• Title/Summary/Keyword: Capillary barrier

Search Result 49, Processing Time 0.035 seconds

Simulations of LNAPL flow and distribution in heterogeneous porous media under dynamic hydyogeologic conditions

  • Cheon, Jeong-Yong;Lee, Jin-Yong;Lee, Kang-Kun
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 1999.10a
    • /
    • pp.39-43
    • /
    • 1999
  • 불포화대에서 LNAPL의 이동과 분포를 수치 모의를 통하여 예측하였다. 균질한 매질에서 LNAPL의 이동은 조립질 매질에서 빠르고, 세립질 매질에서 더 많은 면적으로 확산되며, 더 많은 LNAPL이 불포화대에 잔류한다. 조립질 매질내에 세립질층이 존재할 경우, 이 층이 지하수면으로부터 멀수록 LNAPL이 많이 포획된다. 조립질 매질에 세립질 또는 더 조립질인 매질이 렌즈 상으로 존재하는 환경에서는, LNAPL이 이들 렌즈를 통과하지 못한다. 불균질한 렌즈가 존재할 때의 LNAPL 분포를 초기조건으로 이용하여, 지하수 면의 수직 이동과 물의 침투에 따른 LNAPL의 이동을 모의하였다. 두 경우 모두 불포화대에 잔류되어 있던 LNAPL의 수직방향 이동이 증가되었다. 특히, 지하수면의 하강 시 LNAPL이 조립질 렌즈를 통해 이동하나, 세립질 렌즈를 통해서는 이동하지 못한다.

  • PDF

Fluidic Manipulating in Microchannels Using Hydrophobic Patterns (소수성 패턴을 이용한 미세유로에서의 유체 조작)

  • Lee, Sang-Ho;Kim, Yong-Kweon
    • Proceedings of the KIEE Conference
    • /
    • 2000.11c
    • /
    • pp.583-585
    • /
    • 2000
  • This study reports the fluidic handling method using hydrophobic patterns inside PDMS microchannels. In order to obtain hydrophobic patterns, we pattern fluorcarbon(FC) film surfaces by lift-off process. FC films are deposited by spin coating method and plasma polymerization method. Hydrophobic surfaces are used as the barriers to control fluid flow. Injected liquid is spontaneously filled up inside PDMS-microchannels by the capillary action. Liquid flow stops when it meets hydrophobic regions which can be the barrier against fluid flow. Then, again, when liquid is pressurized externally, liquid can move toward another hydrophilic region by external air pressure. Contact angle analyses are performed on fluorocarbon films to estimate the wettability of film surfaces.

  • PDF

Brain Uptake and the Analgesic Effect of Oxytocin - its Usefulness as an Analgesic Agent

  • Kang, Young-Sook;Park, Ji-Hyun
    • Archives of Pharmacal Research
    • /
    • v.23 no.4
    • /
    • pp.391-395
    • /
    • 2000
  • To establish the usefulness of oxytocin (OT) as an analgesic for women in delivery, the pharmacokinetic parameters and blood-brain barrier (BBB) permeability of [$^3H$] OT were obtained using an intravenous injection technique or the internal carotid artery perfusion/capillary depletion (ICAP/CDM) method. Brain uptake of OT was similar to that of sucrose, plasma space marker, indicating that OT has a poor BBB permeability. Moreover, the analgesic effects of OT injected through the jugular vein on nociception were evaluated by the tail-flick method. The antinociceptive effects of OT injected at a dose of 0.2 ${m}g/kg$or 2 ${m}g/kg$ were dose-dependent. In addition, the analgesic effects of OT on the CNS were unaffected by naloxone, a m-receptor antagonist. In a similar manner to the opioid system, OT may play a modulatory role in antinociception.

