Berberine inhibits intracellular Ca2+ signals in mouse pancreatic acinar cells through M3 muscarinic receptors: Novel target, mechanism, and implication.

Berberine, a natural isoquinoline alkaloid, exhibits a variety of pharmacological effects, but the pharmacological targets and mechanisms remain elusive. Here, we report a novel finding that berberine inhibits acetylcholine (ACh)-induced intracellular Ca2+ oscillations, mediated through an inhibition of the muscarinic subtype 3 (M3) receptor. Patch-clamp recordings and confocal Ca2+ imaging were applied to acute dissociated pancreatic acinar cells prepared from CD1 mice to examine the effects of berberine on ACh-induced Ca2+ oscillations. Whole-cell patch-clamp recordings showed that berberine (from 0.1 to 10 µM) reduced ACh-induced Ca2+ oscillations in a concentration-dependent manner, and this inhibition also depended on ACh concentrations. The inhibitory effect of berberine neither occurred in intracellular targets nor extracellular cholecystokinin (CCK) receptors, chloride (Cl-) channels, and store-operated Ca2+ channels. Together, the results demonstrate that berberine directly inhibits the muscarinic M3 receptors, further confirmed by evidence of the interaction between berberine and M3 receptors in pancreatic acinar cells.

Cloning and characterization of an aerolysin gene from a marine pathogen Vibrio splendidus.

Vibrio splendidus is one of the main pathogens caused diseases with a diversity of marine cultured animals, especially the skin ulcer syndrome in Apostichopus japonicus. However, limited virulence factors have been identified in V. splendidus. In this study, one aerAVs gene coding an aerolysin of V. splendidus was cloned and conditionally expressed in Escherichia coli. The haemolytic activity of the recombinant AerAVs was analyzed. Western blotting was used to study of the secretion pathway of proaerolysin, and it showed that the proaerolysin was secreted via both outer membrane vehicles and classical secretion pathways. Since no active protein of aerolysin was obtained, one aerolysin surface displayed bacterium DH5α/pAT-aerA was constructed, and its haemolytic activity and virulence were determined. The results showed that the AerAVs displayed on the surface showed obvious haemolytic activity and cytotoxic to the coelomocyte of A. japonicus. Artificial immerse infection separately using the DH5α/pAT or DH5α/pAT-aerA was conducted. The result showed that the mortality percent of sea cucumber A. japonicus challenged with DH5α/pAT-aerA was 38.89 % higher than that challenged with the control strain DH5α/pAT, and earlier death occurred. Combined all the results indicates that aerolysin with the haemolytic activity and cytotoxic activity is a virulence factor of V. splendidus.

[Effects of Straw Returning with Lime on SOC and Carbon Pool Management in Acidic Paddy Soil].

