• Nuclear Medicine and Molecular Imaging
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• 제40권6호
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• pp.279-292
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• 2006

Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of biomedical research. These tools have been validated recently in variety of research models, and have born shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene delivery and/or expression. This article reviews the use of PET technologies as they have been used in imaging biological processes for molecular imaging applications. The studies published to date demonstrate that noninvasive imaging tools will help to accelerate pre-clinical model validation as well as allow for clinical monitoring of human diseases.

• Translational and Clinical Pharmacology
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• 제25권2호
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• pp.67-73
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• 2017

Glimepiride, a third generation sulfonylurea, is an antihyperglycemic agent widely used to treat type 2 diabetes mellitus. In this study, an untargeted urinary metabolomic analysis was performed to identify endogenous metabolites affected by glimepiride administration. Urine samples of twelve healthy male volunteers were collected before and after administration of 2 mg glimepiride. These samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and then subjected to multivariate data analysis including principal component analysis and orthogonal partial least squares discriminant analysis. Through this metabolomic profiling, we identified several endogenous metabolites such as adenosine 3', 5'-cyclic monophosphate (cAMP), quercetin, tyramine, and urocanic acid, which exhibit significant metabolomic changes between pre- and posturine samples. Among these, cAMP, which is known to be related to insulin secretion, was the most significantly altered metabolite following glimepiride administration. In addition, the pathway analysis showed that purine, tyrosine, and histidine metabolism was affected by pharmacological responses to glimepiride. Together, the results suggest that the pharmacometabolomic approach, based on LC-MS/MS, is useful in understanding the alterations in biochemical pathways associated with glimepiride action.

• BMB Reports
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• 제48권3호
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• pp.139-146
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• 2015

Adaptive brain function and synaptic plasticity rely on dynamic regulation of local proteome. One way for the neuron to introduce new proteins to the axon terminal is to transport those from the cell body, which had long been thought as the only source of axonal proteins. Another way, which is the topic of this review, is synthesizing proteins on site by local mRNA translation. Recent evidence indicates that the axon stores a reservoir of translationally silent mRNAs and regulates their expression solely by translational control. Different stimuli to axons, such as guidance cues, growth factors, and nerve injury, promote translation of selective mRNAs, a process required for the axon's ability to respond to these cues. One of the critical questions in the field of axonal protein synthesis is how mRNA-specific local translation is regulated by extracellular cues. Here, we review current experimental techniques that can be used to answer this question. Furthermore, we discuss how new technologies can help us understand what biological processes are regulated by axonal protein synthesis in vivo.

• The Korean Journal of Physiology and Pharmacology
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• 제20권1호
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• pp.63-67
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• 2016

Severe graft-versus-host disease (GVHD) is an often lethal complication of allogeneic hematopoietic stem cell transplantation (HSCT). The safety of clinical-grade mesenchymal stem cells (MSCs) has been validated, but mixed results have been obtained due to heterogeneity of the MSCs. In this phase I study, the safety of bone marrow-derived homogeneous clonal MSCs (cMSCs) isolated by a new subfractionation culturing method was evaluated. cMSCs were produced in a GMP facility and intravenously administered to patients who had refractory GVHD to standard treatment resulting after allogeneic HSCT for hematologic malignancies. After administration of a single dose ($1{\times}10^6cells/kg$), 11 patients were evaluated for cMSC treatment safety and efficacy. During the trial, nine patients had 85 total adverse events and the rate of serious adverse events was 27.3% (3/11 patients). The only one adverse drug reaction related to cMSC administration was grade 2 myalgia in one patient. Treatment response was observed in four patients: one with acute GVHD (partial response) and three with chronic GVHD. The other chronic patients maintained stable disease during the observation period. This study demonstrates single cMSC infusion to have an acceptable safety profile and promising efficacy, suggesting that we can proceed with the next stage of the clinical trial.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제24권6호
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• pp.546-554
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• 2021

Purpose: Malnutrition is a significant issue for pediatric patients with cancer. We sought to evaluate the effectiveness and complication rate of percutaneous endoscopic gastrostomy (PEG) placement in pediatric oncology patients. Methods: A retrospective chart review was performed on 49 pediatric oncology patients undergoing PEG placement at Johns Hopkins All Children's Hospital between 2000 and 2016. Demographic and clinical characteristics, complications, absolute neutrophil count at time of PEG placement and at time of complications, length of stay, and mortality were identified. Weight-for-age Z-scores were evaluated at time of- and six months post-PEG placement. Results: The overall mean weight-for-age Z-score improved by 0.73 (p<0.0001) from pre- (-1.11) to post- (-0.38) PEG placement. Improvement in Z-score was seen in patients who were malnourished at time of PEG placement (1.14, p<0.0001), but not in those who were not malnourished (0.32, p=0.197). Site infections were seen in 12 (24%), buried bumper syndrome in five (10%), and tube dislodgement in one (2%) patient. One patient (2%) with fever was treated for possible peritonitis. There were no cases of other major complications, including gastric perforation, gastrocolic fistula, clinically significant bleeding, or PEG-related death documented. Conclusion: Consistent with previous studies, our data suggests a relationship between site complications (superficial wound infection, buried bumper syndrome) and neutropenia. Additionally, PEG placement appears to be an effective modality for improving nutritional status in malnourished pediatric oncology patients. However, larger prospective studies with appropriate controls and adjustment for potential confounders are warranted to confirm these findings.

