지연유합과 불유합에서 저신호 강도 초음파의 유용성

윤여헌,김종오,고영도,유재두,정준모,오종건,방한천,최창호,신명철 대한골절학회 2003 대한골절학회지 Vol.16 No.1

목 적 : 저 신호 강도 초음파를 이용한 지연유합과 불유합의 치료에 대한 유용성을 알아보고자 하였다. 대상 및 방법 : 2001년 7월부터 2002년 5월까지 본원에 내원한 지연유합 7례와 불유합 8례를 대상으로 5개월간 저 신호 강도 초음파로 치료하여 5개월후 골유합 여부를 알아 보았다. 결 과 : 총 15례 중 대퇴골 간부 2례, 경골 간부 1례, 상완골 간부 1례, 요골 1례의 지연유합에서 골유합을 얻었고 대퇴골 간부 불유합 3례에서 유합을 얻었다. 지연주합은 71%의 유합율을, 불유합은 37.5%의 유합율을 보였다. 결 론 : 저 신호 강도 초음파는 골유합을 촉진 시킬 수 있으며 지연유합에서 시도해 볼 만 하나 불유합 치료를 위해서는 보다 많은 연구가 필요 하다. Purpose : To evaluation of usefulness of low-intensity ultrasound for nonunion and delayed union. Materials and Methods : For 5 months, we treated 7 delayed union and 8 nonunion using low-intensity ultrasound. After 5 months, in checked X-ray AP and Lateral view, when cortical bridge formation was done, we through union. Results : In 7 delayed union, 5 cases-2 femur, tibia, humerus, radius were healed. In 8 nonunion, 3 femur nonunion were healed. Union rate was 71% in delayed union 37.5% in nonunion. Conclusion : we thought that the low-intensity ultrasound has capacity of induction of union and was considered as the method of treatment for delayed union.

Optical Coherence Tomographic Elastography Reveals Mesoscale Shear Strain Inhomogeneities in the Annulus Fibrosus

Han, Sang K.,Chen, Chao-Wei,Labus, Kevin M.,Puttlitz, Christian M.,Chen, Yu,Hsieh, Adam H. Lippincott Williams & Wilkins 2016 Spine Vol.41 No.13

<P>Study Design. Basic science study using in vitro tissue testing and imaging to characterize local strains in annulus fibrosus (AF) tissue. Objective. To characterize mesoscale strain inhomogeneities between lamellar and inter-/translamellar (ITL) matrix compartments during tissue shear loading. Summary of Background Data. The intervertebral disc is characterized by significant heterogeneities in tissue structure and plays a critical role in load distribution and force transmission in the spine. In particular, the AF possesses a lamellar architecture interdigitated by a complex network of extracellular matrix components that form a distinct ITL compartment. Currently, there is not a firm understanding of how the lamellar and ITL matrix coordinately support tissue loading. Methods. AF tissue samples were prepared from frozen porcine lumbar spines and mounted onto custom fixtures of a materials testing system that incorporates optical coherence tomography (OCT) imaging to perform tissue elastography. Tissues were subjected to 20 and 40% nominal shear strain, and OCT images were captured and segmented to identify regions of interest corresponding to lamellar and ITL compartments. Images were analyzed using an optical flow algorithm to quantify local shear strains within each compartment. Results. Using histology and OCT, we first verified our ability to visualize and discriminate the ITL matrix from the lamellar matrix in porcine AF tissues. Local AF strains in the ITL compartment (22.0 +/- 13.8, 31.1 +/- 16.9 at 20% and 40% applied shear, respectively) were significantly higher than corresponding strains in the surrounding lamellar compartment (12.1 +/- 5.6, 15.3 +/- 5.2) for all tissue samples (P<0.05). Conclusion. Results from this study demonstrate that the lamellar and ITL compartments of the AF distribute strain unevenly during tissue loading. Specifically, shear strain is significantly higher in the ITL matrix, suggesting that these regions may be more susceptible to tissue damage and more mechanobiologically active.</P>

Nucleophosmin modulates the alleviation of atopic dermatitis caused by the marine-derived compound dihydroaustrasulfone alcohol

Han-Chun Hung,Chien-Wei Feng,Yen-You Lin,Chun-Hong Chen,Kuan-Hao Tsui,Wu-Fu Chen,Chieh-Yu Pa,Jyh-Horng Sheu,Chun-Sung Sung,Zhi-Hong Wen 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

