• Journal of Biomedical Engineering Research
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• v.35 no.4
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• pp.95-98
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• 2014

The baroreflex is one kind of homeostatic mechanisms to regulate acute blood pressure (BP) changes by controlling heartbeat interval (HBI). To quantify the effect of baroreflex, we suggested a new approach of analyzing Granger causality between systolic BP (SBP) and HBI. The index defined as baroreflex effectiveness (BRE) was generated by the hypothesis that more effectual baroreflex would be related to more effective Granger causal influence of SBP on HBI. Six obstructive sleep apnea (OSA) patients (apnea-hypopnea index, AHI ${\geq}5$ events/hr) and six normal subjects participated in the study. Their SBP and HBI during nocturnal sleep were obtained from a non-invasive continuous BP measurement device. While the BRE ($mean{\pm}SD$) of normal subjects was $47.0{\pm}4.0%$, OSA patients exhibited the BRE of $34.0{\pm}3.8%$. The impaired baroreflex function of OSA patients can be explained by the physiological mechanism associated with recurrent hypoxic episodes during sleep. Thus, the significantly lower BRE in OSA patients verified the availability of Granger causality analysis to evaluate baroreflex during sleep. Furthermore, the range of BRE obtained from normal subjects was not overlapped with that obtained from OSA patients. It suggests the potential of BRE as a new helpful tool for diagnosing OSA.

• Journal of Biomedical Engineering Research
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• v.41 no.1
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• pp.8-13
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• 2020

To develop cardiovascular simulator capable of implementing pulse waves similar to the human body, accurate information about reflection wave is required. However, the conclusion is still not clear and various discussions are underway. In this study, the pulse wave velocity of the tube used in the experiment was first determined by measuring the pressure waves at two points in a single tube system with the experimental device to implement the pulse wave transmission of blood vessels, and the superposition time and characteristics of the reflection wave were confirmed. After that, an air chamber was set at the reflection site, and the effect of the change of air volume on the reflection wave was investigated. Finally, the effect of the number of branches connected to a single tube on the reflection wave was investigated. The superposition time of the reflection wave can be controlled by the air volume of the air chamber, and the magnitude of the reflection wave is influenced by the number of reflection sites that generate the reflection wave. The results of this study may be of practical assistance to simulator researchers who want to implement pulse wave similar to clinical data. It is expected that the more results similar to clinical are provided, the greater the scope of the simulator's contribution to clinical cardiovascular research.

• Quality Improvement in Health Care
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• v.3 no.1
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• pp.126-143
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• 1996

Background : Little work has been carried out regarding quality assessment research in a primary care setting, comparing with that of hospitals. This study aims to evaluate the process of diagnosis and management of hypertension by public health doctors on the basis of pre-established clinical guideline, and to identify several modifying factors associated with them. Methods : Hypertension was selected as the target disease, because it is a chronic disease which is of great public health importance. Self-administered questionnaires were mailed to public health doctors practicing at health centers and health subcenters across the nation. The response rate was 20.9%. The questionnaire included the diagnosis and management process such as measuring blood pressure, history taking, physical examinations, and treatment approches and potentially modifying factors such as level of training, duration of practice as a public health doctor, and education on management of hypertension. Results : Public health doctors pay little attention in measuring BP, hypertension related history taking, performing physical examination and laboratory examination. But they devoted much effort in diagnosing hypertension exactly and giving nonpharmacological treatment. Among various antihypertensive drugs, calcium-channel blockers were the most preferred agent(50.9%). Level of training, duration of practice ad a public health doctor, and education on management of hypertension made no difference on quality of care(p>0.05). Conclusion : These public health doctors showed poor compliance with the pre-established clinical guidelines, which leaves much to be desired in diagnosing and managing hypertensive patients by public health doctors. This study might be able to contribute to develop some strategies, such as educational programs, which would be able to improve the process of care in hypertensives.

• The Korean Journal of Physiology
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• v.19 no.2
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• pp.189-202
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• 1985

