• Title/Summary/Keyword: body factor

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The Influence of Breakfast Size to Metabolic Risk Factors (아침식사량이 대사위험요인에 미치는 영향)

  • Kim, Yun-Jin;Lee, Jeong-Gyu;Yi, Yu-Hyeon;Lee, Sang-Yeoup;Jung, Dong-Wook;Park, Seon-Ki;Cho, Young-Hye
    • Journal of Life Science
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    • v.20 no.12
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    • pp.1812-1819
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    • 2010
  • Skipping breakfast is a risk factor closely related to metabolic syndrome and obesity. We analyzed the relationship between breakfast size, metabolic syndrome and obesity. The study included 5,548 adults who visited a health promotion center at Pusan National University from January to November of 2006. Subjects were divided into four groups according to breakfast size - skipper group (no breakfast), small intake group, medium intake group and large intake group. 959 (17.3%) of the 5548 subjects were included in the Skipper group. Intake of daily calories, proteins, carbohydrates and fats was the lowest in the Skipper group. Breakfast size increased linearly with an increased intake of daily calories, proteins, carbohydrates and fats. Body mass index ($23.4\;kg/m^2$) and waist circumference (79.6 cm) were the lowest in the Small intake group. In the Small intake group, triglycerides, fasting plasma glucose, systolic blood pressure and diastolic blood pressure were the lowest, and high density lipoprotein cholesterol levels were the highest. The number of metabolic risk factors was the lowest in Small intake group. Odds ratio of metabolic syndrome (Odds ratio=0.612) was the lowest in Small intake group. Along with increasing breakfast size, the odds ratio also increased. In this study, breakfast size was found to influence metabolic risk factors. Skipping breakfast worsened metabolic risk factors, while a small breakfast size had a favorable effect on metabolic risk factors.

The Analysis of Blood Glucose Level Difference According to the Exact Use of Blood Glucose Measurement Test Strips in $^{18}F$-FDG Wholebody PET ($^{18}F$-FDG를 이용한 전신 PET 검사에서 혈당 측정 검사지의 정확한 사용에 따른 혈당 수치의 차이 분석)

  • Park, Soon-Ki;Lee, Nam-Ki;NamGung, Chang-Kyung;Jung, Woo-Young
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.2
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    • pp.100-103
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    • 2010
  • Purpose: $^{18}F$-FDG wholebody PET is to evaluate the tumor using glucose metabolism. The blood glucose level is important factor that affects on a result of examination. High glucose levels may interfere with tumor targeting due to competitive inhibition of FDG uptake by D-glucose. The blood glucose level measurement test strips used in the blood glucose measurement are classified into the capillary blood measurement test strips and general purpose measurement test strips that can measure the venous blood and capillary blood altogether depends on cases. The purpose of the study was to compare the blood glucose measurements between simultaneously obtained capillary and venous blood samples using the capillary blood measurement test strips, general purpose measurement test strips. Materials and Methods: A total of 46 subjects (32 males, 14 females) with a mean age of $57.3{\pm}12.3$ years were enrolled. The blood glucose estimation was performed with a Optium Xceed Glucometer (Abbott). Simultaneous capillary and venous blood samples were obtained from each subject. The blood glucose levels were measured using the capillary blood measurement test strips and general purpose measurement test strips. The capillary and venous measurements were compared using a pared t-test. Results: The mean capillary and venous glucose values using the general purpose measurement test strips were $95.2{\pm}12.4$ mg/dL and $104.1{\pm}14.4$ mg/dL, giving a statistically significant difference (p<0.001) between the mean values for the capillary and venous glucose samples (9.0 mg/dL; 95% confidence interval (CI) -11.2 to -6.7). The mean capillary and venous glucose values using the capillary blood measurement test strips were $91.5{\pm}13.6$ mg/dL and $108.6{\pm}16.2$ mg/dL, giving a statistically significant difference (p<0.001) between the mean values for the capillary and venous glucose samples (16.6 mg/dL; 95% CI -20.2 to -13.0). Conclusion: When measuring the blood glucose level before $^{18}F$-FDG PET examination, since the incorrect blood glucose level can be measured, it should note to measure the blood glucose level of the venous blood by the capillary blood measurement test strips. Therefore the measurement variation can be reduced to fulfill the standardized measurement procedure with the suitable measurement test strips, the preparation of the PET examination will be able to be clearly confirmed. In addition, the standardized procedure of the following measurement on the area which is same at all times the blood area in the blood glucose measurement among a capillary or a vein will be needed.

