• Polymer(Korea)
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• v.32 no.6
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• pp.509-515
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• 2008

The aminated polypropylene melt blown ion exchange fibers were synthesized with acrylic acid monomer onto polypropylene melt blown fibers by radiation-induced polymerization and subsequent amination. Degree of grafting was increased with increasing the acrylic acid monomer concentration and total dose. The highest degree of grafting was obtained 140% at a monomer concentration of 20 v/v% acrylic acid and total dose of 4 kGy. Optimum condition of Mohr's salt was 5.0 $\times10^{-3}$ M. Degree of amination was increased with increasing degree of grafting. Water content was about 1.5 times higher than that of trunk polymer. The maximum ion-exchange capacity was 7.3 meq/g which was 2$\sim$3 times higher than a commercial ion exchange fiber. The average pore size was decreased and BET surface area was increased in order of PPmb, PPmb- g- AAc and APPmb- g- AAc. The average pore size and BET surface area of synthesised fibers were $366.1\;{\AA},\;3.71m^2/g,\;143.3\;{\AA},\;4.94m^2/g,\;40.97\;{\AA},\;8.98m^2/g$, respectively.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.15-24
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• 1992

The effects of CC the ovulatory response, oocyte normality, ovarian steroidogenesis and subsequent embryo developmental potential were examined in PMSG-treated rats. On Days of 25~27 of age, immature female Sprague Dawley rats were treated with three different doses(0.05, 0.1 or 1.0mg /day) of clomiphene citrate or vehicle. The females subsequently received 4IU PMSG on Day 28 and/or 10IU hCG on Day 30, and were killed on Day 31. Some females given 0.1mg CC or vehicle with 4IU PMSG were then mated and killed on Days 2, 3, 4 and 5 of pregnancy. Compared to vehicle(control) group, by increasing the doses of CC, there were a significant decrease in the ovulatory response as judged by both the proportion of rats ovulating and the mean number of oocytes per rat and a marked reduction of ovarian weight. The increasing doses of CC substantially promoted the degeneration(%) of oocytes ovulating in a dose-dependent manner. The CC-mediated inhibitions of the ovulatory response and ovarian weight were oompletely overcome by a subsequent treatment of hCG. Increasing doses of CC resulted in a siginificant elevation of serum estradiol with the decreased levels of progesterone and androgens. The additive treatment with hCG was effective to reduce the elevation of estradiol and to increase the reduction of progesterone produced by high dose(1.0mg) of CC. The preimplantation embryos recovered from 0.1mg CC-treated pregnant rats demonstrated a progressive early loss from Day 3 of pregnancy with a significant increase in the percentage of degeneration during all periods examined, compared to controls. The rate of progressive embryo cleavage in the CC-treated rats were slower than that in controls from Day 3 of pregnancy. Additionally, the percentage of the cleaved embryos recovered from the CC-treated rats remained significantly lower consistently from Day 2 of pregnancy, compared to control regimen. These results demonstrate a possible mechanism of CC-mediated inhibition of ovulatory response in the rats which may include the attenuation or blockade of the endogenous secretion of gonadotropins and also suggest that its detrimental effects observed on oocyte normality and embryonic development may be caused by abnormal follicular steroidogenesis( especially elevated estradiol) preceding fertilization.

• The Korean Journal of Physiology
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• v.21 no.2
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• pp.241-257
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• 1987

