• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2002년도 추계학술대회
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• pp.159-161
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• 2002

Bacteriophage lambda integrase carries out the site-specific recombination of lambda. Integrase contains two DNA binding domains with distinct sequence specificity, namely arm-type binding and core-type binding domains. The amino-terminal arm-binding domain is structurally related to the three-stranded $\beta-sheet$ family of DNA-binding domains. Integrase binding to the high affinity arm-type site by the amino-terminal domain facilitates Int binding to the low affinity core-type site, where the cleavage and strand exchange occurs. The amino-terminal domain of Int also modulates the core-binding and catalysis through intramolecular domain-domain interaction and/or intermolecular interactions between Int monomers. In addition, the amino-terminal domain interacts cooperatively with excisionase during excision. This indicates that amino-terminal domain of Int plays an important role in formation of proper higher-order nucleoprotein structure required for lambda site-specific recombination.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.47-47
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• 2001

Opening of $Ca^{2＋}$ -channels represents the final common pathway for insulin secretion in pancreatic beta-cells and related cell lines. We investigated voltage-sensitive calcium channels (VSCCs) and insulin secretion in RINm5F, an insulinoma cell line derived from rat pancreatic beta-cells. Several types of VSCCs were identified in RINm5f cells： dihydropyridine-sensitive L-type, $\omega$-conotoxin GVIA-sensitive N-type, $\omega$-agatoxin IVA-sensitive P-type channels, and $\omega$-conotoxin MVIIC sensitive Q-type channels.(omitted)

• 대한수학회보
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• 제58권1호
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• pp.235-251
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• 2021

We consider the Schrödinger type operator ��k = (-∆)k+Vk on ℝn(n ≥ 2k + 1), where k = 1, 2 and the nonnegative potential V belongs to the reverse Hölder class RHs with n/2 < s < n. In this paper, we establish the (Lp, Lq)-boundedness of the higher order Riesz transform T��,�� = V2��∇2��-��2 (0 ≤ �� ≤ 1/2 < �� ≤ 1, �� - �� ≥ 1/2) and its adjoint operator T∗��,�� respectively. We show that T��,�� is bounded from Hardy type space $H^1_{\mathcal{L}_2}({\mathbb{R}}_n)$ into Lp2 (ℝn) and T∗��,�� is bounded from ��p1 (ℝn) into BMO type space $BMO_{\mathcal{L}_1}$ (ℝn) when �� - �� > 1/2, where $p_1={\frac{n}{4({\beta}-{\alpha})-2}}$, $p_2={\frac{n}{n-4({\beta}-{\alpha})+2}}$. Moreover, we prove that T��,�� is bounded from $BMO_{\mathcal{L}_1}({\mathbb{R}}_n)$ to itself when �� - �� = 1/2.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2955-2959
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• 2011

Second-order rate constants for nucleophilic substitution reactions of 2,4-dinitrophenyl benzenesulfonate 1a with a series of alicyclic secondary amines in MeCN have been measured spectrophotometrically and compared with those reported previously for the corresponding reactions performed in aqueous medium to investigate the effect of medium on reactivity and reaction mechanism. The amines employed in this study are found to be more reactive in the aprotic solvent than in $H_2O$. The reactions of 1a in MeCN result in a linear Br${\o}$nsted-type plot with ${\beta}_{nuc}$ = 0.58, which contrasts to the curved Br${\o}$nsted-type plot reported previously for the corresponding reactions performed in the aqueous medium (i.e., ${\beta}_2$ = 0.86 and ${\beta}_1$ = 0.38). Accordingly, it has been concluded that the reaction mechanism changes from a stepwise mechanism to a concerted pathway upon changing the medium from $H_2O$ to MeCN. Reactions of Y-substituted phenyl benzenesulfonates 1a-c with piperidine in MeCN result in a linear Br${\o}$nsted-type plot with ${\beta}_{lg}$ = -1.31, indicating that expulsion of the leaving group is significantly more advanced than bond formation in the transition state. The trigonal bipyramidal intermediate ($TBPy^{\pm}$) proposed previously for the reactions in $H_2O$ would be highly unstable in MeCN due to strong repulsion between the negative charge in $TBPy^{\pm}$ and the negative dipole end of MeCN. Thus, destabilization of $TBPy^{\pm}$ in MeCN has been concluded to change the reaction mechanism from a stepwise mechanism to a concerted pathway.