  • PDF

Transport of choline and its relationship to transport of cationic drugs in immortalized rat brain capillary endothelial cell line

  • Park, Hong-Mi;Lee, Kyeong-Eun;Lee, Na-Young;Kang, Young-Sook
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 2003.11a
    • /
    • pp.106-106
    • /
    • 2003
  • Choline serves critical roles in the CNS both as a precursor of neurotransmitter and as an essential component of membrane phospholipids. The long-term maintenance of brain choline concentration is dependent on choline transport across the blood-brain barrier (BBB), And, we examined to elucidate the characteristics of transport of choline across the BBB using conditionally immortalized rat brain capillary endothelial cell line (TR-BBB) in vitro. The [$^3$H]choline in TR - BBB was increased by time dependently, but independent on Na$\^$+/, and the transport process is saturable with Michaelis-Menten constrant, Km of about 26 ${\mu}$M. The uptake of [$^3$H]choline is susceptible for inhibition by various organic cationic compounds including hemicholinium-3, tetraethylammonium chloride (TEA) and $\ell$-carnitine. Also, we investigated the relationship of transport of choline and cationic drugs. The uptake of [$^3$H]choline is inhibited by antioxidant, a-phenyl-n-tert-butyl nitrone (PBN) with IC$\sub$50/ of 1.2 mM. and by Alzheimer's disease therapeutics, such as acetyl $\ell$-carnitine, tacrine and donepezil. Also, choline uptake presented competitive inhibition with PBN, donepezil and acetyl $\ell$-carnitine in Lineweaver-Burk plot. In conclusion, TR-BBB cells express a saturable transport system for uptake of choline, and several cationic drugs may be transported into the brain by BBB choline transporter.

  • PDF

Brain Delivery of $^{99m}Tc$-Diethylene Triamine Pentaacetic Acid and Phenytoin by Transient Osmotic Opening Method in Rats (흰쥐에서 삼투개열법에 의한 $^{99m}Tc$-Diethylene Triamine Pentaacetic Acid 및 페니토인의 뇌로의 송달)

  • Hwang, Man-Yong;Park, Kyoung-Ho;Lee, Min-Hwa
    • YAKHAK HOEJI
    • /
    • v.42 no.2
    • /
    • pp.196-204
    • /
    • 1998
  • The blood-brain barrier (BBB) of rats was modificated opening reversibly by infusing a hyperosmotic solution of arabinose (1.6 molal) into the right external carotid artery. Pre vious studies demonstrated that permeability was increased maxmmally in the first 15 min and remained slightly elevated at 1 hr. As control reference, saline was used. In the present study, to evaluate the effects of osmotic BBB opening on the BBB trasport according to hydrophilic or hydrophobic characteristics of drugs. And the differences of the uptakes of these compounds to right (treated osmotic opening) and left (untreated) hemispheres in same rats were compared each other following injection of 8 mCi per rat of $^{99m}Tc$-ethylene triamine pentaacetic acid (DTPA) as hydrophilic drug or 5mg/kg of phenytoin as hydrophobic drug mto the right external carotid artery of rats between two groups (1.6 molal arabinose vs saline). The uptakes of $^{99m}Tc$-DTPA and phenytoin in the right cerebral hemispheres were increased to about thirty three times and twice rather than those in the left cerebral heimspheres, respectively. And PAs (permeability X capillary surface area) were also increased from a control mean of 2.11${\times}10^{-4}$ (Untreated) to 6.98${\times}10^{-3}\;sec^{-1}$ (treated osmotic opening for $^{99m}Tc$-DTPA and 0.29 to 0.17 $sec^{-1}$ for phenytoin, respectively. From the results of present study, it is noted that osmotic opening of BBB is more effective in the brain delivery of hydrophilic drugs rather than that of hydrophobic drugs.