The effects of external $Ca^{2+}$ and $Ca^{2+}-antagonists$ on the spontaneous contractions and electrical activities were investigated in guinea-pig stomach in order to clarify the mechanism for the generation of slow waves. Electrical responses of circular smooth muscle cells were recorded using glass capillary microelectrodes filled with 3 M KCl. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% $O_2$ and kept at $35^{\circ}C$. The results obtained were as follows: 1) The amplitude of spontaneous contractions was maximal at around 2-4 mM $Ca^{2+}$, whereas their frequency was inversely related with external $Ca^{2+}$ within the range of 0.5 to 16 mM $Ca^{2+}$. 2) Verapamil suppressed the amplitude of spontaneous contraction in a dose-dependent manner, while the frequency of spontaneous contractions was almost not changed over the whole concentration of verapamil $(0.01{\sim}5\;mg/l)$. 3) Manganese increased both the amplitude and the frequency of spontaneous contractions dose-dependently in low $Mn^{2+}$ (below 0.05 mM $Mn^{2+}$), while their amplitude and frequency were decreased in high $Mn^{2+}$ (above 0.1 mM $Mn^{2+}$). 4) The ampltude and maximum rate of rise of slow waves were incrased in high $Ca^{2+}$ solution. In $Ca^{2+}-free$ solution, the spontaneous contractions recorded simultaneously with slow waves ceased and tonic contraction ($Ca^{2+}-free$ contracture) was developed in parallel with membrane depolarization and the disappearance of slow waves. 5) Verapamil (1 mg/1) decreased the amplitude and maximum rate of rise of slow waves and it depolarized the membrane by about 6 mV, whereas the frequency of slow waves was not affected by verapamil. 6) Manganese showed different characteristic effects between low and high $Mn^{2+}$ on the slow waves: In low $Mn^{2+}$ (0.05 mM $Mn^{2+}$), the initial rapid increases and the subsequent gradual decreases in three parameters of slow waves (amplitude, rate of rise, and frequency of slow waves) till a new steady state were observed. However, in high $Mn^{2+}$ (0.5 mM $Mn^{2+}$) slow waves disappeared and membrane was depolarized. From the above results, the following conclusions could be made: 1) $Ca^{2+}$ is necessary for a generation of the slow waves, even though it is small amount. 2) Verapamil suppresses the spontaneous contractions of gastric antral strip by the decreases in amplitude and maximum rate of rise of slow waves, while this drug does not block the $Ca^{2+}-channel$ involved in the generation of slow waves. 3) Manganese has dual actions on the $Ca^{2+}-channels$; the $Ca^{2+}-channel$ involved in the generation of slow waves (or Na-Ca exchange system) or the channel for the generation of spike potentials are stimulated by a low concentration of $Mn^{2+}$, while both the $Ca^{2+}$. Channels are blocked by high concentration of $Mn^{2+}$.

• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.214-227
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• 2013

Computed tomographic scan as a screening procedures in asymptomatic individuals has seen a steady increase with the introduction of multiple-raw detector CT scanners. This report provides a brief review of the current controversy surrounding CT cancer screening, with a focus on the radiation induced cancer risks and clinical efficacy. 1. A large study of patients at high risk of lung cancer(the National Lung Screening Trial[NLST]) showed that CT screening reduced cancer deaths by 20%(1.33% in those screened compared with 1.67% in those not screened). The rate of positive screening tests was 24.2% and 96.4% of the positive screening results in the low-dose CT group were false-positive. Radiation induced lung cancer risk was estimated the most important in screening population because ERR of radiation induced lung cancer does not show the decrease with increasing age and synergistic connection between smoking and radiation risk. Therefore, the radiation risk may be on the same order of magnitude as the benefit observed in the NLST. Optimal screening strategy remain uncertain, CT lung cancer screening is not yet ready for implementation. 2. Computed tomographic colonography is as good as colonoscopy for detecting colon cancer and is almost as good as colonoscopy for detecting advanced adenomas, but significantly less sensitive and specific for smaller lesions and disadvantageous for subsequent therapeutic optical colonoscopy if polyps are detected. The average effective dose from CT colonography was estimated 8-10 $mS{\nu}$, which could be a significant dose if administered routinely within the population over many years. CT colonography should a) achieve at least 90% sensitivity and specificity in the size category from 6 and 10 mm, b) offer non-cathartic bowl preparation and c) be optimized and standardized CT parameters if it is to be used for mass screening. 3. There is little evidence that demonstrates, for whole-body scanning, the benefit outweighs the detriment. This test found large portion of patient(86~90.8%) had at least one abnormal finding, whereas only 2% were estimated to have clinically significant disease. Annual scans from ages 45 to 75 years would accrue an estimated lifetime cancer mortality risk of 1.9%. There is no group within the medical community that recommends whole-body CT. No good studies indicate the accuracy of screening CT, at this time. The benefit/risk balance for any of the commonly suggested CT screening techniques has yet to be established. These areas need further research. Therefore wild screening should be avoided.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.27-35
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• 2005