Soil acidification and low SOC are the main limiting factors in acidic paddy soils. Straw returning with lime is an effective measure to alleviate soil acidification and improve soil fertility; however, its interaction effects on SOC and carbon pool management are still unclear. To investigate the impact of straw returning with lime on the organic carbon pool of acidic paddy soil, field experiments were conducted on acidic paddy soil in Baiyun District and Huiyang District of Guangdong Province. The changes in soil total organic carbon (TOC), water-soluble organic carbon (DOC), active organic carbon (LOC), particulate organic carbon (POC), microbial biomass carbon (MBC), carbon pool index (CPI), stable organic carbon (IOC), carbon pool activity (L), carbon pool activity index (CPAI), and carbon pool management index (CPMI) were analyzed under three treatments (CK, conventional fertilization; RS, straw returning+conventional fertilization; RS+L straw returning with lime+conventional fertilization). The results demonstrated that compared with that in CK, the TOC, LOC, POC, and MBC in the RS+L treatment were significantly increased by 10.24%-17.79%, 34.49%-44.37%, 19.27%-23.59%, and 33.36%-43.26%, respectively (P<0.05). Compared with that in CK, the RS+L treatment significantly increased the DOC content during the early growth stage (15-45 days after transplanting) of rice (P<0.05) but had no significant influence on the DOC content during the late growth stage of rice. Compared with that in RS, the TOC, LOC, POC, and MBC in the RS+L treatment were increased by 2.15%-6.95%, 1.17%-17.90%, 4.27%-8.65%, and 12.99%-14.53%, respectively. Compared with that in CK, the RS+L treatment significantly increased IOC and CPI by 8.32%-15.57% and 14.00%-20.00%, respectively (P<0.05). Compared with that in the CK treatment, the RS treatment significantly increased CPI by 14.00%-18.00% (P<0.05). No significant differences in L, CPAI, or CPMI were detected among the different treatments. The soil pH in the RS+L treatment was significantly higher than that in the CK treatment (P<0.05). No significant differences in rice yield were detected among the different treatments. Principal component analysis demonstrated that rice yield was primarily correlated with DOC, LOC, CPAI, and CPMI but its contribution to SOC and carbon pool management index was low. Principal component analysis also indicated that straw returning with lime could improve soil pH and nutrient contents of acidic paddy soil, driving the formation and accumulation of organic carbon fraction such as MBC and POC, thus boosting the increase in SOC. In conclusion, straw returning with lime is beneficial to the accumulation of MBC, POC, LOC, and IOC in acidic paddy soil to improve the content and stability of soil total organic carbon, which is an effective way to improve the carbon sequestration of acidic paddy soil.

METTL14-upregulated miR-6858 triggers cell apoptosis in keratinocytes of oral lichen planus through decreasing GSDMC.

Oral lichen planus (OLP), a chronic inflammatory disorder, is characterized by the massive cell apoptosis in the keratinocytes of oral mucosa. However, the mechanism responsible for triggering oral keratinocyte apoptosis is not fully explained. Here, we identify that Gasdermin C (GSDMC) downregulation contributes to apoptosis in human oral keratinocytes. Mechanistically, we describe that activated nuclear factor kappa B (NF-κB) pathway induces overexpression of methyltransferase-like 14 (METTL14), which increases N6-adenosine methylation (m6A) levels in the epithelial layer of OLP. m6A modification is capable of regulating primary miR-6858 processing and alternative splicing, leading to miR-6858 increases. miR-6858 can bind and promote GSDMC mRNA degradation. Forced expression of GSDMC is able to rescue cell apoptosis in human oral keratinocyte models resembling OLP. Collectively, our data unveil that m6A modification regulates miR-6858 production to decrease GSDMC expression and to trigger keratinocyte apoptosis in the context of OLP.

A solution-to-solid conversion chemistry enables ultrafast-charging and long-lived molten salt aluminium batteries.

Conventional solid-to-solid conversion-type cathodes in batteries suffer from poor diffusion/reaction kinetics, large volume changes and aggressive structural degradation, particularly for rechargeable aluminium batteries (RABs). Here we report a class of high-capacity redox couples featuring a solution-to-solid conversion chemistry with well-manipulated solubility as cathodes-uniquely allowed by using molten salt electrolytes-that enable fast-charging and long-lived RABs. As a proof-of-concept, we demonstrate a highly reversible redox couple-the highly soluble InCl and the sparingly soluble InCl3-that exhibits a high capacity of about 327 mAh g-1 with negligible cell overpotential of only 35 mV at 1 C rate and 150 °C. The cells show almost no capacity fade over 500 cycles at a 20 C charging rate and can sustain 100 mAh g-1 at 50 C. The fast oxidation kinetics of the solution phase upon initiating the charge enables the cell with ultrafast charging capability, whereas the structure self-healing via re-forming the solution phase at the end of discharge endows the long-term cycling stability. This solution-to-solid mechanism will unlock more multivalent battery cathodes that are attractive in cost but plagued by poor reaction kinetics and short cycle life.

