• Applied Biological Chemistry
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• 제38권6호
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• pp.522-527
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• 1995

흑조위축병 바이러스(RBSDV)에 대한 antiviral agent를 개발하기위하여 RBSDV 게놈 조각 3번을 절단하는 망치머리형 구조의 라이보자임을 설계하였다. 라이보자임과 기질의 oligonucleotides는 DNA 합성기로 합성 후 서로 합치고, pBluescript KS(+)에 삽입하였다. 라이보자임과 기질 RNA는 $T_3$ RNA polymerase로 기내 전사하여 각각 193과 183 nucleotide의 RNA를 얻었다. 기질 RNA는 라이보자임 RNA에 의해 $55^{\circ}C$에서 2개의 조각으로 절단되었으나 $37^{\circ}C$에서는 절단되지 않았다. 또한 RBSDV의 3번 조각 RNA도 동일한 라이보자임에 의해 절단되었다. 이러한 결과로 합성된 헤머해드 라이보자임은 기내 절단 능력을 가지며 형질전환 식물체에서 antiviral agent로 이용될 수 있을 것이다.

• 한국임상약학회지
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• 제32권3호
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• pp.191-203
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• 2022

Background: Direct-acting antivirals are recommended for the treatment of chronic hepatitis C virus in Korea. However, evaluation of direct-acting antiviral regimens in a real-world setting is limited. The aims of this study were to investigate the effectiveness and safety of direct-acting antiviral treatment in Korean patients infected with chronic hepatitis C virus genotype 1b or 2 at a tertiary care hospital. Methods: This was a retrospective study conducted with patient data obtained between August 2015 and August 2019 at Jeonbuk National University Hospital. The primary effectiveness endpoint was sustained virological response 12 weeks post-treatment (SVR12) via intention-to-treat (ITT) and modified intention-to-treat (mITT) analyses. Results: Of the 270 patients, 47.0% were infected with genotype 1b and 53.0% with genotype 2. ITT analysis revealed that SVR12 was achieved in 78.9% of all patients, 77.2% in genotype 1b patients, and 80.4% in genotype 2 patients. Of the 21.1% of all patients who did not achieve SVR12, the majority of treatment failures were non-virologic failures (19.7%). mITT analysis revealed that SVR12 was achieved in 98.2% of all patients, 98.0% in genotype 1b patients, and 98.3% in genotype 2 patients. Almost half of all patients experienced one or more adverse events (43.3%), leading to 2.6% discontinuing scheduled treatment. The most common adverse event was anemia. Conclusions: Direct-acting antiviral-based treatment regimens showed high effectiveness and safety. Non-virological factors, such as premature treatment discontinuation due to adverse events or loss of follow-up, were the major disruptors in achieving SVR12.

• Molecules and Cells
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• 제27권6호
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• pp.689-695
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• 2009

Chemically synthesized small interfering RNAs (siRNAs) can specifically knock-down expression of target genes via RNA interference (RNAi) pathway. To date, the length of synthetic siRNA duplex has been strictly maintained less than 30 bp, because an early study suggested that double-stranded RNAs (dsRNAs) longer than 30 bp could not trigger specific gene silencing due to the induction of non-specific antiviral interferon responses. Contrary to the current belief, here we show that synthetic dsRNA as long as 38 bp can result in specific target gene silencing without non-specific antiviral responses. Using this longer duplex structure, we have generated dsRNAs, which can simultaneously knock-down expression of two target genes (termed as dual-target siRNAs or dsiRNAs). Our results thus demonstrate the structural flexibility of gene silencing siRNAs, and provide a starting point to construct multifunctional RNA structures. The dsiRNAs could be utilized to develop a novel therapeutic gene silencing strategy against diseases with multiple gene alternations such as viral infection and cancer.

• 약학회지
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• 제39권6호
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• pp.622-630
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• 1995

Inoculation of Friend anemia virus, which was a Kind of retro virus such as HIV, results splenomegaly, anemia, the increase of WBC counts and reverse transcriptase activity in serum. These results were due to the inhibition of the differentiation of erythroid progenitor cell by the FVA at the spleen. Using these as index of antiviral effects, we pursued the establishment of in vivo screening method for the new anti-ADS drugs. Among zidovudine, didanosine and zalcitabine, which were already approved as anti-AIDS drugs, treatment of zidovudine for 18 days in BALB/c mice inoculated with Friend anemia virus resulted the most potent inhibitory effects on the splenomegaly, the increase of WBC counts and reverse transcriptase activity, but did not recovered the anemia due to the tomcity of zidovudhie itself on the bone marrow. The antiviral effects of zidovudine was reduced in case of zidovudine treatment 7 days after Friend anemia virus inoculation. These results suggested that the sooner treatment of zidovudine would be better improved when the virus was inoculated. Human recombinant interferon itself .alpha. did not showed the antiviral activity against Friend anemia virus and did not also affected the antiviral activity of zidovudine. These results suggested that Friend anemia virus would be used as a tool in vivo screening method for the Lobster of reverse transcriptase.

