1.Polysaccharide extract PCP1 from Polygonatum cyrtonema ameliorates cerebral ischemia-reperfusion injury in rats by inhibiting TLR4/NLRP3 pathway.
Xin ZHAN ; Zi-Xu LI ; Zhu YANG ; Jie YU ; Wen CAO ; Zhen-Dong WU ; Jiang-Ping WU ; Qiu-Yue LYU ; Hui CHE ; Guo-Dong WANG ; Jun HAN
China Journal of Chinese Materia Medica 2025;50(9):2450-2460
This study aims to investigate the protective effects and mechanisms of polysaccharide extract PCP1 from Polygonatum cyrtonema in ameliorating cerebral ischemia-reperfusion(I/R) injury in rats through modulation of the Toll-like receptor 4(TLR4)/NOD-like receptor protein 3(NLRP3) signaling pathway. In vivo, SD rats were randomly divided into the sham group, model group, PCP1 group, nimodipine(NMDP) group, and TLR4 signaling inhibitor(TAK-242) group. A middle cerebral artery occlusion/reperfusion(MCAO/R) model was established, and neurological deficit scores and infarct size were evaluated 24 hours after reperfusion. Hematoxylin-eosin(HE) and Nissl staining were used to observe pathological changes in ischemic brain tissue. Transmission electron microscopy(TEM) assessed ultrastructural damage in cortical neurons. Enzyme-linked immunosorbent assay(ELISA) was used to measure the levels of interleukin-1β(IL-1β), interleukin-6(IL-6), interleukin-18(IL-18), tumor necrosis factor-α(TNF-α), interleukin-10(IL-10), and nitric oxide(NO) in serum. Immunofluorescence was used to analyze the expression of TLR4 and NLRP3 proteins. In vitro, a BV2 microglial cell oxygen-glucose deprivation/reperfusion(OGD/R) model was established, and cells were divided into the control, OGD/R, PCP1, TAK-242, and PCP1 + TLR4 activator lipopolysaccharide(LPS) groups. The CCK-8 assay evaluated BV2 cell viability, and ELISA determined NO release. Western blot was used to analyze the expression of TLR4, NLRP3, and downstream pathway-related proteins. The results indicated that, compared with the model group, PCP1 significantly reduced neurological deficit scores, infarct size, ischemic tissue pathology, cortical cell damage, and the levels of inflammatory factors IL-1β, IL-6, IL-18, TNF-α, and NO(P<0.01). It also elevated IL-10 levels(P<0.01) and decreased the expression of TLR4 and NLRP3 proteins(P<0.05, P<0.01). Moreover, in vitro results showed that, compared with the OGD/R group, PCP1 significantly improved BV2 cell viability(P<0.05, P<0.01), reduced cell NO levels induced by OGD/R(P<0.01), and inhibited the expression of TLR4-related inflammatory pathway proteins, including TLR4, myeloid differentiation factor 88(MyD88), tumor necrosis factor receptor-associated factor 6(TRAF6), phosphorylated nuclear factor-kappaB dimer RelA(p-p65)/nuclear factor-kappaB dimer RelA(p65), NLRP3, cleaved-caspase-1, apoptosis-associated speck-like protein(ASC), GSDMD-N, IL-1β, and IL-18(P<0.05, P<0.01). The protective effects of PCP1 were reversed by LPS stimulation. In conclusion, PCP1 ameliorates cerebral I/R injury by modulating the TLR4/NLRP3 signaling pathway, exerting anti-inflammatory and anti-pyroptotic effects.
Animals
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Toll-Like Receptor 4/genetics*
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NLR Family, Pyrin Domain-Containing 3 Protein/genetics*
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Rats, Sprague-Dawley
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Rats
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Reperfusion Injury/genetics*
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Male
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Signal Transduction/drug effects*
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Polysaccharides/isolation & purification*
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Polygonatum/chemistry*
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Brain Ischemia/genetics*
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Drugs, Chinese Herbal/administration & dosage*
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Mice
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Humans
2.Expert consensus on the diagnosis and treatment of cemental tear.
