Biomedical subjects

Myung-Hoon Chung

Publications and source records attributed to Myung-Hoon Chung.

3 recordsLinked to original sources

PubMed2004

Polymerizable ion-pair amphiphile that has a polymerizable group at cationic ammonium chain.

Polymerizable ion-pair amphiphile (PIPA) that has a polymerizable lipoyl group on cationic ammonium chain was prepared to compare the advantage of ion-pair form with the conventional polymerizable ammonium surfactant in the points of stability of vesicle and permeation properties. PIPA introduced in this paper, compared to previously reported one with polymerizable group on anionic chain side, showed similar vesicle stability in addition to high encapsulation efficiency and resistance to disruption by SDS or Triton X-100. Reasons for such high encapsulation and low permeability of the PIPA vesicle are investigated and the possible applications are briefly discussed.

Anions↗

PubMed2004

Polymerized ion pair amphiphile vesicles with pH-sensitive transformation and controlled release property.

Ion pair amphiphiles (IPA) composed of one proton-deionizable single or double alkyl chain ammonium surfactant and one anionic carboxylate surfactant with polymerizable dithiolane ring are prepared to develop polymerized microcapsules that can recognize pH change and transform itself under basic condition, thus releasing encapsulated materials at the desired point. Combination of pH-sensitivity and polymeric solid structure, if fully developed, endows the IPA vesicle with smart function that is highly valuable in drug delivery application. Reasons for such high pH-sensitive vesicle transformation are sought from combined physical properties such as turbidity, zeta potential, surface tension, and release rate of marker through the vesicle membrane.

Hydrogen-Ion Concentration↗

PubMed2003

Fractional populations in multiple gene inheritance.

MOTIVATION: With complete knowledge of the human genome sequence, one of the most interesting tasks remaining is to understand the functions of individual genes and how they communicate. Using the information about genes (locus, allele, mutation rate, fitness, etc.), we attempt to explain population demographic data. This population evolution study could complement and enhance biologists' understanding about genes. RESULTS: We present a general approach to study population genetics in complex situations. In the present approach, multiple allele inheritance, multiple loci inheritance, natural selection and mutations are allowed simultaneously in order to consider a more realistic situation. A simulation program is presented so that readers can readily carry out studies with their own parameters. It is shown that the multiplicity of the loci greatly affects the demographic results of fractional population ratios. Furthermore, the study indicates that some high infant mortality rates due to congenital anomalies can be attributed to multiple loci inheritance. AVAILABILITY: The simulation program can be downloaded from http://won.hongik.ac.kr/~mhchung/index_files/yapop.htm. In order to run this program, one needs Visual Studio.NET platform, which can be downloaded from http://msdn.microsoft.com/netframework/downloads/default.asp.

Alleles↗