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Clinical Study of Hypophosphatemic Rickets (저인산혈성 구루병에 대한 임상적 고찰)

  • Lee Chang-Jin;Cho Hee-Yeon;Kang Ju- Hyung;Shin Choong-Ho;Ha Il-Soo;Cheong Hae-Il;Yang Sei-Won;Choe Yong
    • Childhood Kidney Diseases
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    • v.8 no.2
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    • pp.195-204
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    • 2004
  • Purpose: Hypophosphatemic rickets is a hereditary disease, characterized by hypophosphatemia due to renal phosphate wasting, impaired renal production of 1,25-dihydroxyvitamin $D_3$, rachitic bone deformities and impaired growth. The purpose of this study is to provide clinical profiles of patients with hypophosphatemic rickets in our hospital. Methods: Between July 1983 and February 2004, 56 patients were diagnosed as having hypophosphatemic rickets. The medical records of these patients were reviewed retrospectively. Clinical manifestations, family histories, laboratory data, treatment outcomes were described. Results: Fifty six patients were enrolled in this study. The average age at symptom onset and diagnosis were 20 months and 5 years respectively. Fourteen patients had family histories. The main clinical manifestations were bow legs and short stature. There was a significant negative correlation between the ages and the height z-scores at the time of diagnosis(r=-0.47, P=0.005). Initial laboratory data showed normocalcemia, hypophosphatemia, elevated serum alkaline phosphatase, decreased tubular reabsorption of phosphate and a normal range of 1,25-dihydroxyvitamin $D_3$ Radiographic examinations of bone revealed fraying, widening and cupping of the metaphyseal ends. Treatment consisted of Joulie solution and vitamin D metabolites, and resulted in improved biochemical and radiographic findings. However, height z-scores remained essentially unchanged(P=0.224). Complications of treatment were frequently observed, including hyperparathyroidism, nephrocalcinosis, and hypercalciuria. Sixteen patients had corrective osteotomy and 4 of them underwent leg lengthening together. Conclusion: There was a gap of several years between the onset of symptoms and the diagnosis. Early treatment seems to be essential to growth. For the earlier treatment, the offsprings of affected parents should be followed up closely.

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Estimation of Long-term Effects of Harvest Interval and Intensity, and Post-harvest Residue Management on the Soil Carbon Stock of Pinus densiflora Stands using KFSC Model (한국형 산림토양탄소모델(KFSC)을 이용한 수확 주기 및 강도와 수확 후 잔재물 처리방법에 따른 소나무림 토양탄소 저장량의 장기 변화 추정 연구)

  • Park, Chan-Woo;Yi, Koong;Lee, Jongyeol;Lee, Kyeong-Hak;Yi, Myong-Jong;Kim, Choonsig;Park, Gwan-Soo;Kim, Raehyun;Son, Yowhan
    • Journal of Korean Society of Forest Science
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    • v.102 no.1
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    • pp.82-89
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    • 2013
  • Harvest is one of the major disturbances affecting the soil carbon (C) dynamics in forests. However, researches on the long-term impact of periodic harvest on the soil C dynamics are limited since they requires rigorous control of various factors. Therefore, we adopted a modeling approach to determine the long-term impacts of harvest interval, harvest intensity and post-harvest residue management on soil C dynamics by using the Korean Forest Soil Carbon model (KFSC model). The simulation was conducted on Pinus densiflora S. et Z. stands in central Korea, and twelve harvest scenarios were tested by altering harvest intervals (50, 80, and 100-year interval), intensities (partial-cut harvest: 30% and clear-cut harvest: 100% of stand volume), and the residue managements after harvest (collection: 0% and retention: 100% of aboveground residue). We simulated the soil carbon stock for 400 years for each scenario. As a result, the soil C stocks in depth of 30 cm after 400 years range from 50.3 to 55.8 Mg C $ha^{-1}$, corresponding to 98.1 to 108.9% of the C stock at present. The soil C stock under the scenarios with residue retention was 2.5-11.0% higher than that under scenarios with residue collection. However, there was no significant impact of harvest interval and intensity on the soil C stock. The soil C dynamics depended on the dead organic matter dynamics derived from the amount of dead organic matter and growth pattern after harvest.