Sr14.06Gd14.63(BO3)24: A Gadolinium-Rich Borate with Magnetic Refrigeration Performance.

A single crystal of Sr14.06Gd14.63(BO3)24 has been successfully grown through a high-temperature solution technique with K2O-KF-B2O3 as the flux. It crystallizes in the Pnma space group with parameters a = 22.3153(5) Å, b = 15.9087(4) Å, c = 8.7507(2) Å, and Z = 2. Sr14.06Gd14.63(BO3)24 has a three-dimensional (3D) framework built from [GdO] chains, in which the isolate [BO3]3- groups and Sr2+ ions fill in the space of the 3D framework. The magnetic measurements revealed that the title compound exhibits a large magnetocaloric effect with the magnetic entropy change of -ΔSm = 42.2 J kg-1 K-1 at 2 K for 7 T, which is higher than that of the commercial material, Gd3Ga5O12 (GGG), with -ΔSm of 38.4 J kg-1 K-1 under the same conditions. Moreover, the infrared spectrum (IR), UV-vis-NIR diffuse reflectance spectrum, and thermal stability were investigated.

Proteomic analysis reveals the adaptation of Vibrio splendidus to an iron deprivation condition.

Vibrio splendidus is a ubiquitous Gram-negative marine bacterium that causes diseases within a wide range of marine cultured animals. Since iron deprivation is the frequent situation that the bacteria usually encounter, we aimed to explore the effect of iron deprivation on the proteomic profile of V. splendidus in the present study. There were 425 differentially expressed proteins (DEPs) responded to the iron deprivation condition. When the cells were grown under iron deprivation condition, the oxidation‒reduction processes, single-organism metabolic processes, the catalytic activity, and binding activity were downregulated, while the transport process, membrane cell component, and ion binding activity were upregulated, apart from the iron uptake processes. Kyoto Encyclopedia of Genes and Genomes analysis showed that various metabolism pathways, biosynthesis pathways, energy generation pathways of tricarboxylic acid cycle, and oxidative phosphorylation were downregulated, while various degradation pathways and several special metabolism pathways were upregulated. The proteomic profiles of cells at a OD600 ≈ 0.4 grown under iron deprivation condition showed high similarity to that of the cells at a OD600 ≈ 0.8 grown without iron chelator 2,2'-bipyridine. Correspondingly, the protease activity, the activity of autoinducer 2 (AI-2), and indole content separately catalyzed by LuxS and TnaA, were measured to verify the proteomic data. Our present study gives basic information on the global protein profiles of V. splendidus grown under iron deprivation condition and suggests that the iron deprivation condition cause the cell growth enter a state of higher cell density earlier. KEY POINTS: • Adaptation of V. splendidus to iron deprivation was explored by proteomic analysis. • GO and KEGG of DEPs under different iron levels or cell densities were determined. • Iron deprivation caused the cell enter a state of higher cell density earlier.

ß-Blockers could improve the 28-day and 3-year survival of patients with end-stage renal disease: a retrospective cohort study.

BACKGROUND: Dialysis or non-dialysis end-stage renal disease (ESRD) patients are accompanied by cardiovascular disease (CVD) or hypertension. We aimed to study the effect of a common treatment for CVD, ß-blockers, on the survival of ESRD patients, improving their prognosis from the perspective of drug therapy. METHODS: It was a retrospective cohort study using the Medical Information Mart for Intensive Care dataset. ESRD patients in the intensive care unit from June 2001 to October 2012 were included. We examined the effect of using versus not using ß-blockers in the overall population and subgroups with the risk of 28-day and 3-year mortality through Cox proportional hazards models and Kaplan-Meier curves. RESULTS: A total of 1639 participants were included with 371 (22.64%) ß-blockers users. There were 315 (19.22%) 28-day and 970 (59.18%) 3-year mortality events during follow-up. Using ß-blockers in overall ESRD patients could reduce all-cause 28-day mortality [adjusted hazard ratio (HR) 0.450, 95% confidence interval (CI) 0.325-0.624] and 3-year mortality (adjusted HR 0.695, 95% CI 0.589-0.821). This result was consistent among subgroups (ESRD without hypertension: adjusted HR 0.412, 95% CI 0.289-0.588; with CVD: adjusted HR 0.478, 95% CI 0.321-0.711; without CVD: adjusted HR 0.448, 95% CI 0.248-0.810; with dialysis: adjusted HR 0.471, 95% CI 0.320-0.694) in 28-day mortality, and the 3-year mortality was consistent. In ESRD patients with hypertension and without dialysis subgroups, ß-blockers had no effect on survival. CONCLUSION: Using ß-blockers could reduce the risk of 28-day and 3-year mortality in ESRD patients, including those with CVD. This study provided a reference for the treatment of ß-blockers in patients with ESRD.

