• 제목/요약/키워드: Contrast agent

검색결과 374건 처리시간 0.032초

Functional MRI를 이용한 학습집중력 향상 시트 개발 (Usefulness of Functional MRI for the study of concentration sheet)

  • 김창규
    • 한국산학기술학회논문지
    • /
    • 제10권10호
    • /
    • pp.2985-2989
    • /
    • 2009
  • 본 논문에서는 학습집중력을 향상시킬 수 있는 시트를 제작하였다. 학습집중력의 향상을 입증하기위하여 인체 내에 존재하고 있는 조영제를 이용하여 공간적 시간적 해상도가 뛰어나고 비침습적으로 뇌기능을 측정할 수 있는 기능적 자기공명영상을 획득하여 분석을 한 결과 기억작용과 관련 있는 전두엽 부근의 뇌혈류량의 활성화를 확인할 수 있었고 뇌파 측정 분석 결과 절대알파파와 절대베타파의 비율에서 유의할 만한 변화를 확인하였다. 기능적 자기공명영상은 뇌의 생리기능적 역할을 규명, 의학적으로 수술 전후 장애를 방지하고 예방하는데 활용되고 있으며 뇌신경망의 가시화로 학습집중력 향상 시트등과 같이 뇌와 관련된 제품을 개발하는데 많은 연구가 이루어질 것이다.

Computer Simulation and Verification of Adiabatic Temperature and Apparent Activity Energy of the NiO/Al Aluminothermic System

  • Song, Yuepeng;Zhu, Yanmin;Gao, Dongsheng;Guo, Jing;Kim, Hyoung Seop
    • 한국분말재료학회지
    • /
    • 제20권5호
    • /
    • pp.332-337
    • /
    • 2013
  • Recently, self-propagating high-temperature synthesis (SHS), related to metallic and ceramic powder interactions, has attracted huge interest from more and more researchers, because it can provide an attractive, energy-efficient approach to the synthesis of simple and complex materials. The adiabatic temperature $T_{ad}$ and apparent activation energy analysis of different thermit systems plays an important role in thermodynamic studies on combustion synthesis. After establishing and verifying a mathematic calculation program for predicting adiabatic temperatures, based on the thermodynamic theory of combustion synthesis systems, the adiabatic temperatures of the NiO/Al aluminothermic system during self-propagating high-temperature synthesis were investigated. The effect of a diluting agent additive fraction on combustion velocity was studied. According to the simulation and experimental results, the apparent activation energy was estimated using the Arrhenius diagram of $ln(v/T_{ad}){\sim}/T_{ad}$ based on the combustion equation given by Merzhanov et al. When the temperature exceeds the boiling point of aluminum (2,790 K), the apparent activation energy of the NiO/Al aluminothermic system is $64{\pm}14$ kJ/mol. In contrast, below 2,790 K, the apparent activation energy is $189{\pm}15$ kJ/mol. The process of combustion contributed to the mass-transference of aluminum reactant of the burning compacts. The reliability of the simulation results was experimentally verified.

Rhus verniciflua Stokes extract suppresses migration and invasion in human gastric adenocarcinoma AGS cells

  • Lee, Hyun Sook;Jung, Jae In;Kim, Kyeong-Hee;Park, Sang Jae;Kim, Eun Ji
    • Nutrition Research and Practice
    • /
    • 제14권5호
    • /
    • pp.463-477
    • /
    • 2020
  • BACKGROUND/OBJECTIVES: Many studies have suggested that Rhus verniciflua Stokes (RVS) and its extract are anticancer agents. However, RVS had limited use because it contains urushiol, an allergenic toxin. By improving an existing allergen-removal extraction method, we developed a new allergen-free Rhus verniciflua Stokes extract (RVSE) with higher flavonoid content. In this study, we examined whether RVSE inhibits the ability of AGS gastric cancer cells to migrate and invade. MATERIALS/METHODS: The flavonoids content of RVSE was analyzed by HPLC. The effects of RVSE on migration and invasion in AGS cells were analyzed by each assay kit. Matrix metalloproteinase (MMP)-9, plasminogen activator inhibitor-1 (PAI-1) and urokinase-type plasminogen activator (uPA) protein expression was analyzed by protein antibody array. The Phosphorylation of signal transducer and activator of transcription (STAT) 3 were assayed by Western blot analysis. RESULTS: RVSE treatment with 0-100 ㎍/mL dose-dependently reduced the ability of AGS cells to migrate and invade. Notably, treatment with RVSE strongly inhibited the expression of MMP-9 and uPA and the phosphorylation of STAT3. In contrast, RVSE treatment dramatically increased the expression of PAI-1. These results indicate that the inhibition of MMP-9 and uPA expression and STAT3 phosphorylation and the stimulation of PAI-1 expression contributed to the decreased migration and invasion of AGS cells treated with RVSE. CONCLUSIONS: These results suggest that RVSE may be used as a natural herbal agent to reduce gastric cancer metastasis.

