1.The Magnetic Relaxation Properties of DTPA-bis(4-carboxycyclohexyl) amide Paramagnetic Gd-chelates.
In Sung KIM ; Young Ju LEE ; Jae Jun LEE ; Ju Hyun KIM ; Yoo Kyung KIM ; Dutta SUJIT ; Suk Kyung KIM ; Tae Jeong KIM ; Yongmin CHANG ; Duk Sik KANG
Journal of the Korean Society of Magnetic Resonance in Medicine 2006;10(1):20-25
PURPOSE: To evaluate the NMR relaxation properties of newly developed high performance paramagnetic. MATERIALS AND METHODS: 4-aminomethylcyclohexane carboxylic acid (0.63 g, 4 mmol) was mixed with the suspension solution of DMF (15 mL) and DTPA-bis-anhydride (0.71 g, 2 mmol) to synthesize the ligand. The ligand was then mixed with Gd2O3 (0.18 g, 0.5 mmol) to synthesize Gd-chelate. For the measurement of magnetic relaxivity of paramagnetic compounds, the compounds were diluted to 1mM and then the relaxation times were measured at 1.5T(64 MHz). Inversion-recovery pulse sequence was employed for T1 relaxation measurement and CPMG(Carr-Purcell-Meiboon-Gill) pulse sequence was employed for T2 relaxation measurement. Using MATLAB(Version 7.1) program, T1 magnetic relaxation map, R1 map, T2 magnetic relaxation map and R2 map were developed to represent magnetic relaxation time and magnetic relaxivity as image. RESULTS: Compared to R1=4.9 mM(-1) sec(-1) and R2= 4.8 mM(-1) sec(-1) of Omniscan (Gadodiamide), which is commercially available paramagnetic MR agent, R1 of SUK090(Gd-C32H74N5O24) was 12.46 mM(-1) sec(-1) and R1 of SUK091(Gd-C34H78N5O24) was 12.77 mM(-1) sec(-1). However, R1 of SUK092(Gd-C30H56N5O17) was decreased to 2.09 mM(-1) sec(-1). In case of R2, SUK090(Gd-C32H74N5O24) was 8.76 mM(-1) sec(-1) and SUK091(Gd-C34H78N5O24) was 7.60 mM(-1) sec(-1) whereas SUK092(Gd-C30H56N5O17) CONCLUSION: Among three new paramagnetic complexes, SUK090(Gd-C32H74N5O24) and SUK091(Gd-C34H78N5O24) showed higher T1, T2 magnetic relaxation rates than that of commercially available paramagnetic MR agent and thus expected to have more contrast enhancement effect.
Relaxation*
2.Changes in force associated with the amount of aligner activation and lingual bodily movement of the maxillary central incisor.
Xiaowei LI ; Chaochao REN ; Zheyao WANG ; Pai ZHAO ; Hongmei WANG ; Yuxing BAI
The Korean Journal of Orthodontics 2016;46(2):65-72
OBJECTIVE: The purposes of this study were to measure the orthodontic forces generated by thermoplastic aligners and investigate the possible influences of different activations for lingual bodily movements on orthodontic forces, and their attenuation. METHODS: Thermoplastic material of 1.0-mm in thickness was used to manufacture aligners for 0.2, 0.3, 0.4, 0.5, and 0.6 mm activations for lingual bodily movements of the maxillary central incisor. The orthodontic force in the lingual direction delivered by the thermoplastic aligners was measured using a micro-stress sensor system for the invisible orthodontic technique, and was monitored for 2 weeks. RESULTS: Orthodontic force increased with the amount of activation of the aligner in the initial measurements. The attenuation speed in the 0.6 mm group was faster than that of the other groups (p < 0.05). All aligners demonstrated rapid relaxation in the first 8 hours, which then decreased slowly and plateaued on day 4 or 5. CONCLUSIONS: The amount of activation had a substantial influence on the orthodontic force imparted by the aligners. The results suggest that the activation of lingual bodily movement of the maxillary central incisor should not exceed 0.5 mm. The initial 4 or 5 days is important with respect to orthodontic treatment incorporating an aligner.
Incisor*
;
Relaxation
3.Firing Behavior of Motor Unit in Voluntary Relaxation Derecruitment Pattern in Slow and Fast Relaxations.
Won Hee SEO ; Sang Bae HA ; Yoshihisa MASAKADO ; Naoichi CHINO
Journal of the Korean Academy of Rehabilitation Medicine 1997;21(2):429-434
No abstract available.
Fires*
;
Relaxation*
4.The Time of Neostigmine Antagonism for the Rapid Recovery of Profound Muscle Relaxation in Rabbits.
