• Journal of the Korean Chemical Society
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• v.40 no.3
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• pp.173-179
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• 1996

Transmission Electron Microscopy (TEM) was used to monitor the response of vesicle size and the intervesicle agglomeration with a variety of experimental parameters. Considered parameters are: (a) reaction temperture, (b) concentration of phosphatidylcholine, (c) concentration of aluminum ion with fixed concentration of phosphatidylcholine at 0.39 mM, and (d) mixed concentration of aluminum and phosphatidylcholine when fixing the weight ratio of phosphatidylcholine to aluminum at 0.01. Controlling these parameters, vesicle size changed and intervesicle agglomeration observed. As reaction temperature and the concentration of phosphatidylcholine increase, vesicle size decreases. With 0.2 M of aluminum ion, abnormal vesicle growth led by intervesicle agglomeration and coalescence was observed. When weight ratio of phosphatidylcholine to aluminum is 0.01, optimal vesicle size and size distribution can be obtained.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.59-64
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• 2011

Degree of unsaturation in fatty acid molecules plays an important role in the formation of vesicles. Vesicle formation from C18 fatty acids with different amount of double bonds such as oleic acid, linoleic acid and linolenic acid with the incorporation of 1,2-dipalmitoyl-sn-glycerol-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DPPE-PEG2000) have been examined by TEM. Critical vesicular concentrations (CVC) of the vesicle suspension are determined by turbidity and surface tension methods. The CVC of fatty acids increases when the amount of unsaturation in the alkyl chain increases. On the other hand, stability of vesicle suspension has been examined by using particle size and zeta potential at $30^{\circ}C$. There was a dramatic decrease in particle size measurement from mono-unsaturation to tri-unsaturation which could be due to the effect of fluidity in the membrane bilayer caused by different degree of unsaturation. The values of zeta potential for vesicles that were formed without the incorporation of DPPE-PEG2000 were in the range of -70 mV to -100 mV. It has been observed that the incorporation of DPPEPEG2000 to the vesicle reduces the magnitude of zeta potential. However, this phenomenon does not obviously seen in fatty acid vesicles formed by linoleate-linoleic acid and linolenate-linolenic acid. We therefore conclude that the addition of DPPE-PEG2000 does not effectively improve the stability of the linoleate-linoleic acid and linolenatelinolenic acid vesicle at pH 9.0 after the evaluation of their particle size and zeta potential over a period of 30 days. Although the vesicles formed were not stable for more than 10 days, they have displayed the potential in encapsulating the active ingredients such as vitamin E and calcein. The results show that the loading efficiencies of vitamin E are of encouraging value.

• Applied Microscopy
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• v.25 no.2
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• pp.1-10
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• 1995

This study was carried out to clarify the neuronal organization in pineal body of catfish. The pineal body was observed by acetylcholinesterase histochemistry and electron microscopy. The neuronal types observed in the pineal body of catfish were bipolar and multipolar cells. Multipolar cells were found throughout the pineal end vesicle and whole stalk, but bipolar cells only in the end vesicle and distal stalk. The pineal tract was formed by the long axons of these neurons. The neuronal clusters(pineal ganglia) were also observed in the end vesicle. In summary, the type of neurons in catfish pineal was different from that of other species, and the neuronal distribution differed depending on the region of pineal body. These results reflect the interspecific and regional differences of the pineal organization of fishes.

• Journal of Pharmaceutical Investigation
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• v.23 no.2
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• pp.89-95
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• 1993

Polymerized vesicles were prepared from the monomeric cholesterol-containing surfactant. Spacer groups were introduced into [(cholesteryloxy)carbonylmethyl] [2-(methacryloyloxy)ethyl]dimethylammonium chloride (CHODAMA). In case of introducing the spacer groups to the cholesterol moiety, both permeability of vesicles and that of polymerized vesicles were decreased. In case of introducing the spacer groups to monomeric moiety, permeability of vesicles was increased, while that of polymerized vesicles was decreased.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1142-1146
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• 1996

Cholesterol-containing surfactant was synthesized, and it was sonicated with monomer in water to form a vesicle solution. This vesicle solution was dried to construct a membrane which had a molecular multilayer structure. Using UV irradiation the monomer in this membrane were polymerized, and then surfactant was extracted by organic solvent. Using a X-ray diffractometer, the thickness of one layer and the regularity of the multilayer were measured. And scanning electron microscopy was conducted for fractured polymer film.

• Membrane Journal
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• v.6 no.4
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• pp.213-218
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• 1996

Cholesterol-containing monomeric surfactants were synthesized, and sonicated in water to form a vesicle solution. This vesicle solution was dried to construct a membrane which had a molecular multilayer structure. Using UV irradiation the surfactants in this membrane were polymerized and molecular weight was determined. Using a X-ray diffractomelet, the thickness of one layer and the regularity of the multilayer were measured.

• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.380-387
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• 2004

The preparation of $CaSO_4$ nanoparticle by vesicles formed spontaneously in cationic OTAC and anionic ADS mixed surfactant solution whose ratio is 0.3/0.7 is investigated. Added electrolytes for preparing nanoparticles reduce vesicle size about 200-300 nm comparing with that of pure vesicle whose size is 700-800 nm by DLS. The core of vesicles has 200 nm size and acts as nanoreactors which same size of monodisperse $CaSO_4$ nanopaticles are formed. Although $CaSO_4$ particles are formed at the outer of vesicles, they are very large and amorphous. The formed particles are identified with XRD analysis after separation due to coinciding with $CaSO_4$ particles.

• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.247-250
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• 2011

The excess volumes of mixing of benzyl alcohol and halothane in vesicle and in suspensions of several lipids have been determined at $25^{\circ}C$ it using a excess volume dilatometer. The potency of general anesthetics has long been known to correlate with lipid solubility. Denaturations of the vesicle, which is a sole membrane protein in the purple membrane of Halobacteriun Halobium, were studied by absorption changes at 280 nm and fluorescence changes at 330 nm and excess volume dilatometer. The particle size analysis of viscous polymer solutions by diffusional interchange is the key step by measurement. The excess volume of mixing in chitosan was found to be negative, whereas them of purple membrane, Halobacteriun Halobium and red membrane were positive in benzyl alcohol and halothane. This result was confirmed as Miller's supposition.

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.48-51
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• 2008

Dipalmitoyl phosphatidyl choline and p-nitrophenyl palmitate were directly sonicated in acidic water for 6 minutes to give clear stock solutions. The catalytic hydrolysis of p-nitrophenyl palmitate was studied at $30-50^{\circ}C$ in the presence of unilamellar vesicle and mixture of unilamellar and multilamellar aggregates. The difference of reaction rate between unilamellar and multilamellar was observed. The rate of unilamellar reaction compared to the rate of mixture reaction showed more catalytic effect. The phase transition temperature of vesicle was measured at $37-44^{\circ}C$.

• Development and Reproduction
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• v.18 no.3
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• pp.161-166
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• 2014

Previously, we demonstrated that the shift and/or restriction of feeding time during relatively short-term period (4 weeks) could alter the pituitary gonadotropin expression and the weights of seminal vesicle and prostate in rats. We also found that the reverse feeding (RF) schedule (up to 8 weeks) might induce an adaptable metabolic stress and cause impairment of androgen-dependent reproductive tissues. In the present study, we extended the RF time regimen up to 12 weeks, and measured the reproductive tissue weights. After 4 and 8 weeks of RF, the weights of epididymis were not significantly different. After 12 weeks, however, epididymis weights of RF animals were significantly different (CON 12W : RF 12W = $48.26{\pm}0.62mg$ : $44.05{\pm}1.57mg$, p<0.05). After 4 and 12 weeks of feeding, seminal vesicle weights of RF animals were significantly decreased (CON 4W : RF 4W = $79.36{\pm}8.34mg$ : $46.28{\pm}2.43mg$, p<0.001; CON 12W : RF 12W = $72.04{\pm}3.76mg$ : $46.71{\pm}2.27mg$, p<0.001, respectively). Prostate weights were not changed by RF. Kidney and spleen weights of RF animals were significantly different on weeks 4 and 12 (Kidney, CON 4W : RF 4W = $249.72{\pm}4.20mg$ : $228.41{\pm}3.03mg$, p<0.001; CON 12W : RF 12W = $309.15{\pm}7.49mg$ : $250.72{\pm}6.13mg$, p<0.001, respectively, Spleen, CON 4W : RF 4W = $111.26{\pm}3.76mg$ : $96.88{\pm}4.69mg$, p<0.05; CON 12W : RF 12W = $123.93{\pm}10.72mg$ : $94.68{\pm}5.65mg$, p<0.05, respectively). Histology analysis of seminal vesicle revealed that the thinner epithelial cell layers, reduced complexities of swollen papilla folding in the exocrine glands on weeks 4 and 12 of RF. There was no histological difference between control and RF group on week 8. The present study indicates that up to 12 weeks RF induced differential changes in tissue weights of male mice. In particular, seminal vesicle, kidney and spleen seemed to temporarily adapted to the RF-induced metabolic stress on week 8 of feeding schedule. These results confirmed the our previous study that the RF might induce an adaptable metabolic stress and cause impairment of androgen-dependent reproductive tissues such as epididymis and seminal vesicle as well as non-reproductive tissues such as kidney and spleen. Further studies will be needed to achieve a better understanding of the how does mealtime shift affect the reproductive function and exact nature of adaptation.