This study was performed to determine the effect of three different concentrations of soy-isoflavones on excretions through urine and feces in either sham-operated or ovariectomized female rats. Seventy-two 16-week old Sprague-Dawley rats underwent sham operation or bilateral ovariectomy. They were provided diets containing different levels of soy isoflavones for 6 weeks: 50 ppm (low isoflavone intake; LI), 250 ppm (medium isoflavone intake; MI) and 500 ppm (high isoflavone intake; HI). The subsequent fecal and urinary excretions of daidzein and genistein were then measured. In the sham operated rats, body weight gains and food efficiency ratio of the MI and HI groups were significantly lower than control group, while food intake was not different. However, there was no significant difference in ovariectomized rats. The fecal excretion of daidzein was significantly higher in the HI group than the LI and MI groups, and that of genistein increased as dietary isoflavone intakes increased in both the sham operation and ovariectomy. The reverse tendency of fecal recovery was shown with dietary isoflavone dose only in genistein among ovariectomized rats. When dietary isoflavones were increased from 50 ppm to 500 ppm, the amounts of daidzein and genistein in the urine increased dose-dependently. The higher intakes of isoflavones leaded to lower recovery rates of daidzein and genistein in the urine in the sham-operated rats but not in the ovariectomized rats. The urinary recovery was significantly higher in the LI group than the MI and HI groups in the sham-operated rats. The excreted amounts and recovery of the two isoflavones in the urine were higher in the sham operated groups than in the ovariectomized groups, which implied an increased bioavailability of isoflavones by ovariectomy. Therefore, the results suggest that a more efficient use of soy isoflavones in ovariectomized conditions may occur, which indicates that a higher dose of soy isoflavones is necessary for the postmenopausal states.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.201-205
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• 2007

Purpose: This retrospective study was conducted to assess outcome and to determine the prognostic factors in patients with a desmoid tumor treated with postoperative radiotherapy. Materials and Methods: Twenty-seven patients with a desmoid tumor who were treated with postoperative radiotherapy between June 1984 and October 2005 were analyzed. There were 13 male and 14 female patients. The age of the patients ranged from 3 to 79 years (median age, 28 years). Tumors were located in an extra-abdominal area (21 cases), and in the abdominal walls (6 cases). The tumor size ranged from 2.5 to 25 cm (median size, 7.5 cm) in the largest linear dimension. Thirteen cases received radiotherapy after initial surgery, and 14 recurrent cases received radiotherapy after additional surgery. The total radiation dose given was $45{\sim}66$ Gy (median dose, 59.4 Gy), and the fraction size was $1.8{\sim}2.0$ Gy. Results: The median follow-up period was 61 months (range, $12{\sim}203$ months). Two patients developed local progression and six patients experienced local recurrence. The 5-year disease-free survival rate and the 5-year progression-free survival rate were 61 % and 70%, respectively. Wide local excision was associated with better disease free survival with statistical significance (p=0.028). Radiotherapy after initial surgery (p=0.046) and a higher radiation dose of more than 60 Gy (p=0.049) were associated with better progression free survival with statistical significance. At the time of the last follow-up, the number of additional surgeries was higher in patients that received radiotherapy after reoperation (p<0.001). Conclusion: Radiotherapy after the initial operation improved local control and decreased the number of subsequent operations. Thus, postoperative radiotherapy after an initial operation is recommended in patients with a high risk of recurrence for a desmoid tumor.

