• The Korean Journal of Physiology and Pharmacology
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• 제28권1호
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• pp.93-103
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• 2024

Satellite glial cells (SGCs), a major type of glial cell in the autonomic ganglia, closely envelop the cell body and even the synaptic regions of a single neuron with a very narrow gap. This structurally unique organization suggests that autonomic neurons and SGCs may communicate reciprocally. Glial Ca²⁺ signaling is critical for controlling neural activity. Here, for the first time we identified the machinery of store-operated Ca²⁺ entry (SOCE) which is critical for cellular Ca²⁺ homeostasis in rat sympathetic ganglia under normal and pathological states. Quantitative realtime PCR and immunostaining analyses showed that Orai1 and stromal interaction molecules 1 (STIM1) proteins are the primary components of SOCE machinery in the sympathetic ganglia. When the internal Ca²⁺ stores were depleted in the absence of extracellular Ca²⁺, the number of plasmalemmal Orai1 puncta was increased in neurons and SGCs, suggesting activation of the Ca²⁺ entry channels. Intracellular Ca²⁺ imaging revealed that SOCE was present in SGCs and neurons; however, the magnitude of SOCE was much larger in the SGCs than in the neurons. The SOCE was significantly suppressed by GSK7975A, a selective Orai1 blocker, and Pyr6, a SOCE blocker. Lipopolysaccharide (LPS) upregulated the glial fibrillary acidic protein and Toll-like receptor 4 in the sympathetic ganglia. Importantly, LPS attenuated SOCE via downregulating Orai1 and STIM1 expression. In conclusion, sympathetic SGCs functionally express the SOCE machinery, which is indispensable for intracellular Ca²⁺ signaling. The SOCE is highly susceptible to inflammation, which may affect sympathetic neuronal activity and thereby autonomic output.

• Imaging Science in Dentistry
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• 제31권2호
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• pp.85-91
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• 2001

Purpose: To evaluate the effect of the slice thickness and the size of region of interest (ROI) on CT number using quantitative CT phantom Materials and Methods: The phantom containing 150 mg/cc, 75 mg/cc and 0 mg/cc calcium hydroxyapatite was scanned with 1, 3, 5 and 10 mm slice thicknesses by single energy quantitative computed tomography (QCT). CT numbers were measured on center position of the phantom. Shape of ROI was circular and sizes were 1, 3, 5, 11, 16, 21, 26 and 33 mm². ANOVA and Tukey's multiple comparison method were performed for statistical comparison of CT numbers according to different slice thicknesses. Coefficient of variation of CT number measured in each size of ROI was evaluated in same slice thickness. Results : CT numbers had statistically significant difference according to slice thicknesses (p<0.05). As the slice thickness increased, CT number also increased. As the density of phantom became lower and the size of ROI became smaller, the coefficient of variation of CT number increased. When the size of ROI was more than 11 mm² in 1 mm slice thickness, 5 mm² in 3 mm slice thickness and 3 mm² in 5 mm slice thickness, the coefficient of variation became consistent. In 10 mm slice thickness, the size of ROI had little effect on the coefficient of variation. Conclusion: CT number had variation according to the slice thickness and the size of ROI although the object was homogeneous. The slice thickness and the size of ROI are critical factors in precision of the CT number measurements.

• The Korean Journal of Physiology and Pharmacology
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• 제21권6호
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• pp.591-598
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• 2017

Propofol is known to cause vasorelaxation of several systemic vascular beds. However, its effect on the pulmonary vasculature remains controversial. In the present study, we investigated the effects of propofol on human pulmonary arteries obtained from patients who had undergone surgery. Arterial rings were mounted in a Multi-Myograph system for measurement of isometric forces. U46619 was used to induce sustained contraction of the intrapulmonary arteries, and propofol was then applied (in increments from $10-300{\mu}m$). Arteries denuded of endothelium, preincubated or not with indomethacin, were used to investigate the effects of propofol on isolated arteries. Propofol exhibited a bifunctional effect on isolated human pulmonary arteries contracted by U46619, evoking constriction at low concentrations ($10-100{\mu}m$) followed by secondary relaxation (at $100-300{\mu}m$). The extent of constriction induced by propofol was higher in an endothelium-denuded group than in an endothelium-intact group. Preincubation with indomethacin abolished constriction and potentiated relaxation. The maximal relaxation was greater in the endothelium-intact than the endothelium-denuded group. Propofol also suppressed $CaCl_2$-induced constriction in the 60 mM $K^+$-containing $Ca^{2+}$-free solution in a dose-dependent manner. Fluorescent imaging of $Ca^{2+}$ using fluo-4 showed that a 10 min incubation with propofol ($10-300{\mu}m$) inhibited the $Ca^{2+}$ influx into human pulmonary arterial smooth muscle cells induced by a 60 mM $K^+$-containing $Ca^{2+}$-free solution. In conclusion, propofol-induced arterial constriction appears to involve prostaglandin production by cyclooxygenase in pulmonary artery smooth muscle cells and the relaxation depends in part on endothelial function, principally on the inhibition of calcium influx through L-type voltage-operated calcium channels.

