Bands of Fontana are caused exclusively by the sinusoidal path of axons in peripheral nerves and predict axon path; evidence from rodent nerves and physical models

The precise cause of the bands of Fontana, striations on peripheral nerves visible to the naked eye, has been the subject of debate for hundreds of years. Some researchers have described them as reflecting the sinuous course of nerve fibres passing through nerves, and others have proposed that endoneurial collagen and sheaths surrounding nerves play a role in their appearance. We hypothesised that the bands are caused exclusively by reflection of light from the surfaces of nerve fibres travelling in phase in sinusoidal waveforms through peripheral nerves. We aligned images of obliquely illuminated nerves with confocal images of axons in those nerves, and the numbers and positions of the bands precisely matched the axonal waves. We also developed three‐dimensional models of nerves with representations of the sinusoidal path of axons at their surface. We observed patterns resembling the bands of Fontana when these models were obliquely illuminated. This provides evidence that the bands of Fontana can be caused by light reflected sinusoidal path of axons alone. We subsequently describe a mechanism of band production based on our observations of both nerves and models. We report that smaller diameter nerves such as phrenic nerves and distal branches of sciatic nerves have shorter band intervals than larger nerves, such as proximal trunks of sciatic nerves, and that shorter band intervals correlate with longer axons per unit length of nerve, which suggests a greater tolerance to stretch. Inspection of banding patterns on peripheral nerves may permit prediction of axon length within nerves, and assist in the interpretation of nerve conduction data, especially in diseases where axon path has become altered.     

基于生物信息学筛选早发性乳腺癌差异表达基因

目的筛选并分析与早发性乳腺癌发生、发展相关的靶基因。 方法(1)在美国国立生物技术信息中心的公共基因芯片数据库(GEO)中检索早发性乳腺癌样本及非早发性乳腺癌样本相关基因芯片数据。对上述数据使用GEO2R、R4.1.2及Venn软件筛选出相关差异表达基因(DEGs)，并运用在线分析工具(Web Gestalt)对DEGs，进行相关功能和信号通路富集分析。(2)同时，通过String在线数据库构建DEGs编码的蛋白质-蛋白质相互作用(PPI)网络，并利用Cytohubba插件对该网络中的基因进行评分，筛选出枢纽基因。将枢纽基因导入Kaplan-Meier生存分析工具(Kaplan-Meier Plotter)，评估枢纽基因在早发性乳腺癌的预后价值。(3)将肿瘤基因组图谱(TCGA)数据库中的肿瘤组织以年龄为标准进行分组，分析枢纽基因在各年龄组中的表达，并与正常组织中的表达进行比较，对得到的枢纽基因进行验证。DEGs表达量的多组间比较使用Kruskal-Wallis H检验，使用Bonferroni法进行两两比较。 结果(1)筛选出编号为GSE89116、GSE109169、GSE36295的基因芯片数据集，共得到80个差异表达基因，其中上调差异表达基因17个，下调差异表达基因63个。富集分析显示：DEGs主要富集在脂质代谢和氧化还原过程以及PPAR信号通路、AMPK信号通路上。(2)在PPI中发现主要的关键基因为PPARG、ADIPOQ、LIPE、PCK1、PDK4、ACACB、PLIN1、CAV1、CD36、ANGPTL4。ACACB、ADIPOQ、CAV1、LIPE、PLIN1、PPARG基因的低表达与乳腺癌患者的不良OS相关(HR＝0.69、0.84、0.76、0.88、0.78、0.82；95%CI：0.59~0.80、0.76~0.93、0.67~0.83、0.79~0.97、0.70~0.86、0.73~0.90；P均<0.050)。(3)ACACB、ADIPOQ、LIPE、PLIN1、CAV1及PPARG这6个与预后相关的基因在正常组织中的表达量均远高于各年龄组肿瘤组织中的表达量(χ²＝104.03、179.57、161.85、189.87、118.56、103.62，P均<0.001)，早发性乳腺癌组(21~40岁)的LIPE、PLIN1表达量低于41~60岁、61~80岁年龄组，差异具有统计学意义(LIPE: Z＝21.07、23.12, P均<0.050; PLIN1：Z＝16.89、18.76, P均<0.050)。 结论早发性乳腺癌与非早发性乳腺癌存在差异基因表达谱，LIPE、PLIN1可能是早发性乳腺癌发生、发展的关键基因。     

序贯HFNC对中老年患者全麻胆囊切除术后低氧血症与再插管率的影响

目的探讨拔除气管插管后序贯经鼻高流量氧疗（HFNC）对中老年患者全麻胆囊切除术后低氧血症和再插管率的影响。 方法采用前瞻性随机对照研究，选取2019年1月至12月新疆维吾尔自治区第三人民医院重症医学科收治的全麻下行胆囊切除术患者90例，将其随机分为HFNC组（30例）、鼻导管组（30例）、面罩组（30例）。比较拔除气管插管前后各组间心率（HR）、血压和血气分析指标［动脉血氧分压（PaO₂）、动脉血二氧化碳分压（PaCO₂）、氧合指数］，以及拔管后患者不适感和再插管率情况。 结果拔除气管插管前，3组患者间HR、收缩压（SBP）、PaO₂、PaCO₂、氧合指数比较，差异无统计学意义（P＞0.05）。拔管后1 h，3组患者间HR和SBP比较，差异无统计学意义（P＞0.05）；HFNC组患者的PaO₂与氧合指数均高于面罩组，PaCO₂低于面罩组，差异均有统计学意义（P=0.013，P=0.009，P=0.031），但与鼻导管组比较，差异均无统计学意义（P=0.106，P=0.101，P=0.545）；面罩组与鼻导管组相比，PaO₂和氧合指数差异均无统计学意义（P=0.363，P=0.314）。鼻导管组黏膜干燥抱怨所占比例最高，面罩组的幽闭恐惧和恶心呕吐所占比例最高，差异均有统计学意义（P＜0.05）。3组患者再插管率比较，差异无统计学意义（P=0.484）。 结论对于中老年全麻下行胆囊切除术后低氧血症的患者而言，相比面罩氧疗，拔除气管插管后采用序贯HFNC可以更好地改善患者的PaO₂、PaCO₂、氧合指数和不适感，但不能降低再插管率。     

