• 대한핵의학회지
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• 제32권5호
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• pp.433-435
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• 1998

Recent progress of technology permits us to assess ventricular function and wall motion as well as myocardial perfusion using electrocardiographic gated myocardial perfusion single photon emission computed tomography (GM-SPECT). It is interesting that echocardiography and magnetic resonance imaging are moving in the same direction with the use of contrast medium to assess myocardial perfusion. A valid fundamental basis for a new technology is essential for a successful competition. Lee et al. report in this issue the reproducibility of serial measurement of left ventricular function including systolic wall thickening using a novel statistical method. It has important implications such as nitroglycerin or dobutamine application during GM-SPECT. The field of nuclear cardiology must continue to strive toward more sophisticated but straightforward evaluation of cardiac diseases.

• Nuclear Medicine and Molecular Imaging
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• 제43권3호
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• pp.222-228
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• 2009

Risk stratification and assessment of prognosis in patients with known or suspected CAD is of crucial important for the practice of contemporary medicine. Noninvasive testing such as myocardial perfusion scintigraphy, coronary artery calcium scoring or CT coronary angiography is increasingly being used to determine the need for aggressive medical therapy and to select patients for catheterization. The integrated anatomic and functional information may provide more additional information for the cardiologist or other clinician by the improved risk stratification and diagnostic accuracy of integrated techniques. The development of SPECT/CT or PET/CT hybrid systems is therefore of important value for the nuclear cardiology.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10057-10059
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• 2015

Positron emission tomography (PET) as the functional component of current hybrid imaging (like PET/CT or PET/MRI) seems to dominate the horizon of medical imaging in coming decades. $^{18}$Flourodeoxyglucose ($^{18}FDG$) is the most commonly used probe in oncology and also in cardiology and neurology around the globe. However, the major capital cost and exorbitant running expenditure of low to medium energy cyclotrons (about 20 MeV) and radiochemistry units are the seminal reasons of low number of cyclotrons but mushroom growth pattern of PET scanners. This fact and longer half-life of $^{18}F$ (110 minutes) have paved the path of a centralized model in which $^{18}FDG$ is produced by commercial PET radiopharmacies and the finished product (multi-dose vial with tungsten shielding) is dispensed to customers having only PET scanners. This indeed reduced the cost but has limitations of dependence upon timely arrival of daily shipments as delay caused by any reason results in cancellation or rescheduling of the PET procedures. In recent years, industry and academia have taken a step forward by producing low energy, table top cyclotrons with compact and automated radiochemistry units (Lab-on-Chip). This decentralized strategy enables the users to produce on-demand doses of PET probe themselves at reasonably low cost using an automated and user-friendly technology. This technological development would indeed provide a real impetus to the availability of complete set up of PET based molecular imaging at an affordable cost to the developing countries.

• 대한핵의학회지
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• 제38권2호
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• pp.175-179
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• 2004

Molecular nuclear cardiac imaging has included Tc-99m Annexin imaging to visualize myocardial apoptosis, but is now usually associated with gene therapy and cell-based therapy. Cardiac gene therapy was not successful so far but cardiac reporter gene imaging was made possible using HSV-TK (herpes simplex virus thymidine kinase) and F-18 FHBG (fluoro-hydroxymethylbutyl guanine) or I-124 FIAU (fluoro-deoxyiodo-arabino-furanosyluracil). Gene delivery was performed by needic injection with or without catheter guidance. Tk expression did not last longer than 2 weeks in myocardium. Cell-based therapy of ischemic heart or failing heart looks promising, but biodistribution and differentiation of transplanted cells are not known. Reporter genes can be transfected to the stem/progenitor cells and cells containing these genes can be transplanted to the recipients using catheter-based purging or injection. Repeated imaging should be available and if promoter are varied to let express reporter transgenes, cellular (trans)differentiation can be studied. NIS (sodium iodide symporter) or D2R receptor genes are promising in this aspect.

