• 제목/요약/키워드: HEART

검색결과 11,094건 처리시간 0.035초

Engineered human cardiac tissues for modeling heart diseases

  • Sungjin Min;Seung-Woo Cho
    • BMB Reports
    • /
    • 제56권1호
    • /
    • pp.32-42
    • /
    • 2023
  • Heart disease is one of the major life-threatening diseases with high mortality and incidence worldwide. Several model systems, such as primary cells and animals, have been used to understand heart diseases and establish appropriate treatments. However, they have limitations in accuracy and reproducibility in recapitulating disease pathophysiology and evaluating drug responses. In recent years, three-dimensional (3D) cardiac tissue models produced using tissue engineering technology and human cells have outperformed conventional models. In particular, the integration of cell reprogramming techniques with bioengineering platforms (e.g., microfluidics, scaffolds, bioprinting, and biophysical stimuli) has facilitated the development of heart-on-a-chip, cardiac spheroid/organoid, and engineered heart tissue (EHT) to recapitulate the structural and functional features of the native human heart. These cardiac models have improved heart disease modeling and toxicological evaluation. In this review, we summarize the cell types for the fabrication of cardiac tissue models, introduce diverse 3D human cardiac tissue models, and discuss the strategies to enhance their complexity and maturity. Finally, recent studies in the modeling of various heart diseases are reviewed.

머리 착용형 6축 가속도계를 사용한 심탄도 심박수 측정 (Ballistocardiographical Heart Rate Measurement Using Head Mounted 6-axis Accelerometer)

  • 김진만;국중진
    • 반도체디스플레이기술학회지
    • /
    • 제23권2호
    • /
    • pp.33-37
    • /
    • 2024
  • Recently, wearable virtual reality devices are widely used. These instruments include a 3-axis accelerometer. User's heart rate information in virtual reality contents can be useful for measuring user experience. In this paper, we propose a method to measure the heart rate through a 3-axis accelerometer based on the principle of ballistocardiography without additional sensors. The angular velocity was successively measured in a time series by the 3-axis accelerometer mounted to the head. The frequency of the maximum magnitude is determined as the heart rate through frequency transform and band pass filtering of the time series signal. For verification, the heart rate calculated from photoplethysmography sensors acquired at the same time was compared as ground-truth. In the virtual reality, the user's heart rate information can be extracted without additional heart rate sensor, and the emotional state and fatigue can be measured.

  • PDF

등산운동의 생리학적 분석 (Physiological analysis of mountain climbing exercise)

  • 김완태;남기용
    • The Korean Journal of Physiology
    • /
    • 제5권2호
    • /
    • pp.15-27
    • /
    • 1971
  • Physiological analysis of the physical exercise was made on 9 subjects performing mountain climbing. The course between two points (256 and 516 meters altitude) was 1,300 meters in distance and difference of vertical height was 260 meters making the mean grade of 20%. In the field, the heart rates during uphill or downhill walk were recorded by EKG radio-telemetry. In the laboratory, oxygen consumption was obtained by the recorded heart rates, using individual heart rate vs oxygen consumption diagram obtained by treadmill test. the following results were obtained. 1. Uphill walk time was 36.5 minutes, and during this period the mean heart rate was 149.0 heats/min and peak heart rate was 169.2 beats/min. The total heart beats during the uphill walk was 5.433 beats. 2. The ratio of individual mean heart rate during the uphill walk to the maximal heart rate distributed between 66.6% and 98.3%, and the mean of the total group was 83.1%. The ratio of peak heart rate of uphill walk to the maximal heart rate was 94.5% in the group. Thus uphill walk of a 20% grade mountain course was an exhaustive exercise. 3. Oxygen consumption during uphill walk was 2.22 l/min (ranged between 1.79 and 2.70 l/min) and the ratio of this to the resting oxygen consumption was 8.31. The peak value of oxygen consumption during uphill walk was 2.73 l/min and the ratio of this to the resting oxygen consumption was 10.39. 4. Energy expenditure during uphill walk showed a mean of 11.1 kcal/min and the peak expenditure rate was 13.6 kcal/min. The total energy expenditure during 36.5 minutes of uphill walk was 396 kcal. 5. In downhill walk, the time was 31.7 minutes, mean heart rate was 118.4 (ranged between 100.1 and 142.7) beats/min, and the peak heart rate was only 129.4 beats/min. The ratio of mean heart rate to the maximal heart rate was 66.3%. Total heart beats during downhill walk was 3,710 beats. The ratio of downhill oxygen consumption to the resting consumption was 5.70. The rate of energy expenditure was 7.5 kcal/min, and the total onery expenditure during the 31.7 minutes of downhill walk was 228 kcal. 6. The effect of training was manifest in the uphill walk and not in the downhill walk. After training in mountain course walk, i) the uphill time was shortened, ii) mean heart rate increased, iii) time vs heart rate curve became smooth and showed less frequent zig-zag, i.e., the depth of trough on the curve decreased and the magnitude was less than 10 beats. In non-trained subject the depth of trough on the curve was greater than 50 beats and appeared more frequently. 7. Mountain climbing is a good health promotion exercise. For the promotion of health the reasonable amount of uphill mountain walk exercise in a 20% grade course is a walk for 40 or 50 minutes duration once a week.

