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Polyethylene oxide (PEO)-polypropylene oxide (PPO)-polyethylene oxide block copolymer having different molecular weights are used as precursors of carbon materials to prepare Hollow -Derivatives carbon material as an electrocatalyst through block copolymer self-assembly. The composition and microstructure of the prepared catalysts are shown by Raman spectroscopy, X-ray diffraction (XRD), Test of nitrogen adsorption and desorption curves, High resolution transmission electron microscopy (HR-TEM) and scanning electron microscopy (HR-SEM). Oxygen was passed into alkaline electrolyte solution until the solution reached saturation state. With molecular weight increasing, the obtained sample gradually changed from block to hollow and spherical. When the molecular weight was 12600 g mol−1, the evenly hollow carbon nanocages was acquired (C-12600). In O2 saturated alkaline electrolyte (0.1 M KOH solution), C-12600's limited current density，half-wave potential and initial potential are 5.23 mA cm−2@0.4 V, 0.72 V and 0.81 V, respectively. And most important is that half-wave potential and onset potential have barely change after 2000 cycles of cyclic voltammetry. As a result, the porous carbon materials exhibited excellent electrocatalytic activity while maintaining high stability in alkaline KOH solution.

In this work, lithium titanate (Li4Ti5O12)/N-doped carbon/stainless steel mesh (LTO/N-C/SSM) flexible electrodes for Li-ion capacitors were successfully prepared without binder via a facile method ...

Rui Chen,1 Xi Wang,2,3 Shixian Zhou,2,4 Zongyue Zeng2 1Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, People’s Republic of China; 2Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, People’s Republic of China; 3Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, 400016, People’s Republic of China; 4Department of Pathology, Central Hospital of Jiangjin District, Chongqing, 402260, People’s Republic of ChinaCorrespondence: Zongyue ZengDepartment of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing, 400016, People’s Republic of ChinaTel +86 23-8895-5532Email zengzongyue@126.comIntroduction: Growing evidence suggests that long non-coding RNAs (lncRNAs), such as lncRNA HOXA-AS2, are critical regulators involved in human cancer. However, the biological functions and detailed mechanisms underlying how lncRNA HOXA-AS2 affects oral squamous cell carcinoma (OSCC) remain unexplored.Methods: The expression of lncRNA HOXA-AS2 and miR-567 was determined in OSCC cell lines and clinical tissues by quantitative real-time PCR (qRT-PCR). Target site prediction and luciferase report assays were used to explore their potential interaction and binding sites between lncRNA HOXA-AS2 and miR-567. Overexpression or silencing expression of lncRNA HOXA-AS2 was performed to confirm that miR-567 was suppressed by lncRNA HOXA-AS2. WST-1 assay, crystal staining assay, and cell cycle analysis were used to assess the cell viability and proliferation ability. The target gene of miR-567 was predicted by Targetscan and validated by luciferase report assay as well as qRT-PCR and Western Blot. Xenograft nude mice model was done to demonstrate that lncRNA HOXA-AS2 promoted cell proliferation via targeting miR-567/CDK8 in vivo.Results: LncRNA HOXA-AS2 was up-regulated in OSCC cells and tissues with the expression of miR-567 decreased. The tissue lncRNA HOXA-AS2 expression was found to positively correlate with the TNM stage and lymph node metastasis of OSCC patients. In terms of the mechanism, we found that lncRNA HOXA-AS2 negatively regulates miR-567 expression via a direct interaction. Functionally, overexpression of lncRNA HOXA-AS2 significantly promoted OSCC cell proliferation, while knockdown of lncRNA HOXA-AS2 significantly inhibited it. We also observed that miR-567 directly targets the 3ʹ UTR of CDK8. Moreover, silencing lncRNA HOXA-AS2 inhibited tumor growth with the expression of miR-567 increased and CDK8 decreased in vivo.Conclusion: LncRNA HOXA-AS2 was up-regulated in OSCC, and its up-regulation correlated with poor clinical outcomes. The lncRNA also promoted OSCC cell proliferation by directly binding to miR-567, leading to an increase in CDK8 expression. The potential prognostic value of lncRNA HOXA-AS2 should be explored in future studies.Keywords: LncRNA HOXA-AS2, MiR-567, CDK8, Oral squamous cell carcinoma, Tumor progression

