• Journal of the Korean Magnetic Resonance Society
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• v.16 no.2
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• pp.147-161
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• 2012

Human melanocortin-4 receptor (hMC4R) among MC-Rs, expressed in the brain, is in charge of the control on energy homeostasis and food intake. The structure and function of human MC4R have been studied to understand their essential function and roles. To investigate the structure and function, it is necessary to prepare sufficient amounts of proteins. However, their expression and purification is demanding and time-consuming due to their innate insoluble and toxic properties. The heterozygous mutations of hMC4R, exchange of Asp 90 to Asn located in second transmembrane, cause severe obesity in human. To obtain purified hMC4R wt-TM2 for structural studies, it was first over-expressed and purified by fast protein liquid chromatography (FPLC) and then solution NMR studies were performed to get high-resolution spectra. In here, we established optimized purification scheme to get more purified target peptide.

• Membrane and Water Treatment
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• v.9 no.2
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• pp.87-94
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• 2018

The interactions of water soluble polymers with dye are studied by ultrafiltration using a molecular weight cut off of 10 KDa regenerated cellulose ultrafiltration membrane. Two water-soluble polymers, namely Poly (Sodium-4 Styrenesulfonate) (PSS) and Poly (Vinyl Alcohol) (PVA) were selected for this study. The effects of process parameters, such as, polyelectrolyte concentrations, transmembrane pressure, ionic strength and pH of solution on dye retention and permeation flux were examined. PSS enhanced ultrafiltration achieved dye retention as high as 99% as a result of complexation between polyanion containing aromatic groups and cationic dye. This result was confirmed by the red shift. The retention of dye decreases as the salt concentration increases, a high retention was obtained at pH above 4. However, in case of PVA, relatively low retention (50%) was observed. Ionic strength and pH has no significant effect on the removal of MB. The permeate flux depended slightly on polyelectrolytes concentrations, transmembrane pressure, salt concentration and pH.

• Biomedical Science Letters
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• v.29 no.4
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• pp.336-343
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• 2023

Lung cancer is one of the cancers with high mortality and incidence rates worldwide. Although, various anticancer research efforts are underway to completely treat cancer, the challenge against it remains in the inability to eliminate cancer stem cells (CSCs), leading to difficulties in curing the cancer and resulting in recurrence. As a result, there is a growing interest in the discovery of new biomarkers and therapeutic molecules that can simultaneously target both cancer cells and CSCs. From this point of view, we focused on fibronectin leucine rich transmembrane protein 3 (FLRT3), one of the genes known to be present in human lung cells and the discovery from our previous cancer proteomic analysis study. This study aimed to evaluate the potential of FLRT3 as a specific therapeutic biomarker for lung cancer and Lung Cancer-derived-Stem Cells (LCSC). Also, to estimate the biological function of FLRT3 in cancer and LCSC, short hairpin RNA (shRNA) was generated and showed the ability of the decreased-cell migration and cell proliferation of lung cancer through ERK signaling pathway when FLRT3 was knock-downed. In conclusion, our study is the first to report that FLRT3 has the potential as therapeutic biomarker for the treatment of lung cancer and LCSC.

• KSBB Journal
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• v.14 no.2
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• pp.230-234
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• 1999

To improve the crossflow untrafiltration flux, we applied periodic oscillations in transmembrane pressure gradient in order to promote fluid turbulence by inducing repeated compression and relaxation of the cake/gel layer. The oscillatory forms used were square-, sine-, triangle-wave, and pumping interruption. The permeate flux profiles were mathematically simulated and compared with the experimental data. The result showed the periodic pumping interruption most effectively improved the overall flux by up to about 32%. Enough pumping off-time, at least on the order of tens of seconds, was needed to allow the solutes in the layer to diffuse back to the bulk phase. It was better to start the oscillations earlier before the layer was fully established. The square-wave oscillation yielded about 11% increase, which was particularly pronounced in the later part of the filtration. Either the amplitude or the period of the oscillations resulted little influence on flux.actate ester, and lactate ester produced in esterification reaction was distilled simultaneously with hydrolysis reaction into lactic acid. When the yields of lactic acid recovered by batch reactive distillations with various alcohols were compared, the yield of lactic acid was increased as the volatility of lactate ester was increased. In this batch reactive distillation, because the mixtures condensed in partial condensor were flown to reboiler through distillation column, the recovery yield of lactic acid was affected by operation temperature of partial condensor. Hydrolysis reaction into lactic acid in distillation column rarelyoccurred because of short retention time of lactate ester and water. Lactate ester was reacted into lactic acid in reboiler.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.4
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• pp.1391-1398
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• 2010

