• Korean Journal of Environmental Agriculture
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• v.40 no.1
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• pp.40-48
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• 2021

BACKGROUND: Although the calcined oyster shell can be used as a calcium-rich adsorbent for phosphate removal, information about it is limited. The purpose of this study was to evaluate the phosphate adsorption characteristics and its mechanism using calcined oyster shells. METHODS AND RESULTS: In this study, calcined oyster shell (C-OS600) was prepared by calcining oyster shells (P-OS) at 600℃ for 20 min. Phosphate adsorption by C-OS600 was performed under various environmental conditions. Phosphate adsorption by C-OS600 occurred rapidly at the beginning of the reaction, and the time to reach equilibrium was less than 1 h. The optimal isotherm and kinetic models for predicting the adsorption of phosphate by C-OS600 were the Langmuir isotherm and pseudo-second order kinetic model, respectively, and the maximum adsorption capacity derived from the Langmuir isotherm was 68.0 mg/g. The adsorption properties of phosphate by C-OS600 were dominantly influenced by the initial pH and C-OS600 dose. In addition, SEM-EDS and FTIR analysis clearly showed a difference in C-OS600 before and after phosphate adsorption, which proved that phosphate was adsorbed on the surface of C-OS600. CONCLUSION: Overall, the calcined oyster shell can be considered as an useful and effective adsorbent to treat wastewater containing phosphate.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.3
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• pp.245-253
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• 2011

Purpose: The aim of this in vitro study was to estimate surface characteristic after peptide coating and investigate biological response of human mesenchymal stem cell to anodized titanium discs coated with RGD peptide by physical adhesion and chemical fixation. Materials and methods: Fluorescence isothiocyanate (FITC) modified RGD-peptide was coated on the anodized titanium discs (diameter 12 mm, height 3 mm) using two methods. One was physical adhesion method and the other was chemical fixation method. Physical adhesion was performed by dip and dry procedure, chemical fixation was performed by covalent bond via silanization. In this study, human mesenchymal stem cell was used for experiments. The experiments consisted of surface characteristic evaluation after peptide coating, analysis about cell adhesion, proliferation, differentiation, and mineralization. Obtained data are statistically treated using Kruskal-Wallis test and Bonferroni test was performed as post hoc test (P=.05). Results: The evaluation of FE-SEM images revealed no diffenrence at micro-surfaces between each groups. Total coating dose was higher at physical adhesion experimental group than at chemical fixation experimental group. In cell adhesion and proliferation, RGD peptide coating did not show a statistical significance compared with control group (P>.05). In cell differentiation and mineralization, physical adhesion method displayed significantly increased levels compared with control group and chemical fixation method (P<.05). Conclusion: RGD peptide coating seems to enhance osseointegration by effects on the response of human mesenchymal stem cell. Especially physical adhesion method showed more effective than chemical fixation method on response of human mesenchymal stem cell.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.87-94
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• 2001

Purpose : To evaluate the role of LINAC-based stereotactic radiosurgery (SRS) in the management of meningiomas, we reviewed clinical response, image response, neurological deficits for patients treated at our institution. Methods and materials : Between February 1995 and December 1999, twenty-six patients were treated with SRS. Seven patients had undergone prior resection. Nineteen patients received SRS as the initial treatment. There were 7 male and 19 female patients. The median age was 51 years (range, $14\~67\;years$). At least one clinical symptom presented at the time of SRS in 17 patients and cranial neuropathy was seen in 7 patients. The median tumor volume was $4.7\;cm^3\;(range,\;0.7\~16.5\;m^3)$. The mean marginal dose was 15 Gy (range, $10\~20\;Gy$), delivered to the $80\%$ isodose surface (range, $46\~90\%$). The median clinical and imaging follow-up periods were 27 months (range, 1-71 months) and 25 months (range, $1\~52\;months$), respectively. Results : Of 14 patients who had clinical follow-up of one year or longer, thirteen patients $(93\%)$ were improved clinically at follow-up examination. Clinical symptom worsened in one patient at 4 months after SRS as a result of intratumoral edema, who underwent surgical resection at 7 months. OF 14 patients who had radiologic follow-up of one year or longer, tumor volume decreased in 7 patients $(50\%)$ at a median of 11 months (range, $6\~25\;months$), remained stable in 6 patients $(43\%)$, and increased in one patient $(7\%)$, who underwent surgical resection at 44 months. New radiation-induced neurological deficits developed in six patients $(23\%)$. Five patients $(19\%)$ had transient neurological deficits, completely resolved by conservative treatment including steroid therapy. Radiation-induced brain necrosis developed in one patient $(3.8\%)$ at 9 months after SRS who followed by surgical resection of tumor and necrotic tissue. Conclusions : LINAC-based SRS proves to be an effective and safe management strategy for small to moderate sized meningiomas, inoperable, residual, and recurrent, but long-term follow-up will be necessary to fully evaluate its efficacy. To reduce the radiation-induced neurological deficit for large size meningioma and/or in the proximity of critical and neural structure, more delicate treatment planning and optimal decision of radiation dose will be necessary.

