Risk Factors for Surgical Site Infections after Liver Resec-tion (A Multivariate Analysis of 6,132 Patients)

( Li-yang Sun ),( Jiong-jie Yu ),( Ju-dong Li ),( Xin-fei Xu ),( Jia-he Wang ),( Bing Quan ),( Wen-tao Yan ),( Feng Shen ),( Chao Li ),( Lei Liang ),( Tian Yang ) 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

Aims: Surgical site infection (SSI) is a common postoperative complication and associated with an increased morbidity, hospital stay, and overall cost. The aim of the present study was to identify risk factors for SSIs after hepatic resection based on a large single-center cohort. Methods: A retrospective study was conducted of 6,132 patients who underwent liver resection without concomitant biliary reconstruction or gastrointestinal procedures between 2014 and 2016 at the largest hepatic center in China. The occurrences of SSI, classified as incisional SSI and organ/space SSI within 30 days after operation were investigated. Patient- and surgical-related risk variables were collected using standardized data collection form. A likelihood ratio forward regression model was used to assess the independent association of risk factors with SSI. Results: SSI developed in 587 patients (9.6%), including superficial/deep incisional SSI in 357 patients (5.8 %), and organ/ space SSI in 304 patients (5.0 %). Multivariate logistic regression analysis showed that obesity, diabetes mellitus, ASA score ≥ 2, liver cirrhosis, re-hepatectomy, hepatoliathiasis, and intraoperative blood transfusion were independent risk factors of overall SSI. However, incisional and organ/space SSI differed from each other with respect to risk factors. Among a variety of risk factors, hepatolithiasis, liver cirrhosis, and intraoperative blood transfusion were consistently associated with both incisional and organ/space SSI. Conclusions: SSI is a common complication after liver resection, and more caution should be taken in patients with hepatolithiasis or liver cirrhosis. Prevention strategies focusing on factors associated with SSI is necessary in order to reduce SSI after liver resection.

A Combination Strategy for Construction of Peptide-β2m-H-2K^b Single Chain with Overlap Extension PCR and One-Step Cloning

( Tao Xu ),( Xiaoe Li ),( You Wu ),( Khawar Ali Shahzad ),( Wei Wang ),( Lei Zhang ),( Chuanlai Shen ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.12

The time-consuming and high-cost preparation of soluble peptide-major histocompatibility complexes (pMHC) currently limits their wide uses in monitoring antigen-specific T cells. The single-chain trimer (SCT) of peptide-β2m-MHC class I heavy chain was developed as an alternative strategy, but its gene fusion is hindered in many cases owing to the incompatibility between the multiple restriction enzymes and the restriction endonuclease sites of plasmid vectors. In this study, overlap extension PCR and one-step cloning were adopted to overcome this restriction. The SCT gene of the OVA _257-264 peptide-(GS₄)₃-β2m-(GS₄)₄-H-2K^b heavy chain was constructed and inserted into plasmid pET28a by overlap extension PCR and one-step cloning, without the requirement of restriction enzymes. The SCT protein was expressed in Escherichia coli, and then purified and refolded. The resulting H-2K^b/OVA _257-264complex showed the correct structural conformation and capability to bind with OVA _257-264-specific Tcell receptor. The overlap extension PCR and one-step cloning ensure the construction of single-chain MHC class I molecules associated with random epitopes, and will facilitate the preparation of soluble pMHC multimers.

Antiproliferative activities of Garcinia bracteata extract and its active ingredient, isobractatin, against human tumor cell lines

Shen, Tao,Li, Wei,Wang, Yan-Yan,Zhong, Qing-Qing,Wang, Shu-Qi,Wang, Xiao-Ning,Ren, Dong-Mei,Lou, Hong-Xiang 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.3

In our cell based screening of antitumor ingredients from plants, the EtOH extract of Garcinia bracteata displayed antiproliferative effect against human lung adenocarcinoma A549 cells, human breast cancer MCF-7 cells, and human prostate cancer PC3 cells. Phytochemical investigation of this active extract produced nine ingredients, and their structures were established by analysis of MS and NMR spectra. Antiproliferative evaluation of isolated ingredients on A549, MCF-7 and PC3 cells indicated that a xanthone named isobractatin (1) exhibited potent antiproliferative activity against the above three human cancer cell lines with $IC_{50}$ values ranging from 2.90 to $4.15{\mu}M$. Treatment of PC3 cells with 1 led to an enhancement of the cell apoptosis, and arrested cell cycle in the G0/G1 phase. The G0/G1 phase cycle-related proteins analysis showed that the expressions of cyclins D1 and E were reduced by 1, whereas the protein level of cyclin dependent kinase (CDK) inhibitor P21 was induced. Additionally, 1 enhanced PC3 cell apoptosis by activations of Bax, caspases 3 and 9, and by inhibition of Bcl-2. Our combined data illustrated that isobractatin (1) was the antiproliferative ingredient of G. bracteata against three human cancer cell lines, which exerted its antiproliferatrive effect via cell cycle arrest and induction of apoptosis.

