• Molecules and Cells
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• 제28권1호
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• pp.49-55
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• 2009

Hepatitis delta virus (HDV) infection causes fulminant hepatitis and liver cirrhosis. To elucidate the molecular mechanism of HDV pathogenesis, we examined the effects of HDV viral proteins, the small hepatitis delta antigen (SHDAg) and the large hepatitis delta antigen (LHDAg), on $NF-{\kappa}B$ signaling pathway. In this study, we demonstrated that $TNF-{\alpha}-induced$ $NF-{\kappa}B$ transcriptional activation was increased by LHDAg but not by SHDAg in both HEK293 and Huh7 cells. Furthermore, LHDAg promoted TRAF2-induced $NF-{\kappa}B$ activation. Using coimmunoprecipitation assays, we demonstrated that both SHDAg and LHDAg interacted with TRAF2 protein. We showed that isoprenylation of LHDAg was not required for the increase of $NF-{\kappa}B$ activity. We further showed that only LHDAg but not SHDAg increased the $TNF-{\alpha}-mediated$ nuclear translocation of p65. This was accomplished by activation of $I{\kappa}B_{\alpha}$ degradation by LHDAg. Finally, we demonstrated that LHDAg augmented the COX-2 expression level in Huh7 cells. These data suggest that LHDAg modulates $NF-{\kappa}B$ signaling pathway and may contribute to HDV pathogenesis.

• Journal of Nutrition and Health
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• 제30권4호
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• pp.442-450
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• 1997

Conjugated dienoic derivatives of linoleic acid(CLA) are a mixture of positional and geometric isomers of linoleic acid(LA). We previously found that CLA changes the fatty acid profile in chicken eggs and serum by decreasing monounsaturated fatty acids. Studies were conducted to explore the effects of CLA on fatty acid composition. Rabbits were fed a semisynthetic diet with or without CLA(0.5g CLA/rabbit/day) for 22 weeks. Compared to the control, rabbits fed CLA had significantly lower monounsaturated fatty acid levels(palmitoleic acid Cl6 : 1 by 50% and oleic acid Cl8 : 1, by 20%) in plasma lipids. We found similar differences in fatty acid composition in the liver and the aorta. The inhibitory effect of CLA on $\Delta$9 desaturation was confirmed in a human hepatoma cell line, Hep G2. CLA significantly decreased $\Delta$9 desaturation in 4-5 hours as shown by an increase in the ratio of Cl6 : 0 to C 16 1, This is apparently due to a decrease in $\Delta$9 desaturase(stearoyl-CoA desaturase, SCD) activity ; it was decreased more than 50%. These results, along with our previous findings, indicate that CLA is an inhibitor of $\Delta$9 desaturase in the liver.

• 한국식품과학회지
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• 제31권1호
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• pp.164-170
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• 1999

저장 중 쌀의 수분이동에 따른 균열현상을 구명하고 균열을 발생시키는 임계조건을 산출하여 이를 토대로 쌀의 균열을 방지할 수 있는 저장조건을 확립하였다. 쌀의 평형상대습도와 노출된 환경의 상대습도의 차이$({\Delta}ERH)$가 적을 때는 균열이 발생하지 않은 반면, 그 차이가 임계치보다 클 때는 균열이 발생하였으며 균열의 발생정도는 쌀의 평형상대습도와 환경의 상대습도의 차이가 클수록 심하게 나타났다. 탈습환경 하에서는 불규칙한 형상의 균열이 쌀알의 외부에 발생하였으며 흡습환경 하에는 규칙적인 형상의 균열이 쌀알의 내부에 축방향과 수직방향으로 방사상으로 발생하였다. 노출시간별 균열발생 패턴을 Weibull함수에 의거하여 해석한 결과, ${\Delta}ERH$가 클수록 균열속도상수가 증가하였다. 동할미 발생률은 In$({\Delta}ERH)$에 따라 직선적으로 증가하였으며, 임계 균열발생 상대 습도차(critical crack-inducing ${\Delta}ERH$)는 탈습시 $11.3{\sim}16.4%$, 흡습시 $10.8{\sim}17.1%$의 값을 보였다. 실험결과를 토대로 수분함량 및 수분활성도 별 쌀의 안전저장 상대습도를 나타내는 diagram을 제시하였다.

