• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.25 no.1
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• pp.1-11
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• 2012

Objective : Paeoniae radix alba(PRA) can enrich the blood and regulate menstruation, astringe yin and arrest sweating, calm the liver and arrest pain. This study was designed to investigate effects of PRA on skin whitening and elasticity using melanoma cells. Methods : In this experiment, effect of PRA on cell viability, inhibition of melanin synthesis and inhibitory effect on tyrosinase and elastase. Results : 1. More than $1,000\;{\mu}g/ml$ of PRA treated group showed lowered proliferation rates significantly compared to non-treated control group. 2. All of treated groups were lower levels of melanin synthesis respectively. 3. PRA did not show inhibitory effect on tyrosinase activities in vitro. But, PRA suppressed tyrosinase activities in B16F10 cells significantly. 4. PRA suppressed elastse type 1 activities in dose-dependent manner in vitro. But, PRA slightly suppressed elastase type 4 activities in vitro, and PRA also slightly suppressed elastase activities in vivo. Conclusion : These results suggest that PRA can inhibit melanin synthesis through ihhibitory action on tyrosinase activity and inhibt elastase activity, and also suggest that these results can be used for the study on maintaining skin whitening or elasticity.

• Nuclear Engineering and Technology
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• v.46 no.1
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• pp.1-10
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• 2014

Probabilistic risk assessment (PRA) has been used in various technological fields to assist regulatory agencies, managerial decision makers, and systems designers in assessing and mitigating the risks inherent in these complex arrangements. Has PRA delivered on its promise? How do we gage PRA performance? Are our expectations about value of PRA realistic? Are there disparities between what we get and what we think we are getting form PRA and its various derivatives? Do current PRAs reflect the knowledge gained from actual events? How do we address potential gaps? These are some of the questions that have been raised over the years since the inception of the field more than forty years ago. This paper offers a brief assessment of PRA as a technical discipline in theory and practice, its key strengths and weaknesses, and suggestions on ways to address real and perceived shortcomings.

• The Korean Journal of Nuclear Medicine
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• v.10 no.1
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• pp.35-46
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• 1976

To evaluate the possible pathophysiologic role of renin in acute renal failure observed in Korean hemorrhagic fever (KHF), the author measured the basal plasma renin activity (PRA) and the stimulated PRA by radioimmunoassay for angiotensin I in 15 normal controls and 42 KHF patients who are admitted in Seoul National University Hospital and Nation Army Hospital from Jan. 1975 to Jan. 1976. The results obtained were as follows: The mean basal PRA in normal control group was $2.9{\pm}2.16ng/ml/hr$ in the patients during the oliguric phase of KHF, the mean basal PRA was $4.7{\pm}2.13ng/ml/hr$, and there was statistically significant increase compared to the normal control. In the patients during the diuretic phase of KHF, the mean basal PRA was $3.4{\pm}2.09ng/ml/hr$, and there was statistically significant decrease compared to the oliguric phase of KHF. In normal control group, the mean basal PRA was $2.9{\pm}2.16ng/ml/hr$. And the PRA 1 hour after the administration of $Lasix^{(R)}$ 40 mg intravenously(stmulated PRA) was $5.3{\pm}2.20ng/ml/hr$ and there was statistically significant increasec ompared to basal level. In oliguric phase of KHF, the mean basal PRA was $4.6{\pm}2.01ng/ml/hr$. And stimulated PRA was $4.4{\pm}2.34ng/ml/hr$ and there was no significant changes. In diuretic phase of KHF, the mean basal PRA was $3.3{\pm}1.86ng/ml/hr$. And stimulated PRA was 5.2{\pm}2.58ng/ml/hr and there was statistically significant increase compared to basal level. There were statistically no significant correlations between basal PRA and stimulated PRA and serum creatinine, BUN, urine volume and peritonial dialysis.

