1.Distribution characteristics of pathogens and influencing factors analysis of infections within 90 days after liver transplantation
Huabin PENG ; Haofeng XIONG ; Fei HOU ; Shuang ZHAO ; Yizhi ZHANG ; Tingting CUI ; Zhiying HE ; Jingyi LIU ; Liying SUN
Organ Transplantation 2026;17(2):212-226
Objective To investigate the distribution characteristics of pathogens causing infections within 90 days after liver transplantation and the influencing factors of infection. Methods Clinical data of 176 recipients who underwent liver transplantation at the Liver Transplant Center of Beijing Friendship Hospital Affiliated to Capital Medical University from September 2021 to August 2024 were retrospectively analyzed. Patients were divided into the infection group (n=124) and the non-infection group (n=52) based on whether they developed infection within 90 days after transplantation. The distribution characteristics of pathogens in infected patients were analyzed. Univariate and multivariate logistic regression analyses were used to explore the influencing factors of infection. Results Among the 176 liver transplant recipients, 124 cases developed 243 episodes of 518 bacterial, fungal, viral or mycoplasma infections within 90 days after transplantation, with an overall infection rate of 70.5% (124/176). The composition of pathogens was mainly Gram-negative bacteria (38.6%, 200/518), followed by Gram-positive bacteria (32.2%, 167/518) and viruses (15.4%, 80/518), and fungi accounted for 13.1% (68/518). Among Gram-negative bacteria, the main pathogen was Klebsiella pneumoniae (6.8%, 35/518), and among Gram-positive bacteria, the main pathogen was Enterococcus faecalis (8.5%, 44/518). Viruses included Epstein-Barr virus (3.7%, 19/518) and cytomegalovirus (3.7%, 19/518), and fungi were mainly Candida albicans (6.8%, 35/518). The most common infection site among the 243 episodes was pulmonary infection (42.0%, 102/243), followed by abdominal infection (22.6%, 55/243) and bloodstream infection (18.1%, 44/243). The infections mainly occurred within 2 weeks after transplantation (60.9%, 148/243). Multivariate logistic regression analysis indicated that preoperative infection within 2 weeks, a high preoperative model for end-stage liver disease (MELD) score, and preoperative sarcopenia were independent risk factors for infection within 90 days after liver transplantation (all odds ratio>1, P<0.05). After multivariate correction, the levels of CD4+T cells and CD8+T cells within 90 days after surgery were independently associated with the occurrence of infection. Low levels of CD4+T cells and CD8+T cells might be related to an increased risk of infection. Conclusions The infection rate after liver transplantation is high, and the pathogens are mainly Gram-negative bacteria. The lungs are the most common infection site. Preoperative MELD score, preoperative sarcopenia and preoperative infection within 2 weeks are independent risk factors for infection within 90 days after liver transplantation. Regular monitoring of immune indicators CD4+T cells and CD8+T cells levels after transplantation is helpful to reduce the occurrence of post-transplantation infection.