Ye LIANG ; Hongrui LIU ; Chengjia XIE ; Yang YU ; Jinlong SHAO ; Chunxu LV ; Wenyan KANG ; Fuhua YAN ; Yaping PAN ; Faming CHEN ; Yan XU ; Zuomin WANG ; Yao SUN ; Ang LI ; Lili CHEN ; Qingxian LUAN ; Chuanjiang ZHAO ; Zhengguo CAO ; Yi LIU ; Jiang SUN ; Zhongchen SONG ; Lei ZHAO ; Li LIN ; Peihui DING ; Weilian SUN ; Jun WANG ; Jiang LIN ; Guangxun ZHU ; Qi ZHANG ; Lijun LUO ; Jiayin DENG ; Yihuai PAN ; Jin ZHAO ; Aimei SONG ; Hongmei GUO ; Jin ZHANG ; Pingping CUI ; Song GE ; Rui ZHANG ; Xiuyun REN ; Shengbin HUANG ; Xi WEI ; Lihong QIU ; Jing DENG ; Keqing PAN ; Dandan MA ; Hongyu ZHAO ; Dong CHEN ; Liangjun ZHONG ; Gang DING ; Wu CHEN ; Quanchen XU ; Xiaoyu SUN ; Lingqian DU ; Ling LI ; Yijia WANG ; Xiaoyuan LI ; Qiang CHEN ; Hui WANG ; Zheng ZHANG ; Mengmeng LIU ; Chengfei ZHANG ; Xuedong ZHOU ; Shaohua GE
International Journal of Oral Science 2025;17(1):61-61
Cemental tear is a rare and indetectable condition unless obvious clinical signs present with the involvement of surrounding periodontal and periapical tissues. Due to its clinical manifestations similar to common dental issues, such as vertical root fracture, primary endodontic diseases, and periodontal diseases, as well as the low awareness of cemental tear for clinicians, misdiagnosis often occurs. The critical principle for cemental tear treatment is to remove torn fragments, and overlooking fragments leads to futile therapy, which could deteriorate the conditions of the affected teeth. Therefore, accurate diagnosis and subsequent appropriate interventions are vital for managing cemental tear. Novel diagnostic tools, including cone-beam computed tomography (CBCT), microscopes, and enamel matrix derivatives, have improved early detection and management, enhancing tooth retention. The implementation of standardized diagnostic criteria and treatment protocols, combined with improved clinical awareness among dental professionals, serves to mitigate risks of diagnostic errors and suboptimal therapeutic interventions. This expert consensus reviewed the epidemiology, pathogenesis, potential predisposing factors, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of cemental tear, aiming to provide a clinical guideline and facilitate clinicians to have a better understanding of cemental tear.
