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141.
The current study was designed to explore the role and underlying mechanism of lncRNA taurine up-regulated gene 1 (TUG1) in cardiac hypertrophy. Mice were treated by transverse aortic constriction (TAC) surgery to induce cardiac hypertrophy, and cardiomyocytes were treated by phenylephrine (PE) to induce hypertrophic phenotype. Haematoxylin-eosin (HE), wheat germ agglutinin (WGA) and immunofluorescence (IF) were used to examine morphological alterations. Real-time PCR, Western blots and IF staining were used to detect the expression of RNAs and proteins. Luciferase assay and RNA pull-down assay were used to verify the interaction. It is revealed that TUG1 was up-regulated in the hearts of mice treated by TAC surgery and in PE-induced cardiomyocytes. Functionally, overexpression of TUG1 alleviated cardiac hypertrophy both in vivo and in vitro. Mechanically, TUG1 sponged and sequestered miR-34a to increase the Dickkopf 1 (DKK1) level, which eventually inhibited the activation of Wnt/β-catenin signalling. In conclusion, the current study reported the protective role and regulatory mechanism of TUG1 in cardiac hypertrophy and suggested that TUG1 may serve as a novel molecular target for treating cardiac hypertrophy.  相似文献   
142.
Conditionally replicative adenoviruses (CRAds) were promising approach for solid tumour treatment, but its oncolytic efficiency and toxicity are still not satisfactory for further clinical application. Here, we developed the CAIX promotor (CAIXpromotor)‐controlled CRAd armed with a tumour suppressor absent in melanoma 2 (AIM2) to enhance its oncolytic potency. The CAIXpromotor‐AIM2 adenoviruses (Ad‐CAIXpromotor‐AIM2) could efficiently express E1A and AIM2 in renal cancer cells. Compared with Ad‐CAIXpromotor, Ad‐CAIXpromotor‐AIM2 significantly inhibited cell proliferation and enhanced cell apoptosis and cell killing, thus resulting in the oncolytic efficiency in 786‐O cells or OSRC‐2 cells. To explore the therapeutic effect, various Ads were intratumourally injected into OSRC‐2‐xenograft mice. The tumour growth was remarkably inhibited in Ad‐CAIXpromotor‐AIM2‐treated group as demonstrated by reduced tumour volume and weight with a low toxicity. The inflammasome inhibitor YVAD‐CMK resulted in the reduction of anti‐tumour activity by Ad‐CAIXpromotor‐AIM2 in vitro or in vivo, suggesting that inflammasome activation response was required for the enhanced therapeutic efficiency. Furthermore, lung metastasis of renal cancer mice was also suppressed by Ad‐CAIXpromotor‐AIM2 treatment accompanied by the decreased tumour fossil in lung tissues. These results indicated that the tumour‐specific Ad‐CAIXpromotor‐AIM2 could be applied for human renal cancer therapy. The therapeutic strategy of AIM2‐based CRAds could be a potential and promising approach for the therapy of primary solid or metastasis tumours.  相似文献   
143.
Ginseng and the seed of Zizyphus jujuba var. spinosa, which are traditional Chinese medicinal materials, were often used in ancient Chinese recipes as a pair of medicines. They can replenish the primordial qi and tonify the spleen. This study investigated the effects of ginseng and the seed of Zizyphus jujuba var. spinosa (GS) extract on gut microbiota diversity in rats with spleen deficiency syndrome (SDS). A total of 52 compounds (including 16 flavonoids, 35 saponins, and 1 alkaloid) were identified and analyzed from the GS extract by UPLC‐Q‐Orbitrap‐MS/MS. The GS extract significantly increased the relative abundance of Firmicutes and Bacteroidetes in rats with SDS but decreased that of Proteobacteria and Actinobacteria. At the genus level, the GS extract significantly increased the relative abundance of Lactobacillus and Bifidobacterium in rats with SDS but decreased that of Streptococcus, Escherichia‐Shigella, Veillonella, and Enterococcus. In addition, the GS extract influenced glucose and amino acid metabolism. In summary, the results showed that the GS extract changed the structure and diversity of gut microbiota in rats with SDS and balanced the metabolic process.  相似文献   
144.