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Recent Advancement in the Differentiation of Tissues and Organs and Regulation of Gene Expression (조직.기관의 분화와 유전자 발현의 조절, 최근의 진보)

  • Harn, Chang-Yawl
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.1
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    • pp.1-35
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    • 1997
  • Fertilized egg, by successive cell divisions, differentiates into different tissues and organs with various structures and functions. Different cells and tissues contain different proteins, products of selective gene expression. Not all the genes in any genomes are equally active, temporal and spatial gene expression being the general rule. Present paper attempts to review the tanscriptional mechanisms or the initiations of transcription from several angles. In some of the organisms the genes in the process of transcription or the genes in the inactive state can be seen under the light microscope. Some bands of Drosophila polytene chromosomes may exhibit a swollen or puff appearance under certain conditions. A puff, unfolded or decondensed form of chromomere, represents sets of intense transcriptional activity or RNA synthesis. The heterochromatic X chromosome whose genes remain inactive in the female mammals can be visualized as a dark staining structure called Barr body, Configuration of chromatin differs between transcribed and nontranscribed chromatin. Modification to the chromatin facilitates RNA synthesis. The movement of large polymerase molecule along the DNA would probably be facilitated if some modifications of the chromatin configuration is effected. Methylation of cytosines in CG sequences is associated with inactive genes. Methylation can play a role in determination of mammalian cells during embryogenesis. Demethylation is necessary for the gene to be expressed during development A histone modification that is also known to be correlated with transcriptional capacity of chromatin is acetylation of the lysine residues of the core histones. Chromatin containing a high level of histone acetylation is very sensitive to DNase 1. For the transcription to occur TBP must first bind to the TATA box. Another TF, TF IIB, then binds to the promoter-TBP complex, facilitating the access of RNA polymerase to the transcription initiation site. As recently as eight years ago researchers assumed that histones were irrelevant to the regulation of gene expression. Histones combine with the DNA to form nucleosome of the chromatin. Histones are vital participant in gene regulation. Histone and basal factors compete for access to TATA box. When DNA is exposed to basal factors before histones are introduced, the basal factors assemble on TATA boxes preventing the access of histones, allowing transcription to occur, for transcription to begin, activator protein at the upstream activation sequence or enhancer must interact with the tail of histone H4 at TATA box and cause the histone role particle to dissociate from the TATA box leading to partial breakup of the histone core particle and allowing the basal factors to bind to the TATA box. New concept of genomic flux in contrast to the old concept of static genome has been developed based on the powerful new molecular techniques. Genomic changes such as repetitive DNAs and transposable elements, it is assumed but not yet proved, may affect some of the developmental patterns that characterize particular cells, tissues, organs, and organisms. In the last decade or so remarkable achievement have been made in the researches of the structures and functions of TFs and the specific target sequences located in promoters or enhancers where these TFs bind. TFs have independent domains that bind DNA and that activate transcription. DNA binding domain of TFs serves to bring the protein into the right location. There are many types of DNA binding domains. Common types of motifs can be found that are responsible for binding to DNA. The motifs are usually quite short and comprise only a small part of the protein structure. Steroid receptors have domains for hormone binding, DNA binding, and activating transcription. The zinc finger motif comprises a DNA binding domain. Leucine zipper consist of a stretch of amino acids with a leucine residue in every seventh position Two proteins form a dimer because they interact by means of leucine zippers on similar α-helical domain. This positions their DNA binding basic domains for interaction with the two halves of a DNA sequence with dyad symmetry of TGACTCA, ACTGAGT.

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Prevalence and Risk Factors of the Gallbladder Polyps Diagnosed by Ultrasound (복부초음파검사로 진단된 담낭용종의 유병률과 위험인자 분석)