Atopic dermatitis (AD) is a chronic inflammatory skin disease, and its prevalence is increasing. AD usually elicits skin barrier dysfunction, dry skin and itching. As the mechanisms of AD remain unknown, there is an urgent need to find effective therapies. Because of the diversity and complexity of marine environments, the discovery of drugs from marine organisms as novel therapeutic agents for human diseases has seen renewed interest. Dihydroaustrasulfone alcohol (WA-25), the synthetic precursor of austrasulfone, which is a natural product isolated from a Formosan soft coral, has been shown to possess many therapeutic effects in our previous studies. However, the detailed mechanisms and therapeutic effects of WA-25 on AD are incompletely understood. We performed in vitro and in vivo studies to examine the effects of WA-25 on AD. We showed that WA-25 blocks inflammation and oxidative stress. Simultaneously, we also found that WA-25 reduces the AD scores and AD-induced transepidermal water loss (TEWL), scratching behavior, and alloknesis. WA-25 is more effective in cases of AD than are the drugs that are currently used clinically. Importantly, we also found that when nucleophosmin (NPM) was inhibited or when its expression was reduced, the anti-inflammatory and anti-AD effects of WA-25 were blocked. These data suggest that NPM plays dual roles in inflammation and AD. Overall, these results suggest that WA-25 is a potential anti-inflammatory and AD therapeutic agent that is modulated by NPM.

Expand Genetic Carrier Screening and Counseling

( Han-ying Chen ) 대한산부인과학회 2023 대한산부인과학회 학술대회 Vol.109 No.-

Simulation and Design Considerations on Transverse Connection of Prestressed Concrete T-girder Bridge

Chen Chen,Caiqian Yang,Yong Pan,Honglei Zhang,Hans De Backer 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.4

In this paper, the structural performance of the prestressed concrete T-girder bridge with a newly proposed diaphragm transverse connections (DTCs) have been investigated. The DTCs are composed of diagonal braces and horizontal brace, and the braces are structural steel with square cross section. A series of simulations have been carried out to study the eff ectiveness of the proposed DTCs on enhancing the transverse connection of the prestressed concrete T-girder bridge. Load Model 1 in accordance with Eurocode 1 is considered in the simulations, which consists of tandem system and uniformly distributed loads (UDL system). The Von Mises stress of the DTCs has been checked and corresponding steel grade has been given. The force on the surface between the T-girder bridge and the proposed DTCs has been studied and detailed connection design has been given for both new bridge construction and existing bridge retrofi tting. The simulation results show that the maximum defl ection arises when the deck is fully loaded with the UDL system and with lane 1 centrally located on exterior girder, and the tandem systems are applied at midspan simultaneously. It is revealed that with the proposed DTCs installed at midspan, the maximum defl ection of the prestressed concrete T-girder bridge reduces 12.8% in the most unfavorable load case. In all the discussed load cases, the Von Mises stress of the proposed DTCs is within the reasonable range and can be borne by normal steel material. Additionally, connection methods have been given for the DTCs’ application to new bridge and existing bridge. For the use of chemical anchor in existing bridge, the concrete and prestress tendons should be checked in case of any additional damage during the installing of the DTCs.

Strong and biocompatible poly(lactic acid) membrane enhanced by Ti₃C₂T_z (MXene) nanosheets for Guided bone regeneration

Chen, Ke,Chen, Youhu,Deng, Qihuang,Jeong, Seol-Ha,Jang, Tae-Sik,Du, Shiyu,Kim, Hyoun-Ee,Huang, Qing,Han, Cheol-Min Elsevier 2018 Materials letters Vol.229 No.-

<P><B>Abstract</B></P> <P>Herein, strong and biocompatible Ti<SUB>3</SUB>C<SUB>2</SUB>T<SUB>z</SUB>-enhanced poly(lactic acid) (PLA) nanocomposite membranes were prepared. The interface of the Ti<SUB>3</SUB>C<SUB>2</SUB>T<SUB>z</SUB> nanosheets with the hydrophobic PLA matrix was mediated using n-octyltriethoxysilane (OTES). The optimized ultimate tensile strength of the OTES-Ti<SUB>3</SUB>C<SUB>2</SUB>T<SUB>z</SUB>/PLA nanocomposite membrane was 72 MPa (33% higher than that of a pure PLA membrane). The addition of Ti<SUB>3</SUB>C<SUB>2</SUB>T<SUB>z</SUB> enhanced the biological properties of the membrane, including the <I>in vitro</I> adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 mouse preosteoblasts.</P> <P><B>Highlights</B></P> <P> <UL> <LI> First effort to introduce MXene into polymer matrix for tissue engineering. </LI> <LI> A robust strategy developed to prepare Ti<SUB>3</SUB>C<SUB>2</SUB>T<SUB>z</SUB>-enhanced PLA nanocomposite. </LI> <LI> Successful interfacial mediation between hydrophilic Ti<SUB>3</SUB>C<SUB>2</SUB>T<SUB>z</SUB> nanosheets and hydrophobic PLA. </LI> <LI> Intriguing future of this strong and biocompatible nanocomposite for GBR membrane. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Direct Synthesis of H2O2 over Ti-Containing Molecular Sieves Supported Gold Catalysts: A Comparative Study for In-situ-H2O2-ODS of Fuel