Enhanced activity of renin-angiotensin-aldosterone system has been suggested as a cause of the high blood pressure in certain forms of experimental hypertension. In spontaneously hypertensive rats, however, increased activity of the system has not been found, and even suppressed renin angiotensin system has been reported in the spontaneously hypertensive rat. In the present experiments it was attempted to explore the possible alteration of the short loop negative feedback control in the hypertensive rat. Experiments have been done in the anesthetized spontaneously hypertensive rats(SHR) as well as in normotensive Wistar and Sprague Dawley rats as control. Responses of the plasma renin activity to the intravenous L-isoproterenol were dose dependent, in both SHR and normotensive control rats. Hypotensive responses to smaller do sea of L-isoproterenol were more accentuated in SHR than in the normotensive control rats. Angiotensin If given intravenously suppressed plasma renin activity in a dose dependent fashion in both groups. However, these suppressive responses were significantly attenuated in SHR as compared with the normotensive control rats. Treatment with angiotensin I-converting enzyme inhibitor did not correct the attenuated responses of the plasma renin activity to angiotensin II in SHR. Intravenous infusion of arginine vasopressin also produced a dose-dependent suppression of plasma renin activity in both groups. The responses to arginine vasopressin were also significantly attenuated to the normotensive control rats. In the sodium-depleted SHR, arginine vasopressin did not suppress plasma renin activity, whereas the suppressive responses to arginine vasopressin in the normotensive control rats were not different from the untreated control rats. These data suggest that there may be a derangement in the short loop negative feedback control of the renin-angiotensin system in spontaneously hypertensive rat.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2001.12a
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• pp.69-73
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• 2001

Two opioid peptides, YPLDL and YPLDLF, were isolated from enzymatic digests of spinach ribulose-1, 5-bisphosphate carboxylase/oxygenase (RuBisCO) and named rubiscolin-5 and -6, respectively. These peptides were selective for delta-receptor and the latter was about 3 times more potent than the former. After oral administration in mice at the dose of 100 mg/kg, rubiscolin-6 showed analgesic activity in tail pinch test. It also stimutated learning performance at the same dose in passive avoidance experiment using step-through apparatus. An immunostimulating peptide, MITLAIPVNKPGR, was isolated from a trypsin digest of soybean protein and named soymetide. Immunostimulating activy of soymetide was mediated by fMLP receptor. Interestingly, after oral administration in rats at a dose of 300 mg/kg (po.), soymetide-4 (MITL) protected alopecia (hair-loss) induced by etoposide, a cancer chemotherapy agent. Stimulation of IL-1 release by the peptide was involved in the mechanism. Ovokinin(2-7), RADHPF, is a vasorelaxing peptide released from ovalbumin by the action of chymotrypsin. It lowered blood pressure of spontaneously hypersensive rats (SHR) after oral administration at a dose of 10 mg/kg. RPLKPW, which was designed by replacing 4 amino acid residues in ovokinin(2-7), exhibited hypotensive activity at a dose of 0.1 mg/kg (po.). This peptides was introduced into 3 homologous sites in soybean beta-conglycinin alpha' subunit by site-directed mutagenesis of the cDNA and expressed in E. coli. The minimum effective dose for hypotensive activity of the genetically modified beta-conglycinin alpha' subunit was 10 mg/kg (po.), which is about 1/200 that of ovalbumin.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.146-156
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• 2008

The enhancement of the human body fat reduction of conjugated linoleic acid (CLA) with the supplementation of $\gamma$-oryzanol (OZ) was investigated on overweight Korean women (n=51, BMI> 23). Subjects were divided into 4 groups of control, CLA, glyceride form of CLA (GCLA), and CLA plus OZ (CLA-OZ). The soft-gel capsule (500 mg) was used to deliver control (500 mg olive oil), CLA (500 mg CLA), GCLA (500 mg GCLA) and CLA-OZ (500 mg CLA plus 50 mg OZ). Three capsules were taken twice a day for 12 weeks. The CLA-OZ supplementation reduced 1.35% body fat that was 0.34% enhancement against CLA supplementation. As considered subject variations, CLA-OZ reduced body fat ranged from 7.9% to -2.7%, equivalent to 5.6 kg loss to 0.7 kg gain in body fat mass, against CLA. The CLA-OZ reduced body weight and body mass index (BMI), relative to control, but the reductions by CLA-OZ were not different from those by CLA and GCLA. All biochemical markers analyzed for safty were not significantly different within or between groups and were within the normal range. The CLA-OZ supplementation significantly reduced blood pressure, as compared to the supplementation of CLA, GCLA and control. These results suggest that OZ could be a useful ingredient to mix with CLA for the reduction of human body fat.

• Journal of Convergence for Information Technology
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• v.10 no.11
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• pp.240-250
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• 2020

The purpose of this study was to investigate the relationship between serum uric acid levels, insulin resistance and components of metabolic syndrome. It was conducted on 4,428 adults over the age of 20 who had undergone health checkups at a general hospital in Gyeonggi-do from June 2018 to May 2020. As a result of the study, uric acid levels were higher in the metabolic syndrome subjects than normal subjects in both men and women. and the incidence of metabolic syndrome and its components was higher in the hyperuricemia group than in the normal group. Hyperuricemia was found to increase the risk of elevated blood pressure(p=0.006) and hypertriglyceridemia(p<0.001) in men and metabolic syndrome(p=0.012) and low HDL-cholesterol(p<0.001) in women. Thus, in both men and women, hyperuricemia was associated with metabolic syndrome and its components, and it was confirmed that it was an independent predictor of the onset of metabolic syndrome in women.