• Journal of Ginseng Research
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• 제43권2호
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• pp.218-225
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• 2019

Background: Streptococcus pneumoniae, more than 90 serotypes of which exist, is recognized as an etiologic agent of pneumonia, meningitis, and sepsis associated with significant morbidity and mortality worldwide. Immunization with a pneumococcal pep27 mutant (${{\Delta}}pep27$) has been shown to confer comprehensive, long-term protection against even nontypeable strains. However, ${{\Delta}}pep27$ is effective as a vaccine only after at least three rounds of immunization. Therefore, treatments capable of enhancing the efficiency of ${{\Delta}}pep27$ immunization should be identified without delay. Panax ginseng Mayer has already been shown to have pharmacological and antioxidant effects. Here, the ability of Korean Red Ginseng (KRG) to enhance the efficacy of ${{\Delta}}pep27$ immunization was investigated. Methods: Mice were treated with KRG and immunized with ${{\Delta}}pep27$ before infection with the pathogenic S. pneumoniae strain D39. Total reactive oxygen species production was measured using lung homogenates, and inducible nitric oxide (NO) synthase and antiapoptotic protein expression was determined by immunoblotting. The phagocytic activity of peritoneal macrophages was also tested after KRG treatment. Results: Compared with the other treatments, KRG significantly increased survival rate after lethal challenge and resulted in faster bacterial clearance via increased phagocytosis. Moreover, KRG enhanced ${{\Delta}}pep27$ vaccine efficacy by inhibiting reactive oxygen species production, reducing extracellular signal-regulated kinase apoptosis signaling and inflammation. Conclusion: Taken together, our results suggest that KRG reduces the time required for immunization with the ${{\Delta}}pep27$ vaccine by enhancing its efficacy.

• Environmental Analysis Health and Toxicology
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• 제1권1호
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• pp.61-70
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• 1986

The effect of polychlorinated biphenyls (PCB), phenol and biphenyl on the body, liver and kidney weights, and the activity of $\delta$-aminolevulinic acid dehydratase (ALAD), and the contents of microsomal cytochrome P-450, and hematocrit, TBAvalue. PCB (200 mg/kg), phenol (200 mg/kg), biphenyl (200 mg/kg), and biphenyl (100 mg/kg) added phenol (100 mg/kg) was treated orally to Sprague-Dawley rats for 3 days. In all treated groups, the body weights were decreased, while the weights of liver and kidney were increased in comparison with that of control group. The activity of $\delta$-ALAD was increased and hematocrit was decreased in PCB treated group, on the contrary biphenyl treated group was appeared opposite direction. The contents of microsomal cytochrome P-450 and concentration of protein were increased in all treated group. In biphenyl treated group and phenol treated group, TBA value was increased in both groups.

• 약학회지
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• 제46권1호
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• pp.69-74
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• 2002

The effects of genistein on murine thymocytes for inducing apoptotic cell death and phagocytic activity of peritoneal macrophage were studied in vitro. Addition of genistein (10 and 50$\mu$M) to cultured thymocytes from BALB/c mice definitely promoted DNA fragmentation. Also, cytofluorometric analysis of these cells demonstrated a reduction in mitochondrial transmembrane potential ($\Delta$Ψm). But, repeated administration of genistein (1 mg/mouse/day) to mice for 7 days did not cause any detectable DNA fragmentation. Genistein decreased lucigenin chemiluminescence and engulfment of fluorescein-conjugated E. coli particles in peritoneal macrophage. These results suggest that genistein induce an apoptosis of thymocyte via reduction in $\Delta$Ψm and decrease phagocytic activity of peritoneal macrophage in vitro.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.261-269
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• 2012

The cyclic dimers of enkephalin were isolated as minor components during the solution synthesis of the corresponding cyclic monomers. The ratio of cyclic dimer to monomer was approximately 1:4 from the percent of yields. In the receptor binding assay of two cyclic dimmers, ($Tyr_2-C[D-Glu-Phe-gPhe]_2$ 6, $Tyr_2-C[D-Asp-Phe-gPhe-rLeu]_2$ 8), both analogs exhibited the high preference for ${\delta}$ receptor compared to monocyclic counterparts. In the nociceptive activity, both showed about 5 times less potent than the cyclic monomers. The repeated synthesis of 14-membered cyclic analog, Tyr-C[D-Glu-Phe-gPhe-D-rLeu] 14, which was known as having three distinct cis-trans isomers, gave rise to apparently different conformational analog arousing only trans isomer. In the receptor binding assay, it showed tremendously high selectivity toward ${\mu}$ receptor $({\delta}/{\mu}=160)$.

