Preparation of Thermosensitive Hydrogels by means of Tandem Physical and Chemical Crosslinking

Hong-Liang Wei,Kai Yao,Zhe Yang,Hui-Juan Chu,Jing Zhu,Cun-Cai Ma,Zi-Xuan Zhao 한국고분자학회 2011 Macromolecular Research Vol.19 No.3

The tandem physical and chemical crosslinking was used to prepare injectable hydrogels. First, the terpolymers with diene groups were synthesized by the free radical copolymerization of N-isopropylacrylamide (NIPA), N,N-dimethylacrylamide (DMA) and furfuryl methacrylate (FM). Second, dienophile-functionalized terpolymers were obtained from the terpolymers of NIPA, DMA, and 2-hydroxyethyl methacrylate (HEMA) and Nmaleoyl alanine (AMI) by a coupling reaction under N,N'-dicyclohexylcarbodiimide (DCC). When the screened diene-functionalized terpolymer and dienophile-functionalized terpolymer were dissolved separately in water and mixed, physically cross-linked hydrogels formed rapidly within 10 s at 37 ℃. Subsequently, the physically crosslinked hydrogels could change gradually into chemically cross-linked hydrogels by a Diels-Alder reaction and the mechanical strength of the hydrogels could be improved. The swelling behavior study suggests that the hydrogels possess thermosensitivity and good reproducibility at different temperatures. The strategy described, i.e. incorporating the advantages of physically crosslinked hydrogels and chemically crosslinked hydrogels, has potential applications in the preparation of injectable hydrogels.

Continuous Cooling Transformation Behavior and Impact Toughness in Heat-Affected Zone of Nb-Containing Fire-Resistant Steel

Hong Hong Wang,Zhan Peng Qin,Xiang Liang Wan,Ran Wei,Kai Ming Wu,Devesh Misra 대한금속·재료학회 2017 METALS AND MATERIALS International Vol.23 No.5

Simulated heat-affected zone continuous cooling transformation diagram was developed for advanced fireresistantsteel. Over a wide range of cooling rates, corresponding to t8/5 from 6 s to 150 s, granular bainite was thedominant transformation constituent, while the morphology of less dominant martensite-austenite (M-A) constituentchanged from film-like to block-type constituent; but the hardness remained similar to the average value of 190-205 HV (0.2). The start and finish transformation temperature was high at 700 °C and 500 °C, and is different fromthe conventional high strength low alloy steels. It is believed that the high-content (0.09 wt%) of Nb may promotebainite transformation at relatively high temperatures. Martenistic matrix was not observed at high cooling rateand the film-like M-A constituent and blocky M-A constituent with thin film of retained austenite and lath martensitewere observed on slow cooling. Excellent impact toughness was obtained in the heat-affected zone with15-75 kJ/cm welding heat input.

Effects of drying methods on contents of bioactive compounds and antioxidant activities of Angelica dahurica

Wei-Hong Liang,Tung-Wu Chang,Yuh-Chyang Charng 한국식품과학회 2018 Food Science and Biotechnology Vol.27 No.4

Baizhi (Angelica dahurica) has been widely used as a traditional Chinese herbal medicine, functional food and cosmetic product ingredient, mostly because of the high furanocoumarin compounds in roots. Because the fresh root is perishable, drying techniques are needed to maintain a higher-quality product. Freeze-drying is the best method but energy-consuming and costly. The aim of this study was to analyze the quality (antioxidant and furanocoumarin content) of Baizhi roots after freeze-drying (the control) and in-the-shade, 40 and 70 C drying. Antioxidant activity was revealed by 2,2-diphenyl-1- picrylhydrazyl and Fe2? chelating assay, and the content of six furanocoumarin compounds, including xanthotoxin, bergapten, oxypeucedanin, imperatorin, phellopterin and isoimperatorin, was analyzed by liquid chromatography. Antioxidant activity was greater in roots with in-the-shade, 40 and 70 C drying than freeze-drying. The furanocoumarin content pattern was similar with 70 C drying and freeze-drying. A. dahurica roots dried at 70 C may be an alternative method for maintaining high quality.