Humans
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Dental Cementum/injuries*
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Consensus
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Diagnosis, Differential
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Cone-Beam Computed Tomography
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Tooth Fractures/therapy*
3.Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture-dislocation in adults (version 2025)
Qingde WANG ; Tongwei CHU ; Jian DONG ; Liangjie DU ; Haoyu FENG ; Shunwu FAN ; Shiqing FENG ; Yanzheng GAO ; Yong HAI ; Da HE ; Dianming JIANG ; Jianyuan JIANG ; Bin LIN ; Bin LIU ; Baoge LIU ; Fang LI ; Feng LI ; Li LI ; Weishi LI ; Fangcai LI ; Xiaoguang LIU ; Hongjian LIU ; Yong LIU ; Zhongjun LIU ; Shibao LU ; Xuhua LU ; Keya MAO ; Xuexiao MA ; Yong QIU ; Limin RONG ; Jun SHU ; Yueming SONG ; Tiansheng SUN ; Yan WANG ; Zhe WANG ; Zheng WANG ; Bing WANG ; Linfeng WANG ; Yu WANG ; Qinghe WANG ; Jigong WU ; Hong XIA ; Guoyong YIN ; Jinglong YAN ; Wen YUAN ; Yong YANG ; Qiang YANG ; Cao YANG ; Jie ZHAO ; Jianguo ZHANG ; Yue ZHU ; Zezhang ZHU ; Yingjie ZHOU ; Zhongmin ZHANG ; Yan ZENG ; Dingjun HAO ; Baorong HE ; Wei MEI
Chinese Journal of Trauma 2025;41(3):243-252
Cervical spinal cord injury without fracture-dislocation (CSCIWFD) is referred to as a special type of cervical spinal cord injury characterized by traumatic spinal cord dysfunction and no significant bony structural abnormalities on imagines. Duo to the high risk of missed diagnosis during the initial consultation, CSCIWFD may lead to progressive neurological deterioration or even complete paralysis, severely impacting patients′ prognosis. Currently, there are no established consensuses over the diagnosis and treatment of CSCIWFD, such as the lack of evidence-based standards for indications of non-surgical treatment and risk of secondary neurological injury, as well as debates over the optimal timing for surgical intervention and indications for different surgical approaches. To address these issues, the Spine Trauma Group of the Orthopedic Branch of the Chinese Medical Doctor Association organized experts in the relevant fields to formulate Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture- dislocation in adults ( version 2025) . Based on evidence-based medicine and the principles of scientific rigor and clinical applicability, the guidelines proposed 11 recommendations covering terminology, diagnosis, evaluation treatment, and rehabilitation, etc., aiming to standardize the management of CSCIWFD.
4.Difference of energy metabolism and skeletal muscle oxygenation in athletes under high temperature,high humidity and low oxygen environment
Zhizhong GENG ; Jinhao WANG ; Guohuan CAO ; Chenhao TAN ; Longji LI ; Jun QIU
Chinese Journal of Tissue Engineering Research 2025;29(32):6866-6876
BACKGROUND:Competitive athletes exercising in high-temperature,high-humidity,or low-oxygen environments experience intensified skeletal muscle deoxygenation and reduced fat oxidation,which can impair athletic performance.OBJECTIVE:To evaluate the impact of high-temperature,high-humidity,and low-oxygen environments on the fat oxidation rates of athletes during incremental load exercise,and to analyze the differences in deoxyhemoglobin kinetic parameters in skeletal muscle,thereby clarifying the relationship between fat oxidation capacity and skeletal muscle oxygenation under varying environmental conditions.METHODS:Twelve male modern pentathlon athletes were recruited for tests under three environmental conditions:normal(23 ℃,RH45%,FiO2=21.0%),high temperature and high humidity(35 ℃,RH70%,FiO2=21.0%),and low oxygen(23 ℃,RH45%,FiO2=15.6%).Resting metabolism and incremental load exercise were tested.Gas exchange data during and post-exercise were collected to calculate fat oxidation rate,carbohydrate oxidation rate,energy expenditure,and excess post-exercise oxygen consumption.Simultaneous measurements of SmO2 and total hemoglobin in the vastus lateralis muscle were used to calculate deoxyhemoglobin(HHb)levels.Deoxyhemoglobin change parameters-linear fittng slope(ΔEHHb),slope before the inflection point(ΔEHHB-1),and slope after the inflection point(ΔEHHB-2)-were determined using a bilinear function model.Fat oxidation curves were fitted using a SIN function model to identify the intensity(FATmax)that induced maximal fat oxidation(MFO),along with the curve's expansion,symmetry,and translation.RESULTS AND CONCLUSION:(1)Energy metabolism:No significant differences in maximal fat oxidation were observed across environments in each group(P>0.05).Compared with the normal environment group,both high temperature and high humidity group and low oxygen group showed significantly decreased time to maximal fat oxidation and FATmax(P<0.05).The percentage of maximal fat oxidation corresponding to peak oxygen uptake was lower in the low oxygen environment group(P<0.05).Fat oxidation was consistently low in the low oxygen environment group during exercise,while in the high temperature and high humidity environment group,it decreased only at higher exercise loads.Additionally,the expansion parameter was significantly reduced in both high temperature and high humidity and low oxygen environment groups(P<0.05).