In order to reduce the cost of oxygen reduction reaction (ORR) catalyst in fuel cell, polyethylene oxide-polypropylene oxide-polyethylene oxide (PEO-PPO-PEO) three-block copolymer (F127) and Zn(OH)2 were used as carbon resource and morphology retaining agent to prepare porous nanocages for ORR catalyst in alkaline solution. Its composition and microstructure were characterized by X-ray diffraction Raman spectroscopy (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) method. Electrochemical properties were evaluated in O2 saturated alkaline solution. Results showed the sample obtained at 700 °C (C-700) was composed of porous carbon nanocages with diameter of 50 nm and shell thickness of 4 nm. C-700 had the maximum surface area (1011 m2 g−1) and the best ORR catalytic performance. The main reason is that polypropylene oxide (PPO) group at the lipophilic end begins to decompose at 500 °C, and the polyethylene oxide (PEO) group at the lipophilic end at 700 °C decomposes completely. In O2 saturated 0.1 M KOH solution, C-700's oneset potential, limit current density and half-wave potential, which were 0.89 V, 5.59 mA/cm2@0.45 V and 0.71 V, respectively, were close to that of commercial 20% Pt/C catalyst. It was noted that the oneset potential and half-wave potential of C-700 had barely change, and limit current density attenuated about 87.8% after 2000 CV cycle. The obtained catalyst behaved good catalytic activity and stability for ORR in alkaline solution and a potential application prospect in fuel cells.

A novel nanoblocks@nanoballs NiMnO3/Ni6MnO8 electrode material was synthesized by one-step solvothermal–hydrothermal method, followed by thermal annealing. At the same time, electrode materials with different nanostructure were prepared by changing the volume ratio of deionied water and ethylene glycol. The results show that different structure has been gained including nanospheres, nanosheets and nanoblocks. When the deionied water: ethylene glycol = 1:1 (nanoblocks@nanoballs NiMnO3/Ni6MnO8 composite structure), the electrode material has a maximum specific surface area of 55.3 m2 g−1. The electrode material exhibited outstanding electrochemical performance with specific capacitance reached 494.4 F g−1 at a current density of 1 A g−1 as well as superior cycling performance of 88.0% capacitance retention after 5000 cycles at 3 A g−1. Such excellent performance was due to the synergistic effective between the Ni6MnO8 nanoballs and NiMnO3 nanoblocks. Nanoballs structure will increase in specific surface area and redox reaction active sites, and the blocks structure acts as a holder to improved the cycle performance. The NiMnO3/Ni6MnO8 become a promising candidate as next-generation electrode material for high-performance supercapacitors.

Due to the short length and differences in abundance of microRNAs, microRNA profile screening and quantification is challenging. In this study, we found that size selection magnetic beads could be employed to easily and efficiently remove long RNA transcripts. After removing the long transcripts, the remaining small RNAs could be concentrated and then reverse-transcribed using universal stem-loop primers (USLP), with six randomized nucleotides at the 3' end region. The efficiency of reverse transcription decreased when the number of randomized nucleotides was reduced. In addition, we found that touchdown qPCR improved microRNA profile detection, with lower CT values and better detection efficiency than the regular qPCR protocol, especially for those low-abundance microRNAs. Finally, we incorporated these observations to create a new protocol we named long transcripts minus touchdown qPCR (LTMT-qPCR). We performed a side-by-side comparison of LTMT with USLP and traditional stem-loop primer (TSLP) protocols. We found that LTMT has higher detection efficiency than USLP, especially for the detection of low-abundance microRNAs. Although LTMT was equivalent to TSLP in terms of microRNA profile detection, LTMT is more convenient, user-friendly, and cost-effective. Taken together, the present data indicate that LTMT is a simple, rapid, and user-friendly approach that has higher precision, accuracy, and sensitivity than the previously described methods, making it more suitable for microRNA profile screening and quantification.

