1.Role of microglial activation on neuronal excitability in rat substantia gelatinosa
International Journal of Oral Biology 2020;45(4):225-231
Glial cells, including astrocytes and microglia, interact closely with neurons and modulate pain transmission, particularly under pathological conditions. In this study, we examined the excitability of substantia gelatinosa (SG) neurons of the spinal dorsal horn using a patch clamp recording to investigate the roles of microglial activation in the nociceptive processes of rats. We used xanthine/xanthine oxidase (X/XO), a generator of superoxide anion (O2· – ), to induce a pathological pain condition. X/XO treatment induced an inward current and membrane depolarization. The inward current was significantly inhibited by minocycline, a microglial inhibitor, and fluorocitrate, an astrocyteinhibitor. To examine whether toll-like receptor 4 (TLR4) in microglia was involved in the inward current, we used lipopolysaccharide (LPS), a highly specific TLR4 agonist. The LPS induced inward current, which was decreased by pretreatment with Tak-242, a TLR4-specific inhibitor, and phenyl N-t-butylnitrone, a reactive oxygen species scavenger. The X/XO-induced inward current was also inhibited by pretreatment with Tak-242. These results indicate that the X/XO-induced inward current of SG neurons occurs through activation of TLR4 in microglial cells, suggesting that neuroglial cells modulate the nociceptive process through central sensitization.
2.Fulminant Toxoplasmic Chorioretinitis Following Intravitreal Dexamethasone Implantation
Areum JEONG ; Dong Geun PARK ; Min SAGONG
Journal of the Korean Ophthalmological Society 2019;60(9):896-900
PURPOSE: To report a case of fulminant toxoplasmic chorioretinitis following intravitreal dexamethasone implantation monotherapy in a stabilized toxoplasmic chorioretinitis patient with initial treatment. CASE SUMMARY: A 60-year-old healthy female presented with decreased visual acuity in the left eye. On fundus examination, focal chorioretinitis and yellow-white infiltration were observed. Laboratory work-up, including blood chemistry, complete blood count, and serum serology, was negative; however, toxoplasmic chorioretinitis could not be ruled out. The primary lesion improved with antibiotics and prednisolone treatment. However, the patient did not come in for her follow-up visit, as she had already received an intravitreal dexamethasone implant for recurrent vitreous inflammation elsewhere. On her return, she presented with necrotic retinitis with extensive infiltration. She underwent diagnostic vitrectomy and implant removal. A diagnosis of toxoplasma antigen was confirmed by polymerase chain reaction analysis; the lesions stabilized after anti-toxoplasmic therapy. CONCLUSIONS: Intravitreal dexamethasone implant monotherapy with stabilized toxoplasmic chorioretinitis without systemic antibiotics can lead to fulminant toxoplasmic chorioretinitis and should be used with caution.
Anti-Bacterial Agents
;
Blood Cell Count
;
Chemistry
;
Chorioretinitis
;
Dexamethasone
;
Diagnosis
;
Female
;
Follow-Up Studies
;
Humans
;
Inflammation
;
Intravitreal Injections
;
Middle Aged
;
Polymerase Chain Reaction
;
Prednisolone
;
Retinitis
;
Toxoplasma
;
Toxoplasmosis
;
Visual Acuity
;
Vitrectomy
3.Effects of Reactive Oxygen Species and Nitrogen Species on the Excitability of Spinal Substantia Gelatinosa Neurons.
Joo Young PARK ; Areum PARK ; Sang Woo CHUN
International Journal of Oral Biology 2016;41(3):141-147
Reactive oxygen species (ROS) and nitrogen species (RNS) are both important signaling molecules involved in pain transmission in the dorsal horn of the spinal cord. Xanthine oxidase (XO) is a well-known enzyme for the generation of superoxide anions (O₂˙⁻), while S-nitroso-N-acetyl-DL-penicillamine (SNAP) is a representative nitric oxide (NO) donor. In this study, we used patch clamp recording in spinal slices of rats to investigate the effects of O₂˙⁻ and NO on the excitability of substantia gelatinosa (SG) neurons. We also used confocal scanning laser microscopy to measure XO- and SNAP-induced ROS and RNS production in live slices. We observed that the ROS level increased during the perfusion of xanthine and xanthine oxidase (X/XO) compound and SNAP after the loading of 2',7'-dichlorofluorescin diacetate (H₂DCF-DA), which is an indicator of intracellular ROS and RNS. Application of ROS donors such as X/XO, β-nicotinamide adenine dinucleotide phosphate (NADPH), and 3-morpholinosydnomimine (SIN-1) induced a membrane depolarization and inward currents. SNAP, an RNS donor, also induced membrane depolarization and inward currents. X/XO-induced inward currents were significantly decreased by pretreatment with phenyl N-tert-butylnitrone (PBN; nonspecific ROS and RNS scavenger) and manganese(III) tetrakis(4-benzoic acid) porphyrin (MnTBAP; superoxide dismutase mimetics). Nitro-L-arginine methyl ester (NAME; NO scavenger) also slightly decreased X/XO-induced inward currents, suggesting that X/XO-induced responses can be involved in the generation of peroxynitrite (ONOO⁻). Our data suggest that elevated ROS, especially O₂˙⁻, NO and ONOO⁻, in the spinal cord can increase the excitability of the SG neurons related to pain transmission.