• Korean Journal of Oriental Medicine
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• v.5 no.1
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• pp.111-117
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• 1999

Free radicals are thought to be the most important cause of the reperfusion injury subsequent to ischemia. The antioxidant status of the tissue affected by ischemia-reperfusion is of great importance for the primary endogenous defense against the free radical induced injury. Therefore, antioxidant therapy has been shown to be beneficial in neurological disorders such as Alzheimer's disease and cerebral ischemia. In this study, the protective effects of Chungpesagan-tang (CST) was investigated against ischemia/reperfusion-induced cytotoxicity in SK-N-MC neuronal cells It was found out that low concentration of CST was highly effective in protecting neuronal cells against ischemia/reperfusion-induced cytotoxicity. The inhibitory effect of CST on malondialdehyde formation during ischemia/reperfusion-induced oxidative stress in SK-N-MC cells showed obvious dose-dependent responses. Also, CST showed relatively high inhibitory activity to xanthine oxidase induced by ischemia/reperfusion environment Therefore, it is thought that CST has both antioxidant and xanthine oxidase inhibitory effect and can be used for clinical applications for protection of neuronal cells from ischemia-reperfusion injury.

• Journal of Korean Neurosurgical Society
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• v.30 no.3
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• pp.334-341
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• 2001

Objective : We have currently changed treatment strategies to methotrexate(MTX)-based preirradiation chemotherapy with subsequent planned radiation for the initial therapy of primary central nervous system lymphoma (PCNSL). The aim of this study was to evaluate the results of treating PCNSL with chemotherapy plus radiotherapy (CRT) or radiotherapy(RT) alone. Method and Material : This study involved 10 females and 3 males patients with a mean age of 54.2 years. All patients underwent surgery, open(8 cases) or stereotactic biopsy(5 cases) for histological diagnosis. Eleven tumors were diffuse large B-cell lymphomas. Tumor volume change in the follow-up images and survival time were evaluated in patients treated with CRT and RT alone. In the beginning, two patients received ProMACE-Cytabom chemotherapeutic regimen, but did not complete the course and died of progressive tumor 8 and 9 months after diagnosis, respectively. One patient died at 6 months before chemotherapy. These three were excluded from the survival analysis. Five patients(RT group) completed full courses of cranial irradiation with or without boost. For the current combined modality treatment, high-dose MTXbased chemotherapy(systemic and intrathecal MTX, IV vincristine, and oral procarbazine) followed by whole brain irrdiation to 45Gy to tumor was introduced in 5 patients of CRT group. Result : A complete response was achieved in three of five who received RT only and in all of five who received CRT. All patients in CRT groups are in disease free status at a mean 23 months following therapy. The RT group patients refused any additional salvage therapy at tumor relapse and survived at mean 20 months from diagnosis. The Karnofsky performance status improved in eight of ten patients with treatment. The treatment toxicity included leukoencephalopathy in RT group and severe leukopenia, transient hepatitis, avascular necrosis of femoral head, hearing loss, and amenorrhea in CRT group, respectively. Conclusion : The combined modality therapy of MTX-based chemotherapy plus radiotherapy for PCNSL may enhance tumor response and improve patient survival. The patients who received CRT should be carefully followed up because of the higher risk of treatment-induced late neurotoxicity.

