1.The Influence of Fixation Rigidity on Intervertebral Joints - An Experimental Comparison between a Rigid and a Flexible System.
Won Joong KIM ; Sang Ho LEE ; Song Woo SHIN ; Charles H RIVARD ; Christine COILLARD ; Souad RHALMI
Journal of Korean Neurosurgical Society 2005;37(5):364-369
OBJECTIVE: Spinal instrumentation without fusion often fails due to biological failure of intervertebral joints (spontaneous fusion, degeneration, etc). The purpose of this study is to investigate the influence of fixation rigidity on viability of intervertebral joints. METHODS: Twenty pigs in growing period were subjected to posterior segmental fixation. Twelve were fixed with a rigid fixation system(RF) while eight were fixed with a flexible unconstrained implant(FF). At the time of the surgery, a scoliosis was created to monitor fixation adequacy. The pigs were subjected to periodic radiological examinations and 12pigs (six in RF, six in FF) were euthanized at 12-18months postoperatively for analysis. RESULTS: The initial scoliotic curve was reduced from 31+/-5degrees to 27+/-8degrees in RF group (p=0.37) and from 19+/-4degrees to 17+/-5degrees in FF group (p=0.21). Although severe disc degeneration and spontaneous fusion of facet joints were observed in RF group, disc heights of FF group were well maintained without major signs of degeneration. CONCLUSION: The viability of the intervertebral joints depends on motion spinal fixation. Systems allowing intervertebral micromotion may preserve the viability of intervertebral discs and the facet joint articular cartilages while maintaining a reasonably stable fixation.
Cartilage, Articular
;
Intervertebral Disc
;
Intervertebral Disc Degeneration
;
Joints*
;
Scoliosis
;
Swine
;
Zygapophyseal Joint
2.Beef from the United States: Is It Safe?.
Keun Soo KIM ; Taesu KIM ; Hanbyul CHOI ; Christine AHN ; Christopher C LEE
Journal of Korean Medical Science 2016;31(7):1009-1010
No abstract available.
Animals
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Cattle
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Encephalopathy, Bovine Spongiform/epidemiology
;
Meat/*analysis
;
United States
3.Effectiveness of Fluid and Caffeine Modifications on Symptoms in Adults With Overactive Bladder: A Systematic Review
Jeongok PARK ; Hyojin LEE ; Youngkyung KIM ; Christine NORTON ; Sue WOODWARD ; Sejeong LEE
International Neurourology Journal 2023;27(1):23-35
Overactive bladder (OAB) is prevalent in men and women and negatively impacts physical and psychological health. Fluid and caffeine intake modifications, which are lifestyle modification interventions, are simple methods to manage OAB. However, studies that synthesized both interventions and found scientific evidence are scarce. This review aimed to synthesize scientific evidence on whether fluid and caffeine intake modifications are effective for OAB symptoms. PubMed, CINAHL (Cumulative Index for Nursing and Allied Health Literature), Embase, Scopus, the Cochrane Library, KoreaMed, and RISS (Research Information Sharing Service) were used to search for studies and 8 studies were included. The Cochrane risk of bias tool (RoB 2.0) and ROBINS-I (Risk Of Bias In Non-randomized Studies - of Interventions) were used to assess the quality of selected studies. Due to the heterogeneous outcome variables, a meta-analysis was not conducted. Among the 8 included, 7 studies were randomized controlled trials and one was a quasi-experimental study. Four studies assessed urgency. Caffeine reduction was statistically effective for urgency symptoms, but increasing fluid intake was not. Frequency was assessed in 5 studies, which showed decreasing caffeine and fluid intake was effective in treating the symptoms. Urinary incontinence episodes were assessed in 6 studies, and nocturia in 2. Restricting caffeine intake was effective in treating these 2 symptoms, but restricting both caffeine and fluid intake was not. Quality of life (QoL) was examined in 5 studies, and modifying fluid and caffeine intake significantly improved QoL in 2. Although there were limited studies, our review provides scientific evidence that fluid and caffeine intake modification effectively manages OAB symptoms. Further research should examine acceptability and sustainability of interventions in the long-term and enable meta-analysis.
4.The Effect of Segmental Pedicle Screw Instrumentation on Actively Growing Spine: A Long-term Experimental Study.
