1.Surgical Treatment of Patellar Instability in Children and Adolescents.
Jung Woo LEE ; Yongjun LEE ; Kun Bo PARK
The Journal of the Korean Orthopaedic Association 2018;53(3):201-209
Patellar instability in children and adolescents is caused by abnormalities of various knee structures. Instability of the patellofemoral joint can manifest as an acute dislocation, recurrent dislocation, habitual dislocation, and congenital dislocation. Patellar instability is associated with abnormalities in the anatomical structures around the knee, and a comprehensive analysis of the cause should be undertaken. Surgery can be performed to reconstruct any abnormal musculo-skeletal alignment. Considerable progress has been made in the treatment of patellar instability in recent years, and surgical methods include lateral release, soft tissue realignment procedure, transfer of the autologous tendon, trochleaplasty, and reconstruction of the medial patellofemoral ligament.
Adolescent*
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Child*
;
Dislocations
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Humans
;
Joint Instability
;
Knee
;
Ligaments
;
Patella
;
Patellofemoral Joint
;
Tendons
2.Cyclic Stretching Induces Maturation of Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes through NuclearMechanotransduction
Myeongjin SONG ; Yongjun JANG ; Seung-Jong KIM ; Yongdoo PARK
Tissue Engineering and Regenerative Medicine 2022;19(4):781-792
BACKGROUND:
During cardiogenesis, cardiac cells receive various stimuli, such as biomechanical and chemical cues, from the surrounding microenvironment, and these signals induce the maturation of heart cells. Mechanical force, especially tensile force in the heart, is one of the key stimuli that induce cardiomyocyte (CM) maturation through mechanotransduction, a process through which physical cues are transformed into biological responses. However, the effects and mechanisms of tensile force on cell maturation are poorly studied.
METHODS:
In this study, we developed a cyclic stretch system that mimics the mechanical environment of the heart by loading tensile force to human-induced pluripotent stem cell (hiPSC)-derived CMs. hiPSC-CMs cultured with the cyclic stretch system analyzed morphological change, immunofluorescent staining, expression of maturation markers in mRNA, and beating properties compared to static cultures.
RESULTS:
hiPSC-CMs cultured with the cyclic stretch system showed increased cell alignment, sarcomere length and expression of maturation markers in mRNA, such as TNNI3, MYL2 and TTN, compared to static cultures. Especially, the expression of genes related to nuclear mechanotransduction, such as Yap1, Lamin A/C, plectin, and desmin, was increased in the cyclically stretched hiPSC-CMs. Furthermore, the volume of the nucleus was increased by as much as 120% in the cyclic stretch group.
CONCLUSION
These results revealed that nuclear mechanotransduction induced by tensile force is involved in CM maturation. Together, these findings provide novel evidence suggesting that nuclear mechanotransduction induced by tensile force is involved in the regulation of cardiac maturation.
3.Nail DNA and Possible Biomarkers: A Pilot Study.
Joshua PARK ; Debbie LIANG ; Jung Woo KIM ; Yongjun LUO ; Taesheng HUANG ; Soo Young KIM ; Seong Sil CHANG
Journal of Preventive Medicine and Public Health 2012;45(4):235-243
OBJECTIVES: Nail has been a substitute DNA source for genotyping. To investigate the integrity and consistency of nail DNA amplification for biomarker study, nail clippings from 12 subjects were collected at monthly intervals. The possibility of longer amplification and existence of GAPDH RNA/protein, were also investigated with three nail samples. METHODS: Three primer sets were designed for quantitative amplification of nuclear and mitochondrial genes and analysis of their consistency. The mean threshold cycles in amplification of the target genes were compared to test the consistency of polymerase chain reaction (PCR) performance among individual factors including age groups, sex, family, the nail source, and by the size of the amplification segments. RESULTS: The amplification of the target genes from nail DNA showed similar integrity and consistency between the nail sources, and among the serial collections. However, nail DNA from those in their forties showed earlier threshold cycles in amplification than those in their teens or seventies. Mitochondrial DNA (mtDNA) showed better DNA integrity and consistency in amplification of all three targets than did nuclear DNA (nucDNA). Over 9 kb of mtDNA was successfully amplified, and nested quantitative PCR showed reliable copy numbers (%) between the two loci. Reverse transcription PCR for mRNA and immunoblotting for GAPDH protein successfully reflected their corresponding amounts. Regarding the existence of RNA and protein in nails, more effective extraction and detection methods need to be set up to validate the feasibility in biomarker study. CONCLUSIONS: Nail DNA might be a feasible intra-individual monitoring biomarker. Considering integrity and consistency in target amplification, mtDNA would be a better target for biomarker research than nucDNA.