남해안 어류양식장에서 분리 된 Enterococcus Faecalis와 E. faecium의 항균제 감수성 비교 (Antimicrobial Susceptibility Pattern of Enterococcus faecalis and E. faecium from Fish Farms in the Southern Coast of Korea)

  • 오은경;손광태;유홍식;김지회;이태식;이희정
    • 한국수산과학회지
    • /
    • 제41권6호
    • /
    • pp.435-439
    • /
    • 2008
  • The antimicrobial resistance of 160 strains of Enterococcus faecalis and 173 strains of E. faecium to 12 antimicrobial agents was investigated. The test strains were isolated from 126 wild seawater and farmed fish, including olive flounder (Paralichthys olivaceus), black rock fish (Sebastes schlegeli), red sea bream (Pagrus major), and sea bass (Lateolabrax japonicus), in 2005 and 2006. Overall, 91.9% of the E. faecalis isolates and 88.4% of the E. faecium isolates showed antimicrobial resistance to at least one antimicrobial agent. The pattern of antimicrobial resistance of the isolates differed little according to the species of fish. The percentage of E. faecalis and E. faecium with specific antimicrobial resistance differed according to the sample source. For the isolates from farmed fish samples, 66.7% of E. faecalis were tetracycline resistant and 54.5% of E. faecium were erythromycin resistant. By contrast, in the wild fish seawater samples, 92.0% of E. faecalis were rifampin resistant and 88.5% of E. faecium were tetracycline resistant.

인후두역류질환 (Laryngopharyngeal Reflux Disease, LPRD)에서 Rabeprazole Sodium($Pariet^{\circledR}$)의 임상효과 (The clinical effects of rabeprazole sodium($Pariet^{\circledR}$) in the treatment of Layngopharyngeal Reflux)

  • 최홍식;최현승;김한수
    • 대한기관식도과학회지
    • /
    • 제9권1호
    • /
    • pp.60-66
    • /
    • 2003
  • Although there is a wide range of diseases caused by gastric acid reflux and the number of cases is on the rise, it is difficult for the laryngologist to make the correct diagnosis. The treatment for laryngopharyngeal reflux can be grouped into 3 categories - changes in lifestyle, medication, and surgery. The medication used to treat laryngopharyngeal reflux are prokinetic agents and acid supressive agents such as antacids, H2 blockers, and PPIs(Proton pump inhibitor). Rabeprazole sodium($Pariet^{\circledR}$) is a newly developed agent belonging to the PPI group, but in contrast with the existing drugs such as omeprazole, lansoprazole, pantoprazole, has a low dependency on CYP2C19 during the metabolic cycle. Thus, it is known to have a quick but fixed antiacid effect and less individual differences. We analyzed 2166 patients from 32 hospitals who were prescribed $Pariet^{\circledR}$ from May, 2001 to April, 2002. The patients were divided into 4 groups according to the duration of treatment - Group 1: 1-14 days, Group 2: 15-28 days, group 3: 29-56 days, Group 4: more than 56 days. The cases were then analyzed for improvement of 8 symptoms(heart bum, regurgitation, chronic cough, hoarseness, globus sensation, chronic throat clearing, sore throat, and dysphagia), improvement on laryngoscope, usefulness to the doctor, and complication development. Of the total of 2116 patients, 1627(75.1%) cases showed at least 50% improvement of symptoms and the amount of improvement increased according to the duration of medical treatment. Most of the patients showed objective improvement on the laryngoscope, with 32.9% showing significant improvement and 38.7% showing moderate improvement. 37.6% of the doctors questioned replied that $Pariet^{\circledR}$ was very useful and 50.3% said it was useful, showing that most were satisfied with the treatment results. The complications known to develop after taking PPI are headache, nausea, diarrhea, abdominal pain, constipation, dizziness, fatigue, and of these, only a small percentage of the patients complained of mild headache. $Pariet^{\circledR}$ has shown to be a relatively safe and effective drug for the treatment of laryngopharyngeal reflux.