  • LEE, Mi-Hwa;Cho, Pyong-Kon;Kwon, Duck-Moon
    • Journal of radiological science and technology
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    • v.38 no.2
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    • pp.127-134
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    • 2015
  • This study was designed to determine the prevalence of gallstones in the last three years and evaluate the associated risk factors in the population who underwent health screening. Although there are many studies reporting the prevalence and risk factors of GB polyp, the results varied among each report. The aims of this study were to evaluate the prevalence rate and risk factors of GB polyp, colon polyp and fatty liver in the population who underwent health screening. The study population consisted of 4,877 visited the health promotion center in Dalseogu, Daegu in Korea from January 2011 to December 2013. Each participant in the study had their biliary system gallbladder examined using ultrasonography. The prevalence of GB polyp was evaluated along with age, gender, metabolic syndrom, body mass index (BMI), Fatty liver, Colon polyp. A showed of total 383 (7.9%) people were found to have GB polyps. The prevalence of sex among 256 (9.8%) patients men and 127 (5.6%) women which showed significantly higher in male than in female subjects(p=0.001). The mean size of the GB polyps 4.92 mm (1.6-17 mm). The sizes of most GB polyps (73.6%) were less than 10 mm in diameter. 122 subjects (31.28%) had multiple GB polyps which 2 or more polyps and 261 subjects (68.2%) had single polyp. Independent risk factors related with GB polyp were male gender (OR 0.551, p<0.001), overweight that BMI above $23kg/m^2$ (OR 0.713, p=0.002) triglyceride (OR 0.571, P<0.001), metabolic syndrome (OR 0.049, p=0.033) and colon polyp (OR 1.409, p=0.002). In spite of the conclusion, the prevalence GB polyp was higher than previous Korea and other country reports. The GB polyp in a healthy population was results as 7.9%. The risk factors of GB polyps were found to be male, being overweight, triglyceride, metabolic syndrome and colon polyp. Not only the subject of a health examination is needed but, a further study of the general public when possible.

Kinematical Analysis of Heel-Brake Stop in Inline Skate (인라인 스케이트(Inline Skate) 힐 브레이크(Heel-Brake) 정지에 관한 운동학적 분석)

  • Han, Jae-Hee;Lim, Yong-Kyu
    • Korean Journal of Applied Biomechanics
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    • v.15 no.2
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    • pp.11-20
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    • 2005
  • This study has a purpose on contributing to apprehend safe and right way to stop to the inline skate beginners and to the instructors who teaches line skating on the basis for the result of the kinematical analysis on Heel brake stop movement of the inline skate, focusing on the displacement on COG, angle displacement of ankle joint, angle displacement of knee joint, angle displacement of hip joint, using a 3D image method by DLT. To achieve this goal, we analysed the kinematical factor of the 3 well-trained inline skating instructors and obtained the following results. 1. During the movement of heel-brake stop, when strong power was given to a stable and balanced stop and the lower limbs, if the physical centroid is lowered the stability increases, and if it is placed high from the base surface, as the stability decreases compared to the case of low physical centroid, we should make a stop by placing a physical centroid in the base surface and lowering the hight of physical centroid. 2. To make a stable and balanced stop and to provide a strong power to the lower limbs, it is advisable to make a stop by decreasing an angle displacement of ankle joint during a "down" movement. In case of the left ankle joint, in all events and phases the dorsiflexion angle showed a decrease. Nevertheless, in the case of the right ankle joint, the dorsiflexion angle shows an increase after a slight decrease. The dorsiflexion angle displacement of ankle joint can be diminished because of the brake pad of the rear axis frame of the right side inline skate by raising a toe, but cannot be more decreased if certain degree of an angle is made by a brake pad touching a ground surface. To provide a power to a brake pad, it is recommended to place a power by lowering a posture making the dorsiflexion angle of the left ankle joint relatively smaller than that of the right ankle. 3. To make a stable and balanced stop and to add a power to a brake pad, the power must be given to the lower limbs in lowering the hight of physical centroid. For this, it is recommended to make a down movement by decreasing the flexion angle of a knee joint and it is necessary to make a down movement by a regular decrease of the angle displacement of knee joint rather than a swift down movement in every event and phase. 4. The right angle displacement of hip joint is made by lowering vertically the hight of physical centroid as leaning slightly forward. If too narrow angle displacement of hip joint is made by leaning forward too much, the balance is lost during the stop by placing the center in front. To make a stable and balance stop and to place a strong power to the lower limbs, it is recommendable to make a narrow angle by lower the hip joint angle. However, excessive leaning of the upper body to make the angle too narrow, can cause an instable stop and loss of physical centroid. After this study, it is considered to assist the kinematical understanding during the heel brake stop movement of the inline skate, and, to present basic data in learning a method of stable and balanced stop for the inline skating beginners or for the inline skate instructors in the present situation of the complete absence of the study in inline skating.

