Alpha-Hemolysin from Staphylococcus aureus Obstructs Yeast-Hyphae Switching and Diminishes Pathogenicity in Candida albicans

Yu Xiaoyu,Mao Yinhe,Li Guangbo,Wu Xianwei,Xuan Qiankun,Yang Simin,Chen Xiaoqing,Cao Qi,Guo Jian,Guo Jinhu,Wu Wenjuan 한국미생물학회 2023 The journal of microbiology Vol.61 No.2

The use of antibiotics can disrupt the body’s natural balance and increase the susteptibility of patients towards fungal infections. Candida albicans is a dimorphic opportunistic fungal pathogen with niches similar to those of bacteria. Our aim was to study the interaction between this pathogen and bacteria to facilitate the control of C. albicans infection. Alpha-hemolysin (Hla), a protein secreted from Staphylococcus aureus, causes cell wall damage and impedes the yeast–hyphae transition in C. albicans. Mechanistically, Hla stimulation triggered the formation of reactive oxygen species that damaged the cell wall and mitochondria of C. albicans. The cell cycle was arrested in the G0/G1 phase, CDC42 was downregulated, and Ywp1 was upregulated, disrupting yeast hyphae switching. Subsequently, hyphae development was inhibited. In mouse models, C. albicans pretreated with Hla reduced the C. albicans burden in skin and vaginal mucosal infections, suggesting that S. aureus Hla can inhibit hyphal development and reduce the pathogenicity of candidiasis in vivo.

American ginseng significantly reduced the progression of high-fat-diet-enhanced colon carcinogenesis in Apc^Min/+ mice

Yu, Chunhao,Wen, Xiao-Dong,Zhang, Zhiyu,Zhang, Chun-Feng,Wu, Xiaohui,He, Xin,Liao, Yang,Wu, Ningning,Wang, Chong-Zhi,Du, Wei,He, Tong-Chuan,Yuan, Chun-Su The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.3

Background: Colorectal cancer (CRC) is a leading cause of death worldwide. Chronic gut inflammation is recognized as a risk factor for tumor development, including CRC. American ginseng is a very commonly used ginseng species in the West. Methods: A genetically engineered $Apc^{Min/+}$ mouse model was used in this study. We analyzed the saponin composition of American ginseng used in this project, and evaluated its effects on the progression of high-fat-diet-enhanced CRC carcinogenesis. Results: After oral ginseng administration (10-20 mg/kg/d for up to 32 wk), experimental data showed that, compared with the untreated mice, ginseng very significantly reduced tumor initiation and progression in both the small intestine (including the proximal end, middle end, and distal end) and the colon (all p < 0.01). This tumor number reduction was more obvious in those mice treated with a low dose of ginseng. The tumor multiplicity data were supported by body weight changes and gut tissue histology examinations. In addition, quantitative real-time polymerase chain reaction analysis showed that compared with the untreated group, ginseng very significantly reduced the gene expression of inflammatory cytokines, including interleukin-$1{\alpha}$ (IL-$1{\alpha}$), IL-$1{\beta}$, IL-6, tumor necrosis factor-${\alpha}$, granulocyte-colony stimulating factor, and granulocyte-macrophage colony-stimulating factor in both the small intestine and the colon (all p < 0.01). Conclusion: Further studies are needed to link our observed effects to the actions of the gut microbiome in converting the parent ginsenosides to bioactive ginseng metabolites. Our data suggest that American ginseng may have potential value in CRC chemoprevention.

