• 한국가축번식학회지
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• 제17권3호
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• pp.233-242
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• 1993

The effects of in vitro maturation and sperm treatment condition on the in vitro fertilization (IVF) and developmental capacity of bovine oocytes were investigated and the development of embryos was compared under the 2 different co-culture system, with GC or BOEC. The cultured embryo to 16 cell or morula wre transferred into recipients or frozen by 2 different freezing method. The results obtained were summarized as follows; 1. In vitro maturation rates of vovine follicular oocytes cultrued in TCM199 with 10% FCS or ECS were 64.0% and 72.7%, but the case of addition of 10% FCS or ECS to TCM199 co-cultured with granulosa cells were 81.3% and 84.0%, respectively. IVM rate of three TCM199 added to granulosa cells was higher than that of media without granulosa cells. 2. When bovine follicular oocytes were matured in TCM199 with 10% FCS and GC and then fertilized in vitro by sperm treated with caffeine, embryo developments of bovine oocytes co-cultured with BOEC were 38.4% and 51.4%, respectively. But those of bovine oocytes co-cultured with GC were 52.2% by sperm treated with caffeine-heparin. 3. Cleavage rates of bovine oocytes cultured with 10% FCS alone and fertilized in vitro by sperm treated with caffeine-heparin was 33.0%. 4. When bovine follicular oocytes were matured in TCM199 with 10% FCS and GC, embryo developments of bovine ooctyes co-cultured with BOEC of GC were 46.0% and 50.2%, respectively. 5. When bovine follicular oocytes were matured in TCM199 with 10% ECS and GC, embryo developments co-cultured with BOEC or GC were 45.2% and 51.4%, respectively. 6. When Korean Native cow's follicular oocytes matured in TCM199 with 10% FCS and GC, embryo developed co-cultured with BOEC or GC were 45.2% and 51.4%, respectively. 6. When Korean Native cow's follicular oocytes matured in TCM199 with 10% FCS and GC, embryo developments of the bovine oocyte co-cultured with BOEC and GC were 41.8% and 60.1%. But with FCS 10% those of the bovine oocytes co-cultured with BOEC and GC were 42.0% and 48.4%, respectively. 7. When Holstein's follicular oocytes were matured in TCM199 with 10% ECS and GC, embryo developments fo the bovine oocytes co-cultured with BOEC and GC were 50.0% and 57.7%, but with ECS 10% those of the bovine oocytes co-cultured with BOEC and GC were 52.2% and 56.5%, respectively. 8. The viability of frozen-thawed embryos ranged from 60~80% and those of frozen-thawed embryos from vitrification was lower than that from conventional metiod. 9. The selected fresh embryos were transferred nonsurgically to 7 recipients but did not result in pregnancy.

• 생명과학회지
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• 제15권1호
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• pp.136-140
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• 2005

다양한 라세믹 에폭사이드 기질에 대한 입체선택적 가수분해 반응을 촉매하는 epoxide hydrolase 활성을 측정할 수 있는 미생물 세포 기반의 자외선 활성 분석법을 최적화하였다. 2.5 mg/ml의 세포 농도에서도 비교적 쉽게 흡광도 변화량을 인식할 수 있는 흡광도 범위인 0.5 이상을 얻을 수 있고, 반응 동력학 분석에도 응용할 수 있었다. 기존의 GC, HPLC 분석 법 보다 분석 시간을 줄일 수 있으며, 효소를 별도로 분리$\cdot$정제하지 않고 미생물 세포 자체의 epoxide hydrolase활성 분석이 가능하므로 상업적 특성이 우수한 epoxide hydrolase을 가진 미생물을 효율적으로 선별하는데 응용될 수 있을 것으로 기대된다.

• 분석과학
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• 제22권3호
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• pp.191-200
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• 2009

이 연구는 소형방출챔버와 방출셀을 이용한 총휘발성유기화합물(TVOC) 방출시험결과의 상관성을 규명하여 방출셀을 이용한 액상 건축자재 오염물질 방출시험 방법을 정립하고 활용방안을 제시하기 위한 기초 자료를 확보하고자 수행되었다. 소형방출챔버와 방출셀을 이용한 액상 건축자재 방출시험을 실시하기 위해 방출시험 적합성 여부를 판단하고 최적조건을 확립하기 위하여 방출시험장치, 분석기기에 대한 성능평가를 실시하였다. 방출시험 장치인 소형방출챔버와 방출셀의 배경농도 청정도, 기밀도, 회수율, 분석장치인 열탈착장치 회수율 및 GC/MS 기기재현성, 방법검출한계(MDL) 등을 평가한 결과 방출시험장치와 분석기기의 조건은 안정적이고 재현성과 감도가 양호하여 액상 건축자재에서 방출되는 오염물질에 대한 측정 분석조건이 최적화되었음을 확인할 수 있었다. 페인트, 접착제, 실란트로 구성된 40개의 액상 건축자재를 대상으로 소형방출챔버와 방출셀을 이용하여 오염물질 방출시험을 실시한 결과 방출되는 총휘발성유기화합물의 농도는 소형 방출챔버와 방출셀에서 모두 대수정규분포(log normal distribution)하였으며 시험방법차이에 따른 방출량 분포의 차이는 크지 않았다. 또한 방출셀을 이용하여 오염물질 방출시험을 실시하였을 때, 소형방출챔버를 이용하였을 때보다 약 1.35~1.41배 높은 방출량을 나타내었으며 상관계수(r)가 약 0.91~0.97의 범위를 보여 높은 상관성이 있는 것으로 확인되었다.

