• Title/Summary/Keyword: Biomedical technology

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Self-Assembled Nanoparticles of Bile Acid-Modified Glycol Chitosans and Their Applications for Cancer Therapy

  • Kim Kwangmeyung;Kim Jong-Ho;Kim Sungwon;Chung Hesson;Choi Kuiwon;Kwon Ick Chan;Park Jae Hyung;Kim Yoo-Shin;Park Rang-Won;Kim In-San;Jeong Seo Young
    • Macromolecular Research
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    • v.13 no.3
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    • pp.167-175
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    • 2005
  • This review explores recent works involving the use of the self-assembled nanoparticles of bile acid-modified glycol chitosans (BGCs) as a new drug carrier for cancer therapy. BGC nanoparticles were produced by chemically grafting different bile acids through the use of l-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). The precise control of the size, structure, and hydrophobicity of the various BGC nanoparticles could be achieved by grafting different amounts of bile acids. The BGC nanoparticles so produced formed nanoparticles ranging in size from 210 to 850 nm in phosphate-buffered saline (PBS, pH=7.4), which exhibited substantially lower critical aggregation concentrations (0.038-0.260 mg/mL) than those of other low-molecular-weight surfactants, indicating that they possess high thermodynamic stability. The SOC nanoparticles could encapsulate small molecular peptides and hydrophobic anticancer drugs with a high loading efficiency and release them in a sustained manner. This review also highlights the biodistribution of the BGC nanoparticles, in order to demonstrate their accumulation in the tumor tissue, by utilizing the enhanced permeability and retention (EPR) effect. The different approaches used to optimize the delivery of drugs to treat cancer are also described in the last section.

TRAPR: R Package for Statistical Analysis and Visualization of RNA-Seq Data

  • Lim, Jae Hyun;Lee, Soo Youn;Kim, Ju Han
    • Genomics & Informatics
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    • v.15 no.1
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    • pp.51-53
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    • 2017
  • High-throughput transcriptome sequencing, also known as RNA sequencing (RNA-Seq), is a standard technology for measuring gene expression with unprecedented accuracy. Numerous bioconductor packages have been developed for the statistical analysis of RNA-Seq data. However, these tools focus on specific aspects of the data analysis pipeline, and are difficult to appropriately integrate with one another due to their disparate data structures and processing methods. They also lack visualization methods to confirm the integrity of the data and the process. In this paper, we propose an R-based RNA-Seq analysis pipeline called TRAPR, an integrated tool that facilitates the statistical analysis and visualization of RNA-Seq expression data. TRAPR provides various functions for data management, the filtering of low-quality data, normalization, transformation, statistical analysis, data visualization, and result visualization that allow researchers to build customized analysis pipelines.

Interleukin-$32{\gamma}$ Transgenic Mice Resist LPS-Mediated Septic Shock

  • Kim, Sun Jong;Lee, Siyoung;Kwak, Areum;Kim, Eunsom;Jo, Seunghyun;Bae, Suyoung;Lee, Youngmin;Ryoo, Soyoon;Choi, Jida;Kim, Soohyun
    • Journal of Microbiology and Biotechnology
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    • v.24 no.8
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    • pp.1133-1142
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    • 2014
  • Interleukin-32 (IL-32) is a cytokine and inducer of various proinflammatory cytokines such as $TNF{\alpha}$, IL-$1{\beta}$, and IL-6 as well as chemokines. There are five splicing variants (${\alpha}$, ${\beta}$, ${\gamma}$, ${\delta}$, and ${\varepsilon}$) and IL-$32{\gamma}$ is the most active isoform. We generated human IL-$32{\gamma}$ transgenic (IL-$32{\gamma}$ TG) mice to express high level of IL-$32{\gamma}$ in various tissues, including immune cells. The pathology of sepsis is based on the systemic inflammatory response that is characterized by upregulating inflammatory cytokines in whole body, particularly in response to gram-negative bacteria. We investigated the role of IL-$32{\gamma}$ in a mouse model of experimental sepsis by using lipopolysaccharides (LPS). We found that IL-$32{\gamma}TG$ mice resisted LPS-induced lethal endotoxemia. IL-$32{\gamma}$ reduced systemic cytokines release after LPS administration but not the local immune response. IL-$32{\gamma}TG$ increased neutrophil influx into the initial foci of the primary injected site, and prolonged local cytokines and chemokines production. These results suggest that neutrophil recruitment in IL-$32{\gamma}TG$ occurred as a result of the local induction of chemokines but not the systemic inflammatory cytokine circulation. Together, our results suggest that IL-$32{\gamma}$ enhances an innate immune response against local infection but inhibits the spread of immune responses, leading to systemic immune disorder.

Immunoglobulin G4-Related Disease in the Diaphragm: A Case Report (횡격막에 발생한 면역글로불린 G4 연관 질환: 증례 보고)

  • Jin Woo Kim;Taehwa Kim;Kun-Il Kim;Yeon Joo Jeong;Dohyung Kim;Dong Hoon Shin;Yun Seong Kim
    • Journal of the Korean Society of Radiology
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    • v.85 no.5
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    • pp.954-959
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    • 2024
  • Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated condition characterized by mass-forming inflammation with a sclerosing pattern that can affect nearly any organ. However, involvement of the diaphragm in IgG4-RD is exceptionally rare. We present the case of a 62-year-old male patient with chest radiographic abnormalities. Further investigation with CT revealed an infiltrative mass in the right hemidiaphragm. This mass, composed of engorged feeding vessels, an atypical manifestation of IgG4-RD, was also associated with lymphadenopathy. Surgical excision confirmed the presence of IgG4-positive cell infiltration, solidifying the diagnosis of IgG4-RD. Notably, the patient remained asymptomatic and did not require any treatment postoperatively. This case highlights the uncommon presentation of IgG4-RD as an infiltrative diaphragmatic mass.

