• Microbiology and Biotechnology Letters
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• v.39 no.1
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• pp.93-96
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• 2011

It has been shown that a nucleotide substitution at position 770 in Escherichia coli 16S rRNA, which is implicated in forming the evolutionary conserved B2c intersubunit bridge, has a detrimental effect on ribosome function. In order to isolate second-site revertants that complement ribosomes containing C770G, we performed a random mutagenesis of the 16S rRNA gene and selected clones that could produce more CAT protein translated by specialized ribosome. One of the clones contained two nucleotide substitutions at positions 569 and 904 (C569G and U904C) and these mutations partially complemented the loss of protein-synthesis ability caused by C770G. Further studies using the isolated revertant will provide information about which part of 16S rRNA is interacting with C770 and the consequence of the structure formed by these interactions in the process of protein synthesis.

• Nutrition Research and Practice
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• v.10 no.1
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• pp.11-18
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• 2016

BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. $\small{D}$-xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of $\small{D}$-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with $\small{D}$-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with $\small{D}$-xylose. These groups were maintained for two weeks. The effects of $\small{D}$-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic ${\beta}$-cells were analyzed. RESULTS: In vivo, $\small{D}$-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. $\small{D}$-xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of $\small{D}$-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with $\small{D}$-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, $\small{D}$-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, $\small{D}$-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by ${\beta}$-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.

• The Plant Pathology Journal
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• v.15 no.1
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• pp.21-27
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• 1999

Nonpathogenic mutants of Xanthomonas campestris pv. glycines were generated with Omegon-Kim to isolate genes essential for pathogenicity and inducing hypersensitive response (HR). Three nonpathogenic multants and two mutants showing slow symptom development were isolated among 1,000 colonies tested. From two nonpathogenic mutants, 8-13 and 26-13, genes homologous to hrcC and hrpF of X. campestris pv. vesicatoria were identified. The nonpathogenic mutant 8-13 had a mutation in a gene homologous to hrpF of X. campestris pv. vesicatoria and failed to cause HR on pepper plants but still induced HR on tomato leaves. The nonpathogenic mutant 26-13 had an insertional mutation in a gene homologous to hrcC of X. campestris pv. vesicatoria and lost the ability to induce HR on pepper leaves but still caused HR on tomato plants. Unlike other phytopathogenic bacteria, the parent strain and these two mutants of X. campestris pv. glycines did not cause HR on tobacco plants. a cosmid clone, pBL1, that complemented the phenotypes of 8-13 was isolated. From the analysis of restriction enzyme mapping and deletion analyses of pBL1, a 9.0-kb Eco RI fragment restored the phenotypes of 8-13. pBL1 failed to complement the phenotypes of 26-13, indicating that the hrcC gene resides outside of the insert DNA of pBL1. One nonpathogenic mutant, 13-33, had a mutation in a gene homologous to a miaA gene encoding tRNA delta (2)-isopentenylpyrophosphate transferase of Escherichia coli. This indicated that tRNA modifications in X. campestris pv. glycines may be required for expression of genes necessary for pathogenicity. The mutant 13-33 multiplied as well as the parent strain did in the culture medium and in planta, indicating that loss of pathogenicity is not due to the inability of multiplication in vivo.

• Tuberculosis and Respiratory Diseases
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• v.68 no.5
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• pp.294-297
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• 2010

Although $Taxo^{(R)}$ is one of the most successful drugs in current cancer chemotherapy against solid tumors, a major problem is hypersensitivity reactions that arises as a consequence of activation of the complement (C) system, "C activation-related pseudo-allergy". Most severe hypersenstivity reactions occur within the first few minutes of $Taxo^{(R)}$ administration, usually after the first or second dose. Here we report a case of a severe hypersensitivity reaction in a 72-year-old man undergoing $Genexol-PM^{(R)}$ infusion. Hypotension and polymorphic pruritic skin rash appeared 2 hours after the start of $Genexol-PM^{(R)}$ infusion (with an appropriate premedication). Treating with methylprednisolone, epinephrine and inotropic agents, reduced the hypotension and the skin rash disappeared. We report this case with a review of the literature.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.3
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• pp.235-244
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• 2007