(2)Deoxyhemoglobin dynamics:The ΔEHHb was significantly higher in the high temperature and high humidity environment group,and ΔEHHB-1 was significantly increased in both high temperature and high humidity and low oxygen environment groups(P<0.05).(3)Correlation analysis:ΔEHHb was significantly negatively correlated with symmetry;ΔEHHB-1 was negatively correlated with FATmax and maximal fat oxidation;ΔEHHB-2 was positively correlated with maximal fat oxidation,and V?O2@BP was positively correlated with symmetry,expansion,and FATmax.(4)These findings indicate that incremental load exercise in high temperature,high humidity,and low oxygen environments accelerates skeletal muscle deoxygenation,thereby inhibiting fat oxidation capacity.Compared with high temperature and high humidity,low oxygen environments may more rapidly disrupt the balance between oxygen delivery and utilization in athletes'skeletal muscle,leading to a greater reliance on anaerobic glycolysis and a consequent reduction in fat oxidation capacity during exercise.
5.Difference of energy metabolism and skeletal muscle oxygenation in athletes under high temperature,high humidity and low oxygen environment
Zhizhong GENG ; Jinhao WANG ; Guohuan CAO ; Chenhao TAN ; Longji LI ; Jun QIU
Chinese Journal of Tissue Engineering Research 2025;29(32):6866-6876
BACKGROUND:Competitive athletes exercising in high-temperature,high-humidity,or low-oxygen environments experience intensified skeletal muscle deoxygenation and reduced fat oxidation,which can impair athletic performance.OBJECTIVE:To evaluate the impact of high-temperature,high-humidity,and low-oxygen environments on the fat oxidation rates of athletes during incremental load exercise,and to analyze the differences in deoxyhemoglobin kinetic parameters in skeletal muscle,thereby clarifying the relationship between fat oxidation capacity and skeletal muscle oxygenation under varying environmental conditions.METHODS:Twelve male modern pentathlon athletes were recruited for tests under three environmental conditions:normal(23 ℃,RH45%,FiO2=21.0%),high temperature and high humidity(35 ℃,RH70%,FiO2=21.0%),and low oxygen(23 ℃,RH45%,FiO2=15.6%).Resting metabolism and incremental load exercise were tested.Gas exchange data during and post-exercise were collected to calculate fat oxidation rate,carbohydrate oxidation rate,energy expenditure,and excess post-exercise oxygen consumption.Simultaneous measurements of SmO2 and total hemoglobin in the vastus lateralis muscle were used to calculate deoxyhemoglobin(HHb)levels.Deoxyhemoglobin change parameters-linear fittng slope(ΔEHHb),slope before the inflection point(ΔEHHB-1),and slope after the inflection point(ΔEHHB-2)-were determined using a bilinear function model.Fat oxidation curves were fitted using a SIN function model to identify the intensity(FATmax)that induced maximal fat oxidation(MFO),along with the curve's expansion,symmetry,and translation.RESULTS AND CONCLUSION:(1)Energy metabolism:No significant differences in maximal fat oxidation were observed across environments in each group(P>0.05).Compared with the normal environment group,both high temperature and high humidity group and low oxygen group showed significantly decreased time to maximal fat oxidation and FATmax(P<0.05).The percentage of maximal fat oxidation corresponding to peak oxygen uptake was lower in the low oxygen environment group(P<0.05).Fat oxidation was consistently low in the low oxygen environment group during exercise,while in the high temperature and high humidity environment group,it decreased only at higher exercise loads.Additionally,the expansion parameter was significantly reduced in both high temperature and high humidity and low oxygen environment groups(P<0.05).(2)Deoxyhemoglobin dynamics:The ΔEHHb was significantly higher in the high temperature and high humidity environment group,and ΔEHHB-1 was significantly increased in both high temperature and high humidity and low oxygen environment groups(P<0.05).(3)Correlation analysis:ΔEHHb was significantly negatively correlated with symmetry;ΔEHHB-1 was negatively correlated with FATmax and maximal fat oxidation;ΔEHHB-2 was positively correlated with maximal fat oxidation,and V?O2@BP was positively correlated with symmetry,expansion,and FATmax.(4)These findings indicate that incremental load exercise in high temperature,high humidity,and low oxygen environments accelerates skeletal muscle deoxygenation,thereby inhibiting fat oxidation capacity.Compared with high temperature and high humidity,low oxygen environments may more rapidly disrupt the balance between oxygen delivery and utilization in athletes'skeletal muscle,leading to a greater reliance on anaerobic glycolysis and a consequent reduction in fat oxidation capacity during exercise.
