• 한국컴퓨터정보학회논문지
• /
• 제15권12호
• /
• pp.93-100
• /
• 2010

본 논문에서는 병렬 TCAM을 기반으로 한 IP 주소 검색 구조에서 프리픽스를 신속하게 삭제하는 기법을 제안한다. 기존의 삭제 기법들은, 프리픽스의 순서 유지와 가용 메모리 공간의 연속성 유지를 위해 한 차례 이상의 메모리 이동을 필요로 하고 있다. 본 기법에서는 삭제 시 TCAM에서 실제 메모리를 이동하지 않고, SRAM으로 구현된 스택을 사용하여 삭제된 프리픽스의 주소를 이 스택에 저장한다. SRAM은 TCAM에 비해 접근시간이 매우 짧기 때문에, 제안된 기법이 신속한 갱신을 수행할 수 있다. 그리고 실제 사용되는 포워딩 테이블과 갱신 내용을 적용한 실험을 통해, 프리픽스 삽입과 삭제에 따른 메모리 접근 시간의 관점에서 제안된 기법의 성능을 평가한다. 또한 상대적으로 매우 작은 크기의 스택을 사용해도 좋은 성능을 나타내고 있음을 실험 결과를 통해 제시한다.

• ALGAE
• /
• 제24권2호
• /
• pp.85-91
• /
• 2009

The filamentous cyanobacterium Anabaena sp. Strain PCC 7120 produces a developmental patten of single hete- rocysts separated by approximately 10 vegetative cells. Heterocysts differentiate from vegetative cells and are spe- cialized for nitrogen fixation. The patS gene, which encodes a small peptide that inhibits heterocyst differentiation, is expressed in proheterocysts and plays a critical role in establishing the heterocyst pattem. Another key regulator of heterocyst development is the hetR gene. hetR mutants fail to produce heterocysts and extra copies of hetR on a plas- mid cause a multiple contiguous heterocyst phenotype. To elucidate the relationship between these two counter act- ing factors in the genetic regulatory pathway during heterocyst differentiation, the expression patterns of a patS-gfp and a hetR-gfp fusion were examined in a patS deletion and a hetR deletion strain. The results, in combination with the result from a hetR and patS double deletion strain, suggest patS and hetR are mutually antagonistic and the bal- ance between these two factors in tow different cell types (heterocysts and vegetative cells) may be critical during the decision making process on their cell fates.

• Asian-Australasian Journal of Animal Sciences
• /
• 제22권3호
• /
• pp.313-318
• /
• 2009

TIAF1 is a TGF-${\beta}$1-induced anti-apoptotic factor that plays a critical role in blocking TNF (tumor necrosis factor) cytotoxicity in mouse fibroblasts and participates in TGF-${\beta}$-mediated growth regulation. In this study, we obtained the full-length cDNA sequence of the porcine TIAF1 gene. Real-time PCR further revealed that the TIAF1 gene was expressed at the highest level in liver and kidney with prominent expressions detected in uterus, and lower levels detected in heart, spleen, lung, stomach, small intestine, skeletal muscle and fat of Large White pigs. Sequence analysis indicated that a 6 base-pair deletion mutation existed in the exon of the TIAF1 gene between Meishan and Large White pigs. This mutation induced deletion of Gln and Val amino acids. PCR-RFLP was used to detect the polymorphism in 394 pigs of a "Large White${\times}$Meishan" $F_{2}$ resource population and four purebred pig populations. The frequencies of the A allele (with a 6 bp deletion) were dominant in Chinese Meishan and Bamei pigs, and the frequencies of the B allele (no 6 bp deletion) were dominant in Large White and Landrace pigs. Association analyses revealed that the deletion mutation had highly significant associations (p<0.01) with meat marbling score of the thorax-waist longissimus dorsi (LD) muscle (MM1) and intramuscular fat percentage (IMF), and significant associations (p<0.05) with carcass length (CL). The results presented here supply evidence that the 6 bp deletion mutation in the TIAF1 gene affects porcine meat quality and provides useful information for further porcine breeding.