• The Korean Journal of Nuclear Medicine
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• v.12 no.1
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• pp.9-16
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• 1978

It has been suggested that plasma renin activity (PRA) and its response to volume depletion may be abnormal in that it shows little or exaggerated change in patients with chronic renal failure and hypertension. Intravenous furosemide stimulation test was performed in 46 control subjects and 51 patients with chronic renal failure and/or malignant hypertension in order to evaluate PRA response. In contrast to the consistent increase in PRA in control subjects (from $2.5{\pm}1.95\;to\;4.5{\pm}2.51ng/ml/hr$), no consistent increase was observed in patients with chronic renal failure, especially in those who showed favorable response to antihypertensive therapy (from $2.5{\pm}2.21\;to\;2.9{\pm}2.46ng/ml/hr$). But poor responder to antihypertensive treatment showed considerably higher PRA before and after furosemide stimulation (from $4.9{\pm}1.96\;to\;6.4{\pm}1.71ng/ml/hr$) than the responder group did. Moreover, this group seemed to retain the ability to increase PRA in response to intravenous furosemide stimulation. Thus it became apparent that responder group was unable to increase PRA normally in response to furosemide as well as volume depletion, while poor responder seemed to retain that ability. Thus intravenous furosemode may serve as a convenient way to differenfiate those who might be benefited by conservative antihypertensive measures from those who would require more drastic measures such as bilateral nephrectomy for their optimal blood pressure control.

• The Korean Journal of Nuclear Medicine
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• v.10 no.1
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• pp.1-14
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• 1976

The etiologic role of renin-angiotensin system and sodium-volume status in the pathophysiology of various forms of hypertension was investigated. Plasma renin activity (PRA) was measured by radioimmunoassay, while sodium-volume status was evaluated by the determination of total exchangeable sodium(NaE) using isotope dilution method. The subjects consisted of 25 controls, 24 patients with essential hypertension, with chronic renal failure (13 with hypertension, 9 without hypertension) and with malignant hypertension. The results were as follows: 1. An inverse correlation between NaE and PRA was noted in control subjects (r=-0.598, p<0.001) and normal renin essential hypertension(r=-0.551, p<0.05) and the chronic renal failure with hypertension. (r=-0.790, p<0.001) 2. NaE increased markedly the in chronic renal failure with hypertension ($66.9{\pm}8.69mEq/kg$ of LBM, p<0.001) and the chronic renal failure without hypertension ($54.9{\pm}9.28mEq/kg$ of LBM, p<0.05), while mild increase was noted in malignant hypertension ($51.7{\pm}6.24mEq/kg$ of LBM, 0.05$50.1{\pm}7.24mEq$) as well as in its renin subgroups.(p>0.1) 3. Absolute value of PRA was not deviated significantly from control group ($2.53{\pm}1.416ng/ml/hr$) except in malignant hypertension ($6.09{\pm}2.042$, p<0.001). But PRA was inappropriately high in relation to prevailing NaE in the chronic renal failure with hypertension (eleven of thirteen patients) and malignant hypertension (ten of fourteen patients), while PRA variatiation was within physiologic range in the chronic renal failure without hypertension. 4. The NaE-PRA product was markedly increased in the chronic renal failure with hypertension ($514.4{\pm}42.10$, p<0.001) and in malignant hypertension ($442.7{\pm}55.03$, p<0.001), while moderately increased NaE-PRA product was noted in the chronic renal failure without hypertension ($402.6{\pm}59.67$, p<0.001). No significant difference in NaE-PRA product was noted in essential hypertension ($354.4{\pm}62.38$, p>0.1). It is suggested that renin-angiotensin system plays a predominant role in the pathogenesis of malignant hypertension and in hypertension of chronic renal failure, though sodium retention is also contributing factor. PRA variation in essential hypertension does not appear to be associated with any consistent change in Na-volume status, suggesting the existence of another mechanism in the genesis of hypertension and PRA variation.

