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        • SCISCIESCOPUS

          Synthesis of TiB2/Fe-Cr-Al nanocomposite powder.

          Sachan, Ritesh,Park, Jong-Woo American Scientific Publishers 2008 Journal of nanoscience and nanotechnology Vol.8 No.10

          <P>In this study, a route for synthesizing TiB2/Fe-Cr-Al nanocomposite is proposed via high energy ball milling by using directly coarse powders of TiB2, Fe, Cr and Al. Various compositions of these powder mixtures are milled up to 48 hrs to investigate the effect of composition on the crystalline refinement. The crystalline size is analyzed by an X-ray diffractometer for powder samples containing 30 to 100 wt% TiB2 (the rest of the powder consists of Fe-20 wt%Cr-5 wt%Al composition). The crystalline size after 48 hrs of ball milling decreases with increasing TiB2, and then again increases after reaching a minimum value of 18 nm at 70% TiB2. By transmission electron microscopic analysis, it is confirmed that particles of TiB2 are significantly reduced and finely dispersed in the Fe-Cr-Al matrix. The particle size of TiB2 is found around 20-25 nm, reinforced in the matrix. Considering the results of this study, the proposed mechanical milling route can be recommended as a promising way for fabrication of TiB2/Fe-Cr-Al nanocomposite powder.</P>

        • Interfacial rheology of coexisting solid and fluid monolayers

          Sachan, A. K.,Choi, S. Q.,Kim, K. H.,Tang, Q.,Hwang, L.,Lee, K. Y.,Squires, T. M.,Zasadzinski, J. A. Royal Society of Chemistry 2017 SOFT MATTER Vol.13 No.7

          <P>Biologically relevant monolayer and bilayer films often consist of micron-scale high viscosity domains in a continuous low viscosity matrix. Here we show that this morphology can cause the overall monolayer fluidity to vary by orders of magnitude over a limited range of monolayer compositions. Modeling the system as a two-dimensional suspension in analogy with classic three-dimensional suspensions of hard spheres in a liquid solvent explains the rheological data with no adjustable parameters. In monolayers with ordered, highly viscous domains dispersed in a continuous low viscosity matrix, the surface viscosity increases as a power law with the area fraction of viscous domains. Changing the phase of the continuous matrix from a disordered fluid phase to a more ordered, condensed phase dramatically changes the overall monolayer viscosity. Small changes in the domain density and/or continuous matrix composition can alter the monolayer viscosity by orders of magnitude.</P>

        • SCIESCOPUS

          Afrocyclamin A, a triterpene saponin, induces apoptosis and autophagic cell death via the PI3K/Akt/mTOR pathway in human prostate cancer cells

          Sachan, Richa,Kundu, Amit,Jeon, Yukyoung,Choi, Wahn Soo,Yoon, Kyungsil,Kim, In Su,Kwak, Jong Hwan,Kim, Hyung Sik Elsevier 2018 Phytomedicine Vol.51 No.-

          <P><B>Abstract</B></P> <P><B>Background</B></P> <P>Afrocyclamin A, an oleanane-type triterpene saponin, was isolated from <I>Androsace umbellata</I> which used as a traditional herbal medicine.</P> <P><B>Purpose</B></P> <P>This study aimed to explore the anticancer activity of afrocyclamin A on human prostate cancer cells <I>in vitro</I> as well as <I>in vivo</I>.</P> <P><B>Methods</B></P> <P>Cytotoxicity, cell cycle distribution, apoptosis, and autophagic cell death were measured following exposure to afrocyclamin A. <I>In vivo</I> antitumor activity of afrocyclamin A was assessed in a xenograft model. The protein levels of p-Akt, p-mTOR, Bax, Bcl-2, caspase-3, and caspase-9 were quantified using western blot analysis.</P> <P><B>Results</B></P> <P>In DU145 cells, afrocyclamin A increased cytotoxicity, caused changes in cell morphology, and induced sub-G0/G1 phase indicating increased apoptosis. Afrocyclamin A robustly induced autophagic cell death as demonstrated by the conversion of LC3B-I to LC3B-II, and the formation of autophagic vacuoles as revealed by western blot analysis and fluorescence staining, respectively. Afrocyclamin A also inhibited the phosphorylation of PI3K, Akt, and mTOR, suggesting their role in afrocyclamin A induced cell death. In addition, afrocyclamin A inhibited cell migration and invasion in concentration and time-dependent manners. In an <I>in vivo</I> xenograft model, afrocyclamin A inhibited the growth of DU145 cells.</P> <P><B>Conclusion</B></P> <P>Afrocyclamin A has anticancer activity via the PI3K/Akt/mTOR pathway, which leads to cell death.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

        • KCI등재

          A New Histone Deacetylase Inhibitor, MHY4381, Induces Apoptosis via Generation of Reactive Oxygen Species in Human Prostate Cancer Cells

