1.Molecular characteristics of ESBLproducing Escherichia coli isolated from chickens with colibacillosis
Journal of Veterinary Science 2022;23(3):e37-
Background:
Avian pathogenic Escherichia coli (APEC) causes colibacillosis, resulting in significant economic losses in the poultry industry.
Objectives:
In this study, the molecular characteristics of two extended-spectrum betalactamase (ESBL)-producing APEC isolates were compared with previously reported ESBLproducing E. coli isolates.
Methods:
The molecular characteristics of E. coli isolates and the genetic environments of the ESBL genes were investigated using whole genome sequencing.
Results:
The two ESBL-producing APEC were classified into the phylogenetic groups C and B1 and ST410 and ST162, respectively. Moreover, the ESBL genes of the two isolates were harbored in different Inc plasmids. The EC1809182 strain, harboring the blaCTX-M-55 gene on the plasmid, exhibited extensive homology to IncFIB (98.4%) and IncFIC(FII) (95.8%). The EC1809191 strain, harboring the blaCTX-M-1 gene, was homologous to IncI1-I (Gamma) (99.3%). All chromosomes carried the multidrug transporter, mdf(A) gene. Mobile genetic elements, adjacent to CTX-M genes, facilitated the dissemination of genes in the two isolates, analogous to other ESBL-producing E. coli isolates.
Conclusions
This study clarifies the transmission dynamics of CTX-M genes and supports strengthened surveillance to prevent the transmission of the antimicrobial-resistant genes to humans via the food chain.
2.Molecular characteristics of Escherichia coli from bulk tank milk in Korea
Journal of Veterinary Science 2022;23(1):e9-
Background:
Escherichia coli, which causes subclinical or clinical mastitis in cattle, is responsible for transmitting antimicrobial resistance via human consumption of raw milk or raw milk products.
Objectives:
The objective of this study was to investigate the molecular characteristics of 183 E. coli from bulk tank milk of five different dairy factories in Korea.
Methods:
The molecular characteristics of E. coli such as serogroup, virulence, antimicrobial resistance, and integron genes were detected using polymerase chain reaction and antimicrobial susceptibility were tested using the disk diffusion test.
Results:
In the distribution of phylogenetic groups, group D was the most prevalent (59.6%) and followed by group B1 (25.1%). The most predominant serogroup was O173 (15.3%), and a total of 46 different serotypes were detected. The virulence gene found most often was fimH (73.2%), and stx1, fimH, incC, fyuA, and iutA genes were significantly higher in isolates of phylogenetic group B1 compared to phylogenetic groups A, B2, and D (p < 0.05). Among 64 E. coli isolates that showed resistance to at least one antimicrobial, the highest resistance rate was observed for tetracyclines (37.5%). All 18 integron-positive E. coli carried the integron class I (int1) gene, and three different gene cassette arrangements, dfrA12+aadA2 (2 isolates), aac(6′)-Ib3+aac(6′)-Ib-cr+aadA4 (2 isolates), and dfrA17+aadA5 (1 isolate) were detected.
Conclusions
These data suggest that the E. coli from bulk tank milk can be an indicator for dissemination of antimicrobial resistance and virulence factors via cross-contamination.
3.Changes in potassium concentration and gene expression in mice fed a high-fat diet.
