• 약학회지
• /
• 제48권2호
• /
• pp.153-158
• /
• 2004

Paecilomyces tenuipes is one of the famous Chinese medicinal entomopathogenic fungi that parasite in the lavae of silkworm. A cytotoxic compound, 4$\beta$-acetoxyscirpendiol (ASD) was isolated from a methanolic extracts of Paecilomyces tenuipes. The ASD compound belongs to scirpenol subfamily of trichothecene mycotoxin. In a continuation of the elucidation of the mechanism of ASD, we report here the evidences of induction of apoptosis by ASD in human Jurkat T cell line. In MTT reduction assay for monitoring cell viability, ASD showed strong toxicity. The 50 percent inhibitory concentrations of ASD against human T lymphoid Jurkat cell was 59.5 ng/$m\ell$. Phosphatidylserine externalization was increased by ASD at 3 and 6 hrs when compared with that of 6 hrs in the cell line showing in a time-dependent manner. When whole lysates of cells treated with ASD were subjected to western blot assay, 113 kDa poly(ADP-ribose) polymerase (PARP) was significantly cleaved to 89 kDa fragment. Time-dependent DNA fragmentation was also observed when Jurkat T cells were treated with ASD at 100 ng/$m\ell$ for 6 hrs and 18 hrs at the ratios of 8.5% and 15.0%, respectively. From these data, Jurkat T lymphocytes treated with ASD from Paecilomyces tenuipes underwent typical cascades of apoptotic cell death.

• 한국임상수의학회지
• /
• 제18권4호
• /
• pp.358-362
• /
• 2001

Brain dead (BD) patients remain the largest source of solid organs for transplantation. BD has shown to decrease graft function and survival in rodent models. The aim of this study was to evaluate how brain death affects graft viability in the donor and kidney tolerance to cold preservation as assessed by survival in a canine transplantation. 13 Beagle dogs were used for the study. Brain death was induced by the sudden inflation of a subdural balloon catheter with continuous monitoring of arterial blood pressure and eletroencephalographic activity (n=3). Sixteen hours after conformation of brain death, kidney graft were retrieved (n=6). Non-BD donors served as controls (n=4). All kidneys were flushed with University of Wisconsin (UW) solution and preserved for 24 hours at 4$^{\circ}C$ before transplantation. Recipient survival rates, serum creatinine level were analyzed. Brain death induced the well-known Cushing reaction with a severe increase in blood pressure and tachycardia. Thereafter, cardiac function returned progressively to baseline within 8 hours and remained stable until the end of the experiment. All of dogs in both group transplanted were survived until 7 days (100%), and the kidneys showed functional early rejection at 8.3$\pm$0.5 days and 8.5$\pm$0.5 days after transplantation, in BD and allograft group, respectively. BD kidneys were functionally similar to control kidneys for 7 days after transplantated. Brain death has no deleterious effect on preservation injury and survival of dog kidney transplantation, although it induces changes in hemodynamic parameters. This study reveals that kidneys from BD donors do not exhibit more ischemia reperfusion injury, and support good early function and survival.

• Molecules and Cells
• /
• 제22권1호
• /
• pp.21-29
• /
• 2006

The aim of this study was to determine if hydrogen peroxide ($H_2O_2$) generated by glucose oxidase (GO) induces apoptosis or necrosis of BJAB cells and which radical is the direct mediator of cell death. We found that GO produced $H_2O_2$ continuously in low concentrations, similar to in vivo conditions, and decreased proliferation and cell viability in a dose-dependent manner. The GO-mediated cytotoxicity resulted from apoptosis, and was confirmed by monitoring the cells after H33342/Annexin V/propidium iodide staining. Decreases of mitochondrial membrane potential and intracellular glutathione level were found to be critical events in the $H_2O_2$-mediated apoptosis. Additional experiments revealed that $H_2O_2$ exerted its apoptotic action through the formation of hydroxyl radicals via the Fenton rather than the Haber-Weiss reaction. Moreover, intracellular redox-active iron, but not copper, participated in the $H_2O_2$-mediated apoptosis.