• Journal of Preventive Medicine and Public Health
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• v.24 no.4 s.36
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• pp.516-530
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• 1991

A case-control study was conducted to investigate the effect of low-level blood lead on the blood pressure. The plasma renin activity(PRA) was measured also to investigate one of the possible mechanisms by which lead nay play a role to influence on the blood pressure. Seventy-two hypertensive and sixty -nine control study subjects were selected from the workers who had no history of b-related lead exposure, in Ulsan city and it's vicinity, Korea. In addition to measuring blood lead levels and PRA, body mass index(BMI), hematocrit, serum sodium, potassium, creatinine, ionized calcium, and cholesterol were measured. Also, the habits of smoking, alcohol drinking and family history of hypertension were checked. The blood lead level of the hypertensive group was $19.8{\pm}5.5{\mu}g/dl$, which was significantly higher than that of the control group, $12.5{\pm}4.7{\mu}g/dl$(p<0.01). On multiple logistic regression analysis, the odds ratio of blood lead level on the occurence of high blood pressure was 1.38, also statistically significant (p<0.01). There was no significant differences between the hypertensive and the control group in the PRA or In (PRA), but there was a marginally significant linear relationship between blood lead and PRA in the hypertensive group(p<0.1). In conclusion, blood lead level which has been known to be within normal limits may be one of the possible risk factors of hypertension and PRA alteration by lead may act as one of the mechanisms.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.700-707
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• 2010

Effects of protease-resistant antimicrobial substances (PRA) produced by Lactobacillus plantarum and Leuconostoc citreum on rumen methanogenesis were examined using the in vitro continuous methane quantification system. Four different strains of lactic acid bacteria, i) Lactococcus lactis ATCC19435 (Control, non-antibacterial substances), ii) Lactococcus lactis NCIMB702054 (Nisin-Z), iii) Lactobacillus plantarum TUA1490L (PRA-1), and iv) Leuconostoc citreum JCM9698 (PRA-2) were individually cultured in GYEKP medium. An 80 ml aliquot of each supernatant was inoculated into phosphate-buffered rumen fluid. PRA-1 remarkably decreased cumulative methane production, though propionate, butyrate and ammonia N decreased. For PRA-2, there were no effects on $CH_4$ and $CO_2$ production and fermentation characteristics in mixed rumen cultures. The results suggested that PRA-1 reduced the number of methanogens or inhibited utilization of hydrogen in rumen fermentation.

• Herbal Formula Science
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• v.31 no.3
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• pp.183-191
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• 2023

Objective : UVB damages skin health by causing skin redness and intense inflammation, sunburn, and skin cancer. Paeoniae Radix Alba has been used to relieve gynecological symptoms, muscle spasms, and skin ailments. This study was conducted to confirm whether it has a protective effect against UVB photodamage. Methods : Ethanol extract of Paeoniae Radix Alba (PRA) was prepared by extracting 100 g Paeoniae Radix Alba in 1 L of ethanol for 48 h. Apoptosis was monitored by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and expression levels of apoptosis indicator proteins, and tyrosinase activity was measured with a colorimetric commercial kit. Results : In human keratinocyte HaCaT cells, PRA reduced UVB-induced cell death through apoptosis by inhibiting PARP cleavage and caspase-3 and -9. UVB-induced increase in cellular reactive oxygen species (ROS) was suppressed by PRA pretreatment. PRA also showed dose-dependent ABTS and DPPH radical scavenging activities. Furthermore, the inhibitory effect of tyrosinase activity by PRA was confirmed. Conclusion : These results demonstrated the protective role of PRA in UVB photodamage of human keratinocytes, mainly due to its antioxidant and antiapoptotic properties. We also suggest that PRA can be considered as an effective natural agent to prevent skin photodamage.