Won Joong KIM ; Sang Ho LEE ; Song Woo SHIN ; Charles H RIVARD ; Christine COILLARD ; Souad RHALMI
Journal of Korean Neurosurgical Society 2004;35(5):502-506
OBJECTIVE: Pedicle screw is gaining popularity in pediatric deformities. However, biological response of actively growing spine to rigid pedicle screw fixation remains unclear. The objective of this study is to determine the biological response of growing spine to rigid segmental fixation. METHODS: Twelve mini pigs in actively growing period were subjected to posterior segmental screw -rod instrumentation spanning nine levels and creation of experimental scoliosis. There was no attempt of posterior arthrodesis. The pigs were subjected to periodic radiological examinations and were euthanized at 18 months for analysis. RESULTS: There was no significant fixation failure despite conspicuous growth of the animals. Initial scoliosis of 31+/-5degrees was reduced to 27+/-8degrees at 18 months, but there was no statistical significance (p=0.37). Though there was no change in length of the implant construct, the vertebrae within the instrumented section showed mean longitudinal growth of 6+/-3 mm (p=0.000). The growth occurred at expense of the disc spaces that progressively narrowed with time. On necropsy, the instrumented region was completely fused posteriorly with crossing of the osseous traberculae across the former facet joints. Intervertebral discs were severely atrophic in all the discs with occasional spontaneous fusion. CONCLUSION: Even in the actively growing spine, the force of growth does not overcome the fixation offered by segmental pedicle screws. Longitudinal growth occurs at the expense of the joint spaces and leads to spontaneous intervertebral fusion. Our results may explain the favorable outcomes in pedicle fixations in pediatric population, showing little implant failure or nonunion.
Animals
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Arthrodesis
;
Congenital Abnormalities
;
Intervertebral Disc
;
Joints
;
Scoliosis
;
Spine*
;
Swine
;
Zygapophyseal Joint
5.Characterization of Vitamin B12 Supplementation and Correlation with Clinical Outcomes in a Large Longitudinal Study of Early Parkinson's Disease
Cameron DIETIKER ; Soeun KIM ; Yunxi ZHANG ; Chadwick W CHRISTINE ;
Journal of Movement Disorders 2019;12(2):91-96
OBJECTIVE: In Parkinson's disease (PD), vitamin B12 levels are lower, and comorbid B12 deficiency has been associated with the development of neuropathy and early gait instability. Because little is known about B12 supplement use in PD, we sought to evaluate its use in a large PD cohort and, as an exploratory analysis, to determine whether baseline characteristics or disease progression differed according to B12 supplementation. METHODS: We utilized data collected as part of the National Institutes of Health Exploratory Trials in PD (NET-PD) Long-term Study (LS-1), a longitudinal study of 1,741 participants. We stratified subjects into 4 groups according to daily supplement use: no B12, multivitamin (MVI) containing < 100 μg B12, B12 ≥ 100 μg, and MVI + B12 ≥ 100 μg. Clinical outcomes were assessed at 3 years for each group using the Unified Parkinson's Disease Rating Scale (UPDRS), its subscores, and selected individual questions. RESULTS: Of the 1,147 participants who completed the 3-year visit, 41% took an MVI, 2% took B12, 3% took MVI + B12, and 54% reported taking no supplements. At 3 years, no significant differences in clinical outcomes were observed. However, there was a trend toward lower hazard ratios for developing sensory symptoms (UPDRS Item 17) in the MVI (p = 0.08) and B12 + MVI (p = 0.08) groups compared to that in the no supplement group. CONCLUSION: These results show that supplementation with vitamin B12 ≥ 100 μg is uncommon in early PD. The finding of a trend toward a lower hazard ratio for the development of sensory symptoms in those taking an MVI or B12 + MVI warrants further study.
Cohort Studies
;
Disease Progression
;
Gait
;
Longitudinal Studies
;
National Institutes of Health (U.S.)