• Nuclear Medicine and Molecular Imaging
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• 제43권3호
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• pp.174-178
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• 2009

Many radiopharmaceuticals have been developed and wildy used in the imaging cardiac function. Myocardial perfusion imaging (MPI) is a well established noninvasive method of assessing coronary blood flow and has been widely used in patients diagnosed or suspected with coronary artery diseases. The innovation of radiopharmaceuticals used in the cardiac imaging is one of the most important contributors to the development of nuclear cardiology. Thallium-201 and various technetium-99m agents have been globally used for myocardial perfusion SPEG, and N-13 ammonia (13NH3), rubidium-82 (82Rb), 0-15 water (H2150) for myocardial perfusion PET. As well as the cardiac perfusion studies, new radiopharmaceuticals that visualize fat metabolism or receptors of the sympathetic nervous system have successfully been applied to clinical practice. Useful information can be obtained for diagnosing coronary artery disease, evaluating patients' condition, or assessing therapeutic effects. In this review, we describe the characteristics and clinical usefulness of radiopharmaceuticals used for cardiac SPEG and PET.

• The Korean Journal of Physiology and Pharmacology
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• 제25권6호
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• pp.533-543
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• 2021

Myocardial fibrosis (MF) is the result of persistent and repeated aggravation of myocardial ischemia and hypoxia, leading to the gradual development of heart failure of chronic ischemic heart disease. Triptolide (TPL) is identified to be involved in the treatment for MF. This study aims to explore the mechanism of TPL in the treatment of MF. The MF rat model was established, subcutaneously injected with isoproterenol and treated by subcutaneous injection of TPL. The cardiac function of each group was evaluated, including LVEF, LVFS, LVES, and LVED. The expressions of ANP, BNP, inflammatory related factors (IL-1β, IL-18, TNF-α, MCP-1, VCAM1), NLRP3 inflammasome factors (NLRP3, ASC) and fibrosis related factors (TGF-β1, COL1, and COL3) in rats were dete cted. H&E staining and Masson staining were used to observe myocardial cell inflammation and fibrosis of rats. Western blot was used to detect the p-P65 and t-P65 levels in nucleoprotein of rat myocardial tissues. LVED and LVES of MF group were significantly upregulated, LVEF and LVFS were significantly downregulated, while TPL treatment reversed these trends; TPL treatment downregulated the tissue injury and improved the pathological damage of MF rats. TPL treatment downregulated the levels of inflammatory factors and fibrosis factors, and inhibited the activation of NLRP3 inflammasome. Activation of NLRP3 inflammasome or NF-κB pathway reversed the effect of TPL on MF. Collectively, TPL inhibited the activation of NLRP3 inflammasome by inhibiting NF-κB pathway, and improved MF in MF rats.

• 대한핵의학회지
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• 제32권3호
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• pp.250-258
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• 1998

목적 : ATP는 작용 시간이 빠르고 반감기가 짧은 효과적인 관상동맥 확장제로 알려져 있어 이를 심근관류 SPECT의 부하 약물로 사용 할 때에 부작용의 빈도와 안전성, 그 진단적 가치에 대해 알아 보고자하였다. 대상 및 방법: 관상동맥 질환이 의심되는 319명의 환자를 대상으로 ATP 부하(0.08 mg/kg/ min for 6min) T1-201 심근관류 SPECT를 실시하여 그 부작용을 조사하고 관상동맥 조영술과 비교하였다. 결과: 76.5%의 환자에서 부작용이 발생하였으나 일시적이고 경미하였으며, 모든 환자에서 ATP 주입을 끝낼 수 있었고 aminophylline이 필요했던 환자는 2명이었다. 관상동맥 조영술과 비교한 결과, 예민도 80%, 특이도 90% 였다. 결론: 6분간 0.08mg/kg/min의 ATP 주입 용량을 사용한 본 연구 결과에서 ATP 부하 심근관류 SPECT는 관상동맥 질환의 진단에서 adenosine이나 dipyridamole을 이용했을 때보다 부작용의 발생 빈도 및 부작용의 정도가 낮아 안전하게 사용될 수 있으며 진단 성능도 동등한 것으로 생각된다.