• Asian-Australasian Journal of Animal Sciences
• /
• 제16권12호
• /
• pp.1716-1721
• /
• 2003

Steroid hormones and their receptors play an important role in reproductive process. Estrogen is intimately involved with pregnancy and its function is mediated through the estrogen receptor which has been chosen as a candidate gene to study litter size in pigs. In this study, we report that two estrogen receptor variants, designated pER-1 and pER-2 were co-expressed in the uteri of normal cycling Lan-Yu pig (Sus vittatus; a small-ear miniature in Taiwan) with the pER-1 expression level appeared to be several times higher than that of pER-2. These receptor variants were isolated using reverse transcription-PCR from the pig uteri and their sequences were determined. The pER-1 and pER-2 sequences, which are homologous to those found in other mammalian estrogen receptors, encode putative proteins consisting of 574 and 486 amino acids, respectively. A deletion in exon I was identified in both sequences, with deletion lengths of 63 bp in pER-1 and 327 bp in pER-2. The deletion in pER-1 is internal to that in pER-2 and both deletions resulted in a truncation of the B domain, which confers the transactivating activity of estrogen receptor protein. This result describes the existence of estrogen receptor variants with a deletion in exon I and implies the possibility that physiological functioning of an estrogen receptor may not require the presence of an intact B domain.

• Journal of Microbiology and Biotechnology
• /
• 제30권5호
• /
• pp.662-667
• /
• 2020

Epidermal growth factor receptor (EGFR) mutations are not only genetic markers for diagnosis but also biomarkers of clinical-response against tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC). Among the EGFR mutations, the in-frame deletion mutation in EGFR exon 19 kinase domain (EGFR exon 19-del) is the most frequent mutation, accounting for about 45% of EGFR mutations in NSCLCs. Development of sensitive method for detecting the EGFR mutation is highly required to make a better screening for drug-response in the treatment of NSCLC patients. Here, we developed a fluorometric tandem gene amplification assay for sensitive detection of low-abundance EGFR exon 19-del mutant genomic DNA. The method consists of pre-amplification with PCR, thermal cycling of ligation by Taq ligase, and subsequent rolling circle amplification (RCA). PCR-amplified DNA from genomic DNA samples was used as splint DNA to conjugate both ends of linear padlock DNA, generating circular padlock DNA template for RCA. Long stretches of ssDNA harboring multiple copies of G-quadruplex structure was generated in RCA and detected by thioflavin T (ThT) fluorescence, which is specifically intercalated into the G-quadruplex, emitting strong fluorescence. Sensitivity of tandem gene amplification assay for detection of the EGFR exon 19-del from gDNA was as low as 3.6 pg, and mutant gDNA present in the pooled normal plasma was readily detected as low as 1% fraction. Hence, fluorometric detection of low-abundance EGFR exon 19 deletion mutation using tandem gene amplification may be applicable to clinical diagnosis of NSCLC patients with appropriate TKI treatment.

• ETRI Journal
• /
• 제34권4호
• /
• pp.637-640
• /
• 2012

The Davey-MacKay construction is a promising concatenated coding scheme involving an outer $2^k$-ary code and an inner code of rate k/n, for insertion-deletion-substitution channels. Recently, a lookup table (LUT)-based inner decoder for this coding scheme was proposed to reduce the computational complexity of the inner decoder, albeit at the expense of a slight degradation in word error rate (WER) performance. In this letter, we show that negligible deterioration in WER performance can be achieved with an LUT as small as $7{\cdot}2^{k+n-1}$, but no smaller, when the probability of receiving less than n-1 or greater than n+1 bits corresponding to one outer code symbol is at least an order of magnitude smaller than the WER when no LUT is used.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권13호
• /
• pp.5249-5252
• /
• 2014

