• Biomolecules & Therapeutics
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• 제2권2호
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• pp.155-160
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• 1994

Human immunodeficiency virus type 1 (HIV-1) protease is essential for the replication of the virus and it is therefore an attractive target for antiviral drugs of HIV-1. Several dipeptide isosteres containing 2-isoxazoline or $\alpha$-hydroxy ketomethylene have been synthesized and their inhibitory effects on the HIV-1 protease examined. The enzymatically active HIV-1 protease was purified to homogeniety from E. coli transformed with a recombinant plasmid (pMAL-pro) containing the entire gene encoding the protease. The purified protease had the substrate specificity with Km value of 9.8$\mu$M when an undecapeptide His-Lys-Ala-Arg-Val-Leu-(p-nitro)Phe-Glu-Ala-Nle-Ser-amide was used as a substrate, and the products from the substrate after specific cleavage by HIV-1 protease were analyzed by HPLC. The synthetic compounds containing dipeptide isosteres showed specific inhibitory effects while a dipeptide isostere containing an isoxazoline ring inhibited the HIV-1 protease competitively with Ki value of 500 $\mu$M. Even if the inhibition effects of HIV-1 protease were not very high, these novel dipeptide isosteres can be used as key structural moieties for developing specific inhibitors of HIV-1 protease.

• 대한수의학회지
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• 제59권3호
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• pp.151-155
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• 2019

Equine influenza (EI) is the main cause of respiratory illness in equines across the globe and is caused by equine influenza A virus (EIV-A), which has impacted the equine industry internationally because of the marginal mortality and high morbidity. In the present study, the immune responses after equine influenza vaccination were evaluated in 4,144 horses in Korea using the hemagglutination inhibition (HI) assay. The equine influenza virus (EIV), A/equine/South Africa/4/03 (H3N8), was used as the antigen in the HI assay. The mean seropositive rates were 89.2% (97.4% in 2016, 77.6% in 2017, and 92.4% in 2018). This paper highlights the advances in understanding the effects of vaccines and control strategies for mitigating the emerging menace by EIV.

• Natural Product Sciences
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• 제5권1호
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• pp.33-38
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• 1999

Ethanolic extracts of different parts of 10 local traditional vegetables (ulam) (Amaranthus gangeticus, Jussiaea linifolia, Eugenia polyantha, Trapa incisa, Trichosanthes anquina, Mangifera indica, Pachyrrhirus erosus, Barringtonia mcarostachya, Carica papaya, and Coleus tuberosus) were screened for in vitro antitumor promoting activity using the inhibition test of Epstein-Barr virus (EBV) activation in Raji cells induced by phorbol 12-myristate 13-acetate and sodium-n-butyrate. All the extracts were found to have strong inhibition activity toward EBV-activation, except for leaf extract of T. anquina. The extracts were non-cytotoxic to the Raji cells except for the extracts of A. gangeticus (leaves), B. macrostachya (leaves), E. polyantha (young leaves), and J. linifolia (leaves) where the viability of the cells were decreased significantly.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3232-3238
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• 2014

Mollugin has been reported to have various biological activities including antineoplastic, antitumor, antiviral against the hepatitis B virus, anti-aging and antimutagenic activities. An effective and concise synthesis of mollugin in two steps including kinetic control from the cheap starting material 1,4-naphthoquinone has been introduced, and mollugin derivatives thus prepared are screened for their inhibition ability against the hepatitis C virus (HCV) and the dihydrobenzochromene structure might be an additional anti-HCV agent as a new leading compound.

• 대한화학회지
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• 제67권4호
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• pp.226-235
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• 2023

Chikungunya fever has a high morbidity rate in humans and is caused by chikungunya virus. There are no treatments available until now for this particular viral disease. The present study was carried out by selecting 19 flavonoids, which are available naturally in fruits, vegetables, tea, red wine and medicinal plants. The molecular docking of selected 19 flavonoids was carried out against the Chikungunya virus capsid protein using the Autodock4.2 software. Binding affinity analysis based on the Intermolecular interactions such as Hydrogen bonding and hydrophobic interactions and drug-likeness properties for all the 19 flavonoids have been carried out and it is found that the top four molecules are Chrysin, Fisetin, Naringenin and Biochanin A as they fit to the chikungunya protein and have binding energy of -8.09, -8.01, -7.6, and 7.3 kcal/mol respectively. This result opens up the possibility of applying these compounds in the inhibition of chikungunya viral protein.

