• The Korean Journal of Physiology
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• v.18 no.1
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• pp.19-35
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• 1984

Since the first report of Drury and $Szent-Gy{\ddot{o}}rgyi$ in 1929, the inhibitory influences of adenosine on the heart have repeatedly been described by many investigators. These studies have shown that adenosine and adenine nucleotides have overall depressant effects, similar to those of acetylcholine. Heart beats become slow and weak. It is also well known that adenosine is a potent endogenous coronary vasodilator. Many investigations on the working mechanisms of adenosine have been focused mainly on the effects of the coronary blood flow. However, the cellular mechanisms underlying the inhibitory action of adenosine on sinus node are not well understood yet. Thus, this study was undertaken to examine the behavior of rabbit SA node under influence of adenosine. In these series of experiments three kinds of preparations were used: whole atrial pair, left atrial strip, and isolated SA node preparations. The electrical activity of SA node was recorded with conventional glass microelectrodes 30 to 50 $M{\Omega}$. The preparations were superfused with bicarbonate-buffered Tyrode solution of pH 7.35 and aerated with a gas mixture of $3%\;CO_2-97%\;O_2$ at $35^{\circ}C$. In whole atrial pair, adenosine suppressed sinoatrial rhythm in a dose-dependent manner. Effect of adenosine on atrial rate appeared at the concentration of $10^{-5}M$ and was enhanced in parallel with the increase in adenosine concentration. Inhibitory action of adenosine on pacemaker activity was more prominent in the preparation pretreated with norepinephrine, which can steepen the slope of pacemaker potential by increasing permeability of $Ca^{+2}$. Calcium ions in perfusate slowly produced a marked change in sinoatrial rhythm. Elevation of the calcium concentration from 0.3 to 8 mM increased the atrial rate from 132 to 174 beats/min, but over 10 mM $Ca^{+2}$ decreased. The inhibitory effect of adenosine on sinoatrial rhythm developed very rapidly. Atrial rate was recovered promptly from the adenosine-induced suppression by the addition of norepinephrine, but extra $Ca^{+2}$ was less suitable to restore the suppression of atrial rate. Adenosine suppressed also atrial contractility in the same dosage range that restricted pacemaker activity, even in the reserpinized preparation. In isolated SA node preparation, spontaneous firing rate of SA node at $35^{\circ}C$(mean{\pm}SEM, n=16) was $154{\pm}3.3\;beats/min. The parameters of action potentials were: maximum diastolic potential(MDP), $-73{\pm}1.7\;mV: overshoot(OS), $9{\pm}1.4\;mV: slope of pacemaker potential(SPP), $94{\pm}3.0\;mV/sec. Adenosine suppressed the firing rate of SA node in a dose-dependent manner. This inhibitory effect appeared at the concentration of $10^{-6}M$ and was in parallel with the increase in adenosine concentration. Changes in action potential by adenosine were dose-dependent increase of MDP and decrease of SPP until $10^{-4}M$. Above this concentration, however, the amplitude of action potential decreased markedly due to the simultaneous decrease of both MDP and OS. All these effects of adenosine were not affected by pretreatment of atropine and propranolol. Lowering extra $Ca^{2+}$ irom 2 mM to 0.3 mM resulted in a marked decrease of OS and SPP, but almost no change of MDP. However, increase of perfusate $Ca^{2+}$ from 2 mM to 6 or 8 mM produced a prominent decrease of MDP and a slight increase of OS and SPP. Dipyridamole(DPM), which is known to block the adenosine transport across the cell membrane, definately potentiated the action of adenosine. The results of this experiment suggest that adenosine suppressed pacemaker activity and atrial contractility simultaneously and directly, by decreasing $Ca^{2+}-permeability$ of nodal and atrial cell membranes.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.238-243
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• 2009