• Tuberculosis and Respiratory Diseases
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• v.40 no.3
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• pp.236-249
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• 1993

Background: Among the injurious agents to which the lung airspaces are constantly exposed are reactive species of oxygen. It has been widely believed that reactive oxygen species may be implicated in the etiology of lung injuries. In order to elucidated how this oxidant causes lung cell injury, we investigated the effects of exogenous $H_2O_2$ on alveolar epithelial barrier characteristics. Methods: Rat type II alveolar epithelial cells were plated onto tissue culture-treated polycarbonate membrane filters. The resulting confluent monolayers on days 3 and 4 were mounted in a modified Ussing chamber and bathed on both sides with HEPES-buffered Ringer solution. The changes in short-circuit current (Isc) and monolayer resistance (R) in response to the exogenous hydroperoxide were measured. To determine the degree of cellular catalase participation in protection against $H_2O_2$ injury to the barrier, experiments were repeated in the presence of 20 mM aminotriazole (ATAZ, an inhibitor of catalase) in the same bathing fluid as the hydroperoxide. Results: These monolayers have a high transepithelial resistance (>2000 ohm-$cm^2$) and actively transport $Na^+$ from apical fluid. $H_2O_2$(0-100 mM) was then delivered to either apical or basolateral fluid. Resulting indicated that $H_2O_2$ decreased Isc and R gradually in dose-dependent manner. The effective concentration of apical $H_2O_2$ at which Isc (or R) was decreased by 50% at one hour ($ED_{50}$) was about 4 mM. However, basolateral $H_2O_2$ exposure led to $ED_{50}$ for Isc (and R) of about 0.04 mM. Inhibition of cellular catalase yielded $ED_{50}$ for Isc (and R) of about 0.4 mM when $H_2O_2$ was given apically, while $ED_{50}$ for basolateral exposure to $H_2O_2$ did not change in the presence of ATAZ. The rate of $H_2O_2$ consumption in apical and basolateral bathing fluids was the same, while cellualr catalase activity rose gradually with time in culture. Conclusion: Our data suggest that basolateral $H_2O_2$ may affect directly membrane component (e.g., $Na^+,\;K^+$-ATPase) located on the basolateral cell surface. Apical $H_2O_2$, on the other hand, may be largely degraded by catalase as it passes through the cells before reaching these membrane components. We conclude that alveolar epithelial barrier integrity as measured by Isc and R are compromised by $H_2O_2$ being relatively sensitive to basolateral (and insensitive to apical) $H_2O_2$.

• Journal of Veterinary Clinics
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• v.23 no.3
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• pp.230-235
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• 2006

This study was performed in rats to find the minimum dose of melatonin that can effectively prevent the formation of postoperative intraperitoneal adhesions. Forty-two Sprague Dawley male rats were divided into six groups consisting of 7 rats, respectively. After celiotomy, five abrasions of $0.5{\times}1cm$ area were made on the antimesenteric serosal surface of the colon with a scalpel blade. The abdominal cavity was filled with 1 ml of solution containing 1 mg/kg(Mel 1), 3 mg/kg(Mel 3), 10 mg/kg(Mel 10), 30 mg/kg(Mel 30) and 5% ethanol solution(sham) through the catheter, using a sterile syringe before abdominal closure. Control group was given no adjuvant. The locations and values of adhesion were assessed through the second operation on the 14th day after the first operation. The adhesions were located on serosa to mesentery(54 of 210, 25.7%), serosa to serosa(44 of 210, 21%), serosa to omentum (12 of 210, 5.7%) and serosa to parietal peritoneum(0 of 210, 0%). The incidences of adhesion in Control, Sham, Mel 1, Mel 3, Mel 10 and Mel 30 were 68.6%, 91.4%, 57.1%, 60.1%, 17.1% and 20%, respectively. The values of adhesion separation in Mel 10 and Mel 30 group were lower than those in other groups. However, there was no significant(p<0.05) between Mel 10 and Mel 30 group. This study showed that 10 mg/kg of melatonin were effective in reducing the intraperitoneal adhesion.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.1-7
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• 2002

To study the increased resistance in fish against Vibrio vulnificus known as an important agent of vibrio septicemia in human, we analyzed specific and nonspecific immune response in flounder after administration of V. vulnificus bacterins by oral route. It contained the comparison of antibody concentrations in the sera of flounder after oral administration by two different protocols with uncoated heat killed bacterin of V vulnificus (UHKB, 20 mg/kg body weight), i.e., 4 weeks continuously (group 4W) and taking 2 weeks resting period between the 1st and last week of administration (group 1-2-1W). Even though, 1-2-1W group showed significantly increased level of specific antibody in serum, it did not reach to that of 4W group. Certainly, flounder vaccinated twice a week for four weeks (20 mg/kg b.w.) showed increased concentration of specific antibody against V. vulnificus at week 2 after last administration by oral route and maintained throughout the experimental period. It also was confirmed by the increased numbers of specific antibody secreting cells (SASC) in the leukocytes isolated from the splenocytes of the flounder of 4W group at week 1 after last administration until the end of experimental period. However, enteric, acid-resistant film coated heat killed bacterin (ECHB) did not show both greater immune reaction for antibody production and faster elimination of a challenge dose of V. vulnificus compared with those of the UHKB. These results suggested that UHKB administered by oral route was very effective method to prevent the contamination of V vulnificus in flounder, and did not show the increased antigenicity by coating the surface with acid-resistant film.

