Experiences and Perceptions of Gender Discrimination and Equality among Korean Surgeons: Results of a Survey of the Korean Surgical Society.

BACKGROUND: Previous studies that have focused on the challenges faced by female surgeons, such as the gender pay gap, gender biases, lower likelihood of promotion, and gender differences in the perception of discrimination against women, are reviewed. A more comprehensive understanding of explicit and implicit gender discrimination and experiences and perceptions of discrimination is needed. This study aims to determine the current prevalence and degree of gender discrimination in the Korean Surgical Society and to compare the experiences and perceptions of gender discrimination between male and female surgeons. METHODS: We analyzed 400 responses from a survey sent to all members of the Korean Surgical Society. This electronic survey included 16 items on experiences of gender discrimination and 17 items on perceptions of gender discrimination. We conducted χ² tests and binary logistic regression on the data regarding these experiences and perceptions of gender discrimination. RESULTS: Adjusted analyses found that female surgeons were more likely to experience gender discrimination than their male counterparts across all categories of discrimination. Further, adjusted analyses showed that female surgeons were more likely to confirm the presence of gender discrimination than male surgeons. CONCLUSION: Female surgeons were more likely to experience implicit and explicit gender biases and discrimination throughout all stages of their career progression. We also discovered significant gender differences in the perception of gender discrimination, as well as the experience of it. Changing the male-dominated culture and raising awareness of gender biases and discrimination among male surgeons are crucial steps toward addressing gender discrimination in surgery.

Alteration of Microbiome Profile by D-Allulose in Amelioration of High-Fat-Diet-Induced Obesity in Mice.

Recently, there has been a global shift in diet towards an increased intake of energy-dense foods that are high in sugars. D-allulose has received attention as a sugar substitute and has been reported as one of the anti-obesity food components; however, its correlation with the intestinal microbial community is not yet completely understood. Thirty-six C57BL/6J mice were divided in to four dietary groups and fed a normal diet (ND), a high-fat diet (HFD, 20% fat, 1% cholesterol, w/w), and a HFD with 5% erythritol (ERY) and D-allulose (ALL) supplement for 16 weeks. A pair-feeding approach was used so that all groups receiving the high-fat diet would have the same calorie intake. As a result, body weight and body fat mass in the ALL group were significantly decreased toward the level of the normal group with a simultaneous decrease in plasma leptin and resistin. Fecal short-chain fatty acid (SCFA) production analysis revealed that ALL induced elevated total SCFA production compared to the other groups. Also, ALL supplement induced the change in the microbial community that could be responsible for improving the obesity based on 16S rRNA gene sequence analysis, and ALL significantly increased the energy expenditure in Day(6a.m to 6pm). Taken together, our findings suggest that 5% dietary ALL led to an improvement in HFD-induced obesity by altering the microbiome community.

Role of Synbiotics Containing d-Allulose in the Alteration of Body Fat and Hepatic Lipids in Diet-Induced Obese Mice.

The effects of allulose and two probiotic species on diet-induced obese (DIO) mice were investigated. Lactobacillus sakei LS03 (108 cfu/day) and Leuconostoc kimchii GJ2 (108 cfu/day) were used as probiotics, and allulose (AL) as a prebiotic. The synergistic effect of prebiotics and probiotics in improving obesity was evaluated. Orally fed Lactobacillus sakei LS03 (LS) or Leuconostoc kimchii GJ2 (GJ), significantly decreased hepatic triglyceride (TG) and fatty acid (FA) compared to the high-fat diet (HFD) control. AL markedly decreased visceral adiposity and pro-inflammatory adipokines (leptin and resistin) and cytokines (IL-6 and IL-1ß) as well as hepatic TG and FA. In addition, AL exerted synergic effects with probiotics (LS and/or GJ) on the reduction of visceral white adipose tissue (WAT), associated with a decreased leptin: adiponectin ratio. There was no significant differences between the AL-SL and AL group, allulose and GJ combination (AL-GJ) was more effective than allulose in improving dyslipidemia, and decreasing WAT weight and hepatic FA, suggesting allulose may act as a favorable prebiotic for GJ supplement than LS. Combination of allulose with LS and GJ supplementation (AL-LSGJ) was the most effective for improving obesity related complications among the synbiotics groups containing allulose. In conclusion, this study demonstrated that the synbiotic mixture with allulose was more effective in suppressing diet-induced obese (DIO) and its complications via the regulation of lipid metabolism, than the probiotics or allulose alone, suggesting allulose may act as a prebiotic for the two probiotics tested in the study. This new synbiotic mixture with allulose may help ameliorate the deleterious effects of diet-induced obesity and contribute to the growth of the food industry.

Study on Ion-Conducting Properties of Ionic Liquid Containing Carbonate Electrolytes Against Carbon Electrode.

