Abnormal differentiation of regulatory T cells and Th17 cells induced by perinatal bisphenol A exposure in female offspring mice

You‑dan Dong,Liang Gao,Feng‑juan Wu,Ren Lin,Yuan Meng,Li‑hong Jia,Xiao‑fei Wang 대한독성 유전단백체 학회 2020 Molecular & cellular toxicology Vol.16 No.2

Background Bisphenol A (BPA) is an environmental estrogen widely exposed to human beings, and there are more studies on its reproductive toxicity, endocrine disruption and neurobehavioral disorders. Recent few studies have found that BPA has immunotoxicity, and its mechanism is not clear. Therefore, the effects of BPA on immune system have attracted extensive attention. The aim of this study was to investigate the effect and mechanism of perinatal exposure to BPA on regulatory T cells (Treg) and Th17 cells in female offspring mice. Methods Twenty-one pregnant C57BL/6 mice were randomly divided into three groups: a control group, low-dose BPA (0.2 μg/mL) and high-dose BPA (2.0 μg/mL) exposure group. All received BPA exposure via drinking water from gestational day 6 to the end of lactation. Female offspring were fed a normal diet and drinking water for 1 month. The percentages of Treg and Th17 cells, the levels of Foxp3 and RORγt protein and IL-17 and TGF-β from spleen tissue or blood were measured in female offspring. Results The percentage of Treg cells and levels of Foxp3 protein decreased, while the percentage of Th17 cells and levels of RORγt protein increased, which showed a dose–effect relationship. The levels of serum TGF-β were significantly lower and the levels of serum IL-17 were statistically higher in BPA-exposed female offspring compared with controls (P < 0.05 or P < 0.01). But there were no statistical difference in the levels of serum TGF-β and IL-17 between 0.2 μg/mL and 2.0 μg/ mL BPA groups (P > 0.05). Conclusion BPA exposure during pregnancy and lactation could cause abnormal differentiation and function of Treg and Th17 cells in female offspring mice, which was associated with down-regulated Foxp3 and up-regulated RORγt protein, respectively. Our findings indicated that BPA exposure during early development may play an important role in the development of autoimmune diseases later.

Berberine의 항생제 내성 확색포도구균에 대한 항미생물 효과

김강주,차정단,김해경,유현희,유용욱,이동근 대한악안면성형재건외과학회 2002 Maxillofacial Plastic Reconstructive Surgery Vol.24 No.2

Antibiotic-resistant Staphylococcus aureus (S. aureus) emerged in many parts of the world and increased complex clinical problems. Therefore, new agents are needed to treat the antibiotic-resistant S. aureus. Some natural products are candidates of new antibiotic substances. Previous reports showed that the extract of Coptidis Rhizoma and Phellodendri Cortex have antimicrobial effects. The main antibacterial substance of Coptidis Rhizoma and Phellodendri Cortex is berberine. In this study, we examined the antimicrobial activity of berberine to antibiotic-resistant S. aureus. We isolated the 13 strains of antibiotic-resistant S. aureus from the oral cavity of healthy children in a preschool, and investigated the antimicrobial activity of berberine. We examined the effects of berberine on the level of resistance to antibiotic-resistant S. aureus. We observed that the invasion of S. aureus into human gingival fibroblasts was blocked by berberine. Berberine inhibited the growth of antibiotic-resistant S. aureus as a dosw dependent maner. Minimum inhibitory concentration (MIC) of berberine against antibiotic-resistant S. aureus was 50∼100㎍/㎖. The inhibition of S. aureus invasion was depended on the concentration of berberine in human gingival fibroblasts. The MIC of ampicillin against antibiotic-resistant S. aureus was 32㎍/㎖. However, the MIC of ampicillin against antibiotic-resistant S. aureus in the presence of 50㎍/㎖ berberine was 1㎍/㎖. These data indicate that the combination with berberine and β-lactam antibiotics resulted in the synergistic reaction. These results suggest that the berberine may have the antimicrobial activities to antibiotic-resistnat S. aureus, and the mechanism may be the inhibition of growth and intracellular invasion, and alteration of antibiotic-resistance level of antibiotic-resistant S. aureus.

Reconfigurable Flight Control System Design Using Sliding Mode Based Model Following Control Scheme

Cho, Dong-Hyun,Kim, Ki-Seok,Kim, You-Dan The Korean Society for Aeronautical and Space Scie 2003 International Journal of Aeronautical and Space Sc Vol.4 No.1

In this paper, a reconfigurable flight control system is designed by applying the sliding mode control scheme. The sliding mode control method is a nonlinear control method which has been widely used because of its merits such as robustness and flexibility. In the sliding mode controller design, the signum function is usually included, but it causes the undesirable chattering problem. The chattering phenomenon can be avoided by using the saturation function instead of signum function. However, the boundary layer of the sliding surface should be carefully treated because of the use of the saturation function. In contrast to the conventional approaches, the thickness of the boundary layer of our approach does not need to be small. The reachability to the boundary layer is guaranteed by the sliding mode controller. The fault detection and isolation process is operated based on a sliding mode observer. To evaluate the reconfiguration performance, a numerical simulation using six degree-of-freedom aircraft dynamics is performed.

