1.Intracisternal Administration of Voltage Dependent Calcium Channel Blockers Attenuates Orofacial Inflammatory Nociceptive Behavior in Rats.
Kyoung A WON ; Sang H PARK ; Bo K KIM ; Kyoung S BAEK ; Dong H YOON ; Dong K AHN
International Journal of Oral Biology 2011;36(2):43-50
Voltage dependent calcium channel (VDCC), one of the most important regulator of Ca2+ concentration in neuron, play an essential role in the central processing of nociceptive information. The present study investigated the antinociceptive effects of L, T or N type VDCC blockers on the formalin-induced orofacial inflammatory pain. Experiments were carried out on adult male Sprague-Dawley rats weighing 220-280 g. Anesthetized rats were individually fixed on a stereotaxic frame and a polyethylene (PE) tube was implanted for intracisternal injection. After 72 hours, 5% formalin (50 microL) was applied subcutaneously to the vibrissa pad and nociceptive scratching behavior was recorded for nine successive 5 min intervals. VDCC blockers were administered intracisternally 20 minutes prior to subcutaneous injection of formalin into the orofacial area. The intracisternal administration of 350 or 700 microg of verapamil, a blocker of L type VDCC, significantly decreased the number of scratches and duration in the behavioral responses produced by formalin injection. Intracisternal administration of 75 or 150 microg of mibefradil, a T type VDCC blocker, or 11 or 22 microg of cilnidipine, a N type VDCC blocker, also produced significant suppression of the number of scratches and duration of scratching in the first and second phase. Neither intracisternal administration of all VDCC blockers nor vehicle did not affect in motor dysfunction. The present results suggest that central VDCCs play an important role in orofacial nociceptive transmission and a targeted inhibition of the VDCCs is a potentially important treatment approach for inflammatory pain originating in the orofacial area.
Adult
;
Animals
;
Calcium
;
Calcium Channel Blockers
;
Calcium Channels
;
Calcium Channels, L-Type
;
Calcium Channels, N-Type
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Calcium Channels, T-Type
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Dihydropyridines
;
Facial Pain
;
Formaldehyde
;
Humans
;
Injections, Subcutaneous
;
Male
;
Mibefradil
;
Neurons
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Pain Measurement
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Polyethylene
;
Rats
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Rats, Sprague-Dawley
;
Verapamil
2.Lessons From the Household Humidifier Disinfectant Tragedy (HHDT) With Focus on the Chemical Poisoning Surveillance System: Review and Recommendation
Dong-Uk PARK ; Thomas H GASSERT ; Kyung Ehi ZOH ; Dong Young LEE ; Fabrizio SESANA ; Soyoung PARK ; Seong-Yong YOON
Journal of Korean Medical Science 2024;39(21):e178-
Background:
Lessons learned from the Household Humidifier Disinfectant Tragedy (HHDT) in Korea, which poisoned thousands of citizens over a period of years, necessitated an examination of national poison prevention and surveillance systems. The objectives of this study are to identify essential changes needed in chemical poisoning prevention regulations and surveillance systems for effective poison control by comparing recent trends in international poison control center (PCC) operations, and to delineate the critical elements for establishing a state-of-the-art poison control surveillance system in Korea based on recent advances in PCCs with toxicovigilance.
Methods:
A comprehensive review of Korea’s regulatory and surveillance systems for chemical health hazards, with a focus on household products under the HHDT, was conducted. A review of toxicovigilance systems in major countries shows that creating an effective national PCC requires key elements: a centralized database of toxic substances and poisoning cases, mandatory or voluntary reporting of poisoning cases, real-time alerts, collaboration among health organizations, and targeted follow-up of poisoned individuals.
Results:
Significant deficiencies in Korea’s legislation, toxicological data management, and poisoning surveillance systems, explained the inadequate response of the Korean government to the HHDT for nearly 17 years until the end of 2011. Based on a review of PCC toxicovigilance systems in major countries, a national framework with five core components is recommended for establishing a modern comprehensive Korea PCC system with toxicovigilance capacity. The core components include establishment of a centralized database of toxic substances information and clinical poisoning cases, implementation of mandatory or permissive reporting of poisoning cases, real-time alert mechanisms, collaborative systems among health-related organizations, and clinical follow-up of poisoned sub-groups.
Conclusion
A rationale and framework for a state-of-the-art national Korean PCC with toxicovigilance is justified and offered. This proposed system could assist neighboring countries in establishing their own sophisticated, globally integrated PCC networks.
3.The Intracisternal Administration of MEK Inhibitor Attenuates Mechanical and Cold Allodynia in a Rat Model of Compression of the Trigeminal Ganglion.
