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41.
Objective
To investigate the effect of surgical decompression on painful diabetic peripheral neuropathy (DPN) patients and discuss the role which pain distribution and characterization play in the management of painful DPN as well as the underlying mechanism involved.Methods
A total of 306 patients with painful diabetic lower-extremity neuropathy were treated with Dellon surgical nerve decompression in our department. Clinical evaluation including Visual analogue scale (VAS), Brief Pain Inventory Short Form for diabetic peripheral neuropathy (BPI-DPN) questionnaire, two-point discrimination (2-PD), nerve conduction velocity (NCV) and high-resolution ultrasonography (cross-sectional area, CSA) were performed in all cases preoperatively, and at 6 month intervals for 2 years post-decompression. The patients who underwent surgery were retrospectively assigned into two subgroups (focal and diffuse pain) according to the distribution of the diabetic neuropathic pain. The control group included 92 painful DPN patients without surgery.Results
The levels of VAS, scores in BPI-DPN, 2-PD, NCV results and CSA were all improved in surgical group when compared to the control group (P<0.05). More improvement of VAS, scores in BPI-DPN and CSA was observed in focal pain group than that in diffuse group (P<0.05).Conclusions
Efficacy of decompression of multiple lower-extremity peripheral nerves in patients with painful diabetic neuropathy was confirmed in this study. While both focal and diffuse group could benefit from surgical decompression, pain relief and morphological restoration could be better achieved in focal group. 相似文献42.
43.
Beiping Zhong Bing Cheng Xiaoming Huang Qian Xiao Zhitong Niu Yu-feng Chen Qiang Yu Wenyu Wang Xiao-Jian Wu 《Cell death & disease》2022,13(1)
Cancer-associated fibroblasts (CAFs) have been shown to play a strong role in colorectal cancer metastasis, yet the underlying mechanism remains to be fully elucidated. Using CRC clinical samples together with ex vivo CAFs-CRC co-culture models, we found that CAFs induce expression of Leucine Rich Alpha-2-Glycoprotein 1(LRG1) in CRC, where it shows markedly higher expression in metastatic CRC tissues compared to primary tumors. We further show that CAFs-induced LRG1 promotes CRC migration and invasion that is concomitant with EMT (epithelial-mesenchymal transition) induction. In addition, this signaling axis has also been confirmed in the liver metastatic mouse model which displayed CAFs-induced LRG1 substantially accelerates metastasis. Mechanistically, we demonstrate that CAFs-secreted IL-6 (interleukin-6) is responsible for LRG1 up-regulation in CRC, which occurs through a direct transactivation by STAT3 following JAK2 activation. In clinical CRC tumor samples, LRG1 expression was positively correlated with CAFs-specific marker, α-SMA, and a higher LRG1 expression predicted poor clinical outcomes especially distant metastasis free survival, supporting the role of LRG1 in CRC progression. Collectively, this study provided a novel insight into CAFs-mediated metastasis in CRC and indicated that therapeutic targeting of CAFs-mediated IL-6-STAT3-LRG1 axis might be a potential strategy to mitigate metastasis in CRC.Subject terms: Colon cancer, Cancer microenvironment 相似文献
44.
镉离子诱导BA/F3β细胞发生奇特的细胞凋亡 总被引:2,自引:0,他引:2
细胞凋亡一般都伴随有DNA 片段化, 活性氧含量增加, 并能被过量的Bcl2 所抑制。以BA/F3β细胞为模型, 利用MTT 检测、Hochest 染色以及透射电镜检测等技术却发现, 镉离子虽然可以诱导该细胞凋亡, 但是这种凋亡没有DNA 片段化, 也没有活性氧含量增加。此外, 过量Bcl2 对这种凋亡也没有保护作用。因此, 可以确认镉离子诱导BA/F3β细胞发生了奇特的细胞凋亡。 相似文献
45.
栓皮栎体细胞胚胎发生的细胞组织学观察 总被引:1,自引:0,他引:1
以栓皮栎未成熟合子胚为外植体,在添加0.25mg/L 2,4-D和0.5mg/L 6-BA的MS培养基上6周可诱导产生2种类型的胚性愈伤组织,一种表面具光泽、白色;另一种表面光滑湿润具光泽,色泽淡黄或无色透明。组织切片表明,胚性愈伤组织的细胞体积小,细胞核大,细胞质浓,细胞排列紧密;非胚性愈伤组织细胞的体积大,细胞核小,细胞质稀薄。胚性细胞团培养在不含激素的培养基上可诱导产生体细胞胚。体细胞胚直接起源于胚性细胞团表皮或近表皮的单细胞,经历与合子胚相似的球形胚、心形胚、鱼雷胚和子叶胚发育阶段。所有发育时期的体细胞胚的胚轴、子叶均产生次生体胚,它们起源于细胞质较浓的表皮单细胞。 相似文献
46.