Adult
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Age Factors
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Aged
;
Biological Markers/analysis
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Child
;
DNA/*analysis/isolation & purification
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DNA Primers
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DNA, Mitochondrial/analysis
;
Feasibility Studies
;
Female
;
Gene Amplification
;
Humans
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Male
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Middle Aged
;
Nails/*chemistry
;
Pilot Projects
4.Performance Assessment of Advansure(TM) MDR-TB Genoblot Assay Kit for Anti-tuberculosis Drug Susceptibility Test.
Sang Bong HAN ; Yongjun JO ; Jin Kyung YU ; Yonggoo KIM ; Yeon Joon PARK
Laboratory Medicine Online 2012;2(1):34-40
BACKGROUND: Because of the long time required for conventional drug susceptibility test (DST) for rifampin and isoniazid, development of rapid DSTs is necessary. Recently, the AdvanSure(TM) MDR-TB GenoBlot Assay kit (LG Life Science, Korea), using reverse hybridization line blot assay, was developed. We compared this kit with Genotype(R) MTBDRplus (HAIN Lifescience, Germany) and conventional DST. METHODS: Of the DNAs preserved after performing DST by using Genotype(R), we selected 144 samples having conventional DST results. The experiments with both the kits were performed according to the manufacturers' instructions. For the samples for which discrepant results were obtained, sequencing was performed if the DNA was available. Conventional DST was performed at the Korean Institute of Tuberculosis by using the absolute concentration method. RESULTS: For rifampin, the findings obtained using both the kits were the same with concordance rates of 98.6% (142/144) compared to conventional DST. Of the 2 discrepant findings, one was very major error and the other was major error. For isoniazid, compared to conventional DST, concordance rates of AdvanSure(TM) and Genotype(R) were 95.8%(138/144) and 95.1%(137/144) respectively. Of the 6 discrepant findings between conventional method and Advansure(TM), 5 were very major error and one was major error. All the 7 discrepant findings between conventional method and Genotype(R) were very major error. CONCLUSIONS: The findings obtained using AdvanSure(TM) showed high concordance with those obtained using Genotype(R) and conventional DST. This kit has a higher rate of detection of isoniazid resistance because it includes probes for an additional target (ahpC).
Biological Science Disciplines
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Chimera
;
DNA
;
Isoniazid
;
Rifampin
;
Tuberculosis
5.Evaluation of HbA1c Levels Via the Latex Immunoturbidimetric Method by Using Chemistry Autoanalyzer.