• Journal of the Korean Wood Science and Technology
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• 제44권2호
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• pp.253-263
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• 2016

Fungi, such as the wood-rotting Polyporus brumalis, are excellent sources of pharmaceutically interesting natural products such as sesquiterpenoids. In this study, we investigated the biosynthesis of P. brumalis sesquiterpenoids on modified medium. Ten additional species of white rot fungi were inoculated in medium containing nutrients such as $C_6H_{12}O_6$, $C_4H_{12}N_2O_6$, $KH_2PO_4$, $MgSO_4$, and $CaCl_2$ at $28^{\circ}C$ for 25 days. After 10 days of incubation, eudesmane-type sesquiterpenes, ${\beta}$-eudesmane and ${\beta}$-eudesmol, were only synthesized during the growth phase of P. brumalis. Experiments excluding one nutrient at a time were conducted to determine the effects of inorganic nutrients on sesquiterpene biosynthesis. In conclusion, GC-MS analysis showed that biosynthesis of sesquiterpenes was differentially regulated by inorganic nutrients such as $MgSO_4$, $C_4H_{12}N_2O_6$, and $KH_2PO_4$. We found $MgSO_4$ supplementation to be vital for eudesmane-type sesquiterpene biosynthesis in P. brumalis; nitrogen ($C_4H_{12}N_2O_6$) and phosphate ($KH_2PO_4$) inhibited the synthesis of P. brumalis metabolites. Magnesium is a known cofactor of sesquiterpene synthase, which promotes ${\beta}$-eudesmol synthesis. To mechanistically understand eudesmane-type sesquiterpene biosynthesis in P. brumalis, further research into the genes regulating the dynamics of such biosynthesis is warranted.

• 대한한방내과학회지
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• 제29권3호
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• pp.787-799
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• 2008

Objective : Diabetic nephropathy is the most common cause of end stage renal disease. AGE, $TGF-{\beta}1$ type IV collagen, and macrophage/monocyte infiltration are the main factors of diabetic nephropathy. We investigated the effects of Salvia miltiorrhiza on renal function and histopathological changes in streptozotocin(STZ)-induced diabetic nephropathy rat model. Methods : Diabetes was induced in male Sprague-Dawley rats(290${\pm}$10g) by injecting STZ(45mg/kg) into the tail vein. Rats were divided into 3 groups(n = 6): normal, control, and salvia. After 8 weeks of administration of Salvia miltiorrhiza extract on the Salvia group, we checked 24 hrs urine, blood biochemistry and renal tissue to evaluate renal function and histopathological changes by examining parameters including albuminuria, BUN, creatinine, cholesterol, LDL, TG, macrophage/monocyte antigen(ED-1), $TGF-{\beta}1$, AGE, and type IV collagen. Results : Salvia miltiorrhiza decreased the amount of 24hrs proteinuria, and inhibited histopathological changes of diabetic nephropathy including the expression and accumulation of various factors which could promote development of diabetic nephropathy. Conclusion : These findings suggest that Salvia miltiorrhiza might protect the renal function and inhibit the development of renal injury by regulating factors including AGE, $TGF-{\beta}1$ Type IV collagen, macrophage and monocyte infiltration. So Salvia miltiorrhiza can be used for diabetic patients to prevent the progression of diabetic nephropathy.

• 한국약용작물학회지
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• 제3권1호
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• pp.21-24
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• 1995

생열귀나무의 열매를 약용 또는 건강식품으로서 의 실용화 가능성을 검토하기 위한 목적의 일환으로 과실을 대원형(大圓形), 타원형(楕圓形) 및 소원형(小圓形)으로 분류하여 ascorbic acid와 ${\beta}-carotene$의 함량을 분석한 결과를 요약하면 다음과 같다. 1. Ascorbic acid의 함량은 대원형(大圓形)에서 건중(乾重) 100g 당(當) 911mg으로 가장 높았으며 타원형(楕圓形) 358mg, 소원형(小圓形) 344mg으로서 비교적 그 함량이 낮았다. 2. ${\beta}$-carotene의 함량은 타원형(楕圓形)에서 건중(乾重) 100g 당(當) 286mg으로 가장 높았으며 대원형(大圓形)도 208mg으로 비교적 높은 편이었으나 소원형(小圓形)은 24mg으로 매우 낮게 나타났다. 3. 종자(種子)의 ascorbic acid는 과육(果肉)보다 1/10 - 1/30의 수준이었으며 과육의 조추출물은 대원형(大圓形)과 소원형(小圓形)은 각각 2,600mg 및 2,700mg 이었으나 타원형(楕圓形)은 1,060mg로 낮은 함량을 나타내었다.

