253 results on '"Siliang Zhang"'
Search Results
2. Cellular and Humoral Responses to Recombinant and Inactivated SARS-CoV-2 Vaccines in CKD Patients: An Observational Study
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Siliang Zhang, Jiaoxia He, Bin Tang, Qin Zhou, Yudong Hu, Yuan Yu, Jianwei Chen, Yi Liu, Chunmeng Li, Hong Ren, and Xiaohui Liao
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safety ,SARS-CoV-2 vaccine ,CKD ,humoral responses ,General Medicine ,cellular response - Abstract
Background: It remains unclear what B cell and humoral responses are mounted by chronic kidney disease (CKD) patients in response to recombinant and inactivated SARS-CoV-2 vaccines. In this study, we aimed to explore the cellular and humoral responses, and the safety of recombinant and inactivated SARS-CoV-2 vaccines in CKD patients. Methods: 79 CKD and 420 non-CKD individuals, who completed a full course of vaccination, were enrolled in the study. Adverse events (AEs) were collected via a questionnaire. Cellular and humoral responses were detected at 1, 3, and 6 months, including IgG antibody against the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein (anti-RBD-IgG), neutralizing antibodies (NAbs), the positive rate of NAbs and anti-RBD-IgG, RBD-atypical memory B cells (MBCs) (CD3 − CD19 + RBD + CD21 − CD27−), RBD-activated MBCs (CD3 − CD19 + RBD + CD21 − CD27+), RBD-resting MBCs (CD3 − CD19 + RBD + CD21 + CD27+), and RBD-intermediate MBCs (CD3 − CD19 + RBD + CD21 + CD27−). Results: We found no differences in the positivity rates of NAbs (70.89% vs. 79.49%, p = 0.212) and anti-RBD IgG (72.15% vs. 83.33%, p = 0.092) between the CKD and control groups. A total of 22 CKD individuals completed the full follow-up (1, 3, and 6 months). Significant and sustained declines were found at 3 months in anti-RBD IgG (26.64 BAU/mL vs. 9.08 BAU/mL, p < 0.001) and NAbs (161.60 IU/mL vs. 68.45 IU/mL p < 0.001), and at 6 months in anti-RBD IgG (9.08 BAU/mL vs. 5.40 BAU/mL, p = 0.064) and NAbs (68.45 IU/mL vs. 51.03 IU/mL, p = 0.001). Significant differences were identified in MBC subgroups between CKD patients and healthy controls, including RBD-specific atypical MBCs (60.5% vs. 17.9%, p < 0.001), RBD-specific activated MBCs (36.3% vs. 14.8%, p < 0.001), RBD-specific intermediate MBCs (1.24% vs. 42.6%, p < 0.001), and resting MBCs (1.34% vs. 22.4%, p < 0.001). Most AEs in CKD patients were mild (grade 1 and 2) and self-limiting. One patient with CKD presented with a recurrence of nephrotic syndrome after vaccination. Conclusions: The recombinant and inactivated SARS-CoV-2 vaccine was well-tolerated and showed a good response in the CKD cohort. Our study also revealed differences in MBC subtypes after SARS-CoV-2 vaccination between CKD patients and healthy controls.
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- 2023
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3. Research on Microgrid Load Prediction Based on GWO-LSSVM
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Ye Zhu, Siliang Zhang, Dan Su, and ShuangShuang Bao
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- 2023
4. Super-enhancer receives signals from the extracellular matrix to induce PD-L1-mediated immune evasion via integrin/BRAF/TAK1/ERK/ETV4 signaling
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Renfang Mao, Siliang Zhang, Yihui Fan, Shiyin Chen, Zhou Wang, Suhui Yue, Changyue Wu, Yuanyuan Wu, Xinxin Jin, Miaomiao Chen, Panpan Ma, Zhiwei Fan, and Donghua Gu
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MAPK/ERK pathway ,Cancer Research ,biology ,Chemistry ,Integrin ,Immune checkpoint ,Cell biology ,Super-enhancer ,Immune system ,Oncology ,Transcription (biology) ,Cancer cell ,biology.protein ,Transcription factor - Abstract
Objective: PD-L1 and PD-L2 expression levels determine immune evasion and the therapeutic efficacy of immune checkpoint blockade. The factors that drive inducible PD-L1 expression have been extensively studied, but mechanisms that result in constitutive PD-L1 expression in cancer cells are largely unknown. Methods: DNA elements were deleted in cells by CRISPR/Cas9-mediated knockout. Protein function was inhibited by chemical inhibitors. Protein levels were examined by Western blot, mRNA levels were examined by real-time RT-PCR, and surface protein expression was determined by cellular immunofluorescence and flow cytometry. Immune evasion was examined by in vitro T cell-mediated killing. Results: We determined the core regions (chr9: 5, 496, 378–5, 499, 663) of a previously identified PD-L1L2-super-enhancer (SE). Through systematic analysis, we found that the E26 transformation-specific (ETS) variant transcription factor (ETV4) bound to this core DNA region but not to DNA surrounding PD-L1L2SE. Genetic knockout of ETV4 dramatically reduced the expressions of both PD-L1 and PD-L2. ETV4 transcription was dependent on ERK activation, and BRAF/TAK1-induced ERK activation was dependent on extracellular signaling from αvβ3 integrin, which profoundly affected ETV4 transcription and PD-L1/L2 expression. Genetic silencing or pharmacological inhibition of components of the PD-L1L2-SE-associated pathway rendered cancer cells susceptible to T cell-mediated killing. Conclusions: We identified a pathway originating from the extracellular matrix that signaled via integrin/BRAF/TAK1/ERK/ETV4 to PD-L1L2-SE to induce PD-L1-mediated immune evasion. These results provided new insights into PD-L1L2-SE activation and pathways associated with immune checkpoint regulation in cancer.
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- 2021
5. Effectiveness and Safety of Ultrasound-Guided Local Paricalcitol Injection in Treating Secondary Hyperparathyroidism in ESRD: A Retrospective Study
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Shuqin Xie, Yuan Yu, Yi Liu, Siliang Zhang, Shiyi Yuan, Kui Fan, Bin Tang, Qin Zhou, Yuqing Sun, Rui Liu, Dan Cao, Yong Chen, Yelei Wang, Guangjun Liu, Huan Ma, Chenghui Tao, Li Zeng, and Ling Zhong
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local paricalcitol injection (LPI) ,intravenously paricalcitol (IP) ,secondary hyperparathyroidism (SHPT) ,end stage renal disease (ESRD) ,General Medicine - Abstract
Purpose: To compare the safety and efficacy of percutaneous paricalcitol injection with intravenously administered paricalcitol in treating parathyroid hyperplasia in patients with secondary hyperparathyroidism (SHPT). Methods: This study was approved by the Ethics Committee of our institution. We retrospectively collected data on patients who received percutaneous paricalcitol injection (24 patients) and intravenously administered paricalcitol (22 patients) based on their intact parathyroid hormone (iPTH) level. Serum iPTH, calcium, phosphorus, and the volume of the parathyroid gland were measured at several indicated time points after treatment, and adverse events associated with the two treatments were evaluated. Results: After 6 months of follow-up, we found that patients from the percutaneous injection group had significantly decreased levels of iPTH (from 1887.81 ± 726.81 pg/mL to 631.06 ± 393.06 pg/mL), phosphate (from 1.94 ± 0.36 mmol/L to 1.71 ± 0.34 mmol/L), and volume of the parathyroid gland (from 0.87 ± 0.50 cm3 to 0.60 ± 0.36 cm3), with relief from ostealgia within 48–72 h. In the intravenously administered group, the levels of iPTH decreased from 686.87 ± 260.44 pg/mL to 388.47 ± 167.36 pg/mL; while there was no significant change in phosphate levels, the volume of the parathyroid gland and ostealgia relief were observed at the end of follow-up. The serum calcium level did not significantly change, and no severe complications were observed in both groups. In vitro fluorescence-activated single cell sorting (FACS) analysis indicated that paricalcitol induced parathyroid cell apoptosis in a dose-dependent manner. Conclusions: Percutaneous paricalcitol injection is a selective treatment for SHPT in ESRD.
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- 2022
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6. Lead and copper influenced bile acid metabolism by changing intestinal microbiota and activating farnesoid X receptor in Bufo gargarizans
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Yutian Liu, Siliang Zhang, Hongzhang Deng, Aixia Chen, and Lihong Chai
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Environmental Engineering ,Environmental Chemistry ,Pollution ,Waste Management and Disposal - Abstract
Lead (Pb) and copper (Cu) are ubiquitous metal contaminants and can pose a threat to ecosystem and human health. Bile acids have recently received considerable attention for their role in the maintenance of health. However, there were few studies on whether Pb and Cu affect bile acid metabolism in amphibians. In this study, a combination approach of histological analysis, targeted metabolomics, 16S rDNA sequencing and qPCR was used to explore the impacts of Pb, Cu and their mixture (Mix) on bile acid in Bufo gargarizans tadpoles. The results showed that Pb, Cu, and Mix resulted in intestinal damage and altered the bile acid profiles. Specifically, Pb and Mix exposure decreased total bile acid concentrations while increased toxic bile acid levels; in contrast, Cu exposure increased total bile acid levels. And hydrophilic bile acids were reduced in all treated tadpoles. Moreover, Pb and/or Cu changed the composition of intestinal microbiota, especially Clostridia, Bacteroides and Eubacterium involved in bile acid biotransformation. qPCR revealed that the decreased total bile acid concentrations in Pb- and Mix-treated tadpoles were most likely attributed to the activation of intestinal farnesoid X receptor (Fxr), which suppressed bile acid synthesis and reabsorption. While activated fxr in the Cu treatment group may be a regulatory mechanism in response to increased bile excretion, which is a detoxification route of tadpoles under Cu stress. Collectively, Pb, Cu and Mix changed bile acid profiles by affecting intestinal microbial composition and activating Fxr signaling. This study provided insight into the impacts of Pb and Cu on bile acid metabolism and contributed to the assessment of the potential ecotoxicity of heavy metals on amphibians.
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- 2022
7. Land Use/Cover Change and Its Relationship with Regional Development in Xixian New Area, China
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Siliang Zhang, Zilong Guan, Yan Liu, and Feimin Zheng
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Renewable Energy, Sustainability and the Environment ,land-use change ,land use degree ,land use benefits ,regional development ,Xixian New Area ,Geography, Planning and Development ,Management, Monitoring, Policy and Law - Abstract
There is a close relationship between land use/cover change and regional development in new urban areas. In this paper, based on the land-use data before (2010, 2013) and after (2015, 2018) the establishment of Xixian New Area and the economic development data of the corresponding period, with the help of indexes such as the land use transfer matrix, relative change rate/net change rate and the composite index of land use degree, the temporal and spatial differences of land-use change and land use degree in the ten years before and after the establishment of Xixian New Area were analyzed, and the driving factors of land-use change and their relationship with the level of social and economic development were discussed. The results indicate that cultivated land and construction land are the main land-use types in Xixian New Area in the whole studying period. From 2010 to 2018, the area of cultivated land and forest land in the region decreased over time, but the construction land area continuously increased dramatically (increased by 36.5% from 2010 to 2018) and the land-use change corresponds basically to the construction and development process of the New Area. In the spatial transfer of land use, the transformation of cultivated land to construction land was the most evident, and the urbanization construction in the New Area occupied the most cultivated land. The composite index of land use degree in the New Area was generally high and increased with time. Geographical location and policy guidance are the main reasons for the spatial difference of land use degree. The land use benefits in the New Area increased significantly, and the land use degree was positively correlated with the level of regional, social and economic development. The main driving factor of land-use change was human activities guided by policy.
