• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.647-659
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• 2008

Colloids are a heterogeneous system in which particles of a few nanometers to hundreds micrometers in size are finely dispersed in liquid medium, but show homogeneous properties in macroscopic scale. They have attracted much attention not only as model systems of natural atomic and molecular self-assembled structures but also as novel structural materials of practical applications in a wide range of areas. In particular, recent advances in colloidal science have focused on nano-bio materials and devices which are essential for drug discovery and delivery, diagnostics and biomedical applications. In this review, first we introduce nano-bio colloidal systems and surface modification of colloidal particles which creates various functional groups. Then, various methods of fabrication of colloidal particles using holographic lithography, microfluidics and virus templates are discussed in detail. Finally, various applications of colloids in metal inks, three-dimensional photonic crystals and two-dimensional nanopatterns are also reviewed as representative potential applications.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.5
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• pp.54-59
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• 2013

Micro shock tubes are now-a-days used for a variety engineering applications such as in the field of aerospace, combustion technology and drug delivery systems. But the flow characteristics of micro shock tube will be different from that of well established conventional macro shock tube under the influence of very low Reynolds number and high Knudsen number formed due to smaller diameter. In present study, experimental studies were carried out to a closed end (downstream) Micro Shock Tube with two different diameters were investigated to understand the flow characteristics. Pressure values were measured at different locations inside the driver and driven section. The results obtained show that with the increase in diameter the shock propagation velocity increases as well as the effect of reflected shock wave will be more significant under the same diaphragm rupture pressure.

• The Journal of Dong Guk Oriental Medicine
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• v.5
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• pp.231-271
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• 1996

Obstetrics and Gynecology include gynecology which is concerned with the treatment for the disease based on physiology and pathology of women, and obstetrics which is concerned with pregnancy delivery. These obstetics and gynecology can be said to date from the birth of human beings. This paper has carried on the studies about the generating and developing process of obstetics and gynecology. The results of this study are as follows : Distinction in Northern and Southern Dynasties were much more Obstetrics and Gynecology studying the Obstetrics and Gynecology books in that time, the study about "oncosis" (腫瘤) and forms of drug, pill, powder, pIaster were carried on. The highest distinction in Sui age were research and development on pathogenesis and cause of disease about Obstetrics and Gynecology disease and it was appeared representatively in "Zhubingyuanhoulun""諸病源候論" which was special book on cause of disease and pathogenesis and syndrome, And it was explained about abnormal vaginal discharge in this book. Obstetrics and Bynecology were developed on theory and clincis in Tang age when "Taiyshu"(太醫暑) was established. "Taiyshu"(太醫暑) taked complete charge of medical operation and education, published much excellent Obstetrics and Gynecology books than the past. Among them specially "Qianjinyaofang""千金要方" explained Obstetrics and Gynecology matter first in three volumes and "Qianjinyifang""千金翼方" explained this matter first in four volumes. This point indicate that Obstetrics and Gynecology's importance was established in Tang age, so Obstetrics and Gynecology's developmental history, Song age was the acme period. "Taiyju"(太醫局) was established in "xining""熙?" 9 year and Obstetrics belonged to one of nine departments under "Taiyun"(太醫局), so Obstetrics and Gynecology was separated from the other medical parts and it was prepared of it's progressing bases independently and appeared of changes in quality and increase in quantity about theory and prescription of Obstetrics and Gynecology, specially determination of treatment based on the differentiation of symptoms and sighs was taked a serious view. Besides four great physicians in Jing and Yuan dynasies diversified Obstetrics and Gynecology contents through their only medical theory and clinical treatment.

