• YAKHAK HOEJI
• /
• v.40 no.4
• /
• pp.400-410
• /
• 1996

In oder to develop the controlled release of drugs from the suppositories, in vitro drug release and in vivo absorption in rabbits were investigated. Various suppo sitory forms with hollow cavities, into which drugs in the form of fine powder or solid dispersion system(SDS) could be placed, were utilized. The oleaginous Witepsol H-15 (WH-15) as a base, and indomethacin (IDM) of a very slightly soluble drug and propranolol-HCL (PPH) of a very soluble drug were employed as model drugs. The in vitro drug release showed that the cumulative release amount of PPH from PPH-(methylcellulose) MC-SDS and PPH-(ethylcellulose) EC-SDS hollow type suppositories reached 40% and 12% in 6 hrs,respectively. On the other hand, the drug release for a conventional suppository was 80% in 6 hrs. For the IDM suppositories,the cumulative drug release from IDM-(polyvinylpyrrolidone) PVP-SDS hollow type suppositories reached 99% in 24 hrs, whereas that from a conventional suppository reached 85%. An in vivo experiment with rabbits showed that IDM-PVP-SDS hollow type suppository delayed the absorption of IDM, significantly. The $t_{max},\;C_{max}\;and\;AUC_{0{\to}8}$ of IDM-PVP-SDS suppository were 60 min, 12.12${\mu}g$/ml and 2657${\mu}g$/ml/min, respectively. The $t_{max},\;C_{max}\;and\;AUC_{0{\to}8}$ of controlled group were 20 min, 15.49${\mu}g$/ml and 2190${\mu}g$/ml/min, respectively.

• Polymer(Korea)
• /
• v.25 no.6
• /
• pp.884-892
• /
• 2001

Biodegradable wafers were prepared with poly (L-lactide-co-glycolide) (50 : 50 mole ratio of lactide to glycolide, molecular weight:5000 g/mole) by direct compression method for the sustained release of nifedipine to investigate the possibility of the treatment of hypertension. PLGA wafers were prepared by altering initial drug/polymer loading ratio, wafer thickness, and hydroxypropyl methylcellulose (HPMC) content. These wafers showed new zero-order release patterns for 11 days, and various biphasic release patterns could be obtained by altering the composition of wafers such as addition of matrix binder as HPMC to the PLGA wafer to reduce release rate of initial phase. The onset of polymer mass loss only occured after 4 days and about 40% of mass loss was observed after 11 days nifedipine release. This system had advantages in terms of simplicity in design and obviousness of drug release rate and may be useful as an implantable dosage form.

• YAKHAK HOEJI
• /
• v.58 no.2
• /
• pp.81-90
• /
• 2014

In order to determine the functional benefits of Cordyceps militaris in the immune system, we examined the immunomodulatory activities of C. militaris using an immunocompromised C57BL/6 mice, mouse spleen cells, RAW 264.7 macrophage cells, and A549 lung carcinoma cells. Mice were injected intraperitioneally with an immunosuppressive drug, cyclophosphamide, and then administered orally with 30, 100 and 300 mg/kg of 50% ethanol extract of C. militaris (CME 30, CME 100 and CME 300) for 14 days. CME increased splenocyte proliferation and natural killer (NK) cell activity compared to 3% hydroxypropyl methylcellulose-treated control mice. CME also increased the production of Th1 cytokines, IL-2 and TNF-${\alpha}$ in spleen cells isolated from CME-injected mice and in vitro, which suggested the enhanced cellular immunity in response to CME. CME also increased splenocyte proliferation, NK cell activity, and IL-2 and TNF-${\alpha}$ production compared to 1 ${\mu}M$ methotrexate-treated spleen cells in vitro. We examined whether C. militaris regulates the production of inflammatory mediators in LPS-stimulated RAW 264.7 cells. CME inhibited LPS-induced NO production and iNOS expression in a dose dependent manner, while COX-2 expression was remained unchanged. In addition, CME also has free radical scavenging activity, indicating its antioxidant activity. These results indicate that C. militaris enhances immune activity by promoting immune cell proliferation and cytokine production.