Yoon Kee KIM ; Seon Eek HWANG ; Kyo Sang KIM ; Se Ung CHON
Korean Journal of Anesthesiology 1996;30(5):534-541
BACKGROUND: A question was whether it was preferable to give the reversal agent when profound block was present or wait for some spontaneous recovery before antagonizing the block. This study has been conducted to evaluate the reversal effects of neostigmine with divided doses in the rabbits after pancuronium when profound relaxation(PTC=O) or the first twitch of TOF stimulation was appeared (TOF,T1) was confirmed. METHODS: Rabbits(n=60) were randomly allocated to 5 groups. After pancuronium 0.2 mg/kg intravenously, spontaneous recovery was evaluated in group 1. When the profound relaxation(PTC=O) was confirmed at 5 min. after pancuronium, neostigmine 50 ug/kg with atropine 20 ug/kg were injected in group 2. At that time, neostigmine 10 ug/kg with atropine 4 ug/kg were injected and after 3 min. neostigmine 40 ug/kg with atropine 16 ug/kg were injected in group 3. When TOF, Tl was confirmed, neostigmine 50 ug/kg with atropine 20 ug/kg were injected in group 4. At that time, neostigmine and atropine were injected in group 5 as the same way of group 3. RESULTS: The mean time from injection of pancuronium to 95% recovery was 98.9 min. in group 1, 60.3 min. in group 2, 50.9 min. in group 3, 71.0 min. in group 4 and 67.1 min. in group 5. The recovery index was significantly reduced when neostigmine was injected at TOF,T1(p<0.05). The recovery time after neostigmine with divided doses was reduced, but there was no significant difference. CONCLUSIONS: The results of present study suggested that total recovery time was reduced when neostigmine was injected earlier with divided doses than single dose unrelated to profound relaxation.
Atropine
;
Muscle Relaxation*
;
Neostigmine*
;
Pancuronium
;
Rabbits*
;
Relaxation
5.The Role K+ channel and the Effect of K+ channel Opener in the Relaxation of Vaginal Smooth Muscle.
Hong Seok PARK ; Heung Jae PARK ; Du Geon MOON ; Je Jong KIM ; Sung Kun KOH
Korean Journal of Urology 2000;41(8):968-975
No abstract available.
Muscle, Smooth*
;
Relaxation*
6.Study on the effects of traditional relaxation training on some neural communicative substances and cortex of suprarenal hormones
Journal of Vietnamese Medicine 2004;302(9):25-29
Research was done in 150 subjects aged from 20 to 74 years old, dividing into 3 groups: normal adult subject, aged patients with hypertension and aged patients with neuralsthenia.
Concentrations of catecholamin, acetylcholin and cortisol were measured in 2 different times: before and 8 weeks after practising traditional techniques of relaxation. The results showed that: tratitional techniques exercising reduced serum level of catecholamin, acetylchoin cortisol after 8 weeks exercising continously
Relaxation
;
Medicine, Traditional
;
Hormones
7.Concept Analysis of Comfort.
Journal of Korean Academy of Adult Nursing 1999;11(1):169-178
The concept of comfort has been regarded as a core concept of nursing and it has been frequently used as one of main goals of nursing care. Promoting comfort has been a very important objective in clinical nursing practice. There have been some ambiguities in defining the concept of 'comfort" among nursing scholars. Therefore it was necessary to analyse the concept of comfort for clearer definition to be able to share among scholars. This study is an attempt to analyse concept of comfort and to do it according to a series of concept development processes described by Walker and Avant. Based on the results of the study, the attributes of scope, precedence and consequence of comfort were identified : 1. Attributes 1) stability 2) directionality 3) equilibrium 4) firmness 2. Scope 1) physical 2) social 3) emotional 4) spiritua~ 3. Precedence and Consequence 1) precedence (1) instability (2) unsatisfied needs 2) consequence (1) physical & psychological relaxation (2) enhancement of self-worth (3) enhancement of self-efficacy (4) satisfied needs.
Nursing
;
Nursing Care
;
Relaxation
8.Assessment of Early Diastolic Left Ventricular Relaxation in Patients with Valvular Regurgitation(with Reference to Incremental Delta Elastance).