• 한국대기환경학회지
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• 제24권4호
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• pp.393-403
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• 2008

In an effort to estimate secondary $PM_{10}$ concentrations and their diurnal variations at different photochemical activities, $PM_{10}$, CO, and $O_3$ concentrations obtained from the ambient air quality network located in Seoul are analyzed for the period from 2000 to 2005. In order to classify the photochemical activities on a daily basis, measured ${\Delta}O_{3,\;max-min}$ (maximum $O_3$-minimum $O_3$) and ${\int}(hv)dt$ which represents accumulated daily insolation, were used to classify each day into three regimes: 1) low photochemical reactivity; ${\Delta}O_{3,\;max-min}\;{\leq}\;40\;ppb$, and ${\int}(hv)dt\;{\leq}\;4000\;W/m^2$, 2) moderate photochemical reactivity; $40\;ppb\;<\;{\Delta}O_{3,\;max-min}\;{\leq}\;60\;ppb$, and $4000\;{\leq}\;{\int}(hv)de\;{\leq}\;6000\;W/m^2$, and 3) high photochemical reactivity; ${\Delta}O_{3,\;max-min}\;>\;60\;ppb$, and ${\int}(hv)dt\;{\geq}\;6000\;W/m^2$. The ratio of ($PM_{10}$/CO) obtained at low photochemical activity regime was used as an index of tracer for the estimation of secondary $PM_{10}$ at higher photochemical activity regimes. The results show that the estimated secondary $PM_{10}$ concentrations for moderate and high photochemical regimes are found to be 18.8% ($10.9\;{\mu}g/m^3$), and 35.0% ($26.2\;{\mu}g/m^3$), respectively. Diurnal variation of secondary $PM_{10}$ for the moderate photochemical regime shows weak but noticeable patterns. However, the highly activated photochemical regime shows strong diurnal variations of secondary $PM_{10}$ concentrations with the maximum value of $35.1\;{\mu}g/m^3$ at 1300LST.

• Restorative Dentistry and Endodontics
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• 제21권2호
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• pp.505-516
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• 1996

The effects of application of dentin desensitizer containing glutaraldehyde (Gluma Desensitizer) and dentin adhesive system (All Bond 2) to the exposed dentin on the intradental nerve activity (INA) and the occluding aspects of dentinal tubules were investigated in cat canine teeth. Single pulp nerve units were dissected from the inferior alveolar nerve and indentified as $A{\delta}$-fiber units. The INAs elicited by 4M NaCl before and after the application of each experimental agent were compared. The morphological changes of exposed dentin surfaces and dentinal tubules in the dentin specimens used to record INAs were observed by SEM. The results obtained were as follows. 1. Eight $A{\delta}$-fiber units (conduction velocity: $8.0{\pm}4.0m$/sec) were identified. 4M NaCl evoked an irregular burst of action potentials which ceased immediately after washing. 2. In 4 $A{\delta}$-fiber units, the change of INA after the application of Gluma Desensitizer was $133.9{\pm}80.7%$ when it was compared with the INA before the application of the same agent. 3. In 4 $A{\delta}$-fiber units, application of All Bond 2 completely abolished the INA induced by 4M NaCl. 4. In specimens applied with Gluma Desensitizer, the formation of hybrid layer as well as the identification of resin penetration and reaction products with proteins in dentinal tubules were not clearly observed in interface between dentin and adhesive resin. In specimens applied with All Bond 2, the gap width of 2-$3{\mu}m$ was formed between exposed dentin and adhesive resin, and the hybrid layer and resin tags were not clearly formed either.

• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1288-1298
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• 2019

Bacterial ATP synthases drive ATP synthesis by a rotary mechanism, and play a vital role in physiology and cell metabolism. Corynebacterium glutamicum is well known as an industrial workhorse for amino acid production, and its ATP synthase operon contains eight structural genes and two adjacent genes, cg1360 and cg1361. So far, the physiological functions of Cg1360 (GenBank CAF19908) and Cg1361 (GenBank CAF19909) remain unclear. Here, we showed that Cg1360 was a hydrophobic protein with four transmembrane helices (TMHs), while no TMH was found in Cg1361. Deletion of cg1360, but not cg1361, led to significantly reduced cell growth using glucose and acetic acid as carbon sources, reduced F1 portions in the membrane, reduced ATP-driven proton-pumping activity and ATPase activity, suggesting that Cg1360 plays an important role in ATP synthase function. The intracellular ATP concentration in the ${\Delta}cg1360$ mutant was decreased to 72% of the wild type, while the NADH and NADPH levels in the ${\Delta}cg1360$ mutant were increased by 29% and 26%, respectively. However, the ${\Delta}cg1361$ mutant exhibited comparable intracellular ATP, NADH and NADPH levels with the wild-type strain. Moreover, the effect of cg1360 deletion on L-valine production was examined in the L-valine-producing V-10 strain. The final production of L-valine in the $V-10-{\Delta}cg1360$ mutant reached $9.2{\pm}0.3g/l$ in shake flasks, which was 14% higher than that of the V-10 strain. Thus, Cg1360 can be used as an effective engineering target by altering energy metabolism for the enhancement of amino acid production in C. glutamicum.