• Title/Summary/Keyword: gel diffusion

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Adaptive thresholding noise elimination and asymmetric diffusion spot model for 2-DE image analysis

  • Choi, Kwan-Deok;Yoon, Young-Woo
    • 한국정보컨버전스학회:학술대회논문집
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    • 2008.06a
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    • pp.113-116
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    • 2008
  • In this paper we suggest two novel methods for an implementation of the spot detection phase in the 2-DE gel image analysis program. The one is the adaptive thresholding method for eliminating noises and the other is the asymmetric diffusion model for spot matching. Remained noises after the preprocessing phase cause the over-segmentation problem by the next segmentation phase. To identify and exclude the over-segmented background regions, il we use a fixed thresholding method that is choosing an intensity value for the threshold, the spots that are invisible by one's human eyes but mean very small amount proteins which have important role in the biological samples could be eliminated. Accordingly we suggest the adaptive thresholding method which comes from an idea that is got on statistical analysis for the prominences of the peaks. There are the Gaussian model and the diffusion model for the spot shape model. The diffusion model is the closer to the real spot shapes than the Gaussian model, but spots have very various and irregular shapes and especially asymmetric formation in x-coordinate and y-coordinate. The reason for irregularity of spot shape is that spots could not be diffused perfectly across gel medium because of the characteristics of 2-DE process. Accordingly we suggest the asymmetric diffusion model for modeling spot shapes. In this paper we present a brief explanation ol the two methods and experimental results.

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Purification of Therapeutic Serums of Snake Anti-Venom with Caprylic Acid

  • Norouznejad, Nilofar;Zolfagharian, Hossein;Babaie, Mahdi;Ghobeh, Maryam
    • Journal of Pharmacopuncture
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    • v.25 no.2
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    • pp.114-120
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    • 2022
  • Objectives: Antivenom serums have been used extensively for over a century and are the only effective treatment option for snake bites and other dangerous animal envenomations. In therapeutic serum centers, a wide range of antivenoms is made from animal serum, mainly equine and sheep, that are immunized with single or multiple venoms. This work aimed to use caprylic acid (CA) to purify therapeutic snake antivenom. Methods: Plasma was obtained from equine immunized with a mixture of venoms. Immunized plasma was obtained by precipitation of different concentrations (2-5%) of CA. This methodology was compared to that based on ammonium sulfate (AS) precipitation. Sediment plasma proteins were purified by ion-exchange chromatography. Protein assay, SDSPAGE, and agar gel diffusion were performed. Results: The total protein precipitation with AS was higher than precipitation with CA, but the best results were obtained when CA was added to the plasma until a final CA concentration of 5% was reached. Chromatography and electrophoresis indicated a stronger band for the 5% CA, and the gel diffusion assay showed antigen-antibody interaction in the purified serum. Conclusion: The use of CA compared to the routine method for purifying hyperimmune serums is a practical and cost-effective method for preparing and producing therapeutic serums. It constitutes a potentially valuable technology for alleviating the critical shortage of antivenom in Iran.

Targeted and sustained delivery of hydrocortisone to normal and stratum corneum-removed skin without enhanced skin absorption using a liposome gel

  • Kim, Moon-Kyoung;Chung, Suk-Jae;Lee, Min-Hwa;Cho, Ae-Ri;Shim, Chang-Koo
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.278-278
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    • 1996
  • Judging from hydrocortisone concentration in dosing area, the extent of absorption was reduced in the liposome-gel formulation. However, higher and sustained skin concentrations of hydrocortisone were achieved for the liposome-gel as compared to the ointment. Drug concentration in both viable and deep skin reached its maximum within 0.5 h after application of both formulations to both skin types. Drug concentrations in both skins from the ointment declined with time, while those from the liposome-gel were greatly sustained. The sustainment by the liposome-gel was more remarkable in the viable skin than in the deep skin. Drug concentration in the viable skin could be maintained at a nearly constant level for over 8 h by applying the liposome-gel. As a result, a 5-fold higher viable skin drug concentration was obtained from the liposome-gel than from the ointment at 8 h after the application to the SC-removed skin. However, the plasma concentration of hydrocortisone at 4 h from the liposome-gel was only one-fourth (p<0.01) the value from the ointment when the drug was applied to the SC-removed skin, consistent with. the lower urinary (one-third, p<0.05) and fecal (one-half, p<0.05) excretion. Conclusions : Retarded diffusion of the drug from the skin to the systemic blood stream appears to be a potential factor in the sustained skin concentration of hydrocortisone from the liposome-gel, Interaction of hydrocortisone in the skin with phosphatidylcholine, a component of the liposomes and skin, may well be a factor in retarding the diffusion of the drug in the skin.