INFLUENCE OF SODIUM ASCORBATE ON MICROTENSILE BOND STRENGTHS TO PULP CHAMBER DENTIN TREATED WITH NAOCL (NaOCl로 처리된 치수강 상아질에서 sodium ascorbate가 미세인장결합강도에 미치는 영향)

  • Jeon, Soo-Yeon;Lee, Kwang-Won;Yu, Mi-Kyung
    • Restorative Dentistry and Endodontics
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    • v.33 no.6
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    • pp.545-552
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    • 2008
  • The purpose of this study was to evaluate the influence of sodium ascorbate on microtensile bond strengths of total-etching adhesive system to pulp chamber dentin treated with NaOCl. Pulp chambers of extracted human non-caries permanent molars were treated as follows: group 1, with 0.9% NaCl; group 2, with 5.25% NaOCl; group 3, with 5.25% NaOCl and 10% sodium ascorbate for 1min; group 4, with 5.25% NaOCl and 10% sodium ascorbate for 1 min and 10ml of water; group 5, with 5.25% NaOCl and 10% sodium ascorbate for 5 min; group 6, with 5.25% NaOCl and 10% sodium ascorbate for 5 min and 10ml of water; group 7, with 5.25% NaOCl and 10% sodium ascorbate for 10 min; group 8, with 5.25% NaOCl and 10% sodium ascorbate for 10 min and 10ml of water. Treated specimens were dried, bonded with a total-etching adhesive system (Single bond), restored with a composite resin(Z250) and kept for 24h at 100% humidity to measure the microtensile bond strength. NaOCl-treated group (group 2) demonstrated significantly lower strength than the other groups. No significant difference in microtensile bond strengths was found between NaCl-treated group (group 1) and sodium ascorbatetreated groups (group 3-8). The results of this study indicated that dentin treated with NaOCl reduced the microtensile bond strength of Single bond. Application of 10% sodium ascorbate restored the bond strength of Single bond on NaOCl-treated dentin. Application time of sodium ascorbate did not have a significant effect.

Structural Analysis of the North Sobaegsan Massif in the Sangun-myeon area, Bonghwa-gun, Korea (봉화군 상운면지역에서 북부 소백산육괴의 지질구조 해석)

  • 강지훈;김형식
    • The Journal of the Petrological Society of Korea
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    • v.9 no.4
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    • pp.254-270
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    • 2000
  • To clarify the geological structure of North Sobaegsan Massif in the Sangunmyeon area, Bonghwagun, Korea, where the Yecheon Shear Zone passes and the NE-SW and E-W trending structural lineaments are developed, the rock-structures of its main constituent rocks(Precambrian Won-nam Formation and Mesozoic Hornblende Granite) were examined. In this area, the geological structure was formed at least by four phases of deformation after the formation of gneissosity or schistosity of the Wonnam Formation: one deformation before D2 ductile shearing related to the for-mation of the Yecheon Shear Zone and two deformations after that. The NE-SW and E-W trending structural lineaments were formed by a giant open or gentle type of F4 fold, and their trends before D4 deformation are interpreted to be parallel to the orientation(ENE-WSW trend) of folded surface in the F4 hinge zone. The structural features of Dl-D3 deformations and their relative occurrence times are as follows. Dl deformation is formative period of the boudin structures and ENE-WSW trending isoclinal folds with sub-horizontal hinge lines and steeply inclined axial surfaces. D2 deformation is that of the mylonite foliation, stretching lineation and Z-shaped asymmetric folds related to top-to-the ENE dextral strike-slip shearing on the distinct foliations of Wonnam Formation(after intrusion of Mesozoic Hornblende Granite). D3 deformation is that of the ENE trending S-shaped asymmetric folds with sub-horizontal hinge lines and axial surfaces related to normal-slip shearing on the distinct foliations. It is expected that the result will be contributed to as valuable data for interpreting the tectonic evolution of the North Sobaegsan Massif and the Northeast Ogcheon Belt whose tectonic lineaments are changed from NE-SW to E-W trends at the Sindong-Bonghwa line.