  • PDF

Gomisin G Inhibits the Growth of Triple-Negative Breast Cancer Cells by Suppressing AKT Phosphorylation and Decreasing Cyclin D1

  • Maharjan, Sony;Park, Byoung Kwon;Lee, Su In;Lim, Yoonho;Lee, Keunwook;Kwon, Hyung-Joo
    • Biomolecules & Therapeutics
    • /
    • 제26권3호
    • /
    • pp.322-327
    • /
    • 2018
  • A type of breast cancer with a defect in three molecular markers such as the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor is called triple-negative breast cancer (TNBC). Many patients with TNBC have a lower survival rate than patients with other types due to a poor prognosis. In this study, we confirmed the anti-cancer effect of a natural compound, Gomisin G, in TNBC cancer cells. Treatment with Gomisin G suppressed the viability of two TNBC cell lines, MDA-MB-231 and MDA-MB-468 but not non-TNBC cell lines such as MCF-7, T47D, and ZR75-1. To investigate the molecular mechanism of this activity, we examined the signal transduction pathways after treatment with Gomisin G in MDA-MB-231 cells. Gomisin G did not induce apoptosis but drastically inhibited AKT phosphorylation and reduced the amount of retinoblastoma tumor suppressor protein (Rb) and phosphorylated Rb. Gomisin G induced in a proteasome-dependent manner a decrease in Cyclin D1. Consequently, Gomisin G causes cell cycle arrest in the G1 phase. In contrast, there was no significant change in T47D cells except for a mild decrease in AKT phosphorylation. These results show that Gomisin G has an anti-cancer activity by suppressing proliferation rather than inducing apoptosis in TNBC cells. Our study suggests that Gomisin G could be used as a therapeutic agent in the treatment of TNBC patients.

A Novel Trp-rich Model Antimicrobial Peptoid with Increased Protease Stability

  • Bang, Jeong-Kyu;Nan, Yong-Hai;Lee, Eun-Kyu;Shin, Song-Yub
    • Bulletin of the Korean Chemical Society
    • /
    • 제31권9호
    • /
    • pp.2509-2513
    • /
    • 2010
  • In order to increase protease stability of a novel Trp-rich model antimicrobial peptide, $K_6L_2W_3$ (KLWKKWKKWLK-$NH_2$)and investigate the effect of L-amino acid to peptoid residue conversion on biological functions, we synthesized its antimicrobial peptoid, $k_6l_2w_3$. Peptoid $k_6l_2w_3$ had similar bacterial selectivity compared to peptide $k_66L_2W_3$. The bactericidal rate of $k_6l_2w_3$ was somewhat slower than that of $K_6L_2W_3$. Peptoid $k_6l_2w_3$ exhibited very little dye leakage from bacterial outer-membrane mimicking PE/PG liposomes, as observed in $K_6L_2W_3$, indicating that the major target site of $K_6L_2W_3$ and $k_6l_2w_3$ may be not the cell membrane but the cytoplasm of bacteria. Trypsin treatment of $K_6L_2W_3$ completely abolished antimicrobial activities against Escherichia coli and Staphylococcus aureus. In contrast, the antimicrobial activity of $k_6l_2w_3$ was completely preserved after trypsin treatment. Taken together, our results suggested that antimicrobial peptoid $k_6l_2w_3$ can potentially serves as a promising therapeutic agent for the treatment of microbial infection.

사람구강편평상피암세포에서 유지놀에 의한 세포자멸사 유도 효과 (The effect of eugenol on the induction of apoptosis in HSC-2 human oral squamous cell carcinoma)