Background: Radiofrequency obliteration and endovenous laser therapy of the greater saphenous vein have recently been introduced as alternative, minimally invasive techniques for the treatment of saphenous vein incompetence. The 7 Fr. VNUS $ClosureFAST^{(R)}$ radiofrequency obliteration system was introduced in Gwang-Ju Veterans hospital. The purpose of this study is to evaluate the efficacy and complications of radiofrequency obliteration using the 7 Fr. VNUS $ClosureFAST^{(R)}$ system. Material and Method: Between May 2, 2007 and May 31, 2008, we performed radiofrequency obliteration on 90 patients. The number of males was 67 and their mean age was $57.9{\pm}11.0$ (range: $23{\sim}78$) years old. The patients underwent follow up exams at 3 weeks after the procedures and then every 3 months. The effects of treatment and the complications were reviewed. Result: The postoperative complications were ecchymosis (94.4%), pain (27.8%), paresthesia (25.6%), bullous formation (8.9%), edema (6.7%) and phlebitis (2.2%). One patient showed good blood flow after 3 weeks and one patient showed good blood flow after 3 months. The one-year success rate of radiofrequency obliteration in varicose veins was 97.6%. Conclusion: Our data showed acceptable operative results and short-term clinical results for treating varicose veins with radio frequency obliteration. Long-term follow-up and comparison of radio frequency obliteration with high ligation and stripping, previous radiofrequency ablation and endovenous laser therapy are needed in the future.

• Journal of Chest Surgery
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• v.38 no.7 s.252
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• pp.468-475
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• 2005

Transmyocardial revascularization (TMR) in end stage ischemic heart disease results in variable clinical responses. We investigated the acute effect of early reperfusion and the angiogenesis after formation of the transmyocardial channel in a transplanted rat heart model with acute myocardial infarction. Material and Method: In the 30 transplanted hearts we induced acute myocardial infarction by ligating the proximal left coronary artery and inserted a porous 22G intravenous cannula into the left ventricle. After ten minutes of reperfusion, we removed the cannula. At every stage, we recorded the heart rate, QRS size, and left coronary arterial blood flow using the electrocardiogram and Doppler. One week later the rats were sacrificed and evaluated for the patency of intramyocardial channels and the angiogenesis. Result: The heart rates after ligation and after cannula insertion were $239.1\pm61.7,\;235.8\pm58.0bpm$ respectively, and they were statistically significantly slower than that of before ligation, $277.6\pm40.3bpm\;(p=0.017,\;p=0.007\;respectively)$. QRS sizes before ligation, after ligation, and after cannula insertion were $3.6\pm3.3mm,\;2.8\pm3.3 mm,\;and\;2.4\pm2.2mm,$respectively, and there was no significant difference in the three groups. Doppler findings after ligation showed that average peak and mean values of coronary perfusion were significantly decreased from $2.11\pm0.17kHz,\;1.25\pm0.22kHz\;to\;0.83\pm0.15kHz,\;0.38\pm0.11kHz$(p<0.05 respectively). After insertion of the porous cannula, the average peak and mean values of coronary perfusion were $0.61\pm0.05kHz\;and\;0.33\pm0.05 kHz$ respectively, but there was no statistically significant change compared to values after ligation. In all cases except one, pathologic findings showed no patent channels in the acute stage, however, one case showed the angiogenesis. Conclusion: We confirmed that TMR in a rat heart transplant model did not show blood flow through the channel in the acute stage. However, reperfusion effect in some cases had a potential for angiogenesis.

• Childhood Kidney Diseases
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• v.4 no.2
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• pp.127-135
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• 2000

