• Title/Summary/Keyword: chain elongation

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Gemcitabine in Treating Patients with Refractory or Relapsed Multiple Myeloma

  • Zheng, Hua;Yang, Fan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9291-9293
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    • 2014
  • Background: Patients with refractory or relapsed multiple myeloma are considered to have a very poor prognosis, and new regimens are needed to improve the outcome. Gemcitabine, a nucleoside antimetabolite, is an analog of deoxycytidine which mainly inhibits DNA synthesis through interfering with DNA chain elongation and depleting deoxynucleotide stores, resulting in gemcitabine-induced cell death. Here we performed a systemic analysis to evaluate gemcitabine based chemotherapy as salvage treatment for patients with refractory and relapsed multiple myeloma. Methods: Clinical studies evaluating the impact of gemcitabine based regimens on response and safety for patients with refractory and relapsed multiple myeloma were identified by using a predefined search strategy. Pooled response rate (RR) of treatment were calculated. Results: In gemcitabine based regimens, 3 clinical studies which including 57 patients with refractory and relapsed multiple myeloma were considered eligible for inclusion. Systemic analysis suggested that, in all patients, pooled RR was 15.7% (9/57) in gemcitabine based regimens. Major adverse effects were hematologic toxicity, including grade 3 or 4 anemia, leucopenia and thrombocytopenia i. No treatment related death occurred with gemcitabine based treatment. Conclusion: This systemic analysis suggests that gemcitabine based regimens are associated with mild activity with good tolerability in treating patients with refractory or relapsed multiple myeloma.

Gemcitabine for the Treatment of Patients with Osteosarcoma

  • Wei, Mei-Yang;Zhuang, Yan-Feng;Wang, Wan-Ming
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.17
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    • pp.7159-7162
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    • 2014
  • Background: Patients with recurrent or refractory osteosarcoma are considered to have a very poor prognosis, and new regimens are needed to improve the prognosis in this setting. Gemcitabine, a nucleoside antimetabolite, is an analog of deoxycytidine which mainly inhibits DNA synthesis through interfering with DNA chain elongation and depleting deoxynucleotide stores, resulting in gemcitabine-induced cell death. Here we performed a systemic analysis to evaluate gemcitabine based chemotherapy as salvage treatment for patients with recurrent or refractory osteosarcoma. Methods: Clinical studies evaluating the impact of gemcitabine based regimens on response and safety for patients with osteosarcoma were identified by using a predefined search strategy. Pooled response rates (RRs) of treatment were calculated. Results: In gemcitabine based regimens, 4 clinical studies which included 66 patients with recurrent or refractory osteosarcoma were considered eligible for inclusion. Systemic analysis suggested that, in all patients, pooled RR was 12.1% (8/66) in gemcitabine based regimens. Major adverse effects were hematologic toxicity, including grade 3 or 4 anemia, leucopenia and thrombocytopenia in gemcitabine based treatment. No treatment related death occurred in gemcitabine based treatment. Conclusion: This systemic analysis suggests that gemcitabine based regimens are associated with mild activity with good tolerability in treating patients with recurrent or refractory osteosarcoma.

Mechanical Properties and Synthesis of Polyurethane Dispersion by Glycerol for Vegetable Leather Surface Coatings (Vegetable Leather 표면코팅에 대한 Glycerol을 이용한 수분산 폴리우레탄의 합성 및 기계적 특성)

  • Lee, Joo-Youb
    • Journal of the Korean Applied Science and Technology
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    • v.32 no.1
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    • pp.100-107
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    • 2015
  • Prepared polyurethane resin for vegetable leather coating on surface was synthesized with glycerol which had different mole ratio. Mechanical properties of the synthesized polyurethane resin were measured by the SEM, FT-IR, UTM. Growing concerns in the evnironment-friendly polymer resin, we have synthesized low late obtained solvent water dispersion resin to be coating on vegetable leather. The increase of aliphatic trihydric alcohol glycerol mole %, abrasion resistance and tensile strength had highly stronger in intensity and longer durability. On the contrary, demonstrated reduce properties of elongation and flexibility. In the result of toluene solvent resistance, there was no effect of increased or decreased by the ratio of glycerol mole %.

