• Environmental Analysis Health and Toxicology
• /
• 제20권4호통권51호
• /
• pp.297-302
• /
• 2005

The purpose of this study was to provide the standard method for the analysis of organophosphorous pesticides such as chlorpyrifos, diazinon, malathion and parathion in blood. We performed method validation for these pesticides in blood according to EURACHEM (A focus For Analytical Chemistry in Europe) guide. For the analysis of the pesticides, we used solid-phase extraction ,column (Waters Oasis $HLB^{(R)}$. After the extraction, the supernatants were evaporated to dryness under the nitrogen stream. They were analyzed by gas chromatography/mass spectrometry (GC/MS) after reconstituting with ethanol. Terbufos was used as an internal standard. To validate this method, we performed verification procedures with the following parameters: selectivity, linearity of calibration, accuracy, precision, limit of detection and quantification. Validation data according to Eurachem guide were adequate for our purpose for the analysis of chlorpyrifos, diazinon, malathion and parathion in blood.

• Korea-Australia Rheology Journal
• /
• 제17권2호
• /
• pp.47-62
• /
• 2005

The present study deals with a mathematical model describing the dynamic response of heat and mass transfer in blood flow through bifurcated arteries under stenotic condition. The geometry of the bifurcated arterial segment possessing constrictions in both the parent and the daughter arterial lumen frequently appearing in the diseased arteries causing malfunction of the cardiovascular system, is formulated mathematically with the introduction of the suitable curvatures at the lateral junction and the flow divider. The blood flowing through the artery is treated to be Newtonian. The nonlinear unsteady flow phenomena is governed by the Navier-Stokes equations while those of heat and mass transfer are controlled by the heat conduction and the convection-diffusion equations respectively. All these equations together with the appropriate boundary conditions describing the present biomechanical problem following the radial coordinate transformation are solved numerically by adopting finite difference technique. The respective profiles of the flow field, the temperature and the concentration and their distributions as well are obtained. The influences of the stenosis, the arterial wall motion and the unsteady behaviour of the system in terms of the heat and mass transfer on the blood stream in the entire arterial segment are high­lighted through several plots presented at the end of the paper in order to illustrate the applicability of the present model under study.

• Journal of Microbiology and Biotechnology
• /
• 제31권11호
• /
• pp.1481-1489
• /
• 2021

Early and accurate detection of pathogens is important to improve clinical outcomes of bloodstream infections (BSI), especially in the case of drug-resistant pathogens. In this study, we aimed to develop a culture-independent digital PCR (dPCR) system for multiplex detection of major sepsis-causing gram-negative pathogens and antimicrobial resistance genes using plasma DNA from BSI patients. Our duplex dPCR system successfully detected nine targets (five bacteria-specific targets and four antimicrobial resistance genes) through five reactions within 3 hours. The minimum detection limit was 50 ag of bacterial DNA, suggesting that 1 CFU/ml of bacteria in the blood can be detected. To validate the clinical applicability, cell-free DNA samples from febrile patients were tested with our system and confirmed high consistency with conventional blood culture. This system can support early identification of some drug-resistant gram-negative pathogens, which can help improving treatment outcomes of BSI.