Reuse feasibility of MBR effluent of S Electronic Company's organic wastewater as a LCD process water was investigated by a $32m^3/d$ pilot-scale RO membrane process. The effects of operating pressure and permeate flux at constant 85% recovery of RO membrane process using MBR effluent were analyzed for transmembrane pressure and period for CIP by membrane fouling as well as rejection of TOC and conductivity. MBR effluent requires additional treatment to meet the LCD process water quality criteria of TOC<1 mg/L and conductivity<$100{\mu}S/cm$ which is stringent as compared with those of conventional reuse water quality criteria. The RO process operated at 85% recovery with stepwise increasing of permeate fluxes from 12.5 LMH to 22.0 LMH was able to meet LCD process water quality criteria. However, the transmembrane pressure increased and the period of CIP decreased as increasing permeability fluxes due to fouling of RO membrane. The optimum operational conditions of RO membrane process were permeate fluxes of 16.5~18.5 LMH with operating pressure of $6.7{\sim}12.4kgf/cm^2$ and CIP period of 20~25 days at constant 85% recovery.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.47-52
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• 1968

Twenty white rabbits anesthetized with nembutal (30 mg/kg) were employed in this experiment. Five of them served as controls; the remaining rabbits as experimental group were subjected to irreversible hemorrhagic shock. Shock was induced by bleeding the animals until mean blood pressure decreased to a level of 50-40 mmHg. This level of pressure was maintained for 3-4 hours, after which the drawn blood was reinfused. The reinfusion of blood caused the elevation of arterial pressure almost the control level for some minutes, after which a gradual and progressive decline of blood pressure became evident. This decline was thought to be the result from irreversible hemorrhagic shock. When mean blood pressure declined to less than 50 mmHg, chest was opened and samples of arterial blood and left ventricular muscle were taken. Left ventricular muscle and blood plasma were analyzed for potassium, sodium, chloride and water content. Blood glucose concentration was determined by Somogyi-Nelson's method. Extracellular and intracellular myocardial water and electrolyte content were calculated on the basis that electrolytes are distributed between plasma water and interstitial water according to Gibbs-Donnan equilibrium. In this calculation extracellular water was substituted for Na space. The findings obtained were as follows: 1. The concentration of blood glucose was 87mg% in the controls and it rose to 222 mg% in shock (P<0.01). 2. Plasma potassium elevated significantly from 3.3 mEq/l in controls to 8.0 mEq/l in shock (P<0.01), while small decreases in sodium (151-146 mEq/l) and chloride (102-96 mEq/l) were observed (P<0.3, P<0.1), 3. The changes of blood water content (83.1-84.3%) and cardiac water content (77.5-78.3 gm/100gm WT) were observed. 4. In control animals myocardial potassium levels which averaged 30.2 mEq/100 gmDT rose significantly to 40.3 mEq/100 gmDT in shock (P<0.01), while moderate decreases in sodium(16.3-14.3 mEq/100 gmDT) were observed in shock. 5. The calculated transmembrane resting potential of left ventricular muscle of control animals averaged 95 mV, while rabbits in shock averaged 77 mV. (P <0.01). The findings of this experiment do not correspond with the conclusions that myocardial depression seems to be the cause of irreversible hemorrhagic shock, because the excitability of heart muscle is elevated. From the point of view that the lowered transmembrane resting potential, the cause of death in terminal stage of irreversible hemorrhagic shock may be ventricular fibrillation. It can't be said, however, that the lowered transmembrane resting potential is responsible for the transition from reversible to irreversible hemorrhagic shock. The marked increase in blood glucose suggested that glycogenolysis in the liver is favorably active in shock.

