matrix deposition. The compressive modulus of the engineered cartilage increased significantly from 30% of that of normal cartilage at 6 weeks to 83% at 12 weeks. Cyto-nanoindentation also showed analogous biomechanical behavior of the engineered cartilage to that of native cartilage. The results of the present study thus demonstrate the potentiality of PLGA/CHI scaffolds in cartilage tissue engineering.  相似文献   
999.
Cancer treatment-related bone loss has become growing problematic, especially in breast and prostate cancer treated with hormone/endocrine therapy, chemotherapy and radiotherapy. However, bone loss caused by targeted therapy in cancer patients is largely unknown yet. In present study, a kinase inhibitors screen was applied for MC3T3-E1, a murine osteoprogenitor cell line, and seven kinase inhibitors (GSK1838705A, PF-04691502, Dasatinib, Masitinib, GDC-0941, XL880 and Everolimus) were found to suppress the cell viability with dose- and time-dependent manner. The most interesting is that many kinase inhibitors (such as lapatinib, erlotinib and sunitinib) can promote MC3T3-E1 cell proliferation at 0.01 μM. 4 out of 7 inhibitors were selected to perform the functional study and found that they lead to cell cycle dysregulation, treatments of PF-04691502 (AKT inhibitor), Dasatinib (Src inhibitor) and Everolimus (mTOR inhibitor) lead to G1 arrest of MC3T3-E1 cells via downregulation of cyclin D1 and p-AKT, whereas XL880 (MET and VEGFR inhibitor) treatment results in increase of sub-G1 and G2/M phase by upregulation of p53 protein. Our work provides important indications for the comprehensive care of cancer patients treated with some targeted drugs.  相似文献   
1000.
Infection of domestic cats with (H1N1) pandemic 2009 (pdm09) influenza A virus has recently been documented. In this paper, we report for the first time the sporadically current seroprevalence of (H1N1) pdm09 influenza A virus infection in cats in China. Thirteen of 1,080 sera were found positive by nucleoprotein (NP)-specific enzyme-linked immunosorbent assays (ELISAs) in different cat populations in southern China. It is very important to stress further surveillance of pandemic (H1N1) 2009 influenza A virus in cats in southern China.  相似文献   
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