• 제목/요약/키워드: disease gradient

검색결과 129건 처리시간 0.029초

Williams syndrome의 외과적 치험 (Surgical Treatment of the Williams Syndrome)

  • 홍민수
    • Journal of Chest Surgery
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    • 제25권9호
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    • pp.925-929
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    • 1992
  • Supravalvular aortic stenosis is relatively uncommon form of congenital heart disease and the most important lesion of this anomaly is various narrowing of the aortic lumen just above the sinus of Valsalva. We experienced a case of hourglass type of supravalvular aortic stenosis involving lcm from length from lcm above the sinus of Valsalva. The patient was associated with mental retardation, peculiar facies and dental anomaly. The diagnosis was confirmed preoperatively by retrograde left heart catheterization and left ventriculography. An incision was made in the ascending aorta and into the right coronary and noncornary sinus. Care was taken to protect the right coronary artery. A Y-shaped patch of Dacron was made to enlarge the stenotic portion of aorta. Postoperative pressure gradient between the aorta and left ventricle markedly reduced 36 mmHg in comparison with preoperative pressure gradient 150mmHg. The boy was discharged without any event.

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동맥경화증의 발생에 관한 혈류역학적 가설들에 대한 비교연구 (A Comparative Study of the Hemodynamic Hypotheses for the Generation of Atherosclerosis)

  • 서상호;조민태;노형운;권혁문
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1915-1918
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    • 2003
  • Atherosclerosis, which is a degenerate disease, is believed to occur in the vascular system due to deposition of cholesterol and low density lipoprotein(LDL) or thrombosis on the blood vessel. Atherosclerosis narrows arterial lumen, which is known as stenosis phenomenon of blood vessel. Pathogenesis of atherosclerosis is thought to occur mainly by aging. Restenosis phenomenon is observed in the same site of insertion of a stent and balloon angioplasty after treatment of interventional theraphy. Several hypothetical theories related to the generation of atherosclerosis have been reported: high shear stress theory, low shear stress theory, high shear stress gradient theory, flow separation and turbulence theory and high pressure theory. However, no one theory clearly explains the causes of atherosclerosis. In the present study the generation of atherosclerosis in the left coronary artery is investigated. The hypotheses are verified by using the computer simulation.

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조절성 폭주비(AC/A) 측정에 의한 양안시 기능 분석 (The Analysis of Binocular Vision Function by measuring Accommodative Convergence(AC/A))

  • 강인산;서용원;최지영
    • 한국안광학회지
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    • 제10권3호
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    • pp.159-164
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    • 2005
  • 조절과 폭주기능은 밀접하게 연관된 합동운동으로 폭주와 조절 어느 한 쪽이 자극되면 양기능이 동시에 일어난다. 이 중 조절자극에 의해 일어나는 폭주를 조절성 폭주라고 하며, 눈의 굴절상태에 따라 과부족이 있다. 본 연구는 조절성 폭주비와 사위와의 관계를 규명하기 위해 그래디앤트(Gradient)법과 헤트로포리아(Heterophoria)법 둘 다 모두 사용하여 안과적 질환이 없는 성인 남녀 41명을 대상으로 검사하였다. 1. 원거리 사위분포를 조사한 결과, 정위 5명, 외사위 32명, 내사위 4명으로 외사위가 가장 많은 비율을 차지하고 있었다. 근거리 사위분포도는 원거리보다 넓게 퍼져서 분포하고 있었다. 2. 수정체의 조절력을 이완시킨 상태에서 수평사위량 측정시, 38명이 외사위량이 증가하였다. 3. 정상 AC/A ratio에 해당하는 $4{\sim}6{\Delta}/D$를 갖는 사람이 Heterophoria법에서는 27명으로 약 66%를, Gradient 법에서는 16명으로 39%를 각각 차지하고 있었다.

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SWI의 신경영상분야의 임상적 이용 (Clinical Applications of Neuroimaging with Susceptibility Weighted Imaging: Review Article)