• Polymer(Korea)
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• v.33 no.4
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• pp.353-357
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• 2009

Spray drying is an effective and stable process, which has been widely used to produce pharmaceutical powders. In the traditional spray drying process, it was not quite easy to control the aggregation and the size of particles. Particularly, the preparation of polymeric particles was relatively hard compared to the preparation of food and pharmaceutical ingredients, typically organic materials of small molecular weights. In this study, modification of a conventional spray dryer was tried to use electrical charge and co-axial nozzles to prepare polymeric particles. Poly(ethylene glycol) and poly (D,L-lactide-co-glycolide) were used as the inner polymeric materials, and lactose as the outer shell materials. The results showed that electrohydrodynamic spray-dried particles had a relatively uniform size and particle morphology, and the aggregation of particles could be suppressed compared to the conventional spray-dried particles. The electrohydrodynamic spray-dried powders consisted of spherical particles of $2{\sim}5{\mu}m$ diameters.

• Journal of the Korean Vacuum Society
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• v.19 no.2
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• pp.105-113
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• 2010

One-dimensional nanostructures have been researched widely because of its unique physical properties such as optical, electrical, mechanical, and chemical properties in comparison with bulk structures. Especially nanotubular structures are able to provide larger surface area, capability to load purposeful materials, and unique mechanical modulus. We reviewed the oxide nanotube technology with focusing on the method of template-directed fabrication. We can easily control of physical dimensions of nanotubes by control of nanotemplate and fabrication condition. and template-directed fabrication is ideal tool to fabricate the amount of monodisperse nanotubes. They have potentials for application in solar cell, drug-delivery, Li-ion batteries and photocatalyst. We discussed these potential applications and research trends.

• The Korean Journal of Pain
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• v.18 no.1
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• pp.1-9
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• 2005

Background: Spinal metabotropic glutamate receptors (mGluRs) and opioid receptors are involved in the modulation of nociception. Although opioid receptors agonists are active for pain, the effects of the compounds for the mGluRs have not been definitely investigated at the spinal level. We examined the effects of the intrathecal mGluR compounds and morphine in the nociceptive test, and then we further clarified the role of the spinal mGluRs. In addition, the nature of the pharmacological interaction after the coadministration of mGluRs compounds with morphine was determined. Methods: Catheters were inserted into the intrathecal space of male SD rats. For the induction of pain, $50{\mu}l$ of 5% formalin solution or a thermal stimulus was applied to the hindpaw. An isobolographic analysis was used for the evaluation of the drug interaction. Results: Neither group I mGluR compounds nor group III mGluR compounds produced any antinociceptive effect in the formalin test. The group II mGluR agonist (APDC) had little effect on the formalin-induced nociception. The group II mGluR antagonist (LY 341495) caused a dose-dependent suppression of the phase 2 flinching response on the formalin test, but it did not reduce the phase 1 response of the formalin test nor did it increase the withdrawal latency of the thermal stimulus. Isobolographic analysis revealed a synergistic interaction after the intrathecal delivery of a LY 341495-morphine mixture. Conclusions: These results suggest that group II mGluRs are involved in the facilitated processing at the spinal level, and the combination of LY 341495 with morphine may be useful to manage the facilitated pain state.

• The Korean Journal of Pain
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• v.27 no.2
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• pp.139-144
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• 2014

Background: To manage intractable cancer pain, an alternative to systemic analgesics is neuraxial analgesia. In long-term treatment, intrathecal administration could provide a more satisfactory pain relief with lower doses of analgesics and fewer side-effects than that of epidural administration. However, implantable drug delivery systems using intrathecal pumps in Korea are very expensive. Considering cost-effectiveness, we performed epidural analgesia as an alternative to intrathecal analgesia. Methods: We retrospectively investigated the efficacy, side effects, and complications of epidural morphine and local anesthetic administration through epidural catheters connected to a subcutaneous injection port in 29 Korean terminal cancer patients. Patient demographic data, the duration of epidural administration, preoperative numerical pain rating scales (NRS), side effects and complications related to the epidural catheterization and the drugs, and the numerical pain rating scales on the 1st, 3rd, 7th and 30th postoperative days were determined from the medical records. Results: The average score for the numerical pain rating scales for the 29 patients decreased from $7{\pm}1.0$ at baseline to $3.6{\pm}1.4$ on postoperative day 1 (P < 0.001). A similar decrease in pain intensity was maintained for 30 days (P < 0.001). Nausea and vomiting were the most frequently reported side effects of the epidural analgesia and two patients (6.9%) experienced paresthesia. Conclusions: Epidural morphine and local anesthetic infusion with a subcutaneous pump seems to have an acceptable risk-benefit ratio and allows a high degree of autonomy to patients with cancer pain.

