Health Risks Associated with Methylmercury Exposure and Molecular Toxicological Approaches for Its Study

Gi-Wook Hwang 한국환경과학회 2019 한국환경과학회 학술발표회 발표논문집 Vol.2019 No.11

Associations of the Polymorphisms in <i>DHRS4</i>, <i>SERPING1</i>, and <i>APOR</i> Genes with Postmortem pH in Berkshire Pigs

Hwang, Jung Hye,An, Sang Mi,Kwon, Seul Gi,Park, Da Hye,Kim, Tae Wan,Kang, Deok Gyung,Yu, Go Eun,Kim, Il-Suk,Park, Hwa Chun,Ha, Jeongim,Kim, Chul Wook Informa UK (TaylorFrancis) 2017 Animal biotechnology Vol.28 No.4

<P>Postmortem pH is a main factor influencing the meat quality in pigs. This study investigated the association of postmortem pH with single-nucleotide polymorphisms (SNPs) in the fourth member of the short-chain dehydrogenase/reductase family (DHRS4), the first member of serpin peptidase inhibitor, clade G (complement inhibitor) (SERPING1), and the apolipoprotein R precursor (APOR) genes in Berkshire pigs. The study included 437 pigs, and genotyping was conducted using the GoldenGate Assay (Illumina, San Diego, CA, USA). DHRS4, SERPING1, and APOR polymorphisms were significantly associated with pH(45) or pH(24) (p<0.05). SERPING1 was also statistically significantly associated with water holding capacity (p<0.05), which is closely associated with postmortem pH. These results suggest that SNPs in the DHRS4, SERPING1, and APOR genes have potential for use as genetic markers for the meat quality in pigs.</P>

Increased Risk of Bacterial Infection in Cirrhotic Patients with Acute Variceal Bleeding Who Were Treated with Prophylactic Rifaximin

( Wook Hyun Yeo ),( Eileen L. Yoon ),( Hyung Gi Bae ),( Yu Ri Hwang ),( Seong Eun Park ),( Jong Ho Lee ),( Ji Young Park ),( Jung Min Choi ),( Tae Joo Jeon ),( Won Chang Shin ),( Won-choong Choi ) 대한간학회 2016 춘·추계 학술대회 (KASL) Vol.2016 No.1

Aims: Prophylactic antibiotic use for spontaneous bacterial peritonitis or hepatic encephalopathy is common in decompensated cirrhotic patients with low level of ascitic protein and poor liver function. There is controversy whether prolonged antibiotic use is related with increased risk of bacterial infection other than SBP. We investigated whether the prophylactic use of rifaximin is associated with increased infection risk in cirrhotic patients. Methods: We reviewed the charts of 160 cirrhotic patients with acute variceal bleeding between 2009 and 2015 and compared the use rate of prophylactic rifaximin in infection group and non-infection group within 1, 3, and 6 months off-treatment. Results: Among 160 patients, 105 patients developed bacterial infection within a year follow-up. Ironically the rate of rifaximin use was higher in the infection group than non-infection group in 1, 3, 6 months off-treatment (p<0.001). MELD score were similar in both groups of patients. Prophylactic rifaximin was the only independent predictor of infection in 1 and 3 months off-treatment and odd ratios (OR) were 8.00/5.00 for 1month (p<0.001)/3months (p<0.001). Thrombocytopenia (OR 0.992, p=0.009) and rifaximin use (OR 2.963, p=0.002) were predictors of infection in 6 months off-treatment. However, types of infection were not significantly different between two groups. Conclusions: Prophylactic use of rifaximin after intravenous antibiotics in cirrhotic patients with acute variceal bleeding increased the risk of bacterial infections. Further study about gains & losses of prophylactic rifaximin are needed, especially in patients with various types of developed infection.

Investigation of Cure Kinetics and Storage Stability of the o-Cresol Novolac Epoxy Nanocomposites with Pre-intercalated Phenolic Hardeners

Hwang, Tae-Yong,Lee, Jae-Wook,Lee, Sang-Min,Nam, Gi-Joon The Polymer Society of Korea 2009 Macromolecular Research Vol.17 No.2

The cure kinetics of the epoxy-layered, silicate nanocomposites were studied by differential scanning calorimetry under isothermal and dynamic conditions. The materials used in this study were o-cresol novolac epoxy resin and phenol novolac hardener, with organically modified layered silicates. Various kinetic parameters, including the reaction order, activation energy, and kinetic rate constants, were investigated, and the storage stability of the epoxy-layered silicate nanocomposites was measured. To synthesize the epoxy-layered silicate nanocomposites, the phenolic hardener underwent pre-intercalation by layered silicate. From the cure kinetics analyses, the organically modified layered silicate decreased the activation energy during cure reaction in the epoxy/phenolic hardener system. In addition, the storage stability of the nanocomposite with the pre-intercalated phenolic hardener was significantly increased compared to that of the nanocomposite with direct mixing of epoxy, phenolic hardener, and layered silicate. This was due to the protective effect of the reaction between onium ions and epoxide groups.