Yongjun JO ; So young LEE ; Hae il PARK ; YeongSic KIM ; Jehoon LEE ; Yonggoo KIM ; Kyungja HAN
Laboratory Medicine Online 2012;2(1):10-14
BACKGROUND: Measurement of HbA1c levels is widely used to diagnose diabetes mellitus and to evaluate and monitor plasma-glucose concentrations over 6-8 weeks. In this study, we evaluated the diagnostic performance of the newly developed latex immunoturbidimetric method by using Autolab HbA1c. METHODS: We analyzed and compared the diagnostic performance of Autolab HbA1c with that of Toshiba 200FR between April 2009 and July 2009. According to guidelines (EP5-A2, EP6-P, EP9-A2) of the clinical and laboratory standards institute (CLSI), we compared linearity, precision and correlation of Autolab HbA1c with those of G7 (Tosoh Corp., Kyoto, Japan) by using high-performance liquid chromatography (HPLC) method. RESULTS: Data obtained using Autolab HbA1c showed good linearity in mixtures of samples with low (3.1%) and high (15.1%) levels of HbA1c (r2 = 0.9997). In the analysis of within-run precision of the samples with HbA1c levels of 5.1% and 12.1%, the SDs were 0.04 and 0.06 and covariances of these samples were 0.8% and 0.5%, respectively. In the Deming regression model, the regression equation was as follows: Autolab HbA1c = 1.0859xTosoh HPLC-0.6957. CONCLUSIONS: In this study, Autolab HbA1c method showed better performance characteristics than Tosoh G7 did. In reference review, there was no interference of variant hemoglobin. The data acquisition time of Autolab HbA1c was lower than that of Tosoh G7. The advantages of Autolab HbA1c are that it can be used as an autoanlyzer in routine chemical analysis, it does not require pre-analytical treatment, and the samples are automatically treated with distilled water for hemolysis.
Chromatography, High Pressure Liquid
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Chromatography, Liquid
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Diabetes Mellitus
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Hemoglobins
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Hemolysis
;
Latex
;
Organothiophosphorus Compounds
;
Water
6.An Engineering View on Megatrends in Radiology: Digitization to Quantitative Tools of Medicine.
Namkug KIM ; Jaesoon CHOI ; Jaeyoun YI ; Seungwook CHOI ; Seyoun PARK ; Yongjun CHANG ; Joon Beom SEO
Korean Journal of Radiology 2013;14(2):139-153
Within six months of the discovery of X-ray in 1895, the technology was used to scan the interior of the human body, paving the way for many innovations in the field of medicine, including an ultrasound device in 1950, a CT scanner in 1972, and MRI in 1980. More recent decades have witnessed developments such as digital imaging using a picture archiving and communication system, computer-aided detection/diagnosis, organ-specific workstations, and molecular, functional, and quantitative imaging. One of the latest technical breakthrough in the field of radiology has been imaging genomics and robotic interventions for biopsy and theragnosis. This review provides an engineering perspective on these developments and several other megatrends in radiology.
Biological Markers/analysis
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Biomedical Engineering
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Diagnosis, Computer-Assisted/*trends
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Diagnostic Imaging/*trends
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Equipment Design
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Genomics
;
Humans
;
Image Processing, Computer-Assisted/*trends
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Radiology Information Systems/*trends
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Robotics
;
Systems Integration
;
User-Computer Interface
7.Swallowing Difficulty due to Hypothyroid Myopathy: A Case Report.
Donggyun SOHN ; Geun Young PARK ; Hyunjung KOO ; YongJun JANG ; Sun IM
Journal of the Korean Dysphagia Society 2018;8(2):126-131
Musculoskeletal symptoms, such as muscle weakness, stiffness and pain, are observed frequently in patients with hypothyroidism. In theory, hypothyroidism can cause weakness of the swallowing muscles, but dysphagia associated with hypothyroidism-associated myopathy has not been reported. The present case involved a 51-year-old man who experienced acute onset of severe dysphagia with aspiration pneumonia. A video fluoroscopic swallowing study and fiberoscopic endoscopic evaluation of swallowing revealed pharyngo-laryngeal function impairment. With a prior history of subclinical hypothyroidism and clinical symptoms such as proximal limb weakness, further evaluation involving a hormonal study, electrodiagnostic study, and histopathology assessment revealed myopathy. Hormone replacement therapy was started and the patient recovered within three weeks of treatment and was taking a regular diet. In conclusion, this study suggests that it is necessary to consider further evaluations to determine if hypothyroid myopathy is involved in the case of unknown origin dysphagia accompanied by hypothyroid myopathy.
