1.Study on synthesis of some compounds of azometine base, derivatives of vanilline and exploration of its biological effects
Pharmaceutical Journal 1999;274(2):9-10
Synthesis research and test on biological activities of some azomethines from vanilline and 5-Nitro vanilline. 10 azomethines can be obtained by condensing vanilline and 5-Nitro Vanilline with aromatic amines such as aniline, pAB, p.Bromoe aniline, or.Toluidin, anthraniclic acid. The structures of obtained products have been characterized by element analyses and IR, UV spectroscopy. The compounds have been tested for antibacterial activities on positive gram bacteria rather than on negative ones. Azomethines of 5-Nitro vanillin have great effect in antibacterial and antifungal activities.
Pharmaceutical Preparations
;
Relative Biological Effectiveness
2.Study on the synthesis and bioactivities of beta-aminoceton derivatives of 5 bromo-vanilin
Pharmaceutical Journal 1999;274(2):10-12
By the condensation of azometines, 5-bromovalline with azomatic ketones, six beta-aminoketones was formed. All compounds was tested on 10 strains of bacteria and candida albicans in vitro. The results showed that synthesized compounds had strong antibacterial and antifungal activities.
Pharmaceutical Preparations
;
Relative Biological Effectiveness
3.Dosimetric Characteristics of a Thermal Neutron Beam Facility for Neutron Capture Therapy at HANARO Reactor.
Dong Han LEE ; Mi Sook KIM ; Soheigh SUH ; Young Hoon JI ; Moon Sik CHOI ; Jae Hong PARK ; Kum Bae KIM ; Seung Yul YOO ; Myong Seop KIM ; Byung Chul LEE ; Ki Jung CHUN ; Jae Won CHO
Korean Journal of Medical Physics 2007;18(2):87-92
A thermal neutron beam facility utilizing a typical tangential beam port for Neutron Capture Therapy was installed at the HANARO, 30 MW multi-purpose research reactor. Mixed beams with different physical characteristics and relative biological effectiveness would be emitted from the BNCT irradiation facility, so a quantitative analysis of each component of the mixed beams should be performed to determine the accurate delivered dose. Thus, various techniques were applied including the use of activation foils, TLDs and ionization chambers. All the dose measurements were performed with the water phantom filled with distilled water. The results of the measurement were compared with MCNP4B calculation. The thermal neutron fluxes were 1.02E9 n/cm2 s and 6.07E8 n/cm2 s at 10 and 20 mm depth respectively, and the fast neutron dose rate was insignificant as 0.11 Gy/hr at 10 mm depth in water. The gamma-ray dose rate was 5.10 Gy/hr at 20 mm depth in water. Good agreement within 5%, has been obtained between the measured dose and the calculated dose using MCNP for neutron and gamma component and discrepancy with 14% for fast neutron flux. Considering the difficulty of neutron detection, the current study support the reliability of these results and confirmed the suitability of the thermal neutron beam as a dosimetric data for BNCT clinical trials.
Fast Neutrons
;
Neutron Capture Therapy*
;
Neutrons*
;
Relative Biological Effectiveness
;
Water
4.Frequency of Micronuclei in Lymphocytes Following Gamma and Fast-neutron Irradiations.
Sung Ho KIM ; Chul Koo CHO ; Tae Hwan KIM ; In Yong CHUNG ; Seong Yul YOO ; Kyoung Hwan KOH ; Hyong Geun YUN
Journal of the Korean Society for Therapeutic Radiology 1993;11(1):35-42
The dose response of the number of micronuclei in cytokinesis-blocked (CB) lymphocytes after in vitro irradiation with -rays and neutrons in the 5 dose ranges was studied for a heterogeneous population of 4 donors. One thousand binucleated cells were systematically scored for micronuclei. Measurements performed after irradiation showed a dose-dependent increase in micronuclei(MN) frequency in each of the doctors studied. The dose-response curves were analyzed by a linear-quadratic model, frequencies per 1000 CB cells were (0.31+/-0.049) D+(0.0022+/-0.0002) D2+(13.19+/-1.854) (r2=1.000, X2=0.7074, p=0.95) following irradiation, and (0.99+/-0.528) D+(0.0093+/-0.0047) D2+(13.31+/-7.309) (r2=0.996, X2=7.6834, p=0.11) following neutrons irradiation (D is irradiation dose in cGy). The relative biological effectiveness (RBE) of neutrons compared with -rays was estimated by best fitting linear-quadratic model. In the micronuclei frequency between 0.05 and 0.8 per cell, the RBE of neutrons was 2.37+/-0.17. Since the MN assay is simple and rapid, it may be a good tool for evaluating the y-ray and neutron response.
