• Title/Summary/Keyword: Tissues distribution

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Dosimetric Validation of the Acuros XB Advanced Dose Calculation Algorithm for Volumetric Modulated Arc Therapy Plans

  • Park, So-Yeon;Park, Jong Min;Choi, Chang Heon;Chun, Minsoo;Kim, Jung-in
    • Progress in Medical Physics
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    • v.27 no.4
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    • pp.180-188
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    • 2016
  • Acuros XB advanced dose calculation algorithm (AXB, Varian Medical Systems, Palo Alto, CA) has been released recently and provided the advantages of speed and accuracy for dose calculation. For clinical use, it is important to investigate the dosimetric performance of AXB compared to the calculation algorithm of the previous version, Anisotropic Analytical Algorithm (AAA, Varian Medical Systems, Palo Alto, CA). Ten volumetric modulated arc therapy (VMAT) plans for each of the following cases were included: head and neck (H&N), prostate, spine, and lung. The spine and lung cases were treated with stereotactic body radiation therapy (SBRT) technique. For all cases, the dose distributions were calculated using AAA and two dose reporting modes in AXB (dose-to-water, $AXB_w$, and dose-to-medium, $AXB_m$) with same plan parameters. For dosimetric evaluation, the dose-volumetric parameters were calculated for each planning target volume (PTV) and interested normal organs. The differences between AAA and AXB were statistically calculated with paired t-test. As a general trend, $AXB_w$ and $AXB_m$ showed dose underestimation as compared with AAA, which did not exceed within -3.5% and -4.5%, respectively. The maximum dose of PTV calculated by $AXB_w$ and $AXB_m$ was tended to be overestimated with the relative dose difference ranged from 1.6% to 4.6% for all cases. The absolute mean values of the relative dose differences were $1.1{\pm}1.2%$ and $2.0{\pm}1.2%$ when comparing between AAA and $AXB_w$, and AAA and $AXB_m$, respectively. For almost dose-volumetric parameters of PTV, the relative dose differences are statistically significant while there are no statistical significance for normal tissues. Both $AXB_w$ and $AXB_m$ was tended to underestimate dose for PTV and normal tissues compared to AAA. For analyzing two dose reporting modes in AXB, the dose distribution calculated by $AXB_w$ was similar to those of AAA when comparing the dose distributions between AAA and $AXB_m$.

Extraction of Muscle Areas from Ultrasonographic Images using Information of Fascia (근막 정보를 이용한 초음파 영상에서의 근육 영역 추출)

  • Kim, Kwang-Baek
    • Journal of Korea Multimedia Society
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    • v.11 no.9
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    • pp.1296-1301
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    • 2008
  • Ultrasonography constructs pictures of areas inside the body needs in diagnosis by bouncing high-enorgy sound waves(ultrasound) off internal tissues or organs. In constructing an ultrasonographic image, the weakness of bounding signals induces noises and detailed differences of brightness, so that having a difficulty in detecting and diagnosing with the naked eyes in the analysis of ultrasonogram. Especially, the difficulty is extended when diagnosing muscle areas by using ultrasonographic images in the musculoskeletal test. In this paper, we propose a novel image processing method that computationally extracts a muscle area from an ultrasonographic image to assist in diagnosis. An ultrasonographic image consists of areas corresponding to various tissues and internal organs. The proposed method, based on features of intensity distribution, morphology and size of each area, extracts areas of the fascia, the subcutaneous fat and other internal organs, and then extracts a muscle area enclosed by areas of the fascia. In the extraction of areas of the fascia, a series of image processing methods such as histogram stretching, multiple operation, binarization and area connection by labeling is applied. A muscle area is extracted by using features on relative position and morphology of areas for the fascia and muscle areas. The performance evaluation using real ultrasonographic images and specialists' analysis show that the proposed method is able to extract target areas being approximate to real muscle areas.