Molecular characterization of porcine <i>PGM1</i> gene associated with meat quality traits

Hwang, Jung Hye,Kwon, Seul Gi,Park, Da Hye,Kim, Tae Wan,Kang, Deok Gyeong,Ha, Jeongim,Kim, Sam Woong,Kim, Chul Wook Canadian Science Publishing 2015 Canadian journal of animal science Vol.95 No.1

<P> Hwang, J. H., Kwon, S. G., Park, D. H., Kim, T. W., Kang, D. G., Ha, J., Kim, S. W. and Kim, C. W. 2015. Molecular characterization of porcine PGM1 gene associated with meat quality traits. Can. J. Anim. Sci. 95: 31-36. The PGM1 gene from four porcine breeds (Berkshire, Duroc, Landrace, and Yorkshire) is highly expressed in liver tissue at the transcriptional level. Single nucleotide polymorphisms (SNPs) of PGM1 were examined to analyze association with increased expression of PGM1 gene in the Berkshire liver. A Leu525 synonymous SNP of Chr6:137174682A@@>@@G (c.1575A@@>@@G) was identified and showed significant (P@@<@@0.05) differences to backfat thickness, drip loss, protein content, fat content, Warner-Bratzler shear force, and post-mortem pH24h. Therefore, it is concluded that PGM1 synonymous SNP is an important factor regulating meat quality. </P>

Physicochemical Components and Antioxidant Activities of Daebong Persimmon (Diospyros kaki cv. Hachiya) Peel Vinegars

Gi-Un Seong,In-Wook Hwang,Shin-Kyo Chung 경북대학교 농업생명과학대학 2013 Current Research on Agriculture and Life Sciences Vol.31 No.4

To evaluate utilization of persimmon peels as novel bio-materials, the general composition and antioxidant activities of Daebong persimmon vinegar (DPV), Daebong persimmon peel vinegar (DPPV) and commercial persimmon vinegar (CPV) were investigated. The pH of DPPV had slightly higher than that of other vinegars. The titratable acidities of vinegars were 3.24% (DPV), 2.77% (DPPV) and 7.78% (CPV), respectively. The reducing sugar contents showed that DPV had slightly higher than that of other vinegars. The browning degree of DPV was lower than CPV in contrast to the turbidity. The results of Hunter’s color value have showed that overall values of CPV had significantly higher than DPPV and DPV. The total phenolic contents of DPV and CPV were 19.49 and 17.13 mg/100g GAE, respectively. The total flavonoid contents of DPPV (8.04 mg/100g CE) were two fold higher than that of DPV (3.85 mg/100g CE). The antioxidant activities, by DPPH and FRAP assays, of DPV showed stronger than those of other vinegars. Free sugars were mainly composed of fructose and glucose. Organic acids were presented in the order acetic acid, succinic acid, malic acid, tartaric acid, citric acid and oxalic acid. These results suggest that the Daebong persimmon peels could be utilized for vinegar production as a health-benefit material.

아조염료의 전기분해에 대한 반응파라미터의 측정

황영기,방시욱 慶南大學校 附設 工業技術硏究所 1998 硏究論文集 Vol.15 No.3

Carmine-6B 아조염료 수용약을 양극산화시키는 전기분해반응에서 부반응이 없는 최소운전전압은 1.2V로, 산소발생에 따른 부가적인 산화작용을 고려한 최적운전전압은 20∼25V로 각각 조사되었다. 초기속도법으로 구한 분해반응치수는 0.68로 측정되었으며 반응속도는 전압상승에 따라 0.5승에 비례하였다. 물질전달계수는 pH에 무관하고 교반속도의 ⅓승에 비례 증가하였다. Decomposition of Carmine-6B azo dye has been performed by electrochemical oxidation. Minimum voltage for the reaction was found to be 1.2V. Oxygen evoluted on anode effected on the decomposition at the cell voltage as high as 20V or 25V. Initial reaction rate depended on both initial concentration with 0.68th order and cell voltage with 0.5th order. Mass transfer coefficient of azo dye was independent on pH of solution, but it was in proportion to its agitating speed by one third power .

Thermally driven homonuclear-stacking phase of MoS₂ through desulfurization

Hwang, Young Hun,Yun, Won Seok,Cha, Gi-Beom,Hong, Soon Cheol,Han, Sang Wook The Royal Society of Chemistry 2019 Nanoscale Vol.11 No.23

<P>Engineering phase transitions or finding new polymorphs offers tremendous opportunities for developing functional materials. We reveal that the thermally driven desulfurization of single-crystalline MoS2 samples improves transport properties by reducing the band gap and further induces metallization. Semi-desulfurization, <I>i.e.</I>, removal of the topmost S layer, results in the placement of the exposed Mo layers directly on top of the following sub-layers, together with the bottom S layer of the top layer. This homonuclear (AA) stacking derived from the AA′ stacking of the hexagonal (2H) phase is retained even after further desulfurization of the remaining bottom S layer, <I>i.e.</I>, full desulfurization of the top layer. Our findings fundamentally explain why the 2H phase of TMDs is characterized by AA′ stacking.</P>