Deglutition Disorders
;
Deglutition*
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Diet
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Extremities
;
Hormone Replacement Therapy
;
Humans
;
Hypothyroidism
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Middle Aged
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Muscle Weakness
;
Muscles
;
Muscular Diseases*
;
Pneumonia, Aspiration
8.Persicaria senticosa Ameliorates Imiquimod-induced Psoriasis-like Skin Lesions in Mice via Suppression of IL-6/STAT3 Expression and Proliferation of Keratinocytes
Sangmi JUNG ; Jeong-Ran PARK ; Moonjin RA ; Young Han KIM ; Ji Hoon YU ; Yongjun LEE
Natural Product Sciences 2020;26(2):136-143
Psoriasis is one of the most common inflammatory skin disorders, with a global prevalence of 2% – 3%. It is an autoimmune skin disorder characterized by excessive generation of plaques on the skin with typical long-lasting red, itchy, and scaly lesions. In this study, we aimed to elucidate the anti-psoriatic effect of the methanolic extract of Persicaria senticosa (PS), a bioactive edible plant extract used in traditional medicine, using a mouse model of imiquimod (IMQ)-induced psoriasis. The daily topical application of IMQ could induce human psoriasis-like lesion. The extract ameliorated IMQ-induced psoriasis. Furthermore, hematoxylin and eosin staining and the Psoriasis Area and Severity Index (PASI) scores indicated that topical application of PS led to an improvement in erythema, scaling, and thickness scores of the mouse dorsal skin and a considerable decrease in the epidermal thickness of the ear and dorsal skin in the IMQ-induced psoriatic mouse model. We also studied the effect of PS on the proliferation of keratinocytes using HaCaT cells. The extract inhibited cell proliferation and IL-6 and pSTAT3 expression induced by M5 cocktail (comprising interleukin [IL]-1α, IL-17A, IL-22, oncostatin M, and tumor necrosis factor-α) in HaCaT cells. Thus, PS might serve as a potential therapeutic agent for the treatment of psoriasis.
9.Number Processing Error as a Clinical Manifestation of Hemispatial Neglect Following Hypoxic Brain Injury:a Case Report
Yongjun JANG ; Eunji LEE ; Youngkook KIM ; Joo Hyun PARK
Brain & Neurorehabilitation 2020;13(3):e20-
Hemispatial neglect is a symptom where patients do not show response to stimuli on the contralesional side of their brain lesion. Although it is most common in the context of hemispheric stroke, several pathological processes including neurodegenerative disease, neoplasia, and trauma may cause this. Prevalence of hemispatial neglect is unknown and rarely reported among patients with hypoxic brain injury. Also, hemispatial neglect accompanying neglect dyslexia is rather hard to be recognized and symptoms involving numbers are exceptionally rare. We report a patient with hypoxic brain injury following cardiac arrest who showed signs of neglect dyslexia for numbers that provided a primary clue for the diagnosis of left hemispatial neglect. Early detection of different forms of cognitive dysfunction of hypoxic brain injury is highly essential in providing early neurorehabilitation for better prognosis.
10.Unusual Lower Back Pain on the Non-Articulated Side in Patient with Bertolotti’s Syndrome
Inah KIM ; Jong In LEE ; Yongjun JANG ; Hae-Yeon PARK
Clinical Pain 2021;20(1):49-52
Bertolotti’s syndrome (BS) refers to chronic low back pain (LBP) associated with lumbosacral transitional vertebrae (LSTV). Many studies suggest that the anomalous articulation alters biomechanics, resulting in discomfort on the ipsilateral side. Herein, we present an unusual case of BS presenting pain on the non-articulated side. A 46-year-old man visited our clinic with history of chronic LBP, refractory to treatment of analgesics, modalities and manual therapies. Electrodiagnostic studies showed no evidence of lumbosacral radiculopathy. Radiographies noted unilateral pseudoarticulation of L5∼S1 vertebrae, on the contralateral side of his pain. The pain improved dramatically after sacroiliac joint block and facet joint block with iliolumbar ligament infiltration on the non-articulated side. Clinicians should be cautious that the unaffected joint in BS may serve an important role in altered lumbopelvic biomechanism, since it might eventually lead to intractable chronic LBP when overlooked.