• 약학회지
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• 제48권1호
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• pp.88-92
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• 2004

In this study; a series of 2',4'-doubly branched carbocyclic nucleosides (8,9,10) were synthesized from simple acyclic ketone derivative as starting material. The installation of the 4'-quaternary carbon needed was carried out using a 〔3,3〕-sigmatropic rearrangement. In addition, the introduction of a methyl group in the 2'-position was accomplished by Grig-nard reaction. Bis-vinyl was successfully cyclized using a Grubbs' catalyst II. The natural bases (adenine, cytosine, uracil) were efficiently coupled with the use of a Pd(0) catalyst. Although all the synthesized compounds were assayed against several viruses, only cytosine analogue 9 showed weak antiviral viral activity (EC$_{50}$=45.4 $\mu$M) against CoxB3 virus.s.

• 한국축산식품학회지
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• 제30권2호
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• pp.345-350
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• 2010

Various extracts from 30 medicinal plants were evaluated for their antiviral activity against influenza virus A/Puerto Rico/8/34 (H1N1) and cytotoxicity in MDCK cell culture. The plant material (30 g) was extracted with methanol (300 mL) at room temperature for 24 h, after which the methanolic extracts were filtered, evaporated, and subsequently lyophilized. Evaluation of the potential antiviral activity was conducted by a viral replication inhibition test. Among these medicinal plants, Tussilago farfara, Brassica juncea, Prunus armeniaca, Astragalus membranaceus, Patrinia villosa, and Citrus unshiu showed marked antiviral activity against influenza virus A/H1N1 at concentrations ranging from 0.15625 mg/mL to 1.25 mg/mL, 0.3125 mg/mL to 10 mg/mL, 5 mg/mL to 10 mg/mL, 0.625 mg/mL to 10 mg/mL, 0.625 mg/mL to 10 mg/mL, and 0.3125 mg/mL to 5 mg/mL, respectively. The extracts of Tussilago farfara showed cytotoxicity at concentrations greater than 2.5 mg/mL, whereas the other five main extracts showed no cytotoxicity at concentrations of 10 mg/mL. Taken together, the present results indicated that methanolic extracts of the six main plants might be useful for the treatment of influenza virus H1N1.

• Journal of Ginseng Research
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• 제47권2호
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• pp.183-192
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• 2023

Viral infections are known as one of the major factors causing death. Ginseng is a medicinal plant that demonstrated a wide range of antiviral potential, and saponins are the major bioactive ingredients in the genus Panax with vast therapeutic potential. Studies focusing on the antiviral activity of the genus Panax plant-derived agents (extracts and saponins) and their mechanisms were identified and summarized, including contributions mainly from January 2016 until January 2022. P. ginseng, P. notoginseng, and P. quinquefolius were included in the review as valuable medicinal herbs against infections with 14 types of viruses. Reports from 9 extracts and 12 bioactive saponins were included, with 6 types of protopanaxadiol (PPD) ginsenosides and 6 types of protopanaxatriol (PPT) ginsenosides. The mechanisms mainly involved the inhibition of viral attachment and replication, the modulation of immune response by regulating signaling pathways, including the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway, cystathionine γ-lyase (CSE)/hydrogen sulfide (H₂S) pathway, phosphoinositide-dependent kinase-1 (PDK1)/ protein kinase B (Akt) signaling pathway, c-Jun N-terminal kinase (JNK)/activator protein-1 (AP-1) pathway, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. This review includes detailed information about the mentioned antiviral effects of the genus Panax extracts and saponins in vitro and in vivo, and in human clinical trials, which provides a scientific basis for ginseng as an adjunctive therapeutic drug or nutraceutical.

• 한국식물병리학회지
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• 제13권1호
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• pp.63-68
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• 1997

In the screening of antiviral materials produced by actinomycetes, an isolate named B25 was fond to produce an antibiotic substance ASA, which showed a strong inhibitory activity against tobacco mosaic virus (TMV) infection. ASA was purified from culture broth of B25 by silica gel column chromatography, preparative TLC, and reversed phase HPLC. Also MS, IR, UV spectrum, and melting point of ASA were determined and analysed. ASA was white powder soluble in dimethyl sulfoxide, chloroform, and ethyl acetate, having absorption peaks at 223 and 328 nm in UV-VIS spectrum, and had a molecular weight of 548. ASA showed strong inhibitory effect on TMV infection when it was applied as a mixture of TMV to the upper surface of leaves of a local lesion host (Nicotiana tabacum c. Xanthi-nc). It also showed antimicrobial effect against yeast and some phytopathogenic fungi.

• Archives of Pharmacal Research
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• 제23권4호
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• pp.302-309
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• 2000

Based on (-)-neplanocin A with the 5'-hydroxyl substituted with fluoro, azido, or amino group, the corresponding xylo- and arabino derivatives were synthesized from D-ribose using the Mit-sunobu reaction as a key step. None of the final nucleosides did show either significant antiviral activities or cytotoxicities.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1812-1816
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• 2004

The stereoselective synthesis 4′,6′-dually branched carbocyclic nucleosides was accomplished in this study. The introduction of a methyl group in the 6′$({\alpha})$-position was accomplished by Felkin-Anh controlled alkylation. The construction of the required 4′$({\alpha})$-quaternary carbon was carried out using a [3,3]-sigmatropic rearrangement. Bis-vinyl 6 was successfully cyclized using a Grubbs' catalyst II. The natural bases (adenine, cytosine) were efficiently coupled using a Pd(0) catalyst. When the synthesized compounds were examined for their activity against several viruses such as the HIV-1, HSV-1, HSV-2 and HCMV, the cytosine analogue 13 exhibited good antiviral activity against the HCMV.