In situ growth of CdS spherical nanoparticles/Ti3C2 MXene nanosheet heterojunction with enhanced photocatalytic hydrogen evolution

Kai Chun-Mei,Kong Cui,Zhang Feng-Jun,Li Dong-Cai,Wang Ying-Rui,오원춘 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.3

Solar photocatalytic hydrogen production is considered as a potential solution to alleviate the current global energy situation. In this work, a novle CdS spherical nanoparticles/Ti3C2 MXene nanosheet (CM) heterostructure photocatalyst was prepared by in situ growth method, which has the characteristics of high efficiency and stability. The results showed that the CM sam- ple has regular morphology and size. When compared with pure CdS, its specific surface area increased and the hydrogen evolution performance also greatly improved. Among them, the hydrogen evolution of CM-0.06 is 1295 μmol·g−1·h−1 (λ > 420 nm), which is 7 times that of spherical CdS, and it also showed stronger stability. Tight interface contact can promote the transfer and migration of photo-generated carriers, and the effective separation of electron hole pairs can enhance the absorption of visible light. In addition, Ti3C2 MXene acts as an electron trap can further accelerate the separation of pho- togenerated electrons and holes. The synergistic effect between semiconductor CdS and Ti3C2 MXene nanosheets, which provides a new idea for the design of more stable and efficient CdS-based photocatalysts.

Kojic Acid Protects C57BL/6 Mice from Gamma-irradiation Induced Damage

Wang, Kai,Liu, Chao,Di, Chan-Juan,Ma, Cong,Han, Chun-Guang,Yuan, Mei-Ru,Li, Peng-Fei,Li, Lu,Liu, Yong-Xue Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

The radioprotective effects of a single administration of kojic acid (KA) against ionizing radiation were evaluated via assessment of 30-day survival and alterations of peripheral blood parameters of adult C57BL/6 male mice. The 30-day survival rate of mice pretreated with KA (75 or 300 mg/kg body weight, KA75 or KA300) subcutaneously 27 h prior to a lethal dose (8 Gy, 153.52 cGy/min) of gamma irradiation was higher than that of mice irradiated alone (40% or 60% vs 0%). It was observed that the white blood cell (WBC) count/the red blood cell (RBC) count, haemoglobin content, haematocrit and platelet count of mice with or without KA pretreatment as exposed to a sub-lethal dose (4 Gy, 148.14 cGy/min) of gamma irradiation decreased maximally at day 4/day 8 post-irradiation. Although the initial WBC values were low in KA300 or WR-2721 (amifostine) groups, they significantly recovered to normal at day 19, whereas in the control group they did not. The results from the cytotoxicity and cell viability assays demonstrated that KA could highly protect Chinese hamster ovary (CHO) cells against ionizing radiation with low toxicity. In summary, KA provides marked radioprotective effects both in vivo and in vitro.

Comparison of Serum Ketone Levels and Cardiometabolic Efficacy of Dapagliflozin versus Sitagliptin among Insulin-Treated Chinese Patients with Type 2 Diabetes Mellitus

Chi-Ho Lee,Mei-Zhen Wu,David Tak-Wai Lui,Darren Shing-Hei Chan,Carol Ho-Yi Fong,Sammy Wing-Ming Shiu,Ying Wong,Alan Chun-Hong Lee,Joanne King-Yan Lam,Yu-Cho Woo,Karen Siu-Ling Lam,Kelvin Kai-Hang Yiu 대한당뇨병학회 2022 Diabetes and Metabolism Journal Vol.46 No.6

Background: Insulin-treated patients with long duration of type 2 diabetes mellitus (T2DM) are at increased risk of ketoacidosis related to sodium-glucose co-transporter 2 inhibitor (SGLT2i). The extent of circulating ketone elevation in these patients remains unknown. We conducted this study to compare the serum ketone response between dapagliflozin, an SGLT2i, and sitagliptin, a dipeptidyl peptidase-4 inhibitor, among insulin-treated T2DM patients.Methods: This was a randomized, open-label, active comparator-controlled study involving 60 insulin-treated T2DM patients. Participants were randomized 1:1 for 24-week of dapagliflozin 10 mg daily or sitagliptin 100 mg daily. Serum β-hydroxybutyrate (BHB) levels were measured at baseline, 12 and 24 weeks after intervention. Comprehensive cardiometabolic assessments were performed with measurements of high-density lipoprotein cholesterol (HDL-C) cholesterol efflux capacity (CEC), vibration-controlled transient elastography and echocardiography.Results: Among these 60 insulin-treated participants (mean age 58.8 years, diabetes duration 18.2 years, glycosylated hemoglobin 8.87%), as compared with sitagliptin, serum BHB levels increased significantly after 24 weeks of dapagliflozin (P=0.045), with a median of 27% increase from baseline. Change in serum BHB levels correlated significantly with change in free fatty acid levels. Despite similar glucose lowering, dapagliflozin led to significant improvements in body weight (P=0.006), waist circumference (P=0.028), HDL-C (P=0.041), CEC (P=0.045), controlled attenuation parameter (P=0.007), and liver stiffness (P=0.022). Average E/e’, an echocardiographic index of left ventricular diastolic dysfunction, was also significantly lower at 24 weeks in participants treated with dapagliflozin (P=0.037).Conclusion: Among insulin-treated T2DM patients with long diabetes duration, compared to sitagliptin, dapagliflozin modestly increased ketone levels and was associated with cardiometabolic benefits.