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THE LUMINOSITY-LINEWIDTH RELATION AS A PROBE OF THE EVOLUTION OF FIELD GALAXIES

  • GUHATHAKURTA PURAGRA;ING KRISTINE;RIX HANS-WALTER;COLLESS MATTHEW;WILLIAMS TED
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.63-64
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    • 1996
  • The nature of distant faint blue field galaxies remains a mystery, despite the fact that much attention has been devoted to this subject in the last decade. Galaxy counts, particularly those in the optical and near ultraviolet bandpasses, have been demonstrated to be well in excess of those expected in the 'no-evolution' scenario. This has usually been taken to imply that galaxies were brighter in the past, presumably due to a higher rate of star formation. More recently, redshift surveys of galaxies as faint as B$\~$24 have shown that the mean redshift of faint blue galaxies is lower than that predicted by standard evolutionary models (de-signed to fit the galaxy counts). The galaxy number count data and redshift data suggest that evolutionary effects are most prominent at the faint end of the galaxy luminosity function. While these data constrain the form of evolution of the overall luminosity function, they do not constrain evolution in individual galaxies. We are carrying out a series of observations as part of a long-term program aimed at a better understanding of the nature and amount of luminosity evolution in individual galaxies. Our study uses the luminosity-linewidth relation (Tully-Fisher relation) for disk galaxies as a tool to study luminosity evolution. Several studies of a related nature are being carried out by other groups. A specific experiment to test a 'no-evolution' hypothesis is presented here. We have used the AUTOFIB multifibre spectro-graph on the 4-metre Anglo-Australian Telescope (AAT) and the Rutgers Fabry-Perot imager on the Cerro Tolalo lnteramerican Observatory (CTIO) 4-metre tele-scope to measure the internal kinematics of a representative sample of faint blue field galaxies in the red-shift range z = 0.15-0.4. The emission line profiles of [OII] and [OIII] in a typical sample galaxy are significantly broader than the instrumental resolution (100-120 km $s^{-l}$), and it is possible to make a reliable de-termination of the linewidth. Detailed and realistic simulations based on the properties of nearby, low-luminosity spirals are used to convert the measured linewidth into an estimate of the characteristic rotation speed, making statistical corrections for the effects of inclination, non-uniform distribution of ionized gas, rotation curve shape, finite fibre aperture, etc.. The (corrected) mean characteristic rotation speed for our distant galaxy sample is compared to the mean rotation speed of local galaxies of comparable blue luminosity and colour. The typical galaxy in our distant sample has a B-band luminosity of about 0.25 L$\ast$ and a colour that corresponds to the Sb-Sd/Im range of Hub-ble types. Details of the AUTOFIB fibre spectroscopic study are described by Rix et al. (1996). Follow-up deep near infrared imaging with the 10-metre Keck tele-scope+ NIRC combination and high angular resolution imaging with the Hubble Space Telescope's WFPC2 are being used to determine the structural and orientation parameters of galaxies on an individual basis. This information is being combined with the spatially resolved CTIO Fabry-Perot data to study the internal kinematics of distant galaxies (Ing et al. 1996). The two main questions addressed by these (preliminary studies) are: 1. Do galaxies of a given luminosity and colour have the same characteristic rotation speed in the distant and local Universe? The distant galaxies in our AUTOFIB sample have a mean characteristic rotation speed of $\~$70 km $s^{-l}$ after correction for measurement bias (Fig. 1); this is inconsistent with the characteristic rotation speed of local galaxies of comparable photometric proper-ties (105 km $s^{-l}$) at the > $99\%$ significance level (Fig. 2). A straightforward explanation for this discrepancy is that faint blue galaxies were about 1-1.5 mag brighter (in the B band) at z $\~$ 0.25 than their present-day counterparts. 2. What is the nature of the internal kinematics of faint field galaxies? The linewidths of these faint galaxies appear to be dominated by the global disk rotation. The larger galaxies in our sample are about 2"-.5" in diameter so one can get direct insight into the nature of their internal velocity field from the $\~$ I" seeing CTIO Fabry-Perot data. A montage of Fabry-Perot data is shown in Fig. 3. The linewidths are too large (by. $5\sigma$) to be caused by turbulence in giant HII regions.

