1.Development of an artificial intelligence-based automatic MRI scoring model for extramural vascular invasion in rectal cancer and its prognostic value
Haitao HUANG ; Yunrui YE ; Lifen YAN ; Yanfen CUI ; Lili FENG ; Huifen YE ; Yulin LIU ; Ying ZHU ; Zhongwei CHEN ; Zhenhui LI ; Ke ZHAO ; Zaiyi LIU ; Changhong LIANG
Chinese Journal of Radiology 2025;59(11):1267-1274
Objective:To develop an artificial intelligence (AI)-based automatic scoring model for magnetic resonance imaging-detected extramural vascular invasion (AI-mrEMVI) and evaluate its performance and prognostic value in patients with rectal cancer.Methods:In this multicenter retrospective cohort study, a total of 2 501 rectal cancer patients from seven centers between November 2012 and December 2020 were included and divided into completely independent training ( n=1 830) and validation ( n=671) cohorts. A nnUNet-based AI-mrEMVI scoring model was constructed. Manual mrEMVI scores assigned by two radiologists served as the reference standard for accessing the accuracy of the AI-mrEMVI scoring. Kaplan-Meier survival analysis and Cox regression were used to evaluate the prognostic stratification ability of the AI-mrEMVI scores. The concordance index (C-index) was calculated to evaluate prognostic performance. Results:In the validation cohort, the manual mrEMVI scores were 0-2 in 425 patients (63.3%), 3 in 89 (13.4%), and 4 in 157 (23.4%). The AI-mrEMVI model identified 0-2 in 375 patients (55.9%), 3 in 95 (14.2%), and 4 in 201 (30.0%), with an overall accuracy of 81.1% (544/671, 95% CI 77.9%-84.0%). The 3-year disease-free survival (DFS) rates for patients with AI-mrEMVI scores of 0-2, 3, and 4 were 85.2%, 70.0%, and 58.2%, respectively, and the 5-year overall survival (OS) rates were 87.2%, 81.6%, and 62.6%, respectively (DFS: χ2=48.74, P<0.001; OS: χ2=30.04, P<0.001). Multivariable Cox regression showed that for DFS, AI-mrEMVI scores of 3 and 4 were associated with hazard ratios ( HR) of 1.75 (95% CI 1.11-2.77, P=0.016) and 2.65 (95% CI 1.86-3.78, P<0.001), respectively. For OS, an AI-mrEMVI score of 4 was associated with an HR of 2.56 (95% CI 1.62-4.03, P<0.001). The C-index values of the AI-mrEMVI scoring model for predicting DFS and OS were 0.647 (95% CI 0.608-0.686) and 0.650 (95% CI 0.598-0.702), respectively. Conclusion:The proposed AI-mrEMVI automatic scoring model demonstrated high diagnostic accuracy and performed favorably in predicting DFS and OS prognostic risk in patients with rectal cancer.
