• Title/Summary/Keyword: Osmotic behavior

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Effect of Trehalose on Biological Membranes with Respect to Phase of the Membranes

  • Park, Jin-Won
    • KSBB Journal
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    • v.32 no.2
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    • pp.103-107
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    • 2017
  • The effect of the trehalose incorporation on the biological membranes was investigated with respect to the phase of the membranes using the fluorescence intensity change. Spherical phospholipid bilayers, vesicles, were prepared only with the variation in the phase of each layer via a double emulsion technique. In the aqueous inside of the vesicles, 8-Aminonaphthalene-1,3,6-trisulfonic acid disodium salt(ANTS) was encapsulated. As a quencher, p-Xylene-bis(N-pyridinium bromide)(DPX) was included in the buffer where the vesicles were dispersed. The fluorescence scale was calibrated with the fluorescence of ANTS vesicles in p-Xylene-bis(N-pyridinium bromide)(DPX)-included-buffer taken as 100% fluorescence and the mixture of ANTS and DPX in the buffer as 0% fluorescence. Trehalose injection into the vesicle solution led the distortion of the membrane. It was found that the distortion was related to the phase of each layer the vesicle up on the ratio of trehalose to lipid. In the identical measurements at glucose, the behavior of the distortion was completely different from that of trehalose. These results seem to depend on the stability of the vesicles, due to the osmotic and volumetric effects on the headgroup packing disruption.

A Study on Elongation/Contraction Behavior and Mechanical Properties of Oxy-Polyacrylonitrile(PAN) Fiber in Basic/Acidic Solution for Artificial Muscle Applications (산화된 폴리아크릴로니트릴 섬유의 인공근육 응용을 위한 염기/산 용액에서의 신장/수축 거동과 기계적 특성 연구)

  • 이영관;김상완;이경섭;조인희;이주화
    • Polymer(Korea)
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    • v.26 no.4
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    • pp.468-476
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    • 2002
  • Oxy-PAN fiber prepared from the preoxidation and saponification of raw PAN fiber is known to elongate and contract when immersed in basic and acidic solutions, respectively. In this study, about 30% elongation in NaOH solution and 30∼50% contraction in HCl solution have been observed. In mechanical test, the mechanical properties of oxy-PAN fiber in the contracted state was stronger than that in the elongated state. These behaviors and mechanical properties are compared to those of living muscle and linear actuator. The change of length in NaOH and HCl solutions is due to switching between a hydrophilic and a hydrophobic structure. Other reasons are exchange of ion and water in/out of oxy-PAN fiber, and osmotic pressure difference associated with relevant ions. Much studies are needed to clarify the effective factors on but the oxy-PAN fiber's elongation/contraction behavior and mechanical properties, but the oxy-PAN fiber perpared in our laboratory has a sufficient potential for application as artificial muscle and linear actuator.

Effect of Sustained Release Recombinant Bovine Somatotropin on Semen Characteristics and Sexual Behavior in Dairy Young Bulls (소 성장호르몬 투여가 젖소 후보 종모우의 정액 성상 및 성 행동 양식에 미치는 영향)

  • Jeong, J.;Shin, J.S.;Kim, J.B.;Yang, B.K.;Hong, B.J.
    • Korean Journal of Animal Reproduction
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    • v.20 no.2
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    • pp.197-205
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    • 1996
  • This study was conducted to examine the effect of sustained release recombinant bovine somatotropin(SR-rBST) with different dosage(0, 0.03mg/kg body weight/14 day, 0.06mg/kg body weight/14 day, 0.09mg/kg body weight/14 day) on the economical traits of the semen characteristics and sexual behaviors and blood chemical values with sixteen Holstein dairy young bulls in Dairy Cattle Improvement Center of National Livestock Co-operatives Federation. Sensual testings of collected semens of Holstein young bulls were not different among treatments (p>0.05). Ejaculated semen volumes of control, SR-rBST 0.03mg, 0.06mg and 0.09mg groups were 5.6ml, 5.6ml, 6.0ml and 6.7m, respectively, but the result of SR-rBST 0.09mg group significantly increased semen volume(P<0.05). In sperm concentration, SR-rBST 0.06mg and 0.09mg groups significantly increased the total number of sperms than the other groups(P<0.05). In otherwise, SR-rBST treatments did not affect on pH, osmotic pressure, anti forzen rate, abnormality and motility of collected semen during whole experimental period. Reaction time(RT), sexual aggressiveness(SA) and tactile stimulation(TS) were not different among treatments. The libido scores(LS) of control, 0.03mg, 0.06mg and 0.09mg groups were 68.0, 80.5, 73.9 and 80.8, respectively, and LS were significantly improved by SR-rBST administration(P<0.05). The effect of SR-rBST on scrotal circumference measurement that is important factor to determine the ability of semen production, was not different among treatments. These studies indicates that SR-rBST treatments favourably affect on semen quality and sexual libido in Holstein young bull.