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- 2022
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8. Intestinal response of Rana chensinensis larvae exposed to Cr and Pb, alone and in combination
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Siliang Zhang, Aixia Chen, Hongzhang Deng, Ling Jiang, Xiaoli Liu, and Lihong Chai
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Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,General Medicine ,Pollution - Published
- 2023
9. GPHB5 Is a Biomarker in Women With Metabolic Syndrome: Results From Cross-Sectional and Intervention Studies
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Ting Xiang, Siliang Zhang, Qinge Li, Ling Li, Hua Liu, Chen Chen, Gangyi Yang, and Mengliu Yang
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Metabolic Syndrome ,Cross-Sectional Studies ,Endocrinology, Diabetes and Metabolism ,Humans ,Female ,Adiponectin ,Insulin Resistance ,Lipid Metabolism ,Biomarkers ,Glycoproteins - Abstract
BackgroundAnimal studies have found that GPHB5 has a similar effect on system metabolism as TSH. However, the relationship between GPHB5 and metabolic diseases remains unknown. This study investigates the relationship between GPHB5 and MetS in young women.MethodsBioinformatics analysis was undertaken to explore the relationship between GPHB5 and metabolic-related genes and signaling pathways. EHC and OGTT were performed on all individuals. Lipid-infusion, physical activity, and cold-exposure tests were performed on healthy individuals. Serum GPHB5 concentrations were measured by an ELISA kit.ResultsPPI network showed that 11 genes interacted with GPHB5, in which POMC and KISS1R were involved in glucose and lipid metabolism. GO analysis showed 56 pathways for BP and 16 pathways for MF, in which OPRM1 and MCR families were related to energy metabolism. KEGG analysis found that GPHB5 is associated with lipolysis and neuroactive ligand-receptor interaction pathways. The levels of circulating GPHB5 were significantly increased, while serum adiponectin levels were lower in MetS women compared with healthy women. Obese/overweight individuals had lower adiponectin levels and higher GPHB5 levels. Circulating GPHB5 levels were positively correlated with BMI, WHR, blood pressure, FBG, 2 h-BG, HbA1c, FIns, 2h-Ins, LDL-C, FFA, HOMA-IR, and AUCg, etc. but negatively correlated with HDL-C, adiponectin, and M-values. Serum GPHB5 levels did not change significantly during the OGTT, EHC, and lipid infusion. Physical activity and cold-exposure tests did not lead to changes in GPHB5 levels. GLP-1RA treatment resulted in a significant decrease in serum GPHB5 levels.ConclusionsGPHB5 may be a biomarker for MetS.
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- 2022
10. Oxygen Uptake Rate Controlling Strategy Balanced with Oxygen Supply for Improving Coenzyme Q10 Production by Rhodobacter sphaeroides
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Siliang Zhang, Yingping Zhuang, Zejian Wang, Meijin Guo, Zhang Xingzi, Zhiwei Sui, and Ping Wang
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0106 biological sciences ,Coenzyme Q10 ,0303 health sciences ,Ammonium sulfate ,biology ,Chemistry ,Biomedical Engineering ,Q10 ,Bioengineering ,Metabolism ,biology.organism_classification ,01 natural sciences ,Applied Microbiology and Biotechnology ,03 medical and health sciences ,Rhodobacter sphaeroides ,chemistry.chemical_compound ,010608 biotechnology ,Yield (chemistry) ,Fermentation ,Food science ,Industrial and production engineering ,030304 developmental biology ,Biotechnology - Abstract
The effects of different oxygen uptake rates (OUR) on the physiological metabolism of Rhodobacter sphaeroides were investigated systematically in 50 L fermenters due to the significant influence on industrial coenzyme Q10 production under oxygen supply limitation. Meanwhile, the seriously decreased oxygen transfer rate caused by the increased broth viscosity was successfully prevented with OUR-directed continuous ammonium sulfate feeding in the late fermentation phase. The statistical analysis results showed that controlling OUR constantly at 45 ± 2.2 mmol/L/h by the oxygen supply level adjustment and the continuous ammonium sulfate feeding could greatly enhance Q10 production. This OUR-Stat controlling strategy successfully achieved the maximal coenzyme Q10 production (2584 ± 82 mg/L), which was 15.4% higher than that of the control. The highest specific CoQ10 content was 25.9 mg/(g DCW)), and the yield of CoQ10 to glucose consumption was up to 19.37 mg/g. These results demonstrated that the optimal OUR-Stat controlling strategy would be effective and economical for improving the industrial CoQ10 production.
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- 2020
11. Quantitation of meropenem in dried blood spots using microfluidic-based volumetric sampling coupled with LC-MS/MS bioanalysis in preterm neonates
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Linlin Hu, Jinlu Zhang, Jie He, Siliang Zhang, Dongxue Liu, and Hua Shao
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Clinical Biochemistry ,Cell Biology ,General Medicine ,Biochemistry ,Analytical Chemistry - Published
- 2023
12. Application of human-computer interaction technology in rehabilitation treatment of mental and nervous system diseases
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Haolin Cai, Xiaozhen Ding, and Siliang Zhang
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General Medicine - Abstract
With the development of human-computer interaction technology, how to use intelligent, natural and efficient interaction to promote the development of medicine has gradually become a hot topic of research. Mental and nervous system diseases have a great impact on the quality of people’s daily life. The use of human-computer interaction technology to rehabilitate mental and nervous system diseases can improve the treatment effect and reduce the work intensity of doctors, so it has far-reaching clinical significance. This paper first describes the development process of human-computer interaction technology, and then focuses on the application of human-computer interaction technology such as interactive pen, voice interaction, gait/gesture interaction and physiological computing in the rehabilitation treatment of mental and nervous system diseases, which has important practical significance for improving the use of computer technology to improve traditional medical treatment methods.
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- 2023
13. Lead and copper led to the dysregulation of bile acid homeostasis by impairing intestinal absorption in Bufo gargarizans larvae: An integrated metabolomics and transcriptomics approach
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Yutian, Liu, Siliang, Zhang, Hongzhang, Deng, Aixia, Chen, and Lihong, Chai
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Environmental Engineering ,Pollution ,Bufonidae ,Bile Acids and Salts ,Lead ,Intestinal Absorption ,Larva ,Metals, Heavy ,Animals ,Homeostasis ,Metabolomics ,Environmental Chemistry ,Transcriptome ,Waste Management and Disposal ,Copper - Abstract
Bile acids, as metabolic regulators and signaling molecules, play key roles in the regulation of host metabolism and immune responses. Heavy metals such as lead (Pb) and copper (Cu) are widespread environmental pollutants that threaten public health. However, the effects of heavy metals on bile acid metabolism and the underlying molecular mechanisms remain unclear, particularly for ecologically important amphibian species. In the present research, the effects of exposure to environmentally-relevant concentrations of Pb (250 μg/L), Cu (50 μg/L), and a mixture of both (Mix) on bile acid metabolism and the underlying molecular mechanisms in the intestines of Bufo gargarizans larvae were comprehensively investigated using histopathology, metabolomics and transcriptomics analysis. Our results suggested that Pb and/or Cu caused histopathological damage to the intestine and liver, such as decreased intestinal epithelial cell height and dilated hepatic sinusoid. The total bile acid level was decreased in the Pb and Mix exposure groups but elevated in the Cu treatment. A significant decrease in the ratio of conjugated to unconjugated bile acids was present in all treatment groups. Also, the level of GCA was increased while TCA and TCDCA were decreased in all exposure groups. In addition, exposure to Pb and Cu altered the expression levels of genes related to intestinal absorption. For example, mrp2, mrp3 and aqp4 had higher expression in the Pb and Mix treatment groups, and aqp1 and mrp4 were increased in the Cu treatment group. Overall, we speculated that the dysregulation of bile acid homeostasis induced by Pb and Cu exposure may be due to impaired intestinal absorption. These findings raise further concerns about the hazards of Pb and/or Cu in influencing bile acid metabolism that might lead to the development of metabolic diseases and inflammatory disorders.
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- 2023
14. Coupled metabolic‐hydrodynamic modeling enabling rational scale‐up of industrial bioprocesses
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Ju Chu, Henk Noorman, Wenjun Tang, Guan Wang, Yingping Zhuang, Cees Haringa, and Siliang Zhang
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Computer science ,Bioengineering ,Models, Biological ,Applied Microbiology and Biotechnology ,Metabolic engineering ,Synthetic biology ,Bioreactors ,Metabolomics ,Metabolic Engineering ,Industrial design ,SCALE-UP ,Hydrodynamics ,Computer Simulation ,Biochemical engineering ,Bioprocess ,Flux (metabolism) ,Fluxomics ,Biotechnology - Abstract
Metabolomics aims to address what and how regulatory mechanisms are coordinated to achieve flux optimality, different metabolic objectives as well as appropriate adaptations to dynamic nutrient availability. Recent decades have witnessed that the integration of metabolomics and fluxomics within the goal of synthetic biology has arrived at generating the desired bioproducts with improved bioconversion efficiency. Absolute metabolite quantification by isotope dilution mass spectrometry represents a functional readout of cellular biochemistry and contributes to the establishment of metabolic (structured) models required in systems metabolic engineering. In industrial practices, population heterogeneity arising from fluctuating nutrient availability frequently leads to performance losses, that is reduced commercial metrics (titer, rate, and yield). Hence, the development of more stable producers and more predictable bioprocesses can benefit from a quantitative understanding of spatial and temporal cell-to-cell heterogeneity within industrial bioprocesses. Quantitative metabolomics analysis and metabolic modeling applied in computational fluid dynamics (CFD)-assisted scale-down simulators that mimic industrial heterogeneity such as fluctuations in nutrients, dissolved gases, and other stresses can procure informative clues for coping with issues during bioprocessing scale-up. In previous studies, only limited insights into the hydrodynamic conditions inside the industrial-scale bioreactor have been obtained, which makes case-by-case scale-up far from straightforward. Tracking the flow paths of cells circulating in large-scale bioreactors is a highly valuable tool for evaluating cellular performance in production tanks. The "lifelines" or "trajectories" of cells in industrial-scale bioreactors can be captured using Euler-Lagrange CFD simulation. This novel methodology can be further coupled with metabolic (structured) models to provide not only a statistical analysis of cell lifelines triggered by the environmental fluctuations but also a global assessment of the metabolic response to heterogeneity inside an industrial bioreactor. For the future, the industrial design should be dependent on the computational framework, and this integration work will allow bioprocess scale-up to the industrial scale with an end in mind.