• Journal of Pharmaceutical Investigation
• /
• v.26 no.4
• /
• pp.299-308
• /
• 1996

In order to develop the controlled release of a drug from the suppsitories, in vitro drug release and in vivo absorption in rabbits were investigated. Various suppository forms with hollow cavities, into which drugs in the form of fine powder or solid dispersion system(SDS) could be placed, were utilized. The polyvinyl alcohol(PVA) hydrogel as a base, and propranolol HCl(PPH) as a model drug were employed. In vitro drug dissolution studies showed that the dissolved amounts(%) of PPH from PPH-methylcellulose(MC)-SDS and PPH-ethylcellulose(EC)-SDS reached 100% and 63% in 4.5-hours, respectively. In the relative strength test for PVA hydrogel, PVA hydrogel became harder and more rigid when the number of freezing-thawing cycles and the ratio of PVA 2000 were increased. In vitro drug release profile revealed that the release rate(%) of PPH from PPH-EC-SDS and PPH-MC-SDS hollow type suppositories were sustained. The release amount(%) of PPH from PPH-EC-SDS hollow type suppositories was not affected by storage time, but since the use of hydrophilic MC made PPH diffuse into the hydrogel after it absorbed the water of base, the various release patterns were appeared as the storage time went by. In vivo absorption experiments with rabbits showed that PPH-EC-SDS(PPH : EC=1:3) hollow type suppository delayed the absorption of PPH, significantly. The $C_{max}$, $AUC_{0{\rightarrow}8}$ and MRT of PPH powder hollow type suppository were $196.37{\pm}5.63\;ng/ml$, 1105.26 ng/ml/min and 8.66 min, respectively. The $C_{max}$, $AUC_{0{\rightarrow}8}$ and MRT of PPH-EC-SDS(PPH : EC=1:3) were $91.30{\pm]14.14\;ng/ml$, 554.69 ng/ml/min, 235.99 min, respectively.

• Restorative Dentistry and Endodontics
• /
• v.40 no.2
• /
• pp.104-112
• /
• 2015

Objectives: This study was performed to investigate the effects of different intracanal medicaments on chemical structure and microhardness of dentin. Materials and Methods: Fifty human dentin discs were obtained from intact third molars and randomly assigned into two control groups and three treatment groups. The first control group received no treatment. The second control group (no medicament group) was irrigated with sodium hypochlorite (NaOCl), stored in humid environment for four weeks and then irrigated with ethylenediaminetetraacetic acid (EDTA). The three treatment groups were irrigated with NaOCl, treated for four weeks with either 1 g/mL triple antibiotic paste (TAP), 1 mg/mL methylcellulose-based triple antibiotic paste (DTAP), or calcium hydroxide [$Ca(OH)_2$] and finally irrigated with EDTA. After treatment, one half of each dentin disc was subjected to Vickers microhardness (n = 10 per group) and the other half was used to evaluate the chemical structure (phosphate/amide I ratio) of treated dentin utilizing attenuated total reflection Fourier transform infrared spectroscopy (n = 5 per group). One-way ANOVA followed by Fisher's least significant difference were used for statistical analyses. Results: Dentin discs treated with different intracanal medicaments and those treated with NaOCl + EDTA showed significant reduction in microhardness (p < 0.0001) and phosphate/amide I ratio (p < 0.05) compared to no treatment control dentin. Furthermore, dentin discs treated with TAP had significantly lower microhardness (p < 0.0001) and phosphate/amide I ratio (p < 0.0001) compared to all other groups. Conclusions: The use of DTAP or $Ca(OH)_2$ medicaments during endodontic regeneration may cause significantly less microhardness reduction and superficial demineralization of dentin compared to the use of TAP.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.45 no.6
• /
• pp.10-16
• /
• 2013

This study aims to carry out the final evaluation on the deterioration stability of dewaxing and strengthening treatments devised to conserve and restore the beeswax-treated volumes of the Annals of the Joseon Dynasty. Thus, this study artificially deteriorated dewaxed Hanji, strengthened Hanji and beeswax-treated Hanji with optimized processing conditions applied, and comparatively analyzed the deterioration characteristics of each kind of Hanji. As a result of this study, it turned out that there was the loss of physical strength and the value of $L^*$ was increased and the values of $a^*$ and $b^*$ were decreased from removing beeswax after dewaxing by supercritical fluid extraction (SFE). Also deteriorated strength during dewaxing was reinforced by strengthening treatment with methylcellulose and it showed higher strength than beeswax-treated Hanji. From the evaluation on deterioration stability after dewaxing and strengthening, it turned out that deterioration stability of strengthened Hanji is the superior. Therefore, it is presumed that conservation of aged beeswax-treated Hanji can be improved and extended when dewaxing and strengthening are applied under optimum conditions.

• Clinical and Experimental Reproductive Medicine
• /
• v.48 no.3
• /
• pp.236-244
• /
• 2021

Objective: Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, irregular menstruation, ovulatory dysfunction, and insulin resistance. Recent studies have reported the possible role of phytoestrogens in PCOS. This animal study aimed to evaluate the effects of genistein on insulin resistance, inflammatory factors, lipid profile, and histopathologic indices on PCOS. Methods: PCOS was induced by 1 mg/kg of letrozole in adult Sprague-Dawley rats. The rats then received normal saline (PCOS group), 150 mg/kg of metformin, or 20 mg/kg of genistein dissolved in 1% methylcellulose solution for 42 days. Body weight, the glycemic and lipid profile, and inflammatory, antioxidative, and histopathological parameters were assessed at the end of the intervention. Results: Treatment with genistein significantly alleviated the increased level of fasting blood insulin (p=0.16) and the homeostatic model assessment of insulin resistance (p=0.012). In addition, the genistein group had significantly lower levels of serum malondialdehyde (p=0.039) and tumor necrosis factor-alpha (p=0.003), and higher superoxide dismutase enzyme activity (p<0.001). Furthermore, the histopathological analysis indicated that genistein administration led to an increase in luteinization and the development of fewer cysts (p<0.05). Conclusion: Biochemical and histopathological analyses indicated that genistein administration to rats with PCOS induced significant remission in oxidative, inflammatory, and glycemic and histopathologic parameters.