• Archives of Pharmacal Research
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• v.19 no.5
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• pp.390-395
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• 1996

To investigate whether $AT_{1}$ receptor antagonists are acting by increasing endothelium-de-pendent and -independent relaxation of aortas in normotensive rats, $AT_{1}$ receptor antagonists, losartan and KR-30988, and angiotensin converting enzyme inhibitor, captopril, were orally administered for two weeks (50 mg/kg, b.i.d.). THe blood pressure, heart rate and body weight were not significantly changed by losartan, KR-30988 and captopril compared to the control group. In aortic preparations, the $pD_{2}$ of KR-30988 for ACh-induced relaxation was 8.33 $\pm$ 0.16, significantly (p <0.05) lower than that of control group $(7.71 \pm 0.15)$. ACh-induced relaxation was significantly increased on losartan-treated group (p<0.01) at $10^{-6}$ M of ACh, and in captopril-treated group (p<0.05) at the range of $10^{-7}$ -$10^{-5}$ M of ACh. The $pD_{2}$ values for histamine-induced relaxatio of losartan, KR-30988 and captopril were 5.57 $\pm$ 0.10, 5.85 $\pm$ 0.21 and 5.60 $\pm$ 0.01, respectively, with significant differences in all groups (p<0.01) compared to that of control group (5.13 $\pm$ 0.09). ACh-induced relaxations of aortic preparations were not changed by pretreatment of indomethacin ($10_{-5}$ M), and completely bolcked by pretreatment of L-NAME $(10_{-5}M)$ in all groups. Sodium nitroprusside-induced relaxations were not significantly changed by all drugs tested in this experiments. These results suggest that $AT_{1}$ receptor antagonists, losartan and KR-30988, enhance the endothelium-dependent relaxatio on aortic preparations through the release of, or increase sensitivity, to nitric oxide in nor-motensive rats.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.2
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• pp.221-232
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• 1997

This study is investigate the eating behavior between the elderly living at home and the elderly at nursing home in Inchon City. This survey was carried out by questionaires. The result are summarized as the followings: 1. Both the elderly living at home and the elderly at nursing home are not smoking and drinking. They are in good health. 2. The elderly living at home and the elderly at nursing home have diseases like neuralgia, hypertension, diabetes etc. 3. Both the elderly living at home and the elderly at nursing home have methods of health care of a regular eating and a good sleeping. The elderly at nursing home have a regular medical examination but the elderly living at home do not. 4. Health giving drugs are depression of blood pressure, a medicine for the stomach and bowels, an anodyne. And health giving sports are walking and jogging. 5. The elderly living at home and the elderly at nursing home are significant relationship on knowledge of nutrition. 6. The elderly living at home and the elderly at nursing home prefer to taste sweet, boiling, korean foods. 7. elderly living at home have meats once a week and the elderly at nursing home have twice a week. Both the elderly living at home and the elderly at nursing home have fish, fruits, vegetables twice a week. The elderly at nursing home have milks twice a week. 8. The frequency of snack intake is higher the elderly at nursing home than the elderly living at home. 9. The elderly living at home and the elderly at nursing home are satisfied their dietary life.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.5 no.1
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• pp.18-22
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• 2009

A 26-year-old female patient with Down syndrome visited to recieve dental treatment under gnenral anesthesia 6 years ago. The patient had difficulties in oral examination, radiograph taking and laboratory test. The patient had congenital heart disease and medical consultation based on the echocardiography was provided by a cardiologist indicating that the patient could tolearte general anesthesia during dental treatment. And two times of general anesthesia were administered during a dental treament with the interval of 3 years and no postoperpative complicaton was reported. At the third dental operation, the patient had a relatively good condition and her prescreening test revealed no abnormalities. Without further consultation with a cardiologist, general anesthesia was administered to the patient. Anaesthesia was based on thiopental and ventilation of desflurane and $N_2O$ in oxygen via an endotracheal tube with an appropriate monitoring. During the maintenance of anesthesia, the blood pressure of the patient started to drop and the oxygen saturation also began to decrease. Consequently, the proceding operation was discontinued and also inhalation anesthesia was ceased. As the patient was recovered from anesthesia, her systemic conditions were alleviated. After the complete recovery of the patient, she visited the cardiologist, and the cardiologic test revealed her severe right ventricular dilatation. In the anesthesia of patients with congenital heart disease, information on their systemic conditions needs to be undated from the medical consultation, which assures the safety of treatment.