High-Performance Self-Expanding NiTi Stents Manufactured by Laser Powder Bed Fusion

Xiang Li,Shijie Hao,Baopeng Du,Bo Feng,Haohang Li,Ping Qiu,Bingmin Huang,Lishan Cui,Ying Yang 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.5

Laser powder bed fusion (LPBF) is a promising technology for the manufacturing of customized medical implants, due tothe intrinsic potential in the fabrication of components with complex geometries. However, for the LPBF-produced vascularimplants, the dimensional accuracy, forming quality and surface finish are still unable to satisfy the medical requirements. This work provides a systematic study on dimensional accuracy control, relative density, surface polishing, shape memoryfunction, superelasticity property and deployment capability of LPBF-produced self-expanding NiTi stents, aiming at promotingtheir application in the biomedical field. The dimensional deviation of stent struts between designed prototype andas-melted products is reduced to 3% by applying laser beam compensation (LBC) strategy. Meanwhile, the study reveals thatthe LBC parameters have strong influence on the relative density of NiTi stents. 99.89% of relative density is achieved forLPBF-produced NiTi stent as the LBC value is optimized to 120 μm. The incompletely melted powders, balling and rippingstructures on the surface of NiTi stents are observed to exhibit different removal processes during electrochemical polishing. The surface roughness (Ra) of NiTi stent is decreased from 7.17 μm for as-melted stent to 0.34 μm for as-polished one. Basedon high relative density and surface quality, the stents exhibit excellent shape memory function and superelasticity propertyin the process of cyclic deformation. Finally, the deployment capability of the stents is assessed. The results confirm thatLPBF-produced NiTi stents can be successfully crimped and released during the deployment process.

Study on the structure of reduced graphene oxide prepared by different reduction methods

Xiang Xu,Zhu Ying,Gao Changqin,Du Han,Guo Chunwen 한국탄소학회 2022 Carbon Letters Vol.32 No.2

The reduced graphene oxide (rGO) has attracted more and more attention in recent years. How to choose a suitable reduction method to prepare rGO is a critical problem in the preparation of graphene composites. In this work, the differences of rGO reduced by thermal, microwave, Ultraviolet (UV) and reducing agent were studied. The reduction degree and functional groups of rGO were compared by SEM, XPS, Raman, FTIR and TGA. Thermal can remove most of the oxygen-containing groups of graphene oxide (GO) and the thermal reduction is the most effective reduction method. UV light can directly act on the unstable oxygen-containing groups, and its reduction efficiency is second only to thermal reduction. The efficiency of chemical reduction is not as good as that of UV reduction, because the reducing agent only act on the surface of GO. Microwave reduction is a mild thermal reduction with the lowest efficiency, but the residual oxygen-containing groups increase the hydrophilicity of rGO. To sum up, this work studies that rGO prepared by different reduction methods has different characteristics, which provides a reference for selecting appropriate reduction methods to prepare graphene composites with better properties.

Analysis of Cancer Incidence in Zhejiang Cancer Registry in China during 2000 to 2009

Du, Ling-Bin,Li, Hui-Zhang,Wang, Xiang-Hui,Zhu, Chen,Liu, Qing-Min,Li, Qi-Long,Li, Xue-Qin,Shen, Yong-Zhou,Zhang, Xin-Pei,Ying, Jiang-Wei,Yu, Chuan-Ding,Mao, Wei-Min Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

Objective: The Zhejiang Provincial Cancer Prevention and Control Office collected cancer registration data during 2000 to 2009 from 6 cancer registries in Zhejiang province of China in order to analyze the cancer incidence. Methods: Descriptive analysis included cancer incidence stratified by sex, age and cancer site group. The proportions and cumulative rates of 10 common cancers in different groups were also calculated. Chinese population census in 1982 and Segi's population were used for calculating age-standardized incidence rates. The log-linear model was used for fitting to calculate the incidence trends. Results: The 6 cancer registries in Zhejiang province in China covered a total of 60,087,888 person-years during 2000 to 2009 (males 30,445,904, females 29,641,984). The total number of new cancer cases were 163,104 (males 92,982, females 70,122). The morphology verified cases accounted for 69.7%, and the new cases verified only by information from death certification accounted for 1.23%. The crude incidence rate in Zhejiang cancer registration areas was $271.5/10^5$ during 2000 to 2009 (male $305.41/10^5$, female $236.58/10^5$), age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population (ASIRW) were $147.1/10^5$ and $188.2/10^5$, the cumulative incidence rate (aged from 0 to 74) being 21.7%. The crude incidence rate was $209.6/10^5$ in 2000, and it increased to $320.20/10^5$ in 2009 (52.8%), with an annual percent change (APC) of 4.51% (95% confidence interval, 3.25%-5.79%). Age-specific incidence rate of 80-84 age group was achieved at the highest point of the incidence curve. Overall with different age groups, the cancer incidences differed, the incidence of liver cancer being highest in 15-44 age group in males; the incidence of breast cancer was the highest in 15-64 age group in females; the incidences of lung cancer were the highest in both males and females over the age of 65 years. Conclusions: Lung cancer, digestive system malignancies and breast cancer are the most common cancers in Zhejiang province in China requiring an especial focus. The incidences of thyroid cancer, prostate cancer, cervical cancer and lymphoma have increased rapidly. Prevention and control measures should be implemented for these cancers.