• Journal of Korean Neurosurgical Society
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• v.54 no.4
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• pp.329-335
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• 2013

Objective : Brain metastases in primary breast cancer patients are considerable sources of morbidity and mortality. Gamma knife radiosurgery (GKRS) has gained popularity as an up-front therapy in treating such metastases over traditional radiation therapy due to better neurocognitive function preservation. The aim of this study was to clarify the prognostic factors for local tumor control and survival in radiosurgery for brain metastases from primary breast cancer. Methods : From March 2001 to May 2011, 124 women with metastatic brain lesions originating from a primary breast cancer underwent GKRS at a tertiary medical center in Seoul, Korea. All patients had radiosurgery as a primary treatment or salvage therapy. We retrospectively reviewed their clinical outcomes and radiological responses. The end point of this study was the date of patient's death or the last follow-up examination. Results : In total, 106 patients (268 lesions) were available for follow-up imaging. The median follow-up time was 7.5 months. The mean treated tumor volume at the time of GKRS was 6273 $mm^3$ (range, 4.5-27745 mm3) and the median dose delivered to the tumor margin was 22 Gy (range, 20-25 Gy). Local recurrence was assessed in 86 patients (216 lesions) and found to have occurred in 36 patients (83 lesions, 38.6%) with a median time of 6 months (range, 4-16 months). A treated tumor volume >5000 $mm^3$ was significantly correlated with poor local tumor control through a multivariate analysis (hazard risk=7.091, p=0.01). Overall survival was 79.9%, 48.3%, and 15.3% at 6, 12, and 24 months, respectively. The median overall survival was 11 months after GKRS (range, 6 days-113 months). Multivariate analysis showed that the pre-GKRS Karnofsky performance status, leptomeningeal seeding prior to initial GKRS, and multiple metastatic lesions were significant prognostic factors for reduced overall survival (hazard risk=1.94, p=0.001, hazard risk=7.13, p<0.001, and hazard risk=1.46, p=0.046, respectively). Conclusion : GKRS has shown to be an effective and safe treatment modality for treating brain metastases of primary breast cancer. Most metastatic brain lesions initially respond to GKRS, though, many patients have further CNS progression in subsequent periods. Patients with poor Karnofsky performance status and multiple metastatic lesions are at risk of CNS progression and poor survival, and a more frequent and strict surveillance protocol is suggested in such high-risk groups.

• The Korean Journal of Pain
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• v.9 no.1
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• pp.151-158
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• 1996

Background: Buprenorphine, a new synthetic thebaine derivative, is a partial agonist of the opioid $\mu$-receptor with high receptor affinity, great lipid solubility, and slow rate of opiate receptor association and dissociation. Continuous epidural infusion of opioid can possibly produced undesirable effects, such as respiratory depression, pruritus, etc, in spite of effective postoperative analgesia. Methods: The present study was undertaken to compare the analgesic properties and side effects of continuous epidural infusion of buprenorphine combined with bupivacaine, and morphine combined with bupivacaine in 90 patients following elective gynecologic lower abdominal surgery. At the end of surgery, the initial bolus doses were 3 mg morphine (M group), 0.15 mg buprenorphine (0.15B group), 0.3 mg buprenorphine (0.3B group) combined with 0.25% bupivacaine 10ml, and subsequent continuous infusion doses were 6 mg morphine plus 0.125% bupivacine 100 ml (M group) and 0.6mg buprenorphine plus 0.125% bupivacaine 100 ml (0.15B, 0.3B, group) during 48 hours. The assessment of analgesic efficacy and side effects were made at arrival of recovery room, 1 hr, 4 hr, 8 hr, 24 hr, 36 hr, and 48 hr after the epidural injection. Results: The pain score during 48 hours was significantly higher in the 0.15B group than in the M group and 0.3B group (P<0.05), and the number of patients requiring additional analgesics was significantly higher in the 0.15B group than in the M group and 0.3B group (P<0.05). Signs of respiratory depression were not noted, and the incidence of pruritus, nausea, and vomiting was slightly lower in the 0.15B group and 0.3B group than in the M group, and the incidence of sedation and urinary retention was similar in three group. The subjective rating of satisfaction was better in the 0.3B group than in the M group and 0.15B group (P<0.05). Conclusion: The above results suggest that continuous epidural infusion of buprenorphine combined with low-dose bupivacaine is an advisable method of postoperative analgesia.