• Clinical and Experimental Pediatrics
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• 제57권10호
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• pp.440-444
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• 2014

Purpose: Febrile seizures are induced by fever and are the most common type of seizures in children. Although numerous studies have been performed on febrile seizures, their pathophysiology remains unclear. Recent studies have shown that cytokines may play a role in the pathogenesis of febrile seizures. The present study was conducted to identify potential links between serum interleukin-1beta (IL-$1{\beta}$), tumor necrosis factor-alpha (TNF-${\alpha}$), and febrile seizures. Methods: Ninety-two patients with simple or complex febrile seizures (46 patients per seizure type), and 46 controls with comparable age, sex, and severity of temperature were enrolled. Results: The median concentrations of serum IL-$1{\beta}$ in the simple, complex febrile seizure, and control groups were 0.05, 0.1, and 0.67 pg/mL, respectively (P=0.001). Moreover, the median concentrations of TNF-${\alpha}$ in the simple, complex febrile seizure, and control groups were 2.5, 1, and 61.5 pg/mL, respectively (P=0.001). Furthermore, there were significant differences between the case groups in serum IL-$1{\beta}$ and TNF-${\alpha}$ levels (P<0.05). Conclusion: Unlike previous studies, our study does not support the hypothesis that increased IL-$1{\beta}$ and TNF-${\alpha}$ production is involved in the pathogenesis of febrile seizures.

• IMMUNE NETWORK
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• 제13권5호
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• pp.194-198
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• 2013

Recent papers have shown that the initial event in the pathogenesis of autoimmune type 1 diabetes (T1D) comprises sensing of molecular patterns released from apoptotic ${\beta}$-cells by innate immune receptors such as toll-like receptor (TLR). We have reported that apoptotic ${\beta}$-cells undergoing secondary necrosis called 'late apoptotic' ${\beta}$-cells stimulate dendritic cells (DCs) and induce diabetogenic T cell priming through TLR2. The role of other innate immune receptors such as TLR7 or TLR9 in the initiation of T1D has also been suggested. We hypothesized that TLR2 blockade could inhibit T1D at the initial step of T1D. Indeed, when a TLR2 agonist, $Pam3CSK_4$ was administered chronically, the development of T1D in nonobese diabetic (NOD) mice was inhibited. Diabetogenic T cell priming by DCs was attenuated by chronic treatment with $Pam3CSK_4$, indicating DC tolerance. For the treatment of established T1D, immune tolerance alone is not enough because ${\beta}$-cell mass is critically reduced. We employed TLR2 tolerance in conjunction with islet transplantation, which led to reversal of newly established T1D. Dipeptidyl peptidase 4 (DPP4) inhibitors are a new class of anti-diabetic agents that have beneficial effects on ${\beta}$-cells. We investigated whether a combination of DPP4 inhibition and TLR2 tolerization could reverse newly established T1D without islet transplantation. We could achieve normoglycemia by TLR2 tolerization in combination with DPP4 inhibition but not by TLR2 tolerization or DPP4 inhibition alone. ${\beta}$-cell mass was significantly increased by combined treatment with TLR2 tolerization and DPP4 inhibition. These results suggest the possibility that a novel strategy of TLR tolerization will be available for the inhibition or treatment of established T1D when combined with measures increasing critically reduced ${\beta}$-cell mass of T1D patients such as DPP4 inhibition or stem cell technology.

• Journal of Pharmaceutical Investigation
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• 제27권1호
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• pp.29-38
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• 1997

Precipitation was formed during the preparation of decoction from a mixture of Scutellariae Radix and Coptidis Rhizoma. Baicalin and berberine were identified in this coprecipitated product (CPP) and these components were the active ingredients of two herbal medicine. We extracted respectively crude baicalin and berberine in Scutellariae Radix and Coptidis Rhizoma and prepared coprecipitate of crude baicalin-berberine. To increase the stability and bioavailability of coprecipitate of crude baicalin-berberine(CBB), which is slightly soluble drug, its inclusion complex was prepared and studied in this experiment. Inclusion complex of CBB with ${\beta}-cyclodextrin(CBB-{\beta}-CD)$ was prepared by freeze drying method and its characteristics were ascertained by means of solubility test, differential thermal analysis(DTA) and scanning electron microscope(SEM). The type of $CBB-{\beta}-CD$ is classified as $A_L-type$ on phase solubility diagram, and the stoichiometric ratio of CBB(baicalin in CBB) : ${\beta}-CD$ complex is 1:1 and formation constant is 151 $M^-1$. The solubility, dissolution, in situ absorption and serum concentration of $CBB-{\beta}-CD$ were significantly increased when compared to CBB. Therefore enhanced bioavailability of CBB by inclusion complexation with ${\beta}-cyclodextrin$ might be useful for dosage form design of active ingredients of two herbal medicine.