2.Huanglian Jiedutang Improves Cognitive Impairment after Schemic Stroke by Regulating Neuron via NF-κB Signaling Pathway
Mengying SUN ; Lizhen WANG ; Tong LI ; Leilei WANG ; Shiyan JIA ; Tingting WANG ; Yanwen YANG ; Kaiqiang SI ; Youxiang CUI ; Zhilong LIU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(11):68-76
ObjectiveTo investigate the effects of Huanglian Jiedutang (HLJDT) on cognitive function in mice with ischemic stroke (IS) and to elucidate whether its neuroprotective effects are mediated by inhibition of the nuclear factor-κB (NF-κB) signaling pathway and subsequent suppression of NF-κB-regulated neuronal apoptosis. MethodsAn IS model was established using middle cerebral artery occlusion (MCAO). Sixty C57BL/6J mice were randomly assigned to five groups (n =12 per group), i.e., sham operation, model, HLJDT low-dose (3.9 g·kg-1·d-1), HLJDT high-dose (7.8 g·kg-1·d-1), and Ginkgo biloba extract (GBE, 31.2 mg·kg-1·d-1). Post-operatively, neurological deficit scores (Longa score), cerebral infarct volume assessed by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and brain water content were evaluated. Learning and memory were assessed using new object recognition (NOR) and fear conditioning (FC) tests. Hippocampal pathology was examined via hematoxylin and eosin (HE) staining. Immunofluorescence detected expression of glial fibrillary acidic protein (GFAP, astrocyte marker), cellular oncogene Fos (c-Fos, neuronal activation marker), and glutamate decarboxylase 65 (GAD65). Western blot measured nuclear factor-κB inhibitor protein α (IκBα), phosphorylated IκBα (p-IκBα), NF-κB p65, phosphorylated NF-κB p65 (p-NF-κB p65), ionic calcium binding adapter molecule 1 (Iba-1), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and apoptosis-related proteins, such as cleaved cysteinyl aspartate-specific protease 3 (Caspase-3), B-cell lymphoma 2 (Bcl-2), and Bcl-2-associated X protein (Bax). Real-time quantitative PCR (Real-time PCR) was used to assess mRNA levels of Iba-1, TNF-α, IL-1β, NF-κB p65, cleaved Caspase-3, Bax, and Bcl-2. ResultsCompared with the sham group, the model group exhibited significantly increased neurological deficit scores, brain water content, and cerebral infarct volume (P<0.01). Hippocampal CA1 neurons were disorganized, showing nuclear pyknosis and karyolysis. NOR exploration time and FC freezing time were significantly reduced (P<0.01). GFAP and c-Fos expression were increased, while GAD65 expression was decreased (P<0.01). Cleaved Caspase-3 and Bax were upregulated, Bcl-2 was downregulated, and the Bax/Bcl-2 ratio was elevated (P<0.01). Expression levels of p-IκBα, p-NF-κB p65, IL-1β, TNF-α, and Iba-1 were significantly increased (P<0.01). Compared with the model group, HLJDT high-dose, low-dose, and GBE groups showed significant improvements in all parameters (P<0.01). Among them, the HLJDT high-dose group showed the most pronounced neuronal structural recovery and superior performance in NOR and FC tests (P<0.01). In this group, GFAP and c-Fos decreased, GAD65 increased (P<0.01), apoptosis-related protein expression was reversed, and NF-κB signaling and related inflammatory factor expression were suppressed (P<0.01). ConclusionHLJDT ameliorates cognitive dysfunction in mice after IS, potentially by inhibiting the NF-κB signaling pathway, thereby reducing neuroinflammation and hippocampal neuronal apoptosis.
3.Mechanism of Wendan Ningxin Granules in Modulating Diastolic Calcium Leakage-related Proteins to Improve Inflammation-associated Atrial Fibrillation Susceptibility
Biyue SHANG ; Tingting ZHU ; Shunxin LYU ; Zhiwei ZHANG ; Yufei WANG ; Xiangning CUI ; Yingdong LU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(11):133-143
