• 제목/요약/키워드: Nal

검색결과 144건 처리시간 0.026초

Effect of the Antimicrobial Peptide $\small{D}$-Nal-Pac-525 on the Growth of Streptococcus mutans and Its Biofilm Formation

  • Li, Huajun;Cheng, Jya-Wei;Yu, Hui-Yuan;Xin, Yi;Tang, Li;Ma, Yufang
    • Journal of Microbiology and Biotechnology
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    • 제23권8호
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    • pp.1070-1075
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    • 2013
  • Streptococcus mutans is the primary etiological agent of dental caries. The antimicrobial peptide $\small{D}$-Nal-Pac-525 was designed by replacing the tryptophans of the Trp-rich peptide Pac-525 with $\small{D}$-${\beta}$-naphthyalanines. To assess the effect of $\small{D}$-Nal-Pac-525 on cariogenic bacteria, the activity of $\small{D}$-Nal-Pac-525 on the growth of S. mutans and its biofilm formation were examined. $\small{D}$-Nal-Pac-525 showed robust antimicrobial activity against S. mutans (minimum inhibitory concentration of 4 ${\mu}g/ml$). Using scanning electron microscopy and transmission electron microscopy, it was shown that $\small{D}$-Nal-Pac-525 caused morphological changes and damaged the cell membrane of S. mutans. $\small{D}$-Nal-Pac-525 inhibited biofilm formation of S. mutans at 2 ${\mu}g/ml$. The results of this study suggest that $\small{D}$-Nal-Pac-525 has great potential for clinical application as a dental caries-preventing agent.

디지털 보청기에서의 NAL-NL1 기반 한국형 비선형 fitting formula 연구 (A Study of Korean Non-linear Fitting Formula based on NAL-NL1 for Digital Hearing Aids)

  • 김혜미;이상민
    • 대한의용생체공학회:의공학회지
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    • 제30권2호
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    • pp.169-178
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    • 2009
  • In this study, we suggest Korean nonlinear fitting formula (KNFF) to maximize speech intelligibility for digital hearing aids based on NAL-NL1 (NAL-nonlinear, version 1). KNFF was derived from the same procedure which is used for deriving NAL-NL1. KNFF consider the long-term average speech spectrum of Korean instead of English because the frequency characteristic of Korean is different from that of English. New insertion gains of KNFF were derived using the SII (speech intelligibility index) program provided by ANSI. In addition, the insertion gains were modified to maximize the intelligibility of high frequency words. To verify effect of the new fitting gain, we performed speech discrimination test (SDT) and preference test using the hearing loss simulator from NOISH. In the SDT, a word set as test material consists of 50 1-syllable word generally used in hearing clinic. As a result of the test, in case of moderate hearing loss with severe loss on high frequency, the SDT scores of KNFF was more improved about 3.2% than NAL-NLl and about 6% in case of the sever hearing loss. Finally we have obtained the result that it was the effective way to increase gain of mid-high frequency bands and to decrease gain of low frequency bands in order to maximize speech intelligibility of Korean.

EDI와 NAL 알고리듬을 기반으로 한 거리 가중치 비월주사 방식 알고리듬 (Weighted Distance De-interlacing Algorithm Based on EDI and NAL)

  • 이세영;구수일;정제창
    • 한국통신학회논문지
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    • 제33권9C호
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    • pp.704-711
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    • 2008
  • 본 논문은 효율적인 시각적 향상을 보여주는 새로운 비월 주사 방식 기법을 제안한다. 제안하는 알고리듬은 새로운 거리 가중치를 고려하며 이전에 개발되었던 EDI (Edge Dependent Interpolation) 알고리듬과 NAL (New Adaptive Linear interpolation) 알고리듬을 이용한다. 비월 주사 기법은 크게 2단계로 나된다. 우선 에지의 방향을 근접한 화소들의 정보를 이용하여 결정한다. 그리고 나서 잃어버린 화소 값들을 결정된 에지의 방향을 따라 보간 한다. 본 논문에서는 EDI 알고리듬을 통해 에지를 예측한 후에 NAL 알고리듬을 바탕으로 거리 가중치를 이용함으로써 잃어버린 화소들을 보간 한다. 실험 결과는 제안된 알고리듬이 기존의 알고리듬들보다 객관적 및 주관적인 평가에서 우수함을 입증한다.

A Practical RTP Packetization Scheme for SVC Video Transport over IP Networks

  • Seo, Kwang-Deok;Kim, Jin-Soo;Jung, Soon-Heung;Yoo, Jeong-Ju
    • ETRI Journal
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    • 제32권2호
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    • pp.281-291
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    • 2010
  • Scalable video coding (SVC) has been standardized as an extension of the H.264/AVC standard. This paper proposes a practical real-time transport protocol (RTP) packetization scheme to transport SVC video over IP networks. In combined scalability of SVC, a coded picture of a base or scalable enhancement layer is produced as one or more video layers consisting of network abstraction layer (NAL) units. The SVC NAL unit header contains a (DID, TID, QID) field to identify the association of each SVC NAL unit with its scalable enhancement layer without parsing the payload part of the SVC NAL unit. In this paper, we utilize the (DID, TID, QID) information to derive hierarchical spatio-temporal relationship of the SVC NAL units. Based on the derivation using the (DID, TID, QID) field, we propose a practical RTP packetization scheme for generating single RTP sessions in unicast and multicast transport of SVC video. The experimental results indicate that the proposed packetization scheme can be efficiently applied to transport SVC video over IP networks with little induced delay, jitter, and computational load.