Junkoo YI ; Rijin KANG ; Zaeyoung RYOO ; Duhak YOON ; Sunghyun KIM ; Myoungok KIM
Journal of Biomedical Research 2015;16(4):165-171
Obesity is a risk factor for various diseases, including cardiovascular disease, diabetes, renal disease, hypertension, cancer, and neural disease. Adipose tissue in animals is important for the mobilization of lipids, milk production, deposition of fat in different depots, and muscle and meat production. Understanding the genetic and physiological causes of metabolic disease is a priority in biomedical genome research. In this study, we examined several variables in mice fed a high-fat diet, including serum composition, body weight, total calorie intake, and differentially expressed genes. Body weight and blood glucose levels were not significantly different between animals fed high-fat and normal diets. However, high-fat diet groups showed reduced calorie and food intakes. Levels of sodium, ionized calcium, glucose, hematocrit, hemoglobin, pH, PCO2, PO2, TCO2 +, HCO3 +, base excess, and SO2 in the blood were not significantly different between mice fed high-fat and normal diets. Serum potassium concentration, however, was lower in mice a high-fat diet. Differentially expressed genes were also compared between the two groups. The purpose of this study was to discover new genes as a result of annealing control primer (ACP) PCR using 20 random primers. Five down regulated genes were identified and three of others were upregulated by high-fat diet. Known genes were excluded from this result. In addition, the relationships among candidate genes and high-fat diet should be investigated according to potassium concentration in the blood. In conclusion, mice fed normal and high-fat diets showed no significant difference in body weight, whereas high-fat diet led to changes in blood composition and differential expression of several genes. These findings may provide a better understanding of the mechanisms underlying the association between obesity and metabolic diseases.
Adipose Tissue
;
Animals
;
Blood Glucose
;
Body Composition
;
Body Weight
;
Calcium
;
Cardiovascular Diseases
;
Diet
;
Diet, High-Fat*
;
Gene Expression*
;
Genome
;
Glucose
;
Hematocrit
;
Hydrogen-Ion Concentration
;
Hypertension
;
Meat Products
;
Metabolic Diseases
;
Mice*
;
Milk
;
Obesity
;
Polymerase Chain Reaction
;
Potassium*
;
Risk Factors
;
Sodium
4.Maternal Depression and Children's Screen Overuse.
Sunghyun PARK ; Hyoung Yoon CHANG ; Eun Jin PARK ; Heejeong YOO ; Woodong JO ; Sung Ju KIM ; Yunmi SHIN
Journal of Korean Medical Science 2018;33(34):e219-
BACKGROUND: It is known that there are various factors associated with children's screen overuse. The aim of this study was to examine the effect of maternal depression on 2–5-year-old children's overuse of various household screen devices. METHODS: Participants were from the Internet-Cohort for Understanding of internet addiction Risk factors/Rescue in Early livelihood (I-CURE) study, an observational prospective cohort study in Korea. Screen time for six types of screen devices (smartphone, television, computer, tablet, video gaming console, and portable gaming console) were assessed by parental questionnaire. Maternal depression was measured by the Korean version of the Beck Depression Inventory II. Logistic regression models were run to determine the association between maternal depression and children's screen overuse. RESULTS: Maternal depression was associated with children's television overuse after adjusting for other factors (odds ratio, 1.954; P = 0.034). Contrary to expectation, the relationship between maternal depression and screen time was not present on other devices such as smartphones, computers and tablets. CONCLUSION: Maternal depression is related with 2–5-year-old children's television overuse. Interventions in maternal depressive symptoms and the associated changes in parent-child relationship can be useful for preventing children's television overuse.
Cohort Studies
;
Computers, Handheld
;
Depression*
;
Family Characteristics
;
Humans
;
Internet
;
Korea
;
Logistic Models
;
Parent-Child Relations
;
Parents
;
Prospective Studies
;
Smartphone
;
Tablets
;
Television
5.Comparative profiling by data-independent acquisition mass spectrometry reveals featured plasma proteins in breast cancer: a pilot study
Kyung-Hwak YOON ; Hyosub CHU ; Hyeonji KIM ; Sunghyun HUH ; Eun-Kyu KIM ; Un-Beom KANG ; Hee-Chul SHIN
Annals of Surgical Treatment and Research 2024;106(4):195-202
Purpose:
Breast cancer is known to be influenced by genetic and environmental factors, and several susceptibility genes have been discovered. Still, the majority of genetic contributors remain unknown. We aimed to analyze the plasma proteome of breast cancer patients in comparison to healthy individuals to identify differences in protein expression profiles and discover novel biomarkers.