Purpose: Cyclosporine(CsA) is a potent immunosuppressant but the use of CsA is associated with various side effects, especially nephrotoxicity. In tile kidney, salt depletion activates tile renin-angiotensin-aldosteron(RAS) system and accentuates chronic CsA nephropathy. We postulate that angiotensin converting enzyme inhibitors(ACEI) can prevent chronic CsA nephropathy, since ACEI may inhibit this cascades. This study was aimed to assess the effect of ACEI on chronic cyclosporin nephropathy in salt depleted rats. Methods: 36 Fischer-344 rats were divided into 6 goups. Group I received normal salt diet(NSD). Group II received a low salt diet(LSD). Group III received CsA with a NSD. Group IV received CsA with a LSD. Group V received NSD+CsA with ACEI. Group VI received LSD+CsA with ACEI. Rats were sacrificed after six weeks and the glomerular filtration rate(GFR), serum sodium, potassium and whole blood cyclosporine levels were measured. Renal tissues me sampled for the observation of histological changes. Results: No differences in blood CsA level & serum sodium were found between groups during the course of this experiment. Serum potassium in group VI was significantly increased compared with group IV and V (P<0.05). In groups treated with CsA only and in those where CsA was combined with ACEI, GFR was found to be significantly more decreased in LSD than NSD, and GFR in group V was significantly decreased in comparison with group III (P<0.05). Renal histologic lesions associated with CsA which consisted of cortical interstitial fibrosis, tubular atrophy and hyalinization of arterioles were more severe in tile LSD group. But, no differences were observed between tile groups treated with CsA and ACEI, and the groups treated with only CsA. Conclusion: Salt depletion associated with the activation of the RAS system accentuated chronic CsA nephrotoxicity, but, ACEI could not reduce the functional and morphological changes of salt depleted kidneys, in which nephropathy can be exacerbated in spite of the blocking of the angiotensin II pathway. further studies are required to elucidate whether Am ameliorated the effect of salt-depleted CsA nephrotoxicity upon the effective renal blood flow.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.2
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• pp.25-28
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• 2019

Purpose In patients with unusual kidney position after $^{99m}Tc-DTPA$ renal dynamic imaging study, the GFR(Glomerular Filtration Rate) values are significantly different according to the depth of the kidney. Thus, we tried to compare the difference of the GFR values between the depth measurement methods and in-vitro test. 30 adult patients who were subjected to renal study. 27 patients were in usual position and 3 patients were in unusual. $555{\pm}37MBq$ of $^{99m}Tc-DTPA$ was administrated to all patients. GE infinia gamma camera was used. GFR values were obtained in-vivo(gates method) and in-vitro(blood). The kidney depth in-vivo was calculated by three methods(tonnensen, manual, taylor). In-vitro, GFR was performed by blood test. Differences in the mean values of GFR and correlation between depth and GFR values were evaluated using the SPSS 12.0 statistical program. The GFR values for 27 patients with kidney in the usual position are as follows(1.tonnensen 2.manual 3.taylor 4.invitro); $69.3{\pm}4.2$, $88.2{\pm}5.6$, $77.8{\pm}4.3$, $82.2{\pm}5.8ml/min$. The three unusual cases are as follows, first(congenital renal anomaly): 66.4, 101.24, 69.07, 94.8 ml/min. second(transplantation kidney): 12.22, 29.99, 19.36, 23.5 ml/min. third(horseshoe kidney): 37.37, 93.54, 35.9, 92.5 ml/min. There was a difference between tonnensen and manual in the usual position of the kidney(p<0.05). There was no significant difference between the other methods. However, there was a significant difference in case of the unusual position of the kidneys. Correlation analysis between both kidney depth and GFR value shows person correlation as follows; Rt kidney: 0.298, Lt kidney: 0.322. When compared with the GFR values in-vitro test, it was useful to calculate the GFR value by measuring the kidney depth using a manual formula in the unusual position of the kidneys. GFR values and kidney depth were significantly related.

• Tuberculosis and Respiratory Diseases
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• v.52 no.5
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• pp.529-538
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• 2002