• The Korean Journal of Physiology and Pharmacology
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• 제8권1호
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• pp.57-63
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• 2004

Fluoxetine, a widely used anti-depressant compound, has several additional effects, including blockade of voltage-gated ion channels. We examined whether fluoxetine affects ATP-induced calcium signaling in PC12 cells by using fura-2-based digital calcium imaging and assay for $[^3H]-inositol$ phosphates (IPs). Treatment with ATP $(100\;{\mu}M)$ for 2 min induced $[Ca^{2+}]_i$ increases. The ATP-induced $[Ca^{2+}]_i$ increases were significantly decreased by removal of extracellular $Ca^{2+}$ and treatment with the inhibitor of endoplasmic reticulum $Ca^{2+}$ ATPase thapsigargin $(1\;{\mu}M)$. Treatment with fluoxetine for 5 min blocked the ATP-induced $[Ca^{2+}]_i$ increase concentration-dependently. Treatment with fluoxetine $(30\;{\mu}M)$ for 5 min blocked the ATP-induced $[Ca^{2+}]_i$ increase following removal of extracellular $Ca^{2+}$ and depletion of intracellular $Ca^{2+}$ stores. While treatment with the L-type $Ca^{2+}$ channel antagonist nimodipine for 10 min inhibited the ATP-induced $[Ca^{2+}]_i$ increases significantly, treatment with fluoxetine alone blocked the ATP-induced responses. Treatment with fluoxetine also inhibited the 50 mM $K^+-induced$ $[Ca^{2+}]_i$ increases completely. However, treatment with fluoxetine did not inhibit the ATP-induced $[^3H]-IPs$ formation. Collectively, we conclude that fluoxetine inhibits ATP-indueed $[Ca^{2+}]_i$ increases in PC12 cells by inhibiting both an influx of extracellular $Ca^{2+}$ and a release of $Ca^{2+}$ from intracellular stores without affecting IPs formation.

• 한국지반환경공학회 논문집
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• 제25권5호
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• pp.29-37
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• 2024

본 연구는 산화칼슘 개질제로 제강슬래그를 사용하여 연약점토와 혼합 시 발생하는 화학적 성분의 변화가 수경성 및 양생시간에 따른 압축강도 발현 특성을 파악하고자 XRF시험과 SEM 촬영, 베인전단강도, 일축압축강도시험을 수행하였다. 제강슬래그로부터 용출되는 칼슘(Ca)은 점토 내 Ca 함량을 증가시키고, SiO₂ 및 Al₂O₃ 성분과의 화학적 반응으로 칼슘실리카게이트 수화물 (CaO-SiO₂-H₂O) 반응으로 점토의 피막층이 형성되어 결정체 입자수를 증가시킨다. 따라서, 중량혼합비 Rss 30%(제강슬래그 30% + 점토 70%) 상태에서 초기 비활성영역의 베인전단강도는 4.4~18.4kN/m²로 나타났다. 활성영역의 경우 양생시간 480시간 경과 시 최대일축압축강도는 431.8kN/m²까지 증가되었으며, 이는 포졸란 반응에 의해 점토의 겉보기 점착(Attraction) 강도를 증가시킨다. 본 연구를 통해 토목현장에서 제강슬래그의 재활용을 위해 연약점토와 혼합 시 제강슬래그의 혼합율(Rss)에 따라 연약점토는 강도발현이 되므로 활용성을 높일 수 있다.

• 대한영상의학회지
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• 제85권2호
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• pp.327-344
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• 2024

부갑상선은 부갑상선 호르몬(parathyroid hormone; 이하 PTH)을 생성하여 칼슘 대사를 조절하는 작은 내분비선으로 구성되어 있다. 일반적으로 갑상선 뒤에 4개의 부갑상선이 위치해 있으나 개수 또는 위치는 개인차가 있으며 4개보다 많거나 적은 경우들이 있다. 부갑상선 질환은 부갑상선 기능 장애와 관련이 있으며, 부갑상선 자체의 문제 또는 신장질환으로 인한 비정상적인 혈청 칼슘 수치로 인해 발생할 수 있다. 최근 건강검진이 보편화되면서 우연히 비정상적으로 높은 혈청 칼슘 값이 발견되어 PTH 검사, 초음파, 테크네튬-99m 세스타 미비 부갑상선 스캔, 단일광자방출단층촬영/컴퓨터단층촬영(SPECT/CT), 4차원 컴퓨터단층촬영(4D-CT), 그리고 양전자방출단층촬영/컴퓨터단층촬영(PET/CT) 등의 추가적인 검사가 시행된다. 그러나 부갑상선은 여전히 영상의학과 의사에게 익숙하지 않은 기관이다. 이 종설에서 부갑상선의 해부학, 병태생리, 영상 및 임상 소견에 대해 알아보고자 한다.