Comparative global immune-related gene profiling of somatic cells, human pluripotent stem cells and their derivatives: implication for human lymphocyte proliferation

Chia-Eng Wu,Chen-Wei Yu,Kai-Wei Chang,Wen-Hsi Chou,Chen-Yu Lu,Elisa Ghelfi,Fang-Chun Wu,Pey-Shynan Jan,Mei-Chi Huang,Patrick Allard,Shau-Ping Lin,Hong-Nerng Ho,Hsin-Fu Chen 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

Human pluripotent stem cells (hPSCs), including embryonic stem cells (ESCs) and induced PSCs (iPSCs), represent potentially unlimited cell sources for clinical applications. Previous studies have suggested that hPSCs may benefit from immune privilege and limited immunogenicity, as reflected by the reduced expression of major histocompatibility complex class-related molecules. Here we investigated the global immune-related gene expression profiles of human ESCs, hiPSCs and somatic cells and identified candidate immune-related genes that may alter their immunogenicity. The expression levels of global immune-related genes were determined by comparing undifferentiated and differentiated stem cells and three types of human somatic cells: dermal papilla cells, ovarian granulosa cells and foreskin fibroblast cells. We identified the differentially expressed genes CD24, GATA3, PROM1, THBS2, LY96, IFIT3, CXCR4, IL1R1, FGFR3, IDO1 and KDR, which overlapped with selected immune-related gene lists. In further analyses, mammalian target of rapamycin complex (mTOR) signaling was investigated in the differentiated stem cells following treatment with rapamycin and lentiviral transduction with specific short-hairpin RNAs. We found that the inhibition of mTOR signal pathways significantly downregulated the immunogenicity of differentiated stem cells. We also tested the immune responses induced in differentiated stem cells by mixed lymphocyte reactions. We found that CD24- and GATA3-deficient differentiated stem cells including neural lineage cells had limited abilities to activate human lymphocytes. By analyzing the transcriptome signature of immune-related genes, we observed a tendency of the hPSCs to differentiate toward an immune cell phenotype. Taken together, these data identify candidate immune-related genes that might constitute valuable targets for clinical applications.

Research progress of defective MoS2 for photocatalytic hydrogen evolution

Liu Chao,Kong Cui,Zhang Feng-Jun,Kai Chun-Mei,Cai Wei-Qin,Sun Xian-Yang,오원춘 한국세라믹학회 2021 한국세라믹학회지 Vol.58 No.2

The potential application of MoS 2 as a potential H 2 precipitation photocatalyst has received widespread attention and is considered a promising alternative to precious metal cocatalysts due to its richness and low cost. However, the catalytic active center of MoS 2 is only along the edge of the MoS 2 layer. Both theoretical and experimental studies have shown that defect engineering can increase the active site of MoS 2 and has superior activity in catalytic reactions. Therefore, this review describes the nature, defect types, and preparation of defective MoS 2 . Due to the recombination of MoS 2 and semiconductor has specifi c interface characteristics, Schottky heterojunctions can provide accelerated charge separation and lower Schottky barriers for photocatalytic applications, they are eff ective photocatalysts. Therefore, the preparation of the defect MoS 2 -supported semiconductor photocatalyst and its application in the photocatalytic water splitting reaction are also introduced. This article’s profound understanding of defects can consolidate basic photocatalysis theory and provide new insights for the rational design of satisfactory defect engineering photocatalytic materials.

Preparation of 2D/2D g-C3N4/Ti3C2 MXene composites by calcination synthesis method for visible light photocatalytic degradation of tetracycline

Qiao Le-Le,Zhang Feng-Jun,Kai Chun-Mei,Liu Chao,Wang Ying-Rui,Oh Won-Chun 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.5

In this work, an ultrathin 2D/2D g-C3N4/Ti3C2 heterojunction was synthesized by direct calcination of a mixture of urea and multilayer Ti3C2 for photocatalytic degradation of tetracycline. Among them, urea is the precursor for the generation of g-C3N4 and generates gas to peel the multilayer Ti3C2 into fewer layers while reacting, solving the problem of low yield for the preparation of fewer layers of Ti3C2. The experimental results of tetracycline degradation under visible light showed that pure g-C3N4 (UCN) exhibited weak photoactivity; however, its photocatalytic performance was enhanced when Ti3C2 was coupled with g-C3N4. The best sample (5TC) could degrade 90.1% of tetracycline within 30 min. After four cycles of stability test, the photocatalytic performance did not change significantly, indicating that the prepared 2D/2D g-C3N4/Ti3C2 heterojunction possesses strong photocatalytic performance along with good stability.

Photocatalytic CO2 Reduction over g-C3N4 Based Materials

Wei-Qin Cai,Feng-Jun Zhang,Cui Kong,Chun-Mei Kai,Won-Chun Oh 한국재료학회 2020 한국재료학회지 Vol.30 No.11

Reducing CO2 into high value fuels and chemicals is considered a great challenge in the 21st century. Efficiently activating CO2 will lead to an important way to utilize it as a resource. This article reviews the latest progress of g-C3N4 based catalysts for CO2 reduction. The different synthetic methods of g-C3N4 are briefly discussed. Article mainly introduces methods of g-C3N4 shape control, element doping, and use of oxide compounds to modify g-C3N4. Modified g-C3N4 has more reactive sites, which can significantly reduce the probability of photogenerated electron hole recombination and improve the performance of photocatalytic CO2 reduction. Considering the literature, the hydrothermal method is widely used because of its simple equipment and process and easy control of reaction conditions. It is foreseeable that hydrothermal technology will continue to innovate and usher in a new period of development. Finally, the prospect of a future reduction of CO2 by g-C3N4-based catalysts is predicted.