The capacitance of microsupercapacitors (MSCs) can double if both sides of substrates are used to construct MSCs. Nevertheless, achieving electric connections of MSCs through substrates is a challenge due to the difficulty in precisely positioning each MSC couple that has two of the same MSCs units on two sides. In this work, taking advantage of the synchronous etching on both sides of transparent polyethylene terephthalate substrates by femtosecond laser pulses, a double‐sided configuration is attained with high precision in the alignment of back‐to‐back MSC couples and versatile double‐side MSCs are realized via arbitrary on‐ and through‐substrate connections of MXene MSC units. The MXene double‐side MSC fabricated by the series connection of 12 spiral pattern MXene MSC units with interdigital electrodes of 10 μm width interspace can output a large working voltage of 7.2 V. Additionally, femtosecond laser etching brings the transformation of MXene into titania near‐etched edges with a lateral distance less than 1 µm. Such a small laser‐affected area has little influence on the capacitive performance, which is one of advantages for femtosecond laser over conventional lasers. This research is valuable for one‐step manufacturing of highly integrated MSCs in the field of miniaturized energy storage systems.  相似文献   
145.
Electrochemical reduction of carbon dioxide (CO2) to fuels and value‐added industrial chemicals is a promising strategy for keeping a healthy balance between energy supply and net carbon emissions. Here, the facile transformation of residual Ni particle catalysts in carbon nanotubes into thermally stable single Ni atoms with a possible NiN3 moiety is reported, surrounded with a porous N‐doped carbon sheath through a one‐step nanoconfined pyrolysis strategy. These structural changes are confirmed by X‐ray absorption fine structure analysis and density functional theory (DFT) calculations. The dispersed Ni single atoms facilitate highly efficient electrocatalytic CO2 reduction at low overpotentials to yield CO, providing a CO faradaic efficiency exceeding 90%, turnover frequency approaching 12 000 h?1, and metal mass activity reaching about 10 600 mA mg?1, outperforming current state‐of‐the‐art single atom catalysts for CO2 reduction to CO. DFT calculations suggest that the Ni@N3 (pyrrolic) site favors *COOH formation with lower free energy than Ni@N4, in addition to exothermic CO desorption, hence enhancing electrocatalytic CO2 conversion. This finding provides a simple, scalable, and promising route for the preparation of low‐cost, abundant, and highly active single atom catalysts, benefiting future practical CO2 electrolysis.  相似文献   
146.
The emodin anthraquinone derivatives are generally used in traditional Chinese medicine due to their various pharmacological activities. In the present study, a series of emodin anthraquinone derivatives have been designed and synthesized, among which 1,3‐dihydroxy‐6,8‐dimethoxyanthracene‐9,10‐dione is a natural compound that has been synthesized for the very first time, and 1,3‐dimethoxy‐5,8‐dimethylanthracene‐9,10‐dione is a compound that has never been reported earlier. Interestingly, while total seven of these compounds showed neuraminidase inhibitory activity in influenza virus with inhibition rate more than 50 %, specific four compounds exhibited significant inhibition of tumor cell proliferation. The further results demonstrate that 1,3‐dimethoxy‐5,8‐dimethylanthracene‐9,10‐dione showed the best anticancer activity among all the synthesized compounds by inducing highest apoptosis rate to HCT116 cancer cells and arresting their G0/G1 cell cycle phase, through elevation of intracellular level of reactive oxygen species (ROS). Moreover, the binding of 1,3‐dimethoxy‐5,8‐dimethylanthracene‐9,10‐dione with BSA protein has thoroughly been investigated. Altogether, this study suggests the neuraminidase inhibitory activity and antitumor potential of the new emodin anthraquinone derivatives.  相似文献   
147.
Carbon dots have been recognized as one of the most promising candidates for the oxygen reduction reaction (ORR) in alkaline media. However, the desired ORR performance in metal–air batteries is often limited by the moderate electrocatalytic activity and the lack of a method to realize good dispersion. To address these issues, herein a biomass‐deriving method is reported to achieve the in situ phosphorus doping (P‐doping) of carbon dots and their simultaneous decoration onto graphene matrix. The resultant product, namely P‐doped carbon dot/graphene (P‐CD/G) nanocomposites, can reach an ultrahigh P‐doping level for carbon nanomaterials. The P‐CD/G nanocomposites are found to exhibit excellent ORR activity, which is highly comparable to the commercial Pt/C catalysts. When used as the cathode materials for a primary liquid Al–air battery, the device shows an impressive power density of 157.3 mW cm?2 (comparing to 151.5 mW cm?2 of a similar Pt/C battery). Finally, an all‐solid‐state flexible Al–air battery is designed and fabricated based on our new nanocomposites. The device exhibits a stable discharge voltage of ≈1.2 V upon different bending states. This study introduces a unique biomass‐derived material system to replace the noble metal catalysts for future portable and wearable electronic devices.  相似文献   
148.