2.Effect of tirofiban on prognosis in acute anterior circulation large vessel occlusion stroke patients with unsuccessful recanalization after endovascular treatment
Anyu LIAO ; Minxing ZHAO ; Kang YUAN ; Kangmo HUANG ; Zhiliang GUO ; Xianjun HUANG ; Zhenhui DUAN ; Rui LIU ; Guodong XIAO ; Wenhua LIU ; Zhiming ZHOU ; Wusheng ZHU
Chinese Journal of Cerebrovascular Diseases 2025;22(8):515-523,578
Objective To analyze the effects of intravenous tirofiban following endovascular treatment on the prognosis of patients with acute anterior circulation large vessel occlusion stroke who did not achieve successful recanalization.Methods This retrospective study included consecutive patients with acute anterior circulation ischemic stroke who underwent endovascular treatment but did not achieve successful recanalization.These patients were retrospectively enrolled from the Department of Neurology at Nanjing Jinling Hospital,Affiliated Hospital of Medical School,Nanjing University,the Second Affiliated Hospital of Soochow University,Wuhan No.1 Hospital,and Yijishan Hospital of Wannan Medical College(the First Affiliated Hospital of Wannan Medical College)between January 2015 and April 2023.Baseline and clinical data were collected including age,sex,medical history(hypertension,diabetes,atrial fibrillation,hyperlipidemia),personal history(smoking and drinking),National Institutes of Health stroke scale(NIHSS)score at admission,trial of Org 10172 in acute stroke treatment(TOAST)classification(large artery atherosclerosis,cardioembolism,or other types),Alberta stroke program early CT score(ASPECTS)on admission,intravenous thrombolysis,onset-to-puncture time(OTP),collateral circulation status(poor collaterals:American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology[ASTIN/SIR]score 0-2;good collateral:ASTIN/SIR score 3-4),procedure duration(from femoral or radial artery puncture to device removal),occlusion site,number of passes for thrombus retrieval,and post-procedural modified thrombolysis in cerebral infarction(mTICI)grade.Patients were divided into a tirofiban group and a non-tirofiban group based on whether they received post-procedural intravenous tirofiban.The primary outcome is a favorable functional outcome at 90-day since onset(modified Rankin scale[mRS]score ≤ 3).Safety outcomes included mortality at 90-day since onset(mRS score 6),any intracranial hemorrhage within 24 h post-procedure,and symptomatic intracranial hemorrhage within 24 h post-procedure.1∶1 propensity score matchings using the nearest neighbor method was performed based on variables with P<0.05 in the comparison between the tirofiban and non-tirofiban groups.Differences in primary and safety outcomes between the matched groups were compared.Univariate and multivariate Logistic regression analyses were conducted with favorable outcomes at 90 days as the dependent variable to evaluate the effect of intravenous tirofiban administration after endovascular therapy on 90-day prognosis in patients without successful recanalization.Results A total of 356 patients without successful recanalization after endovascular treatment were included,comprising 195 males and 161 females,with a median age of 70(61,78)years(32-92 years).Among them,76 and 280patients were assigned to the tirofiban and non-tirofiban groups,respectively.At 90 days,114 patients had favorable outcomes,while 242 had unfavorable outcomes.(1)Before the 1∶1 propensity score matching,significant differences were observed between the tirofiban and non-tirofiban groups in terms of admission NIHSS score,ASPECTS,good collateral circulation,intravenous thrombolysis,and mTICI grade(all P<0.05).After 1∶1 propensity score matching,66 matched pairs(132 patients)were obtained.No significant differences in the baseline and clinical characteristics were found between the two groups after matching(all P>0.05).(2)After 1∶1 matching,a significant difference was observed in the rate of favorable outcomes at 90 days between the two groups(48.5%[32/66]vs.30.3%[20/66],P=0.033)after propensity score matching,while no significant differences were found in 90-day mortality,intracranial hemorrhage within 24h,or symptomatic intracranial hemorrhage within 24h(all P>0.05).(3)Univariate analysis after 1∶1 matching indicated that age,atrial fibrillation,smoking history,admission NIHSS score,M2 segment middle cerebral artery occlusion,good collateral circulation,number of passes for thrombus retrieval,and tirofiban treatment were factors influencing favorable outcomes at 90 days.Multivariate Logistic regression analysis showed that younger age(aOR,0.942,95%CI 0.906-0.978,P=0.002),lower admission NIHSS score(aOR,0.855,95%CI 0.777-0.941,P=0.001),good collateral circulation(aOR,5.534,95%CI 2.141-14.301,P<0.01),tirofiban treatment(aOR,2.774,95%CI 1.092-7.046,P=0.032),and M2 segment MCA occlusion(reference:internal carotid artery occlusion;aOR,4.874,95%CI 1.428-16.632,P=0.011)were independent predictors of favorable outcomes at 90 days.Conclusions Intravenous tirofiban administration after endovascular therapy may improve 90-day neurological outcomes in patients with acute anterior circulation large vessel occlusion stroke who did not achieve successful recanalization without increasing the risk of hemorrhage.Further large-scale randomized controlled trials are warranted to validate these findings.
