• 한국패류학회지
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• 제25권1호
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• pp.15-22
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• 2009

Because it is known that bivalve hearts contain various modulatory systems activated by neuroendocrine substances, it was examined whether different classes of endogenous and synthetic drugs of neuroendocrinological importance can influence cardiac functions of the Pacific oyster Crassostrea gigas. Cholinergically active agents acetylcholine and carbachol increased heart rates while diminishing cardiac contractility. Adrenergically active substances norepinephrine (NE) and epinephrine (Epi) also induced heart rate increase and contractility decrease. An $\alpha_1$-adrenergic receptor-selective agonist phenyephrine (PE) failed to modulate either parameter. The Epi-induced heart rate increase and contractile depression were both blocked significantly by non-selective $\beta_1/\beta_2$-adrenergic antagonist propranolol. A $\beta_1$-selective antagonist atenolol prevented Epi-induced heart rate decrease but not the contractile depression, suggesting possible $\beta_2$ receptors for Epi-induced contractile depression. The three autacoids examined exerted discrete responses: histamine increased heart rate and depressed contraction; $\gamma$-amino-butyric acid increased both parameters; serotonin failed to change either parameter. The 5 piscine anesthetic agents examined, MS-222, benzocaine, quinaldine, urethane, pantocaine and pentobarbital, all failed to influence the cardiac function of oysters. Collectively, activities of neuroendocrinologically acting agents in mammals showed unexpected and distinct activities from those in mammalian cardiovascular systems. These results obtained from substances of different physiological functions can serve as a basis for understanding neuroendocrine control of the heart function in Pacific oyster.

• Journal of Acupuncture Research
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• 제23권1호
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• pp.135-143
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• 2006

Objectives : This study was performed to observe effect of acupuncture stimulation on heart rate variability in stroke patients. Methods : Data were obtained from heart rate variability of 29 stroke patients. Heart rate variability was measured total five times(before and after needle insertion, before and after needle removal, and 10 minutes after needle removal) for five minutes each time. Results : Heart rates were continuously decreased until 10 minutes after needle removal. SDNN, Total power, LF, and HF were increased until 5 minutes after needle removal, but deceased between 5 and 10 minutes after needle removal. There was no significant changes between male and female and among age groups. Conclusion : This study showed that acupuncture stimulation could effect on heart rate variability in stroke patients. Heart rate variability could be a objective tool to verify the mechanism of acupuncture effect in various condition.

• 산업경영시스템학회지
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• 제27권3호
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• pp.90-96
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• 2004

The objective of this study was to develop a model for safe work load based on a physiological model of metabolic energy of manual material handling tasks. Fifteen male subjects voluntarily participated in this study. Lifting activities with four different weights, 0, 8, 16, 24kg, and four different working frequencies (2, 5, 8, 11 lifts/min) for a lifting range from floor to the knuckle height of 76cm were considered. Oxygen consumption rates and heart rates were measured during the performance of sixteen different lifting activities. Simplified predictive equations for estimating the oxygen consumption rate and the heart rate were developed. The oxygen consumption rate and the heart rate could be expressed as a function of task variables; frequency and the weight of the load, and a personal variable, body weight, and their interactions. The coefficients of determination ($r^2$) of the model were 0.9777 and 0.9784, respectively, for the oxygen consumption rate and the heart rate. The model of oxygen consumption rate was modified to estimate the work load for the given oxygen consumption rate. The overall absolute percent errors of the validation of this equation for work load with the original data set was 39.03%. The overall absolute percent errors were much larger than this for the two models based on the US population. The models for the oxygen consumption rate and for the work load developed in this study work better than the two models based on the US population. However, without considering the biomechanical approach, the developed model for the work load and the two US models are not recommended to estimate the work loads for low frequent lifting activities.

• The Korean Journal of Physiology
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• 제3권2호
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• pp.25-31
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• 1969

Effects of graded increase of positive lung inflation upon heart rates and arterial blood pressure were observed in the anesthetized dogs to analyze the mechanical and neural regulatory factor in response to the positive inflation of the lung. The results obtained were summarized as followings: 1) When the low grade of positive lung inflation was employed under the mild to moderate anesthesia, central venous pressure was linearly increased while heart rate was decreased. After bilateral vagotomy, central venous pressure was obviously increased while heart rate was constant. 2) When the high degree of positive lung inflation was employed, changes of central venous pressure and heart rate were not significant. 3) The low grade of intrapulmonary pressure increase caused reflex tachycardia in phase 2 and overshooting in phase 4 in response to the systemic arterial blood pressure change. 4) On the other hand, the high degree of intrapulmonary pressure increase caused paradoxical bradycardia in phase 2 and lack of overshooting in phase 4 in response to the systemic arterial blood pressure change. 5) It may be noted that the experimental model employed in the present study is a useful tool to evaluate and analyze the neural and mechanical regulatory factor in response to the graded increase of the positive lung inflation.

