• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
• /
• pp.77-77
• /
• 2003

Sepsis remains common surgical problems with high morbidity and mortality despite improvement in the management for septic patient. Although hepatocellular dysfunction occurs during sepsis, the mechanism responsible for this remains unclear. In sepsis, a state of severe oxidative stress is encountered, with host endogenous antioxidant defenses overcome. Therefore, the aim of this study was to determine the effect of a-tocopherol (AT) vasoregulatory gene expression during polymicrobial sepsis. Rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP). AT (15 mg/kg) was intraperitonealy injected for 3 days prior to CLP. Blood samples were taken 24 h after CLP for measurement of the extent of hepatocellular damage. Liver samples were taken for RT-PCR analysis of mRNA for genes of interest: endothelin-l (ET-l), its receptors $ET_{A}$ and $ET_{B}$, nitric oxide synthases (iNOS and eNOS), cyclooxygenase-2 (COX -2), heme oxygenase-l (HO-l), and tumor necrosis factor-$\alpha$ (TNF-$\alpha$). The activities of serum alanine aminotransferase and lipid peroxidation level were significantly increased; an increase which was prevented by AT pretreatment. CLP significantly increased the mRNA levels of ET-1 and $ET_{B}$; an increase that was prevented by AT pretreatment. However, the level of $ET_{A}$ mRNA significantly decreased after CLP; a decrease that was not prevented by AT pretreatment. There were significant increases in the mRNA expression of iNOS, HO-l and COX -2 in CLP groups. This increase was prevented by AT pretreatment. The expression of eNOS and TNF-$\alpha$ mRNA significantly increased in CLP, which was not prevented by AT pretreatment. Our findings suggest that there was an imbalanced vasoregulatory gene expression in sepsis, and AT ameliorates this change through its free radical scavenging activity.

• 대한기계학회논문집A
• /
• 제40권10호
• /
• pp.851-856
• /
• 2016

최근 미세가공기술이 발전함에 따라 생체분해성 소재 기반의 미소바늘 혹은 미소바늘 주사기에 대한 연구가 각광을 받고 있다. 일반적으로 생체분해성 소재는 기계적 강도가 낮아 생체분해성 소재 기반의 미소바늘은 피부조직 관통 시 구부려지거나 파손되는 문제점을 가지고 있다. 본 연구에서는 기계적 강도가 향상된 생체적합성 소재를 새로이 합성하는 대신에 미소바늘 삽입 전 피부조직에 1축 혹은 등2축 초기변형률을 가해 미소바늘의 피부조직 관통력을 감소시키는 방법에 대해 살펴본다. 실험에서는 1축 혹은 등 2축 초기변형률을 가해 준 돼지 피부조직에 미소바늘을 삽입시키면서 힘-시간 데이터를 획득함으로써 초기변형률에 의한 미소바늘의 관통력 변화를 측정하였다. 본 연구를 통해 미소바늘의 피부조직 관통력은 피부조직에 초기변형률을 가해주는 방법으로 감소시킬 수 있음을 확인하였다.

• Journal of Oral Medicine and Pain
• /
• 제21권2호
• /
• pp.225-242
• /
• 1996

The author studied to determine the sex and age of 8 ancient human skeletal remains, which had excavated from ancient tombs located in Yeanri, Kimhae. Some kinds of personal identification methods their skulls and teeth were used for this study and the results were obtained as follows : 1. Sex determination was possible in ancient teeth from 4th to 5th century, using detection of X-Y homologous amelogenin gene by polymerase chain reaction. 2. DNA analysis proved that the materials examined were all male, but which always did not coincide with the results from other methods for sex determination including comparison of sexual differentiation of cranium and teeth and use of discriminant functions in the dental measurement. 3. There was little difference of the estimated ages between the methods by regression of pulp cavity and attrition in teeth. The ages from these two methods always did not coincide with ones from evaluation closure of cranial and palatal sutures. 4. Sex and age of the materials were determined as follows ; $\cdot$ Y9 was estimated to be male in early sixties. $\cdot$ Yl2 was estimated to be male in late twenties to early thirties. $\cdot$ Y37 was estimated to be male in early forties. $\cdot$ Y70 was estimated to be male in early sixties. $\cdot$ Y87 was estimated to be male in late forties. $\cdot$ Y109 was estimated to be male in early forties. $\cdot$ Yl29 was estimated to be male in late thirties to early forties. $\cdot$ Yl42 was estimated to be male in late fifties to early sixties.