Antiproliferative activities of Garcinia bracteata extract and its active ingredient, isobractatin, against human tumor cell lines

Tao Shen,Wei Li,Yan-Yan Wang,Qing-Qing Zhong,Shu-Qi Wang,Xiao-Ning Wang,Dong-Mei Ren,Hongxiang Lou 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.3

In our cell based screening of antitumoringredients from plants, the EtOH extract of Garciniabracteata displayed antiproliferative effect against humanlung adenocarcinoma A549 cells, human breast cancerMCF-7 cells, and human prostate cancer PC3 cells. Phytochemicalinvestigation of this active extract producednine ingredients, and their structures were established byanalysis of MS and NMR spectra. Antiproliferative evaluationof isolated ingredients on A549, MCF-7 and PC3cells indicated that a xanthone named isobractatin (1)exhibited potent antiproliferative activity against the abovethree human cancer cell lines with IC50 values rangingfrom 2.90 to 4.15 lM. Treatment of PC3 cells with 1 led toan enhancement of the cell apoptosis, and arrested cellcycle in the G0/G1 phase. The G0/G1 phase cycle-relatedproteins analysis showed that the expressions of cyclins D1and E were reduced by 1, whereas the protein level of cyclin dependent kinase (CDK) inhibitor P21 was induced. Additionally, 1 enhanced PC3 cell apoptosis by activationsof Bax, caspases 3 and 9, and by inhibition of Bcl-2. Ourcombined data illustrated that isobractatin (1) was theantiproliferative ingredient of G. bracteata against threehuman cancer cell lines, which exerted its antiproliferatriveeffect via cell cycle arrest and induction of apoptosis.

Heterologous Expression of Rhizopus Oryzae CYP509C12 Gene in Rhizopus Nigricans Enhances Reactive Oxygen Species Production and 11α-Hydroxylation Rate of 16α, 17-Epoxyprogesterone

Shen, Chaohui,Gao, Xiyang,Li, Tao,Zhang, Jun,Gao, Yuqian,Qiu, Liyou,Zhang, Guang The Korean Society of Mycology 2019 Mycobiology Vol.47 No.3

The $11{\alpha}$-hydroxylation of $16{\alpha}$, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The $11{\alpha}$-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the $11{\alpha}$-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The $H_2O_2$ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the $11{\alpha}$-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

Fractional order viscoelasticity in characterization for atrial tissue

Shen, Jing Jin,Li, Cheng Gang,Wu, Hong Tao,Kalantari, Masoud 한국유변학회 2013 Korea-Australia rheology journal Vol.25 No.2

Atrial tissue due to its solid-like and fluid-like constituents shows highly viscoelastic properties. Up to now, the distribution pattern of muscle fiber in heart is not well established, and it is hard to establish the constitutive model for atrial tissue completely based on the microstructure level. Consider the equivalence between the fractional viscoelasticity and the fractal spring-dashpot model, a generalized fractional order Maxwell model is proposed to model the porcine atrial tissue in the phenomenological sense. This model has a simple expression and intuitively physical meanings. The constitutive parameters in the model are estimated in the complex domain by a genetic algorithm. Final results illustrate the proposed model gets a well agreement with the experimental data.

Vehicle Detection in Aerial Images Based on Hyper Feature Map in Deep Convolutional Network

( Jiaquan Shen ),( Ningzhong Liu ),( Han Sun ),( Xiaoli Tao ),( Qiangyi Li ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.4

Vehicle detection based on aerial images is an interesting and challenging research topic. Most of the traditional vehicle detection methods are based on the sliding window search algorithm, but these methods are not sufficient for the extraction of object features, and accompanied with heavy computational costs. Recent studies have shown that convolutional neural network algorithm has made a significant progress in computer vision, especially Faster R-CNN. However, this algorithm mainly detects objects in natural scenes, it is not suitable for detecting small object in aerial view. In this paper, an accurate and effective vehicle detection algorithm based on Faster R-CNN is proposed. Our method fuse a hyperactive feature map network with Eltwise model and Concat model, which is more conducive to the extraction of small object features. Moreover, setting suitable anchor boxes based on the size of the object is used in our model, which also effectively improves the performance of the detection. We evaluate the detection performance of our method on the Munich dataset and our collected dataset, with improvements in accuracy and effectivity compared with other methods. Our model achieves 82.2% in recall rate and 90.2% accuracy rate on Munich dataset, which has increased by 2.5 and 1.3 percentage points respectively over the state-of-the-art methods.