3.Effect of tirofiban on prognosis in acute anterior circulation large vessel occlusion stroke patients with unsuccessful recanalization after endovascular treatment
Anyu LIAO ; Minxing ZHAO ; Kang YUAN ; Kangmo HUANG ; Zhiliang GUO ; Xianjun HUANG ; Zhenhui DUAN ; Rui LIU ; Guodong XIAO ; Wenhua LIU ; Zhiming ZHOU ; Wusheng ZHU
Chinese Journal of Cerebrovascular Diseases 2025;22(8):515-523,578
Objective To analyze the effects of intravenous tirofiban following endovascular treatment on the prognosis of patients with acute anterior circulation large vessel occlusion stroke who did not achieve successful recanalization.Methods This retrospective study included consecutive patients with acute anterior circulation ischemic stroke who underwent endovascular treatment but did not achieve successful recanalization.These patients were retrospectively enrolled from the Department of Neurology at Nanjing Jinling Hospital,Affiliated Hospital of Medical School,Nanjing University,the Second Affiliated Hospital of Soochow University,Wuhan No.1 Hospital,and Yijishan Hospital of Wannan Medical College(the First Affiliated Hospital of Wannan Medical College)between January 2015 and April 2023.Baseline and clinical data were collected including age,sex,medical history(hypertension,diabetes,atrial fibrillation,hyperlipidemia),personal history(smoking and drinking),National Institutes of Health stroke scale(NIHSS)score at admission,trial of Org 10172 in acute stroke treatment(TOAST)classification(large artery atherosclerosis,cardioembolism,or other types),Alberta stroke program early CT score(ASPECTS)on admission,intravenous thrombolysis,onset-to-puncture time(OTP),collateral circulation status(poor collaterals:American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology[ASTIN/SIR]score 0-2;good collateral:ASTIN/SIR score 3-4),procedure duration(from femoral or radial artery puncture to device removal),occlusion site,number of passes for thrombus retrieval,and post-procedural modified thrombolysis in cerebral infarction(mTICI)grade.Patients were divided into a tirofiban group and a non-tirofiban group based on whether they received post-procedural intravenous tirofiban.The primary outcome is a favorable functional outcome at 90-day since onset(modified Rankin scale[mRS]score ≤ 3).Safety outcomes included mortality at 90-day since onset(mRS score 6),any intracranial hemorrhage within 24 h post-procedure,and symptomatic intracranial hemorrhage within 24 h post-procedure.1∶1 propensity score matchings using the nearest neighbor method was performed based on variables with P<0.05 in the comparison between the tirofiban and non-tirofiban groups.Differences in primary and safety outcomes between the matched groups were compared.Univariate and multivariate Logistic regression analyses were conducted with favorable outcomes at 90 days as the dependent variable to evaluate the effect of intravenous tirofiban administration after endovascular therapy on 90-day prognosis in patients without successful recanalization.Results A total of 356 patients without successful recanalization after endovascular treatment were included,comprising 195 males and 161 females,with a median age of 70(61,78)years(32-92 years).Among them,76 and 280patients were assigned to the tirofiban and non-tirofiban groups,respectively.At 90 days,114 patients had favorable outcomes,while 242 had unfavorable outcomes.(1)Before the 1∶1 propensity score matching,significant differences were observed between the tirofiban and non-tirofiban groups in terms of admission NIHSS score,ASPECTS,good collateral circulation,intravenous thrombolysis,and mTICI grade(all P<0.05).After 1∶1 propensity score matching,66 matched pairs(132 patients)were obtained.No significant differences in the baseline and clinical characteristics were found between the two groups after matching(all P>0.05).