• Journal of Gastric Cancer
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• 제23권1호
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• pp.207-223
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• 2023

Gastric cancer (GC) is the fourth leading cause of cancer-related deaths worldwide. Under the standard of care, patients with advanced GC (AGC) have a median survival time of approximately 12-15 months. With the emergence of immunotherapy as a key therapeutic strategy in medical oncology, relevant changes are expected in the systemic treatment of GC. In the phase III ATTRACTION-2 trial, nivolumab, a monoclonal anti-programmed cell death 1 (PD-1) antibody, as a third- or later-line treatment improved overall survival (OS) compared with placebo in patients with AGC. Furthermore, nivolumab in combination with 5-fluorouracil and platinum as a first-line treatment improved OS in patients with human epidermal growth factor receptor-2 (HER2)-negative AGC in the global phase III CheckMate-649 study. Another anti-PD-1 antibody, pembrolizumab, in combination with trastuzumab and cytotoxic chemotherapy as a first-line treatment, significantly improved the overall response rate in patients with HER2-positive AGC. Therefore, immune checkpoint inhibitors (ICIs) are essential components of the current treatment of GC. Subsequent treatments after ICI combination therapy, such as ICI rechallenge or combination therapy with agents having other modes of action, are being actively investigated to date. On the basis of the success of immunotherapy in the treatment of AGC, various clinical trials are underway to apply this therapeutic strategy in the perioperative and postoperative settings for patients with early GC. This review describes recent progress in immunotherapy and potential immunotherapy biomarkers for GC.

• IMMUNE NETWORK
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• 제14권1호
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• pp.21-29
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• 2014

Follicular helper T ($T_{FH}$) cells are recently highlighted as their crucial role for humoral immunity to infection as well as their abnormal control to induce autoimmune disease. During an infection, na$\ddot{i}$ve T cells are differentiating into $T_{FH}$ cells which mediate memory B cells and long-lived plasma cells in germinal center (GC). $T_{FH}$ cells are characterized by their expression of master regulator, Bcl-6, and chemokine receptor, CXCR5, which are essential for the migration of T cells into the B cell follicle. Within the follicle, crosstalk occurs between B cells and $T_{FH}$ cells, leading to class switch recombination and affinity maturation. Various signaling molecules, including cytokines, surface molecules, and transcription factors are involved in $T_{FH}$ cell differentiation. IL-6 and IL-21 cytokine-mediated STAT signaling pathways, including STAT1 and STAT3, are crucial for inducing Bcl-6 expression and $T_{FH}$ cell differentiation. $T_{FH}$ cells express important surface molecules such as ICOS, PD-1, IL-21, BTLA, SAP and CD40L for mediating the interaction between T and B cells. Recently, two types of microRNA (miRNA) were found to be involved in the regulation of $T_{FH}$ cells. The miR-17-92 cluster induces Bcl-6 and $T_{FH}$ cell differentiation, whereas miR-10a negatively regulates Bcl-6 expression in T cells. In addition, follicular regulatory T ($T_{FR}$) cells are studied as thymus-derived $CXCR5^+PD-1^+Foxp3^+\;T_{reg}$ cells that play a significant role in limiting the GC response. Regulation of $T_{FH}$ cell differentiation and the GC reaction via miRNA and $T_{FR}$ cells could be important regulatory mechanisms for maintaining immune tolerance and preventing autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Here, we review recent studies on the various factors that affect $T_{FH}$ cell differentiation, and the role of $T_{FH}$ cells in autoimmune diseases.

• Restorative Dentistry and Endodontics
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• 제21권1호
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• pp.403-424
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• 1996