  • PDF

다수 이용자를 위한 동시적 실시간 심박수 모니터링 시스템 (A Simultaneous Real-Time Heart Rate Monitoring System for Multiple Users)

  • 하상호
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
    • /
    • 제4권8호
    • /
    • pp.253-258
    • /
    • 2015
  • u-헬스케어 관점에서 볼 때, 심박수(heart rate)는 아픈 사람의 질환을 관리하는 일리스(illness)나 건강한 사람의 건강을 지속적으로 관리하는 웰니스(wellness) 분야에 모두 유용하게 사용된다. 이는 심박수가 질환의 증상을 판단하거나 운동 부하의 지표로서 모두 사용될 수 있기 때문이다. 최근에 착용형 센서(wearable sensors)를 이용하여 상시적으로 심박수를 모니터링하여 이에 기반하여 현재 몸 상태를 점검해볼 수 있는 다양한 심박계(heart rate monitor)와 이와 연동하여 심박수를 이용한 다양한 운동관리 스마트폰 앱이 개발되어 출시되고 있다. 그러나 이러한 스마트폰 앱은 모두 개인 용도로 제한된다. 논문에서는 여러 사람들의 심박수를 동시에 실시간으로 모니터링할 수 있는 시스템을 설계하고, 이를 적용할 수 있는 안드로이드 앱을 개발한다. 개발된 앱의 주요 기능은 다수 이용자에 대한 동시적 심박수 모니터링으로 피트니스 센터에 효과적으로 적용 가능하다.

북송 이전과 이후 장부도(臟腑圖)의 심장 형태요소의 비교 (Comparison of Form Factors of Heart in ZangFu Diagrams before and after Northern Song Dynasty)

  • 조학준
    • 한국의사학회지
    • /
    • 제30권2호
    • /
    • pp.101-118
    • /
    • 2017
  • Purpose : This paper explores the extent to which ZangFu diagrams made after Northern Song Dynasty were influenced by ZangFu diagrams made before Northern Song Dynasty, and how diagrams of the whole body and heart originated from MingTangZangFuTu and affected each other when quoted in books published after Northern Song Dynasty. Method : The author used four form factors including heart shape, internal curved lines, cylinder-like structures above heart, and wuzangxi (五臟系) which resembles a lotus flower which has not yet bloomed, to analyze and compare different ZangFu diagrams before and after the Northern Song Dynasty. Results : Two form factors, the shape of heart and wuzangxi, are described in ZangFu diagrams before Northern Song, and may have influenced ZangFu diagrams after Northern Song. However, the other two form factors (internal curved lines and cylinder-like structures above the heart) did not influence ZangFu diagrams after Northern Song. All form factors of heart found in WuCangLiuFuZhiTu (within the whole body) and diagram of heart in ZhenJiuJuYing (鍼灸聚英) were most similar, but the two paintings became less similar as they were cited in several books. With the exception of the form factor with structures above heart, the three other form factors are almost identical between two paintings produced after Northern Song dynasty, as displayed in the same book. Conclusion : ZangFu diagrams of the heart produced after Northern Song Dynasty, were not completely based on ZangFu diagrams made before Northern Song Dynasty. Diagrams of whole body and those of the heart were changed, while influencing each other after Northern Song.