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- 2019
15. Harnessing the intracellular triacylglycerols for titer improvement of polyketides in Streptomyces
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Yi Yang, Wensheng Xiang, Xiangyin Chen, Gao-Yi Tan, Guomin Ai, Gil Alterovitz, Yihong Li, Zilong Li, Lixin Zhang, Siliang Zhang, Weishan Wang, Chen Yang, Guanghou Shui, Keqiang Fan, Xueting Liu, Zhiheng Yang, Pinjiao Jin, H. Kathleen Dannelly, Sin Man Lam, Jie Zhang, Shanshan Li, Xuekui Xia, and Hongzhong Lu
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Streptomyces venezuelae ,0303 health sciences ,biology ,Streptomyces coelicolor ,Biomedical Engineering ,Streptomyces rimosus ,Bioengineering ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Streptomyces ,Actinorhodin ,03 medical and health sciences ,Polyketide ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,Biochemistry ,Molecular Medicine ,Streptomyces avermitilis ,030217 neurology & neurosurgery ,Avermectin ,030304 developmental biology ,Biotechnology - Abstract
Pharmaceutically important polyketides such as avermectin are mainly produced as secondary metabolites during the stationary phase of growth of Streptomyces species in fermenters. The source of intracellular metabolites that are funneled into polyketide biosynthesis has proven elusive. We applied multi-omics to reveal that intracellular triacylglycerols (TAGs), which accumulates in primary metabolism, are degraded during stationary phase. This process could channel carbon flux from both intracellular TAGs and extracellular substrates into polyketide biosynthesis. We devised a strategy named ‘dynamic degradation of TAG’ (ddTAG) to mobilize the TAG pool and increase polyketide biosynthesis. Using ddTAG we increased the titers of actinorhodin, jadomycin B, oxytetracycline and avermectin B1a in Streptomyces coelicolor, Streptomyces venezuelae, Streptomyces rimosus and Streptomyces avermitilis. Application of ddTAG increased the titer of avermectin B1a by 50% to 9.31 g l−1 in a 180-m3 industrial-scale fermentation, which is the highest titer ever reported. Our strategy could improve polyketide titers for pharmaceutical production. Polyketide yields in Streptomyces are boosted by routing stored intracellular triacylglycerol into pathways that make industrially relevant products.
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- 2019
16. Screening endogenous signal peptides and protein folding factors to promote the secretory expression of heterologous proteins in Pichia pastoris
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Duan Guangdong, Siliang Zhang, Ju Chu, Wei Dongsheng, Jiangchao Qian, Hangcheng Zhou, and Ding Lumei
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0106 biological sciences ,0301 basic medicine ,Signal peptide ,Protein Folding ,Proteome ,Saccharomyces cerevisiae ,Gene Expression ,Heterologous ,Bioengineering ,Protein Sorting Signals ,Protein Engineering ,Signal peptide processing ,01 natural sciences ,Applied Microbiology and Biotechnology ,Pichia ,Green fluorescent protein ,Pichia pastoris ,Fungal Proteins ,03 medical and health sciences ,Genes, Reporter ,010608 biotechnology ,Reporter gene ,biology ,Chemistry ,General Medicine ,biology.organism_classification ,Recombinant Proteins ,030104 developmental biology ,Biochemistry ,Protein folding ,Genome, Bacterial ,Biotechnology - Abstract
Secretory expression is most often desired but usually hampered by limitations of signal peptide processing and protein folding in the methylotrophic yeast Pichia pastoris. To alleviate such limitations, novel endogenous signal peptides (Dan4, Gas1, Msb2, and Fre2) and folding factors (Mpd1p, Pdi2p, and Sil1p) were predicted based on the reported P. pastoris secretome and genome. Their effects were investigated using three reporter proteins: yeast-enhanced green fluorescent protein (yEGFP), β-galactosidase (Gal) and cephalosporin C acylase (SECA), in comparison with the commonly used Saccharomyces cerevisiae alpha-mating factor pre-pro leader sequence (α-MF) or folding factors (Pdi1p, BiP, and Hac1p). The newly identified signal sequences were superior over α-MF for production of heterologous proteins. The signal peptide Msb2 increased the specific extracellular production of all reporter proteins, ranging from 1.5- to 8.0-fold, and Dan4 enhanced all total protein production up to 172-fold. Co-expression of folding factors exhibited a protein-specific effect on cell growth, transcription and expression of different reporter genes. All of the novel folding factors enhanced total production of SECA, and Sil1p performed best in the extracellular SECA production, showing a 3.3-fold increase. These novel signal peptides and folding factors can be used for promoting secretion of heterologous proteins in P. pastoris.
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- 2019
17. Phosphate limitation increases coenzyme Q10 production in industrial Rhodobacter sphaeroides HY01
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Haihong Chen, Xu Zheng, Lan Xu, Ke-Feng Wang, Zhichun Zhu, Chuan Li, Lixin Zhang, Siliang Zhang, Zhan Guanghuang, Lu Zhang, Gao-Yi Tan, Leshi Liu, Liming Zhou, Xiuliang Yang, Dan Li, Tong Shi, Yuanhang Li, Hui Xu, Weishan Wang, and Biqin Chen
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0106 biological sciences ,Antioxidant ,lcsh:Biotechnology ,Scale-up ,medicine.medical_treatment ,Biomedical Engineering ,Respiratory chain ,R sphaeroides ,01 natural sciences ,Applied Microbiology and Biotechnology ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Rhodobacter sphaeroides ,Biosynthesis ,Structural Biology ,lcsh:TP248.13-248.65 ,010608 biotechnology ,Genetics ,medicine ,Overproduction ,lcsh:QH301-705.5 ,030304 developmental biology ,Coenzyme Q10 ,0303 health sciences ,biology ,CoQ10 ,biology.organism_classification ,Phosphate ,lcsh:Biology (General) ,chemistry ,Biochemistry ,Fermentation ,Transcriptome ,Phosphate limitation - Abstract
Coenzyme Q10 (CoQ10) is an important component of the respiratory chain in humans and some bacteria. As a high-value-added nutraceutical antioxidant, CoQ10 has excellent capacity to prevent cardiovascular disease. The content of CoQ10 in the industrial Rhodobacter sphaeroides HY01 is hundreds of folds higher than normal physiological levels. In this study, we found that overexpression or optimization of the synthetic pathway failed CoQ10 overproduction in the HY01 strain. Moreover, under phosphate- limited conditions (decreased phosphate or in the absence of inorganic phosphate addition), CoQ10 production increased significantly by 12% to220 mg/L, biomass decreased by 12%, and the CoQ10 productivity of unit cells increased by 27%. In subsequent fed-batch fermentation, CoQ10 production reached 272 mg/L in the shake-flask fermentation and 1.95 g/L in a 100-L bioreactor under phosphate limitation. Furthermore, to understand the mechanism associated with CoQ10 overproduction under phosphate- limited conditions, the comparatve transcriptome analysis was performed. These results indicated that phosphate limitation combined with glucose fed-batch fermentation represented an effective strategy for CoQ10 production in the HY01. Phosphate limitation induced a pleiotropic effect on cell metabolism, and that improved CoQ10 biosynthesis efficiency was possibly related to the disturbance of energy metabolism and redox potential. Keywords: R sphaeroides, CoQ10, Phosphate limitation, Overproduction, Scale-up, Transcriptome
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- 2019
18. Super-enhancer receives signals from the extracellular matrix to induce PD-L1-mediated immune evasion
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Panpan, Ma, Xinxin, Jin, Zhiwei, Fan, Zhou, Wang, Suhui, Yue, Changyue, Wu, Shiyin, Chen, Yuanyuan, Wu, Miaomiao, Chen, Donghua, Gu, Siliang, Zhang, Renfang, Mao, and Yihui, Fan
- Abstract
PD-L1 and PD-L2 expression levels determine immune evasion and the therapeutic efficacy of immune checkpoint blockade. The factors that drive inducible PD-L1 expression have been extensively studied, but mechanisms that result in constitutive PD-L1 expression in cancer cells are largely unknown.DNA elements were deleted in cells by CRISPR/Cas9-mediated knockout. Protein function was inhibited by chemical inhibitors. Protein levels were examined by Western blot, mRNA levels were examined by real-time RT-PCR, and surface protein expression was determined by cellular immunofluorescence and flow cytometry. Immune evasion was examined byWe determined the core regions (chr9: 5, 496, 378-5, 499, 663) of a previously identified PD-L1L2-super-enhancer (SE). Through systematic analysis, we found that the E26 transformation-specific (ETS) variant transcription factor (ETV4) bound to this core DNA region but not to DNA surrounding PD-L1L2SE. Genetic knockout of ETV4 dramatically reduced the expressions of both PD-L1 and PD-L2. ETV4 transcription was dependent on ERK activation, and BRAF/TAK1-induced ERK activation was dependent on extracellular signaling from αvβ3 integrin, which profoundly affected ETV4 transcription and PD-L1/L2 expression. Genetic silencing or pharmacological inhibition of components of the PD-L1L2-SE-associated pathway rendered cancer cells susceptible to T cell-mediated killing.We identified a pathway originating from the extracellular matrix that signaled
- Published
- 2021
19. The association between urate-lowering therapies and treatment-related adverse events, liver damage, and major adverse cardiovascular events (MACE): A network meta-analysis of randomized trials
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Siliang Zhang, Yuan Yu, Jing Guo, Qingyue Deng, Qiming Xie, Ling Zhong, Shuqing Xie, and Jianwei Chen
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medicine.medical_specialty ,Allopurinol ,Network Meta-Analysis ,Hyperuricemia ,Placebo ,law.invention ,Gout Suppressants ,chemistry.chemical_compound ,Febuxostat ,Randomized controlled trial ,law ,Internal medicine ,medicine ,Humans ,Pharmacology (medical) ,Adverse effect ,Randomized Controlled Trials as Topic ,business.industry ,Lesinurad ,medicine.disease ,Uric Acid ,Topiroxostat ,chemistry ,Cardiovascular Diseases ,Chemical and Drug Induced Liver Injury ,business ,Mace ,medicine.drug - Abstract
Purpose Hyperuricemia is a common disease that may lead to gout, renal damage, and cardiovascular events. Oral medication is the main treatment for hyperuricemia patients when lifestyle intervention fails. An evaluation of the safety of various urate-lowering therapies (ULTs) is integral to clinical decision-making. We constructed a network meta-analysis (NMA) to evaluate the safety of oral ULTs. Methods MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched up to April 1, 2021, for randomized controlled trials that examined the safety of ULTs. The language restriction was English. The three outcomes used to assess the safety of uric acid lowering medications were treatment-related adverse events, liver damage, and major adverse cardiovascular events (MACE). Results Thirty-two trials enrolling 23,868 individuals were included in the study. In terms of treatment-related adverse events, there were no statistically significant differences between five uric acid lowering medications and placebo: allopurinol (risk ratio (RR): 1.08; 95% credible interval (CrI): 0.91, 1.29), febuxostat (RR: 1.05; 95% CrI: 0.89, 1.25), lesinurad (RR: 1.19; 95% CrI: 0.85, 1.67), lesinurad combined with xanthine oxidase inhibitor (XOI, RR: 1.05; 95% CrI: 0.83, 1.32), and topiroxostat (RR: 1.01; 95% CrI: 0.83, 1.23). Topiroxostat likely increases risk of liver damage (RR: 2.65; 95%CI: 1.24, 5.70; NNH: 33.40) as compared with placebo. With regard to MACE, there were no statistically significant differences between three uric acid lowering medications and placebo: allopurinol (RR: 0.63; 95% CrI: 0.36, 1.34), febuxostat (RR: 0.69; 95% CrI: 0.38, 1.66), and lesinurad combined with XOI (RR: 0.56; 95% CrI: 0.23, 1.85). The rankings of different interventions were depicted by cumulative ranking curve (SUCRA). Conclusions Through NMA, we provide some evidence for the safety of ULTs. We found no statistically significant differences in their effects on treatment-related adverse events and MACE. However, topiroxostat likely increases the risk of liver damage.