ObjectiveTo investigate the protective effect and mechanism of Wendan Ningxin granules (WNG) on susceptibility to atrial fibrillation (AF) in mice with inflammatory injury. Methods100 C57BL/6 mice were divided into a blank control group, a model group, a low-dose WNG group (2.34 g·kg-1·d-1), a high-dose WNG group (4.68 g·kg-1·d-1), and an amiodarone positive control group (0.091 g·kg-1·d-1), with 20 mice in each group. Except for the blank control group, mice in other groups received intraperitoneal injections of lipopolysaccharide (LPS) to establish an inflammatory injury model. Treatment groups received continuous intragastric administration of their respective interventions for four weeks. During the fourth week, the treatment groups received LPS injections concurrently with their treatments. The blank control and model groups received distilled water (10 mL·kg-1·d-1) by gavage, with a gavage volume of 10 mL·kg-1 for all groups, once daily. Hematoxylin-eosin (HE) staining and Sirius red staining were used to observe atrial tissue morphology and fibrosis degree. Immunohistochemistry was used to assess the expression of α-smooth muscle actin (α-SMA) in mouse atrial tissue. Electrophysiological detection was performed using a multi-channel electrophysiology mapping system to measure AF inducibility, AF duration, and atrial effective refractory period (AERP). High-resolution optical mapping was used to measure action potential duration (APD) dispersion, conduction heterogeneity index, and calcium transient (CaT) dispersion. Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect mRNA expression of proteins related to diastolic calcium leakage in mouse atria: Ca2+/calmodulin-dependent protein kinase Ⅱ(CaMKⅡ), ryanodine receptor 2(RyR2), sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA), and sodium-calcium exchanger (NCX). Western blot analysis was performed to detect the expression of CaMKII, RyR2, SERCA, and NCX proteins in myocardial tissue from each group. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum levels of inflammatory factors interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). ResultsPathological staining results showed that compared with the blank control group, the model group exhibited disrupted atrial tissue structure, inflammatory cell infiltration, atrial fibrosis, and diffuse infiltration of numerous brown α-SMA positive cells in the atrial interstitium (P<0.01). AF could be induced by electrical stimulation with a longer duration. AERP was shortened, while APD dispersion, conduction heterogeneity index, and CaT dispersion were increased (P<0.01). The expression of proteins associated with diastolic calcium leakage, including CaMKⅡ, RyR2, and NCX1, showed elevated mRNA and protein levels, whereas SERCA2a mRNA and protein expression decreased (P<0.05). Serum levels of inflammatory factors IL-1β and TNF-α were elevated (P<0.01). Compared with the model group, intervention with WNG alleviated cardiac structural damage, reduced inflammatory cell infiltration, improved atrial fibrosis, and reduced the diffuse infiltration of α-SMA positive cells (P<0.01). AF inducibility and AF duration upon electrical stimulation were significantly reduced (P<0.05), AERP was prolonged (P<0.05), mRNA and protein expression of CaMKⅡ, RyR2, and NCX1-proteins associated with diastolic calcium leakage-were reduced, whilst mRNA and protein expression of SERCA2a increased (P<0.05), and serum levels of IL-1β and TNF-α were decreased (P<0.01). ConclusionBoth low‑ and high‑dose WNG can effectively reduce susceptibility to inflammation-related AF. The mechanism by which WNG reduce AF susceptibility may be related to regulating proteins involved in sarcoplasmic reticulum diastolic calcium leak, thereby improving cardiac electrical remodeling, and alleviating inflammation-induced myocardial fibrosis, thus improving cardiac structural remodeling.
4.Baicalein mitigates ferroptosis of neurons after subarachnoid hemorrhage
Ting ZHU ; Tingting YUE ; Yue CUI ; Yue LU ; Wei LI ; Chunhua HANG
Chinese Journal of Tissue Engineering Research 2025;29(1):52-57