The ionic performances for the mixture of ethylene carbonate (EC) and dimethylcarbonate (DMC) were investigated for supercapacitor electrolyte. The usage of ethylene carbonate (EC) and dimethylcarbonate (DMC) as organic solvent could solve some problems of acetonitrile (AN). The general aim of present paper is compare to properties of electrochemical properties based on two mixed organic electrolytes. The ionic conductivity, viscosity, and electrochemical performances of EC/DMC+0.1 M TEABF4 mixtures were determined. The ionic conductivity of the electrolytes was measured by AC impedance, and the capacitative performances of the electrolytes were evaluated by using cyclic voltammetry.

Induction of interleukin-1 beta (IL-1ß) is a critical component of lung inflammation during influenza A (H1N1) virus infection.

Cytokine storm during influenza virus infection is recognized as a predictor of morbidity and mortality. To verify the cellular effects of influenza-induced cytokines in primary normal lung cells, human pulmonary microvascular endothelial cells (HMVECs) and lung fibroblast cells (MRC-5 cells) were infected with influenza virus H1N1. H1N1 infection induced the transcription of various genes encoding cytokines and chemokines such as interleukin-1 beta (IL-1ß), IL-6, IL-8, IL-12A, tumor necrosis factor alpha (TNF-α), and chemokine (C-C motif) ligand 5 (CCL5) in both endothelial cells and lung fibroblasts. Among them, IL-1ß induction by influenza infection increased the inflammation of lung cells; conversely, blockade of IL-1ß signals with an IL-1ß receptor antagonist or a neutralizing antibody alleviated influenza-driven inflammation. In conclusion, these data suggest that secreted IL-1ß by the endothelial cells contributes to influenza-induced inflammation, and blockade of IL-1ß signals is a potential treatment or therapeutic target for influenza-induced inflammation.

Detection of single-base mutation in RNA using T4 RNA ligase-based nick-joining or DNAzyme-based nick-generation.

A single nucleotide polymorphism (SNP) is a common genetic variation when a single nucleotide differs between members of a species or paired chromosome. Due to its association with disease susceptibility and drug resistance, SNP detection is of great value in studying the variation in drug responses. Here we present two quantitative SNP detection methods for a single-base mismatch in RNA, based on nick-joining and nick-generating activities of T4 RNA ligase and DNAzyme, respectively. T4 RNA ligase successfully discriminated a one-base mismatch in the ligation junction, and the designed DNAzyme cleaved RNA by discerning a single-base mismatch in the cleaving site.

Oligodeoxyribozymes that cleave beta-catenin messenger RNA inhibit growth of colon cancer cells via reduction of beta-catenin response transcription.

Abnormal regulation of Wnt/beta-catenin signaling followed by increased levels of the beta-catenin protein have been identified in enhanced cellular proliferation and development of colon polyps and cancers. To inhibit beta-catenin gene expression in colon cancer cells, RNA-cleaving oligodeoxyribozyme (DNAzyme) was employed to destroy the beta-catenin mRNA. We designed a strategy to identify the cleavage sites in beta-catenin RNA with a pool of random sequences from a DNAzyme library and identified four potential DNAzyme-working sites. DNAzymes were constructed for the selected target sites and were tested for the ability to cleave beta-catenin RNA. When introduced into the cells, the selected DNAzymes decreased the expression of beta-catenin significantly as well as its downstream gene, cyclin D1. Additionally, we designed short hairpin RNA that targets the same cleavage site for the selected DNAzyme. The designed short hairpin RNA also inhibited beta-catenin gene expression in colon cancer cells. Our studies show that RNA-cleaving DNAzymes and RNA interference targeted to beta-catenin significantly reduced beta-catenin-dependent gene expression, resulting in inhibition of colon cancer cell growth. These results indicate that the functional antisense oligonucleotides directed against beta-catenin might have potential as a therapeutic intervention to treat colon cancer.

Characterization of microbial community during Asian dust events in Korea.

An Asian dust event, also sometimes known as a Yellow Sand event, is a seasonal meteorological phenomenon affecting East Asia, typically in the early spring. Because of the significant ecological and health effects of these events on East Asia, and the large amount of dust that is transported from the desert in China to Korea and Japan, these events have been receiving increased attention. It is likely that these storms often provide long-range transport to various microorganisms. However, despite a certain level of attention to the chemical analysis of these storms, microbiological studies of Yellow Sand dust have been scarce. We collected a total of 30 microbiological air samples using a PM(2.5) cyclone sampler in Seoul, Korea from April 2007 to March 2008. Six of these samples were collected during Yellow Sand events, while 24 were from non-Yellow Sand events. Chemical analysis was performed on the samples using a thermal-optical transmittance (TOT) method. Total nucleic acids were also extracted, and the 16S rDNA was amplified by PCR and analyzed by denaturing gradient gel electrophoresis (DGGE). Dendrogram analysis, based on DGGE, indicated that the microbial profiles from the Yellow Sand were distinctive from those of the non-Yellow Sand samples. Microorganisms identified in Yellow Sand samples included Aquabacterium sp., Flavobacteriales bacterium sp., Prevotellaceae bacterium sp., and others, whereas microorganisms in non-Yellow Sand samples included Propionibacterium sp., Bacillus sp., Acinetobacter sp., and others. These results suggest that, as a result of Yellow Sand events, humans in the affected regions are exposed to communities of microorganisms that might cause various adverse health effects.