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Twenty-Eight-Day Repeated Inhalation Toxicity Study of Nano-Sized Neodymium Oxide in Male Sprague-Dawley Rats

  • Kim, Yong-Soon;Lim, Cheol-Hong;Shin, Seo-Ho;Kim, Jong-Choon
    • Toxicological Research
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    • v.33 no.3
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    • pp.239-253
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    • 2017
  • Neodymium is a future-oriented material due to its unique properties, and its use is increasing in various industrial fields worldwide. However, the toxicity caused by repeated exposure to this metal has not been studied in detail thus far. The present study was carried out to investigate the potential inhalation toxicity of nano-sized neodymium oxide ($Nd_2O_3$) following a 28-day repeated inhalation exposure in male Sprague-Dawley rats. Male rats were exposed to nano-sized $Nd_2O_3-containing$ aerosols via a nose-only inhalation system at doses of $0mg/m^3$, $0.5mg/m^3$, $2.5mg/m^3$, and $10mg/m^3$ for 6 hr/day, 5 days/week over a 28-day period, followed by a 28-day recovery period. During the experimental period, clinical signs, body weight, hematologic parameters, serum biochemical parameters, necropsy findings, organ weight, and histopathological findings were examined; neodymium distribution in the major organs and blood, bronchoalveolar lavage fluid (BALF), and oxidative stress in lung tissues were analyzed. Most of the neodymium was found to be deposited in lung tissues, showing a dose-dependent relationship. Infiltration of inflammatory cells and pulmonary alveolar proteinosis (PAP) were the main observations of lung histopathology. Infiltration of inflammatory cells was observed in the $2.5mg/m^3$ and higher dose treatment groups. PAP was observed in all treatment groups accompanied by an increase in lung weight, but was observed to a lesser extent in the $0.5mg/m^3$ treatment group. In BALF analysis, total cell counts, including macrophages and neutrophils, lactate dehydrogenase, albumin, interleukin-6, and tumor necrosis factor-alpha, increased significantly in all treatment groups. After a 4-week recovery period, these changes were generally reversed in the $0.5mg/m^3$ group, but were exacerbated in the $10mg/m^3$ group. The lowest-observed-adverse-effect concentration of nano-sized $Nd_2O_3$ was determined to be $0.5mg/m^3$, and the target organ was determined to be the lung, under the present experimental conditions in male rats.

Distribution and Role of Mitochondrial Lactate Dehydrogenase Isozymes in Bird and Mammals (조류 및 포유류 내 미토콘드리아 젖산탈수소효소 동위효소들의 분포와 역할)

  • Cho, Sung Kyu;Yum, Jung Joo
    • Journal of Life Science
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    • v.27 no.5
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    • pp.530-535
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    • 2017
  • Mitochondria were isolated from bird and mammals. The activity of monoamine oxidase (EC 1.4.3.4) was then measured to identify mitochondrial isolation. Lactate dehydrogenase (EC 1.1.1.27, lactate dehydrogenase, LDH) isozymes in mitochondrial fractions were analyzed by biochemical and immunochemical methods. The activity of mitochondrial LDH was lower in mammals than in bird. Therefore, the role of mitochondrial LDH seems to be more important in bird than in mammals. The concentration of protein in all tissues of bird and mammals was less in the mitochondria than in the cytosol. In the cytosol of mice and golden hamsters, testis-specific LDH $C_4$ isozyme was expressed in testis in addition to the LDH $A_4$, $A_3B$, $A_2B_2$, $AB_3$, and $B_4$ isozymes. A single LDH AB hybrid isozyme was expressed in the chicken mitochondria. In mammals, mitochondrial LDH isozymes were differed according to tissues. LDH $A_4$ and testis-specific LDH $C_4$ isozymes were expressed in the mitochondria of mice. The mitochondrial testis-specific LDH $C_4$ isozyme was expressed only in the mice. In the golden hamster mitochondria, the LDH $B_4$ isozyme functioned as a lactate oxidase. As our results show, the mitochondrial LDH seemed to be playing the different role in the bird and mammals in relation with their metabolic conditions and habitats.