청각 자극에 의한 안정화된 심박 패턴 유도 (Auditory impulse by Relaxed on Heart rate Pattern Guidance)

  • 김재경;박민호;장계선;정찬순;고일주
    • 한국HCI학회:학술대회논문집
    • /
    • 한국HCI학회 2008년도 학술대회 1부
    • /
    • pp.158-162
    • /
    • 2008
  • 심박은 주위에 환경적, 신체적, 정신적 상태가 많은 영향을 끼친다. 실험에서 정서를 판단함에 있어서 안정된 상태를 만들어야 정확한 데이타를 얻을 수 있다. 사람은 하루 중 심박수가 시간 및 상태에 따라서 다르다. 그래서 심박수의 안정 상태를 만들어야 한다. 의학에서는 신체적으로 볼 때 낮아지는 심박수일수록 안정 상태이다. 하지안 사람마다 평균 심박수가 다르고 시간마다 심박수 평균이 달라진다. 그래서 심박수로는 안정 심박을 구하기가 힘들다. 심박 패턴을 추출할 때 장기 분석을 통한 검증이 정확하다. 하지만 장기 분석을 하지 않아도 피험자의 안정 상태를 유도 할 수 있다면 장기 분석을 하지 않아도 된다. 안정 심박 패턴을 유도하기 위해서 사용한 청각자극은 우리가 일반적으로 집중력과 스트레스 피로를 해소하는 MC Square와 모차르트 음악을 선정하였다. 두 개의 청각 자극이 안정된 심박을 유도 와 안정된 심박 패턴을 만들 수 있는지를 분석하여 유사점과 차이점을 비교하였다. 본 논문은 분당 심박수 변화와 심박 패턴분석으로 청각자극이 안정된 심박수를 유도하는 유의미한 결과 얻었으며 주위의 영향을 받지 않는 상태 즉, 평상심을 유도 할 수 있었다.

  • PDF

심음에서의 심장판막협착 영역 검출 알고리듬 (Heart Valve Stenosis Region Detection Algorithm on Heart Sounds)

  • 이기현;이윤정;김명남
    • 한국멀티미디어학회논문지
    • /
    • 제15권11호
    • /
    • pp.1330-1340
    • /
    • 2012
  • 본 논문에서는 심음신호를 이용해 강한 심 잡음이 나타나는 심장판막협착 영역을 검출하는 새로운 알고리듬을 제안하였다. 심음의 주성분을 찾거나 심 잡음을 제거하기 위한 지금까지의 많은 연구들은 대동맥판막협착증이나 승모판막협착증과 같이 강한 심 잡음이 나타나는 비정상 심음의 경우, 강한 심 잡음으로 인해 좋은 결과를 보이지 못하였다. 본 논문에서는 구간 잡음강도함수를 이용한 잡음 검출 알고리듬을 제안하였다. 제안한 구간 잡음 강도 함수는 심음 신호에서 제 1심음과 제 2심음을 검출하여, 이를 이용한 심음 구간을 설정한 후 구간 자기상관변화량을 이용하여 도출할 수 있다. 제안한 구간 잡음강도함수를 이용하여 심 잡음의 강도를 판단하고 심 잡음 유무를 검출하였다. 제안한 알고리듬으로 실험한 결과, 심장판막협착 영역 검출에서 기존의 연구보다 뛰어난 성능을 가지는 것을 확인하였다.

심장 상태와 발음간의 연관성 분석을 위한 성대 진동의 변화율 추출 (Change Rate Extraction of Vocal Fold Vibration for Heart Conditional and Pronunciation of Correlative Analysis)