Adenine
;
Animals
;
Humans
;
Membranes
;
Microscopy, Confocal
;
Neurons*
;
Nitric Oxide
;
Nitrogen*
;
Perfusion
;
Peroxynitrous Acid
;
Rats
;
Reactive Oxygen Species*
;
Spinal Cord
;
Spinal Cord Dorsal Horn
;
Substantia Gelatinosa*
;
Superoxide Dismutase
;
Superoxides
;
Tissue Donors
;
Xanthine
;
Xanthine Oxidase
4.Autologous Immunoglobulin Therapy in Patients With Severe Recalcitrant Atopic Dermatitis: Long-Term Changes of Clinical Severity and Laboratory Parameters.
Dong Ho NAHM ; Areum AHN ; Myoung Eun KIM ; Su Mi CHO ; Mi Jung PARK
Allergy, Asthma & Immunology Research 2016;8(4):375-382
This report evaluated long-term changes in clinical severity and laboratory parameters in 3 adult patients with severe recalcitrant atopic dermatitis (AD) who were treated with intramuscular injections of 50 mg of autologous immunoglobulin G (IgG) twice a week for 4 weeks (autologous immunoglobulin therapy, AIGT) and followed up for more than 2 years after the treatment. We observed the following 4 major findings in these 3 patients during the long-term follow-up after AIGT. (1) Two of the 3 patients showed a long-term clinical improvement for more than 36 weeks after AIGT with a maximum decrease in clinical severity score greater than 80% from baseline. (2) These 2 patients also showed long-term decreases in serum total IgE concentrations and peripheral blood eosinophil count for more than 36 weeks after AIGT with a maximum decrease in the two laboratory parameters of allergic inflammatory greater than 70% from baseline. (3) No significant side effect was observed during the 2 years of follow-up period after the AIGT in all 3 patients. (4) Serum levels of IgG anti-idiotype antibodies to the F(ab')2 fragment of autologous IgG administered for the treatment were not significantly changed after AIGT in all 3 patients. These findings suggest that AIGT has long-term favorable effects on both clinical severity and laboratory parameters in selected patients with severe recalcitrant AD. Further studies are required to evaluate the clinical usefulness and therapeutic mechanism of AIGT for AD.
Adult
;
Antibodies
;
Antibodies, Anti-Idiotypic
;
Dermatitis, Atopic*
;
Eosinophils
;
Follow-Up Studies
;
Humans
;
Immunization, Passive*
;
Immunoglobulin E
;
Immunoglobulin G
;
Immunoglobulins*
;
Immunomodulation
;
Injections, Intramuscular
5.Ryanodine Receptor-mediated Calcium Release Regulates Neuronal Excitability in Rat Spinal Substantia Gelatinosa Neurons.
International Journal of Oral Biology 2015;40(4):211-216
Nitric Oxide (NO) is an important signaling molecule in the nociceptive process. Our previous study suggested that high concentrations of sodium nitroprusside (SNP), a NO donor, induce a membrane hyperpolarization and outward current through large conductances calcium-activated potassium (BKca) channels in substantia gelatinosa (SG) neurons. In this study, patch clamp recording in spinal slices was used to investigate the sources of Ca2+ that induces Ca2+-activated potassium currents. Application of SNP induced a membrane hyperpolarization, which was significantly inhibited by hemoglobin and 2-(4-carboxyphenyl) -4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide potassium salt (c-PTIO), NO scavengers. SNP-induced hyperpolarization was decreased in the presence of charybdotoxin, a selective BKCa channel blocker. In addition, SNP-induced response was significantly blocked by pretreatment of thapsigargin which can remove Ca2+ in endoplasmic reticulum, and decreased by pretreatment of dentrolene, a ryanodine receptors (RyR) blocker. These data suggested that NO induces a membrane hyperpolarization through BKca channels, which are activated by intracellular Ca2+ increase via activation of RyR of Ca2+ stores.