;
Neuroprotection
;
Parkinson Disease
;
Vitamin B 12
;
Vitamins
6.Anti-adipogenic Pregnane Steroid from a Hydractinia-associated Fungus, Cladosporium sphaerospermum SW67
Seoung Rak LEE ; Heesun KANG ; Min Jeong YOO ; Sang Ah YI ; Christine BEEMELMANNS ; Jaecheol LEE ; Ki Hyun KIM
Natural Product Sciences 2020;26(3):230-235
A pregnane steroid, 3α-hydroxy-pregn-7-ene-6,20-dione (1), was isolated from a Hydractinia-associated Cladosporium sphaerospermum SW67 by repetitive column chromatographic separation and highperformance liquid chromatography (HPLC) purification. The planar structure of 1 was elucidated from the analysis of the spectroscopic data (1D and 2D NMR spectra) and LC-MS data. The absolute configuration of 1 was determined by interpretation of ROESY spectrum of 1, together with the comparison of reported spectroscopic values in previous studies. To the best of our knowledge, this is the first report of the identification of the pregnane scaffold from C. sphaerospermum, a natural source. Compound 1 was evaluated for its effects on lipid metabolism and adipogenesis during adipocyte maturation and showed that compound 1 substantially inhibited lipid accumulation compared to the control. Consistently, the expression of the adipocyte marker gene (Adipsin) was reduced upon incubation with 1. Further, we evaluated the effects of 1 on lipid metabolism by measuring the transcription of lipolytic and lipogenic genes. The expression of the lipolytic gene ATGL was significantly elevated upon exposure to 1 during adipogenesis, whereas the expression of lipogenic genes FASN and SREBP1 was significantly reduced upon treatment with 1. Thus, our findings provide experimental evidence that the steroid derived from Hydractinia-associated C. sphaerospermum SW67 is a potential therapeutic agent for obesity.
7.A Novel Heterozygous Missense Variant (c.667G>T;p.Gly223Cys) in USH1C That Interferes With Cadherin-Related 23 and Harmonin Interaction Causes Autosomal Dominant Nonsyndromic Hearing Loss
Ju Sun SONG ; Amel BAHLOUL ; Christine PETIT ; Sang Jin KIM ; Il Joon MOON ; Jinhyuk LEE ; Change Seok KI
Annals of Laboratory Medicine 2020;40(3):224-231
BACKGROUND:
Pathogenic variants of USH1C, encoding a PDZ-domain-containing protein called harmonin, have been known to cause autosomal recessive syndromic or nonsyndromic hearing loss (NSHL). We identified a causative gene in a large Korean family with NSHL showing a typical pattern of autosomal dominant (AD) inheritance.
METHODS:
Exome sequencing was performed for five affected and three unaffected individuals in this family. Following identification of a candidate gene variant, segregation analysis and functional studies, including circular dichroism and biolayer interferometry experiments, were performed.
RESULTS:
A novel USH1C heterozygous missense variant (c.667G>T;p.Gly223Cys) was shown to segregate with the NSHL phenotype in this family. This variant affects an amino acid residue located in the highly conserved carboxylate-binding loop of the harmonin PDZ2 domain and is predicted to disturb the interaction with cadherin-related 23 (cdh23). The affinity of the variant PDZ2 domain for a biotinylated synthetic peptide containing the PDZ-binding motif of cdh23 was approximately 16-fold lower than that of the wild-type PDZ2 domain and that this inaccessibility of the binding site was caused by a conformational change in the variant PDZ2 domain.
CONCLUSIONS
A heterozygous variant of USH1C that interferes with the interaction between cdh23 and harmonin causes novel AD-NSHL.
8.Microvascular reactivity as a predictor of major adverse events in patients with on-pump cardiac surgery
Ah-Reum CHO ; Hyeon-Jeong LEE ; Jeong-Min HONG ; Christine KANG ; Hyae-Jin KIM ; Eun-Jung KIM ; Min Su KIM ; Soeun JEON ; Hyewon HWANG
Korean Journal of Anesthesiology 2022;75(4):338-349
Background:
Microcirculatory disturbances are typically most severe during cardiopulmonary bypass (CPB), which occurs during cardiac surgeries. If microvascular reactivity compensates for microcirculatory disturbances during CPB, tissue hypoxemia can be minimized. The primary aim of this study was to assess whether microvascular reactivity during CPB could predict major adverse events (MAE) after cardiac surgery.
Methods:
This prospective observational study included 115 patients who underwent elective on-pump cardiac surgeries. A vascular occlusion test (VOT) with near-infrared spectroscopy was performed five times for each patient: before the induction of general anesthesia, 30 min after the induction of general anesthesia, 30 min after applying CPB, 10 min after protamine injection, and post-sternal closure. The postoperative MAE was recorded. The area under the receiver operating characteristic (AUROC) curve analysis was performed for the prediction of MAE using the recovery slope.