Precise ultrasonic coating and controlled release of sirolimus with biodegradable polymers for drug-eluting stent

  • Joung, Yoon Ki;Jang, Bu Nam;Kang, Jong Hee;Han, Dong Keun
    • Biomaterials and Biomechanics in Bioengineering
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    • v.1 no.1
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    • pp.13-25
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    • 2014
  • In the current study, a drug-eluting stent coated with biodegradable polymers and sirolimus was developed by using an ultrasonic nanocoater and characterized in aspects of surface smoothness and coating thickness. In addition, in vitro release profiles of sirolimus by changing top coating layer with different biodegradable polymers were investigated. Smooth surfaces with variable thickness could be fabricated by optimizing polymer concentration, flow rate, nozzle-tip distance, gas pressure, various solvents and ultrasonic power. Smooth surface could be generated by using volatile solvents (acetone, chloroform, and methylene chloride) or post-treating with solvent vapor. Coating thickness could be controlled by varying injection volume or polymer concentration, and higher concentration could reduce the coating time while obtaining the same thickness. The thickness measurement was the most effectively performed by a conventional cutting method among three different methods that were investigated in this study. Release profiles of sirolimus were effectively controlled by changing polymers for top layer. PLGA made the release rate 3 times faster than PDLLA and PLLA and all top layers prevented burst release at the initial phase of profiles. Our results will provide useful and informative knowledge for developing drug-eluting stents, especially coated with biodegradable polymers.

Biphasic Tumor Oxygenation during Respiratory Challenge may Predict Tumor Response during Chemotherapy

  • Lee, Songhyun;Jeong, Hyeryun;Anguluan, Eloise;Kim, Jae Gwan
    • Current Optics and Photonics
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    • v.2 no.1
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    • pp.1-6
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    • 2018
  • Our previous study showed that switching the inhaled gas from hypoxic gas to hyperoxic gas for 10 minutes increased tumor oxygenation and that the magnitude of oxyhemoglobin increase responded earlier than tumor volume change after chemotherapy. During 10 minutes of inhaled-oxygen modulation, oxyhemoglobin concentration first shows a rapid increase and then a slow but gradual increase, which has been fitted with a double-exponential equation in this study. Two amplitude values, amplitudes 1 and 2, respectively represent the magnitudes of rapid and slow increase of oxyhemoglobin. The trends of changes in amplitudes 1 and 2 were different, depending on tumor volume when chemotherapy started. However, both amplitudes 1 and 2 changed earlier than tumor volume, regardless of when chemotherapy was initiated. These results imply that by observing amplitude 1 changes post chemotherapy, we can reduce the time of a respiratory challenge from 10 minutes to less than 2 minutes, to see the chemotherapy response. We believe that by reducing the time of the respiratory challenge, we have taken a step forward to translating our previous study into clinical application.

Estrogen receptor β stimulates Egr-1 transcription via MEK1/Erk/Elk-1 cascade in C6 glioma cells

  • Kim, Ji-Ha;Jeong, Il-Yeup;Lim, Yoong-Ho;Lee, Young-Han;Shin, Soon-Young
    • BMB Reports
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    • v.44 no.7
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    • pp.452-457
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    • 2011
  • The Egr-1 is an immediate early response gene encoding a transcription factor that functions in the regulation of cell growth, differentiation, and apoptosis. Estrogen has diverse physiological effects, including cellular proliferation and neuroprotection against brain injury. There are two types of estrogen receptors (ERs), $ER{\alpha}$ and $ER{\beta}$. $ER{\alpha}$-induced Egr-1 expression has been extensively studied; however, the role of $ER{\beta}$ is yet not known. In the present study, we investigated whether or not $ER{\beta}$ induces Egr-1 expression in C6 rat glioma cells, which express $ER{\beta}$ but not $ER{\alpha}$. Our results show that $ER{\beta}$ promoted up-regulation of Egr-1 expression via a non-genomic mechanism involving the Raf/MEK1/Erk/Elk-1 signaling cascade.

Doxorubicin Binds to Un-phosphorylated Form of hNopp140 and Reduces Protein Kinase CK2-Dependent Phosphorylation of hNopp140

  • Kim, Yun-Kyoung;Lee, Won-Kyu;Jin, Young-nam;Lee, Kong-Joo;Jeon, Hye-sung;Yu, Yeon-Gyu
    • BMB Reports
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    • v.39 no.6
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    • pp.774-781
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    • 2006
  • Human nucleolar phosphoprotein p140 (hNopp140) is a nucleolar phosphoprotein that can bind to doxorubicin, an anti-cancer agent. We have examined the interaction between hNopp140 and doxorubicin as well as the folding property of hNopp140. Also, the effects of ATP and phosphorylation on the affinity of hNopp140 to doxorubicin are investigated by affinity dependent co-precipitation and surface plasmon resonance methods. Doxorubicin preferentially binds to un-phosphorylated form of hNopp140 with a $K_D$ value of $3.3\;{\times}\;10^{-7}$ M. Furthermore, doxorubicin reduces the protein kinase CK2-dependent phosphorylation of hNopp140, indicating that doxorubicin may perturb the cellular function of hNopp140 by reducing the protein kinase CK2-dependent phosphorylation of hNopp140. Low contents of the secondary structures of hNopp140 and the fast rate of proteolysis imply that hNopp140 has a high percentage of flexible regions or extended loop structures.