Han Zhang,Guangliang Liu,Haiyan Song,Chunxia Chen,Fuqin Han,Ping Chen,Zhixi Zhao,Shaozheng Hu 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.10

Direct synthesis of H2O2 and in situ oxidative desulfurization of model fuel over Au/Ti-HMS and Au/TS-1 catalysts has been comparatively investigated in water or methanol. Maximum amount (82%) of active Au0 species for H2O2 synthesis was obtained. Au/Ti-HMS and Au/TS-1 exhibited the contrary performances in H2O2 synthesis as CH3OH/H2O ratio of solvent changed. H2O2 decomposition and hydrogenation in water was inhibited by the introduction of methanol. Effect of O2/H2 ratio on H2O2 concentration, H2 conversion and H2O2 selectivity revealed a relationship between H2O2 generation and H2 consumption. The highest dibenzothiophene removal rate (83.2%) was obtained over Au/Ti-HMS in methanol at 1.5 of O2/H2 ratio and 60 oC. But removal of thiophene over Au/TS-1 should be performed in water without heating to obtain a high removal rate (61.3%). Meanwhile, H2 conversion and oxidative desulfurization selectivity of H2 were presented.

HPF1 regulates tendon stem/progenitor cell senescence and tendon repair via PARP1-mediated poly-ADP ribosylation of HuR

Han Weifeng,GU Dongqiang,Chen Hongguang,Tao Xu,Chen Lei 한국유전학회 2024 Genes & Genomics Vol.46 No.1

Background Tendon stem/progenitor cells (TSPCs) play a vital role in tendon repair, regeneration and homeostasis. However, the specific mechanism of TSPCs aging is still unclear. Objective This study aims to explore the role and molecular mechanism of HPF1 in the aging of TSPCs. Methods Young and aged TSPCs (Y-TSPCs and A-TSPCs) were acquired from 3 to 4 and 24–26-month-old Sprague–Dawley male rats, TSPCs (Y-TSPCs and A-TSPCs) were subjected to senescence-associated β-galactosidase (SA-β-Gal))staining and telomerase activity detection, p16, p21, Scx, Tnmd, Col1, Col3HPF1 and PAPR1 expression levels were detected by Western blot or Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR), Reciprocal co-immunoprecipitation (co-IP) was used to explore the interaction between HPF1 and PARP1. Ribonucleoprotein immunoprecipitation (RNP-IP) was used to analyze the binding of HuR to the senescence marker gene mRNAs, IP was used to perform HPF1 to the PARylation of HuR, and the half-life of p16 and p21 were detected. Finally, we established an in vivo model, and the tendon tissue was used to perform hematoxylin and eosin (HE) and masson’s trichrome staining, as well as the immunohistochemical analysis of Col I and TNMD. Results Compared with Y-TSPCs, A-TSPCs had significantly enhanced cell senescence and significantly reduced tendon differentiation ability, and significantly increased the expression of HPF1 and PARP1. In addition, HPF1 and PARP1 interacted and coordinated the senescence and differentiation of TSPCs, HPF1 could also regulate the expression of p21 and p21, the interaction of p16 or p21 with HuR, and the poly-ADP ribosylation of PARP1 to HuR. HPF1 overexpression and siHuR co-transfection significantly reduced the half-life of p16 and p21, and HPF1 and PARP1 regulated the mRNA levels of p16 and p21 through HuR. Finally, in vivo experiments have shown that HPF1 or PARP1 overexpression could both inhibit the ability of tendon differentiation and promote cell senescence. Conclusions HPF1 promoted the senescence of TSPCs and inhibits the tendon differentiation of TSPCs through PARP1-mediated poly-ADP ribosylation of HuR. Similar content being viewed by others Background Tendon stem/progenitor cells (TSPCs) play a vital role in tendon repair, regeneration and homeostasis. However, the specific mechanism of TSPCs aging is still unclear. Objective This study aims to explore the role and molecular mechanism of HPF1 in the aging of TSPCs. Methods Young and aged TSPCs (Y-TSPCs and A-TSPCs) were acquired from 3 to 4 and 24–26-month-old Sprague–Dawley male rats, TSPCs (Y-TSPCs and A-TSPCs) were subjected to senescence-associated β-galactosidase (SA-β-Gal))staining and telomerase activity detection, p16, p21, Scx, Tnmd, Col1, Col3HPF1 and PAPR1 expression levels were detected by Western blot or Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR), Reciprocal co-immunoprecipitation (co-IP) was used to explore the interaction between HPF1 and PARP1. Ribonucleoprotein immunoprecipitation (RNP-IP) was used to analyze the binding of HuR to the senescence marker gene mRNAs, IP was used to perform HPF1 to the PARylation of HuR, and the half-life of p16 and p21 were detected. Finally, we established an in vivo model, and the tendon tissue was used to perform hematoxylin and eosin (HE) and masson’s trichrome staining, as well as the immunohistochemical analysis of Col I and TNMD. Results Compared with Y-TSPCs, A-TSPCs had significantly enhanced cell senescence and significantly reduced tendon differentiation ability, and significantly increased the expression of HPF1 and PARP1. In addition, HPF1 and PARP1 interacted and coordinated the senescence and differentiation of TSPCs, HPF1 could also regulate the expression of p21 and p21, the interaction of p16 or p21 with HuR, and the poly-ADP ribosylation of PARP1 to HuR. HPF1 overexpression and siHuR co-transfection significantly reduced the half-life of p16 and p21, and HPF1 and PARP1 regulated the mRNA levels of p16 and p21 through HuR. Finally, in vivo experiments have shown that HPF1 or PARP1 overexpression could both inhibit the ability of tendon differentiation and promote cell senescence. Conclusions HPF1 promoted the senescence of TSPCs and inhibits the tendon differentiation of TSPCs through PARP1-mediated poly-ADP ribosylation of HuR. Similar content being viewed by others