BCL-2 and BAX Expression in Normal Human Endometrium (인간의 정상 자궁내막조직에서의 BCL-2와 BAX 단백질의 발현)

  • Hong, Soon-Oak;Lee, Byung-Seok;Yang, Woo-Ick;Lee, Jee-Sung;Cha, Dong-Hyon;Cho, Yong-Seon;Kim, Jeong-Yeon;Park, Ki-Hyun;Cho, Dong-Jae;Song, Chan-Ho
    • Clinical and Experimental Reproductive Medicine
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    • v.27 no.3
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    • pp.245-251
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    • 2000
  • Objective: To investigate the distribution of BCL-2, BAX proteins and DNA fragmented cells in the normal human endometrium during at each menstrual cycle in order to find out whether apoptosis regulates cyclic endometrial change. Methods: Normal endometrial tissues were obtained from 40 patients, $32{\sim}45$ year of age, all with regular menstrual cycle, who were undergoing abdominal hysterectomy for myoma of uterus or cervical intraepithelial neoplasia for the period from 1992 through 1997. Immunohistochemical staining was used to determine the expression of BCL-2 and BAX protein with paraffin-embedded tissues. Results: BCL-2 was expressed on the glandular epithelial cells and stromal cells during the proliferative phase. The intensity of BCL-2 was increased predominantly on the basal layer than the functional layer in late proliferative phase. However, BCL-2 immunoreactivity was decreased in the secretory phase. BAX was expressed predominantly during the secretory phase. The intesity was increased in late secretory phase rather than early secretory phase. DNA fragmented cells were detected in a few cells at each phase. However, it was increased during the late secretory phase. Conclusion: Apoptosis-related genes, BCL-2 and BAX, may play a role in the regulation of cyclic endometrial change.

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Improvement Effect of Corni Fructus 30% Ethanol Extract by MIA-Induced Osteoarthritis Animal Model (MIA로 골관절염 유발된 동물모델에서 산수유(山茱萸) 30% Ethanol 추출물의 개선 효과)

  • Kim, Min Ju;Lee, Jin A;Shin, Mi-Rae;Park, Hae-Jin;Roh, Seong-Soo
    • The Korea Journal of Herbology
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    • v.35 no.1
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    • pp.35-44
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    • 2020
  • Objectives : The objective of this study was to investigate the therapeutic effect of Corni Fructus 30% ethanol extract (CFE) on the monosodium iodoacetate (MIA)-induced osteoarthritis rats. Methods : The subjects were divided into 4 groups ; Normal group (N, n=10), MIA-induced osteoarthritis control group (Con, n=10), indomethacin 5 mg/kg treated group (INDO, n=10), CFE 200 mg/kg treated group (CFE, n=10). Blood and articulation tissues were collected after two weeks of drug administration. Oxidative stress was analyzed with reactive oxygen species (ROS), peroxynitrite (ONOO-). And the Nuclear factor erythroid-2 (Nrf2), heme oxygenase-1 (HO-1), superoxide dismutase (SOD), catalase, glutathione peroxidase-1/2 (GPx-1/2), Nuclear Factor Kappa B p65 (NF-κBp65), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNFα), interleukin-6 (IL-6), Interleukin 1β (IL-1β), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinases-1 (TIMP-1) were investigated by western blot. Results : The administration of CFE showed a significant reduction of changes in relative hind paw weight distribution. Reactive oxygen species (ROS) and peroxy nitrite (ONOO-) levels of articulation tissues were significantly decreased in CFE compared to the control group. Western blot measurements of Nrf2, HO-1, SOD, catalase, GPx-1/2 showed that the CFE group was increased compared to the Con group. And western blot measurements of NF-κBp65, COX-2, iNOS, TNFα, IL-6, IL-1β showed that the CFE group was reduced compared to the Con group. Also CFE group decreased MMP-1 and increased TIMP-1. Conclusion : Based on the above results, it can be seen that osteoarthritis is improved when Corni Fructus 30% ethanol extract treated.

Manganese Distribution in Brains of Sprague Dawley Rats after 60 Days of Stainless Steel Welding-Fume Exposure