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Development of Video Image-Guided Setup (VIGS) System for Tomotherapy: Preliminary Study (단층치료용 비디오 영상기반 셋업 장치의 개발: 예비연구)

  • Kim, Jin Sung;Ju, Sang Gyu;Hong, Chae Seon;Jeong, Jaewon;Son, Kihong;Shin, Jung Suk;Shin, Eunheak;Ahn, Sung Hwan;Han, Youngyih;Choi, Doo Ho
    • Progress in Medical Physics
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    • v.24 no.2
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    • pp.85-91
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    • 2013
  • At present, megavoltage computed tomography (MVCT) is the only method used to correct the position of tomotherapy patients. MVCT produces extra radiation, in addition to the radiation used for treatment, and repositioning also takes up much of the total treatment time. To address these issues, we suggest the use of a video image-guided setup (VIGS) system for correcting the position of tomotherapy patients. We developed an in-house program to correct the exact position of patients using two orthogonal images obtained from two video cameras installed at $90^{\circ}$ and fastened inside the tomotherapy gantry. The system is programmed to make automatic registration possible with the use of edge detection of the user-defined region of interest (ROI). A head-and-neck patient is then simulated using a humanoid phantom. After taking the computed tomography (CT) image, tomotherapy planning is performed. To mimic a clinical treatment course, we used an immobilization device to position the phantom on the tomotherapy couch and, using MVCT, corrected its position to match the one captured when the treatment was planned. Video images of the corrected position were used as reference images for the VIGS system. First, the position was repeatedly corrected 10 times using MVCT, and based on the saved reference video image, the patient position was then corrected 10 times using the VIGS method. Thereafter, the results of the two correction methods were compared. The results demonstrated that patient positioning using a video-imaging method ($41.7{\pm}11.2$ seconds) significantly reduces the overall time of the MVCT method ($420{\pm}6$ seconds) (p<0.05). However, there was no meaningful difference in accuracy between the two methods (x=0.11 mm, y=0.27 mm, z=0.58 mm, p>0.05). Because VIGS provides a more accurate result and reduces the required time, compared with the MVCT method, it is expected to manage the overall tomotherapy treatment process more efficiently.

INFLUENCE OF REBONDING PROCEDURES ON MICROLEAKAGE OF COMPOSITE RESIN RESTORATIONS (복합레진 수복 시 재접착 술식이 미세누출에 미치는 영향)