BACKGROUND:Ferroptosis is a mode of programmed cell death distinct from apoptosis,necrosis,and other novel cellular deaths,which occurs mainly due to accumulated lipid peroxidation.Ferroptosis has been shown to be involved in the pathological process following subarachnoid hemorrhage.Baicalein,serving as an adept sequestered of iron,evinces its prowess by quelling lipid peroxidative cascades.Nonetheless,the enigma lingers as to whether baicalein possesses the capacity to ameliorate neuronal ferroptosis,elicited in the wake of early brain injury after subarachnoid hemorrhage. OBJECTIVE:To investigate the effect and mechanism of baicalein on neuronal ferroptosis after subarachnoid hemorrhage. METHODS:Primary neuronal cells were extracted from C57BL/6L fetal mice at 16-17 days of gestation.Hemoglobin was used to stimulate primary neuronal cells to simulate an in vitro subarachnoid hemorrhage model.The viability of primary neuronal cells treated with baicalein at concentrations of 5,15,25,50,and 100 μmol/L for 24 hours was detected by CCK-8 assay to determine the optimal concentration of baicalein.Primary neuronal cells were divided into control group,hemoglobin group,and hemoglobin+baicalein group.The levels of reactive oxygen species and malondialdehyde in cells were detected by kits.The mRNA expressions of ferroptosis-related markers PTGS2,SLC7A11,and glutathione peroxidase 4 were detected by RT-PCR.The primary neuronal cells were further divided into control group,SLC7A11 inhibitor Erastin group,hemoglobin group,hemoglobin+baicalein group,and hemoglobin+baicalein+Erastin group.The expression of the ferroptosis related markers SLC7A11 and glutathione peroxidase 4 was detected by western blot assay. RESULTS AND CONCLUSION:(1)Baicalein(25 μmol/L)was selected as the following experimental concentration.(2)Compared with the hemoglobin group,the level of malondialdehyde and the level of reactive oxygen species were significantly decreased(P<0.05)in the hemoglobin+baicalein group.(3)Compared with the hemoglobin group,the mRNA expression of PTGS2 significantly decreased,and the mRNA expression of SLC7A11 and glutathione peroxidase 4 significantly increased(P<0.000 1)in the hemoglobin+baicalein group.(4)SLC7A11 inhibitor Erastin could reverse the baicalin-improved ferroptosis effect to a certain extent(P<0.05).(5)The results showed that baicalein could alleviate the ferroptosis of neuronal cells after subarachnoid hemorrhage through the SLC7A11/GPX4 pathway.
5.Mechanism of Qishen Yiqi Dropping Pills in regulating gut microbiota and ROS/TXNIP/NLRP3 signaling pathway to improve chronic heart failure in rats
Lifei LYU ; Tingting ZHU ; Fan DING ; Yingdong LU ; Xiangning CUI
Journal of Beijing University of Traditional Chinese Medicine 2025;48(3):354-369
Objective:
This study explored the regulatory effects of QiShen Yiqi Dropping Pills (QSYQ) on chronic heart failure (CHF) in rats and their related mechanisms based on the gut microbiota and reactive oxygen species (ROS)/thioredoxin interacting protein (TXNIP)/NOD-like receptor protein 3 (NLRP3) signaling pathway.
Methods:
Sixty-five SPF-grade male SD rats were used to establish a CHF model through subcutaneous multiple injections of isoproterenol (ISO) combined with exhaustion and food control methods. The modeled rats were randomly divided into model, captopril (5.30 mg/kg), and QSYQ low-, medium-, and high-dose groups (0.08, 0.16, and 0.32 g/kg, respectively), with 11 rats per group, plus a blank group of seven rats. The medication groups were given corresponding drugs by gavage, whereas the blank and model groups were administered an equivalent volume of purified water continuously for four weeks. Rat heart function was assessed via transthoracic echocardiography, and myocardial tissue pathology changes were observed through hematoxylin and eosin staining. Serum levels of brain natriuretic peptide (BNP), lipopolysaccharide (LPS), interleukin-18 (IL-18), and interleukin-1β (IL-1β) were measured using an enzyme-linked immunosorbent assay. Automated biochemical analyzers were used to determine creatine kinase (CK), lactate dehydrogenase (LDH), and MB isoenzyme of creatine kinase (CK-MB) content. Myocardial ROS levels were examined using flow cytometry; myocardial TXNIP and NLRP3 expression were detected using immunohistochemistry. Real-time qPCR and Western blotting were used to examine myocardial mRNA and protein expression of TXNIP, NLRP3, apoptosis-related spot-like protein (ASC), caspase-1, and IL-1β, as well as myocardial thioredoxin (Trx) and colonic tight junction proteins (zonula occludens-1, ZO-1), occludin, and claudin-5. Differences in the gut microbiota of the blank, model, and QSYQ high-dose groups were determined using high-throughput 16S rDNA sequencing.
