• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1413-1420
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• 2014

Phytate is an antinutritional factor that impacts the bioavailability of essential minerals such as $Ca^{2+}$, $Mg^{2+}$, $Mn^{2+}$, $Zn^{2+}$, and $Fe^{2+}$ by forming insoluble mineral-phytate salts. These insoluble mineral-phytate salts are hydrolyzed rarely by monogastric animals, because they lack the hydrolyzing phytases and thus excrete the majority of them. The ${\beta}$-propeller phytases (BPPs) hydrolyze these insoluble mineral-phytate salts efficiently. In this study, we cloned a novel BPP gene from a marine Pseudomonas sp. This Pseudomonas BPP gene (PsBPP) had low sequence identity with other known phytases and contained an extra internal repeat domain (residues 24-279) and a typical BPP domain (residues 280-634) at the C-terminus. Structure-based sequence alignment suggested that the N-terminal repeat domain did not possess the active-site residues, whereas the C-terminal BPP domain contained multiple calcium-binding sites, which provide a favorable electrostatic environment for substrate binding and catalytic activity. Thus, we overexpressed the BPP domain from Pseudomonas sp. to potentially hydrolyze insoluble mineral-phytate salts. Purified recombinant PsBPP required $Ca^{2+}$ or $Fe^{2+}$ for phytase activity, indicating that PsBPP hydrolyzes insoluble $Fe^{2+}$-phytate or $Ca^{2+}$-phytate salts. The optimal temperature and pH for the hydrolysis of $Ca^{2+}$-phytate by PsBPP were $50^{\circ}C$ and 6.0, respectively. Biochemical and kinetic studies clearly showed that PsBPP efficiently hydrolyzed $Ca^{2+}$-phytate salts and yielded myo-inositol 2,4,6-trisphosphate and three phosphate groups as final products. Finally, we showed that PsBPP was highly effective for hydrolyzing rice bran with high phytate content. Taken together, our results suggest that PsBPP has great potential in the animal feed industry for reducing phytates.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.5 no.1
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• pp.54-60
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• 2019

Sentinel lymph node (SLN) imaging plays an important role in surgery of patients with breast cancer and melanoma. In this study, avidin (Av), a tetrameric protein glycosylated with mannose and N-acetylglucosamine molecules, was labeled with $^{64}Cu$ and then evaluated for LN imaging. $^{64}Cu$-Labeled $NeutrAvidin^{TM}$ (NAv), a non-glycosylated form of Av, was used for comparison. 1,4,7,10-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA)-conjugated Av and NAv were prepared from the corresponding proteins and DOTA-NHS ester, which were then labeled with copper-64 and purified using PD-10 columns. The numbers of DOTA molecules conjugated to Av and NAv were 4.9 and 3.3, respectively. [$^{64}Cu$]Cu-DOTA-conjugated Av and NAv were prepared in 93% and 73% radiochemical yields, respectively. In vitro serum stability study showed that copper-64 remained stable on all radiotracers for 24 h (>97%). MicroPET/CT images showed that high radioactivity was accumulated in LNs within 15 min after footpad-injection of radiotracers. Tissue distribution data of mice demonstrated significantly higher uptake in the popliteal (PO) LN than lumbar (LU) LN for $^{64}Cu$-labeled Av (relative % ID/g excluding the injection sites: 66.2% and 26.0%, respectively) compared with those of $^{64}Cu$-labeled NAv (43.0% and 49.2%, respectively). The results of this study suggest that mannose molecules on Av enabled the radiotracer to retain in the first LN after mouse footpad-injection.

• The Korea Journal of Herbology
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• v.28 no.3
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• pp.69-74
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• 2013

Objectives : Since hypopigmentation is known to increase the risk of skin cancer, melanogenesis in the skin needs to be regulated. Here, we evaluated the melanogenesis stimulatory effects of a modified Goagium herbal remedy (HR) and HR+ox bile (Bos taurus domesticus) extract (OBE) to address hypopigmentation disorders. Methods : B16F10 melanoma cells were treated with different dosages of HR and HR+OBE for 24 to 48 h after 1 h of 10 nM ${\alpha}$-melanocyte stimulating hormone (${\alpha}$-MSH). After the treatment, cell viability, tyrosinase activity, melanin synthesis and the expression of genes related to melanin synthesis were measured and the regulation of the ${\alpha}$-MSH signalling through cAMP responding element binding protein (CREB) was determined. Results : HR and HR+OBE with the ranges of $15{\sim}100{\mu}g/mL$ did not affect cell viability in melanoma cells. The 1 h treatment of HR+OBE (50 and $100{\mu}g/mL$) potentiated the phosphorylation of CREB by enhancing ${\alpha}$-MSH signaling and its 24 h treatment increased CREB expression. Consistent with CREB potentiation, their treatment for 24 h, the expression of microphthalmia-associated transcription factor (MIFT), tyrosinase, tyrosinase related protein (TRP)-1 and TRP-2 were increased in realtime PCR. Ultimately, the 48 h treatment of HR+OBE (50 and $100{\mu}g/mL$) increased tyrosniase activity and melanin contents in the melanoma cells in comparison to the control. Conclusions : HR+OBE (50 and $100{\mu}g/mL$) increases melanin synthesis in B16F10 melanoma cells via the stimulation of tyrosinase activity and expression of MIFT, tyrosinase, TRP-1 and TRP-2. HR+OBE can be used as the a possible treatment for hypopigmentation of the skin.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.94-94
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• 2003