Naloxone Postconditioning Alleviates Rat Myocardial Ischemia Reperfusion Injury by Inhibiting JNK Activity

  • Xia, Anzhou;Xue, Zhi;Wang, Wei;Zhang, Tan;Wei, Tiantian;Sha, Xingzhi;Ding, Yixun;Zhou, Weidong
    • The Korean Journal of Physiology and Pharmacology
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    • 제18권1호
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    • pp.67-72
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    • 2014
  • To investigate the alteration of c-Jun N-terminal kinase (JNK) activity after myocardial ischemia reperfusion injury (MIRI) and further explore the effect of naloxone postconditioning on MIRI. Forty male Sprague Dawley rats were randomly divided into five groups: sham operation (sham, n=8); ischemia reperfusion (IR, n=8); IR+naloxone 0.5 mg/kg (Nal L, n=8); IR+naloxone 1.0 mg/kg (Nal M, n=8); IR+naloxone 2.0 mg/kg (Nal H, n=8). Pathological changes of myocardial tissue were visualized by HE staining. The expression of p-JNK, and the apoptosis of cardiomyocytes were investigated with Western blotting and the TUNEL assay, respectively. Irregular arrangement and aberrant structure of myocardial fibers, cardiomyocytes with granular or vacuolar degeneration, and inflammatory cells infiltrating the myocardial interstitial regions characterized MIRI in the IR group. Signs of myocardial injury and inflammatory infiltration were less prominent in the Nal-treated groups. The expression of p-JNK in the sham group and in all Nal-treated groups was significantly lower than that in the IR group (p<0.01). The apoptosis index of cardiomyocytes in the IR group was significantly higher than in the sham group (p<0.01). The apoptosis indices of cardiomyocytes in all Nal-treated groups were significantly reduced to 55.4%, 26.2%, and 27.6%, respectively, of the IR group (p<0.01). This study revealed that Naloxone postconditioning before reperfusion inhibits p-JNK expression and decreases cell apoptosis, thus alleviating MIRI.

땅콩의 근류형성(根瘤形成)과 질소고정(窒素固定)에 대한 근류균(根瘤菌) 접종방법(接種方法)의 영향(影響) (Nodulation and N2 Fixation in Groundnut as Affected by Inoculation Method)

  • 김무기;소재돈;박건호;최대웅
    • 한국토양비료학회지
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    • 제25권1호
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    • pp.77-88
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    • 1992
  • 항생제 내성 변이균주 JB7 $nal^rspe^r$와 CB756 $str^rrif^r$을 이용하여 살균하지 않은 밭토양에서 접종방법이 근류균의 증식과 근류형성 및 질소고정에 미치는 영향을 조사하였다. JB7 $nal^rspe^r$균주(菌株)를 종자당 $10^2$에서 $10^8$세포수준으로 접종(接種)했을때 접종농도(接種濃度)의 증가와 함께 근류형성(根瘤形成)이 증가하였다. 접종방법별(接種方法別)로는 YMB배양 액체접종(液體接種)이 Peat slurry나 Peat입자(粒子) 접종(接種)보다 더 많은 근류(根瘤)를 형성(形成)했고, Peat slurry와 입자(粒子) 접종간(接種間)에는 차이가 없었다. 토양(土壤) g당 $10^3$ 세포(細胞)의 근류균(根瘤菌)을 함유(含有)하는 토양(土壤)에 JB7 $nal^rspe^r$와 CB756 $str^rrif^r$을 혼합(混合)하여 접종(接種)했을때 모든 근류(根瘤)가 접종균(接種菌)에 의하여 형성되었으며, JB7 $nal^rspe^r$균주(菌株)에 의한 근류점유율이 월등히 높았다. 품종간에 근류점유율의 차이는 없었다. 접종균류(接種菌株)는 근권에서 점진적으로 증식되었으며, JB7 $nal^rspe^r$가 더 큰 폭으로 증가되었다. 땅콩의 수량은 무접종구보다 접종구가 높았으나 질소처리구(窒素處理區)와 접종구간에는 차이가 없었다.

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Prolactin 유전자 발현과 분비에 미치는 naloxone의 영향 (Effect of Naloxone on the Estrogen-induced Prolactin Gene Expression and Secretion)

  • 김범수;김경진
    • 한국동물학회지
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    • 제34권3호
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    • pp.426-431
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    • 1991
  • The present study examines the effect of naloxone, mu-opioid receptor antagonist, on prolactin (PRL) gene expression and secretion induced by estradiol (I) treahent in vivo. Adult rats were ovariectomized (OW) and implanted with Silastic capsules containing either vehicle (oil) or E. Three days later, NAL (2 mg/kg BW) or saline urere injected 30 min prior to sacrifice. To examine PRL secretion in vitro, the pituitaries were incubated in the superfusion system for 3 hrs. Superfusates were collected at 10 min intenrals on ice and subjected to PRL radioimmunoassay. Endogenous release of PRL in OU( + I rats was signifcantlv higher than that in OVX rats (mean $\pm$ SE; 24.5 $\pm$ 3.1 vs 14.5 $\pm$ 2.9 ns/10 min). A single injection of NAL clearly inhibited PRL release in Nitro from pituitaries derived from OW + I rats, but not from OW group. PRL myNA was determined by RNA-blot hybridisation assay with nicktranslated PRL CDNA. E stimulated PRL mRNA about 3 fold over that shown in OW group. Treahent of NAL suppressed the I-stimulated PRL myNA in OVX + I group, but not in OVX group. These data clearly showed that the NAL-induced inhibition of PRL secretion was well correlated with changes in PRL mRNA level and this inhibitory process appears to be mediated in I-dependent manner.

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