DNASE1L3 inhibits proliferation,invasion and metastasis of hepatocellular carcinoma by interacting with β‐catenin to promote its ubiquitin degradation pathway

As a member of the deoxyribonuclease 1 family, DNASE1L3 plays a significant role both inside and outside the cell. However, the role of DNASE1L3 in hepatocellular carcinoma (HCC) and its molecular basis remains to be further investigated. In this study, we report that DNASE1L3 is downregulated in clinical HCC samples and evaluate the relationship between its expression and HCC clinical features. In vivo and in vitro experiments showed that DNASE1L3 negatively regulates the proliferation, invasion and metastasis of HCC cells. Mechanistic studies showed that DNASE1L3 recruits components of the cytoplasmic β‐catenin destruction complex (GSK‐3β and Axin), promotes the ubiquitination degradation of β‐catenin, and inhibits its nuclear transfer, thus, decreasing c‐Myc, P21 and P27 level. Ultimately, cell cycle and EMT signals are restrained. In general, this study provides new insight into the mechanism for HCC and suggests that DNASE1L3 can become a considerable target for HCC.

Decreased expression of DNASE1L3 is associated with poor prognosis in patients with HCC DNASE1L3 inhibits the proliferation and cell cycle of HCC cells in vitro and promotes the invasion and metastasis of HCC cells DNASE1L3 inhibits the tumorigenicity and metastasis of HCC cells in vivo DNASE1L3 interacts with β‐catenin and promotes its binding to the β‐catenin destroying complex DNASE1L3 interacts with P21 and stabilizes P21 by mediating the deubiquitin activity     

Effects of highly selective sensory/motor nerve injury on bone metabolism and bone remodeling in rats

Objectives:This work aimed to investigate the mechanism of selective sensory/motor nerve injury in affecting bone metabolism and remodeling.Methods:The selective sensory/motor nerve injury rat model was constructed through posterior rhizotomy (PRG), anterior rhizotomy (ARG), or anterior combined with posterior rhizotomy (APRG) at the L_4-6 sensory/motor nerves on the right side of rats. Sham-operated (SOG) rats served as control. At 8 weeks after surgery, the sciatic nerves, spinal cord segments L₅ and tibial tissues were collected for analysis.Results:the integrity of trabecular bone was damaged, the number of trabecular bone was decreased and the number of osteoclasts were increased in ARG group. ARG activated NF-κβ and PPAR-γ pathways, and inhibited Wnt/β-catenin pathway. ARG group exhibited high turnover bone metabolism. In PRG group, the trabecular bone morphology became thinner, and the number of osteoclasts was increased. NF-κβ pathway was activated and OPG/RANKL ratio was decreased in PRG group. The activated osteoclasts, reduced osteoblasts activity and lower turnover bone metabolism were observed in PRG group. Additionally, the bone metabolism in APRG group was similar to ARG group.Conclusion:The posterior rhizotomy and anterior rhizotomy induced the different degree of osteoporosis in rats, which may attribute to regulate Wnt/β-catenin, NF-κβ and PPAR-γ signalling pathways.     

Downstream bioprocessing of human pluripotent stem cell‐derived therapeutics

With the advancement in lineage‐specific differentiation from human pluripotent stem cells (hPSCs), downstream cell separation has now become a critical step to produce hPSC‐derived products. Since differentiation procedures usually result in a heterogeneous cell population, cell separation needs to be performed either to enrich the desired cell population or remove the undesired cell population. This article summarizes recent advances in separation processes for hPSC‐derived cells, including the standard separation technologies, such as magnetic‐activated cell sorting, as well as the novel separation strategies, such as those based on adhesion strength and metabolic flux. Specifically, the downstream bioprocessing flow and the identification of surface markers for various cell lineages are discussed. While challenges remain for large‐scale downstream bioprocessing of hPSC‐derived cells, the rational quality‐by‐design approach should be implemented to enhance the understanding of the relationship between process and the product and to ensure the safety of the produced cells.     