- Published
- 2021
20. Structured Latent Factor Analysis for Large-scale Data: Identifiability, Estimability, and Their Implications
- Author
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Xiaoou Li, Siliang Zhang, and Yunxiao Chen
- Subjects
FOS: Computer and information sciences ,Statistics and Probability ,05 social sciences ,Measure (physics) ,Behavioural sciences ,Large scale data ,01 natural sciences ,Confirmatory factor analysis ,Methodology (stat.ME) ,010104 statistics & probability ,Factor (programming language) ,0502 economics and business ,Econometrics ,Identifiability ,HA Statistics ,QA Mathematics ,0101 mathematics ,Statistics, Probability and Uncertainty ,Psychology ,computer ,Statistics - Methodology ,050205 econometrics ,Factor analysis ,computer.programming_language - Abstract
–Latent factor models are widely used to measure unobserved latent traits in social and behavioral sciences, including psychology, education, and marketing. When used in a confirmatory manner, design information is incorporated as zero constraints on corresponding parameters, yielding structured (confirmatory) latent factor models. In this article, we study how such design information affects the identifiability and the estimation of a structured latent factor model. Insights are gained through both asymptotic and nonasymptotic analyses. Our asymptotic results are established under a regime where both the number of manifest variables and the sample size diverge, motivated by applications to large-scale data. Under this regime, we define the structural identifiability of the latent factors and establish necessary and sufficient conditions that ensure structural identifiability. In addition, we propose an estimator which is shown to be consistent and rate optimal when structural identifiability holds. Finally, a nonasymptotic error bound is derived for this estimator, through which the effect of design information is further quantified. Our results shed lights on the design of large-scale measurement in education and psychology and have important implications on measurement validity and reliability.
- Published
- 2019
21. Numerical and experimental assessment of a miniature bioreactor equipped with a mechanical agitator and non‐invasive biosensors
- Author
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Jianye Xia, Huadong Peng, Jiangtao Tian, Haifeng Hang, Chao Li, Zhang Ming, Siliang Zhang, and Wang Weifei
- Subjects
Materials science ,Renewable Energy, Sustainability and the Environment ,business.industry ,General Chemical Engineering ,Organic Chemistry ,Non invasive ,Mixing (process engineering) ,Mechanics ,Computational fluid dynamics ,Pollution ,Agitator ,Inorganic Chemistry ,Shear rate ,Fuel Technology ,Mass transfer ,Bioreactor ,business ,Waste Management and Disposal ,Biosensor ,Biotechnology - Published
- 2019
22. Numerical simulation of scaling-up an inverted frusto-conical shaking bioreactor with low shear stress for mammalian cell suspension culture
- Author
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Chao Li, Ning Ding, Meijin Guo, Siliang Zhang, and Ali Mohsin
- Subjects
0301 basic medicine ,Computer simulation ,Chemistry ,Short Communication ,Chinese hamster ovary cell ,Clinical Biochemistry ,technology, industry, and agriculture ,Biomedical Engineering ,Bioengineering ,Cell Biology ,equipment and supplies ,Shear rate ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Volume (thermodynamics) ,030220 oncology & carcinogenesis ,SCALE-UP ,Shear stress ,Bioreactor ,Biophysics ,Scaling ,Biotechnology - Abstract
Shear stress is one of the key factors affecting the large-scale culture of mammalian cells. In this study, numerical simulation based on computational fluid dynamics was used to conduct a flow-field analysis of 7, 50, 200, and 1200 L inverted frusto-conical shaking bioreactors. The results show that the shear rate, specific mass transfer area (a), and volumetric oxygen mass transfer coefficient (k(L)a) gradually decreased as the scale of the bioreactor increased. Through application of BHK21 and CHO cells in 7, 200, and 1200 L bioreactors, it was found that the cell density and antibody expression level increased as the volume of the bioreactor increased. Moreover, the antibody expression level in a 1200 L bioreactor was nearly 30% and 35% higher than that of 7 and 200 L bioreactors, respectively. The results demonstrate that the environment with a larger volume is more suitable for the growth and antibody expression of CHO cells, indicating shear stress might be the most critical factor affecting the scale-up of mammalian cells. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10616-019-00308-3) contains supplementary material, which is available to authorized users.
- Published
- 2019
23. Modelling steady state intercellular isotopic distributions with isotopomer decomposition units
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Siliang Zhang, Mingzhi Huang, Weilu Lin, Yingping Zhuang, and Zejian Wang
- Subjects
Work (thermodynamics) ,Steady state ,020209 energy ,General Chemical Engineering ,Linear system ,02 engineering and technology ,Decomposition ,Computer Science Applications ,Isotopomers ,Set (abstract data type) ,Nonlinear system ,Distribution (mathematics) ,020401 chemical engineering ,0202 electrical engineering, electronic engineering, information engineering ,Applied mathematics ,0204 chemical engineering ,Mathematics - Abstract
In the past three decades, various computational frameworks for the modelling of the intracellular isotopic distribution have been proposed by different research groups. Among them the cascaded linear systems are the most popular approaches since they can transfer the nonlinear isotopomer labeling system into cascaded linear sub-systems. In this work, a novel two-step decomposition algorithm to model isotopomer labeling system is proposed. It can be utilized to decompose large metabolic networks. For convenience purpose, a new concept of isotopomer decomposition units (IDUs) is defined to distinguish the approach from others. Comparing to other cascaded linear systems, the IDU method follows a different decomposition procedure and results in another set of cascaded linear systems with different coefficients. Two variants of IDU algorithms are proposed, while one variant of them (IDU-B) has fewer number of balance equations than that of EMU balance equations. The efficiency of the IDU approach is demonstrated through two simulated examples.
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- 2019
24. Low Common Mode Noise Half-Bridge LLC DC–DC Converter With an Asymmetric Center Tapped Rectifier
- Author
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Xinke Wu and Siliang Zhang
- Subjects
Physics ,Rectifier ,Noise measurement ,business.industry ,Electromagnetic coil ,Noise reduction ,Electrical engineering ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Capacitance ,Electromagnetic interference ,Noise (radio) - Abstract
Half-bridge LLC dc–dc converter is popular in electric vehicle on-board charger due to its soft switching, high-power density, and low cost. But, it also has serious electromagnetic interference problems in that the half-bridge structure brings asymmetry common mode (CM) noise source by switching. So, this letter proposes an asymmetric center tapped rectifier (ACTR) to reduce the CM noise in half-bridge LLC without additional components. With ACTR, the CM noise source on primary winding is cancelled by CM noise sources on secondary windings. The CM noise reduction of the proposed ACTR is verified by a 1.1-kW half-bridge LLC prototype with 800 V input and 300–450 V output.
- Published
- 2019
25. Ammonium adsorption on particles with different grain sizes sieved by sediment resuspension
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Siliang Zhang, Qiuwen Chen, Kai Xie, and Qitao Yi
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Chemistry ,Environmental chemistry ,Sediment ,Ammonium adsorption - Published
- 2019
26. Variable selection in partial least squares with the weighted variable contribution to the first singular value of the covariance matrix
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Yingping Zhuang, Siliang Zhang, Haifeng Hang, and Weilu Lin
- Subjects
0301 basic medicine ,Covariance matrix ,Process Chemistry and Technology ,010401 analytical chemistry ,Feature selection ,Interval (mathematics) ,01 natural sciences ,0104 chemical sciences ,Computer Science Applications ,Analytical Chemistry ,Weighting ,03 medical and health sciences ,Singular value ,030104 developmental biology ,Partial least squares regression ,Algorithm ,Spectroscopy ,Software ,Selection (genetic algorithm) ,Mathematics ,Variable (mathematics) - Abstract
The selection of informative variables in partial least squares (PLS) is important in process analytical technology (PAT) applications in the pharmaceutical industry, for example, the calibration of spectrometers. In the past, numerous approaches have been proposed to select the variables in partial least squares. In this work, a new variable selection method for PLS with the weighted variable contribution (PLS-WVC) to the first singular value of the covariance matrix for each PLS component is proposed. Several variants of PLS-WVC with different weighting factors are proposed. One variant of PLS-WVC is equivalent to the PLS with variable importance in projection (PLS-VIP). However, the variants with the correlation between X γ w γ and Y γ q γ as the weighting factor are preferred based on the results of the simulation cases studies. The proposed PLS-WVCs are integrated with interval PLS (iPLS) further to select the informative wavelength intervals for spectroscopic modelling. The utility of the proposed WVC based variable selection methods in PLS is demonstrated with the real spectral data sets.
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- 2018
27. [New opportunities and challenges for hybrid data and model driven bioprocess optimization and scale-up]
- Author
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Guan, Wang, Xiwei, Tian, Jianye, Xia, Ju, Chu, Siliang, Zhang, and Yingping, Zhuang
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Bioreactors ,Fermentation ,Hydrodynamics ,Computer Simulation - Abstract
Currently, biomanufacturing technology and industry are receiving worldwide attention. However, there are still great challenges on bioprocess optimization and scale-up, including: lacing the process detection methods, which makes it difficult to meet the requirement of monitoring of key indicators and parameters; poor understanding of cell metabolism, which arouses problems to rationally achieve process optimization and regulation; the reactor environment is very different across the scales, resulting in low efficiency of stepwise scale-up. Considering the above key issues that need to be resolved, here we summarize the key technological innovations of the whole chain of fermentation process, i.e., real-time detection-dynamic regulation-rational scale-up, through case analysis. In the future, bioprocess design will be guided by a full lifecycle in-silico model integrating cellular physiology (spatiotemporal multiscale metabolic models) and fluid dynamics (CFD models). This will promote computer-aided design and development, accelerate the realization of large-scale intelligent production and serve to open a new era of green biomanufacturing.当前,生物制造技术和产业是世界关注的热点。然而,生物过程优化与放大过程中普遍面临以下几个难题,包括:过程检测手段缺乏,难以满足关键指标参数的监控;细胞代谢认知匮乏,无法理性实现过程最优化调控;反应器环境差异大,导致逐级放大效率低下。文中针对以上亟待解决的关键问题,通过案例分析介绍发酵过程实时检测-动态调控-理性放大全链条关键技术创新。在未来,生物过程设计将以集成细胞生理学 (时空多尺度细胞代谢模型) 和流体动力学 (CFD模型) 的全生命周期模型为指导,推进计算机辅助设计与开发,加速生物过程实现大规模智能化生产,开启绿色生物制造新时代。.
- Published
- 2021
28. Estimation Methods for Item Factor Analysis: An Overview
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Yunxiao Chen and Siliang Zhang
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Structure (mathematical logic) ,Multivariate statistics ,Computer science ,business.industry ,Machine learning ,computer.software_genre ,Set (abstract data type) ,Sample size determination ,Statistical inference ,Artificial intelligence ,business ,Categorical variable ,computer ,Factor analysis - Abstract
Item factor analysis (IFA) refers to the factor models and statistical inference procedures for analyzing multivariate categorical data. IFA techniques are commonly used in social and behavioral sciences for analyzing item-level response data. Such models summarize and interpret the dependence structure among a set of categorical variables by a small number of latent factors. In this chapter, we review the IFA modeling technique and commonly used IFA models. Then we discuss estimation methods for IFA models and their computation, with a focus on the situation where the sample size, the number of items, and the number of factors are all large. Existing statistical softwares for IFA are surveyed. This chapter is concluded with suggestions for practical applications of IFA methods and discussions of future directions.