Expression of heat shock protein 105 and 70 in malignant melanoma and benign melanocytic nevi.

BACKGROUND: Heat shock proteins (HSPs) restore immature proteins or denatured proteins, thus protecting cells. Also, the expression of some HSPs is elevated substantially in malignant tumors, but the expression of HSPs in association with melanoma has yet to be studied. Therefore, we examined the expression patterns of HSP 70 and 105 in melanoma, benign melanocytic nevi and normal human skin. METHODS: Two specimens of malignant melanoma, two of benign melanocytic nevi and six of normal human skin were analyzed using Western blot analysis for expression of HSP 70 and 105. In another set, 16 specimens of malignant melanoma, 24 of benign melanocytic nevi and eight of normal human skin were analyzed for the expression of HSP 105 using immunohistochemical studies. RESULTS: The Western blot analysis showed that HSP 70 was overexpressed in all three types. But, the HSP 105 was hardly expressed in normal human skin and benign melanocytic nevi. However, in malignant melanoma, the HSP 105 was overexpressed, and immunohistochemical examination of HSP 105 showed a result similar to that of Western blot analysis. CONCLUSIONS: In our study, HSP 105 is thought to be a more relevant tumor-associated antigen in malignant melanoma than is HSP 70.

Design and kinetic analysis of hammerhead ribozyme and DNAzyme that specifically cleave TEL-AML1 chimeric mRNA.

In order to develop the oligonucleotides to abolish an expression of TEL-AML1 chimeric RNA, which is a genetic aberration that causes the acute lymphoblastic leukemia (ALL), hammerhead ribozymes and deoxyoligoribozymes that can specifically cleave TEL-AML1 fusion RNA were designed. Constructs of the deoxyribozyme with an asymmetric substrate binding arm (Dz26) and the hammerhead ribozyme with a 4nt-bulged substrate binding arm in the stem III (buRz28) were able to cleave TEL-AML1 chimeric RNA specifically at sites close to the junction in vitro, without cleaving the normal TEL and AML1 RNA. Single-turnover kinetic analysis under enzyme-excess condition revealed that the buRz28 is superior to the Dz26 in terms of substrate binding and RNA-cleavage. In conjunction with current progress in a gene-delivery technology, the designed oligonucleotides that specifically cleave the TEL-AML1 chimeric mRNA are hoped to be applicable for the treatment of ALL in vivo.

Replication of an RNA ligase ribozyme under alternating temperature condition.

Self-replication process of the RNA ligase ribozyme molecules was investigated by using the modified RNA ligase ribozyme under alternating temperature condition that enhances turnover rate of the RNA ligation reaction. In our experiment, the RNA ligase ribozyme system mainly undergoes a cross-catalytic replication process, in which two ribozymes catalyze each other's synthesis from a total of four RNA substrates under alternating temperature condition, resulting in time-dependent accumulation of additional copies of the starting ribozymes in a reaction mixture. The present study demonstrates that cross-catalytic replication in nucleic acids system can be efficiently devised under the alternating temperature condition.

Expression of glucocorticoid receptor mRNAs in glucocorticoid-resistant nasal polyps.

Glucocorticoids (GCs) are the most effective group of medications available to treat inflammation. Although most patients with inflammation respond to GC, a small group of patients exhibit persistent GC-resistance with prolonged inflammation. Previously, it was proposed that the GC-resistance is caused by low amount of human GC receptor (hGRalpha) and/or excessive presence of a GC receptor isoform, hGRbeta that was generated from alternative splicing of the hGR message. We have tested this hypothesis by investigating correlation between the expression pattern of hGR mRNAs in patients with inflammatory nasal polyps and the effectiveness of GC treatment.? We have performed reverse transcription PCR analysis of mRNAs coding each hGRalpha and hGRbeta in nasal tissues.? hGRalpha mRNA was more expressed in patients with nasal polyps than in normal subjects. However, the elevated hGRalphamRNA expression was decreased after GC treatment. Compared with hGRalpha mRNA expression, level of hGRbeta mRNA expression was very low in all groups. In patients, hGRbetamRNA was expressed at a similar level regardless of GC efficacy, indicating that there is no correlation between the GC sensitivity and the expression level of hGRbeta mRNA. Thus, persistent GC-resistance is not associated with low expression of hGRa or over- expression of hGRbeta.