• The Korean Journal of Nuclear Medicine Technology
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• v.25 no.1
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• pp.29-33
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• 2021

Purpose Plasma renin activity (PRA) test is important for the diagnosis of primary aldosteronism. PRA is an easily deformed substance in vitro and affected by temperature changes. Laboratory of ASAN medical center has consistently found that there was a difference between the initial and re-experimental results. We compared and analyzed the differences in PRA test results according to the sample storage status. Materials and Methods The measurement of PRA was performed by using the radioimmunoassay. From August to September 2020, 43 PRA re-test samples were tested with different sample storage condition. The first group was re-examined by freezing the plasma-separated samples at -18℃, and the second group was re-examined with refrigerated EDTA sample. Also, additional tests were conducted on 13 PRA samples to verify the effect on thawing temperature differences in plasma-separated samples. The same samples were divided into two parts and stored frozen at -18℃, respectively, and thawing samples in room temperature and those in refrigerator were were conducted. Each result was compared and analyzed based on the initial experimental results. Results The results of re-examination after frozen storing plasma separation samples showed a lower correlation than the results of re-examination with EDTA plasma samples in refrigerator. When calculating the percentage based on the initial test results, the average percentage of each was 404.9% and 133.8%. The correlation coefficient was also R=0.8501 and R=0.9966, respectively, showing a higher correlation between plasma in the refrigerated sample EDTA tube. In comparison experiments with differences in thawing temperature, average percentage of the results of initial test and room temperature thawing was 94.3% and the average percentage of the results of refrigerated thawing was 88.0%. After again freezing the sample, the average percentage of the second room temperature thawing result is 107.5%, and the second refrigerated thawing group is 112.7%. Both groups showed an increase from first thawing. Conclusion A comparative analysis of retesting according to differences in sample storage methods in PRA tests showed a higher correlation between the results of retesting of the refrigerated EDTA plasma. And repeated freezing and melting of plasma separation samples, regardless of temperature during defrosting, has been shown to affect results. Therefore, retest of PRA should re-collect plasma from original EDTA plasma to increase reproducibility.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.84-89
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• 2018

Purpose Renin is a proteolytic enzyme synthesized and secreted from epidermal(juxtaglomerular) cells in kidney. Renin acts on the renin substrate angiotensinogen to produce angiotensin I, and then angiotensin II is produced by the action of angiotensin converting enzyme. This causes the adrenal glands to boost blood pressure (vasoconstriction) and promote aldosterone secretion. While Plasma renin activity (PRA) is to test angiotensin I, the active renin concentration (ARC) is a renin test directly. They have different test methods and their own substrates. However, these two methods are sometimes interpreted as the same as a result. The purpose of this study was to evaluate the usefulness of the ARC test by comparing the results between PRA and ARC. Materials and Methods For the diversity of the experiment, 26 samples were requested to test with PRA(TFB company) and ARC(Cisbio company) to other institution. We compared and analyzed PRA(Immunotech company) and ARC(Cisbio company) tests using 28 samples from September $15^{th}$ to October $13^{th}$ in 2017. The statistical analysis method for PRA/ARC evaluated the usefulness using Microsoft Excel program by verifying a correlation analysis of Aldosterone/PRA ratio and a correlation analysis of Aldosterone/ARC ratio and conducting T-test. Results The regression equation of the PRA(Immunotech company)/ARC(Cisbio company), which was tested in the department, was y = 0.0619x + 0.4615 and the correlation coefficient was 0.73. The regression equation of the PRA(TFB company)/ARC(Cisbio company), which was tested in the other institution, was y = 0.0888x + 0.3316 and the correlation coefficient was 0.91. In addition, The regression equation of Aldosterone / PRA ratio and Aldosterone / ARC ratio was y = 0.875x - 11.688 and the correlation coefficient was 0.87. Plus T - test showed no significant difference (P>0.05). Conclusion Both tests showed a strong positive correlation, but this only represents the strength and direction of the relationship between the two tests. Furthermore, the actual results showed somewhat differences. It is presumed that the measured value was influenced by the endogenous renin group mass in the plasma, the condition of the enzyme reaction and the kind of the inhibitor. When the active renin concentration (ARC) test is performed, it is useful to distinguish between the two tests as they are complementary.