6.Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture-dislocation in adults (version 2025)
Qingde WANG ; Tongwei CHU ; Jian DONG ; Liangjie DU ; Haoyu FENG ; Shunwu FAN ; Shiqing FENG ; Yanzheng GAO ; Yong HAI ; Da HE ; Dianming JIANG ; Jianyuan JIANG ; Bin LIN ; Bin LIU ; Baoge LIU ; Fang LI ; Feng LI ; Li LI ; Weishi LI ; Fangcai LI ; Xiaoguang LIU ; Hongjian LIU ; Yong LIU ; Zhongjun LIU ; Shibao LU ; Xuhua LU ; Keya MAO ; Xuexiao MA ; Yong QIU ; Limin RONG ; Jun SHU ; Yueming SONG ; Tiansheng SUN ; Yan WANG ; Zhe WANG ; Zheng WANG ; Bing WANG ; Linfeng WANG ; Yu WANG ; Qinghe WANG ; Jigong WU ; Hong XIA ; Guoyong YIN ; Jinglong YAN ; Wen YUAN ; Yong YANG ; Qiang YANG ; Cao YANG ; Jie ZHAO ; Jianguo ZHANG ; Yue ZHU ; Zezhang ZHU ; Yingjie ZHOU ; Zhongmin ZHANG ; Yan ZENG ; Dingjun HAO ; Baorong HE ; Wei MEI
Chinese Journal of Trauma 2025;41(3):243-252
Cervical spinal cord injury without fracture-dislocation (CSCIWFD) is referred to as a special type of cervical spinal cord injury characterized by traumatic spinal cord dysfunction and no significant bony structural abnormalities on imagines. Duo to the high risk of missed diagnosis during the initial consultation, CSCIWFD may lead to progressive neurological deterioration or even complete paralysis, severely impacting patients′ prognosis. Currently, there are no established consensuses over the diagnosis and treatment of CSCIWFD, such as the lack of evidence-based standards for indications of non-surgical treatment and risk of secondary neurological injury, as well as debates over the optimal timing for surgical intervention and indications for different surgical approaches. To address these issues, the Spine Trauma Group of the Orthopedic Branch of the Chinese Medical Doctor Association organized experts in the relevant fields to formulate Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture- dislocation in adults ( version 2025) . Based on evidence-based medicine and the principles of scientific rigor and clinical applicability, the guidelines proposed 11 recommendations covering terminology, diagnosis, evaluation treatment, and rehabilitation, etc., aiming to standardize the management of CSCIWFD.