• 대한영상의학회지
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• 제84권6호
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• pp.1324-1336
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• 2023

목적 이첨 대동맥 판막의 아형과 판막 석회화의 정도에 따른 심장 CT와 경흉부심초음파의 이첨 대동맥 판막 진단 능력을 비교해 보고자 한다. 대상과 방법 대동맥 판막 치환술 전 심장 CT와 경흉부 심초음파를 시행한 266명의 환자(이첨 대동맥 판막, 106명; 삼첨 대동맥 판막, 166명)를 후향적으로 포함하였다. 심장 CT를 이용하여 판막의 모양을 평가하였고, 관상동맥 칼슘 측정 CT를 이용하여 판막의 칼슘 정도를 정량화하였다. 대동맥 판막은 융합형과 2-대동맥동형 아형으로 분류하였다. 심장 CT와 경흉부 심초음파의 진단정확도는 수술 소견을 대비표준으로 하여 계산하였다. 결과 CT는 이첨 대동맥 판막을 진단함에 있어서 경흉부 심초음파보다 민감도, 음성 예측도, 정확도에서 통계적으로 유의하게 높은 값을 보여주었다(각각 p < 0.001, p < 0.001, p = 0.003). 경흉부 심초음파는 판막의 석회화가 증가할수록 민감도가 감소하는 경향을 보였다. CT와 경흉부 심초음파 간의 진단 오류율은 2-대동맥동형 아형에서 10.9%, 융합형 아형에서 28.3%였다(p = 0.044). 결론 심장 CT는 이첨 대동맥 판막을 진단함에 있어 경흉부 심초음파보다 높은 진단능을 보여주며, 특히 판막 석회화가 심하거나 융합형의 아형인 환자에서 이첨 대동맥 판막을 진단하는데 도움을 줄 수 있다.

• Imaging Science in Dentistry
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• 제30권1호
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• pp.80-86
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• 2000

A 37-year-old male with the complaint of intermittent gingival swelling and dull pain associated with the food impaction of the mandibular third molar area was referred to our department of Chonbuk National University Hospital. The dental history of the patient showed that he had extracted the maxillary left third molar without complications two years ago. Intraoral and panoramic radiographs showed diffuse increased radiopacity of the maxilla and mandible. The trabecular pattern was obliterated. Postero-anterior skull and lateral skull radiographs showed thickening of cortical bone and diffuse increased radiopacity of the skull. Additional radiographs showed similar changes in the lumbar spine, clavicles, iliac bone and femur. However, no evidence of osteomyelitis was observed clinically and radiographically. Laboratory findings showed normal values of serum calcium, phosphorus, and alkaline phosphatase. Based on the radiographic examinations and the laboratory findings, final diagnosis was made as a benign osteopetrosis.

• Imaging Science in Dentistry
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• 제47권4호
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• pp.275-279
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• 2017

Soft tissue calcification is a pathological condition in which calcium and phosphate salts are deposited in the soft tissue organic matrix. This study presents an unusual calcification noted in the cartilaginous portion of the Eustachian tube. A 67-year-old woman presented for dental treatment, specifically for implant placement, and cone-beam computed tomography (CBCT) was performed. The CBCT scan was reviewed by a board-certified oral and maxillofacial radiologist and revealed incidental findings of 2 distinct calcifications in the cartilaginous portion of the Eustachian tube. To the authors' knowledge, no previous study has reported the diagnosis of Eustachian tube calcification using CBCT. This report describes an uncommon variant of Eustachian tube calcification, which has a significant didactic value because such cases are seldom illustrated either in textbooks or in the literature. This case once again underscores the importance of having CBCT scans evaluated by a board-certified oral and maxillofacial radiologist.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.2.1-2.7
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• 2018

With the development of computer-aided design/computer-aided manufacturing (CAD/CAM) technology, it has been possible to reconstruct the cranio-maxillofacial defect with more accurate preoperative planning, precise patient-specific implants (PSIs), and shorter operation times. The manufacturing processes include subtractive manufacturing and additive manufacturing and should be selected in consideration of the material type, available technology, post-processing, accuracy, lead time, properties, and surface quality. Materials such as titanium, polyethylene, polyetheretherketone (PEEK), hydroxyapatite (HA), poly-DL-lactic acid (PDLLA), polylactide-co-glycolide acid (PLGA), and calcium phosphate are used. Design methods for the reconstruction of cranio-maxillofacial defects include the use of a pre-operative model printed with pre-operative data, printing a cutting guide or template after virtual surgery, a model after virtual surgery printed with reconstructed data using a mirror image, and manufacturing PSIs by directly obtaining PSI data after reconstruction using a mirror image. By selecting the appropriate design method, manufacturing process, and implant material according to the case, it is possible to obtain a more accurate surgical procedure, reduced operation time, the prevention of various complications that can occur using the traditional method, and predictive results compared to the traditional method.