• Journal of Pharmaceutical Investigation
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• v.21 no.4
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• pp.215-222
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• 1991

The absorption characteristics of itraconazole, which is an antifungal agent, from intestinal segments in the anesthetized rat i1l situ were investigated in order to design an effective oral drug delivery system. The pH-solubility profile of itraconazole, the rate and extent of absorption of itraconazole, the optimal absorption site(s) of itraconazole and the absorption enhancing effect of sodium cholate on itraconazole were examined in the present study. In situ single-pass perfusion method and recirculating perfusion technique using duodenum(D), jejunum(J) and ileum(I) were employed for the calculation of apparent permeability(Pe) and apparent first-order rate constant(Kobs). respectively. The results of this study were as follows; (1) Itraconazole showed appreciable aqueous solubility only at pH values of below 2.0. (2) pe(cm/sec) decreased in the following order: $D(10.24{\pm}1.78{\times}10^{-4})>J(8.86{\pm}0.79{\times}10^{-4})>I(3.78{\pm}0.13 X 10^{-4})$. (3) $Kobs(min^{-1})$ decreased in the following order: $J(17.12{\pm}3.19{\times}10^{-3})>D(13.37{\pm}0.6{\times}10^{-3})>I(11.05{\pm}0.91{\times}10^{-3})$. (4) The solubility of itraconazole markedly increased with the increase of the concentration of sodium cholate. (5) The addition of 10 mM sodium cholate significantly increased the apparent first-order rate constant of itraconazole in the ileum by a factor of 6.8.

• Polymer(Korea)
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• v.29 no.5
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• pp.518-521
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• 2005

Biodegradable polymers and hydrogels have been increasingly applied in a variety of biomedical applications including current drug delivery system and tissue engineering field. ${\alpha},\;{\beta}-Poly$(N-2-hydroxyethyl-DL-aspart-amide), PHEA. is one of poly(amino acids) with hydroxyethyl pendants, which is hewn to be biodegradable and potentially biocompatible. So that, the utilization and various chemical modifications of PHEA have been attempted for useful biomedical applications. In this wort chemical gels based on PHEA were prepared by crosslinking with diisocyanate compound in DMF in the presence of catalyst. Here, the PHEA was prepared from polysuccinimde, the thermal polycondensation product of aspartic acid, via ring-opening reaction with ethanolamine. The preparation of gels and their swelling behavior, depending on the different medium and pH, were investigated. Also the morphology by SEM and simple hydrolytic degradation were observed.

• Polymer(Korea)
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• v.28 no.4
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• pp.344-351
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• 2004

Poly(ethylene glycol)-based diblock and triblock polyester copolymers stimulating to temperature were studied as injectable biomaterials in drug delivery system because of their nontoxicity, biocompatibility and biodegradability. We synthesized the diblock copolymers consisting of methoxy poly(ethylene glycol) (MPEG) (M$_{n}$=750 g/mole) and poly($\varepsilon$-caprolactone) (PCL) by ring opening polymerization of $\varepsilon$-CL with MPEG as an initiator in the presence of HCl . Et$_2$O. The aqueous solution of synthesized diblock copolymers represented sol phase at room temperature and a sol to gel phase transition as the temperature increased from room temperature to body temperature. To confirm the in vivo gel formation, we observed the formation of gel in the mice body after injection of 20 wt% aqueous solution of each block copolymer. After 2 months, we observed the maintenance of gel without dispersion in mice. In this study, we synthesized diblock copolymers exhibiting sol-gel phase transition and confirmed the feasibility as biomaterials of injectable implantation.n.