• Title/Summary/Keyword: Biomedical

Search Result 13,383, Processing Time 0.04 seconds

Bladder And Rectum Dose Define 3D Treatment Planning for Cervix Cancer Brachtherapy Comparison of Dose-Volume Histograms for Organ Contour and Organ Wall Contour (자궁경부암의 고선량률 근접치료시 장기묘사 방법에 따른 직장과 방광의 선량비교 분석)

  • Kim, Jong-Won;Kim, Dae-Hyun;Choi, Joon-Yong;Won, Yeong-Jin
    • Journal of radiological science and technology
    • /
    • v.35 no.4
    • /
    • pp.327-333
    • /
    • 2012
  • Purpose: To analyze the correlation between dose volume histograms(DVH) based on organ outer wall contour and organ wall delineation for bladder and rectum, and to compare the doses to these organs with the absorbed doses at the bladder and rectum. Material and methods: Individual CT based brachytherapy treatment planning was performed in 13 patients with cervical cancer as part of a prospective comparative trial. The external contours and the organ walls were delineated for the bladder and rectum in order to compute the corresponding dose volume histograms. The minimum dose in 0.1 $cm^3$, 1 $cm^3$, 2 $cm^3$, 5 $cm^3$, 10 $cm^3$ volumes receiving the highest dose were compared with the absorbed dose at the rectum and bladder reference point. Results: The bladder and rectal doses derived from organ outer wall contour and computed for volumes of 2 $cm^3$, provided a good estimate for the doses computed for the organ wall contour only. This correspondence was no longer true when large volumes were considered. Conclusion: For clinical applications, when volumes smaller than 5 $cm^2$ are considered, the dose-volume histograms computed from external organ contours for the bladder and rectum can be used instead of dose -volume histograms computed for the organ walls only. External organ contours are indeed easier to obtain. The dose at the ICRU rectum reference point provides a good estimate of the rectal dose computed for volumes smaller than 2 $cm^2$ only for a midline position of the rectum. The ICRU bladder reference point provides a good estimate of the dose computed for the bladder wall only in cases of appropriate balloon position.

Application of the Pulsatile Cardiopulmonary Bypass in Animal Model (이중 박동성 인공심폐기의 동물 실험)

  • Shin, Hwa-Kyun;Won, Yong-Soon;Lee, Jea-Yook;Her, Keun;Yeum, Yook;Kim, Seung-Chul;Min, Byoung-Goo
    • Journal of Chest Surgery
    • /
    • v.37 no.1
    • /
    • pp.1-10
    • /
    • 2004
  • Background: Currently, the cardiopulmonary machine with non-pulsatile pumps, which are low in internal circuit pressure and cause little damage to blood cells, is widely used. However, a great number of experimental studies shows that pulsatile perfusions are more useful than non-pulsatile counterparts in many areas, such as homodynamic, metabolism, organ functions, and micro-circulation. Yet, many concerns relating to pulsatile cardiopulmonary machines, such as high internal circuit pressure and blood cell damage, have long hindered the development of pulsatile cardiopulmonary machines. Against this backdrop, this study focuses on the safety and effectiveness of the pulsatile cardiopulmonary machines developed by a domestic research lab. Material and Method: The dual-pulsatile cardiopulmonary bypass experiment with total extracorporeal circulation was conducted on six calves, Extracorporeal circulation was provided between superior/inferior vena cava and aorta. The membrane oxygenator, which was placed between the left and right pumps, was used for blood oxygenation. Circulation took four hours. Arterial blood gas analysis and blood tests were also conducted. Plasma hemoglobin levels were calculated, while pulse pressure and internal circuit pressure were carefully observed. Measurement was taken five times; once before the operation of the cardiopulmonary bypass, and after its operation it was taken every hour for four hours. Result: Through the arterial blood gas analysis, PCO2 and pH remained within normal levels. PO2 in arterial blood showed enough oxygenation of over 100 mmHg. The level of plasma hemoglobin, which had total cardiopulmonary circulation, steadily increased to 15.87 $\pm$ 5.63 after four hours passed, but remained below 20 mg/㎗. There was no obvious abnormal findings in blood test. Systolic blood pressure which was at 97.5$\pm$5.7 mmHg during the pre-circulation contraction period, was maintained over 100 mmHg as time passed. Moreover, diastolic blood pressure was 72.2 $\pm$ 7.7 mmHg during the expansion period and well kept at the appropriate level with time passing by. Average blood pressure which was 83$\pm$9.2 mmHg before circulation, increased as time passed, while pump flow was maintained over 3.3 L/min. Blood pressure fluctuation during total extracorporeal circulation showed a similar level of arterial blood pressure of pre-circulation heart. Conclusion: In the experiment mentioned above, pulsatile cardiopulmonary machines using the doual-pulsatile structure provided effective pulsatile blood flow with little damage in blood cells, showing excellence in the aspects of hematology and hemodynamic. Therefore, it is expected that the pulsatile cardiopulmonary machine, if it becomes a standard cardiopulmonary machine in all heart operations, will provide stable blood flow to end-organs.