• 한국콘텐츠학회논문지
• /
• 제14권11호
• /
• pp.838-848
• /
• 2014

본 연구의 목적은 2% 클로르헥시딘 침상목욕 간호가 중환자실 입원환자의 MRSA (Methicillin-resistant Staphylococcus aureus) 발생률과 BSI (blood stream infection) 발생률에 미치는 효과를 검증하고 치료적인 침상목욕 방법을 제시하기 위함이다. 본 연구의 대상자는 서울에 소재한 1개 상급 종합병원의 내 외과계중환자실에 2010년 11월 1일부터 2011년 8월 15일까지 입실한 환자 전수로 하였으며, 실험군 188명, 대조군 199명으로 총 387명이었다. 2% 클로르헥시딘(MICROSHIELD $2^{(R)}$, 존슨앤존슨, 뉴질랜드) 침상목욕 간호를 실시한 실험군의 MRSA 발생률은 7.4%로 일반 비누와 액상 세정제를 사용하여 침상목욕 간호를 실시한 대조군의 MRSA 발생률 14.1%보다 유의하게 낮았다(p=.036). 실험군의 재원일수 1,000일당 MRSA 발생건수는 9.32건으로 대조군의 재원일수 1,000일당 발생건수 15.44건보다 낮았다(p=.099). 2% 클로르헥시딘 침상목욕 간호를 실시한 실험군의 BSI 발생률은 0.5%로 일반 비누와 액상 세정제를 사용하여 침상목욕 간호를 실시한 대조군의 BSI 발생률 5.0%보다 유의하게 낮았다(p=.011). 실험군의 재원일수 1,000일당 BSI 발생건수가 0.67건으로 대조군의 재원일수 1,000일당 발생건수 5.52건에 비해 낮게 나타났다(p=.052). 따라서 2% 클로르헥시딘 침상목욕 간호를 치료적 간호중재로 간호실무에 적극적으로 활용할 것을 제안한다.

• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1997년도 춘계학술대회
• /
• pp.188-191
• /
• 1997

In this paper, we present a real-time remote patient monitoring service through world-wide web, which allows the medical doctor to monitor his patients in remote sites using popular web browsers. The real-time service consists of two services: Patient Locator Service (PLS) and Vital Sign Monitoring Service (VSMS). The PLS provides the information of patients currently being monitored. The VSMS allows the user to observe a stream of vital sign data of a specific patient. The vital sign data include ECG, respiration, temperature, $SPO_2$, invasive blood pressure and non-invasive blood pressure.

• International Journal of Vascular Biomedical Engineering
• /
• 제3권2호
• /
• pp.1-9
• /
• 2005

Flow-induced dilation of blood vessel is the result of a series of bioreaction in vascular endothelial cells(VEC). Shear stress change by blood flow in human artery or vein is sensed by the mechanoreceptor and responsible for such a chain reaction. The inositol(1,4,5)-triphophate($IP_3$) is produced in the first stage to elevate permeability of the intercellular membrane to calcium ions by which the cytosolic calcium concentration is consequently increased. This intracellular calcium transient triggers synthesis of EDRF and prostacyclin. The mathematical model of this VEC calcium dynamics is reproduced from the literature. We then use the Computational Fluid Dynamics(CFD) technique to investigate the blood stream dictating the VEC calcium dynamics. The pulsatile blood flow in a stenosed blood vessel is considered here as a part of study on thrombogenesis. We calculate the pulsating shear stress (thus its temporal change) distributed over the stenosed artery that is implemented to the VEC calcium dynamics model. It has been found that the pulsatile shear stress induces larger intracellular $Ca^{2+}$ transient plus much higher amount of EDRF and prostacyclin release in comparison with the steady shear stress case. It is concluded that pulsatility of the physiological shear stress is important to keep the vasodilation function in the stenosed part of the blood vessel.

• 한국환경과학회지
• /
• 제22권12호
• /
• pp.1615-1624
• /
• 2013

The aims of this study were to investigate and confirm the occurrence and distribution patterns of blood lipid lower agents (BLLAs) in Nakdong river basin (mainstream and its tributaries). 4 (atorvastatin, lovastatin, mevastatin and simvastatin) out of 5 statins and 2 (clofibric acid and zemfibrozil) out of 3 fibrates were detected in 29 sampling sites and simvastatin (>50%) was predominant compound followed by atorvastatin, lovastatin and clofibric acid. The total concentration levels of BLLAs on April, August and November 2009 in surface water samples ranged from ND~25.7 ng/L, ND~18.8 and ND to 38.8 ng/L, respectively. The highest concentration level of BLLAs in the mainstream and tributaries in Nakdong river were Goryeong and Jincheon-cheon, respectively. The sewage treatment plants (STPs) along the river affect the BLLAs levels in river and the BLLAs levels decreased with downstream because of dilution effects.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권3호
• /
• pp.1609-1614
• /
• 2013

