• 제목/요약/키워드: the volume functional

검색결과 754건 처리시간 0.03초

Right ventricular failure in congenital heart disease

  • Cho, Young Kuk;Ma, Jae Sook
    • Clinical and Experimental Pediatrics
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    • 제56권3호
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    • pp.101-106
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    • 2013
  • Despite developments in surgical techniques and other interventions, right ventricular (RV) failure remains an important clinical problem in several congenital heart diseases (CHD). RV function is one of the most important predictors of mortality and morbidity in patients with CHD. RV failure is a progressive disorder that begins with myocardial injury or stress, neurohormonal activation, cytokine activation, altered gene expression, and ventricular remodeling. Pressure-overload RV failure caused by RV outflow tract obstruction after total correction of tetralogy of Fallot, pulmonary stenosis, atrial switch operation for transposition of the great arteries, congenitally corrected transposition of the great arteries, and systemic RV failure after the Fontan operation. Volume-overload RV failure may be caused by atrial septal defect, pulmonary regurgitation, or tricuspid regurgitation. Although the measurement of RV function is difficult because of many reasons, the right ventricle can be evaluated using both imaging and functional modalities. In clinical practice, echocardiography is the primary mode for the evaluation of RV structure and function. Cardiac magnetic resonance imaging is increasingly used for evaluating RV structure and function. A comprehensive evaluation of RV function may lead to early and optimal management of RV failure in patients with CHD.

Overexpression, Purification, and Preliminary X-Ray Crystallographic Studies of Methionine Sulfoxide Reductase B from Bacillus subtilis

  • Park, Ae-Kyung;Shin, Youn-Jae;Moon, Jin-Ho;Kim, Young-Kwan;Hwang, Kwang-Yeon;Chi, Young-Min
    • Journal of Microbiology and Biotechnology
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    • 제18권1호
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    • pp.59-62
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    • 2008
  • The peptide methionine sulfoxide reductases (Msrs) are enzymes that catalyze the reduction of methionine sulfoxide back to methionine. Because of two enantiomers of methionine sulfoxide (S and R forms), this reduction reaction is carried out by two structurally unrelated classes of enzymes, MsrA (E.C. 1.8.4.11) and MsrB (E.C. 1.8.4.12). Whereas MsrA has been well characterized structurally and functionally, little information on MsrB is available. The recombinant MsrB from Bacillus subtilis has been purified and crystallized by the hanging-drop vapor-diffusion method, and the functional and structural features of MsrB have been elucidated. The crystals belong to the trigonal space group P3, with unit-cell parameters a=b=136.096, $c=61.918{\AA}$, and diffracted to $2.5{\AA}$ resolution using a synchrotron-radiation source at Pohang Light Source. The asymmetric unit contains six subunits of MsrB with a crystal volume per protein mass $(V_M)\;of\;3.37{\AA}^3\;Da^{-1}$ and a solvent content of 63.5%.

Removal of ciprofloxacin from aqueous solution by activated carbon prepared from orange peel using zinc chloride

  • Koklu, Rabia;Imamoglu, Mustafa
    • Membrane and Water Treatment
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    • 제13권3호
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    • pp.129-137
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    • 2022
  • In this study, the removal of Ciprofloxacin (CPX) from aqueous solutions was investigated by a new activated carbon adsorbent prepared from orange peel (ACOP) with chemical activation using ZnCl2. The physicochemical properties of orange peel activated carbon were characterized by proximate and ultimate analysis, scanning electron microscopy, BET surface area determination and Fourier transformation infrared spectroscopic studies. According to Brunauer-Emmett-Teller isotherm and non-local-density functional theory, the cumulative surface area, pore volume and pore size of ACOP were determined as 1193 m2 g-1, 0.83 cc g-1 and 12.7 Å, respectively. The effects of contact time, pH, temperature and ACOP dose on the batch adsorption of CPX were studied. Adsorption equilibrium data of CPX with ACOP were found to be compatible with both the Langmuir and Freundlich isotherms. CPX adsorption capacity of ACOP was calculated as 181.8 mg g-1 using Langmuir isotherm. The CPX adsorption kinetics were found to be harmonious with the pseudo-second-order kinetic model. Conclusively, ACOP can be assessable as an effective adsorbent for the removal of ciprofloxacin (CPX) from aqueous solutions.