  • Lee, Mi-Ae;Seo, Duck-Kyu;Son, Ho-Hyun;Cho, Byeong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.35 no.3
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    • pp.164-172
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    • 2010
  • During a composite resin restoration, an anticipating contraction gap is usually tried to seal with low-viscosity resin after successive polishing, etching, rinsing and drying steps, which as a whole is called rebonding procedure. However, the gap might already have been filled with water or debris before applying the sealing resin. We hypothesized that microleakage would decrease if the rebonding agent was applied before the polishing step, i.e., immediately after curing composite resin. On the buccal and lingual surfaces of 35 extracted human molar teeth, class V cavities were prepared with the occlusal margin in enamel and the gingival margin in dentin. They were restored with a hybrid composite resin Z250 (3M ESPE, USA) using an adhesive AdperTM Single Bond 2 (3M ESPE). As rebonding agents, BisCover LV (Bisco, USA), ScotchBond Multi-Purpose adhesive (3M ESPE) and an experimental adhesive were applied on the restoration margins before polishing step or after successive polishing and etching steps. The infiltration depth of 2% methylene blue into the margin was measured using an optical stereomicroscope. The correlation between viscosity of rebonding agents and mciroleakage was also evaluated. There were no statistically significant differences in the microleakage within the rebonding procedures, within the rebonding agents, and within the margins. However, when the restorations were not rebonded, the microleakage at gingival margin was significantly higher than those groups rebonded with 3 agents (p < 0.05). The difference was not observed at the occlusal margin. No significant correlation was found between viscosity of rebonding agents and microleakage, except very weak correlation in case of rebonding after polishing and etching at gingival margin.

Effects of Nitrogen and phosphorus Fertilization on the Growth, Carbohydrate Contents and photosynthesis of Pinus densiflora Seedlings Exposed to Ozone in an Open-Top Chamber (질소(窒素)와 인(燐) 시비(施肥)가 Open-Top Chamber 내(內)에서 오존에 노출(露出)시킨 소나무(Pinus densiflora) 묘목(苗木)의 생장(生長), 탄수화물(炭水化物) 농도(濃度)와 광합성(光合成)에 미치는 영향(影響))

  • Bak, Jae Hyoung;Lee, Kyung Joon
    • Journal of Korean Society of Forest Science
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    • v.90 no.3
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    • pp.306-313
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    • 2001
  • The objectives of this study were to understand the physiological responses and resistance of red pine trees to ozone exposure in relation to nitrogen and phosphorus fertilization. Potted one-year-old seedlings of Pinus densiflora S. et Z. were exposed in an open-top chamber(OTC) to ozone at concentration of 0.12ppm for 3 hours daily for eight weeks with or without N and P fertilization alone or in combination. The OTC had dimensions of 2.0m in height and 2.5m in diameter, and the air in a control chamber was filtered with activated charcoal to maintain the ozone concentration below 0.02ppm. After eight weeks of ozone exposure, none of the seedlings showed any symptoms of visible injury on leaves. The seedlings fertilized with N and P in a control chamber showed 22 to 95% increase in total dry weight, and similar fertilizer effect was also noticed in an ozone chamber. Ozone treatment did not decrease the total dry weight, but increased shoot/root ratio by 14.5%. Ozone treatment increased sucrose content in the leaves by 23%, but decreased sucrose content in roots by 20% regardless of N or P application. Starch content in the leaves was not affected by either ozone or fertilizer. However, starch content in the roots was decreased by 41% by ozone treatment. Chlorophyll content in the leaves was increased by 70% by N application, but was not affected by ozone treatment. Nitrogen and P fertilization stimulated net photosynthesis by 80% in a control chamber, but stimulatory effect of N and P on net photosynthesis was 22.3% less in an ozone chamber. Net photosynthesis of the seedlings with no fertilization was not affected by ozone treatment. Based on the observed interactions between N, P, and ozone, it was concluded that the stimulatory effect of fertilization on growth of Pinus densiflora would be decreased by ozone treatment, but fertilization would increase resistance to ozone by re-allocation of increased carbohydrates.