(2)After 1∶1 matching,a significant difference was observed in the rate of favorable outcomes at 90 days between the two groups(48.5%[32/66]vs.30.3%[20/66],P=0.033)after propensity score matching,while no significant differences were found in 90-day mortality,intracranial hemorrhage within 24h,or symptomatic intracranial hemorrhage within 24h(all P>0.05).(3)Univariate analysis after 1∶1 matching indicated that age,atrial fibrillation,smoking history,admission NIHSS score,M2 segment middle cerebral artery occlusion,good collateral circulation,number of passes for thrombus retrieval,and tirofiban treatment were factors influencing favorable outcomes at 90 days.Multivariate Logistic regression analysis showed that younger age(aOR,0.942,95%CI 0.906-0.978,P=0.002),lower admission NIHSS score(aOR,0.855,95%CI 0.777-0.941,P=0.001),good collateral circulation(aOR,5.534,95%CI 2.141-14.301,P<0.01),tirofiban treatment(aOR,2.774,95%CI 1.092-7.046,P=0.032),and M2 segment MCA occlusion(reference:internal carotid artery occlusion;aOR,4.874,95%CI 1.428-16.632,P=0.011)were independent predictors of favorable outcomes at 90 days.Conclusions Intravenous tirofiban administration after endovascular therapy may improve 90-day neurological outcomes in patients with acute anterior circulation large vessel occlusion stroke who did not achieve successful recanalization without increasing the risk of hemorrhage.Further large-scale randomized controlled trials are warranted to validate these findings.
4.Development of an artificial intelligence-based automatic MRI scoring model for extramural vascular invasion in rectal cancer and its prognostic value
Haitao HUANG ; Yunrui YE ; Lifen YAN ; Yanfen CUI ; Lili FENG ; Huifen YE ; Yulin LIU ; Ying ZHU ; Zhongwei CHEN ; Zhenhui LI ; Ke ZHAO ; Zaiyi LIU ; Changhong LIANG
Chinese Journal of Radiology 2025;59(11):1267-1274
Objective:To develop an artificial intelligence (AI)-based automatic scoring model for magnetic resonance imaging-detected extramural vascular invasion (AI-mrEMVI) and evaluate its performance and prognostic value in patients with rectal cancer.Methods:In this multicenter retrospective cohort study, a total of 2 501 rectal cancer patients from seven centers between November 2012 and December 2020 were included and divided into completely independent training ( n=1 830) and validation ( n=671) cohorts. A nnUNet-based AI-mrEMVI scoring model was constructed. Manual mrEMVI scores assigned by two radiologists served as the reference standard for accessing the accuracy of the AI-mrEMVI scoring. Kaplan-Meier survival analysis and Cox regression were used to evaluate the prognostic stratification ability of the AI-mrEMVI scores. The concordance index (C-index) was calculated to evaluate prognostic performance. Results:In the validation cohort, the manual mrEMVI scores were 0-2 in 425 patients (63.3%), 3 in 89 (13.4%), and 4 in 157 (23.4%). The AI-mrEMVI model identified 0-2 in 375 patients (55.9%), 3 in 95 (14.2%), and 4 in 201 (30.0%), with an overall accuracy of 81.1% (544/671, 95% CI 77.9%-84.0%). The 3-year disease-free survival (DFS) rates for patients with AI-mrEMVI scores of 0-2, 3, and 4 were 85.2%, 70.0%, and 58.2%, respectively, and the 5-year overall survival (OS) rates were 87.2%, 81.6%, and 62.6%, respectively (DFS: χ2=48.74, P<0.001; OS: χ2=30.04, P<0.001). Multivariable Cox regression showed that for DFS, AI-mrEMVI scores of 3 and 4 were associated with hazard ratios ( HR) of 1.75 (95% CI 1.11-2.77, P=0.016) and 2.65 (95% CI 1.86-3.78, P<0.001), respectively. For OS, an AI-mrEMVI score of 4 was associated with an HR of 2.56 (95% CI 1.62-4.03, P<0.001). The C-index values of the AI-mrEMVI scoring model for predicting DFS and OS were 0.647 (95% CI 0.608-0.686) and 0.650 (95% CI 0.598-0.702), respectively. Conclusion:The proposed AI-mrEMVI automatic scoring model demonstrated high diagnostic accuracy and performed favorably in predicting DFS and OS prognostic risk in patients with rectal cancer.