Cell culture methods have been used to assess the cytotoxicity of dental materials. Different paramaters are used to monitor cytotoxic effects. But it is difficult to compare each investigator's results with different methods. The objective of this study was to investigate cytotoxic effect of several retrograde filling materials according to cell lines and assay methods. Cytotoxicity of Bestalloy (Dogmyung, Korea), Prisma APH(Densply International Inc., U.S.A.), Clearfil FII (Kuraray Co., Japan), Fuji II (GC Co., Japan), Fuji II LC (GC Co., Japan) and IRM (Densply Co., U.S.A.) on L929, 3T3 and KB permanent cell lines was measured. Radiochromium, Lactate dehydrogenase (LDH) release method and colorimetric assays, namely neutral red (NR) and MTT were used. Each material was mixed according to the manufacturer's instruction. They were tested as solid and extracted state. Cell culture media were added to each mixed or solid materials then the solution was collected and used as extract solutions. Solid Fuji II showed mild cytotoxicity on three cell lines using radiochromium release method. There was no difference in cytotoxicity of extract solution group using radiochromium release method. In colorimetric assay immediate Fuji II group and all the IRM groups showed severe cytotoxic effect. Difference in cyctotoxicity was due to rather kinds of cell lines than assay methods. Solid Fuji II and IRM showed mild cytotoxicity on three cell lines. But extract solutions had different cytotoxic effect according to cell lines using LDH release assay. Light-cured glass ionomer had mild to moderate degree of cytotoxicity on three cell lines. Cytotoxicity was affected by specimen prepaton. Susceptibility of each cell ines were also affected by assay emthods. It was suggested that cytotoxicity study using only one cell line and/or assay method might not accurately reflect the real toxic nature of dental biomaterials.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Signal transduction in Toxicology
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• pp.89-93
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• 2001

All that is presently known about the actions of 8-hydroxyguanine (8-oxoguanine; oh$^{8}$ Gua) in DNA is that it harms genetic integrity. This is even speculation based upon scattered in vitro experimental data such as the mismatch of oh$^{8}$ Gua with A in stead of C and the GC longrightarrow TA transversion observed in the DNA polymerase reaction using an oh$^{8}$ Gua containing oligonucleotide.(omitted)

• Fisheries and Aquatic Sciences
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• 제7권1호
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• pp.34-38
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• 2004

The heterotrophic production method for Tetraselmis suecica, a suggested alternative to photoautotrophic one in the economic sense, was studied in terms of cell growth and sterolic property. The alga in the 10 mM organic carbon (glucose) manifested cell growth. However, the alga produced by the heterotrophic method showed a unique property of sterol determined with an aid of GC and GC-MS. The photoautotrophic control T. suecica contained 6 detectable sterol species: $cholesta-5,\;22-dien-3\beta-o1$, $ergost-5-en-3\beta-o1$, cholest-5-en-3\beta-o1$, $24-methyl-cholesta-5,\;22-dien-3\beta-o1$, $24-methylcholesta-5,\;24-dien-3\beta-o1$, $24-ethylchlolesta-5,\;24-dien-3\beta­o1$, $24-methylcholesta-5-en-3\beta-o1$, and $24-ethylchlolesta-5en-3\beta-o1$. We discuss the sterolic properties of the alga along the heterotrophic progress, particularly focusing on the availability of the method in the aquaculture of bivalves which normally need sterols as a dietary source.

• Asian-Australasian Journal of Animal Sciences
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• 제19권11호
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• pp.1574-1579
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• 2006

This study was performed to determine the developmental potentials of nuclear transfer (NT) embryos using life-span extended cells transfected with a foreign gene as donor cells. A life-span extended bovine embryonic fibroblast cell line was transfected with an expression vector in which the human type II collagen (BOMAR) and ear fibroblasts were used as a donor cell. Cytogenetic analysis was performed to analyze the chromosomal abnormality of donor cells. The fusion rate of 1.8 kV/cm for $15{\mu}sec$ given twice was significantly higher than that of other groups (p<0.05) and the embryos lysed were significantly higher after 1.8 kV/cm for $20{\mu}sec$ given once compared to other groups (p<0.01). The blastocyst development in the ear cell group was statistically significant compared to both BOMAR groups (p<0.01). Both BOMAR groups cultured more than 40 passages (>40 passages) had a lower number of chromosomes; however, fresh granulosa cell (GC) and BOMAR groups cultured less than 20 passages had normal chromosome numbers. Both >40 passages BOMAR groups had numerous obscure debris in metaphase spreads. The transfected foreign gene was expressed in all BOMAR groups, but not in the GC group. Based on these results, the lower developmental potential of NT embryos using life-span extended donor cells transfected with a foreign gene might be a cause of chromosomal abnormality in donor cells.

• 대한본초학회지
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• 제22권4호
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• pp.81-86
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• 2007

Objectives : The purpose of this study is to examine the antioxidant activity in the germ cells of the extract of Rehmanniae Radix Preparat (RR). Methods : The extract was studied for diphenyl-picryl-hydrazyl (DPPH) radical scavenging activity, GC-1 cell viability by a modified MTT assay, the effects on H2O2-induced cytotoxicity by MTT assay and lipid peroixidation by malondialdehyde (MDA) formation, respectively. Results : The results showed that the extract scavenged DPPH radical in a dose-dependent manner by up to 43.1%. The extract at concentrations of 100 ${\mu}g/ml$ showed peak level of 136.5% in growth of GC-1 cell. The hydrogen peroxide-induced cytotoxicity was blocked by the extract at concentrations of 10, 50 and 100 ${\mu}g/ml$. The extract (50 and 100 ${\mu}g/ml$) also displayed a dose-dependent reduction of MDA formation on hydrogen peroxide-induced lipid peroxidation. Conclusions : In conclusion, the extract of Rehmanniae Radix Preparat has strong antioxidant activity.