• Journal of Microbiology
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• 제45권3호
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• pp.262-267
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• 2007

During a screening program, an actinomycete strain isolated from the Egyptian soil was investigated for its potential to show antimicrobial activity. The identification of this isolate was performed according to spore morphology and cell wall chemo-type, which suggested that this strain is a streptomycete. Further cultural, physiological characteristics and the analysis of the nucleotide sequence of the 16S rRNA gene (1480 bp) of this isolate indicated that this strain is identical to Streptomyces violaceusniger (accession number EF063682) and then designated S. violaceusniger strain HAL64. In its culture supernatant, this organism could produce one major compound strongly inhibits the growth of Gram-positive but the inhibition of Gram-negative indicator bacteria was lower. The antibiotic was separated by silica gel column chromatography and then purified on a sephadex LH-20 column and finally the purity was checked by HPLC. The chemical structure of the purified compound was determined using spectroscopic analyses (molecular formula of $C_{33}H_{32}N_{2}O_{10}$ and molecular weight of 617.21) and found to be identical to the kosinostatin, a quinocycline antibiotic which is known to be produced by Micromonspora sp. TP-A0468 (Igarashi et al., 2002) and to quinocycline B isolated from Streptomyces aureofaciens (Celmer et al., 1958). Although the antibiotic is known, the newly isolated strain was able to produce the antibiotic as a major product providing an important biotechnological downstream advantage.

• 한국멀티미디어학회논문지
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• 제10권6호
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• pp.737-744
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• 2007

This paper proposes the blind watermarking algorithm for digital video based on magnitude modulus subband in wavelet transform domain. After transforming each of frames into wavelet domain, the proposed algorithm divides LH, HL, and HH subbands of 2-level into $3{\times}3$ blocks and calculates average magnitude modulus of all blocks. Then the watermark bit is embedded into a target magnitude modulus comparing with an average magnitude modulus within a block. Experimental results were confirmed that the proposed algorithm has the good robustness against MPEG and frame attacks than the conventional algorithm.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2001년도 제41차 추계학술대회
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• pp.87-87
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• 2001

• Kyungpook Mathematical Journal
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• 제62권1호
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• pp.193-204
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• 2022

A subset S of V(G), where G is a simple undirected graph, is a hop dominating set if for each v ∈ V(G)＼S, there exists w ∈ S such that d_G(v, w) = 2 and it is a locating-hop set if N_G(v, 2) ∩ S ≠ N_G(v, 2) ∩ S for any two distinct vertices u, v ∈ V(G)＼S. A set S ⊆ V(G) is a locating-hop dominating set if it is both a locating-hop and a hop dominating set of G. The minimum cardinality of a locating-hop dominating set of G, denoted by 𝛄_lh(G), is called the locating-hop domination number of G. In this paper, we investigate some properties of this newly defined parameter. In particular, we characterize the locating-hop dominating sets in graphs under some binary operations.

• 한국발생생물학회지:발생과생식
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• 제25권3호
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• pp.133-143
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• 2021

In contrast to the human lutropin receptor (hLHR) and rat LHR (rLHR), very few naturally occurring mutants in other mammalian species have been identified. The present study aimed to delineate the mechanism of signal transduction by three constitutively activating mutants (designated M410T, L469R, and D590Y) and two inactivating mutants (D383N and Y546F) of the eel LHR, known to be naturally occurring in human LHR transmembrane domains. The mutants were constructed and measured cyclic adenosine monophosphate (cAMP) accumulation via homogeneous time-resolved fluorescence assays in Chinese hamster ovary (CHO)-K1 cells. The activating mutant cells expressing eel LHR-M410T, L469R, and D590Y exhibited a 4.0-, 19.1-, and 7.8-fold increase in basal cAMP response without agonist treatment, respectively. However, inactivating mutant cells expressing D417N and Y558F did not completely impaired signal transduction. Specifically, signal transduction in the cells expressing activating mutant L469R was not occurred with a further ligand stimulation, showing that the maximal response exhibited approximately 53% of those of wild type receptor. Our results suggested that the constitutively activating mutants of the eel LHR consistently occurred without agonist treatment. These results provide important information of LHR function in fish and regulation with regard to mutations of highly conserved amino acids in glycoprotein hormone receptors.

