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Background and aimSilver has been widely used as a topical antimicrobial agent in burn wound care. In a previous study, we demonstrated the introduction of nano-silver particles to porcine small intestinal submucosa (NS-PSIS) led to significant enhancement in antibacterial property in repairing contaminated abdominal defect. In this study, we explored the efficacy of NS-PSIS in the treatment of Pseudomonas aeruginosa-infected partial-thickness burn wounds.Methods48 male Sprague-Dawley rats were divided into four groups of equal number. Standardized and reproducible Pseudomonas aeruginosa-infected partial-thickness thermal burns wound model were created using these rats. NS-PSIS, PSIS (porcine small intestinal submucosa) or lipido-colloid dressingss (Urgotul?) were tested for 14 days to assess their ability to heal the rats’ burn wounds. Control group was without any treatment after the establishment of infected burn-wound. The wound contraction rate, animal body weight change, histological examination, and the quantification of IL-6 and C-reactive protein (CRP) were measured to evaluate the healing effects.ResultsNS-PSIS significantly promoted wound healing and recovered the normal growth of rats. There were significantly lower expression levels of pro-inflammatory cytokine (IL-6) and CRP in NS-PSIS group as compared with the PSIS or Urgotul group in the treatment of infected partial-thickness burn wounds. Histological exams revealed significant less inflammatory cells infiltrating, more re-epithelization and neovascularization in NS-PSIS group. There were also less inflammatory cells infiltrations in the major organs in NS-PSIS group.ConclusionsNano-silver modified porcine small intestinal submucosa (NS-PSIS) can be used as a biological derivative dressing for the treatment of infected partial-thickness burn wounds.  相似文献   
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Identification of deleterious variants in hereditary breast and ovarian cancer (HBOC) susceptibility genes allows for increased clinical surveillance and early detection, and could predict the response to poly (ADP‐ribose) polymerase (PARP) inhibitor in patients with advanced ovarian carcinomas. To determine the prevalence and clinical prediction factors for HBOC syndrome, 882 selected individuals underwent multigene panel testing for HBOC risk assessment during the period from January 2015 to March 2018. Overall, 176 deleterious mutations were observed in 19.50% (n = 172) of individuals. Twenty‐six of 176 mutations could not be retrieved in related public databases and were considered to be novel. Among patients with ovarian cancer, 115 deleterious mutations were identified in 429 patients (48.6%) with significant enrichment for a family history of breast or ovarian cancer syndrome (P < .05). In the breast cancer subgroup, 31 deleterious mutations were identified in 261 patients. Besides BRCA1 (8; 25.8%) and BRCA2 (11; 35.5%), the most frequently occurring genes, an additional 12 deleterious mutations (38.7%) were found in seven other susceptibility genes. Higher mutation incidence (57.9%) was observed in subjects with histories of breast and ovarian cancer. Our results highlighted the genetic heterogeneity of HBOC and the efficiency of a multigene panel in carrying out risk assessment.  相似文献   
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目的 探讨通过微信平台的远程护理对恶性肿瘤患儿生活质量和家属满意度的影响。方法 将某医院2015年1月—2018年12月收治入院的80例恶性肿瘤患儿,随机分为两组,对照组采用常规随访法进行指导教育,实验组在常规随访的基础上,通过微信平台实施远程延续性护理,观察对比两组患儿在干预前后的生活质量评分情况及和家属满意度情况。结果 干预前对照组与实验组患者的生存质量普适性核心量表评分(PedsQLTM4.0)、生存质量癌症模块量表评分(PedsQLTM3.0)比较差异均无统计学意义(P>0.05),两组患者干预前后PedsQLTM4.0与PedsQLTM3.0评分比较差异有统计学意义(P<0.05)。干预后两组患者PedsQLTM4.0评分情况,实验组为(83.77±3.14),较对照组的评分(73.18±3.85)有所升高(P<0.05);干预后两组患者PedsQLTM3.0评分情况均有所升高,实验组较对照组升高 [(71.14±12.30) vs (82.32±8.57)](P值均<0.05);实验组患儿家属满意度(97.50%)高于对照组(82.50%),(χ2=5.000,P<0.05)。结论 微信延续性护理可提高恶性肿瘤患儿的生活质量和患儿家属满意度,简易便行,值得推广。  相似文献   
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目的探讨不同转化生长因子-β(TGF-β)表达量的人羊膜间充质干细胞(hAMSCs)尾静脉移植对异种周围神经移植小鼠坐骨神经功能的恢复作用。方法从健康剖宫产产妇志愿捐献的新鲜羊膜中分离出hAMSCs,并进行纯化及鉴定。构建上调和下调TGF-β表达的慢病毒质粒,并转染纯化的hAMSCs,构建出稳定的上调或下调TGF-β表达的hAMSCs。分离并剪去C57BL/6小鼠的部分坐骨神经,将SD大鼠的坐骨神经分离剪取并移植至小鼠的坐骨神经缺损处,构建出异种周围神经移植小鼠模型。将模型小鼠按随机数字表分为对照组、未修饰的hAMSCs治疗组、高表达TGF-β的hAMSCs治疗组、低表达TGF-β的hAMSCs治疗组,每组10只。各组于造模前1 d分别经尾静脉注射磷酸盐缓冲液或相应的hAMSCs重悬液进行移植治疗。于治疗后第14天时采用DigGait步态分析系统评估各组小鼠的坐骨神经功能恢复情况。结果治疗后第14天时,高表达TGF-β的hAMSCs治疗组小鼠的坐骨神经功能指数(-25.820±0.286)明显高于低表达TGF-β的hAMSCs治疗组(-33.413±0.920)和未修饰的hAMSCs治疗组(-30.755±0.421),差异均有统计学意义(P<0.05)。结论高表达TGF-β的hAMSCs尾静脉移植能够更有效地改善异种周围神经移植小鼠的坐骨神经功能,其可能成为周围神经损伤治疗的新突破口。  相似文献   
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1. Corydaline, an isoquinoline alkaloid obtained from the rhizomes of Corydalis yanhusuo, exhibits anti-acetylcholinesterase, anti-angiogenic, anti-allergic and gastric-emptying activities. In this study, a rapid and reliable ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) method was developed and employed for the comprehensive study of the metabolites of corydaline in rats.