利用转录组测序生物信息学初步探讨热射病预后关键基因

目的分析热射病患者外周血单个核细胞转录组测序生物信息学结果,寻找影响热射病预后的关键基因。方法选取2019-06-01~2020-08-30空军军医大学附属西京医院急诊科收治的热射病患者,按照预后分为生存组和死亡组。随机数字法在两组中分别选取患者进行外周血单个核细胞转录组测序,生物信息学分析寻找差异基因;RT-PCR验证筛选出的差异基因在生存组和死亡组中的表达。结果29例诊断为热射病患者入选,按照预后分为生存组和死亡组,其中生存组18例,死亡组11例。随机数字法选取6例生存患者和4例死亡患者,外周血单个核细胞进行转录组测序,两组患者有693个基因表达有明显差异,通过生物信息学分析筛选出趋化因子(C-C基元)配体5(CCL5)、基质金属蛋白酶8(MMP8)、MMP9基因可能与预后相关。将两组外周血单个核细胞的目标基因表达情况通过RT-PCR法表达检测,与生存组比较,死亡组MMP8基因(P=0.8955)和MMP9基因(P=0.0597)表达无明显变化,CCL5基因表达明显上升(t=7.056,P<0.05)。结论CCL5基因可能是影响热射病预后的关键基因,需要进一步深入研究。     

LY3214996 relieves acquired resistance to sorafenib in hepatocellular carcinoma cells

Background: Sorafenib, an oral multi-kinase inhibitor of rapidly accelerated fibrosarcoma; vascular endothelial growth factor receptor-2/3, platelet-derived growth factor receptor, c-Kit, and Flt-3 signaling, is approved for treatment of advanced hepatocellular carcinoma (HCC). However, the benefit of sorafenib is often diminished because of acquired resistance through the reactivation of ERK signaling in sorafenib-resistant HCC cells. In this work, we investigated whether adding LY3214996, a selective ERK1/2 inhibitor, to sorafenib would increase the anti-tumor effectiveness of sorafenib to HCC cells.Methods: The Huh7 cell line was used as a cell model for treatment with sorafenib, LY3214996, and their combination. Phosphorylation of the key kinases in the Ras/Raf/MAPK and PI3K/Akt pathways, protein expression of the cell cycle, and apoptosis migration were assessed with western blot. MTT and colony-formation assays were used to evaluate cell proliferation. Wound-healing assay was used to assess cell migration. Cell cycle and apoptosis analyses were conducted with flow cytometry.Results: LY3214996 decreased phosphorylation of the Ras/Raf/MAPK and PI3K/Akt pathways, including p-c-Raf, p-P90RSK, p-S6K and p-eIF4EBP1 activated by sorafenib, despite increased p-ERK1/2 levels. LY3214996 increased the anti-proliferation, anti-migration, cell-cycle progression, and pro-apoptotic effects of sorafenib on Huh7^R cells.Conclusions: Reactivation of ERK1/2 appears to be a molecular mechanism of acquired resistance of HCC to sorafenib. LY3214996 combined with sorafenib enhanced the anti-tumor effects of sorafenib in HCC. These findings form a theoretical basis for trial of LY3214996 combined with sorafenib as second-line treatment of sorafenib-resistant in advanced HCC.     

真实世界中丹参川芎嗪注射液治疗冠状动脉硬化性心脏病联合用药复杂网络分析＊

目的 本研究为探究丹参川芎嗪注射液治疗冠状动脉硬化性心脏病联合用药优效方案。通过全国19家三甲医院信息系统（hospital information system，HIS）数据库中优效人群联合用药规律探讨冠心病治疗中丹参川芎嗪联合用药方案。方法 全国19家三甲医院4952例患者纳入分析，采用真实世界研究方法及Tabu搜索算法。结果 丹参川芎嗪注射液 + 单硝酸异山梨酯 + 速效救心丸 + 阿卡波糖 + 蛋白水解物，为冠心病中西医联合用药频次最高组合，适宜冠心病心绞痛合并糖尿病及缺血性脑血管疾病患者；丹参川芎嗪注射液 + 维生素复方 + 蛋白水解物 + 硝酸甘油 + 头孢类 + 阿卡波糖为最常见西药搭配，用于冠心病合并消化性溃疡、失眠、炎症及糖尿病；活血化瘀制剂（化瘀通脉剂） + 益气养阴剂 + 清热类中药为使用频率最高组合用于冠心病血瘀证合并气阴两虚或阴虚火旺证。结论 目前临床治疗冠心病越来越关注全身治疗，符合中医整体观念及治未病原则。丹参川芎嗪注射液治疗冠心病联合用药符合最新的冠心病诊疗指南。