5.Construction and practice of intelligent management mode for hospital clinical research based on collaborative governance
Bingwei WANG ; Liang MA ; Ruoyan HAN ; Changpeng LIU ; Yuan WANG ; Zhenhui LIU ; Yongfeng CHEN ; Mingming ZHAO ; Yan ZHENG ; Yanyan LIU
Chinese Journal of Hospital Administration 2024;40(9):666-671
Promoting the transformation and development of public hospitals into clinical research-oriented hospitals is the necessary way for China to deepen the reform of medicine and health system. In August 2019, Henan Cancer Hospital deeply combined the key elements of clinical research management with the concept of multidisciplinary collaborative governance, created an offline operating end of collaborative governance (including the front collaborative recruitment system, the middle collaborative quality management system, and the terminal collaborative transformation system), built a supporting internet plus intelligent auxiliary end (including the intelligent recruitment manager, the intelligent quality manager and the intelligent transformation manager), and built a clinical research intelligent management mode covering the trinity of subject recruitment, clinical research quality control, and innovation achievements transformation. The hospital focused on management elements such as " focusing on quality, improving efficiency, and increasing motivation" , and drove the front, middle, and terminal ends of the model to work together, to ensure the quality and efficiency of clinical research and achieve a comprehensive improvement in the hospital′s clinical research level. As of December 2023, the hospital had undertaken over 2 000 clinical research projects of various types, with a cumulative amount of clinical research conversion contracts exceeding 53 million yuan. This practice had achieved good results and could provided references for other tertiary public hospitals to promote high-quality development of clinical research.
6.Automated Echocardiographic Measurement of Left Ventricular Ejection Fraction Based on Foundation Model in Computer Vision
Xintong WU ; Xiaolin DIAO ; Qi ZHAO ; Jiahui GENG ; Xiaoyuan GAO ; Zixing WANG ; Xin QUAN ; Zhenhui ZHU ; Wei ZHAO
Chinese Circulation Journal 2024;39(11):1092-1097
Objectives:To examine the feasibility of using foundation model in computer vision for echocardiographic left ventricular ejection fraction measurement. Methods:Based on the most extensive publicly accessible repository of echocardiographic loops,EchoNet-Dynamic,featuring 10024 recordings from individual patients,a foundation model in computer vision,VideoMAE V2,was fine-tuned,validated,tested using 7460,1288,and 1276 echocardiographic loops,respectively. Results:The mean absolute error between left ventricular ejection fraction measurements of VideoMAE V2 and expert's measurements was 3.94% (95%CI:3.79%-4.11%).The Pearson's correlation coefficient was 0.91 (95%CI:0.89-0.92).Additionally,VideoMAE V2 demonstrated exceptional accuracy in identifying patients with a left ventricular ejection fraction below 50%,achieving an AUC of 0.96 (95%CI:0.95-0.97). Conclusions:This study validates the feasibility of using foundation model in computer vision for measuring left ventricular ejection fraction in echocardiographic loops and lays the foundation for the development of a generalized multimodal automated interpretation system for echocardiography.