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- 2021
29. Visualized podocyte-targeting and focused ultrasound responsive glucocorticoid nano-delivery system against immune-associated nephropathy without glucocorticoid side effect
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Jianwei Chen, Yan Zhao, Ling Zhong, Shuqin Xie, Yuan Yu, Siliang Zhang, Jing Guo, Qinyanqiu Xiang, Lan Hao, Li Zeng, Zhigang Wang, Qingyue Deng, Qin Zhou, Kui Fan, Yuanli Luo, and Jin Cao
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Male ,podocyte ,Side effect ,side effect ,Medicine (miscellaneous) ,dexamethasone ,Pharmacology ,Nephropathy ,Podocyte ,Rats, Sprague-Dawley ,Immune system ,Drug Delivery Systems ,In vivo ,medicine ,Animals ,Humans ,Receptor ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,Glucocorticoids ,Dexamethasone ,Cells, Cultured ,Ultrasonography ,Fluorocarbons ,business.industry ,Podocytes ,immune-associated nephropathy ,Imidazoles ,medicine.disease ,Rats ,stomatognathic diseases ,medicine.anatomical_structure ,nano-delivery system ,Creatinine ,Kidney Diseases ,business ,Receptor, Melanocortin, Type 1 ,Glucocorticoid ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,Research Paper - Abstract
Glucocorticoids are widely used in the treatment of nephritis, however, its dose-dependent side effects, such as the increased risk of infection and metabolic disturbances, hamper its clinical use. This study reports a visualized podocyte-targeting and focused ultrasound responsive glucocorticoid nano-delivery system (named as Dex/PFP@LIPs-BMS-α), which specific delivers dexamethasone (Dex) to podocyte targets and reduces systemic side effects. Methods: The glucocorticoid nano-delivery system was synthesized by a lipid thin film and a simple facile acoustic-emulsification method. This glucocorticoid nano-delivery system used BMS-470539 (BMS-α), a synthetic compound, as a "navigator" to specifically identify and target the melanocortin-1 receptor (MC-1R) on podocytes. The loaded perfluoropentane (PFP) realizes the directed "explosion effect" through ultrasound-targeted microbubble destruction (UTMD) technology under the coordination of low intensity focused ultrasound (LIFU) to completely release Dex. Results: Both in vitro and in vivo experiments have demonstrated that Dex/PFP@LIPs-BMs-α accurately gathered to podocyte targets and improved podocyte morphology. Moreover, in vivo, proteinuria and serum creatinine levels were significantly reduced in the group treated with Dex/PFP@LIPs-BMS-α, and no severe side effects were detected. Furthermore, Dex/PFP@LIPs-BMS-α, with capabilities of ultrasound, photoacoustic and fluorescence imaging, provided individualized visual guidance and the monitoring of treatment. Conclusion: This study provides a promising strategy of Dex/PFP@LIPs-BMS-α as effective and safe against immune-associated nephropathy.
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- 2020
30. Computation for Latent Variable Model Estimation: A Unified Stochastic Proximal Framework
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Siliang Zhang and Yunxiao Chen
- Subjects
Methodology (stat.ME) ,FOS: Computer and information sciences ,Likelihood Functions ,Psychometrics ,Applied Mathematics ,HA Statistics ,Computer Simulation ,Models, Theoretical ,Statistics - Computation ,Computation (stat.CO) ,General Psychology ,Algorithms ,Statistics - Methodology - Abstract
Latent variable models have been playing a central role in psychometrics and related fields. In many modern applications, the inference based on latent variable models involves one or several of the following features: (1) the presence of many latent variables, (2) the observed and latent variables being continuous, discrete, or a combination of both, (3) constraints on parameters, and (4) penalties on parameters to impose model parsimony. The estimation often involves maximizing an objective function based on a marginal likelihood/pseudo-likelihood, possibly with constraints and/or penalties on parameters. Solving this optimization problem is highly non-trivial, due to the complexities brought by the features mentioned above. Although several efficient algorithms have been proposed, there lacks a unified computational framework that takes all these features into account. In this paper, we fill the gap. Specifically, we provide a unified formulation for the optimization problem and then propose a quasi-Newton stochastic proximal algorithm. Theoretical properties of the proposed algorithms are established. The computational efficiency and robustness are shown by simulation studies under various settings for latent variable model estimation.
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- 2020
31. Efficacy and safety of hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI) on anemia in non-dialysis-dependent chronic kidney disease (NDD-CKD): a systematic review and meta-analysis
- Author
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Yuan Yu, Siliang Zhang, Shuqin Xie, Jianwei Chen, Jing Guo, and Shenrun Yu
- Subjects
Nephrology ,medicine.medical_specialty ,Anemia ,Urology ,030232 urology & nephrology ,030204 cardiovascular system & hematology ,Gastroenterology ,Hypoxia-Inducible Factor-Proline Dioxygenases ,03 medical and health sciences ,0302 clinical medicine ,Renal Dialysis ,Internal medicine ,medicine ,Humans ,Renal Insufficiency, Chronic ,Adverse effect ,biology ,Transferrin saturation ,business.industry ,medicine.disease ,Ferritin ,Treatment Outcome ,Meta-analysis ,biology.protein ,Hemoglobin ,business ,Kidney disease - Abstract
HIF-PHI (hypoxia-inducible factor prolyl hydroxylase inhibitor) was developed to improve renal anemia. This study was to evaluate the efficiency and safety of HIF-PHI in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD). The literature was extracted from PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and the Wanfang database. Statistical tests and forest plots were depicted by Review Manager Version 5.3. The primary outcome was a change in hemoglobin level from baseline (ΔHb). Secondary outcomes were changes in ferritin (ΔFerritin), hepcidin (ΔHepcidin), and transferrin saturation from baseline (ΔTSAT), and adverse events (AEs). This study is registered with PROSPERO (registration number CRD42020199656). Ten trials were included. The results showed that HIF-PHI improved the ΔHb [SMD 3.03 (95% CI 2.10, 3.96), P < 0.00001] in NDD patients. HIF-PHI reduced hepcidin levels in the NDD patients [SMD − 1.44 (95% CI − 2.19–0.70), P = 0.0002]. ΔFerritin values were reduced significantly in the HIF-PHI group [SMD − 1.08 (95% CI − 1.63–0.53), P = 0.0001]. However, ΔTSAT values showed no significant difference in the HIF-PHI group compared to the placebo group [SMD − 0.23 (95% CI − 0.66–0.21), P = 0.31]. In the safety assessment, HIF-PHI did not increase adverse events significantly [RR 0.98 (95% CI 0.88–1.10), P = 0.74]. HIF-PHI improves renal anemia and iron utilization disorder in NDD-CKD patients, without significantly more adverse events.
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- 2020
32. A latent Gaussian process model for analysing intensive longitudinal data
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Siliang Zhang and Yunxiao Chen
- Subjects
Statistics and Probability ,Time Factors ,BF Psychology ,Process (engineering) ,Normal Distribution ,Machine learning ,computer.software_genre ,01 natural sciences ,Structural equation modeling ,010104 statistics & probability ,Bayes' theorem ,symbols.namesake ,0504 sociology ,Arts and Humanities (miscellaneous) ,Borderline Personality Disorder ,Statistical inference ,Humans ,Psychology ,Computer Simulation ,HA Statistics ,Longitudinal Studies ,0101 mathematics ,Set (psychology) ,Gaussian process ,General Psychology ,Probability ,Fitness Trackers ,Depressive Disorder, Major ,Likelihood Functions ,Stochastic Processes ,Models, Statistical ,business.industry ,Estimation theory ,05 social sciences ,050401 social sciences methods ,Bayes Theorem ,General Medicine ,Affect ,Data Interpretation, Statistical ,symbols ,Artificial intelligence ,Dysthymic Disorder ,business ,computer ,Algorithms - Abstract
Intensive longitudinal studies are becoming progressively more prevalent across many social science areas, and especially in psychology. New technologies such as smart-phones, fitness trackers, and the Internet of Things make it much easier than in the past to collect data for intensive longitudinal studies, providing an opportunity to look deep into the underlying characteristics of individuals under a high temporal resolution. In this paper we introduce a new modelling framework for latent curve analysis that is more suitable for the analysis of intensive longitudinal data than existing latent curve models. Specifically, through the modelling of an individual-specific continuous-time latent process, some unique features of intensive longitudinal data are better captured, including intensive measurements in time and unequally spaced time points of observations. Technically, the continuous-time latent process is modelled by a Gaussian process model. This model can be regarded as a semi-parametric extension of the classical latent curve models and falls under the framework of structural equation modelling. Procedures for parameter estimation and statistical inference are provided under an empirical Bayes framework and evaluated by simulation studies. We illustrate the use of the proposed model though the analysis of an ecological momentary assessment data set.
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- 2020
33. Multi-scale data-driven engineering for biosynthetic titer improvement
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Weishan Wang, Zhixing Cao, Huifeng Wang, Qing Zhang, Hongzhong Lu, Lianqun Bao, Hui Xu, Xiuliang Yang, Xuekui Xia, Lixin Zhang, Siliang Zhang, and Jiaming Yu
- Subjects
0106 biological sciences ,0303 health sciences ,Computer science ,Process (engineering) ,Scale (chemistry) ,Biomedical Engineering ,Bioengineering ,Computational biology ,01 natural sciences ,Biosynthetic Pathways ,Metabolic engineering ,03 medical and health sciences ,Metabolic pathway ,Titer ,Bioreactors ,Metabolic Engineering ,010608 biotechnology ,Fermentation ,Bioreactor ,Process optimization ,Haystack ,Metabolic Networks and Pathways ,030304 developmental biology ,Biotechnology - Abstract
Industrial biosynthesis is a very complex process which depends on a range of different factors, from intracellular genes and metabolites, to extracellular culturing conditions and bioreactor engineering. The identification of species that improve the titer of some reaction is akin to the task of finding a needle in a haystack. This review aims to summarize state-of-the-art biosynthesis titer improvement on different scales separately, particularly regarding the advancement of metabolic pathway rewiring and data-driven process optimization and control. By integrating multi-scale data and establishing a mathematical replica of a real biosynthesis, more refined quantitative insights can be gained for achieving a higher titer than ever.
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- 2020
34. On stability analysis of cascaded linear time varying systems in dynamic isotope experiments
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Siliang Zhang, Weilu Lin, Zejian Wang, Yingping Zhuang, Mingzhi Huang, and Ju Chu
- Subjects
Environmental Engineering ,Isotope ,Chemistry ,General Chemical Engineering ,Biological system ,Stability (probability) ,Time complexity ,Biotechnology - Published
- 2020
35. Evaluation of an enclosed air-lift photobioreactor (ALPBR) for biomass and lipid biosynthesis of microalgal cells grown under fluid-induced shear stress
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Chao Li, Ning Ding, Tao Wang, Siliang Zhang, Ali Mohsin, and Meijin Guo
- Subjects
0106 biological sciences ,0303 health sciences ,Chemistry ,air-lift photobioreactor ,lcsh:Biotechnology ,lipid biosynthesis ,Photobioreactor ,01 natural sciences ,shear stress ,Lift (force) ,03 medical and health sciences ,Chemical engineering ,aeration rate ,Lipid biosynthesis ,microalgal growth ,lcsh:TP248.13-248.65 ,hydrodynamics ,Bioreactor ,Shear stress ,Aeration rate ,030304 developmental biology ,010606 plant biology & botany ,Biotechnology - Abstract
An enclosed air-lift photobioreactor (ALPBR) is considered an efficient lab-scale bioreactor for microalgae cell growth and lipid biosynthesis. However, fluid-induced shear stress and mixing are two main factors that affect physiological metabolism in microalgal cell cultures. Herein, a 50-L ALPBR after being designed and manufactured was evaluated for microalgal suspension culture. Moreover, computational fluid dynamics (CFD) simulation was used to characterize the hydrodynamics of ALPBR. Specifically, two model microalgae species Chlorella vulgaris and Chlorella protothecoides were cultured with aeration rates at 0.1, 0.2, 0.3, 0.4 volume per volume per minute (vvm). The hydrodynamics of ALPBR while considering shear rate, volume average velocity, turbulent energy dissipation rate (EDR), air volume fraction, and mean air bubble diameter, etc. showed that aeration generated a very low shear stress. When C. protothecoides and C. vulgaris were cultured with various aeration rates, the maximum dry cell weights (DCW) of two microalgal species tested were 0.3 vvm and 0.2 vvm, while the maximum lipid contents of both species were about 15.0% of the DCW, which were achieved at an air flow rate of 0.2 vvm. Therefore, we concluded that the shear rate generated by aeration could play a vital role in the cell growth of microalgae grown in an air-lift photobioreactor.