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Synthesis of N-Stearyl lactobionamide(N-SLBA) and Preparation of Neo-galactosylated Liposome (N-스테아릴락토비온아미드의 합성과 이를 이용한 리포좀의 제조)

  • Kim, Chong-Kook;Min, Mi-Hong;Min, Kyoung-Hee;Lah, Woon-Ryong;Lee, Bong-Jin;Kim, Yang-Bae
    • YAKHAK HOEJI
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    • v.36 no.2
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    • pp.159-166
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    • 1992
  • A neoglycolipid, N-stearyl lactobionamide(N-SLBA) was synthesized and the incorporation of the neoglycolipid into liposomes was achieved in order to prepare neo-galactosylated liposome as potential drug carrier for active targeting to galactose receptor existing cell and tissue. N-SLBA was synthesized by the covalent linkage between carboxyl group of lactobionic acid and amino group of stearylamine(SA). The yield of N-SLBA was about 52.3%. It was identified with $1650\;cm^{-1}$ in IR chart, 7.5 ppm in NMR spectra, $61^{\circ}C$ endothermic peak in DSC heating curve. Surface-modified large unilamellar vesicle with galactose(N-SLBA-LUV) could be prepared with N-SLBA by reverse evaporation method. N-SLBA-LUV was identified by TEM and measuring of membrane function. The maximum amount of N-SLBA incorporated into liposome is up to about 15 mol%. Compared with control liposome (SA-LUV), N-SLBA-LUV showed lower encapsulation efficiency of MTX. It might due to the loss of positive surface charge of stearylamine. N-SLBA-LUV was similar to SA-LUV in aspect of osmotic behavior. N-SLBA-LUV prepared with N-SLBA would be expected to be a good carrier for active targeting to galactose receptor existing cell and tissue.

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Effect of hydroxybutyric-acid on lipid bilayers with respect to layer phase

  • Lee, Gaeul;Park, Jin-Won
    • Journal of the Korean Applied Science and Technology
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    • v.39 no.5
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    • pp.720-726
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    • 2022
  • The behavior changes of the lipid bilayer, induced by the hydroxybutyric-acid incorporation, were investigated with respect to each phase of the layer using fluorescence intensity change. Spherical phospholipid bilayers, called vesicles, were prepared using an emulsion technique. Only in the aqueous inside of the vesicles was encapsulated 8-Aminonaphthalene-1,3,6-trisulfonic-acid-disodium-salt(ANTS). p-Xylene-bis-N-pyridinium-bromide(DPX) was included as a quencher only outside of the vesicles. The fluorescence scale was calibrated with the ANTS-encapsulated vesicles in DPX-dispersed-buffer taken as 100% and the mixture of ANTS and DPX in the buffer as 0%. Hydroxybutyric-acid addition into the vesicle solution led the change in the bilayer. The change was found to be related to the phase of each layer according to the ratio of hydroxybutyric-acid to lipid. These results seem to depend on the stability of the vesicles, due to the osmotic and volumetric effects on the arrangement in both head-group and tail-group.

Oral tissue response to soft tissue expanders prior to bone augmentation: in vitro analysis and histological study in dogs

  • Yoo, Jung Min;Amara, Heithem Ben;Kim, Min Kyoung;Song, Ju Dong;Koo, Ki-Tae
    • Journal of Periodontal and Implant Science
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    • v.48 no.3
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    • pp.152-163
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    • 2018
  • Purpose: To determine whether the swelling and mechanical properties of osmotic self-inflating expanders allow or not the induction of intraoral soft tissue expansion in dogs. Methods: Three different volumes (0.15, 0.25, and 0.42 mL; referred to respectively as the S, M, and L groups) of soft tissue expanders (STEs) consisting of a hydrogel core coated with a silicone-perforated membrane were investigated in vitro to assess their swelling behavior (volume swelling ratio) and mechanical properties (tensile strength, tensile strain). For in vivo investigations, the STEs were subperiosteally inserted for 4 weeks in dogs (n=5). Soft tissue expansion was clinically monitored. Histological analyses included the examination of alveolar bone underneath the expanders and thickness measurements of the surrounding fibrous capsule. Results: The volume swelling ratio of all STEs did not exceed 5.2. In tensile mode, the highest mean strain was registered for the L group ($98.03{\pm}0.3g/cm$), whereas the lowest mean value was obtained in the S group ($81.3{\pm}0.1g/cm$), which was a statistically significant difference (P<0.05). In addition, the S and L groups were significantly different in terms of tensile strength ($1.5{\pm}0.1g/cm$ for the S group and $2.2{\pm}0.1g/cm$ for the L group, P<0.05). Clinical monitoring showed successful dilatation of the soft tissues without signs of inflammation up to 28 days. The STEs remained volumetrically stable, with a mean diameter in vivo of 6.98 mm, close to the in vitro post-expansion findings (6.69 mm). Significant histological effects included highly vascularized collagen-rich fibrous encapsulation of the STEs, with a mean thickness of $0.67{\pm}0.12mm$. The bone reaction consisted of resorption underneath the STEs, while apposition was observed at their edges. Conclusions: The swelling and mechanical properties of the STEs enabled clinically successful soft tissue expansion. A tissue reaction consisting of fibrous capsule formation and bone loss were the main histological events.