7.Effect of high-fat diet intake on pharmacokinetics of amoxicillin and clavulanate potassium tablet in healthy Chinese volunteers
Yu-Fang XU ; Hao-Jing SONG ; Bo QIU ; Yi-Ting HU ; Wan-Jun BAI ; Xue SUN ; Bin CAO ; Zhan-Jun DONG
The Chinese Journal of Clinical Pharmacology 2024;40(4):589-593
Objective To observe the pharmacokinetic effect of amoxicillin and clavulanate potassium tablets on amoxicillin in Chinese healthy subjects under fasting and high fat and high calorie diet.Methods 71 healthy subjects were given a single dose of amoxicillin potassium clavulanate tablets(0.375 g)on fasting or high fat diet,and venous blood samples were collected at different time points.The concentrations of amoxicillin in human plasma were determined by HPLC-MS/MS method,and the pharmacokinetic parameters were calculated by non-atrioventricular model using PhoenixWinNonlin 8.0 software.Results The main pharmacokinetic parameters of amoxicillin potassium clavulanate tablets after fasting and high fat diet were(5 105.00±1 444.00),(4 593.00±1 327.00)ng·mL-1,and postprandial-fasting ratio 89.40%,90%confidence interval(79.55%-100.19%);t1/2 were(1.52±0.16),(1.39±0.22)h;AUC0-t were(12 969.00±1 841.00),(11 577.00±1 663.00)ng·mL-1·h,and postdietary/fasting ratio 89.20%,90%confidence interval(83.92%-94.28%);AUC0-∞ were(13 024.00±1 846.00),(11 532.00±1 545.00)ng·mL-1·h,and postprandial-fasting ratio 88.60%,90%confidence interval(83.48%-93.50%).The median Tmax(range)were 1.63(0.75,3.00)and 2.50(0.75,6.00)h,respectively,and the Tmax of postprandial medication was delayed(P<0.01).Conclusion Compared with fasting condition,amoxicillin Tmax was significantly delayed after high fat diet,while Cmax,AUC0-t and AUC0-∞ were not significantly changed,indicating that food could delay the absorption of amoxicillin,but did not affect the degree of absorption.
8.Pathological Characteristics and Classification of Unstable Coronary Atheroscle-rotic Plaques
Yun-Hong XING ; Yang LI ; Wen-Zheng WANG ; Liang-Liang WANG ; Le-Le SUN ; Qiu-Xiang DU ; Jie CAO ; Guang-Long HE ; Jun-Hong SUN
Journal of Forensic Medicine 2024;40(1):59-63
Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart dis-ease,such as acute or chronic myocardial ischemic changes,sometimes make it difficult to locate the ischemic site due to the short death process,the lack of tissue reaction time.In some cases,the de-ceased died of sudden death on the first-episode,resulting in difficulty for medical examiners to make an accurate diagnosis.However,clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process.This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medi-cal research,including plaque rupture,plaque erosion and calcified nodules,as well as the influencing factors leading to plaque instability,and briefly describes the research progress and technique of the atherosclerotic plaques,in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different patho-logic states of coronary atherosclerotic plaques.
9.Clinical Characteristics and Survival Analysis of Carbapenem-Resistant Pseudomonas Aeruginosa Colonized or Infected Patients with Hematological Disorders.
Ying-Ying SHEN ; Yue-Chao ZHAO ; Bo WANG ; Di-Jiong WU ; Qiu-Shuang LI ; Yi-Ping SHEN ; Jian-Ping SHEN ; Jun-Min CAO ; Sheng-Yun LIN ; Bao-Dong YE
Journal of Experimental Hematology 2023;31(4):1192-1198
OBJECTIVE:
To observe the clinical characteristics and impact on mortality of carbapenem-resistant Pseudomonas aeruginosa (CRPA) colonized or infected patients with hematological disorders in order to provide evidence for the prevention and treatment of CRPA.
METHODS:
The patients who were colonized or infected with CRPA in the Department of Hematology of The First Affiliated Hospital of Zhejiang Chinese Medical University from January 2020 to March 2021 were selected as the research subjects, the clinical data such as hospitalization time, primary disease treatment regimen, granulocyte count, previous infection and antibiotic regimen of these patients were analyzed, meanwhile, antibiotic regimen and efficacy during CRPA infection, 30-day and long-term survival were also analyzed.