- Published
- 2020
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36. Determination of oroxylin A, oroxylin A 7-O-glucuronide, and oroxylin A sodium sulfonate in beagle dogs by using UHPLC MS/MS Application in a pharmacokinetic study
- Author
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Jiaming Li, Hui Yang, Yongjie Zhang, Guanghui Ren, Huili Chen, Zhongjin Song, Yang Lu, Siliang Zhang, Xiaoqian Wang, Shiyu Zhou, Mei Zhang, Nan Yang, Xijing Chen, Ning Li, Chuanru Xu, Di Zhao, and Chen Ning
- Subjects
Male ,Sodium ,Flavonoid ,chemistry.chemical_element ,Administration, Oral ,Filtration and Separation ,Tandem mass spectrometry ,01 natural sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Dogs ,Glucuronides ,Pharmacokinetics ,Tandem Mass Spectrometry ,Animals ,Tissue Distribution ,Chromatography, High Pressure Liquid ,chemistry.chemical_classification ,Flavonoids ,0303 health sciences ,Chromatography ,biology ,Molecular Structure ,030302 biochemistry & molecular biology ,010401 analytical chemistry ,biology.organism_classification ,Flavones ,0104 chemical sciences ,Sulfonate ,chemistry ,Injections, Intravenous ,Scutellaria baicalensis ,Oroxylin A ,Female ,Sulfonic Acids ,Quantitative analysis (chemistry) - Abstract
Oroxylin A, obtained from the root of Scutellaria baicalensis Georgi, is a flavonoid with antitumor and other pharmacological activities. Our previous studies showed for the first time that it is mainly metabolized to oroxylin A sodium sulfonate by sulfotransferase enzymes in beagle dogs. In this study, rapid, universal, selective, and robust ultra-high-performance liquid chromatography-tandem mass spectrometry methods were established and fully validated to quantitatively detect oroxylin A, oroxylin A 7-O-glucuronide, and oroxylin A sodium sulfonate in beagle dog plasma. The quantitative analysis for oroxylin A sodium sulfonate was reported for the first time. Plasma samples were processed with acetonitrile, a universal protein precipitant. Gradient elution was performed to resolve carryover effects and to achieve separation efficiency and sufficient chromatographic retention. The linear relationships of oroxylin A, oroxylin A 7-O-glucuronide, and oroxylin A sodium sulfonate in plasma were in the range of 2.0-500.0, 5.0-500.0, and 1.881-940.5 ng/mL, respectively. The assay method was successfully applied to pharmacokinetic study. This is the first paper that reveals the pharmacokinetic profile of oroxylin A, oroxylin A 7-O-glucuronide, and oroxylin A sodium sulfonate after single-dose intravenous and oral administration of Oroxylin A in beagle dogs.
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- 2019
37. Effective utilization of wastewater for valuable validamycin A biosynthesis by Streptomyces hygroscopicus K2509 in plant-scale bioreactor
- Author
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Li Zhang, Hua-Mei Liu, Xiwei Tian, Siliang Zhang, Wei Zou, Yingping Zhuang, Ali Mohsin, Meijin Guo, and Xiao-Hua Wang
- Subjects
Plant-scale bioreactor ,lcsh:Biotechnology ,Population ,Biomedical Engineering ,010501 environmental sciences ,Wastewater ,lcsh:Chemical technology ,01 natural sciences ,lcsh:Technology ,Validamycin A ,Tap water ,lcsh:TP248.13-248.65 ,Bioreactor ,lcsh:TP1-1185 ,education ,0105 earth and related environmental sciences ,education.field_of_study ,biology ,010405 organic chemistry ,Renewable Energy, Sustainability and the Environment ,lcsh:T ,biology.organism_classification ,Pulp and paper industry ,Environmentally friendly ,0104 chemical sciences ,Fermentation ,Environmental science ,Industrial and production engineering ,Streptomyces hygroscopicus ,Cost effective ,Food Science ,Biotechnology - Abstract
Background The continuous escalation in wastewater production with declining dependency on conventional resources as a result of rapid urbanization, increasing global water scarcity and growing population have initiated many researchers to look out for efficient means of utilizing wastewater. In this regard, an effectual process economizing approach has been achieved, upon utilizing the discharged wastewater from validamycin A recovery process in fermentation medium as a replacement of costly tap water. Results In this study, wastewater was successfully used as a fermentation medium for the production of validamycin A in plant-scale bioreactor. Moreover, a new strain Streptomyces hygroscopicus K2509 was screened showing a good production capability in this low-cost culture environment and showed maximum validamycin A production and productivity of 21.23 g/L and 0.29 g/L h, respectively. Execution of this study has managed the effective utilization of wastewater by reducing 12.42% production cost per kilogram of validamycin A in an environmental friendly way. Conclusion The novel successful approach for using process wastewater even on being executed in plant-scale bioreactor was proved cost effective. In short, the presented effective way of utilizing wastewater in study will definitely serve as potentially cheap fermentation medium upon replacing tremendously used expensive tap water.
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- 2018
38. Metabolite profiling coupled with metabolic flux analysis reveals physiological and metabolic impacts on Lactobacillus paracasei oxygen metabolism
- Author
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Yonghong Wang, Ju Chu, Xiwei Tian, Yingping Zhuang, and Siliang Zhang
- Subjects
0301 basic medicine ,chemistry.chemical_classification ,Reactive oxygen species ,Lactobacillus paracasei ,biology ,Acetoin ,030106 microbiology ,food and beverages ,Bioengineering ,Carbohydrate metabolism ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Biochemistry ,Lactic acid ,03 medical and health sciences ,chemistry.chemical_compound ,Enzyme ,chemistry ,Metabolic flux analysis ,Glycolysis - Abstract
In this study, the impacts of oxygen metabolism characterized by oxygen uptake rate (OUR) on lactic acid production in Lactobacillus paracasei were investigated through metabolite profiling and metabolic flux analysis. At growth phase, with the cost of declining lactic acid yield, the cells shifted pyruvate metabolism from lactic acid production to ATP high-yielding acetate synthesis to guarantee sufficient energy supply for cell growth under high OUR condition. When the cells reached to stationary phase, significant glucose metabolism inhibition happened with high OUR level due to much more reactive oxygen species (ROS) accumulation in the cells, which subsequently would attack glycolytic key enzyme, glycerate-3-phosphate dehydrogenase (GAPDH), leading to the substantial limitation of glucose consumption. Moreover, other than glucose metabolism restriction, the decline on metabolic level regulation of lactic acid yield further decreased lactic acid productivity. On the other hand, it was interestingly found that intracellular redox balance was greatly dependent on acetyl-CoA node (acetate/ethanol) in growth phase, and acetoin node (acetoin/2,3-butanediol) in stationary phase respectively. The application of integrated metabolite profiling and metabolic flux analysis highlighted the regulation of energy and redox metabolism in lactic acid production by L. paracasei.
- Published
- 2018
39. Application of 8-parallel micro-bioreactor system with non-invasive optical pH and DO biosensor in high-throughput screening of l-lactic acid producing strain
- Author
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Zhang Ming, Gang Zhou, Yingping Zhuang, Ju Chu, Ali Mohsin, Xiwei Tian, Wang Weifei, Haifeng Hang, and Siliang Zhang
- Subjects
0106 biological sciences ,0301 basic medicine ,Materials science ,Lactobacillus paracasei ,High-throughput screening ,lcsh:Biotechnology ,Biomedical Engineering ,Optical biosensor ,lcsh:Chemical technology ,complex mixtures ,01 natural sciences ,lcsh:Technology ,03 medical and health sciences ,chemistry.chemical_compound ,010608 biotechnology ,lcsh:TP248.13-248.65 ,Bioreactor ,lcsh:TP1-1185 ,Chromatography ,Strain (chemistry) ,biology ,Renewable Energy, Sustainability and the Environment ,lcsh:T ,technology, industry, and agriculture ,Lactic acid ,biology.organism_classification ,equipment and supplies ,Micro-bioreactor ,030104 developmental biology ,chemistry ,Yield (chemistry) ,Industrial and production engineering ,Biosensor ,Food Science ,Biotechnology - Abstract
Background Compared with shake flask, bioreactor offers a relatively stable and controllable extracellular environment for cell growth and metabolism. Meanwhile, parallel micro-bioreactor system could well meet the screening flux requirement in the process of high-throughput strain screening. In this study, a self-developed 8-parallel micro-bioreactor system with non-invasive optical biosensors was introduced to substitute the traditional shake flask. Results Optical pH and DO biosensors could be well applied for the process monitoring and controlling in the cultures of commonly used microorganisms through maintaining constant temperature and bioreactor shading treatment. Subsequently, 8-parallel micro-bioreactor system was adopted in the rescreening procedure of high-throughput screening process, and it significantly increased the feasibility of scaling up a cultivating system without any sacrifice on the screening flux. As a result, a designated mutant strain Lactobacillus paracasei S4 was obtained, which presented an improvement of 18.9% on titer value of l-lactic acid. Moreover, the yield also increased from 0.903 ± 0.005 to 0.932 ± 0.013 g/g. Conclusion In this study, the micro-bioreactor system proved to be applicable and effective in the rescreening procedure of high-throughput screening process. The adopted approach provided a robust tool for screening the strain with high l-lactic acid producing performance.