The Mechanical Properties and Alkali Hydrolysis on Composition Ratio of Nylon 6-Polyester Split-type Yarn (Nylon 6-Polyester 조성비에 따른 분할사의 알칼리 분해거동과 물성 변화)

  • Park, Myung Soo
    • Textile Coloration and Finishing
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    • v.26 no.4
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    • pp.331-338
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    • 2014
  • In this research, split-type complex yarn of 20:80, 40:60, 50:50 nylon6/polyester composition ratio was used in order to impose unique sense on split-type complex woven. After treating both split-type complex yarn of each ratio and its produced woven in alkali solution, we got the following results by checking physical properties based on alkali proportion and treatment time. Under the condition of NaOH 20% in this experiment, it took approximately double time 20% loss of weight. The loss of weight became high when polyester proportion of N/P(nylon6/polyester) composition ratio was low, in the same fineness yarn. Even though polyester proportion was low, the loss of weight was low when the fineness was high. N/P division was well processed at about 25% loss of weight under the condition of NaOH 20%, treatment temperature $50^{\circ}C$, and treatment time 60 minutes. The research provides that the loss of weight should be processed around treatment time 24 hours in the case of NaOH concentration 15%, and treatment time 15 hours in the case of NaOH concentration 18%, respectively, in order to achieve N/P woven division ratio of about 70%-80% in industrial fields.

Effect of Low Doses of Genistein and Equol on Protein Expression Profile in MCF-7 Cells

  • Kim, Jang-Hoon;Lim, Hyun-Ae;Lee, Jeong-Soon;Sung, Mi-Kyung;Kim, Young-Kyoon;Yu, Ri-Na;Kim, Jong-Sang
    • Food Science and Biotechnology
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    • v.14 no.6
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    • pp.854-859
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    • 2005
  • Although action modes of equol and genistein have been extensively studied, their precise roles in tumor cells remain elusive. To address possible effects of these compounds on protein expression in mammary tumor cells, proteins modulated in MCF-7 mammary tumor cells when incubated in absence and presence of 10 uM equol or genistein were identified through 2-dimensional gel electrophoresis, MALDI-TOF MS/MS, and NCBInr database search using Mascot software. Most proteins differentially expressed in MCF-7 cells after treatment with 10 uM genistein or equol were identified as being the same. Exposure to both compounds caused decreased cellular expression of RNA-binding protein regulatory subunit and oncogene DJ1 tubulin beta-1 chain, and increased expression of heterogeneous ribonucleoproteins F and L, KH-type splicing regulatory protein, and translation elongation factor EF-Tu precursor. Genistein and equol at dose used in this study showed common action mechanism.

Property Enhancement of SiR-EPDM Blend Using Electron Beam Irradiation

  • Deepalaxmi, R.;Rajini, V.
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.984-990
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    • 2014
  • Polymers are the most commonly used di-electrics because of their reliability, availability, ease of fabrication and cost. The commercial and industrial demand for advanced polymeric materials which are capable of being used in harsh environment is need of the hour. The study of the effect of electron beam irradiation on polymeric materials is an area of rapidly increasing interest. This paper discusses the resultant beneficial effects of electron beam irradiation on the SiR-EPDM blend having 50:50 composition. The changes in mechanical and electrical properties of SiR-EPDM blend which are exposed to three different doses of electron beam radiation namely 5 Mrad, 15 Mrad and 25 Mrad are presented. The irradiated blends are analyzed for their electro-mechanical and physico chemical properties. The electrical changes induced by irradiation are investigated by arc resistance, surface resistivity and volume resistivity measurements as per ASTM standards. The mechanical changes are observed by the measurement of tensile strength and elongation at break. Physico chemical investigation has been done using the FTIR, in order to investigate the irradiation induced chemical changes.

Expression of Acid Stress-Induced Proteins of Streptococcus mutans Isolated from Korean Children with Caries (한국인 우식아동으로부터 분리한 Streptococcus mutans의 내산성 단백질의 발현)

  • Kang, Kyung-Hee;Nam, Jin-Sik;Jin, Ing-Nyol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.7
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    • pp.1766-1772
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    • 2009
  • In this study, we are interested in comparing the protein profiles of acid-shocked and control cells of S. mutans isolated from Korean children with caries. The results of 2D gel electrophoresis showed that twelve proteins are up-regulated when the cells were grown under 20 mM lactic acid stress in the exponential phase. Up-proteins under acid stress were estimated a major key of the survival and proliferation of S. mutans in low pH environments. These proteins are estimated generally associated with three biochemical pathways: glycolysis, alternative acid production and branched-chain amino acid biosynthesis.