• 한국염색가공학회:학술대회논문집
• /
• 한국염색가공학회 2011년도 제45차 학술발표회
• /
• pp.41-41
• /
• 2011

The aims of this study were to examine the efficacy of phytochemicals of Rumex crispus as anti-oxidant and anti-browning agent. The bioactive properties of Rumex crispus as natural colorants were studied by total phenolic contents, DPPH radical scavenging, ABTS radical scavenging,lipid peroxidation, cell viability, singlet oxygen quenching and photoprotection effect. Among all of the results ($IC_{50}$: the concentration of various extracts required to exert 50% reducing effect), the higher activity of the extract was found in the ethyl acetate and butanol extracts. Anti-browning activity was evaluated by monitoring the change $L^*$, $a^*$, $b^*$ values and total color differences(${\Delta}E$). It was found that ethyl acetate and butanol extracts effectively inhibited browning in apple juice at a concentration below 0.3 mg/ml. Rumex crispus extracts used natural colorants could be of good resources as anti-oxidant and anti-browning agents. The results suggest that our study may contribute to the development of natural and functional materials with potential application to reduce oxidative damage.

• 센서학회지
• /
• 제32권6호
• /
• pp.352-356
• /
• 2023

The integration of bioelectronic devices with the skin is a promising strategy for personalized healthcare monitoring and diagnostics. On-skin bioelectrodes hold great potential for the real-time tracking of physiological parameters. However, persistent challenges of stability and reliability have instigated exploration beyond conventional noble metals. This study focuses on the ionic passivation and oxidation dynamics of copper-based on-skin thin-film bioelectrodes. Through parylene chemical vapor deposition, we harness a controlled thin film of parylene insulation to counter the intrinsic susceptibility of copper to oxidation in the ionic environment. The results represent the relationship among the parylene insulation thickness, copper oxidation, and electrode impedance over temporal intervals. Comparative analyses indicate that the short-term stability of the copper electrode is comparable to that of the gold electrode. Therefore, we propose a cost-effective strategy for fabricating copper-based on-skin bioelectrodes by introducing enhanced ionic stability within a discernible operational timeframe. This study enriches our understanding of on-skin bioelectronics and affordable material choices for practical use in wearable healthcare devices.

• 자원리싸이클링
• /
• 제33권2호
• /
• pp.16-23
• /
• 2024

해수나 염수에서 마그네슘을 추출하는 전해 반응은 마그네슘 이온을 주로 수산화마그네슘 형태로 마그네슘을 침전-회수하는 기술로, 양이온교환막, 음이온교환막, 전기투석, 비막 방식 등으로 분류된다. 최근 연구는 마그네슘 함유 해수나 염수를 사용하여 마그네슘의 회수 효율성 및 선택성 증진에 집중되며, 향후 일반 해수를 사용할 경우에도 효과적인 마그네슘 회수가 기대된다. 향후에는, 스케일업 시스템의 장기운전을 통해 마그네슘 및 다양한 유가물질에 대한 선택적 고효율 회수의 최적화와 더불어 경제성 및 환경성을 증진하는 것이 중요하다. 함께 막의 수명 및 교체주기를 고려하여 운전비용을 현실적으로 산정해야 하며, 다양한 인자에 대한 모니터링 데이터를 기반으로 상세하고 실용적인 공정 모델이 필요하다.

• 지구물리와물리탐사
• /
• 제9권1호
• /
• pp.1-9
• /
• 2006

포획된 $CO_2$ 의 지질학적 저장은 기후 보호를 위한 온실가스 방출 감소의 새로운 방법이나, 유체의 땅속 주입과 관련된 기존의 확립된 기술에 근거하고 있다. 이 기술에 대해 관심있는 지층 구조는 현재 가행 중이거나 고갈된 석유, 가스층, 그리고 심부 염수 대수층이다. 저장 능력에 대한 예측은 지층구조내에서 $CO_2$의 거동 모델들에 의해 좌우되는데, 이들 모델들은 정제되고 입증될 필요가 있고 모니터링 방법들도 개발되고 증명될 필요가 있다. 이 필요성들은 모니터링 되어지는 시범이나 연구 프로젝트를 통해 충족될 수 있다. 현재 $CO_2$ 저장을 시범해 보이는 상업적 프로젝트에는 Sleipner, Weyburn, ORC, In Salah가 있으며, 연구 프로젝트로는 West Pearl Queen, Nagaoka, Frio가 있다. 이 논문에서는 모니터링 되는 주입 프로젝트들 중 몇 개에 대해 서술한다. $CO_2$ 저장에 사용되는 저류층들과 관련된 모니터링 기술들을 간단히 살펴본다. 모델들을 증명하고 기술들을 개발하기 위해 이용되는 작은 규모의 연구프로젝트들이 기후 변화 완화에 이 기술들의 실행 가능성을 확립하는 큰 규모의 모니터링되는 주입들에 유용한지에 대해서는 논란거리이다.