  • Yu, Il-Je;Park, Jung-Duck;Park, Eon-Sub;Song, Kyung-Seuk;Han, Kuy-Tae;Han, Jeong-Hee;Chung, Yong-Hyun;Choi, Byung-Sun;Chung, Kyu-Hyuck;Cho, Myung-Haeng
    • Environmental Mutagens and Carcinogens
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    • v.23 no.3
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    • pp.85-93
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    • 2003
  • Welders working in a confined space, like in the shipbuilding industry, are at risk of being exposed to high concentrations of welding fumes and developing pneumoconiosis or other welding-fume exposure related diseases. Among such diseases, manganism resulting from welding-fume exposure remains a controversial issue, as the movement of manganese into specific brain regions has not been clearly established. Accordingly, to investigate the distribution of manganese in the brain after welding-fume exposure, male Sprague Dawley rats were exposed to welding fumes generated from manual metal arc stainless steel (MMA-SS) at concentrations of $63.6{\pm}4.1$ $mg/m^3$ (low dose, containing 1.6 $mg/m^3$ Mn) and $107.1{\pm}6.3$ $mg/m^3$ (high dose, containing 3.5 $mg/m^3$ Mn) total suspended particulates for 2 hrs per day, in an inhalation chamber over a 60-day period. Blood, brain, lungs and liver samples were collected after 2 hr, 15, 30, and 60 days of exposure and the tissues analyzed for their manganese concentrations using an atomic absorption spectrophotometer. Although dose- and time-dependent increases in the manganese concentrations were found in the lungs and livers of the rats exposed for 60 days, only slight manganese increases were observed in the blood during this period. Major statistically significant increases in the brain manganese concentrations were detected in the cerebellum after 15 days of exposure and up until 60 days. Slight increases in the manganese concentrations were also found in the substantia nigra, basal ganglia (caudate nucleus, putamen, and globus pallidus), temporal cortex, and frontal cortex, thereby indicating that the pharmacokinetics and distribution of manganese inhaled from welding fumes would appear to be different from those resulting from manganese-only exposure.

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FINITE ELEMENT ANALYSIS OF THE INFLUENCE OF ESTHETIC POSTS ON INCISORS (심미 포스트가 전치에 미치는 응력과 변위에 관한 삼차원 유한요소법적 분석)

  • Kwon Tae-Hoon;Hwang Jung-Won;Kim Sung-Hun;Shin Sang-Wan
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.5
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    • pp.582-595
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    • 2003
  • Statement of problem : Most posts are metallic, but in response to the need for a post that possesses optical properties compatible with an all-ceramic crown. an esthetic post has been developed. Although there have been many studies about the esthetic post materials, 3-dimensional finite element studies about the stress distribution of them are in rare. Purpose : The purpose of this study is to investigate comparatively the distribution of stresses of the restored, endodontically treated maxillary incisors with the esthetic post materials and the displacement on the cement layer on simulated occlusal loading by using a 3-dimensional finite element analysis model. Material and method : Four 3-dimensional finite element models were constructed in a view of a maxillary central incisor, a post, a core, and the supporting tissues to investigate the stresses in various esthetic posts and cores and the displacement on the cement layer (Model 1 ; Cast gold post and core, Model 2 ; Glass fiber post with composite core, Model 3 ; Zirconia post with composite core. Model 4 ; Zirconia post with ceramic core). Force of 300N was applied to the incisal edge and the cingulum (centric stop point) with the angle of 135-degree to the long axis of the tooth. Results : 1. The stresses and displacement on the incisal edge were higher than on the cingulum 2. The stresses in dentin were the highest in Model 2 (Glass fiber post with composite core), and the second was Model 3, the third Model 1, and the lowest Model 4. 3. The stresses in post and core were the highest in Model 4 (Zirconia post with ceramic core), and the second was Model 1, the third Model 3, and the lowest Model 2. 4. The displacement on the cement layer was the highest in Model 2 (Glass fiber post with composite core), and the second was Model 3, the third Model 1, and the lowest Model 4. Conclusion : When a functional maximum bite force was applied, the distribution of stresses or the esthetic post and core materials and the displacement on the cement layer were a little different. It seems that restoring extensively damaged incisors with esthetic post and core materials would be decided according to the remaining tooth structure.

Sodium Dependent Taurine Transport into the Choroid Plexus, the Blood-Cerebrospinal Fluid Barrier