Removal of the Glycosylation of Prion Protein Provokes Apoptosis in SF126

Chen, Lan,Yang, Yang,Han, Jun,Zhang, Bao-Yun,Zhao, Lin,Nie, Kai,Wang, Xiao-Fan,Li, Feng,Gao, Chen,Dong, Xiao-Ping,Xu, Cai-Min Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.5

Although the function of cellular prion protein (PrP$^C$) and the pathogenesis of prion diseases have been widely described, the mechanisms are not fully clarified. In this study, increases of the portion of non-glycosylated prion protein deposited in the hamster brains infected with scrapie strain 263K were described. To elucidate the pathological role of glycosylation profile of PrP, wild type human PrP (HuPrP) and two genetic engineering generated non-glycosylated PrP mutants (N181Q/N197Q and T183A/T199A) were transiently expressed in human astrocytoma cell line SF126. The results revealed that expressions of non-glycosylated PrP induced significantly more apoptosis cells than that of wild type PrP. It illustrated that Bcl-2 proteins might be involved in the apoptosis pathway of non-glycosylated PrPs. Our data highlights that removal of glycosylation of prion protein provokes cells apoptosis.

Centrifuge Model Tests and Numerical Simulations of the Landslide Evolution Process

Han-Dong Liu,Jia-Xing Chen,Wen-Xi Han,Ye Wu,Dong-Dong Li 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.6

Centrifuge model tests and numerical simulations were performed to study the landslide evolution process and failure mechanism. A TLJ-500 geotechnical centrifuge was used for the experiments and landslide deformation and stress was monitored using high-precision differential displacement sensors and earth pressure micro-sensors. Discrete element numerical simulations were performed using PFC2D based on the experimental results. The findings show that the landslide evolution process can be divided into three stages: 1) compaction and consolidation; 2) uniform deformation; and 3) accelerated deformation and failure. The numerical simulation results verify the distinct stage characteristics of the landslide evolution process. According to the migration of microscopic soil mass particles within the landslide, stage 3) can be further divided into a deformation development stage and instability and failure stage. The simulation displacement monitoring curves and displacement map show distinct deformation characteristics and displacement indicators from stages 2) to 3) and from the deformation development stage to the instability and failure stage. The experimental and numerical results reveal the landslide failure mechanism: the upper part of the landslide thrusts and slides; the middle part squeezes; the lower part collapses; and shear plane penetration leads to landslide failure.