Min K LEE ; Jeong H YOON ; Min K PARK ; Gwi Y YANG ; Kyung A WON ; Yoon Yub PARK ; Dong K AHN
International Journal of Oral Biology 2010;35(3):75-81
The present study investigated the role of ERK in the onset of mechanical and cold allodynia in a rat model of compression of the trigeminal ganglion by examining changes in the air-puff thresholds and number of scratches following the intracisternal injection of PD98059, a MEK inhibitor. Male Sprague Dawley rats weighing between 250 and 260 g were used. Under anesthesia, the rats were mounted onto a stereotaxic frame and received 4% agar (10 microl) solution to compress the trigeminal ganglion. In the control group, the animals were given a sham operation without the application of agar. Changes in behavior were examined at 3 days before and at 3, 7, 10, 14, 17, 21, 24, 30, and 40 days after surgery. Compression of the trigeminal ganglion significantly decreased the air-puff thresholds. Mechanical allodynia was established within 3 days and persisted over postoperative day 24. To evaluate cold allodynia, nociceptive scratching behavior was monitored after acetone application on the vibrissa pad of the rats. Compression of the trigeminal ganglion was found to produce significant cold allodynia, which persisted for more than 40 days after surgery. On postoperative day 14, the intracisternal administration of 1 microg or 10 microg of PD98059 in the rat model significantly decreased the air-puff thresholds on both the ipsilateral and contralateral side. The intracisternal administration of 10 microg of PD98059 also significantly alleviated the cold allodynia, compared with the vehicle-treated group. These results suggest that central ERK plays an important role in the development of mechanical and cold allodynia in rats with compression of the trigeminal ganglion and that a targeted blockade of this pathway is a potential future treatment strategy for trigeminal neuralgia-like nociception.
Acetone
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Agar
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Anesthesia
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Animals
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Cold Temperature
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Flavonoids
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Humans
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Hyperalgesia
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Male
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Nociception
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Rats
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Rats, Sprague-Dawley
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Salicylamides
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Trigeminal Ganglion
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Trigeminal Neuralgia
4.A Blockade of the Central MAPK Pathway Attenuates Referred Pain in Rats with Complete Freund's Adjuvant-Induced Inflammation of the Temporomandibular Joint.
Kyoung A WON ; Nak H LIM ; Min K LEE ; Min K PARK ; Gwi Y YANG ; Yoon Yub PARK ; Dong K AHN ; Yong C BAE
International Journal of Oral Biology 2010;35(3):83-89
We investigated the role of the central MAPK pathways in extra-territorial (referred) pain resulting from inflammation of the temporomandibular joint (TMJ). Experiments were carried out on male Sprague-Dawley rats weighing 220-280 g. Under anesthesia, these animals were injected with 50 microL of complete Freund's adjuvant (CFA) into the TMJ using a Hamilton syringe. In the control group, saline was injected into the TMJ. To identify the extent of inflammation of the TMJ, Evans blue dye (0.1%, 5 mg/kg) was injected intravenously at 1, 3, 6, 9, 12 and 15 days after CFA injection. The concentration of Evans blue dye in the extracted TMJ tissue was found to be significantly higher in the CFA-treated animals than in the saline-treated group. Air-puff thresholds in the vibrissa pad area were evaluated 3 days before and at 3, 6, 9, 12, 15 and 18 days after CFA injection into the TMJ. Referred mechanical allodynia was established at 3 days, remained until 12 days, and recovered to preoperative levels at 18 days after CFA injection. This referred mechanical allodynia was observed in contralateral side area. To investigate the role of central MAPK pathways, MAPK inhibitors (10 microg) were administrated intracisternally 9 days after CFA injection. SB203580, a p38 MAPK inhibitor, significantly attenuated referred mechanical allodynia, as compared with the vehicle group. PD98059, a MEK inhibitor, also reduced CFA-induced referred mechanical allodynia. These results suggest that TMJ inflammation produces extra-territorial mechanical allodynia, and that this is mediated by central MAPK pathways.
Anesthesia
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Animals
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Evans Blue
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Flavonoids
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Freund's Adjuvant
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Humans
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Hyperalgesia
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Imidazoles
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Inflammation
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Male
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p38 Mitogen-Activated Protein Kinases
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Pain, Referred
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Pyridines
;
Rats
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Rats, Sprague-Dawley
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Syringes
;
Temporomandibular Joint
5.Factors Influencing the Subjective Sexual Function in Patients with Schizophrenia Switched to Olanzapine.