- Published
- 2018
40. MiR-99a Enhances the Radiation Sensitivity of Non-Small Cell Lung Cancer by Targeting mTOR
- Author
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Hongyu Ma, Siliang Zhang, Yu Zhang, Shiqi Piao, Yang Li, Qingyong Xu, Yuanyuan Qu, Hang Yin, Jianqun Ma, Xiaoyuan Wang, and Lin Chen
- Subjects
0301 basic medicine ,Lung Neoplasms ,Physiology ,Cell Survival ,Morpholines ,Transplantation, Heterologous ,Microrna-99a ,non-small cell lung cancer (NSCLC) ,Down-Regulation ,Mice, Nude ,Non-small cell lung cancer (NSCLC) ,Biology ,Radiation Tolerance ,lcsh:Physiology ,Radiosensitivity ,lcsh:Biochemistry ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Radiation sensitivity ,Radioresistance ,Carcinoma, Non-Small-Cell Lung ,Cell Line, Tumor ,microRNA ,Databases, Genetic ,medicine ,Animals ,Humans ,lcsh:QD415-436 ,3' Untranslated Regions ,Mammalian target of rapamycin (mTOR) ,PI3K/AKT/mTOR pathway ,lcsh:QP1-981 ,TOR Serine-Threonine Kinases ,Cancer ,Antagomirs ,Cell Cycle Checkpoints ,Cell cycle ,medicine.disease ,MicroRNAs ,030104 developmental biology ,Pyrimidines ,A549 Cells ,Gamma Rays ,030220 oncology & carcinogenesis ,Benzamides ,Cancer research ,Signal Transduction - Abstract
Background/Aims: Radiation therapy is an important and effective modality for the treatment of non-small cell lung cancer (NSCLC). MicroRNAs (miRNAs) are crucial post-transcriptional regulators that are involved in numerous important biologic processes. However, their potential involvement in radiation sensitivity remains unknown. Materials: We performed integrated analysis of miRNA expression in NSCLC using The Cancer Genome Atlas datasets. miR-99a was found to be significantly upregulated in cancer tissue and regulated cell survival. Cell culture was used to assess the role of miR-99a in radiation sensitivity. We then used flow cytometry to examine the effects of miR-99a on the cell cycle and apoptosis in cells exposed to radiation. To identify gene targets of miR-99a, a bioinformatics approach was adopted, and the findings of this analysis were verified using luciferase reporter assays. Finally, an in vivo study was conducted to examine the effect of miR-99a on tumor volume in an NSCLC mouse model undergoing radiation therapy. Results: miR-99a was significantly upregulated in radiation-sensitive A549 cells compared with radiation-resistant A549 cells. miR-99a overexpression was shown to enhance radiosensitivity, while inhibition of miR-99a resulted in radioresistance of NSCLC cell lines in vitro and in vivo. In addition, by bioinformatics software analysis and luciferase assays, mammalian target of rapamycin (mTOR) was identified as a direct target of miR-99a. Furthermore, AZD2014, an inhibitor of mTOR, enhanced radiosensitivity and apoptosis in NSCLC cell lines, while mTOR overexpression resulted in radioresistance and cell survival from miR-99a-induced cell apoptosis. Moreover, miR-99a overexpression further increased the efficacy of radiation therapy in an NSCLC xenograft mouse model, and miR-99a and mTOR expression was significantly inversely correlated. Conclusions: Altogether, these data suggested miR-99a functions as a tumor suppressor that has a critical role in regulating radiosensitivity of NSCLC by targeting the mTOR signaling pathway.
- Published
- 2018
41. Study on production enhancement of validamycin A using online capacitance measurement coupled with 1H NMR spectroscopy analysis in a plant-scale bioreactor
- Author
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Lan Li, Xiao-Hua Wang, Siliang Zhang, Hua-Mei Liu, Li Zhang, Yingping Zhuang, Kuipu Zhang, Meijin Guo, Ali Mohsin, and Wei Zou
- Subjects
0301 basic medicine ,Chromatography ,010401 analytical chemistry ,food and beverages ,Bioengineering ,Industrial fermentation ,Maltose ,Raw material ,01 natural sciences ,Applied Microbiology and Biotechnology ,Biochemistry ,Trehalose ,0104 chemical sciences ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Bioreactor ,Fermentation ,Sugar ,Flux (metabolism) - Abstract
Herein, an improved production of validamycin A was obtained upon developing a fed-batch strategy in a plant-scale bioreactor. The shift in metabolic flux during validamycin A fermentation process was elucidated using the online capacitance measurement coupled with 1H NMR spectroscopy. We found that the online capacitance measurement could replace DCW for biomass detection in raw material medium during fermentation. On the basis of cell mass and residual sugar concentration, a fed-batch fermentation strategy was developed, with two times addition of 12 g/L glucose in the broth at the 49.5th and 64.5th h. Subsequently, the validamycin A concentration reached 26.0 g/L in a 60-T fermenter. The intracellular concentration of trehalose, maltose, and tryptophan had notably increased, and their accumulation had a strong relationship with validamycin A production. In this study, a metabolomics analysis method without 13C labeling, which can be applied to plant-scale fermentation in turbid broth, is being presented for the first time. In brief, the undertaken study provides a new approach for the process improvement of validamycin A production.
- Published
- 2018
42. Comparative performance of different scale-down simulators of substrate gradients inPenicillium chrysogenumcultures: the need of a biological systems response analysis
- Author
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Amit T. Deshmukh, Joseph J. Heijnen, Jianye Xia, Henk J. Noorman, Yingping Zhuang, Ju Chu, Cees Haringa, Siliang Zhang, Junfei Zhao, Guan Wang, Wenjun Tang, and Walter M. van Gulik
- Subjects
0106 biological sciences ,0301 basic medicine ,Bioengineering ,Penicillins ,Penicillium chrysogenum ,01 natural sciences ,Applied Microbiology and Biotechnology ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Bioreactors ,Arabitol ,010608 biotechnology ,Bioreactor ,medicine ,Research Articles ,biology ,Strain (chemistry) ,Substrate (chemistry) ,biology.organism_classification ,Carbon ,Culture Media ,030104 developmental biology ,chemistry ,Fermentation ,Biophysics ,Carbohydrate Metabolism ,Mannitol ,Scale down ,Research Article ,Biotechnology ,medicine.drug - Abstract
In a 54 m3 large-scale penicillin fermentor, the cells experience substrate gradient cycles at the timescales of global mixing time about 20–40 s. Here, we used an intermittent feeding regime (IFR) and a two-compartment reactor (TCR) to mimic these substrate gradients at laboratory-scale continuous cultures. The IFR was applied to simulate substrate dynamics experienced by the cells at full scale at timescales of tens of seconds to minutes (30 s, 3 min and 6 min), while the TCR was designed to simulate substrate gradients at an applied mean residence time ((Formula presented.)) of 6 min. A biological systems analysis of the response of an industrial high-yielding P. chrysogenum strain has been performed in these continuous cultures. Compared to an undisturbed continuous feeding regime in a single reactor, the penicillin productivity (qPenG) was reduced in all scale-down simulators. The dynamic metabolomics data indicated that in the IFRs, the cells accumulated high levels of the central metabolites during the feast phase to actively cope with external substrate deprivation during the famine phase. In contrast, in the TCR system, the storage pool (e.g. mannitol and arabitol) constituted a large contribution of carbon supply in the non-feed compartment. Further, transcript analysis revealed that all scale-down simulators gave different expression levels of the glucose/hexose transporter genes and the penicillin gene clusters. The results showed that qPenG did not correlate well with exposure to the substrate regimes (excess, limitation and starvation), but there was a clear inverse relation between qPenG and the intracellular glucose level.
- Published
- 2018
43. Global transcriptional response of Aspergillus niger in the process of glucoamylase fermentation
- Author
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Li-feng liang, Geng-yun zhang, Yufei Sui, Ju Chu, Weiqiang Cao, Shu Cheng, Yingping Zhuang, Li-Ming Ouyang, Henk Norrman, and Siliang Zhang
- Subjects
0106 biological sciences ,0301 basic medicine ,lcsh:Biotechnology ,Asparagine synthetase ,Biomedical Engineering ,lcsh:Chemical technology ,01 natural sciences ,lcsh:Technology ,Transcriptome ,03 medical and health sciences ,chemistry.chemical_compound ,Biosynthesis ,010608 biotechnology ,lcsh:TP248.13-248.65 ,lcsh:TP1-1185 ,chemistry.chemical_classification ,biology ,Renewable Energy, Sustainability and the Environment ,lcsh:T ,Aspergillus niger ,Fatty acid ,Translation (biology) ,biology.organism_classification ,Amino acid ,030104 developmental biology ,chemistry ,Biochemistry ,Glucoamylase ,Metabolic pathways ,Oxygen limitation ,Fermentation ,Food Science ,Biotechnology - Abstract
Background In the phase of oxygen limitation during Aspergillus niger fermentation, the cell growth decreased, while the yield of glucoamylase increased continuously and significantly. Explanation on the changes of transcriptome profile during this process may improve our understanding on mechanisms of cell adaption and enzyme production in A. niger. Results The transcriptomic data from 4 time points in oxygen limitation process of a glucoamylase production A. niger strain were analyzed. Hierarchical clustering of all samples showed that the strongest transcriptional response occurred between the early and middle stage of oxygen limitation. 515 differentially expressed genes (DEGs) were identified and were clustered into 12 expression patterns. Continuously down-regulated DEGs were significantly enriched in GO terms of the ribosome, translation, and aminoacyl-tRNA biosynthesis, and continuously up-regulated DEGs were mainly involved in GO terms of fatty acid catabolism, N-acetyltransferase activity, lipase activity, and carboxylesterase activity. Pyruvate kinase and asparagine synthetase which related to the biosynthesis of the main amino acid composition of the enzyme were significantly up-regulated. Sterol-regulatory element-binding proteins (SREBP) transcription factor SrbB was one of the most up-regulated proteins, indicating its important roles in hypoxia fermentation of A. niger. Conclusion Comparative transcriptome data analysis of the fermentation revealed that the overall reduced biosynthesis of translation machine and fatty acid, acceleration of fatty acid catabolism, and increased synthesis of main amino acid compositions of glucoamylase are the key transcriptional changes during the oxygen limitation fermentation process of A. niger.
- Published
- 2017
44. Accurate Determination of Isotopic Abundance of Intracellular Metabolites of Saccharopolysporaerythraea Based on Ultra Performance Liquid Chromatography-Triple Quadrupole Mass Spectrometry
- Author
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Han Mou, Ju Chu, Mingzhi Huang, Ming Hong, Xiaoyun Liu, Min-Chao Li, Yingping Zhuang, and Siliang Zhang
- Subjects
0301 basic medicine ,chemistry.chemical_classification ,Sugar phosphates ,Chromatography ,biology ,Metabolite ,Analytical chemistry ,Natural abundance ,Mass spectrometry ,High-performance liquid chromatography ,Cofactor ,Analytical Chemistry ,Ion ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Quadrupole ,biology.protein - Abstract
A method was established for measuring 13C isotopic abundance of intracellular metabolites of Saccharopolysporaerythraea by ultra-high performance liquid chromatography (UPLC)-triple quadrupole mass spectrometry. Under the optimized chromatographic conditions of UPLC, and the appropriate and unique tube lens voltage, collision energy and ion pair, one-to-one method, one-to-many method and SIM method were established for measuring 13C isotopic abundance based on the length of the parent and daughter ions carbon chains and whether the daughter ions contain 13C atoms. The three methods were then applied to measure naturally labeled intracellular metabolite standards and 13C labeled samples. According to the gap between the experimental value and the theoretical value, the best method was found for each metabolite of different characteristics. The results showed that one-to-one method was the most effective for measuring the metabolites of daughter ions not containing 13C atoms represented by sugar phosphates, one-to-many method was the best for measuring the metabolites of both parent and daughter ions containing 13C short carbon chains represented by carboxylic acids, SIM method could played a role in measuring the metabolites of both parent and daughter ions containing 13C long carbon chains represented by coenzyme A. These methods had a good measurement precision and could be applied to the measurement of Saccharopolysporaerythraea intracellular metabolites, which would contribute to consequent study of the metabolic mechanism and the efficient expression of erythromycin.