Risk Factor Analysis for $SaO_2$ Instability after Systemic-pulmonary Shunt (전신-폐 단락술 후 산소포화도의 불안정성의 위험인자 분석)

  • Jung Sung-Ho;Yun Sok-Won;Park Jung-Jun;Seo Dong-Man;Kim Young-Hwue;Ko Jae-Kon;Park In-Sook;Yun Tae-Jin
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.277-283
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    • 2005
  • Arterial oxygen saturation $(SaO_2)$ instability frequently takes place after systemic-pulmonary shunt without shunt occlusion. We analyzed actual incidence and risk factors for $SaO_2$ instability after shunt operations, and possible mechanisms were speculated on. Material and Method: Ninety three patients, who underwent modified Blalock-Taussig shunt from January 1996 to December 2000, were enrolled in this study. Adequacy of shunt was verified in all patients, either by ensuing one ventricle or biventricular repair later on or by appropriate pulmonary artery growth on postoperative angiogram. Age, body weight, hemoglobin level at operation were 3 day to 36 years (median: 1.8 months), 2.5kg to 51kg (median: 4.1kg) and $10.7\~24.3$ gm/dL (median: 15.2 gm/dL) respectively. Preoperative diagnoses were functional single ventricle with pulmonary stenosis or atresia in 39, tetralogy of Fallot in 38 and pulmonary atresia with intact ventricular septum in 16. Pulmonary blood flow (PBF) was maintained pre-operatively by patent ductus or previous shunt in 64 and by forward flow through stenotic right ventricular outflow tract (RVOT) in 29. $SaO_2$ instability was defined as $SaO_2$ less than $50\%$ for more than 1 hour with neither anatomic obstruction of shunt nor respiratory problem. Result: 10 patients $(10.7\%)$ showed $SaO_2$ instability after shunt operation. After shunt occlusion was ruled out by echocardiogram, they received measures to lower pulmonary vascular resistance (PVR), which worked within a few hours in all patients. Risk factors for $SaO_2$ instability included older age at operation (p=0.039), lower preoperative $SaO_2$ (p=0.0001) and emergency operation (p=0.001). PBF through stenotic RVOT showed marginal statistical significance (p=0.065). Conclusion: $SaO_2$ instability occurs frequently after shunt operation, especially in patients with severe hypoxia pre-operatively or unstable clinical condition necessitating emergency operation. Temporary elevation of pulmonary vascular resistance is a possible mechanism in this specific clinical setting.

Investigation on Inhibitory Effect of ErmSF N-Terminal End Region Peptide on ErmSF Methyltansferase Activity In Vivo Through Development of Co-Expression System of Two Different Proteins in One Cell (서로 다른 두 단백질의 세포 내 동시 발현 체계의 개발을 통한 ErmSF에서 특이적으로 발견되는 N-Terminal End Region (NTER)을 포함하는 펩타이드의 생체내에서의 ErmSF 활성 억제 효과 검색)

  • Jin, Hyung-Jong
    • Korean Journal of Microbiology
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    • v.47 no.3
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    • pp.200-208
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    • 2011
  • Most problematic antibiotic resistance mechanism for MLS (macrolide-lincosamide-streptogramn B) antibiotics encountered in clinical practice is mono- or dimethylation of specific adenine residue at 2058 (E. coli coordinate) of 23S rRNA which is performed by Erm (erythromycin ribosome resistance) protein through which bacterial ribosomes reduce the affinity to the antibiotics and become resistant to them. ErmSF is one of the four gene products produced by Streptomyces fradiae to be resistant to its own antibiotic, tylosin. Unlike other Erm proteins, ErmSF harbors idiosyncratic long N-terminal end region (NTER) 25% of which is comprised of arginine well known to interact with RNA. Furthermore, NTER was found to be important because when it was truncated, most of the enzyme activity was lost. Based on these facts, capability of NTER peptide to inhibit the enzymatic activity of ErmSF was sought. For this, expression system for two different proteins to be expressed in one cell was developed. In this system, two plasmids, pET23b and pACYC184 have unique replication origins to be compatible with each other in a cell. And expression system harboring promoter, ribosome binding site and transcription termination signal is identical but disparate amount of protein could be expressed according to the copy number of each vector, 15 for pACYC and 40 for pET23b. Expression of NTER peptide in pET23b together with ErmSF in pACYC 184 in E. coli successfully gave more amounts of NTER than ErmSF but no inhibitory effects were observed suggesting that there should be dynamicity in interaction between ErmSF and rRNA rather than simple and fixed binding to each other in methylation of 23S rRNA by ErmSF.