• BMB Reports
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• 제28권6호
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• pp.538-545
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• 1995

When DNA replication of simian virus 40 (SV40) is initiated on the replication origin, the regions containing the initiation sites of DNA primase, which participates in the transient RNA primer synthesis for formation of Okazaki fragments in the lagging strand, were chosen as the target sites of antisense RNA for studies of the inhibition of SV40 DNA replication. Four recombinant transcription vectors, pUC-PrI, pUC-PrII, pGEM-PrBS, and pGEM-PrSN, coding antisense RNA, were constructed. Four antisense RNAs (named as I, II, BS, and SN) having the size of 18, 19,58, and 123 nts, respectively, were made from the transcription vectors by in vitro transcription. And then, antisense RNA in the concentration of 2${\mu}m$ were added to COS cells transfected with pATSV-W which is a recombinant plasmid containing the SV40 origin of replication. The inhibitory extent of DNA replication was measured by DpnI resistance and was confirmed by measurement of transient RNA primer synthesis. The result shows that six combinations of antisense RNA (I, II, BS, SN, I+SN, and BS+SN) lead to the inhibition of SV40 DNA replication by up to 85%.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
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• pp.56.2-56.2
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• 2007

See Full Text

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.264.1-264.1
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• 2003

In order to search for the anti-HIV agents from natural products, Eighty MeOH extracts of medicinal plants were applied to a syncytia formation inhibition assay which is based on the interaction between the HIV-1 envelope glycoprotein gp120/gp41 and the cellular membrane protein CD4 of T lymphocytes. Among them, Ailanthus altissima showed a potent virus-cell fusion inhibitory activity. (omitted)

• 대한수의학회지
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• 제31권2호
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• pp.189-194
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• 1991

Getah virus is known as a causative agent of recognized febrile illness of horses characterized by fever, rash and edema. A serological survey indicated that hemagglutination inhibition antibody against Getah virus was detected in 34% of 464 racehorses from Korean Horse Affairs Association and 57% of 262 ponies from Cheju island, respectively. Several field strains of Getah virus isolated were from the racehorse that have been shown fever and febrile signs in 1989. The field isolates produced cytopathic effect in Vero, MA-104, BHK-21 cell cultures. Especially, they multiplied to the highest titer($10^6TCID_{50}/0.1ml$) in Vero cell cultures. When day-old mice were inoculated with field isolates by the intracerebral route, they showed a typical paralysis sign and died within seven days after inoculation. The guinea pig exhibited skin rash and edema, and died with neural signs after inoculation with the field isolates. In the cross neutralization test and indirect immunofuorescent assay, the field isolates were proved to be closely related to the Sakai strain of Getah virus antigenically.

• Biomolecules & Therapeutics
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• 제1권1호
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• pp.98-102
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• 1993

The therapeutic effectiveness of adenine arabinoside(tora-A) and its conjugate of prednisone(BR-8702-AP) was compared in Herpes simplex Virus Type 1 (HSV-1) infected BALB/C mice. The BALB/C mouse was infected with HSV-1(700 PFU/mouse) intranasally. Among mice infected intranasally with virus, a mortality rate of 100% was observed. On the oral administration of non-toxic doses of ara-A or BR-8702-AP(125 mg /kg/day) for 5 consecutive days 2 hours after virus infection, the tora-A was highly effective in reducing mortality to 0% (P<0.001) and BR-8702-AP was also effective in reducing mortality to 15% (P<0.01). In this model infection, the virus was first replicated in the lung and transmitted to the brain. Both arts-A and BR-8702-AP did not inhibit the viral replication in the lung, but they inhibited the viral transmission to the brain. However, the BR-8702-AP was less effective than the aria-A to prevent transmission of virus to brain. Therefore, the reduced mortality due to tora-A or BR-8702-AP therapy was associated with inhibition of viral transmission to brain.