From Identity to Economy

Wu Yu-Shan 동아시아재단 2013 Global Asia Vol.8 No.1

Computed tomographic analysis of maxillary sinus anatomy relevant to sinus lift procedures in edentulous ridges in Taiwanese patients

Yu, Shun-Jen,Lee, Yi-Hao,Lin, Ching-Ping,Wu, Aaron Yu-Jen Korean Academy of Periodontology 2019 Journal of Periodontal & Implant Science Vol.49 No.4

Purpose: To analyze the maxillary sinus anatomy over edentulous ridges in the bilateral posterior maxillary area in Taiwanese patients using cone-beam computed tomography (CBCT). Methods: In total, 101 anatomical sites from 61 patients, including 32 premolar and 69 molar regions, were analyzed using CBCT. Measurements were made of the width and height of edentulous ridges, the thickness of the lateral wall of the maxillary sinus, and the presence of a sinus septum and the posterior superior alveolar artery (PSAA). A statistical analysis of the measurements was performed, and correlations among the measurements were assessed. Results: The average ridge width was $10.26{\pm}3.16mm$, with a significantly greater ridge width in the second molar region than in the premolar region. The mean residual ridge height was $8.55{\pm}4.09mm$, and ridge height showed an opposite trend from ridge width for the premolar and molar regions. A sinus septum was present at 5.9% of the sites, and the PSAA was observed in 24.5%. The average thickness of the lateral wall of the maxillary sinus was $2.08{\pm}0.94mm$, with no significant difference between the tooth position and lateral wall thickness. Conclusions: This study presents the anatomical features of the maxillary sinus, which should be considered in sinus lift procedures for implant placement, in the Taiwanese population. The use of CBCT is recommended to avoid intraoperative complications.

Numerical Investigation of Flow Characteristics in a Viscous Damping System with Symmetrical Hydraulic Cylinders

Yu-Ting Wu,Zhen Qin,Amre Eizad,Sung-Ki Lyu,Choon-Man Lee 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.4

Hydraulic dampers are widely applied due to their characteristics of absorbing huge impact energy, stable and reliable working performance, and easy on-demand design. The hydraulic cylinder is an important part of the hydraulic damping system and the flow conditions inside the cylinder significantly affect its performance. However, only a few researches related to the flow field inside the hydraulic cylinder have been reported. In this study, a novel viscous damping system with opposing symmetrical hydraulic cylinders that can guarantee the smoothness of vibration absorption in a single degree of freedom is proposed. The advantage of this design is that the damping characteristic can be regulated using the external flow valve provided in the external hydraulic loop. The hydraulic damping system is simulated using the commercial software ANSYS Fluent software environment, different strokes and frequencies are applied to observe the internal flow characteristics. As can be seen from the results of numerical investigation, when the piston on one side moves, the piston on the other side also moves, and the pressure change in the cylinder is caused by the collective effect of the cavity volume change and the flow change of the hydraulic oil. In addition, by comparing the streamline and velocity distribution in the cavity under different strokes and frequencies, the relationship between vortex and velocity and compression distance is summarized. These results provide valuable information to facilitate the design of viscous damping system with symmetrical hydraulic cylinders

Mechanisms of Electroacupuncture Pretreatment in Alleviating Myocardial Ischemia Reperfusion Injury: Interactions between the Cerebellar Fastigial Nucleus and Lateral Hypothalamic Area

Yu Qing,Wu Li-bin,Zhang Fan,Wei Xiao-tong,Chen Pian-pian,Wang Shuai-ya,Cai Mei-yi,Shu Qi,Li Liao-yuan,Wu Zi-jian,Cai Rong-lin,Hu Ling 사단법인약침학회 2021 Journal of Acupuncture & Meridian Studies Vol.14 No.6