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Characteristics of Fish Community in Gap Stream by Habitat Type (서식처 유형에 따른 갑천의 어류군집 특성)

  • Lee, Dong-Jun;Byeon, Hwa-Kun;Choi, Jun-Kill
    • Korean Journal of Ecology and Environment
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    • v.42 no.3
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    • pp.340-349
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    • 2009
  • The natural type section of Gap Stream was divided into 7 sites, such as, closed pool, runs, riffle, opened pool, pool, reek-scattered riffle, and Dam-type pool. The ecological characteristics of fish community at each site was examined from April, 2007 to October, 2008. During the survey period, 29 species belonging to 8 families were collected, and Carassius auratus (St. 1), Coreoleuciscus splendidus (St. 3), Acheilognathus lanceolatus (St. 4) and Zacco platypus (St. 2, 5, 6, 7) were characteristic species that represent each habitat. The species of C. auratus preferred physical habitat with sand-bottom pool, moderate depth of 65$\sim$90 cm, and stagnant water. The species of C. splendidus mainly preferred physical habitat with cobbles and pebbles are scattered riffles (St. 3), moderate depth of 65$\sim$90 cm, and flow velocity is 0.14$\sim$0.85 m $sec^{-1}$. It also preferred where concentration of BOD, COD, TN, TP and SS is low and DO's value is high, because the flow velocity is fast. A. lanceolatus preferred where the depth of water is low (3$\sim$44 cm) like an opened pool (St. 4) and the flow velocity is slow (0.01$\sim$0.02 m $sec^{-1}$). Z. platypus dominated in a variety of habitats such as runs (St. 2), pool (St. 5), rock-scattered riffles (St. 6) and D-type pool (St. 7), and it preferred places where flow is abundant and riverbed structure is diverse. On the other hand, 4 individuals of Iksookimia choii appeared at reek-scattered riffles (St. 6). I. choii appeared in this research lived in where the width of river is 24 m, the depth of water is 3$\sim$35 cm and the flow velocity is 0.01$\sim$0.49 m $sec^{-1}$, and riverbed structure was diversely formed with boulder to sand. Also, water temperature, EC, BOD, COD, TN and TP was low, but concentrations of DO and SS were high comparatively. Therefore, it seems that I. choii can live only in physical and chemical environment with similar conditions.

Deformation History of Precambrian Metamorphic Rocks in the Yeongyang-Uljin Area, Korea (영양-울진 지역 선캠브리아기 변성암류의 변형작용사)

  • Kang Ji-Hoon;Kim Nam Hoon;Park Kye-Hun;Song Yong Sun;Ock Soo-Seok
    • The Journal of the Petrological Society of Korea
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    • v.13 no.4
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    • pp.179-190
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    • 2004
  • Precambrian metamorphic rocks of Yeongyang-Uljin area, which is located in the eastern part of Sobaegsan Massif, Korea, are composed of Pyeonghae, Giseong, Wonnam Formations and Hada leuco granite gneisses. These show a zonal distribution of WNW-ESE trend, and are intruded by Mesozoic igneous rocks and are unconformably overlain by Mesozoic sedimentary rocks. This study clarifies the deformation history of Precambrian metamorphic rocks after the formation of gneissosity or schistosity on the basis of the geometric and kinematic features and the forming sequence of multi-deformed rock structures, and suggests that the geological structures of this area experienced at least four phases of deformation i.e. ductile shear deformation, one deformation before that, at least two deformations after that. (1) The first phase of deformation formed regional foliations and WNW-trending isoclinal folds with subhorizontal axes and steep axial planes dipping to the north. (2) The second phase of deformation occurred by dextral ductile shear deformation of top-to-the east movement, forming stretching lineations of E-W trend, S-C mylonitic structure foliations, and Z-shaped asymmetric folds. (3) The third phase deformation formed I-W trending open- or kink-type recumbent folds with subhorizontal axes and gently dipping axial planes. (4) The fourth phase deformation took place under compression of NNW-SSE direction, forming ENE-WSW trending symmetric open upright folds and asymmetric conjugate kink folds with subhorizontal axes, and conjugate faults thrusting to the both NNW and SSE with drag folds related to it. These four phases of deformation are closely connected with the orientation of regional foliation in the Yeongyang-Uljin area. 1st deformation produced regional foliation striking WNW and steeply dipping to the north, 2nd deformation locally change the strike of regional foliation into N-S direction, and 3rd and 4th deformations locally change dip-angle and dip-direction of regional foliation.