Results:
Compared to the blank group, the model group exhibited significantly reduced left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) (P<0.01); increased serum BNP, LPS, IL-18, and IL-1β (P<0.01) levels; increased CK, LDH, and CK-MB (P<0.01) contents; visible myocardial tissue fibrous edema, wavy appearance, cytoplasmic loosening, round vacuolar degeneration, local tissue fibrous dissolution replaced by proliferative connective tissue, accompanied by inflammatory cell infiltration; significantly increased myocardial ROS levels (P<0.01); and significantly increased myocardial TXNIP and NLRP3 expression (P<0.01). TXNIP, NLRP3, ASC, caspase-1, and IL-1β mRNA and protein expression were significantly increased (P<0.05, P<0.01, respectively), whereas Trx, ZO-1, occludin, and claudin-5 expression was significantly decreased (P<0.01). Compared to the model group, the QSYQ high-dose group showed the most significant changes (P<0.05, P<0.01), with significant increases in LVEF and LVFS (P<0.01); significant decreases in serum BNP, LPS, IL-18, and IL-1β levels (P<0.01); significant reductions in CK, LDH, and CK-MB content (P<0.01); improved myocardial tissue damage; significantly decreased myocardial ROS levels (P<0.01); and significantly reduced myocardial TXNIP and NLRP3 expression (P<0.01). TXNIP, NLRP3, ASC, caspase-1, and IL-1β mRNA and protein expression were significantly decreased (P<0.05, P<0.01), whereas Trx, ZO-1, occludin, and claudin-5 expression was significantly increased (P<0.01). 16S rDNA sequencing results confirmed that the gut microbiota of rats changed after modeling and drug intervention, with significant differences in both α- and β-diversity. Compared to the blank group, at the family level, the abundance of Oscillospiraceae decreased (P<0.05), whereas the abundance of Lactobacillaceae increased. At the species level, the abundance of Segatella copri and Treponema succinifaciens increased, whereas the abundance of Kineothrix alysoides (P<0.05), Ruminococcus callidus, and Prevotellamassilia timonensis decreased. Compared to the model group, at the family level, the abundance of Oscillospiraceae increased (P<0.05) in the QSYQ high-dose group, whereas the abundance of Lactobacillaceae decreased. At the species level, the abundance of Segatella copri and Treponema succinifaciens decreased, whereas the abundance of Kineothrix alysoides increased (P<0.05).
Conclusion
QSYQ can regulate the relative abundance of symbiotic bacteria Kineothrix alysoides in the intestines, reduce serum LPS levels, inhibit the ROS/TXNIP/NLRP3 signaling pathway, and improve inflammatory responses, thereby exerting therapeutic effects on CHF.
6.Overview of Preparation Characteristics and Application of the Mofeng Ointment Formulation (摩风膏方) in the Dunhuang Manuscript Unnamed Treatise on the Pulse (《亡名氏脉经》)
Tingting DOU ; Yuting WEI ; Cui MA ; Xingke YAN
Journal of Traditional Chinese Medicine 2025;66(12):1300-1304
The Mofeng Ointment Formulation (MOF, 摩风膏方) is recorded in the Dunhuang manuscript Unnamed Treatise on the Pulse (《亡名氏脉经》) and stands as a representative ancient external therapeutic formula in traditional Chinese medicine (TCM). Known for dispelling wind, activating blood circulation, warming the meridians, and relieving pain, it is particularly effective in treating rheumatic arthralgia. Through literature research, this paper systematically reviews the composition, preparation techniques, and clinical application characteristics of MOF. In recent years, advancements in modern pharmaceutical technology have led to the development of various innovative ointment-based formulations derived from the traditional recipe, such as Dunhuang Xiaoding Ointment (敦煌消定膏), Dunhuang Xiaozhong and Zhentong Ointment (Patch) (敦煌消肿镇痛膏/贴), Xiaoding Ointment (消定膏) gel patch, and Xiaoding Ointment (消定膏) cataplasm. These innovations explore pathways for transforming classical prescriptions into modern applications, providing a theoretical basis for the external TCM treatment of pain-related and orthopedic conditions.