Endocrine disrupters (EDs) are exogenous chemicals that interfere with the production, releasing, metabolism, excretion, binding of natural hormones, and whole endocrine systems. EDs are very dangerous since they are extremely stable, not easily degraded, and accumulated in fat and tissue. 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) is known as the most toxic EDs. Therefore, this study was conducted to investigate the effects of TCDD on proliferation of human breast cancer (MCF-7) and endometrial adenocarcinoma (Hec-1B) cells. 10, 100, and 1000 nM of TCDD were treated with steroid free condition. Viable cell counting, MTT, and BrdU assay was performed to investigate cell proliferation. Apoptosis was investigated using DNA laddering. Although, DNA fragmentation as the evidence of apoptosis was not detected, all of these cell lines showed restricted proliferation at 48 hrs after 100 and 1000 nM TCDD treatments. Recently, it has been reported that the expression of transforming growth factor $\beta$s (TGF-$\beta$s) are increased in TCDD treatment and also involved in regulation of cell cycle. Therefore, these results were considered that the decreased cell prolifcration by TCDD is related to the expression of TGF-$\beta$s.

• Macromolecular Research
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• v.11 no.1
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• pp.47-52
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• 2003

The objective of this study was to develop a polymeric drug delivery system for camptothecin (CPT), capable of improving its therapeutic index and reducing its side effects. A monomeric conjugate, 3,6-endo-methylene-1,2,3,6-tetrahydrophthalimidoethanoylcamptothecin in (ETECPT) between CPT and 3,6-endo-methylene-1,2,3,6-tetrahydrophthalimidoethanoic acid was synthesized. Its homo-and copolymer with acrylic acid (AA) were prepared by photopolymerization using 2,2-dimethoxy-2-phenylacetophenone (DMP) as a photoinitiator. The monomer and its polymers were characterized by IR, $^1$H- and $^{13}$ C-NMR spectra. The ETECPT content in poly(ETECPT-co-AA) obtained by elemental analysis was 82 wt%. The number-average molecular weights of the polymers determined by gel permeation chromatography were as follows: M$_{n}$ = 11,400 for poly(ETECPT), M$_{n}$ = 17,900 for poly(ETECPT-co-AA). The $IC_{50}$/ values of ETECPT and its polymers against cancer cells were much larger than that of CPT. Our results from the in vivo antitumor activity indicated that all polymers show high antitumor activity than CPT at a dose of 100 mg/kg./kg.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.76-77
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• 2002

Ras expression has been suggested as a marker for tumor aggressiveness of breast cancer including the degrees of invasion and tumor recurrence. Expression of H-, K-, and N-ras is regulated in a tissue-specific manner and during development, indicating that ras proteins may have different cellular functions.(omitted)

• The Korean Journal of Applied Statistics
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• v.24 no.4
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• pp.633-646
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• 2011

Clinical vaccines studies (that include cancer prevention vaccines and therapeutic vaccines) are ongoing to improve the quality of life and lengthen the human lifespan. Recently clinical trials and research on vaccines have become more active due to the prevalence of new viruses such as the A(H1N1) virus that freighted the whole word in 2009. In this paper we will describe the statistical aspects of clinical vaccine trials and outline the current situation of domestic and international vaccine development.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.42-47
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• 1999

Phorbol ester, growth factors activities are mediated by unclear transcription factors, the c-Fos and c-Jun, which can regulate transcriptional activation through specific DNA sites and by forming the transcription factor AP-l, which usually mediates cell proliferation and differentiation signals. We explored effects of Pini Folium extract (API-l) on AP-l activity. Western blot analysis confirmed that API-l decreased levels of c-Fos or c-Jun protein induced by the tumor promoter Phorbol 12-myristate 13-acetate (PMA; 200 nM). Transient transfection assays with a c-fos promoter reporter construct showed that API-l decreased transcription activity by ore than 50~60%. However, treatment of API-l activity studied further. The main substances were fractionated into dichloromethane layer. Futhermore, API-l extract repressed the [$^3H$]-thymidine uptake in C6 glioma cells, indicating that this extract could be included in a new type of modulator in the mitogenesis.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.693-699
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• 2010

An antiproliferative ribonuclease with a new N-terminal sequence was purified from fruiting bodies of the edible wild mushroom Russula delica in this study. This novel ribonuclease was unadsorbed on DEAE-cellulose, but absorbed on SP-Sepharose and Q-Sepharose. It had a molecular mass of 14 kDa, as judged by fast protein liquid chromatography on Superdex 75 and SDS-polyacrylamide gel electrophoresis. Its optimal pH and optimal temperature were pH 5 and $60^{\circ}C$, respectively. The ranking of its activity toward various polyhomoribonucleotides was poly C> poly G>poly A>poly U. It could inhibit proliferation of HepG2 and MCF-7 cancer cells with an $IC_50$ value of $8.6\;{\mu}M$ and $7.2\;{\mu}M$, respectively. It was devoid of antifungal and HIV-1 reverse transcriptase inhibitory activity.

• Natural Product Sciences
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• v.6 no.3
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• pp.147-150
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• 2000

The extracts of Carica papaya (flower), Barringtonia macrostachya (leaves), Coleus tuberosus (tuber), Mangifera indica (fruit skin) and Eugenia polyantha (leaves) showed strong in vitro anti-tumor promoting activity when assayed using Raji cells (Mooi et al., 1999). The antitumor promoting activity of the crude extracts was further analyzed by immunoblotting analysis of Raji cells carving Epstein-Barr virus genome. The expression of early antigens diffuse (EA-D) and early antigens restricted (EA-R) was determined by performing western blotting of treated Raji cells with human sera of nasopharyngeal carcinoma patients. All the plant extracts were shown to be able to suppress both EA-D and EA-R.