Methods:
This pilot study was conducted using bioresources from Seoul National University Bundang Hospital’s Human Bioresource Center. Serum samples from 10 breast cancer patients and 10 healthy controls were obtained. Liquid chromatography-mass spectrometry analysis was performed to identify differentially expressed proteins.
Results:
We identified 891 proteins; 805 were expressed in the breast cancer group and 882 in the control group. Gene set enrichment and differential expression analysis identified 30 upregulated and 100 downregulated proteins in breast cancer. Among these, 10 proteins were selected as potential biomarkers. Three proteins were upregulated in breast cancer patients, including cluster of differentiation 44, eukaryotic translation initiation factor 2-α kinase 3, and fibronectin 1. Seven proteins downregulated in breast cancer patients were also selected: glyceraldehyde-3-phosphate dehydrogenase, α-enolase, heat shock protein member 8, integrin‑linked kinase, tissue inhibitor of metalloproteinases-1, vasodilatorstimulated phosphoprotein, and 14-3-3 protein gamma. All proteins had been previously reported to be related to tumor development and progression.
Conclusion
The findings suggest that plasma proteome profiling can reveal potential diagnostic biomarkers for breast cancer and may contribute to early detection and personalized treatment strategies. A further validation study with a larger sample cohort of breast cancer patients is planned.
6.Therapeutic Extracellular Vesicles from Tonsil-Derived Mesenchymal Stem Cells for the Treatment of Retinal Degenerative Disease
Seung Woo CHOI ; Sooin SEO ; Hye Kyoung HONG ; So Jung YOON ; Minah KIM ; Sunghyun MOON ; Joo Yong LEE ; Jaeseung LIM ; Jong Bum LEE ; Se Joon WOO
Tissue Engineering and Regenerative Medicine 2023;20(6):951-964
BACKGROUND:
Retinal degenerative disease (RDD), one of the most common causes of blindness, is predominantly caused by the gradual death of retinal pigment epithelial cells (RPEs) and photoreceptors due to various causes. Cell-based therapies, such as stem cell implantation, have been developed for the treatment of RDD, but potential risks, including teratogenicity and immune reactions, have hampered their clinical application. Stem cell-derived extracellular vesicles (EVs) have recently emerged as a cell-free alternative therapeutic strategy; however, additional invasiveness and low yield of the stem cell extraction process is problematic.
METHODS:
To overcome these limitations, we developed therapeutic EVs for the treatment of RDD which were extracted from tonsil-derived mesenchymal stem cells obtained from human tonsil tissue discarded as medical waste following tonsillectomy (T-MSC EVs). To verify the biocompatibility and cytoprotective effect of T-MSC EVs, we measured cell viability by co-culture with human RPE without or with toxic all-trans-retinal. To elucidate the cytoprotective mechanism of T-MSC EVs, we performed transcriptome sequencing using RNA extracted from RPEs. The in vivo protective effect of T-MSC EVs was evaluated using Pde6b gene knockout rats as an animal model of retinitis pigmentosa.
RESULTS:
T-MSC EVs showed high biocompatibility and the human pigment epithelial cells were significantly protected in the presence of T-MSC EVs from the toxic effect of all-trans-retinal. In addition, T-MSC EVs showed a dosedependent cell death-delaying effect in real-time quantification of cell death. Transcriptome sequencing analysis revealed that the efficient ability of T-MSC EVs to regulate intracellular oxidative stress may be one of the reasons explaining their excellent cytoprotective effect. Additionally, intravitreally injected T-MSC EVs had an inhibitory effect on the destruction of the outer nuclear layer in the Pde6b gene knockout rat.
CONCLUSIONS
Together, the results of this study indicate the preventive and therapeutic effects of T-MSC EVs during the initiation and development of retinal degeneration, which may be a beneficial alternative for the treatment of RDD.