          ( Sachan Richa ),( Prasanta Dey ),( Chaeun Park ),( Jungho Yang ),( Ji Yeon Son ),( Jae Hyeon Park ),( Su Hyun Lee ),( Mee-young Ahn ),( In Su Kim ),( Hyung Ryong Moon ),( Hyung Sik Kim ) 한국응용약물학회 2020 Biomolecules & Therapeutics(구 응용약물학회지) Vol.28 No.2

          Histone deacetylase (HDAC) inhibitors represent a novel class of anticancer agents, which can be used to inhibit cell proliferation and induce apoptosis in several types of cancer cells. In this study, we investigated the anticancer activity of MHY4381, a newly synthesized HDAC inhibitor, against human prostate cancer cell lines and compared its efficacy with that of suberoylanilide hydroxamic acid (SAHA), a well-known HDAC inhibitor. We assessed cell viability, apoptosis, cell cycle regulation, and other biological effects in the prostate cancer cells. We also evaluated a possible mechanism of MHY4381 on the apoptotic cell death pathway. The IC<sub>50</sub> value of MHY4381 was lower in DU145 cells (IC<sub>50</sub>=0.31 µM) than in LNCaP (IC<sub>50</sub>=0.85 µM) and PC-3 cells (IC<sub>50</sub>=5.23 µM). In addition, the IC<sub>50</sub> values of MHY4381 measured in this assay were significantly lower than those of SAHA against prostate cancer cell lines. MHY4381 increased the levels of acetylated histones H3 and H4 and reduced the expression of HDAC proteins in the prostate cancer cell lines. MHY4381 increased G2/M phase arrest in DU145 cells, and G1 arrest in LNCaP cells. It also activated reactive oxygen species (ROS) generation, which induced apoptosis in the DU145 and LNCaP cells by increasing the ratio of Bax/Bcl-2 and releasing cytochrome c into the cytoplasm. Our results indicated that MHY4381 preferentially results in antitumor effects in DU145 and LNCaP cells via mitochondria-mediated apoptosis and ROS-facilitated cell death pathway, and therefore can be used as a promising prostate cancer therapeutic.

        • MABC: Power-Based Location Planning with a Modified ABC Algorithm for 5G Networks

          Sachan, Ruchi,Muhammad, Zahid,Jeong, Jaehoon (Paul),Ahn, Chang Wook,Youn, Hee Yong Hindawi Limited 2017 Discrete dynamics in nature and society Vol.2017 No.-

          <P>The modernization of smart devices has emerged in exponential growth in data traffic for a high-capacity wireless network. 5G networks must be capable of handling the excessive stress associated with resource allocation methods for its successful deployment. We also need to take care of the problem of causing energy consumption during the dense deployment process. The dense deployment results in severe power consumption because of fulfilling the demands of the increasing traffic load accommodated by base stations. This paper proposes an improved Artificial Bee Colony (ABC) algorithm which uses the set of variables such as the transmission power and location of each base station (BS) to improve the accuracy of localization of a user equipment (UE) for the efficient energy consumption at BSes. To estimate the optimal configuration of BSes and reduce the power requirement of connected UEs, we enhanced the ABC algorithm, which is named a Modified ABC (MABC) algorithm, and compared it with the latest work on Real-Coded Genetic Algorithm (RCGA) and Differential Evolution (DE) algorithm. The proposed algorithm not only determines the optimal coverage of underutilized BSes but also optimizes the power utilization considering the green networks. The performance comparisons of the modified algorithms were conducted to show that the proposed approach has better effectiveness than the legacy algorithms, ABC, RCGA, and DE.</P>

        • KCI우수등재

          Study of Serum Adipocytokines and Their Association with Insulin Sensitivity in Morbidly Obese Individuals Undergoing Bariatric Surgery

          Astha Sachan,Archna Singh,Sakshi Shukla,Sandeep Aggarwal,Ishfaq Mir,Rakhee Yadav 대한비만학회 2020 The Korean journal of obesity Vol.29 No.4

          Background: Obese adipose tissue secretes a variety of adipocytokines that act as metabolic regulators with complex mechanisms. Our objective was to compare serum concentration of a panel of adipocytokines between obese and non-obese individuals and identify any distinct patterns correlating with insulin sensitivity in obesity. Methods: We designed a cross-sectional study among obese (body mass index [BMI] ≥30 kg/m2, n=62) and non-obese (BMI <25 kg/m2, n=32) individuals to compare circulating levels of the adipokines, such as adiponectin and resistin in conjunction with the measurement of the levels of inflammatory cytokines including C-reactive protein (CRP), interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1, and tumor necrosis factor (TNF)-α using Luminex multiplex immunoassay with drop array technology. Correlations between circulating adipocytokine levels and those of multiple well-established markers of insulin resistance including homeostatic model assessment of insulin resistance (HOMA-IR), homeostatic model assessment of β-cell function (HOMA-β) and quantitative insulin sensitivity check index were also established. Results: CRP, IL-8, MCP-1, and TNF-α levels were higher in obese than non-obese individuals; the CRP and IL-8 differences were statistically significant. CRP correlated significantly with markers of insulin resistance (fasting plasma insulin, HOMA-IR, and QUICKI), and adiponectin correlated with HOMA-β in obese individuals. We divided the group of obese individuals on the basis of HOMA-IR levels into insulin-resistant (IR; HOMA-IR ≥2.5) and insulin-sensitive (IS; HOMA-IR <2.5) groups; and 43 out of 62 participants were IR despite comparable BMIs. An overall proinflammatory profile was compared between IR and IS obese, though the values were higher in IR obese but the difference was not significant. Conclusion: Obesity is associated with a general inflammatory milieu and a crosstalk between adipocytokines and insulin resistance is complex as well as multifactorial.