Background : Many clinicians are reluctant to prescribe systemic corticosteroids to manage an asthmatic attack because of many complications such as osteoporosis, cushing's syndrome, diabetes, hypertension and bleeding tendency. The use of nebulized budesonide may be of value in some infants, old men, and in particular adult asthmatic patients who complain of severe dyspnea. A clinical validation and steroid-sparing effect of nebulized budesonide in asthmatic adults and COPD were evaluated, and the short-term effects of budesonide use on the HPA axis were assessed. Materials and Methods : Study A was prospectively done with 41 patients diagnosed with pure asthma and 30 patients diagnosed with COPD (including asthmatic component) in Soonchunhyang Hospital, Chunan from June. 2000 to Sep. 2001. They were treated with nebulized budesonide including systemic steroids (Group 1), a budesonide tubuhaler including a systemic steroid (Group 2), or only the systemic steroid(Group 3). The peak flow rate, arterial blood gas in room air, pulmonary function test, symptom scoring, steroid amount and hospital stay were analyzed. Study B was conducted with 19 patients to evaluate the short-term effects on the HPA axis of treatment with nebulized budesonide 1mg twice daily and a budesonide turbuhaler 5 puffs twice daily. The adrenal function was assessed prior to budesonide inhalation and after 7 days of budesonide inhalation. Results : In the pure asthmatic patients, the mean value of the symptoms (dyspnea, wheezing, cough, night asthma) or the arterial BGAs, total amounts of steroid or hospital stay and the difference in the results of the pulmonary function tests or peak expiratory flow rate were similar in the three groups. In COPD with an asthmatic component, there were no significant differences among the three groups. Although nebulized budesonide suppressed HPA function,(p=0.006) the HPA responses from the nebulized budesonide and turbuhaler budesonide were similar (p=0.288) Conclusion : This result suggests that systemic steroid should only be made available for acute asthmatic patients irrespective of the inhaled budesonides. Nebulized budesonide at the therapeutic dose has similar effects on the HPA axis compared to that of turbuhaler budesonide.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.151-160
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• 1998

Tangerine peel is mostly discarded as waste in citrus processing. However, tangerine peel contains besides dietary fibers bioflavonoids such as naringin and hesperidin which act as antimicrobials and blood pressure depressants, respectively. A continuous membrane separation process was optimized for the production of bioflavonoids relative to feed flow rate, transmembrane pressure, temperature, and pH. The tangerine peel was blended with 7.5 times water volume and the extract was prefiltered through a prefiltration system. The prefiltered extract was ultrafiltered in a hollow fiber membrane system. The flux and feed flow rate didn't show any apparent correlation, but we could observe a mass-transfer controlled region of over 8 psi. When temperature increased from $9^{\circ}C\;to\;25^{\circ}C$, the flux increased about $10\;liters/m^2/min\;(LMH)$ but between $25^{\circ}C\;and\;33^{\circ}C$, the flux increased only 2 LMH. At every transmembrane pressure, the flux of pH 4.8 was the most highest and the flux at pH 3.0 was lower than that of pH 6.0, 7.0, or 9.0. Therefore, the optimum operating conditions were 49.3 L/hr. 10 psi, $25^{\circ}C$, and pH 4.8. Under the optimum conditions, the flux gradually decreased and finally reached a steady-state after 1 hr 50 min. The amount of dietary fibers in 1.0 g retentate in each separation step was analyzed and bioflavonoids concentration in each permeate was measured. The contents of total dietary fiber in the 170 mesh retentate and soluble dietary fiber in the prefiltered retentate were the highest. Naringin and hesperidin concentration in the permeate were $0.45{\sim}0.65\;mg/g\;and\;5.15{\sim}6.86\;mg/g$ respectively, being $15{\sim}22$ times and $79{\sim}93$ times higher than those in the tangerine peel. Therefore, it can be said that PM 10 hollow fiber membrane separation system may be a very effective method for the recovery of bioflavonoids from tangerine peel.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.628-635
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• 1999

