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191.
192.
Zejing Wang Hao Lu Tao Tang Lei Liu Bohan Pan Jiqiu Chen Dasheng Cheng Xiaoxiao Cai Yu Sun Feng Zhu Shihui Zhu 《Cell proliferation》2022,55(11)
ObjectivesTo determine the therapeutic effect of tetrahedral framework nucleic acids (tFNAs) on diabetic wound healing and the underlying mechanism.Materials and MethodsThe tFNAs were characterized by polyacrylamide gel electrophoresis (PAGE), atomic force microscopy (AFM), transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential assays. Cell Counting Kit‐8 (CCK‐8) and migration assays were performed to evaluate the effects of tFNAs on cellular proliferation and migration. Quantitative polymerase chain reaction (Q‐PCR) and enzyme‐linked immunosorbent assay (ELISA) were used to detect the effect of tFNAs on growth factors. The function and role of tFNAs in diabetic wound healing were investigated using diabetic wound models, histological analyses and western blotting.ResultsCellular proliferation and migration were enhanced after treatment with tFNAs in a high‐glucose environment. The expression of growth factors was also facilitated by tFNAs in vitro. During in vivo experiments, tFNAs accelerated the healing process in diabetic wounds and promoted the regeneration of the epidermis, capillaries and collagen. Moreover, tFNAs increased the secretion of growth factors and activated the Wnt pathway in diabetic wounds.ConclusionsThis study indicates that tFNAs can accelerate diabetic wound healing and have potential for the treatment of diabetic wounds.Tetrahedral framework nucleic acids (tFNAs) can facilitate the proliferation and migration of HaCaTs, HDFs and HUVECs in a high‐glucose environment. tFNAs can accelerate diabetic wound healing by promoting epithelialization, vascularization, collagen synthesis and the secretion of growth factors via the Wnt pathway. 相似文献
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Qiaoyu Chen Yanyan Hu Lijun Yang Benguo Zhu Feng Luo 《Current issues in molecular biology》2022,44(9):4070
Phosphorus treatment can reduce Cd accumulation and Cd toxicity in rice, but alterations in the internal regulatory network of rice during this process have rarely been reported. We have removed the effect of cadmium phosphate precipitation from the hydroponic system, treated a pair of different Cd-response rice varieties with different levels of phosphorus and cadmium and examined the changes in physiological indicators and regulatory networks. The results demonstrated that phosphorus treatment significantly reduced Cd accumulation in both types of rice, although the antioxidant systems within the two types of rice produced opposite responses. Overall, 3 mM phosphorus treatment to Cd-N decreased the expression of OsIAA17 and OsACO1 by 32% and 37%, respectively, while increasing the expression of OsNR2 by 83%; these three genes regulate the synthesis of auxin, ethylene, and nitric oxide in rice. IAA and NO levels in rice shoots increased by 24% and 96%, respectively, and these changes contribute to Cd detoxification. The cadmium transporter genes OsHMA2, OsIRT1, and OsABCC1 were significantly down-regulated in Cd-N roots after triple phosphorus treatment. These data suggest that phosphorus treatment can reduce Cd accumulation and enhance Cd resistance in rice by affecting the expression of signaling molecules. 相似文献
196.
Multimodal communication in animals is common, and is particularly well studied in signals that include both visual and auditory components. Multimodal signals that combine acoustic and olfactory components are less well known. Multimodal communication plays a crucial role in agonistic interactions in many mammals, but relatively little is known about this type of communication in nocturnal mammals. Here, we used male Great Himalayan leaf-nosed bats Hipposideros armiger to investigate multimodal signal function in acoustic and olfactory aggressive displays. We monitored the physiological responses (heart rate [HR]) when H. armiger was presented with 1 of 3 stimuli: territorial calls, forehead gland odors, and bimodal signals (calls + odors). Results showed that H. armiger rapidly increased their HR when exposed to any of the 3 stimuli. However, the duration of elevated HR and magnitude of change in HR increased significantly more when acoustic stimuli were presented alone compared with the presentation of olfactory stimuli alone. In contrast, the duration of elevated HR and magnitude of change in HR were significantly higher with bimodal stimuli than with olfactory stimuli alone, but no significant differences were found between the HR response to acoustic and bimodal stimuli. Our previous work showed that acoustic and chemical signals provided different types of information; here we describe experiments investigating the responses to those signals. These results suggest that olfactory and acoustic signals are non-redundant signal components, and that the acoustic component is the dominant modality in male H. armiger, at least as it related to HR. This study provides the first evidence that acoustic signals dominate over olfactory signals during agonistic interactions in a nocturnal mammal. 相似文献
197.