• Parasites, Hosts and Diseases
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• 제61권4호
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• pp.418-427
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• 2023

Toxoplasma gondii infections are primarily diagnosed by serological assays, whereas molecular and fluorescence-based techniques are garnering attention for their high sensitivity in detecting these infections. Nevertheless, each detection method has its limitations. The toxoplasmosis detection capabilities of most of the currently available methods have not been evaluated under identical experimental conditions. This study aimed to assess the diagnostic potential of enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), and immunofluorescence (IF) in BALB/c mice experimentally infected with various doses of T. gondii ME49. The detection of toxoplasmosis from sera and brain tissues was markedly enhanced in mice subjected to high infection doses (200 and 300 cysts) compared to those subjected to lower doses (10 and 50 cysts) for all the detection methods. Additionally, increased B1 gene expression levels and cyst sizes were observed in the brain tissues of the mice. Importantly, IHC, IF, and ELISA, but not RT-PCR, successfully detected T. gondii infections at the lowest infection dose (10 cysts) in the brain. These findings may prove beneficial while designing experimental methodologies for detecting T. gondii infections in mice.

• 한국의학물리학회지:의학물리
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• 제24권1호
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• pp.54-60
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• 2013

본 연구의 목적은 두경부암 환자에서 aid-pillow 사용에 따른 pitch와 yaw의 변화를 분석하고자 하였다. 두경부암 환자 총 14명을 선정하여 aid-pillow 미사용 그룹(without, n=7)과 사용 그룹(with, n=7)으로 나누어 비교 분석하였다. 총 333회의 MVCT 영상을 이용하여 미사용 그룹(153 image set)과 사용 그룹(180 image set) 각각 종축 일치도(translational adjustments (lateral, longitudinal, vertical))와 회전축 일치도(rotational adjustments (pitch, roll, yaw))를 구하였다. Pitch의 변화 즉, 편차는 미사용 그룹 $0.12^{\circ}$이고, 사용 그룹 $0.09^{\circ}$였다. 그리고, yaw는 미사용 그룹 $0.47^{\circ}$이고, 사용 그룹 $0.17^{\circ}$였다. 전반적으로 사용 그룹이 미사용 그룹에 비해 편차가 작았다. 따라서, 토모테라피를 이용하여 두경부암 방사선치료 시 aid-pillow를 사용하여 pitch와 yaw의 변화를 줄임으로써, 치료의 재현성을 높일 수 있을 것으로 사료된다.

• Journal of Gastric Cancer
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• 제21권4호
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• pp.368-378
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• 2021

Purpose: When patients with early gastric cancer (EGC) undergo non-curative endoscopic submucosal dissection requiring gastrectomy (NC-ESD-RG), additional medical resources and expenses are required for surgery. To reduce this burden, predictive model for NC-ESD-RG is required. Materials and Methods: Data from 2,997 patients undergoing ESD for 3,127 forceps biopsy-proven differentiated-type EGCs (2,345 and 782 in training and validation sets, respectively) were reviewed. Using the training set, the logistic stepwise regression analysis determined the independent predictors of NC-ESD-RG (NC-ESD other than cases with lateral resection margin involvement or piecemeal resection as the only non-curative factor). Using these predictors, a risk-scoring system for predicting NC-ESD-RG was developed. Performance of the predictive model was examined internally with the validation set. Results: Rate of NC-ESD-RG was 17.3%. Independent pre-ESD predictors for NC-ESD-RG included moderately differentiated or papillary EGC, large tumor size, proximal tumor location, lesion at greater curvature, elevated or depressed morphology, and presence of ulcers. A risk-score was assigned to each predictor of NC-ESD-RG. The area under the receiver operating characteristic curve for predicting NC-ESD-RG was 0.672 in both training and validation sets. A risk-score of 5 points was the optimal cut-off value for predicting NC-ESD-RG, and the overall accuracy was 72.7%. As the total risk score increased, the predicted risk for NC-ESD-RG increased from 3.8% to 72.6%. Conclusions: We developed and validated a risk-scoring system for predicting NC-ESD-RG based on pre-ESD variables. Our risk-scoring system can facilitate informed consent and decision-making for preoperative treatment selection between ESD and surgery in patients with EGC.

• KSBB Journal
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• 제16권1호
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• pp.1-10
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• 2001

Escherichia coli has been used as an expression work horse for foreign genes. This article summarized recent development in genetic engineering techniques for overproduction of medical proteins and industrial enzymes. Special emphasis was placed upon research activities concerning folding and refolding of inclusion bodies at genetic and fermentation levels. Plasmid and mRNA stabilization, development of strong inducible promoters, modification of translational elements and reduction of rpoteolytic degradation were carried out to elevate an expression level of a target protein. Optimization of culture conditions, improvement of denaturation and renaturation steps and coexpression of molecular chaperones or foldase were accomplished to produce active proteins in soluble form. Fusion protein systems with selective separation and surface display technology were also performed in an effort to make the E. coli expression system more effective and versatile.

• 대한의용생체공학회:의공학회지
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• 제25권4호
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• pp.301-307
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• 2004

보행 중 각 관절의 모멘트를 계산하기 위한 역동역학 모델을 개발하였다. 모델은 1개의 상체와 3개의 체절로 하지를 구성하였고 3개의 병진 조인트와 12개의 회전조인트로 각 체절을 연결하고 뉴턴-오일러 방법으로 역동역학 해를 구하였다. 입력자료로서의 기구학적 사료는 3차원 동작분석 시스템에서 추출하였고 외력으로서 지면 반발력은 동기화한 힘측정판에서 구했다. 개발된 모델을 이용하여 비대칭 모델이나 질량중심의 이동을 포함한 해석 등 다양한 인체운동 해석이 가능하다.