DEVELOPMENT OF BIOCOMPATIBLE DRESSING MATERIAL MADE OF COLLAGEN AND AMNIOTIC MEMBRANE AND WOUND HEALING EXPERIMENT IN RAT (양막과 콜라겐을 이용한 생체 적합 드레싱 소재 개발 및 백서 창상치유 실험)

  • Ahn, Kang-Min;Lee, Ji-Ho;Lee, Ui-Lyong;Lee, Jong-Ho;Lee, Jong-Won;Kim, Sung-Po;Yang, Eun-Kyung;Kim, Ki-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.3
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    • pp.189-199
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    • 2006
  • Purpose of study: Partial thickness skin graft is the golden standard regimen for full-thickness skin defect caused by burn or trauma. However, in case of extensive burns of more than 50% of total body surface area, the donor site is not sufficient to cover all defects. As a second choice, allograft, xenograft and synthetic materials have been used to treat skin defect. Among them the amniotic membrane(AM) was used as a biological dressing for centuries because of its potential for wound healing. In this study, quantification of EGF in AM and effect of AM-collagen complex on full thickness skin defects was examined. Materials & Methods: The concentration of EGF in fresh, deep frozen and freeze-dried AM was evaluated by ELISA. EGF-R immunostaining was performed in freeze-dried AM. SD rats weighing 250${\sim}$300g was used for wound healing experiment. Three full thickness skin defects(28mm diameter) were made on dorsal surface of SD rat. The control group was covered by Vaselin gauze and AM-collagen complex and $Terudermis^{(R)}$. was grafted in two other defects. Healing area, Cinamon's score were evaluated before biopsy. Grafted sites were retrieved at 3 days, 1 week, 2 weeks and 4 weeks after operation. H & E and Factor VIII immunohistochemical stain was performed to evaluate the microscopic adhesion and structural integrity and microvessel formation. Results: 1. EGF concentration of fresh, deep frozen and freeze-dried AM showed similar level and EGF-R was stained in epithelial layer of freeze-dried AM. 2. At 4 weeks after grafting, the healing area of AM-collagen and Terudermis group was 99.29${\pm}$0.71% and 99.19${\pm}$0.77 of original size. However, that of control group was 24.88${\pm}$2.90. 3. The Cinamon's score of AM-Collagen and $Terudermis^{(R)}$. group at 4 weeks was 15.6${\pm}$1.26 and 14.6${\pm}$3.13 and that of control group was 3.7${\pm}$0.95. Significant difference was observed among control and experimental groups(p<0.05). 4. Histologic examination revealed that AM protected leukocyte infiltration and epithelial migration was nearly completed at 4 weeks. $Terudermis^{(R)}$. group showed mild neutrophil infiltration until 2 weeks and completion of epithelization at 4 weeks. Control group showed massive leukocyte infiltration until 4 weeks. 5. Microvessels were increased sharply at 1 week and control group at 1 and 4 week showed significant differences with $Terudermis^{(R)}$. group of same interval(p<0.05) but no differences were found with AM group(p<0.05). Conclusion: EGF and EGF-R were well preserved in freeze-dried AM. AM attached to collagen acted as excellent biologic dressing which had similar effect with $Terudermis^{(R)}$. AM showed anti-inflammatory action and healing was completed at 4 weeks after full-thickness skin defect.

Sequential 1H MR Spectroscopy(MRS) Studies of Kaolin-Induced Hydrocephalic Cat Brain (Kaolin 유발 고양이 수두증 모델에서 양자 자기공명 분광상의 경시적 변화)

