Epidemiology and resistance features of Acinetobacter baumannii isolates from the ward environment and patients in the burn ICU of a Chinese hospital

Yali Gong,Xiaodong Shen,Guangtao Huang,Cheng Zhang,Xiaoqiang Luo,Supeng Yin,Jing Wang,Fuquan Hu,Yizhi Peng,Ming Li 한국미생물학회 2016 The journal of microbiology Vol.54 No.8

Acinetobacter baumannii is an important opportunistic pathogen that causes severe nosocomial infections, especially in intensive care units (ICUs). Over the past decades, an everincreasing number of hospital outbreaks caused by A. baumannii have been reported worldwide. However, little attention has been directed toward the relationship between A. baumannii isolates from the ward environment and patients in the burn ICU. In this study, 88 A. baumannii isolates (26 from the ward environment and 62 from patients) were collected from the burn ICU of the Southwest Hospital in Chongqing, China, from July through December 2013. Antimicrobial susceptibility testing results showed that drug resistance was more severe in isolates from patients than from the ward environment, with all of the patient isolates being fully resistant to 10 out of 19 antimicrobials tested. Isolations from both the ward environment and patients possessed the β-lactamase genes blaOXA-51, blaOXA-23, blaAmpC, blaVIM, and blaPER. Using pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST), these isolates could be clustered into 4 major PFGE types and 4 main sequence types (ST368, ST369, ST195, and ST191) among which, ST368 was the dominant genotype. Epidemiologic and molecular typing data also revealed that a small-scale outbreak of A. baumannii infection was underway in the burn ICU of our hospital during the sampling period. These results suggest that dissemination of β-lactamase genes in the burn ICU might be closely associated with the high-level resistance of A. baumannii, and the ICU environment places these patients at a high risk for nosocomial infection. Cross-contamination should be an important concern in clinical activities to reduce hospital acquired infections caused by A. baumannii.

Frequency Response Analysis on Modified Plant of Extended State Observer

Yuqiong Zhang,Yali Xue,Donghai Li,Zhiqiang Gao,Haiming Niu,Huanpao Huang 제어로봇시스템학회 2017 제어로봇시스템학회 국제학술대회 논문집 Vol.2017 No.10

The active disturbance rejection control (ADRC) framework gives birth to a new concept, the modified plant (MP), describing the dynamics after the total disturbance is estimated and cancelled approximately. Ideally the modified plant is in integral form, to greatly simplify and fix the controller design, even though actual plant contains higher-order dynamics or dead time. This paper investigates that when such processes are modified into the integral, how the parameters of the extended state observer (ESO) impact on the dynamic characteristics and stability of the MP. Frequency-domain analyses show that the MP can gradually approach the integral form through parameters tuning. However, it should be cautious that an aggressive set of parameters may lead to an unstable modified plant in the presence of order mismatch.

Growth of Single-Walled Carbon Nanotubes from Well-Defined POSS Nanoclusters Structure

Yunyun Liu,Yali Hu,Qiran Cai,Xiangju Xu,Yin Chen,SHAOMING HUANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.1

High-quality single-walled carbon nanotubes (SWNTs) with narrow diameter distribution can be generated from well-defined Si8O12 nanoclusters structure which form from thermal decomposition of chemically modi¯ed polyhedral oligomeric silsesquioxane (POSS). The nanosized SixOy particles were proved to be responsible for the SWNT growth and believed to be the reason for the narrow diameter distribution of the as-grown SWNTs. This could be extended to other POSS. The SWNTs grown from the nanosized SixOy particles were found to be semiconducting enriched SWNTs (s-SWNTs). A facile patterning technology, direct photolithography, was developed for generating SWNT pattern, which is compatible to industrial-level fabrication of SWNTs pattern for device applications. The metal-free growth together with preferential growth of s-SWNTs and patterning in large scale from the structure-defined silicon oxide nanoclusters not only represent a big step toward the control growth of SWNTs and fabrication of devices for applications particularly in nanoelectronics and biomedicine but also provide a system for further studying and understanding the growth mechanism of SWNTs from nanosized materials and the relationship between the structure of SWNT and nonmetal catalysts.

