• Proceedings of the PSK Conference
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• 2001.04a
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• pp.48-55
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• 2001

When an elongating RNA polymerase encounters DNA damage on the template strand of a transcribed gene it can either be arrested by or be transcribed through the lesion. Lesions that arrest RNA polymerases are thought to be subject to transcription-coupled repair, whereas that damage that is bypassed can cause miscoding, resulting in mutations in the transcript (transcriptional mutagenesis). We have developed a technique using a plasmid-based luciferase reporter assay to determine the extent to which a particular type of DNA base modification is capable of causing transcriptional mutagenesis in vivo. The system uses Escherichia coli strains with different DNA repair backgrounds and is designed to detect phenotypic changes caused by transcriptional mutageneis under nongrowth conditions. In addition, this method is capable of indicating the extent to which a particular DNA repair enzyme (or pathway) suppresses the occurrence of transcriptional mutagenesis. Thus, this technique provides a tool with which the effects of various genes on non-replication-dependent pathways resulting in the generation of mutant proteins can be gauged.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.323-333
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• 2007

The degree to which parallel evolution utilizes the same genetic mechanisms indicates the degree to which developmental processes constrain or channel phenotypic evolution. A transgenetic strategy was used to elucidate the role of one floral meristem identity gene, LEAFY (LFY), in the evolution of rosette flowering, a plant architecture that has evolved in parallel in several lineages of the mustard family, Brassicaceae. The LFY genes from three rosette flowering species were cloned and introduced into a species with the ancestral architecture, and results indicated that changes at the LFY locus contributed to the evolution of rosette flowering in two of the three lineages, but that in each lineage a different set of genetic partners was involved. Also, LFY was shown to play a role in the evolution of flower size. Transgenetic strategy may be useful in the study of plant morphological evolution and parallelism.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.99-109
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• 1999

Enteropathogenic Yersina enterocolitica is an important cause of human and animal disease. Phenotypic and genotypic characteristics currently used to identify Yersinia enterocolitica are not necessarily sufficient to differentiate pathogenic from non-pathogenic strains or to analyze the epidemiology of yersiniae at a molecular level. To improve the characterization of Yersinia enterocolitica, A total of 65 isolates of Yersinia enterocolitica were examined with bioserotyping, antibiotic susceptibilities, PFGE, PCR-ribotyping. Genomic DNA pattern generated by PFGE are highly specific for different strains of an organism and have significant value in epidemiologic investigations. The PFGE analysis of Not I-digested chromosomal DNA of Y. enterocolitica were performed with a CHEF Mapper(Bio-Rad, USA). Not I generated 19 restriction endonuclease digestion profiles(REDP). PCR-ribotyping, performed with primers complementry to conserved regions of 16S and 23S rRNA gene, generated 13 ribotypes. PCR-ribotyping can be considered a good technich for subtyping strains of Y.enterocolitica.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.46-47
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• 2006

Vascularization is essential for success in regenerative medicine. We have developed in vitro models to study how human microvascular endothelial cells (EC) and endothelial progenitor cells (EPC) colonize polymer scaffolds and express the endothelial phenotype, including angiogenesis. Examples are given of supportive growth and differeniation of EC on microfibre meshes of the silk protein fibroin and blends of starch with poly(epsilon-caprolactone), phenotypic markers being studied at both protein and mRNA level. Experimental models are also shown and concepts discussed to investigate how the stem cell niche, including that responsible for vascularization could be targeted, for example, by using engineered biodegradable polymer nanoparticles.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.1
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• pp.1-10
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• 2005

Parthenogenesis in mulberry silkworm, Bombyx mori L. acquires immense use in the development of outstanding homozygous lines with higher viability, hybrid vigour, combining ability and less phenotypic variability. It can serve as a powerful tool in controlling sex of the offsprings as well as a useful tool in selection. In fact India is the second largest silk producing country in the world next only to China and all the five types of natural silks viz., mulberry, oak tasar, tropical tasar, muga and eri are produced in India. However, little information is available on the role of artificial parthenogenesis in the development of superior silkworm breeds. This paper overviews some important studies carried out on artificial parthenogenesis, and outline of different types of parthenogenesis, methods of induction of artificial parthenogenesis, factors responsible for successful parthenogenetic development, cytogenetics of artificial parthenogenesis and role of artificial parthenogenesis in silkworm breeding. Besides, an attempt is made to describe briefly about parthenogenetic engineering which includes cloning in silkworm, artificial insemination, chimeras, hybridization, chromosomal substitution and recombinant DNA in silkworm.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.69-73
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• 2003