• Journal of Life Science
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• v.25 no.1
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• pp.84-92
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• 2015

Interferon inducible transmembrane protein (IFITM) family genes have been implicated in various cellular processes such as the homotypic cell adhesion functions of IFNs and cellular anti-proliferative activities. The present study aimed to investigate whether the polymorphisms of the IFITM2 and IFITM5 genes are associated with susceptibility to UC. We identified a total of thirteen polymorphisms (eleven SNPs and two variations) in the IFITM2 gene and twelve polymorphisms (eleven SNPs and one variation) in the IFITM5 gene, by the direct sequencing method. Genotype analysis in the IFITM2 and IFITM5 SNPs was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and Taq-Man probe analysis, and the haplotype frequencies of IFITM2 and IFITM5 SNPs for multiple loci were estimated using the expectation maximization (EM) algorithm. The genotype and allele frequencies of IFITM2 SNPs, as well as IFITM5 SNPs, in UC patients were not significantly different from those of the healthy controls. We also analyzed the combined frequencies of rs77537847 of IFITM1, rs909097 of IFITM2, and rs56069858 of IFITM5 in the UC patients and the healthy controls. Although the distribution of the major combined genotype frequency did not differ significantly between the healthy controls and the UC patients, the GGT combined frequency in the healthy controls was significantly different from that in the UC patients (P=0.002). This result suggests that the combined genotype of the IFITMs polymorphisms may be associated with a susceptibility to UC and could be a useful genetic marker for UC.

• Korean Journal of Microbiology
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• v.41 no.4
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• pp.255-261
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• 2005

A 6.7kb DNA fragment containing the sprT gene encoding Streptomyces griseus trypsin (SGT) was cloned from Streptomyces griseus ATCC 10137, and the complete nucleotide sequence was determined. Nucleotide sequence and deduced amino acid or the EcoRI-HindIII fragment revealed the presence or the six complete ORFs containing the sprT gene and one incomplete ORF, which were named ORF1, SGT, ORF2, ORF3, ORF4, ORF5, and ORF6, respectively. ORF1 has homology with the oxidoreductases from several organisms. ORF2 and ORF3 show similarity with unknown proteins and transcription regulator that belongs to the ArsR family, respectively. ORF4 and ORF5 show homology with the peptidoglycan bound protein with LPXTG motif from Listeria monocytogenes and the membrane protein with transmembrane helix from several organisms, respectively. The last ORF, ORF6, shows homology with the lipoprotein from Streptomyces avermitilis.

• Journal of Korean Society of Water Science and Technology
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• v.26 no.6
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• pp.61-72
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• 2018

In this study, applicability of the decentralized water supply system were investigated by the high flux evaluation using ceramic membrane with combined pretreatment process. A) filtration process increased the transmembrane pressure of 1.4 kPa and 89.5 kPa on 2 and $5m^3/m^2{\cdot}d$ of filtration flux, respectively, the physical backwashing recovery rate were less than 28.6%. The (B) Coag./Floc. - Sedi. combined process with 4 mg / L of A-PAC showed that the transmembrane pressure increased to within 6 kPa, the physical backwashing recovery rate was over 37.9 % higher than (A) Filtration process. (C) Coag./Floc. combined process showed an increase of transmembrane pressure compared with (B) Coag./Floc. - Sedi. combined process, physical backwashing recovery rate was over 84%. As a result of the membrane fouling analysis using the resistance in series model, the combined pretreatment process showed that the cake resistance (Rc) was more than 92% at membrane filtration flux of $2m^3/m^2{\cdot}d$. In the (C) Coag./Floc. combined process, cake resistance(Rc) was over 86% on high flux conditions. The coagulation floc contained in influent was removed by the membrane, and the cake layer formed with the removed floc was identified as reversible fouling resistance which could be recovered by physical backwashing. The decentralized water supply system, which has the limitation of site area and installation space, is considered to could be operation of high flux of ceramic membrane by applying (C) Coag./Floc. combined process without sedimentation process.

• BMB Reports
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• v.37 no.1
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• pp.114-121
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• 2004

Ion channels of the transient receptor potential (TRP) superfamily are non-selective cationic channels with six transmembrane domains. The TRP channel made its first debut as a light-gated $Ca^{2+}$ channel in Drosophila. Recently, research on animal sensation in Drosophila disclosed other members of the TRP family that are required for touch sensation and hearing as well as the sensation of painful stimuli.