• Journal of Dental Anesthesia and Pain Medicine
• /
• 제17권3호
• /
• pp.163-181
• /
• 2017

In the field of orofacial surgery, a red blood cell transfusion (RBCT) is occasionally required during double jaw and oral cancer surgery. However, the question remains whether the effect of RBCT during the perioperative period is beneficial or harmful. The answer to this question remains challenging. In the field of orofacial surgery, transfusion is performed for the purpose of oxygen transfer to hypoxic tissues and plasma volume expansion when there is bleeding. However, there are various risks, such as infectious complications (viral and bacterial), transfusion-related acute lung injury, ABO and non-ABO associated hemolytic transfusion reactions, febrile non-hemolytic transfusion reactions, transfusion associated graft-versus-host disease, transfusion associated circulatory overload, and hypersensitivity transfusion reaction including anaphylaxis and transfusion-related immune-modulation. Many studies and guidelines have suggested RBCT is considered when hemoglobin levels recorded are 7 g/dL for general patients and 8-9 g/dL for patients with cardiovascular disease or hemodynamically unstable patients. However, RBCT is occasionally an essential treatment during surgeries and it is often required in emergency cases. We need to comprehensively consider postoperative bleeding, different clinical situations, the level of intra- and postoperative patient monitoring, and various problems that may arise from a transfusion, in the perspective of patient safety. Since orofacial surgery has an especially high risk of bleeding due to the complex structures involved and the extensive vascular distribution, measures to prevent bleeding should be taken and the conditions for a transfusion should be optimized and appropriate in order to promote patient safety.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
• /
• pp.118-118
• /
• 2008

The oxide CMP has been applied to interlayer dielectric(ILD) and shallow trench isolation (STI) in chip fabrication. Recently the slurry used in oxide CMP being changed from silica slurry to ceria (cerium dioxide) slurry particularly in STI CMP, because the material selectivity of ceria slurry is better than material selectivity of silica slurry. Moreover, the ceria slurry has good a planarization efficiency, compared with silica slurry. However ceria abrasives make a material removal rate too high at the region of wafer center. Then we focuses on why profile of material removal rate is convex. The material removal rate sharply increased to 3216 $\AA$/min by $4^{th}$ run without conditioning. After $4^{th}$ run, material removal rate converged. Furthermore, profile became more convex during 12 run. And average material removal rate decreased when conditioning process is added to end of CMP process. This is due to polishing mechanism of ceria. Then the ceria abrasive remains at the pad, in particular remains more at wafer center contacted region of pad. The field emission scanning electron microscopy (FE-SEM) images showed that the pad sample in the wafer center region has a more ceria abrasive than in wafer outer region. The energy dispersive X-ray spectrometer (EDX) verified the result that ceria abrasive is deposited and more at the region of wafer center. Therefore, this result may be expected as ceria abrasives on pad surface causing the convex profile of material removal rate.

• Molecules and Cells
• /
• 제46권10호
• /
• pp.611-626
• /
• 2023

Acute myeloid leukemia (AML) is a heterogeneous disease caused by distinctive mutations in individual patients; therefore, each patient may display different cell-type compositions. Although most patients with AML achieve complete remission (CR) through intensive chemotherapy, the likelihood of relapse remains high. Several studies have attempted to characterize the genetic and cellular heterogeneity of AML; however, our understanding of the cellular heterogeneity of AML remains limited. In this study, we performed single-cell RNA sequencing (scRNAseq) of bone marrow-derived mononuclear cells obtained from same patients at different AML stages (diagnosis, CR, and relapse). We found that hematopoietic stem cells (HSCs) at diagnosis were abnormal compared to normal HSCs. By improving the detection of the DNMT3A R882 mutation with targeted scRNAseq, we identified that DNMT3A-mutant cells that mainly remained were granulocyte-monocyte progenitors (GMPs) or lymphoid-primed multipotential progenitors (LMPPs) from CR to relapse and that DNMT3A-mutant cells have gene signatures related to AML and leukemic cells. Copy number variation analysis at the single-cell level indicated that the cell type that possesses DNMT3A mutations is an important factor in AML relapse and that GMP and LMPP cells can affect relapse in patients with AML. This study advances our understanding of the role of DNMT3A in AML relapse and our approach can be applied to predict treatment outcomes.