7.Artificial intelligence-based analysis of tumor-infiltrating lymphocyte spatial distribution for colorectal cancer prognosis
Ming CAI ; Ke ZHAO ; Lin WU ; Yanqi HUANG ; Minning ZHAO ; Qingru HU ; Qicong CHEN ; Su YAO ; Zhenhui LI ; Xinjuan FAN ; Zaiyi LIU
Chinese Medical Journal 2024;137(4):421-430
Background::Artificial intelligence (AI) technology represented by deep learning has made remarkable achievements in digital pathology, enhancing the accuracy and reliability of diagnosis and prognosis evaluation. The spatial distribution of CD3 + and CD8 + T cells within the tumor microenvironment has been demonstrated to have a significant impact on the prognosis of colorectal cancer (CRC). This study aimed to investigate CD3 CT (CD3 + T cells density in the core of the tumor [CT]) prognostic ability in patients with CRC by using AI technology. Methods::The study involved the enrollment of 492 patients from two distinct medical centers, with 358 patients assigned to the training cohort and an additional 134 patients allocated to the validation cohort. To facilitate tissue segmentation and T-cells quantification in whole-slide images (WSIs), a fully automated workflow based on deep learning was devised. Upon the completion of tissue segmentation and subsequent cell segmentation, a comprehensive analysis was conducted.Results::The evaluation of various positive T cell densities revealed comparable discriminatory ability between CD3 CT and CD3-CD8 (the combination of CD3 + and CD8 + T cells density within the CT and invasive margin) in predicting mortality (C-index in training cohort: 0.65 vs. 0.64; validation cohort: 0.69 vs. 0.69). The CD3 CT was confirmed as an independent prognostic factor, with high CD3 CT density associated with increased overall survival (OS) in the training cohort (hazard ratio [HR] = 0.22, 95% confidence interval [CI]: 0.12–0.38, P <0.001) and validation cohort (HR = 0.21, 95% CI: 0.05–0.92, P = 0.037). Conclusions::We quantify the spatial distribution of CD3 + and CD8 + T cells within tissue regions in WSIs using AI technology. The CD3 CT confirmed as a stage-independent predictor for OS in CRC patients. Moreover, CD3 CT shows promise in simplifying the CD3-CD8 system and facilitating its practical application in clinical settings.
8.Traditional Chinese Medicine Regulates Oxidative Stress-related Signaling Pathways to Prevent and Treat Bronchial Asthma: A Review
Xuyang ZHENG ; Zhenhui SHU ; Yi LI ; Ziyue QU ; Weilin LI ; Kexin MA ; Junsheng SHA ; Limin ZHAO
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(18):260-269
Bronchial asthma (asthma for short) is a common clinical respiratory disease mainly characterized by chronic airway inflammation, with complicated pathogenesis and a long treatment cycle. It is lingering and difficult to be cured, and lack specific drugs. Oxidative stress is a new focus in the research on the pathogenesis of asthma and a potential key target for the treatment. Under physiological conditions, the oxidative and antioxidative systems in the body are in a dynamic balance, and the two antagonize each other to maintain normal life activities. In the case of asthma attack, oxidation products such as reactive oxygen species (ROS), malondialdehyde (MDA), and nitric oxide (NO) are produced excessively, while the content of antioxidants such as superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) is reduced. As a result, the oxidation exceeds the removal of oxidation products, which aggravates oxidative stress. In addition, the overproduction of ROS activates oxidative stress-related signaling pathways to produce pro-inflammatory factors, exacerbating inflammation, which leads to lung and airway tissue damage. In recent years, traditional Chinese medicine has garnering increasing attention because of the unique advantages in the treatment of asthma, especially in regulating redox balance, alleviating oxidative stress in asthma patients, and reducing inflammation. On the one hand, by inhibiting the mitogen-activated protein kinase (MAPK) and transcription factor (NF)-κB signaling pathways, traditional Chinese medicine can reduce the content of oxidation products and pro-inflammatory factors from the source. On the other hand, by activating the nuclear factor-erythroid 2-related factor 2 (NrF2) signaling pathway, traditional Chinese medicine can elevate the levels of antioxidant enzymes and enhance the antioxidant system to neutralize the excessive accumulation of oxidation products. Therefore, the adjustment of redox balance state by traditional Chinese medicine may be a new means and a new direction for the prevention and treatment of asthma in the future. This paper summarizes the oxidative stress-related pathways in the pathogenesis of asthma and reviews the latest research progress in the regulation of oxidative stress-related pathways by Chinese medicine extracts and prescriptions in the treatment of asthma, with a view to providing a fuller, more solid, and more scientific theoretical basis for the clinical and basic research on the prevention and treatment of asthma by traditional Chinese medicine.