Low Image Distortion Constrained Power Saving for OLED Displays

Lin-Tao Duan,Bing Guo,Yan Shen,Ji-He Wang,Wen-Li Zhang 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.11

Organic Light Emitting Diode (OLED) displays have matured into current smartphones. How to prolong the lifetime of displays while preserving the display quality becomes a primary issue. In this paper, we propose a low image distortion constrained power-saving approach for OLED displays based on gamma correction and saturation scaling. We first investigate the impact of gamma correction and saturation scaling on the power of emissive displays. The results show that changing the gamma and saturation value can obtain lower display power consumption when original image color maps to another one. Thus, we integrate the gamma correction and the saturation scaling into a new low-power approach for OLED displays. However, low gamma and high saturation lead to distortion on displaying. To guarantee user experience in this paper, the CIEDE2000 color difference formula and the Mean Structural Similarity Index (MSSIM) are used to evaluate the effectiveness of our approach. The results show that our approach saves up significant display power with high image quality.

Copper-induced injectable hydrogel with nitric oxide for enhanced immunotherapy by amplifying immunogenic cell death and regulating cancer associated fibroblasts

Shuilin Shen,Zimeng Zhang,Haixiao Huang,Jing Yang,Xinyue Tao,Zhengjie Meng,Hao Ren,Xueming Li 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Background Immunogenic cell death (ICD) induced by different cancer treatments has been widely evaluated to recruit immune cells and trigger the specific antitumor immunity. However, cancer associated fibroblasts (CAFs) can hinder the invasion of immune cells and polarize the recruited monocytes to M2-type macrophages, which greatly restrict the efficacy of immunotherapy (IT). Methods In this study, an injectable hydrogel induced by copper (Cu) has been designed to contain antibody of PD-L1 and nitric oxide (NO) donor. The therapeutic efficacy of hydrogel was studied in 4T1 cells and CAFs in vitro and 4T1 tumor-bearing mice in vivo. The immune effects on cytotoxic T lymphocytes, dendritic cells (DCs) and macrophages were analyzed by flow cytometry. Enzyme-linked immunosorbent assay, immunofluorescence and transcriptome analyses were also performed to evaluate the underlying mechanism. Results Due to the absorbance of Cu with the near-infrared laser irradiation, the injectable hydrogel exhibits persistent photothermal effect to kill cancer cells. In addition, the Cu of hydrogel shows the Fenton-like reaction to produce reactive oxygen species as chemodynamic therapy, thereby enhancing cancer treatment and amplifying ICD. More interestingly, we have found that the released NO can significantly increase depletion of CAFs and reduce the proportion of M2-type macrophages in vitro. Furthermore, due to the amplify of ICD, injectable hydrogel can effectively increase the infiltration of immune cells and reverse the immunosuppressive tumor microenvironment (TME) by regulating CAFs to enhance the therapeutic efficacy of anti-PD-L1 in vivo. Conclusions The ion induced self-assembled hydrogel with NO could enhance immunotherapy via amplifying ICD and regulating CAFs. It provides a novel strategy to provoke a robust antitumor immune response for clinical cancer immunotherapy.

Screening, Purification, and Characterization of an Extracellular Prolyl Oligopeptidase from Coprinopsis clastophylla

Jen-Tao Chen,Mei-Li Chao,Chiou-Yen Wen,Wen-Shen Chu 한국미생물학회 2012 The journal of microbiology Vol.50 No.4

Culture filtrates of 22 mushrooms were screened for extracellular prolyl oligopeptidase activity. Four strains with relatively high enzyme activity were all from inky cap mushrooms. The production of Coprinopsis clastophylla prolyl oligopeptidase was associated with the growth of the fungus and the enzyme was not released by cell lysis. The enzyme was purified 285-fold to a specific activity of 52.05 U/mg. It was purified to a single band on a native polyacrylamide gel. However, the enzyme separated into three bands on a sodium dodecyl sulfate-polyacrylamide gel with mobility corresponding to molecular weights of approximately 84,60, and 26 kDa. The results of tandem mass spectrometric analysis revealed that the 60 kDa protein was likely a degradation product of the 84 kDa protein. The isoelectric point of the purified enzyme was 5.2. The purified enzyme had an optimal pH and temperature of 8.0 and 37°C, respectively. Diisopropyl fluorophosphate (DFP), p-chloromercuribenzoaic acid (PCMB), Hg2+, and Cu2+ strongly inhibited C. clastophylla prolyl oligopeptidase. This enzyme is a serine peptidase and one or more cysteine residues of the enzyme are close to the active site.