Animals
;
Calcium*
;
Charybdotoxin
;
Endoplasmic Reticulum
;
Humans
;
Membranes
;
Neurons*
;
Nitric Oxide
;
Nitroprusside
;
Potassium
;
Rats*
;
Ryanodine Receptor Calcium Release Channel
;
Ryanodine*
;
Substantia Gelatinosa*
;
Thapsigargin
;
Tissue Donors
6.Successful Implantation of an Implantable Cardioverter-Defibrillator Through a Persistent Left Superior Vena Cava.
Areum KIM ; Dae Hyeok KIM ; Jun KWAN ; Keum Soo PARK ; Woo Hyung LEE
Korean Journal of Medicine 2014;87(3):328-333
The prevalence of persistent left superior vena cava (PLSVC) in the general population has been estimated to be approximately 0.3%, as determined by autopsy. PLSVC is hemodynamically insignificant if it is not associated with other congenital cardiac anomalies, and usually goes unrecognized until a left superior approach to the heart is required. Here, we report a 60-year-old male diagnosed with dilated cardiomyopathy, who had survived an episode of sudden cardiac arrest with documented ventricular fibrillation. PLSVC was recognized incidentally while implanting an implantable cardioverter-defibrillator (ICD). The ICD was successfully implanted through the left superior vena cava via the coronary sinus using a straight stylet and an active fixation device.
Autopsy
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Cardiomyopathy, Dilated
;
Coronary Sinus
;
Death, Sudden, Cardiac
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Defibrillators, Implantable*
;
Heart
;
Humans
;
Male
;
Middle Aged
;
Prevalence
;
Vena Cava, Superior*
;
Ventricular Fibrillation
7.A case of symptomatic splenic infarction in vivax malaria.
Areum KIM ; Yun Kyu PARK ; Jin Soo LEE ; Moon Hyun CHUNG ; Eun Sil KIM
The Korean Journal of Parasitology 2007;45(1):55-58
Splenic infarction is a rare complication in malaria cases, and is caused primarily by Plasmodium falciparum. Recently in South Korea, only P. vivax has prevailed since 1993. Although the probability that symptomatic splenic infarction may occur in vivax malaria cases is considered relatively high, there have never been any case reports describing the occurrence of symptomatic splenic infarction in cases of vivax malaria. A 34-year-old man presented with fever that had persisted for 5 days. P. vivax infection was verified using a peripheral blood smear, and chloroquine was utilized to treat the fever successfully. Six days later, the patient developed pain in the left upper abdomen, which was diagnosed as splenic infarction by computed tomography.
Adult
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Animals
;
Humans
;
Malaria, Vivax/blood/*complications/drug therapy
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Male
;
Plasmodium vivax/*isolation & purification
;
Primaquine/therapeutic use
;
Splenic Infarction/blood/*parasitology
8.A case of symptomatic splenic infarction in vivax malaria.
Areum KIM ; Yun Kyu PARK ; Jin Soo LEE ; Moon Hyun CHUNG ; Eun Sil KIM
The Korean Journal of Parasitology 2007;45(1):55-58
Splenic infarction is a rare complication in malaria cases, and is caused primarily by Plasmodium falciparum. Recently in South Korea, only P. vivax has prevailed since 1993. Although the probability that symptomatic splenic infarction may occur in vivax malaria cases is considered relatively high, there have never been any case reports describing the occurrence of symptomatic splenic infarction in cases of vivax malaria. A 34-year-old man presented with fever that had persisted for 5 days. P. vivax infection was verified using a peripheral blood smear, and chloroquine was utilized to treat the fever successfully. Six days later, the patient developed pain in the left upper abdomen, which was diagnosed as splenic infarction by computed tomography.