Background: Myocardial ischemia reperfusion injury (MIRI) is an important mechanism of post-myocardial infarction injury and a main cause of death in patients with ischemic heart disease. Electroacupuncture (EA) pretreatment is effective for the prevention and treatment of MIRI, but mechanisms mediating the effects of cardiovascular disease EA treatments remain unclear. Objectives: To determine whether the lateral hypothalamus (LHA) and the cerebellar fastigial nucleus (FN) are involved in the protective effects of EA stimulation on MIRI. Methods: EA pretreatment was performed for 7 days before the establishment of the MIRI model. ST-segment changes on electrocardiograms were recorded and the Curtis–Walker arrhythmia score was used to evaluate changes in reperfusion injury. Hematoxylin–eosin staining was applied to evaluate the pathological and morphological changes in myocardial tissue. c-fos expression in the LHA and FN was determined by immunofluorescence staining. Glutamic (Glu) and γ-Aminobutyric acid (GABA) levels were measured using a high-performance liquid chromatography-electrochemical method. Results: EA pretreatment reduced ST-segment elevation, arrhythmia scores, and morphological changes in MIRI myocardial cells in rats, and decreased the c-fos protein expression in LHA/FN nuclei. MIRI was associated with an imbalance between GABA and Glu levels, whereas EA pretreatment increased GABA levels and decreased Glu levels in the LHA/FN. Conclusion: FN and LHA are involved in the EA-mediated attenuation of MIRI. Pretreatment with EA plays a protective role in the myocardium by regulating Glu and GABA release in the LHA and FN.

Clinical Application of Endoscopic Inguinal Lymph Node Resection after Lipolysis and Liposuction for Vulvar Cancer

Wu, Qiang,Zhao, Yi-Bing,Sun, Zhi-Hua,Ni, Jing,Wu, Yu-Zhong,Shao, Heng-Hua,Qu, Jun-Wei,Huang, Xin-En Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Aim: To examine lymph nodes obtained after lipolysis and liposuction of subcutaneous fat of the inguinal region of female vulvar cancer patients to explore the feasibility of clinical application. Methods: The field of operation was on the basis of the range of the conventional resection of inguinal lymph nodes. We injected lipolysis liquid fanwise, started liposuction after 15-20 minutes; then the subcutaneous fatty tissue was sucked out clearly by suction tube. We selected the first puncture holes located on 2-3 cm part below anterior superior spine, the others respectively being located 3cm and 6cm below the first for puncturing into the skin, imbedding a trocar to intorduce $CO_2$ gas and the specular body, and excise the lymph nodes by ultrasonic scalpel. The surgical field chamber was set with negative pressure drainage and was pressured with a soft saline bag after surgery. Results: A lacuna emerged from subcutaneous of the inguinal region after lipolysis and liposuction, with a wide fascia easily exposed at the bottom where lymph nodes could be readily excised. The number of lymph nodes of ten patients excised within the inguinal region on each side was 4-18. The excised average number of lymph nodes was 11 when we had mature technology. Conclusion: Most of adipose tissue was removed after lipolysis and liposuction of subcutaneous tissue of inguinal region, so that the included lymph nodes were exposed and easy to excise by endoscope. This surgery avoided the large incision of regular surgery of inguinal region, the results indicating that this approach is feasible and safe for used as an alternative technology.

Numerical investigation of the mechanical component design of a hexacopter drone for real-time fine dust monitoring

Yu-Ting Wu,Zhen Qin,Amre Eizad,Sung-Ki Lyu 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.7

Multi-rotor unmanned aerial vehicles (UAVs) are being widely used in various military and civilian fields because they can replace manned systems in the performance of a variety of difficult and/or hazardous tasks. Various UAV designs have been developed to fulfill the requirements of various applications. The current work investigates the design of a hexacopter drone with foldable arms to support the six propulsion units that is designed for realtime fine dust monitoring. The propeller and foldable arm are the key mechanical power transmission components in this design, so their propulsion performance and safety reliability have been numerically investigated in this research. The finite volume method (FVM) based aerodynamic characteristics simulation is utilized to calculate and observe the operational performance of eight different proposed propeller blade designs. The optimal design was obtained through a series of comparisons of the simulation outcomes. The flow field force acting on the propeller blade was analyzed using the fluid-structure interaction (FSI) based simulation method. In addition, the design philosophy of using carbon fiber composite material to replace the traditional aluminum alloy in the manufacture of the foldable arm is presented. The rationality of this design philosophy is verified through finite element method (FEM) based structural analysis. The design experience gained from this study provides a theoretical basis for the development of components for multi-rotor UAVs.