  • 노근탁;강현구;김인중
    • Investigative Magnetic Resonance Imaging
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    • 제18권4호
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    • pp.290-302
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    • 2014
  • 목적: 자화율 강조 자기공명영상 (Susceptibility-weighted imaging)은 혈액분해산물, 석회화, 철 침착물을 발견하는데 있어 높은 민감도를 보이는 3D spoiled gradient-echo pulse sequence 이다. 본 임상화보는 자화율 강조 자기공명영상의 주된 임상적 적용에 대해 설명하고 논의하는 데에 그 목적이 있다. 대상과 방법: 자화율 강조 자기공명영상은 자기강도영상 (magnitude image)과 위상영상 (phase image)을 이용한 고해상도, 3D fully velocity-compensated gradient-echo sequence 에 기초를 두고 있다. 정맥 구조물의 가시성을 향상시키기 위해, 자기강도영상은 여과된 위상 데이터 (phase data) 로부터 발생된 위상 마스크 (phase mask)를 이용해 증폭되고, 이것은 최소강도투사 (Minimal intensive projection) 알고리즘을 이용한 3D dataset 후처리 과정을 거치게 된다. 3T 자기공명기기에서 SWI를 포함하는 자기공명영상 검사를 시행한 총 200명의 환자를 대상으로 연구하였다. 결과: 자화율 강조 자기공명영상은 다양한 뇌 질환의 발견에 매우 유용하였다. 200명의 환자 중 80명은 선천성 정맥 기형, 22명은 해면상 혈관종, 12명은 다양한 질환에서의 석회화, 21명은 혈관자화 징후 (susceptibility vessel sign) 또는 미세출혈을 동반하는 뇌혈관 질환, 52명은 뇌종양, 2명은 미만성 축삭 손상, 3명은 동정맥 기형, 5명은 뇌경막 동정맥루, 1명은 모야모야병, 그리고 2명은 파킨슨병이 관찰되었다. 결론: 자화율 강조 자기공명영상은 미세 저혈량 혈관성 병변, 석회화 그리고 미세출혈과 다양한 뇌병변의 진단에 유용하다.

Optical Sensing for Evaluating the Severity of Disease Caused by Cladosporium sp. in Barley under Warmer Conditions

  • Oh, Dohyeok;Ryu, Jae-Hyun;Oh, Sehee;Jeong, Hoejeong;Park, Jisung;Jeong, Rae-Dong;Kim, Wonsik;Cho, Jaeil
    • The Plant Pathology Journal
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    • 제34권3호
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    • pp.236-240
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    • 2018
  • Crop yield is critically related to the physiological responses and disease resistance of the crop, which could be strongly affected by high temperature conditions. We observed the changes in the growth of barley under higher than ambient air-temperature conditions using a temperature gradient field chamber (TGFC) during winter and spring. Before the stem extension stage of barley growth, Cladosporium sp. spontaneously appeared in the TGFC. The severity of disease became serious under warmer temperature conditions. Further, the stomata closed as the severity of the disease increased; however, stomatal conductance at the initial stage of disease was higher than that of the normal leaves. This was likely due to the Iwanov effect, which explains that stressed plants rapidly and transiently open their stomata before longer-term closure. In this study, we tested three optical methods: soil-plant analysis development (SPAD) chlorophyll index, photochemical reflectance index (PRI), and maximum quantum yield (Fv/Fm). These rapid evaluation methods have not been used in studies focusing on disease stress, although some studies have used these methods to monitor other stresses. These three indicative parameters revealed that diseased barley exhibited lower values of these parameters than normal, and with the increase in disease severity, these values declined further. Our results will be useful in efficient monitoring and evaluation of crop diseases under future warming conditions.

윤상 교약성 심낭염의 외과적 치료 -2예 보고- (Annular Constrictive Pericarditis: Simulating Vavular Heart Disease : Case Report)

  • 유회성
    • Journal of Chest Surgery
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    • 제13권3호
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    • pp.280-284
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    • 1980
  • This is report of two cases of annular constrictive pericarditis. Since January 1959 to December 1979 the authors experienced 48 cases of chronic constrictive pericarditis treated surgically at the Department of Thoracic and Cardiovascular Surgery, the National Medical Center in Seoul. These cases simulated valvular heart disease. One case, as mitral stenosis, revealed rumbling apical diastolic murmur [II/VI], atrial fibrillation and right ventricular hypertrophy pattern on E.C.G., the other, as infundibular pulmonic stenosis, presented pressure gradient between right ventricle and main pulmonary artery at infundibular level of 76 mmHg in systole. Both patients underwent operation successfully and one of them was assisted by E.C.C. during pericardiectomy and result was excellent. It is difficult to make the diagnosis of these conditions preoperatively so consideration about these might be important to make the diagnosis accurately.