• 한국암반공학회:학술대회논문집
• /
• 한국암반공학회 2007년도 춘계학술발표회 논문집
• /
• pp.130-139
• /
• 2007

We have carried out numerical compression experiments to estimate the mechanical properties (Mohr-Coulomb and elastic) of corestone-bearing saprolites in Beolgyo area. The studied saprolite, consisting of mechanically much stronger corestone and weaker matrix, is a weathering product of the Precambrian granitic gneiss in the Youngnam massif. Since the saprolite consists of larger corestones with diameter up to 2m, it is impossible to directly measure the mechanical properties by physical experiments. We have measured the mechanical properties of corestone and matrix from naturally occurring saprolite and have used them as a reference for our numerical model. Then, we mixed each material and carried out biaxial compression tests while varying the volume percentage of corestones from 0 to 57%. We found that both cohesion and internal friction angle increase with the volume percentage of corestones while elastic modulus remains constant. We found the results from numerical experiments are in contradiction to what is known from physical experiments using artificial saprolites. This may be due to a possibility that the sharp and discrete nature of interface between corestone and matrix in physical experiments differs from the gradual interfacial nature in numerical modelling and natural saprolites.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2007년도 추계학술대회논문집
• /
• pp.1276-1279
• /
• 2007

The main objectives of the Load/Unload are no slider-disk contact and no media damage. But, it remains unsolved technical problems on the unloading process. While the slider climbs up the ramp at the outer edge of the disk, the possibility of the slider-disk contact by lift-off force and rebound of the slider increases. Keeping in mind of these points, to prevent the slider-disk contact, we apply the disk bump on disk outer edge proceeding unload. First, referring to the simulation results, we select the optimal bump shapes to improve unload performance by unload analysis. Second, the disk bump is mechanically manufactured by pressing disk surface using tungsten tips. The bumps are variously processed by changing pressing pressure of tungsten tips. After confirming bump shape by nano-scanner, the optimal bump shape is applied to experimental unload process. Through this experiment, it is conformed that the unload performance was improved by using the optimal disk bump to prevent the slider-disk contact.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2007년도 춘계학술대회논문집
• /
• pp.833-836
• /
• 2007

Load/Unload technology has more benefits than the conventional CSS technology. However, it remains unsolved technical problem on the unloading process. While the slider climbs up the ramp at the outer edge of the disk, the possibility of the slider-disk contact by lift-off force and rebound of the slider increases. This paper focuses on no slider-disk contact. To prevent the slider-disk contact, we apply the disk bump on disk outer edge proceeding unload. Firstly, in the simulation, the bump dimension is determined by changing bump design parameters. Secondly, dynamic stability of slider have to be checked on disk bump before unload analysis, and unload analysis is performed by applying stable bump shapes to unload simulation. Thirdly, we select optimal bump shape to improve unload performance by unload analysis. Finally, in the experiment, the disk bump is mechanically manufactured by pressing disk surface using diamond tip. That is variously processed by changing pressing pressure. After confirming bump shape by nano-scanner, proper bump shape is applied to real experimental unload process. Through this investigation, we propose the optimal bump design to prevent the slider-disk contact, and then we can realize improved unloading performance.

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2003년도 추계학술대회
• /
• pp.68-83
• /
• 2003

Welders working in a confined space, like in the shipbuilding industry, are at risk of being exposed to high concentrations of welding fumes and developing pneumoconiosis or other welding-fume exposure related diseases. Among such diseases, manganism resulting from welding-fume exposure remains a controversial issue, as the movement of manganese into specific brain regions has not been clearly established.(omitted)