Hyun Jeong LEE ; Hyeri YOON ; S H Samuel HWANG ; Se Hyun KIM ; Dong Chung JUNG ; Nam Young LEE ; Yong Sik KIM ; Yong Min AHN
Korean Journal of Psychopharmacology 2011;22(2):80-88
OBJECTIVE: Sexual dysfunction is highly prevalent in both untreated and treated patients with schizophrenia. Sexual dysfunction is a major cause of poor quality of life, negative attitude to therapy and treatment non-compliance. We thereby conducted this study to better understand the predictors of subjective sexual dysfunction. METHODS: The subjects consisted of 83 patients (46 men; 37 women) who participated in an open label study on switching antipsychotics to olanzapine. All subjects met the Tenth Revision of International Classification of Diseases diagnostic criteria for schizophrenia. To better understand the predictors of subjective sexual dysfunction, we used the Liverpool University Neuroleptic Side-effect Rating scale (LUNSERS), a comprehensive self-rating instrument for assessing and quantifying the subjective adverse events during antipsychotic treatment. All patients were taking antipsychotics at the initiation of the study and were assessed using LUNSERS, the Simpson-Angus Scale (SAS), the Barnes Akathisia Rating scale (BARS), Abnormal Involuntary Movement Scale (AIMS), Clinical Global Impression (CGI), and the Positive and Negative Syndrome Scale (PANSS). They were also checked for their serum prolactin levels and vital signs before and after a 6-week treatment with olanzapine. In order to identify the cross-sectional and longitudinal predictors of LUNSERS hormonal side effect, we carried out multiple regression analyses. RESULTS: Prolactin levels, LUNSERS hormonal side effect, CGI, PANSS, SAS, AIMS, and BARS decreased after a 6-week treatment with olanzapine. At initial evaluation, cross-sectional predictors of LUNSERS hormonal side effect were red herring and allergic reaction subscale, but after the 6-week treatment with olanzapine, none of the variables were found to significantly predict LUNSERS hormonal side effect. Longitudinal predictors of LUNSERS hormonal side effect were LUNSERS extrapyramidal system side effect and prolactin levels. CONCLUSION: These findings suggested relationships among prolactin, extrapyramidal symptom, motor function and sexual dysfunction. After switching to olanzapine, sexual function of the patients improved subjectively. More studies are warranted as these results have significant implications for quality of life and treatment adherence.
Antipsychotic Agents
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Benzodiazepines
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Dyskinesias
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Humans
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Hypersensitivity
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International Classification of Diseases
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Phenothiazines
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Prolactin
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Psychomotor Agitation
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Quality of Life
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Schizophrenia
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Vital Signs
6.Comparing Montreal Cognitive Assessment Performance in Parkinson’s Disease Patients: Age- and Education-Adjusted Cutoffs vs. Machine Learning
Kyeongmin BAEK ; Young Min KIM ; Han Kyu NA ; Junki LEE ; Dong Ho SHIN ; Seok-Jae HEO ; Seok Jong CHUNG ; Kiyong KIM ; Phil Hyu LEE ; Young H. SOHN ; Jeehee YOON ; Yun Joong KIM
Journal of Movement Disorders 2024;17(2):171-180
Objective:
The Montreal Cognitive Assessment (MoCA) is recommended for general cognitive evaluation in Parkinson’s disease (PD) patients. However, age- and education-adjusted cutoffs specifically for PD have not been developed or systematically validated across PD cohorts with diverse education levels.
Methods:
In this retrospective analysis, we utilized data from 1,293 Korean patients with PD whose cognitive diagnoses were determined through comprehensive neuropsychological assessments. Age- and education-adjusted cutoffs were formulated based on 1,202 patients with PD. To identify the optimal machine learning model, clinical parameters and MoCA domain scores from 416 patients with PD were used. Comparative analyses between machine learning methods and different cutoff criteria were conducted on an additional 91 consecutive patients with PD.
Results:
The cutoffs for cognitive impairment decrease with increasing age within the same education level. Similarly, lower education levels within the same age group correspond to lower cutoffs. For individuals aged 60–80 years, cutoffs were set as follows: 25 or 24 years for those with more than 12 years of education, 23 or 22 years for 10–12 years, and 21 or 20 years for 7–9 years. Comparisons between age- and education-adjusted cutoffs and the machine learning method showed comparable accuracies. The cutoff method resulted in a higher sensitivity (0.8627), whereas machine learning yielded higher specificity (0.8250).
Conclusion
Both the age- and education-adjusted cutoff methods and machine learning methods demonstrated high effectiveness in detecting cognitive impairment in PD patients. This study highlights the necessity of tailored cutoffs and suggests the potential of machine learning to improve cognitive assessment in PD patients.