Appropriate Soil Heat Treatment Promotes Growth and Disease Suppression of Panax notoginseng by Interfering with the Bacterial Community

( Ying-bin Li ),( Zhi-ping Zhang ),( Ye Yuan ),( Hui-chuan Huang ),( Xin-yue Mei ),( Fen Du ),( Min Yang ),( Yi-xiang Liu ),( Shu-sheng Zhu ) 한국미생물 · 생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.3

In our greenhouse experiment, soil heat treatment groups (50, 80, and 121°C) significantly promoted growth and disease suppression of Panax notoginseng in consecutively cultivated soil (CCS) samples (p < 0.01), and 80°C worked better than 50°C and 121°C (p < 0.01). Furthermore, we found that heat treatment at 80°C changes the microbial diversity in CCS, and the inhibition ratios of culturable microorganisms, such as fungi and actinomycetes, were nearly 100%. However, the heat-tolerant bacterial community was preserved. The 16S rRNA gene and internal transcribed spacer (ITS) sequencing analyses indicated that the soil heat treatment had a greater effect on the Chao1 index and Shannon’s diversity index of bacteria than fungi, and the relative abundances of Firmicutes and Proteobacteria were significantly higher than without heating (80 and 121°C, p < 0.05). Soil probiotic bacteria, such as Bacillus (67%), Sporosarcina (9%), Paenibacillus (6%), Paenisporosarcina (6%), and Cohnella (4%), remained in the soil after the 80°C and 121°C heat treatments. Although steam increased the relative abundances of most of the heat-tolerant microbes before sowing, richness and diversity gradually recovered to the level of CCS, regardless of fungi or bacteria, after replanting. Thus, we added heat-tolerant microbes (such as Bacillus) after steaming, which reduced the relative abundance of pathogens, recruited antagonistic bacteria, and provided a long-term protective effect compared to the steaming and Bacillus alone (p < 0.05). Taken together, the current study provides novel insight into sustainable agriculture in a consecutively cultivated system.

Purification and Biochemical Characterization of a Novel Fibrinolytic Enzyme from Streptomyces sp. P3

( Guang Yan Cheng ),( Li Ying He ),( Zhi Bin Sun ),( Zhong Li Cui ),( Ying Xiang Du ),( Yi Kong ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.9

A novel proteolytic enzyme with fibrinolytic activity, FSP3, was purified from the recently isolated Streptomyces sp. P3, which is a novel bacterial strain isolated from soil. FSP3 was purified to electrophoretic homogeneity by ammonium sulfate precipitation, anion exchange, and gel filtration. FSP3 is considered to be a single peptide chain with a molecular mass of 44 kDa. The maximum activity of the enzyme was observed at 50°C and pH 6.5, and the enzyme was stable between pH 6 and 8 and below 40°C. In a fibrin plate assay, FSP3 showed more potent fibrinolytic activity than urokinase, which is a clinical thrombolytic agent acting as a plasminogen activitor. The activity was strongly inhibited by the serine protease inhibitor PMSF, indicating that it is a serine protease. Additionally, metal ions showed different effects on the activity. It was significantly suppressed by Mg2+ and Ca2+ and completely inhibited by Cu2+, but slightly enhanced by Fe2+. According to LC-MS/MS results, its partial amino acid sequences are significantly dissimilar from those of previously reported fibrinolytic enzymes. The sequence of a DNA fragment encoding FSP3 contained an open reading frame of 1287 base pairs encoding 428 amino acids. FSP3 is a bifunctional enzyme in nature. It hydrolyzes the fibrin directly and activates plasminogen, which may reduce the occurrence of side effects. These results suggest that FSP3 is a novel serine protease with potential applications in thrombolytic therapy.

Studies on the Ginseng Polypeptide - Decreasing Blood Sugar and Hapatic Glycogen

(Jin Zhang),(Hong Ying Zhang),(Wen Yun Du),(Da Wei Wang),(Ben Xiang Wang),(Ming Yang),(Yu Lian Jin),(Zhi Yong Cui),(Yan Wang) 고려인삼학회 1990 Proceedings of International Symposium on Korean G Vol.- No.-

EGFR Mutation Testing Practices within the Asia Pacific Region: Results of a Multicenter Diagnostic Survey

Yatabe, Yasushi,Kerr, Keith M.,Utomo, Ahmad,Rajadurai, Pathmanathan,Tran, Van Khanh,Du, Xiang,Chou, Teh-Ying,Enriquez, Ma. Luisa D.,Lee, Geon Kook,Iqbal, Jabed,Shuangshoti, Shanop,Chung, Jin-Haeng,Hag Elsevier 2015 JOURNAL OF THORACIC ONCOLOGY Vol.10 No.3

<P>The efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in EGFR mutation-positive non-small-cell lung cancer (NSCLC) patients necessitates accurate, timely testing. Although EGFR mutation testing has been adopted by many laboratories in Asia, data are lacking on the proportion of NSCLC patients tested in each country, and the most commonly used testing methods.</P>