7.SHI Zaixiang's Clinical Experience in Using Chaihu Guizhi Ganjiang Decoction (柴胡桂枝干姜汤) to Treat High Fever in Sepsis
Tingting ZHU ; Yingying LIU ; Hailan CUI ; Zhiying REN ; Mingjing SHAO ; Yan BIAN ; Liyan WANG ; Zhenjie CHEN ; Yuan LIU ;
Journal of Traditional Chinese Medicine 2025;66(16):1645-1648
This paper summarizes Professor SHI Zaixiang's clinical experience in treating high fever caused by sepsis using Chaihu Guizhi Ganjiang Decoction (柴胡桂枝干姜汤). He holds that the key pathogenesis of sepsis involves constrained heat in the shaoyang and internal accumulation of water and fluids. The clinical manifestations such as high fever, chills, and alternating sensations of cold and heat are attributed to pathogenic heat constrained in the shaoyang. Meanwhile, soft tissue edema and serous cavity effusions are due to shaoyang dysfunction and internal water retention. In clinical practice, treating sepsis-related high fever requires addressing both the shaoyang-constrained heat and the associated edema and effusions. The therapeutic approach focuses on harmonizing the shaoyang and resolving internal fluids, using Chaihu Guizhi Ganjiang Decoction as the base formula with flexible modifications. Professor SHI emphasizes that this formula shows a rapid antipyretic effect, particularly in cases where multiple anti-infective treatments have failed.
8.Predictive value of preoperative combined detection of NLR and PTAR for early abdominal infection after liver transplantation
Huabin PENG ; Ying LIU ; Fei HOU ; Shuang ZHAO ; Yizhi ZHANG ; Tingting CUI ; Zhiying HE ; Jingyi LIU ; Haofeng XIONG ; Liying SUN
Organ Transplantation 2025;16(6):931-943
Objective To investigate the predictive value of preoperative combined detection of neutrophil-to-lymphocyte ratio (NLR) and prothrombin time-international normalized ratio to albumin ratio (PTAR) for early abdominal infection after liver transplantation. Methods Clinical data of 287 recipients who underwent liver transplantation at the Liver Transplant Center of Beijing Friendship Hospital, Affiliated to Capital Medical University, from January 2020 to April 2024 were retrospectively analyzed. The patients were divided into infection group (n=60) and non-infection group (n=227) based on whether abdominal infection occurred within 30 days after surgery. The distribution characteristics of pathogens and infection time in infected patients were analyzed. Spearman correlation analysis was used to assess the correlation between NLR, PTAR, Child-Pugh score and preoperative model for end-stage liver disease (MELD) score. Univariate and multivariate logistic regression analyses were performed to identify risk factors for abdominal infection. Receiver operating characteristic (ROC) curves were plotted for NLR, PTAR, and the combined prediction model to evaluate their predictive efficacy for abdominal infection after liver transplantation. Based on the cutoff value of the combined model, recipients were divided into low-risk and high-risk groups, and Kaplan-Meier analysis was used to compare the cumulative incidence of abdominal infection within 30 days after surgery between the two groups. Results Among the 287 recipients who underwent liver transplantation, 60 developed bacterial or fungal abdominal infections postoperatively. A total of 86 strains were isolated from infected patients, with Gram-negative bacteria accounting for 58%, Gram-positive bacteria for 36%, and fungi for 5%. Preoperative NLR and PTAR were positively correlated with Child-Pugh and MELD scores (all 1 > r > 0, P < 0.05). Logistic regression analysis showed that preoperative NLR, preoperative PTAR, postoperative ICU stay duration and postoperative biliary leakage were risk factors for abdominal infection within 30 days after surgery. The area under the curve (AUC) for NLR, PTAR, Child-Pugh score and MELD score were 0.771, 0.735, 0.650 and 0.741, respectively. The AUC for the combined NLR and PTAR prediction model was 0.824 (95% confidence interval: 0.763-0.885, P < 0.001), with a cutoff value of 0.168. Kaplan-Meier analysis showed that the cumulative incidence of abdominal infection within 30 days after surgery was lower in the low-risk group than in the high-risk group, with statistically significant difference (P < 0.001). Conclusions Preoperative NLR and PTAR are independent risk factors for abdominal infection within 30 days after liver transplantation. The combined prediction model of NLR and PTAR may effectively identify high-risk recipients for early abdominal infection after liver transplantation, providing basis for early intervention.