Outcomes of Secondary Laminoplasty for Patients with Unsatisfactory Results after Anterior Multilevel Cervical Surgery

Liu, Hong-Wei,Chen, Liang,Xu, Nan-Wei,Yang, Hui-Lin,Gu, Yong The Korean Neurosurgical Society 2015 Journal of Korean neurosurgical society Vol.57 No.1

Objective : To investigate the causes for failed anterior cervical surgery and the outcomes of secondary laminoplasty. Methods : Seventeen patients failed anterior multilevel cervical surgery and the following conservative treatments between Feb 2003 and May 2011 underwent secondary laminoplasty. Outcomes were evaluated by the Japanese Orthopaedic Association (JOA) Scale and visual analogue scale (VAS) before the secondary surgery, at 1 week, 2 months, 6 months, and the final visit. Cervical alignment, causes for revision and complications were also assessed. Results : With a mean follow-up of $29.7{\pm}12.1$ months, JOA score, recovery rate and excellent to good rate improved significantly at 2 months (p< 0.05) and maintained thereafter (p>0.05). Mean VAS score decreased postoperatively (p<0.05). Lordotic angle maintained during the entire follow up (p>0.05). The causes for secondary surgery were inappropriate approach in 3 patients, insufficient decompression in 4 patients, adjacent degeneration in 2 patients, and disease progression in 8 patients. Complications included one case of C5 palsy, axial pain and cerebrospinal fluid leakage, respectively. Conclusion : Laminoplasty has satisfactory results in failed multilevel anterior surgery, with a low incidence of complications.

Study on the Hydrothermal Synthesis and Optical Properties of YVO4:Dy3+ Phosphor Powders

Hong-Tao Liu,Yan Liang,Xiao-Yong Gao,Sa Zhang,Xian-Wei Zhao,Xian-Mei Chen 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.8

YVO4:Dy3+ phosphor powders were synthesized by using the hydrothermal method under differentpH conditions. The crystallization, surface morphology, lattice vibration, optical properties,luminescent mechanism and influencing factors of the obtained YVO4:Dy3+ phosphor powders werecarefully studied and analyzed in detail. All of the YVO4:Dy3+ phosphor powders had tetragonalstructures, and the pH value had a significant impact on the surface morphology, structure andoptical properties of the synthesized samples. Strong acidic and alkali environments were favorablefor the crystallization of YVO4:Dy3+phosphor powders, and the YVO4:Dy3+ phosphor powderssynthesized under strong alkali environments had the best luminescent properties.

A preparation and performance study of glass-ceramic glazes derived from blast furnace slag and fly ash

Hong-xia Lu,Man He,Yuan-yuan Liu,Jing-fei Guo,Li-wei Zhang,Deliang Chen,Hai-long Wang,Hong-liang Xu,Rui Zhang 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.5

Glass-ceramic glazes have been prepared successfully via crystallization from blast-furnace slag (BFS), fly ash (FA) fluxed with potash feldspar and borax. The crystalline behavior of glass-ceramic glazes was investigated using differential thermal analysis and thermogravimetric analysis (DTA/TG), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results revealed that the major crystalline phases are anorthite (CaAl2Si2O8) and akermanite (Ca2MgSi2O7) and crystalline phases disperse well in glassy phases with a uniform size of 1 μm. Glass-ceramic glazes possess low density, low water absorption,perfect stain resistance, acid resistance and alkali resistance. The thermal expansion coefficient of glass-ceramic glazes is steady up to 800 oC with an average value of 7.2 × 10−6 /K. Final results suggest that BFS and FA have potential to be vitrified into economically and environmentally low-cost glass-ceramic glaze materials.