  • Chung, Suk-Jae;Ramanathan, Vikram;Brett, Claire M.;Giacomini, Kathleen M.
    • Journal of Pharmaceutical Investigation
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    • v.25 no.3
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    • pp.7-20
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    • 1995
  • Taurine, a ${\beta}-amino$ acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine dose not cross the blood-brain barrier, we examined whether the choroid plexus, the blood-cerebrospinal fluid (CSF) barrier, plays a role in taurine transport in the central nervous system. The uptake of $[^3H]-taurine$ into ATP depleted choroid plexus from rabbit was substantially greater in the presence of an inwardly directed $Na^+$ gradient taurine accumulation was negligible. A transient in side-negative potential gradient enhanced the $Na^+-driven$ uptake of taurine into the tissue slices, suggesting that the transport process is electrogenic, $Na^+-driven$ taurine uptake was saturable with an estimated $V_{max}$ of $111\;{\pm}\;20.2\;nmole/g/15\;min$ and a $K_M\;of\;99.8{\pm}29.9\;{\mu}M$. The estimated coupling ratio of $Na^+$ and taurine was $1.80\;{\pm}\;0.122.$ $Na^+-dependent$ taurine uptake was significantly inhibited by ${\beta}-amino$ acids, but not by ${\alpha}-amino$ acids, indicating that the transporter is selective for ${\beta}-amino$ acids. Since it is known that the physiological concentration of taurine in the CSF is lower than that in the plasma, the active transport system we characterized may face the brush border (i.e., CSF facing) side of the choroid plexus and actively transport taurine out of the CSF. Therefore, we examined in vivo elimination of taurine from the CSF in the rat to determine whether elimination kinetics of taurine from the CSF is consistent with the in vitro study. Using a stereotaxic device, cannulaes were placed into the lateral ventricle and the cisterna magna of the rat. Radio-labelled taurine and inulin (a marker of CSF flow) were injected into the lateral ventricle, and the concentrations of the labelled compounds in the CSF were monitored for upto 3 hrs in the cisterna magna. The apparent clearance of taurine from CSF was greater than the estimated CSF flow (p<0.005) indicating that there is a clearance process in addition to the CSF flow. Taurine distribution into the choroid plexus was at least 10 fold higher than that found in other brain areas (e. g., cerebellum, olfactory bulb and cortex). When unlabelled taurine was co-administered with radio-labelled taurine, the apparent clearance of taurine was reduced (p<0.0l), suggesting a saturable disposition of taurine from CSF. Distribution of taurine into the choroid plexus, cerebellum, olfactory bulb and cortex was similarly diminished, indicating that the saturable uptake of taurine into these tissues is responsible for the non-linear disposition. A pharmacokinetic model involving first order elimination and saturable distribution described these data adequately. The Michaelis-Menten rate constant estimated from in vivo elimination study is similar to that obtained in the in vitro uptake experiment. Collectively, our results demonstrate that taurine is transported in the choroid plexus via a $Na^+-dependent,saturable$ and apparently ${\beta}-amino$ acid selective mechanism. This process may be functionally relevant to taurine homeostasis in the brain.

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Consideration Regarding the Breast Cancer Treatment Plan That Used Irregular Surface Compensator (ISC) (Irregular Surface Compensator (ISC)를 이용한 유방암치료계획에 관한 고찰)

  • Je, Young-Wan;Kim, Chan-Yong;Park, Heung-Deuk
    • The Journal of Korean Society for Radiation Therapy
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    • v.19 no.2
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    • pp.131-141
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    • 2007
  • Purpose: Try to compare dose distribution and lung dose of radiation treatment plan of the breast cancer that used Irregular Surface Compensator (ISC) and treatment plan that used a wedge filter. Materials and Methods: Established a treatment plan to be distributed over 95% of prescription dose (5,040 cGy) of the two tangent-half fields that used a wedge filter and ISC at a breast organization as made to breast cancer patient having an irregular surfaces after surgery. Compared high dose area and DVH, and verified a treatment plan as used film with rectangular phantom. Results: Maximum dose point in breast tissue appeared to 107.5% in case of tangent-half fields Tx plan that used a wedge filter, and lung volumes exposed above 20 Gy by 7.63%. In case of ISC, maximum dose point in breast tissue appeared to 106.4%, and lung volumes exposed above 20 Gy by 6.5%. The film measurement results that used phantom, 105$\sim$110% high dose region was distributed to the upper part and both edges of phantom. However in case of ISC, appeared by 100$\sim$105% dose conformity distribution. Conclusion: In general, the Irregular Surface Compensator (ISC) can improve the dose conformity of breast tissues, as well as reduced hot spots in the lung and in the breast. Such an advantage by using ISC technique is more beneficial for patients who have more irregular surfaces after surgery.

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