• 한국미생물·생명공학회지
• /
• 제28권2호
• /
• pp.117-123
• /
• 2000

P. phosphoreum의 생존과 생체발광도는 온도에 의해 많은 영향을 받는다. 냉동 저장한 세포의 경우 glycerol의 보호 작용으로 세포농도와 생균수는 측정기간 동안 일정하게 유지된 반면 생체발광도는 glycerol 첨가 직후 급속히 감소하였으며, 저장 이후에도 감소된 생체발광도가 활성화되지 못하였다. 최적 생육온도인 $20^{\circ}C$의 경우 저장 초기 세포가 성장함에 따라 세포수의 증가를 보였으나 일정 시간 이후 세포 분해 현상으로 인하여 생균수 및 세포 집락수의 감소를 나타내었으며, 생체발광도는 저장 3일 이후 소멸되었다. 이와는 대조적으로 $4^{\circ}C$에 저장한 세포의 생체발광도는 저장 10일 동안 지속되어 가장 높은 생체발광 유지도를 나타내었으나 장기간 저온 저장으로 인하여 세포가 VBNC 상태에 돌입됨에 따라 총균수와 생균수는 일정한 반면 저장 10일 이후 세포 집락수의 급격한 감소를 나타내었으며, 저장 20일 이후 간균에서 구균으로 세포 형태상의 변화를 나타내었다. 이에 따라 세포 저장 시 접종원의 농도를 달리하여 VBNC 상태와 생체발광도의 관련성을 조사한 결과 VBNC 세포가 증가할수록 생체발광도의 감소를 나타내었다. 따라서 VBNC 세포를 감소시키기 위하여 세포를 고정화하여 저장한 결과 별도의 활성제 없이 실온에서 다시 활성화되어 고정화하지 않은 세포에 비해 2.3배 높은 생체발광유지도를 나타내었으며, 저온저장에 따른 platebility 소실과 세포 응축현상이 나타나지 않았다. 이러한 결과는 세포의 고정화 방법을 이용하여 $4^{\circ}C$에서도 세포의 생존 및 생체발광 유지도를 향상시킬 수 있으며, 동결 건조법의 단점을 보완해 줄 것으로 생각된다.

• Parasites, Hosts and Diseases
• /
• 제54권2호
• /
• pp.225-231
• /
• 2016

Human and animal alveolar echinococcosis (AE) are important helminth infections endemic in wide areas of the Northern hemisphere. Monitoring Echinococcus multilocularis viability and spread using real-time fluorescent imaging in vivo provides a fast method to evaluate the load of parasite. Here, we generated a kind of fluorescent protoscolices in vivo imaging model and utilized this model to assess the activity against E. multilocularis protoscolices of metformin (Met). Results indicated that JC-1 tagged E. multilocularis can be reliably and confidently used to monitor protoscolices in vitro and in vivo. The availability of this transient in vivo fluorescent imaging of E. multilocularis protoscolices constitutes an important step toward the long term bio-imaging research of the AE-infected mouse models. In addition, this will be of great interest for further research on infection strategies and development of drugs and vaccines against E. multilocularis and other cestodes.

• Journal of Microbiology and Biotechnology
• /
• 제21권2호
• /
• pp.204-211
• /
• 2011

To yield high concentrations of protein expressed by genetically modified Escherichia coli, it is important that the bacterial strains are cultivated to high cell density in industrial bioprocesses. Since the expressed target protein is mostly accumulated inside the E. coli cells, the cellular product formation can be directly correlated to the bacterial biomass concentration. The typical way to determine this concentration is to sample offline. Such manual sampling, however, wastes time and is not efficient for acquiring direct feedback to control a fedbatch fermentation. An E. coli K12-derived strain was cultivated to high cell density in a pressurized stirred bioreactor on a pilot scale, by detecting biomass concentration online using a capacitance probe. This E. coli strain was grown in pure minimal medium using two carbon sources (glucose and glycerol). By applying exponential feeding profiles corresponding to a constant specific growth rate, the E. coli culture grew under carbon-limited conditions to minimize overflow metabolites. A high linearity was found between capacitance and biomass concentration, whereby up to 85 g/L dry cell weight was measured. To validate the viability of the culture, the oxygen transfer rate (OTR) was determined online, yielding maximum values of 0.69 mol/l/h and 0.98mol/l/h by using glucose and glycerol as carbon sources, respectively. Consequently, online monitoring of biomass using a capacitance probe provides direct and fast information about the viable E. coli biomass generated under aerobic fermentation conditions at elevated headspace pressures.