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Synthesis of Silica/Alumina Composite Membrane Using Sol-Gel and CVD Method for Hydrogen Purification at High Temperature (Sol-gel 및 CVD법을 이용한 고온 수소 분리용 silica/alumina 복합막의 합성)

  • 서봉국;이동욱;이규호
    • Membrane Journal
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    • v.11 no.3
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    • pp.124-132
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    • 2001
  • Silica membranes were prepared on a porous ${\alpha}$-alumina tube with pore size of 150nm by sol-gel and chemical vapor deposition(CVD) method for hydrogen separation at high temperatures. Silica and ${\gamma}$-lumina membranes formed by the sol-gel method possessed a large amount of mesopores of a Knudsen diffusion regime. In order to improve the $H_2$ selectivity, silica was deposited in the sol-gel derived silica/${\gamma}$-alumina layer by thermal decomposition of tetraethyl orthosilicate(TEOS) at $600^{\circ}C$. The CVD with forced cross flow through the porous wall of the support was very effective in plugging mesopores that were left unplugged in the membranes. The CVD modified silica/alumina composite membrane completely rejected nitrogen permeation and thus showed a high $H_2$ selectivity by molecular sieve effect. the permeation of hydrogen was explained by activated diffusion and the activation energy was 9.52kJ/mol.

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Glucose Analysis Using Free and Immobilized Glucose Oxidase Electrode (고정화 효소전극을 이용한 포도당분석)

  • Jang, Ho-Nam;Ju, Dae-Gwon;Kim, Yeong-Seong
    • Journal of Biomedical Engineering Research
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    • v.3 no.2
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    • pp.95-100
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    • 1982
  • Glucose oxidase from A. niger was entrapped in polyacrylamide gel which was used in the enzyme electrode for glucose analysis. The electrode was assembled by placing the gel between the membranes on the surface of a Clark type electrode. In order to make it possible to analyze the experimental results later, the stagnation flow was adopted wheree the governing fluid mechanics were well known. The current increased with the increase concentration in the bulk below a certain level of glucose concentration beyond which no more current increase was observed. This is probably due to the diffusion limitation of oxygen from the bulk solution. Also the current increased witll the enzyme loading in the gel, but the linearity between the current and the glucose concentration was rather limited to a narrow range. Flow rate was found to be very important, which means that film diffusion is very important under the flow rate of 5cm/sec. As a conclusion, enzyme loading, gel layer thickness, stirring speed and bulk concentration of glucose were found to be most improtant parameters in yielding a linar current reponse with respect to the bulk glucose concentration.

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Bacterial Pattern Formation in Response to the Stiffness of Substrates (접촉 표면의 강성 변화에 따른 박테리아의 군집 패턴)

  • Kim, J.K.;Park, E.J.;Kim, S.R.;Cho, M.Y.;Han, H.
    • 한국가시화정보학회:학술대회논문집
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    • 2007.11a
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    • pp.88-91
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    • 2007
  • Animal cells show different behaviors in response to the mechanical properties of the substrates. We hypothesize that the rigidity of the substrates also affects the bacterial motility and controls the colony dynamics. It is found that the colony size of Escherichia colis and Bacillus subtilis grown on the agar plates is correlated with agarose gel concentrations and thus with the substrate rigidity. High- resolution microscopic imaging reveals that bacteria in single colonies form different aggregation patterns on the agar plates with varying gel concentration. We measured the apparent diffusion coefficients in the agarose gel plates made with different gel concentrations. Mathematical modeling and quantitative imaging of dye dispersion in the agar plates suggest that there is a close connection between the diffusion rate and the colony size. Nanoscale pore structures and kinetic constraints in the porous media may have an effect on bacterial colony dynamics.

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Behavior of Bacteria on the Porous Substrates: Diffusion Effect (다공성 매질 표면에서 박테리아의 거동: 확산의 영향)

  • Cho, Myoung-Ock;Cho, Ji-Yong;Park, Eun-Jung;Lee, Dong-Hee;Lee, Jeong-Hoon;Kim, Jung-Kyung
    • Journal of the Korean Society of Visualization
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    • v.6 no.2
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    • pp.45-50
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    • 2008
  • It has been found that the colony size of bacteria grown on an agar plate decreases with increasing agar gel concentration. Evidenc from recent studies suggests that the bacterial colony dynamics is closely related with the mechanical properties of the substrate. We investigate whether bacterial growth on the agar substrate is controlled mostly by the nutrients' diffusion which is hindered more in porous medium than in solution. The number of bacterial cells in single colonies is found to be inversely correlated with agar concentration. High-resolution live cell imaging at the single bacterium level confirms that the bacterial growth rate is reduced with increasing agar concentration. There is a strong correlation between the slowed diffusion and the reduced number of cells in a high concentration of agar medium.