Growing evidence shows that long non-coding RNAs (lncRNAs), such as lncRNA HOXA-AS2, have emerged as critical regulators in human cancer. However, the biological function and detail regulating mechanisms that how lncRNA HOXA-AS2 played in oral squamous cell carcinoma (OSCC) remains unexplored. In this study, high expression of lncRNA HOXA-AS2 was determined in OSCC cell lines and clinical tissues, which positively correlated with advanced TNM stage and poor survival of OSCC patients. In mechanism, we found that lncRNA HOXA-AS2 negatively regulated miR-567 expression by direct interaction. Additionally, we also found that the expression of miR-567 inversely decreased in OSCC tissues along with the up-regulation of lncRNA HOXA-AS2. Functionally, overexpression of lncRNA HOXA-AS2 significantly promoted OSCC cell proliferation, while knockdown of lncRNA HOXA-AS2 significantly inhibited it. Additionally, we determined that miR-567 targeted to CDK8 directly at the 3’ UTR. In conclusion, lncRNA HOXA-AS2 was up-rugulated in OSCC, correlated with poor clinical outcomes, and promoted OSCC cell proliferation via sponging miR-567 to promote CDK8 expression. Therefore, the potential prognostic value of lncRNA HOXA-AS2 could be explored further.

In our work, a Ni6MnO8/NiMnO3 composite, which are porous cuboids coated with porous spheres to form a 3D hierarchical structure, is successfully fabricated using a one-step solvothermal method. As an electrode material, this composite possesses high specific capacitance (291.9F/g at 1 A/g) and excellent rate capability (77.2% of specific capacitance maintained at 10 A/g). The specific capacitance retention is 83.4% after 5000 charge/discharge cycles at a current density of 3 A/g. The enhanced performance is mainly attributed to the synergistic effect of Ni6MnO8 and NiMnO3, which can provide more active sites for redox reaction and contribute to electrolyte ion transport. Results demostrate that the Ni6MnO8/NiMnO3 composite as an electrode material in supercapacitors exhibits outstanding electrochemical performance and potential for various applications.

In order to reduce the cost of the catalysts for the anion exchange membrane fuel cell (AEMFC), phosphorus-doped XC-72 carbon catalyst was prepared by one-step carbonization using XC-72 carbon and triphenyl phosphorus (TPP) as carbon source and phosphorus source. The structure, morphology and electrochemical performance of the phosphorus-doped carbon catalyst were evaluated by physical characterization and electrochemical methods. When the proportion of triphenyl phosphorus and XC-72 is 1:5, and carbonization temperature is [Formula: see text], the obtained catalyst shows mesoporous structure formed by the accumulation of nanospheres and exhibits better electrochemical performance, including more positive onset potential (−0.12 V), the largest current density [Formula: see text], which is slightly equal to commercial 20%Pt/C [Formula: see text]. Moreover, P is doped in carbon with C–P and O–P bond, which provide active sites to improve electrochemical performance. Low cost precursor and facile preparation of P-doped C is a candidate for full cell catalyst.

Ovary grafting is not only a method of investigating follicle and oocyte development, but also a useful model to explore the possibility of the re-establishment of the reproductive axis in male-to-female sexual reversal. This study investigated ovary survival and follicle development after mouse ovaries were transplanted into immune-intact castrated male mice. Ten-day-old mouse ovaries were transplanted into the back muscle of adult outbred castrated male mice treated with immunosuppressants. Twenty-two days later, the ovary structure and the number of follicles present was examined by hematoxylin and eosin staining. The oocytes were harvested, and then used for in vitro maturation (IVM) and IVF. The results showed that primordial and antral follicles were mainly found in the grafts, and there were obvious differences compared with 32-day-old fresh ovaries (PP