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특발성 비후성 대동맥판하 협착증 및 승모판 폐쇄부전증 -3례 보고- (Idiopathic Hypertropic Subaortic Stenosis with Mitral Regurgitation -Report of 3 Cases-)

  • 강청희
    • Journal of Chest Surgery
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    • 제27권4호
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    • pp.313-317
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    • 1994
  • Surgical treatment is possible for the obstructive form of hypertrophic cardiomyopathy and transaortic left ventricular septal myectomy and myotomy has been the procedure of choice. If coexisting intrinsic mitral valve disease exists, mitral valve replacement has been performed. But abnormal systolic anterior motion of anterior mitral leaflet[SAM] with intrinsic normal mitral valve disease is the typical feature of IHSS and we prefer not to replace mitral valve. 3 patients underwent transaortic myotomy and myectomy for IHSS with mitral regurgitation. 2 patients of them have coexisting intrinsic mitral valve diseases such as mitral valve vegetation and chorda rupture. Concomittent mitral valve replacement were performed. 1 patient shows SAM of mitral anterior leaflet but has intrinsic normal mitral valve morphologically and transepicardial echocardiogram and direct monitoring of pressure gradient during the operative procedure gives better information for subsided mitral regurgitation. Post operative course during the 12 months follow-up was uneventful.

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Evaluation of plasma N-terminal pro-brain natriuretic peptide and troponin I concentrations in dogs with congenital ventricular outflow tract stenosis

  • Kim, Gye-Dong;Suh, Sang-IL;Park, In-Chul;Hyun, Changbaig
    • 대한수의학회지
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    • 제56권4호
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    • pp.223-227
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    • 2016
  • This study evaluated the levels of cardiac biomarkers in dogs with either pulmonic stenosis or aortic stenosis and the correlation between biomarkers and the severity of stenosis assessed by the echocardiography. To achieve this study goal, 38 dogs (10 healthy control dogs, 15 dogs with pulmonic stenosis and 13 dogs with aortic stenosis) were examined. The jet velocity and pressure gradient in this study population were measured by echocardiographic estimation, after which the study group was subdivided by the severity of stenosis. The plasma cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured in this study group. The median concentrations of cTnI and NT-proBNP of the disease group were significantly higher than those of the control group, and these increased gradually as stenosis worsened. The severity of stenosis and the concentrations of cTnI and NT-porBNP were also found to be significantly correlated. Finally, the plasma cTnI and NT-proBNP tests were found to beneficial for differentiating clinical patients, predicting the progression of disease, and monitoring the outcome of interventional therapy for stenosis.

β-Secretase (BACE1) Purification by Refolding Method and Complex with Hispidin

  • Lim, Ji-Hong;Lee, Bo Ram;Park, Hee Won;Hong, Bum Soo;Lim, Beong Ou;Kim, Young Jun
    • 대한화학회지
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    • 제58권6호
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    • pp.553-559
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    • 2014
  • Alzheimer's disease (AD) is a devastating neurodegenerative disease that represents the most common form of dementia among the elderly population. The deposition of aggregated ${\beta}$-amyloid ($A{\beta}$) senile plaques in the human brain is a classic observation in the neuropathology of AD, yet an understanding of the mechanism of their formation remains elusive. $A{\beta}$ is formed through endoproteolysis of the amyloid precursor protein (APP) by ${\beta}$-secretase (BACE1, ${\beta}$-site APP-cleaving enzyme) and ${\gamma}$-secretase. In this study, BACE1 protein was successfully over-expressed, purified, and refolded and utilized in a binding study with hispidin. We developed a simpler refolding method using a urea gradient and size-exclusion gel filtration to purify an active BACE1 protein variant, in larger quantities than that reported previously, and measured the binding affinity of hispidin to the BACE1 protein variant through isothermal titration calorimetry.

A Fluorescent Recombinase Aided Amplification Assay for Detection of Babesia microti

  • Lin, Hong;Zhao, Song;Ye, Yuying;Shao, Lei;Jiang, Nizhen;Yang, Kun
    • Parasites, Hosts and Diseases
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    • 제60권3호
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    • pp.201-205
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    • 2022
  • Babesia microti is one of the most common causative agents of babesiosis. A sensitive and rapid detection is necessary for screening potentially infected individuals. In this study, B. microti cytochrome c oxidase subunit I (cox1) was selected as the target gene, multiple primers were designed, and optimized by a recombinase-aided amplification (RAA) assay. The optimal primers and probe were labeled with fluorescein. The sensitivity of fluorescent RAA (fRAA) was evaluated using gradient diluents of the cox1 recombinant plasmid and genomic DNA extracted from whole blood of B. microti infected mice. The specificity of fRAA was assessed by other transfusion transmitted parasites. The analytical sensitivity of the fRAA assay was 10 copies of recombinant plasmid per reaction and 10 fg/µl B. microti genomic DNA. No cross-reaction with any other blood-transmitted parasites was observed. Our results demonstrated that the fRAA assay would be rapid, sensitive, and specific for the detection of B. microti.