Zeng  Weimin  Li  Fang  Wu  Chenchen  Yu  Runlan  Wu  Xueling  Shen  Li  Liu  Yuandong  Qiu  Guanzhou  Li  Jiaokun 《Bioprocess and biosystems engineering》2020,43(1):153-167

Heavy metal resistant bacteria are of great interest because of their potential use in bioremediation. Understanding the survival and adaptive strategies of these bacteria under heavy metal stress is important for better utilization of these bacteria in remediation. The objective of this study was to investigate the role of bacterial extracellular polymeric substance (EPS) in detoxifying against different heavy metals in Bacillus sp. S3, a new hyper antimony-oxidizing bacterium previously isolated from contaminated mine soils. The results showed that Bacillus sp. S3 is a multi-metal resistant bacterial strain, especially to Sb(III), Cu(II) and Cr(VI). Toxic Cd(II), Cr(VI) and Cu(II) could stimulate the secretion of EPS in Bacillus sp. S3, significantly enhancing the adsorption and detoxification capacity of heavy metals. Both Fourier transform infrared spectroscopy (FTIR) and three-dimensional excitation–emission matrix (3D-EEM) analysis further confirmed that proteins were the main compounds of EPS for metal binding. In contrast, the EPS production was not induced under Sb(III) stress. Furthermore, the TEM–EDX micrograph showed that Bacillus sp. S3 strain preferentially transported the Sb(III) to the inside of the cell rather than adsorbed it on the extracellular surface, indicating intracellular detoxification rather than extracellular EPS precipitation played an important role in microbial resistance towards Sb(III). Together, our study suggests that the toxicity response of EPS to heavy metals is associated with difference in EPS properties, metal types and corresponding environmental conditions, which is likely to contribute to microbial-mediated remediation.

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149.
目的:调查乳腺癌患者改良根治术后生活质量,并对其复发转移的影响因素进行分析。方法:选取2012年6月~2014年6月期间于我院行改良根治术的乳腺癌患者197例,于术后3个月、术后6个月、术后12个月采用乳腺癌患者生命质量测定量表(FACT-B)评价患者生活质量。采用我院自制的调查问卷统计患者基本治疗情况,分析乳腺癌改良根治术后复发转移的影响因素。结果:本研究中,共发放197份问卷调查,回收195份,回收率为98.98%(195/197)。其中195例患者中有73例发生复发转移(复发转移组),122例未发生复发转移(未复发转移组)。195例乳腺癌患者术后3个月、术后6个月、术后12个月社会/家庭状况、生理状况、功能状况、情感状况、附加关注条目、总体生活质量等项目评分呈递增趋势(P0.05)。多因素Logistic回归分析显示,病理类型为浸润性非特殊性癌、肿瘤大小≥2 cm、临床分期为Ⅲ期、激素受体为ER及PR均阴性均是乳腺癌改良根治术后复发转移的独立危险因素(P0.05),而采用放化疗、联合化疗方案、内分泌治疗以及p53蛋白阳性表达是乳腺癌改良根治术后复发转移的独立保护因素(P0.05)。结论:乳腺癌患者行改良根治术后生活质量呈动态变化,其术后复发转移影响因素为病理类型、临床分期、肿瘤大小、激素受体、化疗方案、p53蛋白、内分泌治疗及放化疗。  相似文献   
150.
摘要 目的:总结原发性子宫恶性淋巴瘤的临床表现、影像及病理学特点,以期提高对原发性子宫恶性淋巴瘤的认识及诊治水平。方法:通过PubMed、万方、维普、中国知网数据库检索2001年1月至2019年12月报道的原发性子宫恶性淋巴瘤的文献,结合首都医科大学附属北京妇产医院收治的1例原发性子宫大B细胞淋巴瘤的病例资料,对此类患者临床表现、影像及病理学特点、治疗方案及预后进行总结。结果:患者女,64岁,发现盆腔肿物半月伴有绝经后阴道流血,盆腔CT提示:宫体与宫颈局部巨大团块状软组织密度灶,宫底及宫体上段可见内膜。宫腔镜下组织活检病理:(宫内物)符合低分化恶性肿瘤,结合免疫组化结果,诊断原发性子宫大B细胞淋巴瘤。行开腹全子宫及双侧附件、大网膜及腹膜后淋巴结清扫术,术后接受CHOP方案化疗六程,现治疗后随访17月,未发现复发。结论:原发性子宫恶性淋巴瘤极少见,组织学上以大B 细胞淋巴瘤为主,临床表现缺乏特异性。最终需要结合免疫组化确诊。该疾病恶性程度高,治疗上以根治性手术联合化疗为主,预后较差。  相似文献   
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