2. Altogether, 43 metabolites were identified in the plasma (11), bile (9), urine (34) and feces (21) of rats after oral administration of corydaline at a dose of 4.5mg/kg.

3. It was demonstrated that demethylation, hydroxylation, sulfation and glucuronidation were the major metabolic transformation pathways. Among these, two metabolites were identified as tetrahydropalmatine and isocorybulbine, and 33 phase I and phase II products were inferred to be new metabolites arising from the in vivo metabolism of corydaline.

4. Importantly, this research provides scientific and reliable support for full understanding of the metabolic profiles of corydaline and the results could help to elucidate its safety and efficacy.  相似文献   

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Hyperexcitability of neural network is a key neurophysiological mechanism in several neurological disorders including epilepsy, neuropathic pain, and tinnitus. Although standard paradigm of pharmacological management of them is to suppress this hyperexcitability, such as having been exemplified by the use of certain antiepileptic drugs, their frequent refractoriness to drug treatment suggests likely different pathophysiological mechanism. Because the pathogenesis in these disorders exhibits a transition from an initial activity loss after injury or sensory deprivation to subsequent hyperexcitability and paroxysmal discharges, this process can be regarded as a process of functional compensation similar to homeostatic plasticity regulation, in which a set level of activity in neural network is maintained after injury-induced activity loss through enhanced network excitability. Enhancing brain activity, such as cortical stimulation that is found to be effective in relieving symptoms of these disorders, may reduce such hyperexcitability through homeostatic plasticity mechanism. Here we review current evidence of homeostatic plasticity in the mechanism of acquired epilepsy, neuropathic pain, and tinnitus and the effects and mechanism of cortical stimulation. Establishing a role of homeostatic plasticity in these disorders may provide a theoretical basis on their pathogenesis as well as guide the development and application of therapeutic approaches through electrically or pharmacologically stimulating brain activity for treating these disorders.  相似文献   
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