        • SCIESCOPUSKCI등재

          A New Histone Deacetylase Inhibitor, MHY4381, Induces Apoptosis via Generation of Reactive Oxygen Species in Human Prostate Cancer Cells

          Richa, Sachan,Dey, Prasanta,Park, Chaeun,Yang, Jungho,Son, Ji Yeon,Park, Jae Hyeon,Lee, Su Hyun,Ahn, Mee-Young,Kim, In Su,Moon, Hyung Ryong,Kim, Hyung Sik The Korean Society of Applied Pharmacology 2020 Biomolecules & Therapeutics(구 응용약물학회지) Vol.28 No.2

          Histone deacetylase (HDAC) inhibitors represent a novel class of anticancer agents, which can be used to inhibit cell proliferation and induce apoptosis in several types of cancer cells. In this study, we investigated the anticancer activity of MHY4381, a newly synthesized HDAC inhibitor, against human prostate cancer cell lines and compared its efficacy with that of suberoylanilide hydroxamic acid (SAHA), a well-known HDAC inhibitor. We assessed cell viability, apoptosis, cell cycle regulation, and other biological effects in the prostate cancer cells. We also evaluated a possible mechanism of MHY4381 on the apoptotic cell death pathway. The IC<SUB>50</SUB> value of MHY4381 was lower in DU145 cells (IC<SUB>50</SUB>=0.31 µM) than in LNCaP (IC<SUB>50</SUB>=0.85 µM) and PC-3 cells (IC<SUB>50</SUB>=5.23 µM). In addition, the IC<SUB>50</SUB> values of MHY4381 measured in this assay were significantly lower than those of SAHA against prostate cancer cell lines. MHY4381 increased the levels of acetylated histones H3 and H4 and reduced the expression of HDAC proteins in the prostate cancer cell lines. MHY4381 increased G2/M phase arrest in DU145 cells, and G1 arrest in LNCaP cells. It also activated reactive oxygen species (ROS) generation, which induced apoptosis in the DU145 and LNCaP cells by increasing the ratio of Bax/Bcl-2 and releasing cytochrome c into the cytoplasm. Our results indicated that MHY4381 preferentially results in antitumor effects in DU145 and LNCaP cells via mitochondria-mediated apoptosis and ROS-facilitated cell death pathway, and therefore can be used as a promising prostate cancer therapeutic.

        • Application Expansion inside Optimized RBF Kernel of SVM in Robust Face Recognition System

          Rakesh Kumar Yadav,Dr. AK Sachan 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.12

          Information is critical in light of the fact that it assists us take a decision. Yet, it needs security. With these worries, picture is the most ideal method for representation of data to to read, write, and and comprehend the data. Face recognition is secure since we can't change our faces, not at all like secret word signature, credit card and debit card that may be abused by others. Appearance, brightening and postures change are the significant testing issues in face acknowledgment. The unwavering quality of face recognition frameworks relies on upon limit of database of facial pictures and testing methodology to assess the face acknowledgment framework. Our examination is concerned with the testing method. This exploration proposed another algorithm of support vector machine. In Experiments we have discovered some tasteful actualities and results. It gives the most noteworthy exactness 97.9 %. This is superior to anything moderately offered results. In the most recent decade, the face recognition framework has advanced with more noteworthy than 90% recognition rate.

        • A Novel Searching Algorithm based on Reinforcement Learning

          Anil Kumar Yadav,A. K. Sachan 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.6

          We introduce an application-oriented reinforcement learning searching algorithm designed for problem with fast learning and capturing goal in less amount of time especially in robotics and games. The importance of game playing in machine learning is an exhaustive application of autonomous agent in real-world problem domain. In our previous published article represent that how autonomous agent learned through self-training and successful trained agent ready for execution [11].In this paper, we design and proposed a new application-oriented searching algorithm especially for game playing in grid world problem. In which first of all agents train all state and able to capture goal successfully. Reinforcement learning is a type of decision making system that takes decision on the basis of reward or penalty signal and learned from environment. Many games, there are no such things that follow fast learning as well as searching and genuine movement for each step. For every state action agent stored previous values in terms of q values in a look-up table. It helps for agent decision making capability during goal hitting or pray captured in the real-world game. In order to access and simulate new searching algorithms in mat lab and evaluated by comparison with different RL techniques [2, 11-12].

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