RESULTS:
A total of 59 patients were included in this study, and divided into CRPA infection group (43 cases) and CRPA colonization group (16 cases). Univariate logistic regression analysis showed that ECOG score (P =0.003), agranulocytosis (P <0.001), and exposure to upper than 3rd generations of cephalosporins and tigecycline within 30 days (P =0.035, P =0.017) were the high-risk factors for CRPA infection. Multivariate logistic regression analysis showed that ECOG score of 3/4 ( OR=10.815, 95%CI: 1.260-92.820, P =0.030) and agranulocytosis ( OR=13.82, 95%CI: 2.243-85.176, P =0.005) were independent risk factors for CRPA infection. There was a statistically significant difference in cumulative survival rate between CRPA colonization group and CRPA infection group ( χ2=14.134, P < 0.001). Kaplan-Meier survival analysis showed that the influencing factors of 30-day survival in patients with CRPA infection were agranulocytosis (P =0.022), soft tissue infection (P =0.03), and time of hospitalization before CRPA infection (P =0.041). Cox regression analysis showed that agranulocytosis was an independent risk factor affecting 30-day survival of patients with CRPA infection (HR=3.229, 95%CI :1.093-3.548, P =0.034).
CONCLUSIONS
Patients with hematological disorders have high mortality and poor prognosis after CRPA infection. Bloodstream infection and soft tissue infection are the main causes of death. Patients with high suspicion of CRPA infection and high-risk should be treated as soon as possible.
Humans
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Carbapenems/therapeutic use*
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Pseudomonas aeruginosa
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Soft Tissue Infections/drug therapy*
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Anti-Bacterial Agents/therapeutic use*
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Hematologic Diseases
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Survival Analysis
10.Semi-rational evolution of ω-transaminase from Aspergillus terreus for enhancing the thermostability.
Tingting CAI ; Jiaren CAO ; Shuai QIU ; Changjiang LYU ; Fangfang FAN ; Sheng HU ; Weirui ZHAO ; Lehe MEI ; Jun HUANG
Chinese Journal of Biotechnology 2023;39(6):2126-2140
ω-transaminase (ω-TA) is a natural biocatalyst that has good application potential in the synthesis of chiral amines. However, the poor stability and low activity of ω-TA in the process of catalyzing unnatural substrates greatly hampers its application. To overcome these shortcomings, the thermostability of (R)-ω-TA (AtTA) from Aspergillus terreus was engineered by combining molecular dynamics simulation assisted computer-aided design with random and combinatorial mutation. An optimal mutant AtTA-E104D/A246V/R266Q (M3) with synchronously enhanced thermostability and activity was obtained. Compared with the wild- type (WT) enzyme, the half-life t1/2 (35 ℃) of M3 was prolonged by 4.8-time (from 17.8 min to 102.7 min), and the half deactivation temperature (T1050) was increased from 38.1 ℃ to 40.3 ℃. The catalytic efficiencies toward pyruvate and 1-(R)-phenylethylamine of M3 were 1.59- and 1.56-fold that of WT. Molecular dynamics simulation and molecular docking showed that the reinforced stability of α-helix caused by the increase of hydrogen bond and hydrophobic interaction in molecules was the main reason for the improvement of enzyme thermostability. The enhanced hydrogen bond of substrate with surrounding amino acid residues and the enlarged substrate binding pocket contributed to the increased catalytic efficiency of M3. Substrate spectrum analysis revealed that the catalytic performance of M3 on 11 aromatic ketones were higher than that of WT, which further showed the application potential of M3 in the synthesis of chiral amines.
Transaminases/chemistry*
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Molecular Docking Simulation
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Amines/chemistry*
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Pyruvic Acid/metabolism*
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Enzyme Stability

Result Analysis
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