Humans
;
Lymphocytes*
;
Neutrons
;
Relative Biological Effectiveness
;
Tissue Donors
5.Basics of particle therapy II: relative biological effectiveness.
Radiation Oncology Journal 2012;30(1):1-13
In the previous review, the physical aspect of heavy particles, with a focus on the carbon beam was introduced. Particle beam therapy has many potential advantages for cancer treatment without increasing severe side effects in normal tissue, these kinds of radiation have different biologic characteristics and have advantages over using conventional photon beam radiation during treatment. The relative biological effectiveness (RBE) is used for many biological, clinical endpoints among different radiation types and is the only convenient way to transfer the clinical experience in radiotherapy with photons to another type of radiation therapy. However, the RBE varies dependent on the energy of the beam, the fractionation, cell types, oxygenation status, and the biological endpoint studied. Thus this review describes the concerns about RBE related to particle beam to increase interests of the Korean radiation oncologists' society.
Carbon
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Cell Fractionation
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Oxygen
;
Photons
;
Population Characteristics
;
Protons
;
Relative Biological Effectiveness
6.Neutron therapy for prostatic cancer.
Yong Soo LIM ; Myung Soo LIM ; Ho Kun MOON ; Kang Hyun LEE ; Hi Joong AHN ; Seong Yul YOO
Korean Journal of Urology 1992;33(6):979-984
The neutron beam has higher relative biological effectiveness (RBE) than conventional X or gamma ray because it is densely ionizing radiation which is presented by high linear energy transfer (LET). This physical and radiobiological characteristic plays an important role in killing of cancer cells in the state of biologically radio-resistant to the conventional radiation. The rationale of high LET radiation in the application to clinical radiotherapy is summarized as, high oxygen enhancement ratio (OER), less repair of cell damage, and less dependence of radio-sensitivity on cell cycle. Neutron therapy alone or combined with conventional radiotherapy was performed in 12 patients with stage C or D1 prostatic cancer from Mar. 1987 to Dec. 1989 in Korea Cancer Center Hospital. Local control rate at the time of 24 months after therapy was 67% (4/6) in stage C and 67% (4/6) in stage DI. Two-year actuarial survival rate after therapy was 82% in stage C and 67% in stage D1. The problem of neutron therapy was relatively high incidence of major complication rate, but it could be lessened by the accumulation of experience for neutron therapy. We think neutron therapy to be one of adequate treatment modalities for local control of stage C or Dl prostatic cancer.
Cell Cycle
;
Gamma Rays
;
Homicide
;
Humans
;
Incidence
;
Korea
;
Linear Energy Transfer
;
Neutrons*
;
Oxygen
;
Prostatic Neoplasms*
;
Radiation, Ionizing
;
Radiotherapy
;
Relative Biological Effectiveness
;
Survival Rate
7.Multi-institutional Comparison of Intensity Modulated Radiation Therapy (IMRT) Planning Strategies and Planning Results for Nasopharyngeal Cancer.