Tuning ADRC for Multi-Variable System Based on Existing PID Parameters

Chunzhe Zhao,Yali Xue,Chun-E Huang 제어로봇시스템학회 2016 제어로봇시스템학회 국제학술대회 논문집 Vol.2016 No.10

Due to the long-time engineering practice, the existing PID controllers and their parameters contain the valuable information about the models of the industrial processes. Such information is absorbed to simplify the design and tuning process of the active disturbance rejection controller (ADRC) in this study. If one channel of the multivariable system is stabilized by PID, then ADRC can be built to replace the PID scheme, and the ADRC parameters can be calculated from the PID parameters. This technique can be operated channel by channel until all channels are stabilized by ADRC, which is verified by simulations. Moreover, the simulations imply that the presented ADRC design and tuning method can generate the feasible parameters efficiently for the plants with unknown models.

Whole RNA-sequencing and gene expression analysis of Trichoderma harzianum Tr-92 under chlamydospore-producing condition

Min Yuan,Yuanyuan Huang,Zhenhua Jia,Weina Ge,Lan Zhang,Qian Zhao,Shuishan Song,Yali Huang 한국유전학회 2019 Genes & Genomics Vol.41 No.6

Background Trichoderma is one of the most important biocontrol fungi, which could produce mycelia, conidiospores, and chlamydospores three types of propagules under different conditions. Chlamydospores are produced in harsh conditions in various fungi, and may be more resistant to adverse conditions. However, the knowledge associated with the mechanism of chlamydospore formation remained unclear in Trichoderma. Objectives This study is aimed to explore the essential genes and regulatory pathways associated with chlamydospore formation in Trichoderma. Methods The culture condition, survival rate, and biocontrol effects of chlamydospores and conidiospores from Trichoderma. harzianum Tr-92 were determined. Furthermore, the whole transcriptome profiles of T. harzianum Tr-92 under chlamydospore-producing and chlamydospore-nonproducing conditions were performed. Results T. harzianum Tr-92 produced chlamydospores under particular conditions, and chlamydospore-based formulation of T. harzianum Tr-92 exhibited higher biocontrol ability against Botrytis cinerea in cucumber than conidoiospore-based formulation. In the transcriptome analysis, a total of 2,029 differentially expressed genes (DEGs) were identified in T. harzianum Tr-92 under chlamydospore-producing condition, compared to that under chlamydospore-nonproducing condition. GO classification indicated that the DEGs were significantly enriched in 284 terms among biological process, cellular components and molecular function categories. A total of 19 pathways were observed with DEGs by KEGG analysis. Furthermore, fifteen DEGs were verified by quantitative real-time PCR, and the expression profiles were consistent with the transcriptome data. Conclusion The results would provide a basis on the molecular mechanisms underlying Trichoderma sporulation, which would assist the development and application of fungal biocontrol agents.

ROCK1 induces dopaminergic nerve cell apoptosis via the activation of Drp1-mediated aberrant mitochondrial fission in Parkinson’s disease

Qian Zhang,Changpeng Hu,Jingbin Huang,Wuyi Liu,Wenjing Lai,Faning Leng,Qin Tang,Yali Liu,Qing Wang,Min Zhou,Fangfang Sheng,Guobing Li,Rong Zhang 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Dopamine deficiency is mainly caused by apoptosis of dopaminergic nerve cells in the substantia nigra of themidbrain and the striatum and is an important pathologic basis of Parkinson’s disease (PD). Recent research has shownthat dynamin-related protein 1 (Drp1)-mediated aberrant mitochondrial fission plays a crucial role in dopaminergicnerve cell apoptosis. However, the upstream regulatory mechanism remains unclear. Our study showed that Drp1knockdown inhibited aberrant mitochondrial fission and apoptosis. Importantly, we found that ROCK1 was activated inan MPP+-induced PD cell model and that ROCK1 knockdown and the specific ROCK1 activation inhibitor Y-27632blocked Drp1-mediated aberrant mitochondrial fission and apoptosis of dopaminergic nerve cells by suppressing Drp1dephosphorylation/activation. Our in vivo study confirmed that Y-27632 significantly improved symptoms in a PDmouse model by inhibiting Drp1-mediated aberrant mitochondrial fission and apoptosis. Collectively, our findingssuggest an important molecular mechanism of PD pathogenesis involving ROCK1-regulated dopaminergic nerve cellapoptosis via the activation of Drp1-induced aberrant mitochondrial fission.