Radiofrequency Ablation Combined with Transcatheter Arterial Chemoembolization Therapy Versus Surgical Resection for Hepatocellular Carcinoma within the Milan Criteria: A Meta-Analysis

Wei-dong Wang,Li-hua Zhang,Jia-Yan Ni,Xiong-ying Jiang,Dong Chen,Yao-ting Chen,Hong-liang Sun,Jiang-hong Luo,Lin-feng Xu 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.4

Objective: To meta-analytically compare combined transarterial chemoembolization (TACE) plus radiofrequency ablation (RFA) and surgical resection (SR) for the treatment of hepatocellular carcinoma (HCC) within the Milan criteria. Materials and Methods: PubMed, Medline, Embase, and Cochrane Library were searched for studies comparing these two therapies that were published between January 2006 and August 2017. Overall survival rate (OS), recurrence-free survival rate (RFS), major complications and the average length of hospital stay were compared between these two therapies. Metaanalytic pooled odds ratio (OR) was calculated using TACE plus RFA as the base category. Results: Seven case-control studies and one randomized trial were identified. Meta-analytic results revealed that, compared with SR, TACE plus RFA had significantly higher 1-year OS (OR for survival = 0.50, p = 0.009) and lower major complications (OR = 1.88, p = 0.02) after therapy. Three studies reported on the length of hospital stay. The average length ± standard deviation reported in individual studies for SR and TACE plus RFA groups was 19.8 ± 8.4 days and 7.4 ± 2.2 days, respectively; 18.7 ± 4.9 days and 11.5 ± 6.9 days, respectively; and 16.6 ± 6.7 days and 8.5 ± 4.1 days, respectively (p < 0.0001 for all studies). Three or 5-year OS and 1-, 3-, or 5-year RFS did not significantly differ between the two therapies. Conclusion: Combined TACE plus RFA may be an alternative to SR for the treatment of patients with HCC within Milan the criteria. Non-randomized design in most of the original studies was a limitation.

Synthesis, Structures and Properties of Three Metal-organic Frameworks Based on 3-(4-((1H-imidazol-1-yl)methyl)phenyl)acrylic Acid

Liang, Peng,Ren, Tian-Tian,Tian, Wei-Man,Xu, Wen-Jia,Pan, Gang-Hong,Yin, Xian-Hong Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.1

Three new transition metal complexes based on Ozagrel $[Cu(Ozagrel)]_n$ (1), $[Zn(Ozagrel)(Cl)]_n$ (2), ${[Mn_2-(Ozagrel)(1,4-ndc)_2]{\cdot}(H_2O)}_n$ (3), (Ozagrel = 3-(4-((1H-imidazol-1-yl)methyl)phenyl)acrylic acid; 1,4-ndc = 1,4-Naphthalenedicarboxylic acid) have been hydrothermally synthesized and characterized by elemental analyse, IR, TG, PXRD, electrochemical analysis and single crystal X-ray diffraction. X-ray structure analysis reveals that 1 and 3 are 3D coordination polymers, while complex 2 is a two-dimensional network polymer, the 2D layers are further packed into 3D supramolecular architectures that are connected through hydrogen bonds. The electrochemistry of 1-3 was studied by cyclic voltammetry in methanol and water using a glassy carbon working electrode. Also, thermal decomposition process and powder X-ray diffraction of complexes were investigated.

A Discovery of Low Hydraulic Resistance Channel Along Meridians

Wei-Bo Zhang,Yu-Ying Tian,Hong Li,Jia-He Tian,Ming-Fu Luo,Fa-Liang Xu,Guang-Jun Wang,Tao Huang,Yi-Hui Xu,Rui-Hong Wang 사단법인약침학회 2008 Journal of Acupuncture & Meridian Studies Vol.1 No.1