Due to the overexploitation of farming, as well as habitat destruction, the wild population of Chinese giant salamander (CGS) Andrias davidianus, a species with seven genetically distinct lineages, has decreased by over 80% in the past 70 years. Traditional survey methods have proven to be unsuitable for finding this rare and elusive species. We evaluated the efficacy of environmental DNA (eDNA) sampling to detect CGS indirectly from its aquatic environment. We developed several species-specific primer sets; validated their specificity and sensitivity; and assessed their utility in silico, in the laboratory, and at two field sites harboring released farm-bred CGS. We detected the presence of CGS DNA by using polymerase chain reaction and Sanger sequencing. We also sequenced an amplicon mixture of seven haplotype-represented samples using high-throughput sequencing. Our eDNA methods could detect the presence of CGS at moderate densities reported across its range, proving them as a cost-effective way to establish broad-scale patterns of occupancy for CGS. In addition, our primers enabled the detection of mitochondrial lineage mixture or introduced individuals from geographically isolated populations of CGS. 相似文献
198.
翅多型现象是昆虫非遗传多型性的一种表现,包括不具飞行能力的短翅型或无翅型,以及可以进行长距离迁飞的长翅型或有翅型。翅多型现象常发生在可以携带病原并将其传播给植物宿主的媒介昆虫中,对植物病害的时空分布与暴发有重要影响。本文从翅型分化的遗传规律、诱导因素、分子机制和伴随翅型分化的其他生理表现4个方面,对植物病原主要传播媒介蚜虫和飞虱的翅型分化研究进行综述和梳理。昆虫翅型分化的诱导因素主要包括温度、湿度和光周期等非生物因素以及虫口密度、宿主营养、病毒等生物因素;而其内在的分子机制大多是通过胰岛素/胰岛素样生长因子信号(IIS)通路、c-Jun氨基末端激酶(c-Jun NH2-terminal kinase, JNK)信号通路、Wingless和嗅觉受体SaveOrco等调控。翅型分化的同时伴随着生理状态的变化,表现为短翅型具有更强的繁殖能力和长翅型含有更丰富的飞行肌结构成分。目前,昆虫翅型分化的研究尚不够完善,有许多需要解答的问题,如找到胰岛素/胰岛素样生长因子信号通路中真正发挥功能的靶基因,JNK如何调控翅型分化以及虫媒病毒影响媒介昆虫翅型的分子机理。本综述可为控制虫... 相似文献
199.
黄河三角洲河滩与潮滩芦苇对盐胁迫的生理生态响应 总被引:1,自引:0,他引:1
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 相似文献
200.
长江口崇明东滩盐沼湿地围堤工程是以清除入侵植物互花米草为目的而进行的生态修复工程。由于大型底栖动物可作为重要的环境指示生物,分析比较了围堤前后围堤工程内和工程外大型底栖动物群落结构及多样性的变化。结果表明,在2013年围堤工程前和2016年围堤工程后两次调查共采集到大型底栖动物29种,分别隶属于无针纲、多毛纲、腹足纲、双壳纲、甲壳纲和昆虫纲。在2013和2016年围堤外光滩生境分别采集到底栖动物21种和27种,并且所有样线都表现出物种数量增加或持平;然而在围堤内区域,两条全封闭样线(样线2和样线3)由围堤前的12种减少到围堤后的6种,而在保留进出水口的半封闭样线1围堤内由围堤前7种增加到围堤后12种。底栖动物平均密度在半封闭样线1围堤内由围堤前的(75±0)个/m2增加到围堤后的(288±111)个/m2(P=0.091),在全封闭的样线2(2013:(120±17)个/m2; 2016:(7±7)个/m2)和样线3(2013:(359±20)个/m2; 2016:(93±93... 相似文献