黄河三角洲河滩与潮滩芦苇对盐胁迫的生理生态响应

研究黄河三角洲两种生境芦苇对盐胁迫的生理生态响应差异,能为退化滨海湿地生态修复中芦苇植株来源的选择提供重要的理论支持。在盐胁迫(300 mmol/L NaCl)下,比较研究了黄河三角洲河滩芦苇(低盐生境)和潮滩芦苇(高盐生境)叶片中的Na⁺含量、根部分生区Na⁺流速、叶片的光合作用参数、H₂O₂的含量、抗氧化酶的活性、丙二醛和脯氨酸的含量。结果表明:盐胁迫显著提高了河滩芦苇叶片中Na⁺含量,但对潮滩芦苇叶片Na⁺影响不显著。进一步通过非损伤微测技术研究发现,盐胁迫后,潮滩芦苇比河滩芦苇的根部分生区的Na⁺外排流速更高(潮滩芦苇:(1982.05±122.74) pmol cm^-2 s^-1vs.(87.93±12.94) pmol cm^-2 s^-1,P<0.01;河滩芦苇:(1574.16±458.90) pmol cm^-2     

雪灾干扰后林冠开阔度对黄心树幼苗更新的影响

幼苗更新是森林更新的关键过程,而林窗对于植物幼苗更新、生长及最终存活具有重要影响。极端气候事件会使森林在短时间内形成大量林窗,从而显著影响林内幼苗更新和存活。本研究以2015年雪灾后云南省哀牢山中山湿性常绿阔叶林优势种黄心树(Machilus bombycina)幼苗为对象,对194个1 m×1 m样方中的幼苗生长和死亡动态进行为期4年的监测,利用线性混合模型(LMM)和广义线性混合模型(GLMM),分析林冠开阔度对幼苗高度相对生长率、叶片相对增长率、新增率和死亡率的影响,研究了雪灾干扰后的林冠开阔度对植物幼苗更新的影响。结果表明:(1)林冠开阔度随时间推移逐渐变小(20.07%～9.97%),且速度由快到慢;(2) 2015—2016年,已有幼苗高度相对生长率与林冠开阔度呈显著正相关(P<0.05),其余年份两者间无显著相关性; 2016—2017年已有幼苗叶片相对增长率与林冠开阔度呈显著正相关(P<0.05),其余年份两者间无显著相关性;(3)林冠开阔度与幼苗新增率和死亡率均无显著相关性。本研究表明,雪灾后造成的林冠开阔度增加有利于黄心树幼苗生长。     

应用稳定同位素测定贵州凤冈麻湾洞洞穴陆生动物的食物来源及营养级

以贵州凤冈麻湾洞洞穴生态系统为研究对象,运用δ¹³C、δ¹⁵N测定了洞穴动物及其有机碳源的同位素比值,分析了洞穴生态系统的营养级关系及洞穴动物食源。结果表明:洞内植物δ¹³C范围为-41. 78‰～-38. 80‰,较洞外植物低;δ¹⁵N范围为-1. 31‰～1.23‰,在洞外陆源有机质δ¹⁵N范围内;洞穴土壤有机质的δ¹³C范围为-31. 09‰～-24.95‰,δ¹⁵N范围为-1.08‰～7.72‰;洞穴动物δ¹³C范围为-30.41‰～-12.02‰,δ¹⁵N范围为2.07‰～8.94‰;洞穴土壤有机质对动物的食源贡献率超过72%,远高于植物对动物的食源贡献率,即洞穴土壤有机质是洞穴动物的主要食物来源。麻湾洞生态系统主要由4个营养层次组成:植物为第一营养层次;闪夜蛾、螺类、马陆类处于第二营养层次;裸灶螽、长头地蜈蚣处于第三营养层次;蜘蛛类处于第三或第四营养层次。即大部分同种(或同类群)...