- Published
- 2017
45. A novel strategy to dissect endogenous gene transcriptional regulation in live cells
- Author
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Siliang Zhang, Yi Zhang, Wenqing Yang, and Xin Huang
- Subjects
0301 basic medicine ,Therapeutic gene modulation ,GAL4/UAS system ,Transcription, Genetic ,Cell Survival ,Biophysics ,Biology ,Biochemistry ,Article ,03 medical and health sciences ,Humans ,E2F1 ,Molecular Biology ,Post-transcriptional regulation ,Regulator gene ,Regulation of gene expression ,Genetics ,Cell Cycle ,Nuclear Proteins ,Gene targeting ,Cell Biology ,High-Throughput Screening Assays ,Cell biology ,DNA-Binding Proteins ,MicroRNAs ,HEK293 Cells ,030104 developmental biology ,Gene Expression Regulation ,PAX4 ,DNA Damage ,Transcription Factors - Abstract
Gene transcription is a central tenet of biology, traditionally measured by RT-PCR, microarray, or more recently, RNA sequencing. However, these measurements only provide a snapshot of the state of gene transcription and only represent an overall readout of complex transcriptional networks that regulate gene expression. In this report, we describe a novel strategy to dissect endogenous gene transcription regulation in live cells by knocking in a reporter gene, EGFP, under the control of the endogenous gene promoter, using the ARID1A gene as an example. The ARID1A gene, encoding a subunit of the ATP-dependent chromatin remodeling complex SNF/SWI, has recently been identified as a tumor suppressor in multiple cancers. Despite studies that elucidate the mechanism of ARID1A‘s tumor suppressor function, little is known of the genes/events that regulate ARID1A expression. Using the HEK293 cells as a model, we discovered novel aspects of ARID1A transcription regulation in response to cell cycle progression, DNA damage, and microRNAs, exemplifying the potential of our strategy in providing new insight to the mechanism of gene transcription regulation. This strategy can be generalized to essentially any gene of interest, making it a powerful tool for the study of gene expression heterogeneity, especially in cancer cells, and a robust readout for high-throughput screening of agents that modulate gene transcription.
- Published
- 2017
46. Impact of postmastectomy radiation therapy in T1-2 breast cancer patients with 1-3 positive axillary lymph nodes
- Author
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Yuanyuan Qu, Hang Yin, Xueying Liu, Tengchuang Ma, Xiaoyuan Wang, Siliang Zhang, Qingyong Xu, Hongyu Ma, Enkang Xing, Haiyang Zhang, Yu Zhang, and Yang Li
- Subjects
Adult ,0301 basic medicine ,Oncology ,locoregional recurrence ,medicine.medical_specialty ,Axillary lymph nodes ,medicine.medical_treatment ,Breast Neoplasms ,surgery ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,Recurrence ,Internal medicine ,medicine ,Humans ,Risk factor ,Lymph node ,radiotherapy ,Mastectomy ,Survival analysis ,Neoplasm Staging ,Postoperative Care ,Proportional hazards model ,business.industry ,Middle Aged ,Prognosis ,medicine.disease ,Combined Modality Therapy ,Survival Analysis ,Surgery ,Radiation therapy ,Treatment Outcome ,030104 developmental biology ,medicine.anatomical_structure ,Lymphatic Metastasis ,030220 oncology & carcinogenesis ,Axilla ,Disease Progression ,Female ,Radiotherapy, Adjuvant ,Lymph Nodes ,business ,Research Paper - Abstract
The effect of postmastectomy radiotherapy (PMRT) on T1-2 breast cancer patients with 1-3 positive axillary lymph nodes is controversial up to now. The purpose of this study was to evaluate the impact of postmastectomy radiotherapy for these patients. The prognostic factor effecting locoregional free-survival (LRFS) was also analyzed. In the retrospective clinical data of 1674 eligible patients, survival analysis was performed using the method of Kaplan-Meier and the log-rank test. Cox regression analysis was applied to identify the significant prognostic factors. We found PMRT increased 5-year LRFS (p=0.003), but could not improve 5-year disease-free survival or overall survival statistically. For patients without PMRT, multivariate analysis revealed that age, lymph node ratio and molecule subtype were risk factors effecting LRFS. To further analyze the role of PMRT, we grouped all the patients into low risk group (0 or 1 risk factor) and high risk group (2 or 3 risk factors) depending on these risk factors. We found that in low-risk group, PMRT increased only 5-year LRFS (p=0.012). However, in high-risk group, PMRT increased both 5-year LRFS (p=0.005) and 5-year disease-free survival (p=0.033), but could not improve 5-year overall survival statistically. Thus, these data provide the evidence that PMRT could improve LRFS for T1-2 breast cancer patients with 1-3 positive axillary lymph nodes. Additionally, PMRT could improve LRFS and disease-free survival for high risk patients. Age, lymph node ratio and molecule subtype were high risk factors effecting LRFS in our study.
- Published
- 2017
47. [Progress in intelligent control of industrial bioprocess]
- Author
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Xiwei, Tian, Guan, Wang, Siliang, Zhang, and Yingping, Zhuang
- Subjects
Industrial Microbiology ,Bioreactors ,Fermentation ,Biotechnology - Abstract
Industrial bioprocess is a complex systematic process and bio-manufacturing can be realized on the basis of understanding the metabolism process of living cells. In this article, the multi-scale optimization principle and practice of industrial fermentation process are reviewed, including multi-scale optimizing theory and equipment, on-line sensing technology for cellular macroscopic metabolism, and correlated analysis of physiological parameters. Furthermore, intelligent control of industrial bioprocess is further addressed, in terms of new sensing technology for intracellular physiological metabolism, big database establishment and data depth calculation, intelligent decision.工业生物过程是一个复杂的系统过程,对活体细胞代谢过程的认识是实现高效工业生物制造的基础。文中首先综述了工业发酵过程多尺度优化控制原理和实践,包括多尺度理论与装备、细胞宏观代谢在线检测传感技术以及生理代谢参数相关分析。在此基础上,对工业生物过程智能控制——感知细胞内生理代谢特性新型传感技术、大数据库建立和数据深度计算以及生物过程智能决策进行了综述和展望。.
- Published
- 2019
48. Sertraline/ICG-loaded liposome for dual-modality imaging and effective chemo-photothermal combination therapy against metastatic clear cell renal cell carcinoma
- Author
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Jianwei Chen, Yuting Lei, Siliang Zhang, Wang Zhigang, Li Zeng, Ling Zhong, Fan Kui, Yuan Yu, and Shuqing Xie
- Subjects
Indocyanine Green ,Cell Membrane Permeability ,Combination therapy ,Drug Compounding ,Antineoplastic Agents ,Biocompatible Materials ,01 natural sciences ,Biochemistry ,chemistry.chemical_compound ,Nanocapsules ,Sertraline ,Drug Discovery ,Medicine ,Humans ,Carcinoma, Renal Cell ,Pharmacology ,010405 organic chemistry ,business.industry ,Organic Chemistry ,Optical Imaging ,Photothermal therapy ,medicine.disease ,Combined Modality Therapy ,Sertraline Hydrochloride ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Clear cell renal cell carcinoma ,Drug Liberation ,chemistry ,Photochemotherapy ,Drug delivery ,Cancer cell ,Liposomes ,Cancer research ,Molecular Medicine ,business ,Indocyanine green ,Clear cell - Abstract
A large number of chemotherapeutic drugs, utilized in the treatment of advanced metastatic clear cell renal cell carcinoma, are typically prone to poor biocompatibility, lack of targeting specificity, and high toxicity, which mostly leads to unsatisfactory clinical outcomes. As a new drug delivery pathway, nanoliposomes have the advantages of simplifying metabolism, reducing drug side-effects, and providing specific targeting, which can potentially improve the therapeutic effect toward tumor therapy. In this study, a clinically integrated nanoliposome containing Sertraline Hydrochloride and indocyanine green (ICG), here named as Ser/ICG@Lip, was successfully synthesized by film-dispersion and hydration-sonication methods. The photoacoustic imaging and near-infrared fluorescence imaging capabilities of this novel nanoliposome were validated in vitro. The high encapsulation rate of Sertraline Hydrochloride and ICG ensured the safety and therapeutic efficacy of the particle. Moreover, our results suggest that chemo-photothermal combination therapy can be more effective than single photothermal or chemotherapy treatments against malignant tumor cells. This is the first study introducing Sertraline Hydrochloride as a liposome-encapsulated chemotherapeutic agent, containing photothermal capabilities, for the treatment of metastatic renal clear cell cancer cells. This novel drug system has potential to evolve into an alternate treatment method for metastatic clear cell renal cell carcinoma.
- Published
- 2019
49. The application of deep learning framework in quantifying retinal structures on ophthalmic image in research eye-PACS
- Author
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Aimin Sang, Shenghui Zhao, Jiancheng Dong, Siliang Zhang, Moye Yu, Brent J. Liu, and Huiqun Wu
- Subjects
Pixel ,Computer science ,business.industry ,Deep learning ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Cognitive neuroscience of visual object recognition ,Construct (python library) ,Grayscale ,Object detection ,Segmentation ,Computer vision ,Artificial intelligence ,Medical diagnosis ,business - Abstract
The rise of deep learning (DL) framework and its application in object recognition could benefit image-based medical diagnosis. Since eye is believed to be a window into human health, the application of DL on differentiating abnormal ophthalmic photography (OP) will greatly empower ophthalmologists to relieve their workload for disease screening. In our previous work, we employed ResNet-50 to construct classification model for diabetic retinopathy(DR) within the PACS. In this study, we implemented latest DL object detection and semantic segmentation framework to empower the eye-PACS. Mask R-CNN framework was selected for object detection and instance segmentation of the optic disc (OD) and the macula. Furthermore, Unet framework was utilized for semantic segmentation of retinal vessel pixels from OP. The performance of the segmented results by two frameworks achieved state-of-art efficiency and the segmented results were transmitted to PACS as grayscale softcopy presentation state (GSPS) file. We also developed a prototype for OP quantitative analysis. It’s believed that the implementation of DL framework into the object recognition and analysis on OPs is meaningful and worth further investigation.
- Published
- 2019
50. Head and neck cancer radiation therapy decision support
- Author
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Brent J. Liu, Benjamin Yao, Siliang Zhang, Trent Benedick, Maying Shi, Anh H. Le, Veda Murthy, Rhea Koparde, and Sabrina Lieu
- Subjects
Radiation therapy ,DICOM ,Decision support system ,medicine.medical_specialty ,Workflow ,Imaging informatics ,Computer science ,medicine.medical_treatment ,Similarity (psychology) ,medicine ,Medical physics ,Radiation treatment planning ,Data-driven - Abstract
Currently the methods used to develop radiation therapy treatment plans for head and neck cancers rely on clinician experience and a small set of universal guidelines which result in inconsistent and variable methods. Data driven support can provide assistance to clinicians by reducing inconsistency associated with treatment planning and provide empirical estimates to minimize the radiation to healthy organs near the tumor. We created a database of DICOM RT objects which stores historical cases and when a new DICOM object is uploaded it will return a set of similar treatment plans to assist the clinician in creating the treatment plan for the current patient. The database works first by extracting features from DICOM RT object to quantitatively compare and evaluate the similarity of cases enabling the system to mine for cases with defined similarity. The feature extraction methods are based on the spatial relationships between the tumors and organs at risk which allows the generation the overlap volume histogram and spatial target similarity which demonstrate the volumetric and locational similarity between the organ at risk and the tumor. It is useful to find cases with similar tumor anatomy because this similarity translates to similarity in radiation dosage. The developed system was applied to three different RT sites, University of California Los Angeles, Technical University at Munich and State University of New York Buffalo; Roswell Park, with a total of 247 cases to evaluate the system for both inter- and intra- institutional best practices and results. Future roadmap will be discussed for correlating outcomes results to the decision support system which will enhance the overall performance and utilization of the decision support system in the RT workflow. In the future, because this database returns similar historical cases to a current one this could be a worthwhile decision support tool for clinicians as they create new radiation therapy treatment plans.
- Published
- 2019
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