By comparing the proteins from the workers exposed to styrene with the ones from controls, it may be possible to identify proteins that play a role in the occurrence and progress of occupational disease and thus to study the molecular mechanisms of occupational disease. In order to find the biomarkers for assessing the styrene effects early, before clinical symptoms develop and to understand the mechanisms of adverse health effects, we surveyed 134 employees, among whom 52 workers(30 male and 22 female) were chronically exposed to styrene in 10 glass-reinforced plastic boat manufacturing factories in Korea and 82 controls had never been occupationally exposed to hazardous chemicals including styrene. The age and drinking habits and serum biochemistry such as total protein, BUN and serum creatinine in both groups were significantly different. Exposed workers were divided into three groups according to exposure levels of styrene(G1, below 1/2 TLV; G2, 1/2 TLV to TLV; G3, above TLV). The mean concentration of airborne styrene in G1 group was $10.93{\pm}11.33ppm$, and those of urinary mandelic acid(MA) and phenylglyoxylic acid(PGA) were $0.17{\pm}0.21$ and $0.13{\pm}0.11g/g$ creatinine, respectively. The mean concentration of airborne styrene in G2 and G3 groups were $47.54{\pm}22.43$ and $65.33{\pm}33.47ppm$, respectively, and levels of urinary metabolites such as MA and PGA increased considerably as expected with the increase in exposure level of styrene. The airborne styrene concentration were significantly correlated to the urinary concentration of MA(r=0.784, p=0.000) and PGA(r=0.626, p<0.001). In the 2D electrophoresis, the concentration of five proteins including complement C3 precursor, alpha-1-antitrypsin(AAT), vitamin D binding protein precursor(DBP), alpha-1-B-glycoprotein(A1BG) and inter alpha trypsin inhibitor(ITI) heavy chain-related protein were significantly altered in workers exposed to styrene compared with controls. While expression of complement C3 precursor and AAT increased by exposure to styrene, expression of DBP, A1BG and ITI heavy chain-related protein decreased. These results suggest that the exposure of styrene might affects levels of plasma proteinase, carriers of endogenous substances and immune system. In particular, increasing of AAT with the increase in exposure level of styrene can explain the tissue damage and inflammation by the imbalance of proteinase/antiproteinase and decrease of DBP, A1BG and ITI heavy chain-related protein in workers exposed to styrene is associated with dysfunction and/or declination in immune system and signal transduction

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.97-103
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• 2015

Until recently, the three conventional evaluation methods, which are instrumental (Chromameter$^{(R)}$ CR-400 and Mexameter$^{(R)}$ M18) and visual assessments have been used frequently for skin color evaluation. However, we took notice the potential of image analysis as a new tool to evaluate color change of skin. To reveal the reliability of the image analysis for the evaluation of whitening agents, 34 healthy female volunteers with hyperpigmentation were recruited, and the selected volunteers applied the whitening products containing Vitamin C twice a day in the morning and evening and received iontophoresis treatments once a week for 8 weeks. The changes in hyperpigmentation evaluated by Chromameter$^{(R)}$, Mexameter$^{(R)}$ and visual assessment were compared with the results from the image analysis. As with $L^*$ value trends of the analysis using Chromameter$^{(R)}$, the V value from the image analysis increased after applying the test products compared with baseline values. Furthermore, V value showed a positive correlation with $L^*$ value (r = 0.494, p < 0.01) and negative correlation with MI (r = - 0.683, p < 0.01) and VG (r = - 0.549, p < 0.01). Therefore, image analysis may be considered as an effective method to complement the limitations of visual assessment for whitening efficacy in Asians.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.5-5
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• 2017