Nogo protein, encoded by gene reticulon-4 (RTN4), includes three major isoforms by different splicing, named Nogo-A Nogo-B and Nogo-C. Nogo proteins play an important role in the apoptosis of cells, especially in tumor cells. RTN4 single nucleotide polymorphisms (SNPs) can influence the efficiency of transcription and translation thus being related with an individual's predisposition to cancer. The CAA insertion/deletion polymorphism (rs34917480) within RTN4 3'-UTR has been reported to be associated with many cancer types. In order to investigate the relationship between this polymorphism and susceptibility to non-small cell lung cancer (NSCLC) in the Chinese population, we conducted the present case-control study including 411 NSCLC patients and 471 unrelated healthy controls. The genotype distributions were significantly different between cases and controls (p=0.014). We found that the del allele could significantly increase NSCLC risk (ins/ins vs ins/del: p=0.007, OR 1.46, 95%CI=1.11-1.93; dominant model: p=0.004, OR 1.47, 95%CI=1.13-1.92 and allele model: p=0.008, OR 1.35, 95%CI=1.08-1.67). This association was stronger in participants over 60 years old, males and smokers. We therefore conclude that the CAA insertion/deletion polymorphism (rs34917480) contributes to non-small cell lung cancer risk in Chinese population. Age, sex and environmental exposure are also related to carcinogenic effects of rs34917480.

• Neonatal Medicine
• /
• 제16권1호
• /
• pp.76-80
• /
• 2009

저자들은 자궁 내 발육 지연으로 입원한 신새아가 요도하열, 잠복고환, 폐동맥판 협착이 동반되어 시행한 염색체 검사에서 불균형 전도로부터 재조합된 염색체이상의 결과로 8번 염색체 단완 결실과 장완 중복을 보인 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• 한국환경성돌연변이발암원학회지
• /
• 제19권1호
• /
• pp.7-13
• /
• 1999

The mouse lymphoma thymidine kinase (tk+/-) gene assay (MOLY) using L5178Y tk+/- mouse lymphoma cell line is one of the mammalian forward mutation assays. It is well known that MOLY has many advantages and more sensitive than the other mammalian forward mutation assays such as x-linked hyposanthine phosphoribosyltransferase (hprt) gene assay. The target gene of MOLY is a heterozygous tk+/- gene located in 11 chromosome of L5178Y tk+/- cell, so it is able to detect the wide range of genetic changes like point mutation, deletion, rearrangement, and mitotic recombination within tk gene or deletion of entire chromosome 11. MOLY has relatively short expression time (2-3 days) compared to 1 week of hprt gene assay. MOLY can also induce relatively high mutant frequency so a large number of events can be recorded. The bimodal distribution of colony size which may indicate gene mutation and chromosome breakage potential of chemicals according to mutation scale such as large normal-growing mutants and small slow-growing mutants can be observed in this assay. The statistical analysis of data can be performed using the MUTANT program developed by York Electronic Research in association with Hazelton as recommended by the UKEMS (United Kingdom Environmental Mutagen Society) guidelines. This report reviewed MOLY using the microtiter cloning technique (microwell assay).

• 대한골관절종양학회지
• /
• 제6권4호
• /
• pp.143-151
• /
• 2000

목적 : p53 종양억제 유전자는 사람의 암에서 변형이 가장 많이 발견되는 유전자로 유잉 육종에서 p53 유전자의 변형을 관찰하고자 하였다. 재료 및 방법 : 유잉육종 환자 35례의 파라핀 블록을 사용하였으며, 유전자의 결핍과 p53 유전자의 염기서열의 변형을 관찰하였다. 결과 : 정성적인 중합효소 연쇄반응을 이용한 p53의 4-9번까지의 유전자검사중 2례에서 동일성의 유전자 결핍이 관찰되었으며, exon 5-8의 유전자 중합효소 연쇄반응에서는 3례에서 missense 점돌연변이가 관찰되었다. 결론 : 이상의 결과로 p53은 유전적으로 적은 부분에서 유잉육종에 관여하는 것으로 관찰 되었다.