Evaluation of Glioma with Thallium-201 Brain SPECT: The Correlation with $^1H$ MR Spectroscopy and Pathology ($^{201}Tl$ 뇌 SPECT을 이용한 신경교종의 평가)

  • Sohn, Hyung-Sun;Kim, Euy-Neyng;Kim, Sung-Hoon;Yoo, Ie-Ryung;Chung, Yong-An;Chung, Soo-Kyo;Hong, Yong-Gil;Lee, Youn-Soo;Choe, Bo-Young
    • The Korean Journal of Nuclear Medicine
    • /
    • v.34 no.6
    • /
    • pp.465-477
    • /
    • 2000
  • Purpose: Thallim-201 ($^{201}Tl$) brain SPECT and proton ($^1H$) magnetic resonance spectroscopy (MRS) have been used to evaluate tumor grade and viability of glioma. We assessed the correlations between $^{201}Tl$ brain index or spectrum of metabolites of $^1H$ MRS and grade of glioma or histopathologic findings. Materials and Methods: We studied 17 patients (4 astrocytoma, 7 anaplastic astrocytoma and 6 glioblastoma). On $^{201}Tl$ Brain SPECT, $^{201}Tl$ index was measured as the ratio of average counts for region of interest to those for the contralateral normal brain. On $^1H$ MRS, we calculated choline (Cho) /creatine (Cr) ratio and N-acetylaspartate (NAA)/Cr ratio in ROI defined as tumor center. Histopathologic findings were graded by Ki-67 index, cellularity, mitosis, pleomorphism, necrosis and endothelial proliferation. An unpaired t test and statistical correlations were performed to evaluate these data. Results: Tl-index showed the best correlation with Ki-67 index (p<0.01), less correlations with cellularity, mitosis, and endothelial proliferation, but no correlation with results of MRS, pleomorphism, or necrosis. The findings of MRS did not correlate with all of the above. The cases of glioblastoma demonstrated a higher Tl-index, Cho/cr ratio, Ki-67 index and lower NAA/Cr ratio, albeit without statistical significance. Conclusion: Even though $^{201}Tl$ brain SPECT did not correlate directly with grade of malignancy, it may still be useful in determining biological aggressiveness of tumor and prognosis of patients because it correlated well with Ki-67 index, a growth fraction of glioma, cellularity, mitosis and endothelial proliferation.

  • PDF

Functional Brain Mapping Using $H_2^{15}O$ Positron Emission Tomography ( II ): Mapping of Human Working Memory ($H_2^{15}O$ 양전자단층촬영술을 이용한 뇌기능 지도 작성(II): 작업 기억의 지도 작성)

  • Lee, Jae-Sung;Lee, Dong-Soo;Lee, Sang-Kun;Nam, Hyun-Woo;Kim, Seok-Ki;Park, Kwang-Suk;Jeong, Jae-Min;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
    • /
    • v.32 no.3
    • /
    • pp.238-249
    • /
    • 1998
  • Purpose: To localize and compare the neural basis of verbal and visual human working memory, we performed functional activation study using $H_2^{15}O$ PET. Materials and Methods: Repeated $H_2^{15}O$ PET scans with one control and three different activation tasks were performed on six right-handed normal volunteers. Each activation task was composed of 13 match-ing trials. On each trial, four targets, a fixation dot and a probe were presented sequentially and subject's task was to press a response button to indicate whether or not the probe was one of the previous targets. Short meaningful Korean words, simple drawings and monochromic pictures of human faces were used as matching objects for verbal or visual memory. All the images were spatially normalized and the differences between control and activation states were statistically analyzed using SPM96. Results: Statistical analysis of verbal memory activation with short words showed activation in the left Broca's area, promoter cortex, cerebellum and right cingulate gyrus. In verbal memory with simple drawings, activation was shown in the larger regions including where activated with short words and left superior temporal cortex, basal ganglia, thalamus, prefrontal cortex, anterior portion of right superior temporal gyrus and right infero-lateral frontal cortex. On the other hand, the visual memory task activated predominantly right-sided structures, especially inferior frontal cortex, supplementary motor cortex and superior parietal cortex. Conclusion: The results are consistent with the hypothesis of the laterality and dissociation of the verbal and visual working memory from the invasive electrophysiological studies and emphasize the pivotal role of frontal cortex and cingulate gyrus in working memory system.