  • PDF

The Effects of Ionized Maifanite on Skin Damages of Nc/Nga Mice after Atopic Dermatitis Elicitation (이온화된 맥반석이 아토피 피부염 유발 Nc/Nga mice의 피부손상 및 염증 완화에 미치는 영향)

  • Kim, Jong-Chae;Hong, Seung-Ug
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.30 no.1
    • /
    • pp.29-42
    • /
    • 2017
  • Objectives : Atopic dermatitis accompanies with severe pruritus and collapse of skin barrier, inflammation. Maifanite could be used as an ointment for skin disease. However, there have been few studies about maifanite uses for atopic dermatitis. We report the anti-inflammatory and promoting skin recovery effects of ionized maifanite on damaged skin barrier with experimentally elicited atopic dermatitis. Methods : Nc/Nga mice were divided into 3 groups: control group(CON), atopic dermatitis elicited group(AE group), ionized maifanite treated group after atopic dermatitis elicitation(MT group). After 5% SDS was applied D. pteronyssinus crude extract also applied for 3 weeks to elicit atopic dermatitis-like skin disease. MT group was treated for 3 weeks with ionized maifanite. Ionized maifanite was applied once a day and voluntarily administrated. AE group and control group were treated with normal saline in the same way. Results : In MT group, skin lesions like eczema were more improved than AE group. p-ERK1/2 positive reaction was reduced in MT group. MMP-9 and substance P positive reaction at dermal papillae was also reduced in MT group. With skin angiogram, capillary vessel decreased in MT group. Also, IL-4 positive reaction cell and STAT-6 positive reaction cell reduced more in MT group than in AE group. $NF-{\kappa}B$ p65 positive reaction cell and iNOS positive reaction cell also declined more in MT group than in AE group. Conclusions : It is supposed that ionized maifanite has anti-inflammatory effects on NC/Nga mice's atopic dermatitis with suppressing IL-4 production and Th2 cell differentiation, and controlling $NF-{\kappa}B$ activation.

Industrialization possibilities of purified pig sperm hyaluronidase

  • Soojin Park;In-Soo Myeong;Gabbine Wee;Ekyune Kim
    • Journal of Animal Science and Technology
    • /
    • v.65 no.6
    • /
    • pp.1205-1213
    • /
    • 2023
  • The goals of the present study were to develop a simple method for obtain highly purified pig sperm hyaluronidase (pHyase) and to assess its activity, function, and safety. In mammals, sperm-specific glycophosphatidylinositol (GPI)-anchored Hyase assists sperm penetration through the cumulus mass surrounding the egg and aids in the dispersal of the cumulus-oocyte complex. Recently, Purified bovine sperm hyaluronidase (bHyase) has been shown to enhance therapeutic drug transport by breaking down the hyaluronan barrier to the lymphatic and capillary vessels, thereby facilitating tissue absorption. Commercially available Hyase is typically isolated from bovine or ovine; which have several disadvantages, including the risk of bovine spongiform encephalopathy, low homology with human Hyase, and the requirement for relatively complex isolation procedures. This study successfully isolated highly purified pHyase in only two steps, using ammonium sulfate precipitation and fast protein liquid chromatography. The isolated Hyase had activity equal to that of commercial bHyase, facilitated in vitro fertilization, and effectively dissolved high molecule hyaluronic acid. This simple, effective isolation method could improve the availability of pHyase for research and clinical applications.

Effect of Coptidis Rhizoma extract on Atopic Dermatitis-like Skin Lesions in NC/Nga Mice (황련 추출물의 아토피피부염 유발 생쥐에서 피부손상 완화 효과)