What Is Normal for an Aging Heart?: A Prospective CMR Cohort Study

  • Johannes Kersten;Carsten Hackenbroch;Muriel Bouly;Benoit Tyl;Peter Bernhardt
    • Journal of Cardiovascular Imaging
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    • 제30권3호
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    • pp.202-211
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    • 2022
  • BACKGROUND: This study aims to investigate normal changes throughout aging of the heart in cardiac magnetic resonance (CMR) imaging in healthy volunteers. While type 2 diabetes mellitus is a frequent finding in the elderly population, also the influence of this circumstance in otherwise healthy persons is part of our study. METHODS: In this prospective single-center trial, 75 healthy subjects in distinct age groups and 10 otherwise healthy diabetics were enrolled. All subjects underwent functional, flow sensitive, native T2- and T1-mapping in a 1.5T CMR scanner. RESULTS: No differences in right and left ventricular ejection fractions were observed between aging healthy groups. Bi-ventricular volumes lowered significantly (p<0.001) between the age groups. There was also a significant decrease in myocardial T1 values, aortic distensibility, and left ventricular peak diastolic strain rates. There were no differences in T2 mapping and the other deformation parameters. Patients with type 2 diabetes mellitus had lower end-diastolic volume indexes; all the other measurements were comparable. CONCLUSIONS: Aging processes in the healthy heart involve a decrease in ventricular volumes, with ejection fractions remaining normal. Stiffening of the myocardium and aorta and a decrease in T1 values are potential indications of age-related remodeling. Type 2 diabetes mellitus seems to have no major influence on aging processes of the heart.

반응표면분석법을 사용한 가속 용매 추출에 의한 홍삼 지표성분의 추출 최적화 (Optimization of Extraction of Marker Compounds from Red Ginsengs by Accelerated Solvent Extraction Using Response Surface Methodology)

  • 김은옥;서구량;엄병헌
    • 한국식품영양과학회지
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    • 제45권8호
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    • pp.1162-1169
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    • 2016
  • 본 연구에서는 기능성 홍삼 엑기스 제조를 위해 추출용매, 압력, 온도, 추출시간을 조절하여 가속 용매 추출한 후 기능성 홍삼제품의 지표성분인 진세노사이드 함량, 총페놀화합물 및 벤조피렌 함량 등을 조사하였다. 홍삼 가속 용매 추출 최적화를 위한 독립변수 선택을 위해 에탄올 농도, 압력, 온도 및 추출시간에 따른 기능성 홍삼제품의 지표성분인 진세노사이드 Rb1, Rg1 및 Rg3(20S) 함량의 합을 분석하여 진세노사이드 추출에 가장 최적의 용매를 50% 에탄올로 하고, 영향이 다소 작았던 요인인 압력을 2,500 psi로 설정하였으며, 온도와 추출시간을 독립변수로 설정하였다. 추출 온도 및 시간을 독립변수로 하여 고온고압 처리한 홍삼의 진세노사이드 Rb1, Rg1 및 Rg3(20S) 함량의 합, 총 페놀성 화합물 및 벤조피렌 함량을 측정한 결과, 벤조피렌이 검출되지 않는 조건에서 진세노사이드 Rb1, Rg1 및 Rg3(20S)의 함량 합이 최적화된 조건은 $158^{\circ}C$, 20분임을 확인할 수 있었다. 최적화된 조건에서의 가속 용매 추출 시 초음파 및 환류냉각 추출에 비해 적은 용매로 단시간 추출하면서 진세노사이드 Rb1, Rg1 및 Rg3(20S) 함량 합 및 총폴리페놀 함량이 각각 1.5~2배 및 2.2~5배 높게 추출할 수 있어 효율적인 추출방법이 될 것으로 생각된다.

심장기능 평가를 위한 견 적출심장 관류장치의 설계 (Isolated Working Canine Heart Perfusion Apparatus for Evaluation of Myocardial Protection Methods)

  • 이종국
    • Journal of Chest Surgery
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    • 제21권2호
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    • pp.246-253
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    • 1988
  • An in vitro model providing with a recirculating perfusion apparatus using an isolated canine heart and its autogenous blood, which was prepared for study of myocardial protection method. This apparatus was easily used by quick connect system and maintained well heart function for about 2 hours. The Langendorff perfusion was initiated for a 10 minute period by introducing perfusate at 37` into the aorta from aortic reservoir located 100 cm above the heart. The isolated perfused working canine heart model was a left heart preparation in which oxygenated perfusion medium [at 37K] entered the cannulated left atrium at a constant flow rate [900ml/ min] under 20 mmHg overflow system and was spontaneously ejected[no electrical pacing] via an cannula against a hydrostatic pressure of 80 cm H2O. During this working period, various indices of cardiac function were measured. The cardiac functions were stable for over 2 hours with perfusion of Krebs-Henseleit solution and autologous blood[1:1] mixture in volume and maintained heart rate ]]3-122/bpm peak systolic pressure 109-113 mmHg, cardiac output 900 ml / min and left atrial mean pressure 8-9 mmHg. In this model, the efficiency of myocardia] protection could be easily measured by means of functional, enzymatic, biochemical and ultrastructural assessment. And also, we believe this model to be a useful assessment screening model of recovery state after long duration of myocardial preservation of donor heart without difficult transplantation procedures.