Specific leaf weight (SLW), defined as the mass of tissue per unit leaf area has been found to be an important physiological parameter as it indicates the relative thickness of leaves. Greater SLW provides more photosynthetic potential per unit area of leaf and hence it is frequently been considered as correlated with photosynthesis in several plant species. Collections of 165 mulberry (Morus sp.) germplasm accessions, both Indian and exotic in origin were evaluated for their variability with respect to SLW. The mean specific leaf weight ranged from 35.3 to $72.3 g/m^{-2}$. The distribution of SLW was found to be normal. High heritability (97.08%) and a small difference between genotypic and phenotypic variance demonstrates the genetic control over SLW. Significant heterotic effect with respect to SLW was observed in crosses when parents with high and low SLW were chosen.

• Korean Journal of Medicinal Crop Science
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• v.10 no.4
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• pp.263-268
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• 2002

Acifluorfen-tolerant callus lines of Solanum ptycanthum were isolated by stepwise selection. Growth of the unselected line was completely inhibited at 0.5 uM. while some selected lines grew at 8 uM acifluorfen. Twenty-two of twenty-five acifluorfen-tolerant callus lines regenerated shoots. Many of the regenerated somaclones were variants, differing in leaf shape, leaf color, number of flower parts, flower color, and fertility. The acifluorfen tolerant S. ptycanthum callus lines differed.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.87-93
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• 2014

Dental plaque resides passively at a site and makes an active contribution to the maintenance of health. The bacterial composition of plaque remains relatively stable despite regular exposure to minor environmental stress. This stability, homeostasis is due to a dynamic balance of microbial interactions. However, the homeostasis can break down, leading to shifts in the balance of the microflora. This change can be a sign of initial dental caries. It is proposed that disease can be prevented or treated not only by targeting the putative pathogens but also by interfering with the processes that drive the breakdown in homeostasis. It is essential to understand the plaque as a mixed species biofilm. In this essay I reviewed an extension of the caries ecological hypothesis to explain the relation between dynamic changes in the phenotypic/genotypic properties of plaque bacteria and the demineralization and remineralization balance of the dental caries process. We will have the strategies to impact significantly on clinical practice as understanding dental biofilm.

• Biomedical Science Letters
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• v.10 no.4
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• pp.333-339
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• 2004

A multiplex PCR assay targeting the yst and 16S rRNA genes of Yersinia enterocolitica was developed to specifically identify pathogenic Y. enterocolitica from pure culture. Simultaneous amplification of 145 and 416 bp fragments of the yst and 16S rRNA genes of Y. enterocolitica was obtained using the primer pairs in a single reaction. Validation of the assay was performed with the reference Yersinia strains and other members of the family Enterobacteriaceae. The defined primer pairs amplified the targeted sequence from only pathogenic Y. enterocolitica strains, whereas none of the other bacterial species yielded any amplified fragments. Within an assay time of 4 h, this assay offers a very specific, reliable, and inexpensive alternative to the conventional phenotypic assays used in clinical laboratories to identify pathogenic Y. enterocolitica.

• Journal of Genetic Medicine
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• v.10 no.2
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• pp.117-119
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• 2013

Double trisomy mosaicism of two different cell lines is extremely rare, particularly those that involve constitutional trisomy 8. We report a case of 47,XXX/47,XX,+8 in a 12-year-old female presenting with several skeletal anomalies. She exhibited distinct phenotypic features such as tall stature, deviation of the left middle finger, webbing of both thumbs and flexion deformities of the both third and fifth distal intermediate phalanges. A mild impulse-control disorder was observed, without mental retardation. Chromosomal and fluorescence in situ hybridization analysis demonstrated double trisomy mosaicism both on lymphocytes and buccal epithelial cells.