Postmortem mRNA Expression Patterns in Left Ventricular Myocardial Tissues and Their Implications for Forensic Diagnosis of Sudden Cardiac Death

Son, Gi Hoon,Park, Seong Hwan,Kim, Yunmi,Kim, Ji Yeon,Kim, Jin Wook,Chung, Sooyoung,Kim, Yu-Hoon,Kim, Hyun,Hwang, Juck-Joon,Seo, Joong-Seok Korean Society for Molecular and Cellular Biology 2014 Molecules and cells Vol.37 No.3

Sudden cardiac death (SCD), which is primarily caused by lethal heart disorders resulting in structural and arrhythmogenic abnormalities, is one of the prevalent modes of death in most developed countries. Myocardial ischemia, mainly due to coronary artery disease, is the most common type of heart disease leading to SCD. However, postmortem diagnosis of SCD is frequently complicated by obscure histological evidence. Here, we show that certain mRNA species, namely those encoding hemoglobin A1/2 and B (Hba1/2 and Hbb, respectively) as well as pyruvate dehydrogenase kinase 4 (Pdk4), exhibit distinct postmortem expression patterns in the left ventricular free wall of SCD subjects when compared with their expression patterns in the corresponding tissues from control subjects with non-cardiac causes of death. Hba1/2 and Hbb mRNA expression levels were higher in ischemic SCD cases with acute myocardial infarction or ischemic heart disease without recent infarction, and even in cardiac death subjects without apparent pathological signs of heart injuries, than control subjects. By contrast, Pdk4 mRNA was expressed at lower levels in SCD subjects. In conclusion, we found that altered myocardial Hba1/2, Hbb, and Pdk4 mRNA expression patterns can be employed as molecular signatures of fatal cardiac dysfunction to forensically implicate SCD as the primary cause of death.

결구배추 잎의 이화학적 성분 조성

성기운(Gi-Un Seong),황인욱(In-Wook Hwang),정신교(Shin-Kyo Chung) 한국식품영양과학회 2016 한국식품영양과학회지 Vol.45 No.6

김치용 결구배추를 겉잎(L1), 중잎(L2), 속잎(L3)으로 세 등분하여 부위별로 일반성분을 포함한 이화학적인 성분을 측정하여 비교하였다. 조단백질 및 조지방 함량은 겉잎(L1)이 높았고, 조회분 및 탄수화물 함량은 속잎(L3)이 높았다(P<0.05). 열량은 24.5~26.5 kcal/100 g이었고 부위별로 유의적인 차이가 없었으며, 총식이섬유는 겉잎(L1)이 가장 높았다(P<0.05). 유리당은 fructose, glucose, sucrose가 확인되었으며, 속잎(L3)에서 fructose 및 glucose 함량이 높았다(P<0.05). 유기산은 citric acid, malic acid, succinic acid가 검출되었으며, citric acid와 malic acid 함량은 속잎(L3)이 높았고 succinic acid는 겉잎(L1)이 높았다(P<0.05). 총유리 아미노산의 30% 이상을 차지하는 glutamic acid 함량은 속잎(L3)에서 높았으며, γ-aminobutyric acid의 함량은 겉잎(L1)이 가장 높았다(P<0.05). 결구배추 잎의 주요 미네랄 성분은 K, Na, Ca, Mg이며, 이 중 K의 함량이 가장 높았다. 총미네랄 함량은 겉잎(L1)이 가장 높았다(P<0.05). 결구배추 잎은 부위에 따라 이화학적 성분 조성이 다른 특성을 가지므로 신선편의 식재료로서 활용성이 더욱 증대될 수 있을 것으로 생각한다. To increase the consumption of head-type kimchi cabbage leaves as fresh food ingredients, the physicochemical composition was investigated depending on leaf parts. Kimchi cabbage leaves were divided into three portions, such as outer (L1), mid (L2), and inner (L3), and their proximate compositions were determined along with dietary fiber, free sugar, organic acid, free amino acid, and mineral contents. Contents of moisture, crude protein, and crude fat were highest in L1, whereas contents of crude ash and carbohydrate were highest in L3 (P<0.05). Calories ranged 24.5∼26.5 kcal/100 g with no significant difference among leaf parts, and dietary fiber content of L1 was highest (P<0.05). Fructose, glucose, and sucrose contents were highest in L3 (P<0.05). Citric acid, malic acid, and succinic acid were detected, and contents of citric acid and malic acid were highest in L3, in contrast, succinic acid was highest in L1 (P<0.05). Glutamic acid, constituting over 30% of the total free amino acid contents, was highest in L3, whereas γ-aminobutyric acid contents were highest in L1 (P<0.05). K, Na, Ca, and Mg were the major minerals in head-type kimchi cabbage, and their contents showed no significant differences (P<0.05). It can be proposed that marketing of head-type kimchi cabbage as a fresh-cut vegetable could be enhanced due to the different quality characteristics of its leaf parts.