四川大头茶(Gordonia acumenata)是我国亚热带西南地区常绿阔叶林优势种之一,材质好,生长快而又未被人注意的一种优良树种。由于它是喜阳的常绿阔叶顶极先锋种(pioneer climax species)其幼苗耐阴,所以在针阔叶混交林中排挤了先锋树种(pioneer species)马尾松,而本身又在常绿阔叶林演替阶段,被更耐阴的顶极种(climax species)所代替,这是由于顶极种有较高的生态位重叠(niche overiap)和最大的生态位宽度(niche breadth)值。四川大头茶Pn日变化具有双峰曲线型和单峰曲线型两种模式,而年变化有明显的季节现象。光照强度和温度是决定Pn的两个主要生态因子,并具有较高的饱和净光合速率和降低暗呼吸能力使其成为喜阳速生的特性。由于速生,其生物量可达176.62t·ha-1;生产量达10.86t·ha-1。四川大头茶幼苗的蒸腾强度与大气湿度、叶温、光强、相对湿度、叶含水量等参数的变化有密切关系。干旱胁迫使光合速率明显下降,从而影响地上部分的生物生产力,但根/冠比却增加18.18%,这可能是植株对干旱胁迫的一种生态适应对策。四川大头茶各器官的营养元素分配与季节有密切关系,同时与土壤中相应的元素含量也有关。 相似文献
47.
Pei-pei Han Shi-ru Jia Ying Sun Zhi-lei Tan Cheng Zhong Yu-jie Dai Ning Tan Shi-gang Shen 《World journal of microbiology & biotechnology》2014,30(9):2407-2418
The application of antibiotic treatment with assistance of metabolomic approach in axenic isolation of cyanobacterium Nostoc flagelliforme was investigated. Seven antibiotics were tested at 1–100 mg L?1, and order of tolerance of N. flagelliforme cells was obtained as kanamycin > ampicillin, tetracycline > chloromycetin, gentamicin > spectinomycin > streptomycin. Four antibiotics were selected based on differences in antibiotic sensitivity of N. flagelliforme and associated bacteria, and their effects on N. flagelliforme cells including the changes of metabolic activity with antibiotics and the metabolic recovery after removal were assessed by a metabolomic approach based on gas chromatography–mass spectrometry combined with multivariate analysis. The results showed that antibiotic treatment had affected cell metabolism as antibiotics treated cells were metabolically distinct from control cells, but the metabolic activity would be recovered via eliminating antibiotics and the sequence of metabolic recovery time needed was spectinomycin, gentamicin > ampicillin > kanamycin. The procedures of antibiotic treatment have been accordingly optimized as a consecutive treatment starting with spectinomycin, then gentamicin, ampicillin and lastly kanamycin, and proved to be highly effective in eliminating the bacteria as examined by agar plating method and light microscope examination. Our work presented a strategy to obtain axenic culture of N. flagelliforme and provided a method for evaluating and optimizing cyanobacteria purification process through diagnosing target species cellular state. 相似文献
48.
49.
Jianyong Xu Huimei Wu Zhigang Mai Junbo Yi Xianqi Wang Lingyun Li Zhong Huang 《Cell proliferation》2021,54(6)
ObjectivesMyocardial infarction (MI) is the most predominant type of cardiovascular diseases with high mortality and morbidity. Stem cell therapy, especially cardiac progenitor cell therapy, has been proposed as a promising approach for cardiac regeneration and MI treatment. Previously, we have successfully generated cardiac progenitor‐like cells, induced cardiosphere (iCS), via somatic reprogramming. However, the genome integration characteristic of virus‐based reprogramming approach hampered their therapeutic applications due to the risk of tumour formation. In the current study, we aim to establish a safer iCS generation strategy with transgene‐free approaches.Materials and MethodsFour transgene‐free approaches for somatic reprogramming, including episome, minicircle, self‐replicative RNA, and sendai virus, were compared, from the perspective of cardiac progenitor marker expression, iCS formation, and cardiac differentiation. The therapeutic effects were assessed in the mouse model of MI, from the perspective of survival rate, cardiac function, and structural alterations.ResultsThe self‐replicative RNA approach produced more iCS, which had cardiomyocyte differentiation ability and therapeutic effects on the mouse model of MI with comparable levels with endogenous cardiospheres and iCS generated with retrovirus. In addition, the CXCR4 (C‐X‐C chemokine receptor 4) positive subpopulation of iCS derived cells (iCSDC) delivered by intravenous injection was found to have similar therapeutic effects with intramyocardial injection on the mouse model of MI, representing a safer delivery approach.ConclusionThus, the optimized strategy for iCS generation is safer and has more therapeutic potentials. 相似文献