• Journal of the Korea Convergence Society
• /
• v.10 no.2
• /
• pp.41-48
• /
• 2019

The effects of HPMC (hydroxypropyl methylcellulose) on instant fried noodles regarding oil uptake and in vitro lipid digestibility were evaluated according to different viscosity levels, as well as the same apparent viscosity. The oil uptake and lipid digestibility decreased with the increasing HPMC viscosity and replacement level, demonstrating that the reduced oil uptake and lipid digestibility may be caused by the high viscosity of HPMC. Furthermore, the oil uptake and lipid digestibility of noodles with HPMC at both apparent viscosities decreased with the increasing viscosity of HPMC in spite of having the same apparent viscosity. As a result, the high viscosity of HPMC on instant fried noodles was more critical factor compared to apparent viscosity for lowering oil uptake and lipid digestibility.

• Journal of Acupuncture Research
• /
• v.39 no.4
• /
• pp.310-316
• /
• 2022

Background: Verbenalin is an iridoid glucoside, which is among the active components of some medicinal herbs such as Verbena officinalis Linn, and Cornus officinalis Siebold and Zucc. Previous studies have confirmed the antioxidant activity and neuroprotective potential of verbenalin. To confirm the safety of verbenalin, an approximate lethal dose was determined based on a single oral dose toxicity study. Methods: Institute of Cancer Research mice were randomly assigned to three verbenalin exposure groups (250, 500, and 1,000 mg/kg) and a control group (5% methylcellulose solution). There were (5 male and 5 female mice per group). Mortality, clinical signs, and body weight were monitored for 14 days, and necropsies were conducted. Results: No mortalities were observed in the control group or the verbenalin 250 mg/kg group, whereas mortalities were observed in the 500 mg/kg and 1,000 mg/kg verbenalin groups. During the observation period, stool abnormalities such as mucous stools were observed. Clinical signs such as loss of locomotor activity were observed in the 500 mg/kg and 1,000 mg/kg verbenalin groups. During the study period, significant changes in body weight were observed in the 500 mg/kg and 1,000 mg/kg verbenalin groups; however, no gross abnormalities were observed at necropsy. Overall, no toxicity was found in the 250 mg/kg group. Conclusion: The approximate lethal dose of verbenalin was estimated to be 500 mg/kg. For a more accurate assessment of the safety of verbenalin, other types of studies such as repeated-dose toxicity studies should also be conducted.

• Clinical and Experimental Pediatrics
• /
• v.45 no.2
• /
• pp.247-255
• /
• 2002

Purpose : This study was undertaken to obtain basic data about the megakaryocyte colony formation of fetal liver cells by using immunocytochemical staining and ex vivo culture with growth factors. Methods : The mononuclear cells were isolated from fetal liver and bone marrow with idiopathic thrombocytopenic purpura(ITP) and pancytopenia. These mononuclear cells were cultured in $MegaCult^{TM}-C$(Stem Cell Tech, Canada) media in the presence of growth factors and CFU-Megakaryocyte( CFU-Mk) colonies were counted on day 12. The expansion of CD34+ and CD41+ cell was analyzed by flow cytometry after 5 days incubation using flask culture. Results : The numbers of CFU-Mk colonies of mononuclear cells obtained from fetal liver in the 11th week gestational age were more than those in the 19th week specimens; growth factors could not enhance the colony expansion in all cases. Total numbers of CFU-Mk colony of fetal liver cells were higher than bone marrow from ITP or pancytopenia groups. The numbers of pure or large CFU-Mk colonies of fetal liver cells were also higher than bone marrow specimens. The rate of CD34+ cell expression of fetal liver was increased after flask culture and the enhancement effect of epression was seen only in cases which added thrombopoietin. The rate of CD41+ cell expression of fetal liver was increased after incubation, but the enhancement effect of growth factors was unclear. Conclusion : This study revealed good results about the megakaryocyte colony assay of fetal liver mononuclear cells using $MegaCult^{TM}-C$ media. This study suggests that the fetal liver could be a good source of megakaryocytic progenitor cells for clinical application in hematopoietic stem cell transplantation.