점근적 고유공간 지정법에 의한 제어기 설계에 관한 연구

금동준(Dong-jun Kum),김유단(You-dan Kim) 한국항공우주학회 1993 韓國航空宇宙學會誌 Vol.21 No.1

The Prognostic Value of 18F-Fluorodeoxyglucose PET/CT in the Initial Assessment of Primary Tracheal Malignant Tumor: A Retrospective Study

Shao Dan,Gao Qiang,Cheng You,Du Dong-Yang,Wang Si-Yun,Wang Shu-Xia 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.3

Objective: To investigate the potential value of 18F-fluorodeoxyglucose (FDG) PET/CT in predicting the survival of patients with primary tracheal malignant tumors. Materials and Methods: An analysis of FDG PET/CT findings in 37 primary tracheal malignant tumor patients with a median follow-up period of 43.2 months (range, 10.8–143.2 months) was performed. Cox proportional hazards regression analyses were used to assess the associations between quantitative 18F-FDG PET/CT parameters, other clinic-pathological factors, and overall survival (OS). A risk prognosis model was established according to the independent prognostic factors identified on multivariate analysis. A survival curve determined by the Kaplan-Meier method was used to assess whether the prognosis prediction model could effectively stratify patients with different risks factors. Results: The median survival time of the 37 patients with tracheal tumors was 38.0 months, with a 95% confidence interval of 10.8 to 65.2 months. The 3-year, 5-year and 10-year survival rate were 54.1%, 43.2%, and 16.2%, respectively. The metabolic tumor volume (MTV), total lesion glycolysis (TLG), maximum standardized uptake value, age, pathological type, extension categories, and lymph node stage were included in multivariate analyses. Multivariate analysis showed MTV (p = 0.011), TLG (p = 0.020), pathological type (p = 0.037), and extension categories (p = 0.038) were independent prognostic factors for OS. Additionally, assessment of the survival curve using the Kaplan-Meier method showed that our prognosis prediction model can effectively stratify patients with different risks factors (p < 0.001). Conclusion: This study shows that 18F-FDG PET/CT can predict the survival of patients with primary tracheal malignant tumors. Patients with an MTV > 5.19, a TLG > 16.94 on PET/CT scans, squamous cell carcinoma, and non-E1 were more likely to have a reduced OS.

백스테핑기법과 신경회로망을 이용한 적응 재형상 비행제어법칙

신동호(Dong-Ho Shin),김유단(You-Dan Kim) 제어로봇시스템학회 2003 제어·로봇·시스템학회 논문지 Vol.9 No.4

Fabrication of Biodegradable Polymeric Micro Chambers Encapsulated with Pulverized Drug for Bacteria-Based Microrobots

Byeonghwa Song,Hyung Jung Yoo,Eun-Goo Jeong,Sung Jae Kim,Jong Mo Seo,Tae-You Kim,Dong-Il “Dan” Cho 제어로봇시스템학회 2014 제어로봇시스템학회 국제학술대회 논문집 Vol.2014 No.10

This paper presents a method of fabricating pulverized drug, Lapatinib (Tykerb®), loaded micro chambers made of a biodegradable polymer, poly (ε-caprolactone) (PCL), for bacteria-based microrobots. The PCL is a biodegradable, biocompatible polymer which is approved by the U.S. Food and Drug Administration (FDA) for use in the implantable medical devices. Lapatinib is approved by the U.S. FDA for the treatment of advanced or metastatic breast cancer. In order to realize bacteria-based microrobots, selective bacterial adhesion is necessary which can enhance directional locomotion of the bacteria-based microrobots. The x-ray lithography process can be used for biodegradable polymer micromachining to fabricate structures with various shapes which can be applied for bacteria-based microrobots. A pulverized drug is used because a liquefied drug cannot be used for the x-ray lithography process. To fabricate pulverized Lapatinib loaded micro chambers, the PCL films are prepared by the solvent casting method and lamination process. Lapatinib is encapsulated between the PCL films by the screen printing method. The x-ray lithography process is then used for fabrication of micro chambers. The fabrication results indicate that the proposed method is appropriate for fabrication of biodegradable polymeric micro chambers encapsulated with the pulverized drug for bacteria-based microrobots.

Surface Energy Modification Method Using X-ray Synchrotron Irradiation for Controlling Bacterial Adhesion on Biodegradable-Polymer Structures for Bacteria-Flagellated Microrobots

Hyung Jung Yoo,Sangmin Lee,Jaehyun Ahn,Sungjin Oh,Byeonghwa Song,Sung Jae Kim,Jong-Mo Seo,Tae-You Kim,Dong-il “Dan” Cho 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

Bacteria-based biomedical microrobots have been proposed to achieve effective localized drug delivery. To enhance a directional locomotion of bacteria-attached microsystem, structures with selective bacterial adhesion are necessary. Having different surface morphologies of microstructures is beneficial for selective attachments of bacteria. In this paper, a surface energy modification method for controlling bacterial adhesion on biodegradable-polymer structures is presented. This is achieved by controlling exposed doses of x-ray synchrotron irradiation. To calculate the x-ray exposure time for varying the surface morphology of the biodegradable polymeric devices, the equation for exposed dose is derived. The contact angles of different surfaces are measured, and the corresponding surface energies are calculated to verify the modification of the surface morphology. As a result, the surface energy increases with the increment of the exposed dose to the biodegradable-polymer. The developed surface energy modification method is suitable for modifying the polymeric surface without additional physical/chemical treatments. The fabricated cubic structures with different surface morphologies can be used for effectively flagellating bacteria on selective surfaces for directional locomotion.