  • Kim, Myung Jin;Hwang, Sung Kyoo;Hwang, Jeong Hyun;Chang, Yongmin;Kim, Yong Sun;Kim, Seung Lae
    • Journal of Korean Neurosurgical Society
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    • v.29 no.11
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    • pp.1421-1428
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    • 2000
  • Objectives : The aim of this study is to evaluate the sequential metabolic changes in experimental hydrocephalus and the clinical applicability to the diagnosis and prognosis of hydrocephalus using proton MR spectroscopy. Methods : Hydrocephalus was experimentally induced in 30 cats(2-3kg body weight) by injecting 1ml of sterile kaolin suspension(250mg/ml) into the cisterna magna. Proton MRS was performed with a 1.5 T MRI/MRS unit (Vision Plus, Siemens) at pre-treatment and at 1, 3, 7, 14, 21, and 28 days after the kaolin injection. PRESS(TR/TE=1500/270msec) technique was employed. The major metabolites which include N-acetyl aspartate (NAA), creatine(Cr), choline(Cho), and lactate(Lac) were quantitatively analyzed and the relative concentrations ratios were evaluated. Multislice $T_2$-weighted images were also obtained using fast spin echo sequence(TR/TE= 2500/96msec) to monitor the morphologic changes along with progression of hydrocephalus. Results : Hydrocephalus was successfully induced in all 30 cats. Twenty five cats died within 3 days and one at the end of the second week. In all animals, the NAA/Cr ratios initially decreased during the acute stage. In 4 surviving cats, the NAA/Cr ratios initially decreased during the acute stage(<14 days) and then gradually increased to the prekaolin level as follows : pre-kaolin($1.49{\pm}0.04$), day 1($1.11{\pm}0.07$), day 7($1.17{\pm}0.04$), day 14($1.40{\pm}0.03$), day 21 ($1.46{\pm}0.06$), day 28($1.43{\pm}0.03$). These levels were relatively well correlated with the symptomatologic improvement. Lactate peak, which reflects the evidence of ischemia, did not appear throughout the entire period except in one case which expired at the end of the second week. Conclusions : The NAA/Cr ratio of the sequential proton MRS in kaolin-induced hydrocephalic cats reflects a metabolic aspect of the hydrocephalus at each stage. A decreased NAA level at the early stage is from both neuronal and axonal damage which may provide diagnostic information in the acute stage of hydrocephalus. In addition, the initial fall of NAA/Cr ratio and recovery in the late stage, when no lactate peak emerges, may suggest that the main insult of the parenchyma is not to the neuron itself but to the axon, which may be related to a good prognosis. However, emergence of the lactate peak and unrecoverable NAA/Cr at the end of the acute phase may be a poor prognostic factor. In the chronic stage, recovery of NAA/Cr ratio may provide a diagnostic clue for the differentiation between hydrocephalus and cortical atrophy.

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High-resolution Spiral-scan Imaging at 3 Tesla MRI (3.0 Tesla 자기공명영상시스템에서 고 해상도 나선주사영상)

  • Kim, P.K.;Lim, J.W.;Kang, S.W.;Cho, S.H.;Jeon, S.Y.;Lim, H.J.;Park, H.C.;Oh, S.J.;Lee, H.K.;Ahn, C.B.
    • Investigative Magnetic Resonance Imaging
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    • v.10 no.2
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    • pp.108-116
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    • 2006
  • Purpose : High-resolution spiral-scan imaging is performed at 3 Tesla MRI system. Since the gradient waveforms for the spiral-scan imaging have lower slopes than those for the Echo Planar Imaging (EPI), they can be implemented with the gradient systems having lower slew rates. The spiral-scan imaging also involves less eddy currents due to the smooth gradient waveforms. The spiral-scan imaging method does not suffer from high specific absorption rate (SAR), which is one of the main obstacles in high field imaging for rf echo-based fast imaging methods such as fast spin echo techniques. Thus, the spiral-scan imaging has a great potential for the high-speed imaging in high magnetic fields. In this paper, we presented various high-resolution images obtained by the spiral-scan methods at 3T MRI system for various applications. Materials and Methods : High-resolution spiral-scan imaging technique is implemented at 3T whole body MRI system. An efficient and fast higher-order shimming technique is developed to reduce the inhomogeneity, and the single-shot and interleaved spiral-scan imaging methods are developed. Spin-echo and gradient-echo based spiral-scan imaging methods are implemented, and image contrast and signal-tonoise ratio are controlled by the echo time, repetition time, and the rf flip angles. Results : Spiral-scan images having various resolutions are obtained at 3T MRI system. Since the absolute magnitude of the inhomogeneity is increasing in higher magnetic fields, higher order shimming to reduce the inhomogeneity becomes more important. A fast shimming technique in which axial, sagittal, and coronal sectional inhomogeneity maps are obtained in one scan is developed, and the shimming method based on the analysis of spherical harmonics of the inhomogeneity map is applied. For phantom and invivo head imaging, image matrix size of about $100{\times}100$ is obtained by a single-shot spiral-scan imaging, and a matrix size of $256{\times}256$ is obtained by the interleaved spiral-scan imaging with the number of interleaves of from 6 to 12. Conclusion : High field imaging becomes increasingly important due to the improved signal-to-noise ratio, larger spectral separation, and the higher BOLD-based contrast. The increasing SAR is, however, a limiting factor in high field imaging. Since the spiral-scan imaging has a very low SAR, and lower hardware requirements for the implementation of the technique compared to EPI, it is suitable for a rapid imaging in high fields. In this paper, the spiral-scan imaging with various resolutions from $100{\times}100$ to $256{\times}256$ by controlling the number of interleaves are developed for the high-speed imaging in high magnetic fields.

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