  • PDF

Facile Fabrication of Animal-Specific Positioning Molds For Multi-modality Molecular Imaging (다중 분자 영상을 위한 간편한 동물 특이적 자세 고정틀의 제작)

  • Park, Jeong-Chan;Oh, Ji-Eun;Woo, Seung-Tae;Kwak, Won-Jung;Lee, Jeong-Eun;Kim, Kyeong-Min;An, Gwang-Il;Choi, Tae-Hyun;Cheon, Gi-Jeong;Chang, Young-Min;Lee, Sang-Woo;Ahn, Byeong-Cheol;Lee, Jae-Tae;Yoo, Jeong-Soo
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.42 no.5
    • /
    • pp.401-409
    • /
    • 2008
  • Purpose: Recently multi-modal imaging system has become widely adopted in molecular imaging. We tried to fabricate animal-specific positioning molds for PET/MR fusion imaging using easily available molding clay and rapid foam. The animal-specific positioning molds provide immobilization and reproducible positioning of small animal. Herein, we have compared fiber-based molding clay with rapid foam in fabricating the molds of experimental animal. Materials and Methods: The round bottomed-acrylic frame, which fitted into microPET gantry, was prepared at first. The experimental mice was anesthetized and placed on the mold for positioning. Rapid foam and fiber-based clay were used to fabricate the mold. In case of both rapid foam and the clay, the experimental animal needs to be pushed down smoothly into the mold for positioning. However, after the mouse was removed, the fabricated clay needed to be dried completely at $60^{\circ}C$ in oven overnight for hardening. Four sealed pipet tips containing $[^{18}F]FDG$ solution were used as fiduciary markers. After injection of $[^{18}F]FDG$ via tail vein, microPET scanning was performed. Successively, MRI scanning was followed in the same animal. Results: Animal-specific positioning molds were fabricated using rapid foam and fiber-based molding clay for multimodality imaging. Functional and anatomical images were obtained with microPET and MRI, respectively. The fused PET/MR images were obtained using freely available AMIDE program. Conclusion: Animal-specific molds were successfully prepared using easily available rapid foam, molding clay and disposable pipet tips. Thanks to animal-specific molds, fusion images of PET and MR were co-registered with negligible misalignment.

Extracts of Allium fistulosum Attenuates Pro-Inflammatory Action in the Lipopolysaccharide-Stimulated BV2 Microglia Cells (Lipopolysaccharide에 의한 BV2 세포의 염증 반응에 대한 파 추출물의 저해 활성)

  • Park, Shin-Hyoung;Kim, Jung-In;Jeong, Yong-Kee;Choi, Yung-Hyun
    • Journal of Life Science
    • /
    • v.21 no.6
    • /
    • pp.796-804
    • /
    • 2011
  • Microglia are central nervous system (CNS)-resident professional macrophages that function as the principal immune cells responding to pathological stimulations in the CNS. Activation of microglia, induced by various pathogens, protects neurons and maintains homeostasis in the CNS, but severe activation causes inflammatory responses secreting various neurotoxic molecules such as nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$) and pro-inflammatory cytokines. Allium fistulosum, a member of the onion family, is mainly cultivated for consumption, as well as medicinal use in Oriental medicine. It has been reported that A. fistulosum has various biological effects such as anti-oxidant, anti-platelet aggregation, anti-fungus and anti-cholesterol synthesis, however there has been no research about the anti-inflammatory effects of A. fistulosum extracts. In this study, it was undertaken to explore the functions of A. fistulosum as a suppressor of neuronal inflammation by using BV2 microglia cells. As a result, it was found that four kinds of extracts of A. fistulosum effectively reduced the expressions of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) at both mRNA and protein levels, and also attenuated pro-inflammatory cytokines such as tumor necrosis alpha (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$) and interleukin-6 (IL-6) at the mRNA level in BV2 stimulated by lipopolysaccharide (LPS). In addition, the extracts of A. fistulosum attenuated the release of NO markedly, as well as resulting in slight decreases of TNF-${\alpha}$ and IL-6 production, the effects of which were most significant when treated with ethyl alcohol extract from the whole A. fistulosum. In conclusion, the data indicated that the anti-inflammatory actions of A. fistulosum against BV2 microglia cells is through the down-regulation of iNOS, COX2 and pro-inflammatory cytokines such as TNF-${\alpha}$ and IL-6, and these effects are expected to help in the protection of nerve tissues by suppressions of neuronal inflammation in various neurodegenerative diseases.