Results:
Of the 109 patients, MAE occurred in 32 (29.4%). The AUROC curve for the recovery slope during CPB was 0.701 (P < 0.001; 95% CI [0.606, 0.785]). If the recovery slope during CPB was < 1.08%/s, MAE were predicted with a sensitivity of 62.5% and specificity of 72.7%.
Conclusions
Our study demonstrated that the recovery slope of the VOT during CPB could predict MAE after cardiac surgery. These results support the idea that disturbances in microcirculation induced by CPB can predict the development of poor clinical outcomes, thereby demonstrating the potential role of microvascular reactivity as an early predictor of MAE after cardiac surgery.
9.The agonistic action of URO-K10 on Kv7.4 and 7.5 channels is attenuated by co-expression of KCNE4 ancillary subunit
Jung Eun LEE ; Christine Haewon PARK ; Hana KANG ; Juyeon KO ; Suhan CHO ; JooHan WOO ; Mee Ree CHAE ; Sung Won LEE ; Sung Joon KIM ; Jinsung KIM ; Insuk SO
The Korean Journal of Physiology and Pharmacology 2020;24(6):503-516
KCNQ family constitutes slowly-activating potassium channels among voltage-gated potassium channel superfamily. Recent studies suggested that KCNQ4 and 5 channels are abundantly expressed in smooth muscle cells, especially in lower urinary tract including corpus cavernosum and that both channels can exert membrane stabilizing effect in the tissues. In this article, we examined the electrophysiological characteristics of overexpressed KCNQ4, 5 channels in HEK293 cells with recently developed KCNQ-specific agonist. With submicromolar EC50 , the drug not only increased the open probability of KCNQ4 channel but also increased slope conductance of the channel. The overall effect of the drug in whole-cell configuration was to increase maximal whole-cell conductance, to prolongate the activation process, and left-shift of the activation curve. The agonistic action of the drug, however, was highly attenuated by the co-expression of one of the βancillary subunits of KCNQ family, KCNE4. Strong in vitro interactions between KCNQ4, 5 and KCNE4 were found through Foster Resonance Energy Transfer and co-immunoprecipitation. Although the expression levels of both KCNQ4 and KCNE4 are high in mesenteric arterial smooth muscle cells, we found that 1 μM of the agonist was sufficient to almost completely relax phenylephrine-induced contraction of the muscle strip. Significant expression of KCNQ4 and KCNE4 in corpus cavernosum together with high tonic contractility of the tissue grants highly promising relaxational effect of the KCNQspecific agonist in the tissue.
10.The agonistic action of URO-K10 on Kv7.4 and 7.5 channels is attenuated by co-expression of KCNE4 ancillary subunit
Jung Eun LEE ; Christine Haewon PARK ; Hana KANG ; Juyeon KO ; Suhan CHO ; JooHan WOO ; Mee Ree CHAE ; Sung Won LEE ; Sung Joon KIM ; Jinsung KIM ; Insuk SO
The Korean Journal of Physiology and Pharmacology 2020;24(6):503-516
KCNQ family constitutes slowly-activating potassium channels among voltage-gated potassium channel superfamily. Recent studies suggested that KCNQ4 and 5 channels are abundantly expressed in smooth muscle cells, especially in lower urinary tract including corpus cavernosum and that both channels can exert membrane stabilizing effect in the tissues. In this article, we examined the electrophysiological characteristics of overexpressed KCNQ4, 5 channels in HEK293 cells with recently developed KCNQ-specific agonist. With submicromolar EC50 , the drug not only increased the open probability of KCNQ4 channel but also increased slope conductance of the channel. The overall effect of the drug in whole-cell configuration was to increase maximal whole-cell conductance, to prolongate the activation process, and left-shift of the activation curve. The agonistic action of the drug, however, was highly attenuated by the co-expression of one of the βancillary subunits of KCNQ family, KCNE4. Strong in vitro interactions between KCNQ4, 5 and KCNE4 were found through Foster Resonance Energy Transfer and co-immunoprecipitation. Although the expression levels of both KCNQ4 and KCNE4 are high in mesenteric arterial smooth muscle cells, we found that 1 μM of the agonist was sufficient to almost completely relax phenylephrine-induced contraction of the muscle strip. Significant expression of KCNQ4 and KCNE4 in corpus cavernosum together with high tonic contractility of the tissue grants highly promising relaxational effect of the KCNQspecific agonist in the tissue.