Objective: To evaluate the effect of intravenous contrast on dose calculation in radiation treatment planning for oesophageal cancer. Methods: A total of 22 intravein-contrasted patients with oesophageal cancer were included. The Hounsfield unit (HU) value of the enhanced blood stream in thoracic great vessels and heart was overridden with 45 HU to simulate the non-contrast CT image, and 145 HU, 245 HU, 345 HU, and 445 HU to model the different contrast-enhanced scenarios. 1000 HU and -1000 HU were used to evaluate two non-physiologic extreme scenarios. Variation in dose distribution of the different scenarios was calculated to quantify the effect of contrast enhancement. Results: In the contrast-enhanced scenarios, the mean variation in dose for planning target volume (PTV) was less than 1.0%, and those for the total lung and spinal cord were less than 0.5%. When the HU value of the blood stream exceeded 245 the average variation exceeded 1.0% for the heart V40. In the non-physiologic extreme scenarios, the dose variation of PTV was less than 1.0%, while the dose calculations of the organs at risk were greater than 2.0%. Conclusions: The use of contrast agent does not significantly influence dose calculation of PTV, lung and spinal cord. However, it does have influence on dose accuracy for heart.

• 공업화학
• /
• 제29권2호
• /
• pp.147-154
• /
• 2018

현재 항암제의 낮은 치료 효율과 부작용을 해결하기 위해 고분자 기반의 약물전달체의 연구가 활발하게 진행되고 있다. 기존의 고분자기반의 약물 전달체는 우수한 결과를 보이는 등 상당한 진전이 있었음에도 불구하고, 대부분 혈중에서 안정성이 감소하여 표적 부위에 도달하기 전에 약물이 방출될 뿐만 아니라 오랜 시간 동안에 약물을 방출함으로써 부작용 및 낮은 치료 효율을 초래한다는 문제점을 가지고 있다. 본 총론에서는 이러한 비효율적인 약물 방출의 문제점을 개선하기 위한 방법으로 독성이 없고 생체 적합한 천연 고분자 키토산에 자극 응답성 물질을 도입하여 혈중에서 안정성을 높이고 표적 부위에서 약물을 과다 방출하여 치료 효율을 극대화할 수 있는 방법을 제시하고자 한다.

• Animal cells and systems
• /
• 제16권4호
• /
• pp.329-336
• /
• 2012

This study evaluated ecological health, using various biomarkers and bioindicators, of pale chub (Zacco platypus) as a sentinel species, in Daejeon Stream, South Korea, during AprilMay 2011. The biomarkers and bioindicators were compared among three sites of control: Reference ($C_z$), transition ($T_z$), and the urban zones ($U_z$); and the 7-Ethoxyresorufin-O-deethylase (EROD) activity, DNA damage, acetylcholinesterase (AChE) activity, and vitellogenin (VTG) concentrations were more significantly increased in the $U_z$ than in the $C_z$. Also, physiological markers such as condition factor, liver somatic index, visceral somatic index, and gonad somatic index were significantly increased in the $U_z$ than in the $C_z$. For the health assessments, three categorized parameters of blood chemistry, molecular biomarkers, and physiological bioindicators were standardized and calculated as a star-plot, representing values of Integrated Health Response (IHR). Values of IHR had more significant (P<0.05) increases in the $U_z$ than any other zones, indicating an impairment of ecological health by organic matter, nutrients (N, P), and toxic chemicals. This study is based on low levels of biological organization approach of molecular and physiological biomarkers and bioindicators, so further study of high-levels of biological organization approach such as community and population is required for overall range of health assessments. The approach of IHR values, however, may be useful in providing early warning of future impacts on ecological health.