Epidemiologic Study of Zoophilic Dermatophytoses between 2010 and 2016 (2010~2016년 동안 동물친화성 피부 사상균 감염의 역학적 연구)

  • Kim, Su Jung
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.49 no.4
    • /
    • pp.439-445
    • /
    • 2017
  • In recent years, change in life patterns gave rise to an increase in the number of families with companion animals, and as a result, frequent dermatophytes infections have been reported. Microsporum canis, Trichophyton mentagrophytes, and Trichophyton verrucosum, are among these species of zoophilic dermatophytes. Trichophyton mentagrophytes are transmitted to humans by contact with wild animals. Infection from it causes strong inflammation in humans. Conversely, Trichophyton verrucosum is transmitted by contact with cattles. Microsporum canis will become latent carriers in cats or dogs, causing infectious diseases when it comes in contact with humans. We investigated zoophilic dermatophytes isolated according to annual, sex, age, season, body sites, and clinical types between 2010 and 2016. According to our results, the isolation rate of zoophilic dermatophytes was 0.37%, among which, 88 T. mentagrophytes, 228 Microsporum canis, and 18 Trichophyton verrucosum were isolated in human. It is interesting to note that Microsporum canis has been on the rise since 2014. Microsporum canis and Trichophyton verrucosum were highly isolated in females, but T. mentagrophytes was isolated similarly in both sexes. According to an age-based survey, the isolation rate was higher in children younger than 10 years. Our results is a valuable data for predicting and studying the isolation of zoophilic dermatophytes in the future.

Competitive ELISA for the Measurement of Glycoprotein Purified from Acanthopanx senticosus (가시오가피로부터 분리한 단백 다당물질의 경쟁적 ELISA법에 의한 분석)

  • Ha, Eun-Suk;Hwang, Soo-Hyun;Shin, Kwang-Soon;Yu, Kwang-Won;Lee, Keyung-Ho;Choi, Joo-Sun;Park, Woo-Mun;Yoon, Taek-Joon
    • Korean Journal of Food Science and Technology
    • /
    • v.35 no.6
    • /
    • pp.1209-1215
    • /
    • 2003
  • This study was carried out to establish a quantitative analysis method of separating immuno-activating substance (EN-SP) from Acanthopanax senticosus (A. senticosus) by competitive direct ELISA. Mouse antiserum (anti-EN-SP) against EN-SP was generated by immunization (s.c.) of EN-SP purified from A. senticosus as an immunogen. The titer of anti-EN-SP was about 1 : 400, and the optimal dilution of EN-SP-HRP conjugate was 1 : 1,000. When the standard curve was constructed by ELISA, its sensitivity was about $0.2{\mu}g/mL$. The coefficient variation of intra- and inter-assay were $6.13{\sim}8.81%$ and $6.73{\sim}8.60%$, respectively. According to the standard curve, the concentration of EN-SP in various senticosus extracts was found to be only $59.85\;{\mu}g$ in 10mg of extract from the bark of A. senticosus. Similarly, the immunostimulating activity to produce $TNF-{\alpha}$ or IL-12 among the various extracts of Acanthopanax was shown to be correlated with the content of EN-SP. These results demonstrated that competitive ELISA was a convenient, fast, reproducible, and accurate method for the determination of EN-SP as an immunologically active standard substance in extract of A. senticosus.