  • Jung, A Ram;Ahn, Sang Hyun;Jeong, Han Sol;Kim, Ki Bong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.33 no.2
    • /
    • pp.102-108
    • /
    • 2019
  • This study aims to evaluate the anti-inflammatory effect of Coptidis Rhizoma (CR) extract for atopic dermatitis through maintaining skin barrier and regulating Th2 cell differentiation. We divided NC/Nga mice into 3 groups as follows; atopy-like dermatitis induced group with CR treatment (CT, n=10), no treatment group(Ctrl), atopy-like dermatitis elicited group(AE). Atopy-like dermatitis was induced to NC/Nga mice by sensitizing with dermatophagoides farinae(DfE) on 7, 8, 9, 11, 12, and 13th week. After inducing atopic dermatitis, CR extract was administered 20 mg/kg daily for the experimental duration to the CT group. We measured the integrity of lipid layers in the epidermis and Th2 differentiation through immunohistochemical staining against filaggrin, loricrin, IL-4, and IL-13. We also measured the distribution of subcutaneous collagen fibers by the Masson's trichrome staining. Administration of CR significantly inhibited the reduction of lipid layers in the skin that caused atopy. The expression of IL-4, IL-13, each of which is a cytokine secreted by T helper type 2 (Th2) cells, was markedly suppressed in the CT group as compared with AE group (p<0.05). CR treatment also decreased the expression of iNOS, $p-I{\kappa}B$. Atopic dermatitis induced dermatological damage to skin, such as hyperplasia of epithelium, and capillary proliferation was significantly reduced by CR administration. CR effectively inhibited the thinning of the skin barrier and inflammatory responses in atopic dermatitis-induced mice. In particular, it showed anti-inflammatory effects by reducing the expression of IL-4 and IL-13, Th2 cell cytokines, which play a crucial role in development of atopic dermatitis. Therefore, CR can be a good candidate to ameliorate and treat atopic dermatitis.

Simulations of the Flow and Distribution of LNAPL in Heterogeneous Porous Media under Water Table Fluctuation Condition (불균질한 다공성 매질에서의 지하수위 변동을 고려한 저밀도 비수용성유체(LNAPL)의 흐름 모의)

  • 천정용;이진용;이강근
    • The Journal of Engineering Geology
    • /
    • v.13 no.1
    • /
    • pp.51-65
    • /
    • 2003
  • A series of numerical simulations were carried out using STOMP( Subsurface Transport over Multiple Phase) simulator. The flow and distribution of LNAPL were analyzed in homogeneous fine and coarse sand. Vertical movement of LNAPL is faster in the coarser sand. But the total volume of LNAPL retained in the unsaturated zone is larger in the finer sand. A fine layer in the coarse sand domain is also simulated. The results showed that the retained LNAPL volume and shape are highly influenced by the Position of the fine layer. Flow and distributions of LNAPL were simulated when there were heterogeneous lenses in the sand domain. Water table fluctuation was also considered. In these cases, it was found that the heterogeneous lens was a barrier to LNAPL flow, and water table fluctuation stimulated the downward movement of retained LNAPL. The LNAPL flow and distribution observed in these numerical experiments show that in the subsurface environment, the behaviors of LNAPL highly depend on heterogeneities of unsaturated zone and the dynamic hydrogeologic condition such as water table fluctuation. These results can explain some of the complexity of LNAPL flow and distribution Patterns in LNAPL contaminated field sites.

Characteristics of Drainage Pervious Block Considering Urban Rainfall (도심지 강우 특성을 고려한 투수성 보도블록의 배수 특성)

  • Seo, Da-Wa;Yun, Tae-Sup;Youm, Kwang-Soo;Jeong, Sang-Seom;Mun, Sung-Ho
    • Journal of the Korean Geotechnical Society
    • /
    • v.31 no.1
    • /
    • pp.53-64
    • /
    • 2015
  • This study presents the experimental results of pervious blocks subjected to a series of unique inflow conditions in urban area. The measured properties include the strength, permeability, drainage capacity and runoff, and evaporation for blocks made of two different size of aggregates. Results revealed that the strength satisfies the Korean Standard regardless of aggregate size whereas the immediate runoff occurred for the block with small size aggregate. On the other hand, the block with large aggregates allowed the drainage upon the initial inflow condition, which became hampered to induce the runoff by subsequent inflow. It was attributed to the fact that the capillary water often served as the hydraulic barrier in partially saturated condition. The salient observation indicated that the runoff highly depended on the evaporation and pre-wetting condition as well as the porosity and pore connectivity. The bilinear evaporate rate that makes the degree of saturation vary also had great influence on deterining the time-dependent runoff.