7.Mitochondrial Dysfunction of Immortalized Human Adipose Tissue-Derived Mesenchymal Stromal Cells from Patients with Parkinson's Disease.
Hyo Eun MOON ; Seung Hee YOON ; Yong Suk HUR ; Hyung Woo PARK ; Ji Young HA ; Kyung Hee KIM ; Jung Hee SHIM ; Seung Hyun YOO ; Jin H SON ; Seung Leal PAEK ; In Keyoung KIM ; Jae Ha HWANG ; Dong Gyu KIM ; Han Joon KIM ; Beom Seok JEON ; Sung Sup PARK ; Sun Ha PAEK
Experimental Neurobiology 2013;22(4):283-300
Mitochondrial dysfunction in dopaminergic neurons of patients with idiopathic and familial Parkinson's disease (PD) is well known although the underlying mechanism is not clear. We established a homogeneous population of human adipose tissue-derived mesenchymal stromal cells (hAD-MSCs) from human adult patients with early-onset hereditary familial Parkin-defect PD as well as late-onset idiopathic PD by immortalizing cells with the hTERT gene to better understand the underlying mechanism of PD. The hAD-MSCs from patients with idiopathic PD were designated as "PD", from patients with Parkin-defect PD as "Parkin" and from patients with pituitary adenomas as "non-PD" in short. The pGRN145 plasmid containing hTERT was introduced to establish telomerase immortalized cells. The established hTERT-immortalized cell lines showed chromosomal aneuploidy sustained stably over two-years. The morphological study of mitochondria in the primary and immortalized hAD-MSCs showed that the mitochondria of the non-PD were normal; however, those of the PD and Parkin were gradually damaged. A striking decrease in mitochondrial complex I, II, and IV activities was observed in the hTERT-immortalized cells from the patients with idiopathic and Parkin-defect PD. Comparative Western blot analyses were performed to investigate the expressions of PD specific marker proteins in the hTERT-immortalized cell lines. This study suggests that the hTERT-immortalized hAD-MSC cell lines established from patients with idiopathic and familial Parkin-defect PD could be good cellular models to evaluate mitochondrial dysfunction to better understand the pathogenesis of PD and to develop early diagnostic markers and effective therapy targets for the treatment of PD.
Adult
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Aneuploidy
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Blotting, Western
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Cell Line
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Diagnosis
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Dopaminergic Neurons
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Humans*
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Mesenchymal Stromal Cells*
;
Mitochondria
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Parkinson Disease*
;
Pituitary Neoplasms
;
Plasmids
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Strikes, Employee
;
Telomerase
8.Do Magnets Have the Potential to Serve as a Stabilizer for the Shoulder Joint in Massive Rotator Cuff Tears?: A Biomechanical Cadaveric Study
Yoon Sang JEON ; Sang Hyun KO ; Yun Moon JEON ; Dong Jin RYU ; Jeong Seok KIM ; Hyun Soon PARK ; Min-Shik CHUNG ; Daniel KWAK ; Michelle H. MCGARRY ; Thay Q. LEE
Clinics in Orthopedic Surgery 2023;15(4):616-626
Background:
Disruption of the rotator cuff muscles compromises concavity compression force, which leads to superior migration of the humeral head and loss of stability. A novel idea of using the magnetic force to achieve shoulder stabilization in massive rotator cuff tears (MRCTs) was considered because the magnets can stabilize two separate entities with an attraction force. This study aimed to investigate the biomechanical effect of the magnetic force on shoulder stabilization in MRCTs.
Methods:
Seven fresh frozen cadaveric specimens were used with a customized shoulder testing system. Three testing conditions were set up: condition 1, intact rotator cuff without magnets; condition 2, an MRCT without magnets; condition 3, an MRCT with magnets. For each condition, anterior-posterior translation, superior translation, superior migration, and subacromial contact pressure were measured at 0°, 30°, and 60° of abduction. The abduction capability of condition 2 was compared with that of condition 3.
Results:
The anterior-posterior and superior translations increased in condition 2; however, they decreased compared to condition 2 when the magnets were applied (condition 3) in multiple test positions and loadings (p <0.05). Abduction capability improved significantly in condition 3 compared with that in condition 2, even for less deltoid loading (p < 0.05).
Conclusions
The magnet biomechanically played a positive role in stabilizing the shoulder joint and enabled abduction with less deltoid force in MRCTs. However, to ensure that the magnet is clinically applicable as a stabilizer for the shoulder joint, it is necessary to thoroughly verify its safety in the human body and to conduct further research on technical challenges.