Too little and too much water due to climatic events is a significant cause of global food insecurity. Crops are less productive under water-limited conditions and all major crops, with the exception of rice (Oryza sativa), die within a few days of complete submergence. To complement our studies on genes such as SUB1A, (an ERF-VII transcription factor that provides robust submergence tolerance) and AG1 (a TREHALOSE 6-P PHOSPHATASE that promotes establishment of young seedlings underwater), we have retooled INTACT (${\underline{I}}solation$ of ${\underline{N}}uclei$ ${\underline{TA}}gged$ in specific ${\underline{C}}ell$ ${\underline{T}}ypes$) and TRAP (${\underline{T}}ranslating$ ${\underline{R}}ibosome$ ${\underline{A}}ffinity$ ${\underline{P}}urification$) for rice. These technologies enable us to follow dynamics in chromatin, nuclear pre-mRNAs and ribosome-bound mRNAs in meristems and diverse cell types. With these technologies we can better interpret responses to stresses and reestablishment of homeostasis. These include stress acclimation strategies involving changes in metabolism and development, such as dynamics in suberin deposition in sub-epidermal layers of roots that limit water loss under drought and oxygen escape during waterlogging. Our new data uncover dynamic and reversible regulation at multiple levels of gene regulation and provide new insights into processes of stress resilience. Supported by US NSF-PGRP Plasticity (IOS-1238243), Secretome (IOS-1546879) and REU (DBI-146129) grants.

• Journal of the Korean Electrochemical Society
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• v.8 no.1
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• pp.6-11
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• 2005

Direct borohydrides fuel cell (DBFC) was emerged to complement the problem of DMFC's low performance and methanol crossover to the cathode and to apply the fuel cell to portable and mobile devices. In this study, the characteristics of novel catalysts was tested to establish the electrode preparation process of DBFC. Pt black and carbon supported-Pt by paste method were used as the cathode catalysts. Pt black, carbon supported-Au and $AB_5$ alloy were used as the anode catalysts. The characteristics of the electrodes were analyzed by XRD, SEM, EDS. The performance test of single cell using the electrodes were carried out in order to evaluate the electrode performance. In the result, the maximum power output was obtained as 366 mW/mg when using Pt/C as anode and cathode catalysts.

• ALGAE
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• v.28 no.1
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• pp.121-129
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• 2013

Intact phycobilisomes from a wild-type red Chondrus crispus and its vegetatively derived green mutant were isolated by centrifugation through a discontinuous sucrose density gradient. Pigment composition was subsequently characterized by spectrophotometry. Vegetative thalli of the two strains grown together for six months in the laboratory resulted in different pigment profiles. Two pigmented phycobilisome bands appeared in the sucrose gradient of the wild-type alga, a purple coloured one, and a pink one, whereas only a single blue band appeared in the gradient of the green mutant. Spectrophotometric and fluorescence analyses identified the phycobiliprotein composition of the purple band as the typical phycoerythrin-phycocyanin-allophycocyanin complement in the wild-type, but there was no detectable phycoerythrin present in the blue band of the green mutant. Sodium dodecyl sulphate, preparative polyacrylamide gel electrophoresis analysis confirmed the presence of allophycocyanin subunits in all extracts, but firm evidence of an R-phycoerythrin linker polypeptide in the blue band was missing. These results highlight the ability of C. crispus to adapt to a phycoerythrin deficiency by adjusting light harvesting pigment ratios.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.2
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• pp.94-99
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• 2018

Objective: Prompt diagnosis and management are essential for saving the adnexal organs from infarction in cases of ovarian torsion (OT). This study aimed to determine the diagnostic significance of signal peptide, complement C1r/C1s, Uegf, and Bmp1 (CUB), and epidermal growth factor-like domain-containing protein-1 (SCUBE-1) levels in cases of OT, an emergent ischemic condition, and the relationship of SCUBE-1 with oxidative stress parameters. Methods: This prospective study was conducted among 15 OT patients and 20 age- and gravidity-matched healthy women. SCUBE-1 serum concentrations were determined by using enzyme-linked immunosorbent assays. In addition, oxidative stress was evaluated by measuring the serum levels of advanced oxidation protein products (AOPP), ferric reducing ability of plasma (FRAP), and glutathione (GSH). Results: The SCUBE-1 titers were significantly higher in the patients with OT than in the controls (p=0.008). In addition, serum FRAP and GSH levels were significantly lower in the OT patients than in the controls (p<0.001 for both). Serum AOPP levels were higher in the OT patients, but this trend was not statistically significant (p>0.05). Furthermore, there were no correlations between SCUBE-1 levels and age, gravidity, parity, cyst size, and AOPP, FRAP, or GSH levels (p>0.05). Conclusion: We believe that SCUBE-1 may be a promising biomarker for the early diagnosis of OT.