Chong Hun PARK ; Young Woo LEE
Korean Circulation Journal 1984;14(1):7-15
Early diastolic left ventricular relaxation was determined in 20 patients by combined echopressure measurement. 7 normal control cases and 13 cases with valvular regurgitation were studied with reference to incremental delta elastance. The hemodynamic and echocardiographic data were analysed during the phase of decreasing left ventricular elastance (that is, when pressure is decreasing while volume is increasing). Starting from a fixed level of wall stress (40 kdyne/cm2), we determined Incremental Delta Elastance(ratio big up tri, Delta p/big up tri, Delta V) by a constant increase in LV volume(eg. 10 ml/M2 or 20 ml/M2). We named Incremental Delta Elastance at 10 ml/M2 and 20 ml/M2 of LV volume increase as d-E 10 and d-E 20 respectively. In valvular regurgitation, incremental delta elastances were statistically different from those of normal subjects(p<0.01). d-E10 was -1.67+/-0.69(versus -3.38+/-1.75 in normal subjects) mmHgm2/ml and d-E20 was -0.98+/-0.39(versus -1.69+/-0.84 in normal subjects) mmHgm2/ml. d-E 10 and d-E20 were compared with ejection phase indices(ejection fraction, meanVcf) in whole group(n=20). There was significant correlation between d-E and ejection fraction(d-E10 : r=-0.47, d-E20:r=-0.50) p<0.05. There was significant correlation between d-E and meanVcf(d-E10: r=0.53, d-E20: r=-0.57) p<0.05. d-E10 and d-E20 were compared with volume indices(end-diastolic volume index and end-systolic volume index) but no significant correlation was found. Because we evaluated that inotropic state or afterload would influence incremental delta elastance, further study, especially with reference to endsystolic volume index may be needed. The absolute values between d-E10 and d-E20 were different but they were simliar in property. We concluded that incremental delta elastance(d-E10 or d-E20) could be used as a useful index of early diastolic relaxation in chronic valvular regurgitation.
Echocardiography
;
Hemodynamics
;
Humans
;
Relaxation*
9.T1-, T2-weighted, and FLAIR Imaging: Clinical Application.
Journal of the Korean Society of Magnetic Resonance in Medicine 2009;13(1):9-14
T1-, and T2-weighted imagings and FLAIR (fluid attenuated inversion recovery) imaging are fundamental imaging methods in the brain. T1-weighted imaging is a spin-echo sequence with short TR and short TE and produces the tissue contrast by different T1 relaxation times. In other words, short TR maximizes the difference of the longituidinal magnetization recovery between the tissues. T2-weighted imaging is a spin-echo sequence with long TR and long TE and produces the tissue contrast by different T2 relaxation times. Long TE maximizes the difference of the transverse magnetization decay between the tissues. FLAIR is an inversion recovery sequence using 180 degree inversion pulse. 2500 msec of inversion time is applied to suppress the CSF signal.
Brain
;
Magnets
;
Relaxation
10.The Biomechanical Responses of Intervertebral Disc due to Degenerative Change in Porcine Lumbar Spine.
Chul PARK ; Jung Woog SHIN ; Chan Hwan KIM ; Jin Woo LEE ; Sung Hwan MUN ; Ki Dong PARK ; Young Jick KIM ; Su A PARK
Journal of Korean Orthopaedic Research Society 2003;6(1):106-116
PURPOSE: The biomechanical responses of degenerative porcine intervertebral disc were compared with those MATERIALS AND METHODS: Two groups were set; Group A (44.0+/-2.8 months old, female) and Group B (6.2 +/-1.3 months old, female). Histological (H&E stain) observations were carried out to see the degeneration for both groups. Then biomechanical responses were investigated by measuring height changes in disc, intradiscal pressure values and relaxation time for each specimen under axial compressive loads. RESULTS: Degenerative changes were confirmed through H&E staining in Group A. The ratios of the nucleus pulposus area to total area were 14.7+/-4.5% and 29.2+/-6.0% in Group A and B, respectively (p=0.000). The decrease rates in disc height were 12.1+/-3.3% and 21.6+/-7.6%, in Group A and B, respectively under the axial compression of 740 N (p=0.000). No significant difference in intradiscal pressure measured in anterior zone between-groups except at axial load of 740N (p> 0.05). However, significant difference in pressure was found in posterolateral zone when the load was 542 N and higher (542 N: p=0.015, 740 N: p=0.010). The average relaxation time for Group A was significantly longer than that for Group B at 740N, i.e., at maximum load (anterior: p=0.010, posterolateral: p=0.014). CONCLUSION: Different biomechanical responses in degenerative disc were confirmed. They are 1) less flexible, 2) slower in energy relaxation under axial loading, and 3) larger portion of the external load were taken up at posterior part of annulus fibrous, especially in degenerative disc.
Intervertebral Disc*
;
Relaxation
;
Spine*