Sung Ho PARK ; Hee Chul PARK ; Suk Won PARK ; Do Hoon OH ; Youngmin CHOI ; Jeung Kee KIM ; Yong Chan AHN ; Won PARK ; Hyun Sook SUH ; Rena LEE ; Hoonsik BAE
Journal of Korean Medical Science 2009;24(2):248-255
The intensity-modulated radiation therapy (IMRT) planning strategies for nasopharyngeal cancer among Korean radiation oncology facilities were investigated. Five institutions with IMRT planning capacity using the same planning system were invited to participate in this study. The institutions were requested to produce the best plan possible for 2 cases that would deliver 70 Gy to the planning target volume of gross tumor (PTV1), 59.4 Gy to the PTV2, and 51.5 Gy to the PTV3 in which elective irradiation was required. The advised fractionation number was 33. The planning parameters, resultant dose distributions, and biological indices were compared. We found 2-3-fold variations in the volume of treatment targets. Similar degree of variation was found in the delineation of normal tissue. The physician-related factors in IMRT planning had more influence on the plan quality. The inhomogeneity index of PTV dose ranged from 4 to 49% in Case 1, and from 5 to 46% in Case 2. Variation in tumor control probabilities for the primary lesion and involved LNs was less marked. Normal tissue complication probabilities for parotid glands and skin showed marked variation. Results from this study suggest that greater efforts in providing training and continuing education in terms of IMRT planning parameters usually set by physician are necessary for the successful implementation of IMRT.
Female
;
Humans
;
Male
;
Middle Aged
;
Nasopharyngeal Neoplasms/*radiotherapy
;
Parotid Gland/radiation effects
;
Radiotherapy Dosage
;
Radiotherapy Planning, Computer-Assisted/*methods
;
Radiotherapy, Intensity-Modulated/*methods
;
Relative Biological Effectiveness
;
Skin/radiation effects
;
Tumor Burden
;
Young Adult
8.Static magnetic fields promote osteoblastic/cementoblastic differentiation in osteoblasts, cementoblasts, and periodontal ligament cells.
Eun Cheol KIM ; Jaesuh PARK ; Il Keun KWON ; Suk Won LEE ; Su Jung PARK ; Su Jin AHN
Journal of Periodontal & Implant Science 2017;47(5):273-291
PURPOSE: Although static magnetic fields (SMFs) have been used in dental prostheses and osseointegrated implants, their biological effects on osteoblastic and cementoblastic differentiation in cells involved in periodontal regeneration remain unknown. This study was undertaken to investigate the effects of SMFs (15 mT) on the osteoblastic and cementoblastic differentiation of human osteoblasts, periodontal ligament cells (PDLCs), and cementoblasts, and to explore the possible mechanisms underlying these effects. METHODS: Differentiation was evaluated by measuring alkaline phosphatase (ALP) activity, mineralized nodule formation based on Alizarin red staining, calcium content, and the expression of marker mRNAs assessed by reverse transcription polymerase chain reaction (RT-PCR). Signaling pathways were analyzed by western blotting and immunocytochemistry. RESULTS: The activities of the early marker ALP and the late markers matrix mineralization and calcium content, as well as osteoblast- and cementoblast-specific gene expression in osteoblasts, PDLCs, and cementoblasts were enhanced. SMFs upregulated the expression of Wnt proteins, and increased the phosphorylation of glycogen synthase kinase-3β (GSK-3β) and total β-catenin protein expression. Furthermore, p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK), and nuclear factor-κB (NF-κB) pathways were activated. CONCLUSIONS: SMF treatment enhanced osteoblastic and/or cementoblastic differentiation in osteoblasts, cementoblasts, and PDLCs. These findings provide a molecular basis for the beneficial osteogenic and/or cementogenic effect of SMFs, which could have potential in stimulating bone or cementum formation during bone regeneration and in patients with periodontal disease.
Alkaline Phosphatase
;
Blotting, Western
;
Bone Regeneration
;
Calcium
;
Dental Cementum*
;
Dental Prosthesis
;
Gene Expression
;
Glycogen Synthase
;
Guided Tissue Regeneration, Periodontal
;
Humans
;
Immunohistochemistry
;
JNK Mitogen-Activated Protein Kinases
;
Magnetic Fields*
;
Miners
;
Osteoblasts*
;
Periodontal Diseases
;
Periodontal Ligament*
;
Phosphorylation
;
Polymerase Chain Reaction
;
Protein Kinases
;
Regeneration
;
Relative Biological Effectiveness
;
Reverse Transcription
;
RNA, Messenger
;
Signal Transduction
;
Wnt Proteins