9.Current status of asphyxia prevention and management for the elderly in 43 elderly care institutions
Zhenhui WANG ; Naixue CUI ; Jie ZHAO ; Liguo QIN ; Wenting XIE ; Jinfeng JIA ; Chao SUN
Chinese Journal of Modern Nursing 2021;27(29):3972-3976
Objective:To explore the current situation and related factors of asphyxia prevention and management for the elderly in elderly care institutions, so as to provide a reference for improving the safety management of elderly care institutions.Methods:This research was a cross-sectional survey. From December 2020 to January 2021, convenience sampling was used to select 43 elderly care institutions from the China Aged Care Alliance. The self-designed questionnaire was used to collect the content related to asphyxia prevention and management for the elderly in institutions, and analyze its current situation and related factors. A total of 43 questionnaires were distributed in this survey, and 43 were recovered, with a recovery rate of 100%.Results:Among the 43 elderly care institutions, and 3 (6.98%) were state-run, and 22 (51.16%) were private, and 18 (41.86%) were public and private. The average occupancy rate was (67.63±20.59) %, and the average proportion of moderate to severe disability among the elderly residents was (80.10±20.25) %. The proportions of elderly care institutions that formulated systems and regulations for monitoring and early warning of asphyxia events, reporting of asphyxia events, analysis and improvement of asphyxia incidents in the elderly were 53.49%, 51.16%, and 51.16%, respectively. The proportions of elderly care institutions that carried out asphyxia risk screening, swallowing function assessment, and swallowing function training for the elderly residents were 65.12%, 51.16%, and 46.51%, respectively.Conclusions:Most elderly care institutions have problems in the prevention and management of asphyxia for the elderly, which needs to be improved. It is recommended that building a complete asphyxia prevention and management system, carrying out risk screening, assessment and training of swallowing function for high-risk groups, strengthening the professional training of agency leaders and caregivers, and seeking continuous external professional support so as to improve the safety management system of elderly care institutions, and ensure the quality of life and personal safety of the elderly.
10.Synthesis of pyrroloquinoline quinone by recombinant Gluconobacter oxydans.
Runle YE ; Feng LI ; Fan DING ; Zhenhui ZHAO ; Sheng CHEN ; Jianfeng YUAN
Chinese Journal of Biotechnology 2020;36(6):1138-1149
Pyrroloquinoline quinone (PQQ), an important redox enzyme cofactor, has many physiological and biochemical functions, and is widely used in food, medicine, health and agriculture industry. In this study, PQQ production by recombinant Gluconobacter oxydans was investigated. First, to reduce the by-product of acetic acid, the recombinant strain G. oxydans T1 was constructed, in which the pyruvate decarboxylase (GOX1081) was knocked out. Then the pqqABCDE gene cluster and tldD gene were fused under the control of endogenous constitutive promoter P0169, to generate the recombinant strain G. oxydans T2. Finally, the medium composition and fermentation conditions were optimized. The biomass of G. oxydans T1 and G. oxydans T2 were increased by 43.02% and 38.76% respectively, and the PQQ production was 4.82 and 20.5 times higher than that of the wild strain, respectively. Furthermore, the carbon sources and culture conditions of G. oxydans T2 were optimized, resulting in a final PQQ yield of (51.32±0.899 7 mg/L), 345.6 times higher than that of the wild strain. In all, the biomass of G. oxydans and the yield of PQQ can be effectively increased by genetic engineering.
Fermentation
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Gene Knockout Techniques
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Gluconobacter oxydans
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genetics
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metabolism
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Industrial Microbiology
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methods
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Multigene Family
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genetics
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Organisms, Genetically Modified
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PQQ Cofactor
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biosynthesis
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genetics
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Promoter Regions, Genetic
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genetics

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