  • 김용호;박봉수
    • 한국치위생학회지
    • /
    • 제15권3호
    • /
    • pp.523-529
    • /
    • 2015
  • Objectives: Oropharynx tumors(oral cancer), are caused by tobacco, alcohol consumption, and high-risk human papillomavirus(HPV) infection. Oral squamous cell carcinoma(OSCC) is the most common type of oral cancer and frequently arises from the mucosa of the oropharynx and oral cavity. Despite advances in the diagnosis and treatment(chemotherapy, radiotherapy, and surgery) of oral cancer, over the past two decades, the overall survival rates remains at about 60%. Methods: We pretreated HSC-2 cells with various doses of exposed the cells to eugenol and then we measured cell viability by MTT assay. Results: Cell proliferation was markedly inhibited after eugenol treatment compared to the control. The majority of HSC-2 cells in the control groups showed normal morphology with round regular nuclei. In contrast, apoptotic bodies were seen in the 0.5 mM, 1 mM, 2 mM group. However, the pretreatment with eugenol increased HSC-2 cells apoptosis according to dose-dependency. PI staining quantitatively confirmed the anti-apoptotic effects of propofol. The expression levels of cleaved caspase 3, and Bak significantly increased in HSC-2 cells. Conclusions: These findings indicate that eugenol could be a potential anti-cancer agent for human OSCC and provide valuable data for the development of a novel anticancer strategy.

돌외 에탄올 추출물 엑스의 만성 스트레스-유도 불안작용에 대한 개선작용 (Ameliorating Effects of Herbal Ethanol Extract from Gynostemma pentaphyllum on Chronic Stress-Induced Anxiety in Mice)

  • 최현숙;신건성;최순옥;김승환;황방연;이종길;이명구
    • 생약학회지
    • /
    • 제42권1호
    • /
    • pp.32-37
    • /
    • 2011
  • The effects of herbal ethanol extract from Gynostemma pentaphyllum (GP extract) on chronic stress-induced anxiety in mice were investigated. The animals were treated with GP extracts (50 and 100 mg/kg/day, p.o.) for 21 days before exposure to electric footshock (EF; duration and interval 10 sec for 3 min, 2 mA) for chronic stress once a day. The ambulatory locomotor activity was reduced by chronic EF stress and it was recovered by 12.9-15.1% in GP extract-treated groups. The grip strength was also significantly decreased by chronic EF stress, however, the EF-stressed groups treated with GP extract increased grip strength from 13.9% to 56.8% compared to EF-stressed groups. In addition, the serum levels of corticosterone were significantly elevated by chronic EF stress to 197% of the control levels, which was reduced to 73.1% by treatment with GP extract (100 mg/kg). In contrast, the brain levels of dopamine and serotonin were reduced to 67.6% and 63.1% by chronic EF stress, which was recovered to 90% of the control levels by treatment with GP extract. These results indicate that GP extract shows the ameliorating effects on chronic EF stress-induced anxiety in mice and it can be developed as the promising anti-anxiety agent.

칠피(漆皮) 추출물의 담도암 세포주 SNU-1079와 SNU-1196에 대한 항암효과 (Study on Anti-Cancer Effects of Rhus Verniciflua Stokes Extracted with Sterile Distilled Water on Two Cholangiocarcinoma Cell Lines, SNU-1079 and SNU-1196)

  • 정보배;김영철
    • 대한한방내과학회지
    • /
    • 제36권1호
    • /
    • pp.1-12
    • /
    • 2015
  • Objectives : This study was performed to investigate the anti-cancer effects of Rhus verniciflua Stokes (RVS) extracted with sterile distilled water on cholangiocarcinoma cell lines. Materials and Methods : Two cholangiocarcinoma cell lines, SNU-1079 and SNU-1196, were used in this study. Cells were treated with different concentrations of RVS for 24, 48, and 72 hours. Cell count, viability, apoptosis, and mRNA expression of Bax, Bcl-2, Mcl-1, survivin, caspase-3, and cyclin D1 and P21 were determined with an automatic cell counter (ADAM-MC), MTT assay, apoptosis assay (Annexin-V/PI staining), and RT-PCR. Results : All cells treated with RVS showed decreased cell counts in a dose-dependent manner. RVS inhibited proliferation of SNU-1196 in a dose-dependent manner, but SNU-1079 proliferation was inhibited in the long-time culture group in a dose-dependent manner. The proportion of early and late-stage apoptotic cells was increased by RVS in a dose-dependent manner in SNU-1196. In contrast, it was increased significantly in SNU-1079 treated with high-dose RVS. After treatment with RVS, the mRNA expression of Bcl-2 was decreased while Bax was increased in SNU-1079. Cyclin D1 mRNA levels were decreased in SNU-1196 in a dose-dependent manner. P21 expression was increased in all cells after the treatment with RVS. Conclusions : RVS appears to have potential as a therapeutic agent for cholangiocarcinoma.