Egg Antibody Farming and IgY Technology for Food and Biomedical Applications (식품과 생의학을 위한 계란 항체생산과 IgY 기술의 활용)

  • Sim, Jeong S.;Sunwoo, Hoon H.
    • Proceedings of the Korea Society of Poultry Science Conference
    • /
    • 2003.07b
    • /
    • pp.37-54
    • /
    • 2003
  • It has been recognized that the hen. like its mammalian counterparts. provides young chicks with antibodies as protection against hostile invaders. This system facilitates the transfer of specific antibodies from serum to egg yolk. and provides a supply of antibodies called immunoglobulin Y(IgY) to the developing embryo and the hatched chick. The protection against pathogens that the relatively immuno-incompetent newly hatched chick has. is through transmission of antibodies from the mother via the egg. Egg yolk. therefore. can be loaded with a large amount of IgY against pathogens which can immobilize the existing or invading pathogens during the embryo development or in day-old chicks. Thus. the immunization of laying hens to various pathogens results in production of different antigen-specific IgY in eggs. Egg yolk contains 8~20 mg of immunoglobulins (IgY) per $m\ell$ or 136~340 mg per yolk suggesting that more than 30 g of IgY can be obtained from one immunized hen in a year. By immunizing laying hens with antigens and collecting IgY from egg yolk. low cost antibodies at less than $10 per g compared to more than $20.000 per g of mammalian IgG can be obtained. This IgY technology opens new potential market applications in medicine. public health veterinary medicine and food safety. A broader use of IgY technology could be applied as biological or diagnostic tool. nut-raceutical or functional food development. oral-supplementation for prophylaxis. and as pathogen-specific antimicrobial agents for infectious disease control. This paper has emphasized that when IgY-loaded chicken eggs are produced and consumed. the specific antibody binds. immobilizes and consequently reduces or inhibits the growth or colony forming abilities of microbial pathogens. This concept could serve as an alternative agent to replace the use of antibiotics. since today. more and more antibiotics are less effective in the treatment of infections. due to the emergence of drug-resistant bacteria.

  • PDF

Development of a Dose Calibration Program for Various Dosimetry Protocols in High Energy Photon Beams (고 에너지 광자선의 표준측정법에 대한 선량 교정 프로그램 개발)

  • Shin Dong Oh;Park Sung Yong;Ji Young Hoon;Lee Chang Geon;Suh Tae Suk;Kwon Soo IL;Ahn Hee Kyung;Kang Jin Oh;Hong Seong Eon
    • Radiation Oncology Journal
    • /
    • v.20 no.4
    • /
    • pp.381-390
    • /
    • 2002
  • Purpose : To develop a dose calibration program for the IAEA TRS-277 and AAPM TG-21, based on the air kerma calibration factor (or the cavity-gas calibration factor), as well as for the IAEA TRS-398 and the AAPM TG-51, based on the absorbed dose to water calibration factor, so as to avoid the unwanted error associated with these calculation procedures. Materials and Methods : Currently, the most widely used dosimetry Protocols of high energy photon beams are the air kerma calibration factor based on the IAEA TRS-277 and the AAPM TG-21. However, this has somewhat complex formalism and limitations for the improvement of the accuracy due to uncertainties of the physical quantities. Recently, the IAEA and the AAPM published the absorbed dose to water calibration factor based, on the IAEA TRS-398 and the AAPM TG-51. The formalism and physical parameters were strictly applied to these four dose calibration programs. The tables and graphs of physical data and the information for ion chambers were numericalized for their incorporation into a database. These programs were developed user to be friendly, with the Visual $C^{++}$ language for their ease of use in a Windows environment according to the recommendation of each protocols. Results : The dose calibration programs for the high energy photon beams, developed for the four protocols, allow the input of informations about a dosimetry system, the characteristics of the beam quality, the measurement conditions and dosimetry results, to enable the minimization of any inter-user variations and errors, during the calculation procedure. Also, it was possible to compare the absorbed dose to water data of the four different protocols at a single reference points. Conclusion : Since this program expressed information in numerical and data-based forms for the physical parameter tables, graphs and of the ion chambers, the error associated with the procedures and different user could be solved. It was possible to analyze and compare the major difference for each dosimetry protocol, since the program was designed to be user friendly and to accurately calculate the correction factors and absorbed dose. It is expected that accurate dose calculations in high energy photon beams can be made by the users for selecting and performing the appropriate dosimetry protocol.