• 한국발생생물학회지:발생과생식
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• 제12권2호
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• pp.159-168
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• 2008

Nanog is a newly identified member of the homeobox family of DNA binding transcription factors that functions to maintain the undifferentiated state of stem cells. However, molecular mechanisms underlying the function of Nanog remain largely unknown. To elucidate the regulatory roles of Nanog involved in maintenance of P19 embryonal carcinoma (EC) stem cells, we transfected three small interfering RNA (siRNA) duplexes targeted against different regions of the Nanog gene into P19 cells. The Nanog siRNA-100 duplexes effectively decreased the expression of Nanog up to 30.7% compared to other two Nanog siRNAs, the Nanog siRNA-400 (67.9 %) and -793 (53.0%). When examined by RT-PCR and real-time PCR, the expression of markers for pluripotency such as Fgf4, Oct3/4, Rex1, Sox1 and Yes was downregulated at 48 h after transfection with Nanog siRNA-100. Furthermore, expression of the ectodermal markers, Fgf5 and Isl1 was reduced by Nanog knockdown. By contrast, the expression of other markers for pluripotency such as Cripto, Sox2 and Zfp57 was not affected by Nanog knockdown at this time. On the other hand, the expression of Lif/Stat3 pathway molecules and of the endoderm markers including Dab2, Gata4, Gata6 and the germ cell nuclear factor was not changed by Nanog knockdown. The results of this study demonstrated that the knockdown of Nanog expression by RNA interference in P19 cells was sufficient to modulate the expression of pluripotent markers involved in the self-renewal of EC stem cells. These results provide the valuable information on potential downstream targets of Nanog and add to our understanding of the function of Nanog in P19 EC stem cells.

• Asian Pacific Journal of Cancer Prevention
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• 제16권1호
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• pp.377-380
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• 2015

Background: There is strong evidence that delayed diagnosis of breast cancer is associated with poor survival. Our objectives were to determine the frequency of breast cancer patients with delayed presentation, the reasons of delay and its association with different socio-demographic variables in our North Pakistan setting. Materials and Methods: We interviewed 315 histologically confirmed breast cancer patients. Delay was defined as more than 3 months from appearance of symptoms to consultation with a doctor. Questions were asked from each patient which could reflect their understanding about the disease and which could be the likely reasons for their delayed presentation. Results: 39.0 % (n=123) of patients presented late and out of those, 40.7% wasted time using alternative medicines; 25.2 % did not having enough resources; 17.1 % presented late due to painless lump; 10.6% felt shyness and 6.5% presented late due to other reasons. Higher age, negative family history, < 8 school years of education and low to middle socio-economic status were significantly associated with delayed presentation (p< 0.05). Education and socioeconomic status were two independent variables related to the delayed presentation after adjustment for others (OR of 2.26, 2.29 and 95%CI was 1.25-4.10, 1.06-4.94 respectively). Conclusions: Significant numbers of women with breast cancer in North Pakistan experience presentation delay due to their misconceptions about the disease. Coordinated efforts with public health departments are needed to educate the focused groups and removing the barriers identified in the study. Long term impact will be reduced overall burden of the disease in the region.

• Journal of Yeungnam Medical Science
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• 제38권2호
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• pp.95-106
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• 2021

Infections involving the heart are becoming increasingly common, and a timely diagnosis of utmost importance, despite its challenges. F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is a recently introduced diagnostic tool in cardiology. This review focuses on the current evidence for the use of FDG PET/CT in the diagnosis of infective endocarditis, cardiac implantable device infection, left ventricular assist device infection, and secondary complications. The author discusses considerations when using FDG PET/CT in routine clinical practice, patient preparation for reducing physiologic myocardial uptake, acquisition of images, and interpretation of PET/CT findings. This review also functions to highlight the need for a standardized acquisition protocol.