  • 김봉현;조동욱
    • 한국통신학회논문지
    • /
    • 제35권2B호
    • /
    • pp.191-196
    • /
    • 2010
  • 흡연, 당뇨, 비만 및 스트레스 등에 의한 심장 질환이 증가됨에 따라 이로 인한 사망률이 늘어나면서 심장 질환은 현대 사회에서 조기 진단의 필요성을 제시하고 있는 실정이다. 특히 심장 질환에 대한 사람들의 무지와 무관심 때문에 발병율이 급격히 증가하고 있다. 따라서 이와 같은 심장 질환에 대한 사회적 현상을 해결하기 위해 본 논문에서는 동의보감에서 제시하고 있는 심장 상태에 대한 진단 이론을 기반으로 심장 질환의 조기 진단에 필요한 객관적 출력 변수를 설계하였다. 특히 심장 질환에 따른 발음의 부정확성을 입증하기 위해 성대의 진동 변화율을 추출하여 실험 집단간의 비교, 분석을 수행하였다. 이를 위해 본 논문에서는 표준어를 구사하는 성인 남성 중에서 심장 질환을 앓고 있는 환자들과 심장에 이상이 없는 정상인들로 피실험자 집단을 구성하고 이들의 음성을 수집하여 성대 진동의 변화율에 대한 비교, 분석을 통해 심장 질환에 대한 조기 진단 방법을 제안하였다.

개심술 450례의 임상적 고찰 (Clinical Analysis of Open Heart Surgery -Review of 450 Cases)

  • 이서원;이계선
    • Journal of Chest Surgery
    • /
    • 제30권8호
    • /
    • pp.770-779
    • /
    • 1997
  • 본원에서는 1985년 2월 부터 1996년 8월까지 450례의 개심술을 시행하였다. 450례중 선천성 심질환은 222례(49.3%), 후천성 심질환은 228례(50.7%)로 거의 비슷한 비율이었으며, 후반 기 5년간은 후천성 심질환이 더 많았다. 선천성 심질환은 비청색증심질환이 201례, 청색증 심질환이 21례를 차지 하였으며, 수술 사망율은 각각 5.5%와 38.1%를 차지하였다. 청색증 심질환은 대부분 활롯 4징증 이었다. 후천성 심질환 228례중 판막질환은 17례, 허혈성 심질환은 32례, 대동맥 질환은 12례, 심장종양은 6례 있었다. 판막질환은 승모판치환술이 87fll, 대동맥판막 치환술이 45례, 이중판막 치환술이 35례를 차지하였다. 허혈성 심장병의 평균문합순는 2.37개소 였으며, 사망율은 6.3%였다. 판막질환의 사망율은 10.8%, 대동맥질 환의 사망율은 16.7%였다. 전체 사망율은 9.6%이며, 선천성 심질환은 9.0%, 후천성 심질환은 10.1%였다.

  • PDF

뇌성마비아동과 정상아동의 보행전후 산소포화도 및 심박수 비교에 관한 연구 (Comparison of oxygen saturation, heart rate of cerebral palsy and normal child between the pre-ambulation and post-ambulation)

  • 황주문;이완희
    • 대한물리치료과학회지
    • /
    • 제10권1호
    • /
    • pp.38-46
    • /
    • 2003
  • Since the current tendencies show us the increasing number of cerebral palsy children and the standard longevity, we need to find out more research about the following various problems. Therefore I have tried to figure out the difference of oxygen saturation and heart rate between before ambulation and after. Objects chosen are 17 C.P children on the process of treatment those who were able to walk and 8 normal children in Ah-San hospital, Gang-Nung. They haven't had either any operation or suffered heart disease and I measured their oxygen saturation and heart rate by using pulse-oximeter and are analyzed by SPSS (10.07 version). Results are the followings; 1. There was no difference of oxygen saturation and heart rate between pre-ambulation and post-ambulation of normal and spastic hemiplegia children. 2. There showed the significant statistic difference of oxygen saturation, heart rate between pre-ambulates and post-ambulation of normal and spastic diplegia(p<.05). 3. There was no difference of oxygen saturation, heart rate in C.P between(p>.05), but shows the significant statistic difference in heart rate(p<.05). As I compared the oxygen saturation and heart rate of spastic and normal children on between pre-ambulation and post-ambulation, theres is significant statistic difference on both items (p<.05). However there was no difference of oxygen saturation among hemiplegia, normal and diplegia children while the pulse rate showed the significant difference(p<.05). According to this clinical research, CP children's oxygen saturation and heart rate had no change between pre and post compared to normal children. But there was difference in diplegia. This is why we need to invest time to study these kinds of research about various analysis and comparison of oxygen saturation and heart rate, and furthermore making use of pulse-oxymetry in physical therapy room for the children involved would be beneficial to calculate in accuracy without any discomfort for the patient as well.

  • PDF