Background : Maximal expiratory flow rate is determined by the size of airway, elastic recoil pressure and the collapsibility of airway in the lung. The obstruction of expiratory flow is one of the major functional impairments of emphysema, which represents COPD. Nevertheless, expiratory narrowing of upper airway may be recruited as a mechanism for minimizing airway collapse, and maintaining lung volume and hyperinflation by an endogenous positive end-expiratory pressure in patients with airflow obstruction. We investigated the physiologic role of trachea in respiration in emphysema. Method : We included 20 patients diagnosed as emphysema by radiologic and physiologic criteria from January to August in 1997 at Seoul Municipal Boramae Hospital. Chest roentgenogram, high resolution computed tomography(HRCT), and pulmonary function tests including arterial blood gas analysis and body plethysmography were taken from each patient. Cross-sectional area of trachea was measured according to the respiratory cycle on the level of aortic arch by HRCT and calibrated with body surface area. We compared this corrected area with such parameters of pulmonary function tests as $PaCO_2$, $PaO_2$, airway resistance, lung compliance and so on. Results : Expiratory cross-sectional area of trachea had significant correlation with $PaCO_2$ (r=-0.61, p<0.05), $PaO_2$ (r=0.6, p<0.05), and minute ventilation (r=0.73, p<0.05), but inspiratory cross-sectional area did not (r=-0.22, p>0.05 with $PaCO_2$, r=0.26, p>0.05 with $PaO_2$, and r=0.44, p>0.05 with minute ventilation). Minute ventilation had significant correlation with tidal volume (r=0.45, p<0.05), but it had no significant correlation with respiratory frequency (r=-0.31, p>0.05). Cross-sectional area of trachea had no significant correlation with other parameters of pulmonary function including $FEV_1$, FVC, $FEV_1$/FVC, peak expiratory flow, residual volume, diffusing capacity, airway resistance, and lung compliance, whether the area was expiratory or inspiratory. Conclusion : Cross-sectional area of trachea narrowed during expiration in emphysema, and its expiratory area had significant correlation with $PaCO_2$, $PaO_2$, and minute ventilation.

• Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.65-69
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• 2005

We evaluated the effects of the partial dietary replacement of fish meal with squid liver $Meal^{TM}$ on the growth and body composition of juvenile olive flounder Paralichthys olivaceus during the winter season. Twenty-five fish with an initial body weight of 23 g per tank were distributed among 12,250 L flow-through tanks. The experimental diets, which were designated SLM5, SLM1O, and SLM15 diets, were prepared in triplicate along with control diet by replacing 5, 10, and $15\%$ of mackerel fish meal with squid liver $Meal^{TM}$, respectively. The weight gain and specific growth rate of flounder that were fed the control and SLM5 diets did not differ from those of the fish fed the SLM10 diet, but they were significantly (P<0.05) higher than those of the fish fed the SLM15 diet. The feed efficiency ratios for the flounder that were fed the control, SLM5 and SLM10 diets were significantly (P<0.05) higher than for the fish that were fed the SLM15 diet. However, the protein efficiency ratio for the flounder was not significantly affected by the experimental diets. The crude protein, crude lipid and ash content, and blood chemistry of the flounder were not significantly affected by the experimental diets. Therefore, the replacement of up to $10\%$ of dietary fish meal with squid liver $Meal^{TM}$ can be made without a reduction in growth or a deterioration of the feed efficiency of juvenile olive flounder during the winter season.

• Archives of Plastic Surgery
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• v.37 no.3
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• pp.227-232
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• 2010

Purpose: Continuous irrigation method is an important step in managing wound infection. V.A.C. devices have been used in intractable wounds for reducing discharge, improving local blood flow, and promoting healthy granulation tissue. We expect synergistic effects of reduced infection and more satisfactory, accelerated wound healing when using both methods simultaneously. This study evaluated continuous irrigation combined with V.A.C. appliance for treatment of infected chronic wounds. Methods: We reviewed data from 17 patients with infected intractable chronic wounds. V.A.C. device (Group A) was used in 9 patients, and V.A.C. with antibiotics irrigation (Group B) was used in 8 patients. We placed Mepitel$^{(R)}$ on the surface of wound and placed an irrigation and aspiration tube on each side. A sponge was placed on the Mepitel$^{(R)}$ and covered with film dressing. The wound was irrigated continuously with mixed antibiotics solution at the speed of 200 cc/hr and aspirated through the wall suction at the pressure of -125 mmHg. V.A.C. applied time, wound culture and wound size were compared between the two groups. Results: No complication were seen in two groups. Compared with Group A, in the Group B, V.A.C. applied time was shortened from 32.7 days to 25.6 days and showed efficacy in the reduction rate of wound size. No statistical differences were shown in bacterial reversion. Conclusion: V.A.C. appliance with continuous irrigation is an effective new method of managing infected chronic wounds and useful to reduce treatment duration and decrease wound size. Moreover it could be applied more widely to infected wound.