Synthesis and Properties of Bio-Thermoplastic Polyurethanes with Different Isocyanate Contents

  • Li, Xiang Xu;Sohn, Mi Hyun;Cho, Ur Ryong
    • Elastomers and Composites
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    • v.54 no.3
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    • pp.225-231
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    • 2019
  • Bio-based polyester polyol was synthesized via esterification between azelaic acid and isosorbide. After esterification, bio-based polyurethanes were synthesized using polyester polyol, 1,3-propanediol as the chain extender, and 4,4'-diphenylmethane diisocyanate, in mixing ratios of 1:1:1.5, 1:1:1.8, 1:1:2, and 1:1:2.3. The bio TPU (Thermoplastic Polyurethane) samples were characterized by using FT-IR (Fourier Transform Infrared Spectroscopy), TGA (Thermal Gravimetric Analysis), DSC (Differential Scanning Calorimetry), and GPC (Gel Permeation Chromatography). The mechanical properties (tensile stress and hardness) were obtained by using UTM, a Shore A tester, and a Taber abrasion tester. The viscoelastic properties were tested by an Rubber Processing Analyzer in dynamic strain sweep and dynamic frequency test modes. The chemical resistance was tested with methanol by using the swelling test method. Based on these results, the bio TPU synthesized with the ratio of 1:1:2.3, referred to as TPU 4, showed the highest thermal decomposition temperature, the largest molecular weight, and most compact matrix structure due to the highest ratio of the hard segment in the molecular structure. It also presented the highest tensile strength, the largest elongation, and the best viscoelastic properties among the different bio TPUs synthesized herein.

Preparation and Physical Properties of Biodegradable High Performance PLA Fiber using Process Parameters (용융방사에 의한 생분해성 고강도 PLA 섬유 제조 공정 상 주요 공정 변수에 관한 연구)

  • Jeung, Woo Chang;Kim, Sam Soo;Lee, Sang Oh;Lee, Jaewoong
    • Textile Coloration and Finishing
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    • v.34 no.3
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    • pp.197-206
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    • 2022
  • The purpose of this study was to confirm the optimal spinning conditions for PLA (Polylactic acid) as a fiber forming polymer. According to the melt spinning test results of PLA, the optimal spinning temperature was 258℃. However, it needs to note that relatively high pack pressure was required for spinning at 258℃. At an elevated temperature, 262℃, mono filament was broken easily due to hydrolysis of PLA at a higher temperature. In case of fiber strength, it was confirmed that the draw ratios of 2.7 to 3.3 were optimal for maximum strength of melt spun PLA. Above the draw ratio, 3.3, the strength of the PLA fibers was lowered. It was presumed that cleavage of the PLA polymer chain over maximum elongation. The heat setting temperature of GR (Godet roller) showed that the maximum strength of the PLA fibers was revealed around 100℃. The degree of crystallinity and the strength of the PLA fibers were decreased above 100℃. The optimal take-up speed (Spinning speed) was around 4,000m/min. Thermal analysis of PLA showed 170℃ and 57℃ as Tm (melting temperature) and Tg (glass transition temperature), respectively.

Evaluation of brass weaving fishing nets for aquaculture cage applications (어류 가두리에 적용하기 위한 황동 직조 어망의 성능 평가)

  • Geon Woo KIM;Subong PARK
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.60 no.2
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    • pp.186-193
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    • 2024
  • Most fishing nets used in fish cage aquaculture are made of synthetic fibers such as polyamide (PA) and polyethylene (PE). Therefore, it is challenging to maintain the internal volume of the fish cage due to biofouling, which can increase the load on the cage or reduce dissolved oxygen levels by impeding smooth current flow. To address this issue, research has been conducted to replace conventional synthetic fiber cage nets with brass nets, demonstrating certain benefits such as improved productivity and ease of fish cage management. However, given the need for a more thorough examination of brass fishing net weaving technology and performance, this study assessed the optimal weaving method for brass fishing nets to be used in fish cages. Additionally, it provided essential data for the practical application of brass fishing nets by evaluating their weight, tensile strength, elongation, fatigue resistance, and wear resistance. The study concluded that weaving brass fishing nets using the chain link method ensures durability, ease of installation, and compact storage in a scroll-like form. Moreover, due to their superior fatigue and wear resistance properties, brass nets can offer increased utility if appropriate net diameter and length are selected to compensate for their higher weight per unit area and relatively higher cost compared to existing fiber fishing nets.