• 한국임상수의학회지
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• 제40권6호
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• pp.464-467
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• 2023

The autonomic regulation of heart rate (HR) is an indicator of the body's ability to adapt to an exercise stimulus. However, there are no reports on this topic in relation to Jeju horses used for racing. The aim of this study was to analyze the HR responses of Jeju horses during race trials and to investigate the correlation between HR and performance in these horses. HR data were collected from 17 healthy 2- to 7-year-old Jeju horses wearing HR monitors during race trials. Pearson correlation coefficients was used to determine the significance of the association between the race trial time and HR. A significant inverse correlation was observed between the race trial time (performance) and both the maximal HR (HRmax, r = -0.69, p < 0.01) and HR reserve (HRR) (HRmax - average HR during the warm-up period, r = -0.63, p < 0.01) and between the HRR and HRmax (r = 0.73, p < 0.01). Horses with a lower average HR during the warm-up period and higher heart rates during the trial achieved faster race trial times. This study reports the first HR measurements in Jeju horses during race trials, providing new insights into the HR response of this breed to exercise. The use of a noninvasive remote HR monitor system allowed assessment of exercise responses in the field, and the results suggest that both the HRR during warm-up period and HRmax may be useful performance indicators in Jeju horses.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1994년도 춘계학술대회
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• pp.72-74
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• 1994

This paper describes the effect of autonomic nervous activity on Heart rate variability and peripheral blood pressure with power spectral analysis and its characteristics of chaotic attractors. The aim of this paper is to access the applicability of spectral and dimension analysis of heart rate variability and peripheral blood pressure, attributed to changes in autonomic nervous system activity. About 60 mininutes of Heart rates and synchronized peripheral blood pressure were recorded on 10 healthy man while various mental and physical conditions. The results shows the availability to evaluate the autonomic nervous activities.

• 약학회지
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• 제51권5호
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• pp.336-342
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• 2007

Treatment of hypertension is important in reducing death and attack rates by Ischemic heart disease (IHD). The purposes of this study are to investigate recent prescriptions for patients with IHD and to evaluate antihypertensive drug use. On the basis of the guidelines proposed by Seventh Report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure, we analyzed prescriptions of antihypertensive drugs for patients with IHD. It is necessary to set up new guideline for appropriate treatment to lower death and attack rates for patients with IHD.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권4호
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• pp.306-312
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• 2010

Purpose: The purpose of this experiment was to evaluate the clinical effect of cultured autoglogous osteoblasts as a way to treat the defect of mandible in rabbits. Materials and Methods: Twelve rabbits were used to determine the rate of osteogenesis. The osteoblasts were obtained from the iliac crest of rabbits using aspiration. They were then cultured in Dulbecco's Modified Eagles's Medium (DMEM) with beta-glycerophosophatate, L-ascorbicacid, and dexamethasone to proliferate and differentiate osteoprogenitor cells. The expression of osteogenic markers were detected by reverse transcription-polymerase chain reaction (RT-PCR) and silver nitrate staining techniques. Five, 10-mm holes were placed in each rabbit mandible to simulate defective regions with the use of a low speed trephine bur. In the experimental group, the previously cited defects were grafted with both activated osteoblastic and autogenous bone. The control group, however, was only grafted with autogenous bone. Both groups were then analyzed at 2, 4, and 8-week intervals using bone histomorphometric analysis. Results: According to histomorphologic analysis, the rates of new bone formation at the 2, 4, and 8-week intervals were 36%, 51%, and 23% for the control group, respectively; 52%, 39%, and 28%, for the experimental group, respectively. The experimental group showed higher rates of new bone formation compared to the control group at both the 2-week and 8-week interval. Conclusion: Bone marrow-derived osteoblasts seems to be a promising bone graft material.

• Clinical and Experimental Pediatrics
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• 제60권8호
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• pp.237-244
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• 2017

During the last 10 years, there have been major technological achievements in pediatric interventional cardiology. In addition, there have been several advances in cardiac imaging, especially in 3-dimensional imaging of echocardiography, computed tomography, magnetic resonance imaging, and cineangiography. Therefore, more types of congenital heart diseases can be treated in the cardiac catheter laboratory today than ever before. Furthermore, lesions previously considered resistant to interventional therapies can now be managed with high success rates. The hybrid approach has enabled the overcoming of limitations inherent to percutaneous access, expanding the application of endovascular therapies as adjunct to surgical interventions to improve patient outcomes and minimize invasiveness. Percutaneous pulmonary valve implantation has become a successful alternative therapy. However, most of the current recommendations about pediatric cardiac interventions (including class I recommendations) refer to off-label use of devices, because it is difficult to study the safety and efficacy of catheterization and transcatheter therapy in pediatric cardiac patients. This difficulty arises from the challenge of identifying a control population and the relatively small number of pediatric patients with congenital heart disease. Nevertheless, the pediatric interventional cardiology community has continued to develop less invasive solutions for congenital heart defects to minimize the need for open heart surgery and optimize overall outcomes. In this review, various interventional procedures in patients with congenital heart disease are explored.

• 대한흉부심장혈관외과학회:학술대회논문집
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• 대한흉부외과학회 1996년도 제 28차 추계학술대회 및 총회 대한흉부외과학회
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• pp.21-21
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• 1996