• 한국토양비료학회지
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• 제43권4호
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• pp.490-497
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• 2010

근권토양으로부터 고추역병균을 포함한 다양한 식물 병원성 곰팡이에 대하여 항균활성이 강한 세균을 분리하였다. 이 세균은 16S rRNA gene서열 분석 결과 Lysobacter enzymogens로 동정되었고 LE429로 명명 하였다. LE429는 chitinase, ${\beta}-1$, 3-glucanase, protease, gelatinase, lipase 및 항생물질과 같은 다양한 이차대사산물을 분비하였다. 항생물질은 diaon HP-20 및 sephadex LH-20 컬럼크로마토그래피 및 HPLC로 정제하여, GC-EI 및 GC-CI분석을 통하여 phenylacetic acid로 동정되었다. Field 실험에서 LE429의 고추 병해 억제 효과를 조사하기 위해 LE429배양액(CB), Neem oil 용액 (NO), LE429배양액과 Neem oil 용액을 섞은 혼합액(CB+NO), 그리고 대조구로서 물(CON)을 각각 고추에 처리하였다. 고추의 수량구성요소는 일반적으로 CB 처리구가 가장 높았고, CB+NO, CON 그리고 NO 순서로 나타났다. CB 처리구에서 병원성 곰팡이는 강하게 억제 되었지만, 몇몇 해충이 발견되었다. NO 처리구에서는 해충은 발견 되지 않았지만, 병원성 곰팡이가 발견 되었다. 하지만, CB+NO 처리구에서 병원성 곰팡이 및 해충이 전혀 발견 되지 않았다. 결론적으로, 2차 대 사산물을 생산하는 LE429와 Neem oil의 혼합액은 고추에 발생하는 병원성 곰팡이와 해충에 대한 좋은 생물학적 방제제가 될 수 있다고 사료된다.

• Clinical and Experimental Reproductive Medicine
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• 제42권2호
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• pp.62-66
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• 2015

Objective: To evaluate the effect of a gonadotropin-releasing hormone (GnRH) antagonist protocol using corifollitropin alfa in women undergoing assisted reproduction. Methods: Six hundred and eighty-six in vitro fertilization-embryo transfer (IVF)/ intracytoplasmic sperm injection (ICSI) cycles were analyzed. In 113 cycles, folliculogenesis was induced with corifollitropin alfa and recombinant follicle stimulating hormone (rFSH), and premature luteinizing hormone (LH) surges were prevented with a GnRH antagonist. In the control group (573 cycles), premature LH surges were prevented with GnRH agonist injection from the midluteal phase of the preceding cycle, and ovarian stimulation was started with rFSH. The treatment duration, quality of oocytes and embryos, number of embryo transfer (ET) cancelled cycles, risk of ovarian hyperstimulation syndrome (OHSS), and the chemical pregnancy rate were evaluated in the two ovarian stimulation protocols. Results: There were no significant differences in age and infertility factors between treatment groups. The treatment duration was shorter in the corifollitropin alfa group than in the control group. Although not statistically significant, the mean numbers of matured (86.8% vs. 85.1%) and fertilized oocytes (84.2% vs. 83.1%), good embryos (62.4% vs. 60.3%), and chemical pregnancy rates (47.2% vs. 46.8%) were slightly higher in the corifollitropin alfa group than in the control group. In contrast, rates of ET cancelled cycles and the OHSS risk were slightly lower in the corifollitropin alfa group (6.2% and 2.7%) than in the control group (8.2% and 3.5%), although these differences were also not statistically significant. Conclusion: Although no significant differences were observed, the use of corifollitropin alfa seems to offer some advantages to patients because of its short treatment duration, safety, lower ET cancellation rate and reduced risk of OHSS.