Providing Efficient Secured Mobile IPv6 by SAG and Robust Header Compression

Wu, Tin-Yu,Chao, Han-Chieh,Lo, Chi-Hsiang Korea Information Processing Society 2009 Journal of information processing systems Vol.5 No.3

By providing ubiquitous Internet connectivity, wireless networks offer more convenient ways for users to surf the Internet. However, wireless networks encounter more technological challenges than wired networks, such as bandwidth, security problems, and handoff latency. Thus, this paper proposes new technologies to solve these problems. First, a Security Access Gateway (SAG) is proposed to solve the security issue. Originally, mobile terminals were unable to process high security calculations because of their low calculating power. SAG not only offers high calculating power to encrypt the encryption demand of SAG's domain, but also helps mobile terminals to establish a multiple safety tunnel to maintain a secure domain. Second, Robust Header Compression (RoHC) technology is adopted to increase the utilization of bandwidth. Instead of Access Point (AP), Access Gateway (AG) is used to deal with the packet header compression and de-compression from the wireless end. AG's high calculating power is able to reduce the load on AP. In the original architecture, AP has to deal with a large number of demands by header compression/de-compression from mobile terminals. Eventually, wireless networks must offer users "Mobility" and "Roaming". For wireless networks to achieve "Mobility" and "Roaming," we can use Mobile IPv6 (MIPv6) technology. Nevertheless, such technology might cause latency. Furthermore, how the security tunnel and header compression established before the handoff can be used by mobile terminals handoff will be another great challenge. Thus, this paper proposes to solve the problem by using Early Binding Updates (EBU) and Security Access Gateway (SAG) to offer a complete mechanism with low latency, low handoff mechanism calculation, and high security.

CBX7 Rejuvenates Late Passage Dental Pulp Stem Cells by Maintaining Stemness and Pro-angiogenic Ability

Wu Yu,Li Bing,Yu Dandan,Zhou Zhixuan,Shen Ming,Jiang Fei 한국조직공학과 재생의학회 2023 조직공학과 재생의학 Vol.20 No.3

BACKGROUND: Ever-growing tissue regeneration causes pressing need for large population of stem cells. However, extensive cell expansion eventually leads to impaired regenerative potentials. In this study, chromobox protein homolog 7 (CBX7) was overexpressed to rejuvenate late passage dental pulp stem cells (DPSCs-P9). METHODS: The recruitment of copper ions (Cu2?)-activated hypoxia-inducible factor-1a (HIF-1a) to the CBX7 gene promoter was confirmed by chromatin immunoprecipitation assay. Functions subsequent to Cu2?-induced or recombinant overexpression of CBX7 on proliferation, multipotency, odontoblastic differentiation and angiogenesis were investigated in vitro, while murine subcutaneous transplantation model was used to further detect the effects of Cu2?-induced CBX7 overexpression in vivo. RESULTS: Our data displayed that CBX7 overexpression maintain proliferation and multipotency of DPSCs-P9 almost as strong as those of DPSCs-P3. Both gene level of odontoblast-lineage markers and calcium precipitation were nearly the same between CBX7 overexpressed DPSCs-P9 and normal DPSCs-P3. Moreover, we also found upregulated expression of vascular endothelial growth factor in DPSCs-P9 with CBX7 overexpression, which increased the number of capillary-like structures and migrating co-cultured human umbilical vein endothelial cells as well. These findings indicate CBX7 as an effective factor to rejuvenate late passage stem cells insusceptible to cell expansion. Cu2? has been proved to achieve CBX7 overexpression in DPSCs through the initiation of HIF-1a-CBX7 cascade. Under Cu2? stimulation since P3, DPSCs-P9 exhibited ameliorated regenerative potential both in vitro and in vivo. CONCLUSION: Long-term stimulation of Cu2? to overexpress CBX7 could be a new strategy to manufacture large population of self-renewing stem cells.