• Radiation Oncology Journal
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• v.21 no.2
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• pp.107-111
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• 2003

Purpose: To establish the role of stereoactic radiosurgery using a linear accelerator for the treatment of patients with cavernous angloma. Materials and Methods: Between February 1995 and May 1997, 11 patients with cavernous angioma were treated with stereotactic radiosurgery using a linear accelerator. Diagnoses were based on the magnetic resonance imaging in 8 patients, and the histological in 3. The vascular lesions were located on the brainstem (5 cases), cerebellum (2 cases) thalamus (1 case) and cerebrum (3 cases). The clinical presentation at onset included previous intracerebral hemorrhages (9 cases) and seizures (2 cases). All patients were treated with a a linac-based radiosurgery. The median dose of radiation delivered was 16 Gy ranging from 14 to 24 Gy, which was typically proscribed to the 80$\%$ isodose surface (range 50 $\~$ 80$\%$), corresponding to the periphery of the lesion with a single isocenter. Ten patients were followed-up. Results: The median follow-up was 49 months ranging from 8 to 73 months, during which time two patients developed an intracerebral hemorrhage, 1 at 8 months, with the other at 64 months post radiosurgery. One patient developed neurological deficit after radiosurgery, and two developed an edema on the T2 weighted images of the MRI surrounding the radiosurgical target. Conclusion: The use of stereotactic radiosurgery in the treatment of a cavernous angioma may be effective in the prevention of rebleedlng, and can be safely delivered. However, a longer follow-up period will be required.

• Journal of Food Hygiene and Safety
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• v.33 no.2
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• pp.140-145
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• 2018

The skin of the human body occupies the largest surface area of the body and acts as a protection for the person's internal organs. As such, the skin is a major target of oxidative stressors, and these oxidative stressors are known to contribute to skin aging over the course of time. For the most part, an antioxidant is an effective approach to utilize to prevent symptoms related to the reactive oxygen species (ROS)-induced aging of the skin. Therefore, we investigated the antioxidant and anti-aging activity of the leaves of the Quercusaliena Blume extract (QBE). In our study, we confirmed that the cell viability tested with XTT {2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide innersalt} assay was not affected up to a concentration of $100{\mu}g/mL$. In addition, the cell viability of HDF cells induced by hydrogen peroxide was recovered from 81% to 104% after treatment with QBE, which showed the greater protective effect than that of ascorbic acid. Treatments of QBE dose-dependently inhibited reactive oxygen species (ROS) production in HDF cells induced by hydrogen peroxide, which correlated with their protective effects on cell viability. Since QBE treatment exhibited the suppression effect of skin aging by decreasing the ROS production, QBE could be used as a not only natural anti-aging but also antioxidant resource.

• Resources Recycling
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• v.31 no.4
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• pp.56-65
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• 2022

Copper is one of the non-ferrous metals used in the electrical/electronic manufacturing industries due to its superior properties particularly the high conductivity and less resistivity. The effluent generated from the surface finishing process of these industries contains higher copper content which gets discharged in to water bodies directly or indirectly. This causes severe environmental pollution and also results in loss of an important valuable metal. To overcome this issue, continuous R & D activities are going on across the globe in adsorption area with the purpose of finding an efficient, low cost and ecofriendly adsorbent. In view of the above, present investigation was made to compare the performance of a plant root (Datura root powder) as a bio-adsorbent to that of the synthetic one (Tulsion T-42) for copper adsorption from such effluent. Experiments were carried out in batch studies to optimize parameters such as adsorbent dose, contact time, pH, feed concentration, etc. Results of the batch experiments indicate that 0.2 g of Datura root powder and 0.1 g of Tulsion T-42 showed 95% copper adsorption from an initial feed/solution of 100 ppm Cu at pH 4 in contact time of 15 and 30 min, respectively. Adsorption data for both the adsorbents were fitted well to the Freundlich isotherm. Experimental results were also validated with the kinetic model, which showed that the adsorption of copper followed pseudo-second order rate expression for the both adsorbents. Overall result demonstrates that the bio-adsorbent tested has a potential applicability for metal recovery from the waste solutions/effluents of metal finishing units. In view of the requirements of commercial viability and minimal environmental damage there from, Datura root powder being an effective material for metal uptake, may prove to be a feasible adsorbent for copper recovery after the necessary scale-up studies.