• 한국발생생물학회지:발생과생식
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• 제25권4호
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• pp.225-234
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• 2021

The present study aimed to investigate the mechanism of cell surface receptor loss by two constitutively activating mutants (designated L469R, and D590Y) and two inactivating mutants (D417N and Y558F) of the luteinizing hormone receptor (LHR) in the Japanese eel Anguilla japonica, known to naturally occur in human LHR transmembrane domains. We investigated cell surface receptor loss using an enzyme-linked immunosorbent assay in HEK 293 cells. The expression level of wild-type eel LHR was considered to be 100%, and the expression levels of L469R and D417N were 97% and 101%, respectively, whereas the expression levels of D590Y and Y558F slightly increased to approximately 110% and 106%, respectively. The constitutively activating mutants L469R and D590Y exhibited a decrease in cell surface loss in a manner similar to that of wild-type eel LHR. The rates of loss of cell surface agonist-receptor complexes were observed to be very rapid (2.6-6.2 min) in both the wild-type eel LHR and activating mutants. However, cell surface receptor loss in the cells expressing inactivating mutants D417N and Y558F was slightly observed in the cells expressing inactivating mutants D417N and Y558F, despite treatment with a high concentration of agonist. These results provide important information on LHR function in fish and the regulation of mutations of highly conserved amino acids in glycoprotein hormone receptors.

• 산업진흥연구
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• 제3권2호
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• pp.1-8
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• 2018

본 연구에서는 탄화수소 개질을 위한 예비 개질기에서 에탄의 반응 메커니즘과 이에 적합한 반응속도식에 대한 연구를 수행하였다. 반응 mechanism 분석을 통해 ethane의 개질 반응 중 (CO2+H2,C2H6+H2,C2H6+H2O)3개의 반응이 진행되는 것을 확인할 수 있었으며, 각각의 반응 속도 (CO2+H2($r=3.42{\times}10-5molgcat.-1\;s-1$), C2H6+H2($r=3.18{\times}10-5mol\;gcat.-1s-1$), C2H6+H2O($r=1.84{\times}10-5mol\;gcat.-1s-1$)) 를 구하였다. 이를 통해 C2H6+H2O반응이 rate determining step (RDS)임을 확인하고, Langmuir-Hinshelwood model (L-H model)을 통해 이 반응의 반응식을 r=kS*(KAKBPC2H6PH2O)/(1+KAPC2H6+KBPH2O)2 (KA=2.052,KB=6.384,$kS=0.189{\times}10-2$)로 나타낼 수 있었다. 이렇게 얻어진 반응식은 반응 메커니즘을 고려하지 않고 유도된 power rate law와 비교하였으며, power rate law는 좁은 농도 변화 영역 (ethane 약 2.5-4%, water 약 60-75%)에서는 비교적 유사한 fitting이 이루어졌지만, 넓은 농도 변화영역에서는 반응 mechanism을 토대로 얻은 L-H model 반응식이 실험값과 더 유사한 값을 보이는 것을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1775-1779
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• 2005

Seventy-two crossbred gilts of approximately 33 kg initial weight were used in this study. The gilts were randomly assigned into three groups. The three dietary treatments were basal diet only (control group), basal diet+10 mg/kg lead, and basal diet+10 mg/kg lead+0.5% particulate montmorillonite (PM). The results showed that the addition of lead to the diet decreased significantly the body weight and feed efficiency, but PM could restore body weight and feed efficiency of gilts compared to the Pb exposure group. There were no significant differences in weights of ovaries and uteri with addition of either lead or PM to the diet. Supplementing the lead in the diet of gilts also significantly increased the concentration of lead in blood, decreased circulating lutenizing hormone (LH) and estradiol (E$_2$) levels in serum, the addition of PM to the diet effectively adsorbed and lowered lead concentration in the blood. These data suggested that lead disrupts the signals between the hypothalamus and pituitary gland in gilts, and possibly suppressed the secretion of relative growth hormone and sex hormone. On the other hand, PM may ameliorate Pb toxicity in pigs.