Adult
;
Animals
;
Humans
;
Malaria, Vivax/blood/*complications/drug therapy
;
Male
;
Plasmodium vivax/*isolation & purification
;
Primaquine/therapeutic use
;
Splenic Infarction/blood/*parasitology
9.Pre- and Postsynaptic Actions of Reactive Oxygen Species and Nitrogen Species in Spinal Substantia Gelatinosa Neurons
International Journal of Oral Biology 2018;43(4):209-216
Reactive oxygen species (ROS) and nitrogen species (RNS) are involved in cellular signaling processes as a cause of oxidative stress. According to recent studies, ROS and RNS are important signaling molecules involved in pain transmission through spinal mechanisms. In this study, a patch clamp recording was used in spinal slices of rats to investigate the action mechanisms of O₂˙⁻ and NO on the excitability of substantia gelatinosa (SG) neuron. The application of xanthine and xanthine oxidase (X/XO) compound, a ROS donor, induced inward currents and increased the frequency of spontaneous excitatory postsynaptic currents (sEPSC) in slice preparation. The application of S-nitroso-N-acetyl-DLpenicillamine (SNAP), a RNS donor, also induced inward currents and increased the frequency of sEPSC. In a single cell preparation, X/XO and SNAP had no effect on the inward currents, revealing the involvement of presynaptic action. X/XO and SNAP induced a membrane depolarization in current clamp conditions which was significantly decreased by the addition of thapsigargin to an external calcium free solution for blocking synaptic transmission. Furthermore, X/XO and SNAP increased the frequency of action potentials evoked by depolarizing current pulses, suggesting the involvement of postsynaptic action. According to these results, it was estblished that elevated ROS and RNS in the spinal cord can sensitize the dorsal horn neurons via pre- and postsynaptic mechanisms. Therefore, ROS and RNS play similar roles in the regulation of the membrane excitability of SG neurons.
Action Potentials
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Animals
;
Calcium
;
Excitatory Postsynaptic Potentials
;
Humans
;
Membranes
;
Neurons
;
Nitric Oxide
;
Nitrogen
;
Oxidative Stress
;
Posterior Horn Cells
;
Rats
;
Reactive Oxygen Species
;
Spinal Cord
;
Substantia Gelatinosa
;
Superoxides
;
Synaptic Transmission
;
Thapsigargin
;
Tissue Donors
;
Xanthine
;
Xanthine Oxidase
10.Health Behaviors and Lifestyle Patterns of Elderly Living Alone in Korea
Chae Lin JOO ; Jin Ju PARK ; Areum KIM ; Na Lee PARK ; Jisun LIM ; Hye Soon PARK
Korean Journal of Family Practice 2019;9(3):247-253
BACKGROUND: Korea's population is aging rapidly. Aged people who lead a solitary life are in a state of social isolation and face a greater risk of lower quality of life. The purpose of this study was to analyze the health behaviors and lifestyle patterns of aged people who lead a solitary life in Korea.METHODS: We analyzed 4,471 subjects (1,933 men and 2,538 women)-aged people aged 65 or above-based on data from the Korea National Health and Nutrition Examination Survey VI (2013–2015). The odds ratios (ORs) and 95% confidence intervals (CIs) were analyzed using multivariate logistic regression analysis adjusted with age, household income level, occupational status, and geographical region.RESULTS: Socioeconomic status was lower in aged people who lead a solitary life than in those living with family. The ORs for frequent eating out alone (OR=2.93; 95% CI 1.83–4.38), daily eating out alone (OR=2.40; 95% CI 1.25–4.60), smoking (OR=1.57; 95% CI 1.06–2.32), feeling sick or uncomfortable (OR=1.59; 95% CI 1.08–2.36), feeling depressed (OR=4.10; 95% CI 2.53–6.65), and suicide ideation (OR=2.06; 95% CI 1.21–3.51) were significantly higher in male subjects who lead a solitary life. The ORs for frequent eating out alone (OR=1.57; 95% CI 1.10–2.24) and inadequate sleep duration (OR=1.29; 95% CI 1.03–1.61) were significantly higher in female subjects who lead a solitary life.CONCLUSION: Aged people who lead a solitary life exhibited unhealthy behaviors and poor mental health. The elderly men who lead a solitary life faced higher risk of poor health than the women. Integrated management of lifestyle behaviors is required to improve the quality of health in aged people who lead a solitary life.
Aged
;
Aging
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Eating
;
Employment
;
Family Characteristics
;
Female
;
Health Behavior
;
Humans
;
Korea
;
Life Style
;
Logistic Models
;
Male
;
Mental Health
;
Nutrition Surveys
;
Nutritional Status
;
Odds Ratio
;
Quality of Life
;
Smoke
;
Smoking
;
Social Class
;
Social Isolation
;
Suicide