EFFECT OF PHOSPHORIC ACID CONCENTRATION ON THE DIFFUSION OF HEMA THROUGH DENTIN (상아질을 통한 HEMA의 확산에 인산농도가 미치는 영향)

  • Yoon, Mi-Ran;Lee, Kwang-Won;Park, Soo-Joung
    • Restorative Dentistry and Endodontics
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    • v.24 no.1
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    • pp.147-155
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    • 1999
  • The purpose of this study was to investigate the effect of phosphoric acid concentration on the movement of 2-hydroxyethylmethacrylate(HEMA) from bonding resin - resin composite combination through dentin in vitro. Freshly extracted human third molar teeth were divided into four groups each of 10 teeth. A closed chamber with 1 ml distilled water was attached to the CEJ of each tooth. An occlusal cavity of 4mm diameter & remaining dentin thickness of 1.0-1.5mm was prepared in each tooth. Dentin was treated with 10% phosphoric acid gel for 15 seconds. 32% phosphoric acid gel for 15 seconds, or with 35% phosphoric acid gel for 15 seconds. A control group not treated with acid gel was also prepared. The cavities were rinsed, dried and then treated with the HEMA-containing All-Bond 2 primer & bonding resin which was light-cured for 10 seconds. The cavities were then restored with Z100 composite resin(shade:A3.5:3M Dent. Prod. USA) & light cured for 30 seconds. Water samples were retrieved from the chambers over a time course (4.32, 14.4, 43.2, 144 & 432 minutes ; 1, 3 & 10 days) and analyzed by high performance liquid chromatography. The results were as follows. 1. HEMA was detected in the pulp chambers of all teeth from 4.32 minutes after resin placement The highest rate of release was in the first sample period (0-4.32 min) & rate of release declined exponentially thereafter. 2. No significant differences were found for mean release rate for HEMA over a time course among the four groups (p>0.05). 3. The diffusion rate was significantly (p<0.05) less for 10% phosphoric acid gel than 32% phosphoric acid gel at the second sample period(4.32-14.4 min). 4. No significant differences were found for cumulative HEMA diffusion among the four groups at 10 days(p>0.05) and mean total(cumulative) release at 10 days for all groups was in the 9 - 16 nmol range. 5. The cumulative release was significantly (p<0.05) less for 10% phosphoric acid gel than 32% phophoric acid gel at the third(14.4-43.2 min) & fourth(43.2-144 min) sample period.

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A Release Test for Gels Containing Ketoprofen (겔제제로부터 케토프로펜의 방출특성 시험법)

  • Kim, Ho-Jeong;Yun, Mi-Ok;Lee, Su-Jung;Choi, Hyun-Chul;Kim, Ji-Young;Kim, In-Wha;Shim, Chang-Koo;Kang, Shin-Jung
    • Journal of Pharmaceutical Investigation
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    • v.32 no.2
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    • pp.103-106
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    • 2002
  • A method that describes the determination of the in vitro release of ketoprofen from gels was suggested. The experimental system of the method consists of a Franz diffusion cell, which contains a pH 7.4 phosphate buffer as a receptor medium, and a $70\;{\mu}m$ mesh woven nylon membrane as a diffusion barrier. Under the given condition of the system, the diffusion of ketoprofen across the membrane was rapid enough that the apparent release profile of ketoprofen obtained from the present method could represent the release of the drug from gel preparations. The release of ketoprofen in the present method was reproducible, and the rate increased in proportion to the concentration of ketoprofen in the gel. These suggest that the present method is applicable to the quality evaluation of gel preparations containing ketoprofen.

The Introduction of Polycrylamide Gel into the Solid Culture of Streptomyces spp

  • Han, Hong-Ui;Yang, Moon
    • Korean Journal of Microbiology
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    • v.30 no.1
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    • pp.65-69
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    • 1992
  • It is proposed the polyacrylamide gel, instead of agar, could be used for the solid cultures of microorganisms including Streptomyces strains. Polymerization and gellation of 5% acrylamide solution were done by autoclaving for 5 min at 121.deg.C and no hindered by the addition of nutrient-rich media. In particular, pH buffer solution suitable for corresponding microorganisms must be used in the preparation of culture media. Comparing with agar, it was discussed that polycrylamide gel had many advantages such as gellation within the wide range of strong acid Carbon and Nitrogen sources, requirement tests of growth factors and minerals, sterization at high temperature, diffusion assays of products depending on the pore size of gel, and stability and standarization of microbial cultures.

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