A hydro-mechanic model was put forward to study the fundamental nature of acupuncture meridians. The basic state of low hydraulic resistance was tested on humans and mini pigs using three methods. The first, a modified Guyton’s method, proved that there was lower hydraulic resistance on meridians compared with nonmeridians. The second scanning method involved a single pressure transducer that can find the lowest resistance point in tissue, and the third method used two transducers and provided a more stable measurement. Using the latter method, low hydraulic resistance points were found very close to low impedance points along meridians. The transmission of artificial interstitial fluid pressure waves was measured to examine their connection to the low resistance points, with the result that a good connection between the points was confirmed. This means the points form channels along the meridians that we refer to as low hydraulic resistance channels. The channel was imaged through isotopic tracing and a migration of isotope 99mTe could be found along the channel. The layer of the channel was detected by injecting Alcian blue and the track was found beneath the skin. All of the above experiments suggest the existence of a new type of channel in living tissues that has not yet been described in modern science, but coincides quite well with the Qi channel theory of traditional Chinese medicine. A hydro-mechanic model was put forward to study the fundamental nature of acupuncture meridians. The basic state of low hydraulic resistance was tested on humans and mini pigs using three methods. The first, a modified Guyton’s method, proved that there was lower hydraulic resistance on meridians compared with nonmeridians. The second scanning method involved a single pressure transducer that can find the lowest resistance point in tissue, and the third method used two transducers and provided a more stable measurement. Using the latter method, low hydraulic resistance points were found very close to low impedance points along meridians. The transmission of artificial interstitial fluid pressure waves was measured to examine their connection to the low resistance points, with the result that a good connection between the points was confirmed. This means the points form channels along the meridians that we refer to as low hydraulic resistance channels. The channel was imaged through isotopic tracing and a migration of isotope 99mTe could be found along the channel. The layer of the channel was detected by injecting Alcian blue and the track was found beneath the skin. All of the above experiments suggest the existence of a new type of channel in living tissues that has not yet been described in modern science, but coincides quite well with the Qi channel theory of traditional Chinese medicine.

Metastasis associated genomic aberrations in stage II rectal cancer

Hong Zhao,Zhi-Zhou Shi,Rui Jiang,Dong-Bing Zhao,Hai-Tao Zhou,Jian-Wei Liang,Xin-Yu Bi,Jian-Jun Zhao,Zhi-Yu Li,Jian-Guo Zhou,Zhen Huang,Ye-Fan Zhang,Jian Wang,Xin Xu,Yan Cai,Ming-Rong Wang,Yu Zhang 한국유전학회 2016 Genes & Genomics Vol.38 No.11

Genomic aberrations of rectal carcinoma, especially DNA copy number changes associated with metastasis were largely unclear. We aim to identify the metastasis associated biomarkers in stage II rectal cancer. Formalin-fixed, paraffin-embedded primary tumor tissues of stage II rectal carcinoma were analyzed by array-based comparative genomic hybridization, and genomic aberrations were identified by Genomic Workbench and SAM software. Copy number changes and mRNA expressions were validated by Real-time PCR in an independent rectal cancer samples. The results showed that the most frequent gains in stage II rectal cancer were at 1q21.2-q23.1, 3p21.31, 11q12.2-q23.3, 12q24.11-q24.31, 12q13.11-q14.1 and losses in 18q11.2-q23, 17q21.33-q22, 13q31.1-q31.3, 21q21.1-q21.3, 8p23.3-p23.1 and 4q22.1-q23. Twenty-two amplifications and five homozygous deletions were also identified. We further found that S100A1 (1q21.3-q23.1), MCM7 (7q22.1) and JUND (19p13.11) were amplified and overexpressed in stage II rectal cancer. Interestingly, the genomic aberrations affected 14 signaling pathways including VEGF signaling pathway and fatty acid metabolism. Most importantly, loss of 13q31.1-q34 and gain of 1q44 were associated with distant metastasis. Our results indicated that these metastasis associated genomic changes may be useful to reveal the pathogenesis of rectal cancer metastasis and identify candidate biomarkers.