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자동차용 천연가스 저장을 위한 탄소매질 (Carbonaceous Media for Vehicular Natural Gas Storage)

  • 문희
    • 공업화학
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    • 제18권1호
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    • pp.1-9
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    • 2007
  • 천연가스는 가솔린에 비하여 에너지 밀도가 매우 낮아 천연가스 차량의 경우 약 24.8 MPa로 압축된 압축천연가스(CNG)를 이용하기 때문에 고압을 얻기 위하여 다단계 압축이 요구될 뿐 아니라 안정성에 문제가 많다. 이런 이유로 비교적 낮은 압력에서 저장할 수 있는 흡착천연가스에 관심을 갖게 되었다. 천연가스의 저장에 용이한 매질을 개발하여 3.5 MPa에서 CNG와 에너지 밀도가 유사하고, 같은 용적의 가솔린에 비하여 1/4 수준의 운전거리를 확보하는 것이 현재의 목표이다. 본 총설에서는 흡착천연가스(ANG) 저장을 위한 탄소매질의 개발현황, 매질의 특성 및 실용화를 위하여 진행되고 있는 내용을 간략하게 소개하고 몇 가지 필요한 제언을 한다.

강황분말을 첨가한 만두피의 품질특성 (Quality Characteristics of Mandupi Added with Curcuma aromatica Powder)

  • 박복희;안성아;조희숙
    • 한국식생활문화학회지
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    • 제29권4호
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    • pp.348-354
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    • 2014
  • The purpose of this study was to investigate the effects of Curcuma aromatica powder on the functional and sensory characteristics of Mandupi. Various Mandupi samples were prepared with wheat flour along with addition of various amounts of Curcuma aromatica powder, after which instrumental characteristics and sensory evaluations were investigated. According to the amylograph data, the composite Curcuma aromatica powder-wheat flour samples showed increased gelatinization temperatures with increasing Curcuma aromatica powder content, whereas initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity were reduced. In terms of Hunter's color values, L value decreased while a and b values increased with increasing Curcuma aromatica powder content. Besides cooked weight, cooked volume and turbidity of Mandupi increased as the addition level of Curcuma aromatica powder increased. In terms of textural characteristics, addition of Curcuma aromatica powder increased springiness, chewiness, and brittleness, whereas springiness and adhesiveness decreased. Based on sensory evaluations, the overall preference of Mandupi with 3% added Curcuma aromatica powder was higher than that of control.

건식코팅장치를 이용하여 제조한 NH2-HNT를 충진재로 응용한 에폭시 복합체의 기계적 물성 향상 (Improvement of Mechanical Properties of Epoxy Composites Using NH2-HNT Manufactured by Dry Coating Device as Filler)

  • 김문일
    • 한국산업융합학회 논문집
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    • 제27권2_2호
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    • pp.371-375
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    • 2024
  • Epoxy resins are widely used in various fields due to their high adhesion, mechanical strength, and solvent resistance. However, as the volume decreases during the hardening process and the cooling process after hardening, stress is generated and when an external force is applied, the brittle material exhibits destruction behavior. To complement this, research has been conducted using inorganic nanofillers such as halloysite nanotube(HNT). HNT has a nanotube structure with the chemical formula of Al2Si2O5(OH)4·nH2O and is a natural sediment of aluminosilicate. It has been used as additive to improve the mechanical properties of epoxy composites with exchange of amine group as a terminal functional group. In order to simplify complicated procedures of common wet method, a dry coating machine was designed and used for amine group exchange in previous research. In this study, they were applied as filler in epoxy composites, and mechanical properties such as tensile strength and flexural strength of composites were examined.

관절염 유발 동물 모델에서 이소에고마케톤 함유 패치의 관절염 치료 효과 (The Therapeutic Effect of Medical Patches Including Isoegomaketone on the Collagen Antibody-induced Arthritis in Mice)

  • 진창현;김예람;한아름
    • 방사선산업학회지
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    • 제17권4호
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    • pp.327-332
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    • 2023
  • This study identified effects of Isoegomaketone for applicable patch on the arthritis in mice. Isoegomaketone (IK) was isolated from Perilla frutescens, which is annual herbal traditional medicinal, aromatic, functional food. IK has various physiological effects such as anti-inflammation, anti-oxidant, and anti-cancer. In the previous study, oral administration of IK to a mouse model of collagen antibody-induced arthritis(CAIA), which is similar to human rheumatoid arthritis(RA), alleviated symptoms. In this study, we attached a patch containing IK to mouse skin to demonstrate whether it had the same efficacy as oral administration in CAIA mouse. As a result of measuring the arthritis score, paw volume, and paw thickness, it was confirmed that arthritis symptoms were alleviated in the group to which the patch containing IK was attached. These results show that IK is effective in alleviating arthritis not only through oral administration but also through patches applied to skin, and that it has potential as a material for future patch development.