9.Efficacy and safety of secukinumab in Chinese patients with psoriasis: Update of six-year real-world data and a meta-analysis.
He HUANG ; Yaohua ZHANG ; Caihong ZHU ; Zhengwei ZHU ; Yujun SHENG ; Min LI ; Huayang TANG ; Jinping GAO ; Dawei DUAN ; Hequn HUANG ; Weiran LI ; Tingting ZHU ; Yantao DING ; Wenjun WANG ; Yang LI ; Xianfa TANG ; Liangdan SUN ; Yanhua LIANG ; Xuejun ZHANG ; Yong CUI ; Bo ZHANG
Chinese Medical Journal 2025;138(23):3198-3200
10.Shewanella biofilm formation regulated by acyl-homoserine lactones and its application in UO22+ electrosorption.
Tingting LIU ; Hong SHU ; Qian LI ; Zhao CUI ; Guangyue LI ; Ting LI ; Yongdong WANG ; Jing SUN
Chinese Journal of Biotechnology 2025;41(8):3081-3097
Shewanella oneidensis MR-1, a Gram-negative bacterium with a significant role in the adsorption and reduction of uranium in wastewater and a quorum-sensing effect, can be used to remove uranium from wastewater. Exogenous signaling molecules (acyl-homoserine lactones, AHLs) can be added to induce the quorum sensing behavior for rapid biofilm formation, thereby improving the removal efficiency of this bacterium for uranium. Extracellular polymeric substances (EPS), as the significant components of biofilm, play a key role in biofilm formation. To investigate the quorum sensing behavior induced by AHLs, we systematically investigated the effects of AHLs on the EPS secretion and biofilm properties of S. oneidensis MR-1 by regulating parameters such as AHL species, concentration, addition time point, and contact time. The results showed that the addition of 10 μmol/L N-butyryl-l-homoserine lactone (C4-HSL) after 6 h of culture and continued incubation to reach the time point of 72 h significantly promoted the secretion of EPSs, in which the content of extracellular proteins and extracellular polysaccharides was increased by 15.2% and 28.2%, respectively, compared with that of the control group. The biofilm electrodes induced by signaling molecules showed superior properties, which were evidenced by an increase of exceeding 20 μm in biofilm thickness, an increase of 33.9% in the proportion of living cells, enhanced electroactivity, and an increase of 10.7% in the uranium removal rate. The biofilm electrode was confirmed to immobilize uranium in wastewater mainly by electrosorption, physicochemical adsorption, and electro-reduction through characterization means such as X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). This study provides a new technical idea for the efficient recovery of uranium in wastewater and enriches the theoretical system of quorum sensing regulation of electroactive biofilms.
Biofilms/drug effects*
;
Acyl-Butyrolactones/pharmacology*
;
Quorum Sensing/drug effects*
;
Uranium/metabolism*
;
Shewanella/metabolism*
;
Adsorption
;
Uranium Compounds/metabolism*
;
Wastewater/chemistry*
;
Biodegradation, Environmental
;
Extracellular Polymeric Substance Matrix/metabolism*


Result Analysis
Print
Save
E-mail