Quality degradation of alfalfa caused by CO2 leakage from carbon capture and storage.

A complete understanding of the potential environmental risks associated with carbon capture and storage (CCS) is critical for its large-scale deployment. Many experiments have simulated plant responses to soil CO2 stress caused by CCS leakage; however, crop quality has received less attention. This study assessed the effects of leaked CO2 from CCS on alfalfa yield and nutritional quality using pot experiments, focusing on crude protein and amino acids to address this knowledge gap. Our results showed that the aboveground and underground fresh weights decreased by 43.55 % and 66.06 %, respectively. The root-to-shoot ratio of alfalfa decreased from 1.04 to 0.63, indicating greater inhibition effects on the root than on the aboveground part of alfalfa. Crude protein and total amino acids in alfalfa declined by approximately 15.20 % and 11.37 %, respectively, compared to the non-leaked scenario. Our findings could potentially shed light on the environmental impact of CCS leakage, explicitly concerning the decline of crop quality, which adds to existing knowledge of the environmental effects of CCS failure.

Modeling Community Residents' Exercise Adherence and Life Satisfaction: An Application of the Influence of the Reference Group.

To expand the application area of the reference group and enrich exercise theoretical research, based on Stimulus-Organism-Response (SOR) framework, this study examines the external factors that motivate adherence to exercise. Taking reference group and strategy and cultural fit as the main stimuli, and personal investment and life satisfaction as mediating variables, this study explores the influence of external stimuli on residents' exercise behavior. In order to enrich the sample size, two surveys of 734 Chinese residents in two cities (Xiamen vs. Fuzhou) were conducted using factor analyses, regression analysis, and t-test analysis. The results indicated that the reference group and strategic and cultural fit as external stimuli impact on residents' personal investment, life satisfaction and exercise adherence, and that personal investment and life satisfaction as the organism has an impact on residents' exercise adherence. Personal investment and life satisfaction play a chain mediating role between the reference group and exercise adherence, and between strategy and cultural fit and exercise adherence. Moreover, the t-test determined the differences between Xiamen and Fuzhou residents' exercise adherence and life satisfaction. Residents' surroundings affect their exercise behavior and life satisfaction. These findings have implications for policymaking aimed at promoting national exercise, which could gradually improve residents' physical fitness, particularly in light of the current coronavirus emergency.

Porous Nitrogen-Defected Carbon Nitride Derived from A Precursor Pretreatment Strategy for Efficient Photocatalytic Degradation and Hydrogen Evolution.

Graphitic carbon nitride (g-C3N4) has attracted extensive research attention because of its virtues of a metal-free nature, feasible synthesis, and excellent properties. However, the low specific surface area and mediocre charge separation dramatically limit the practical applications of g-C3N4. Herein, porous nitrogen defective g-C3N4 (PDCN) was successfully fabricated by the integration of urea-assisted supramolecular assembly with the polymerization process. Advanced characterization results suggested that PDCN exhibited a much larger specific surface area and dramatically improved charge separation compared to bulk g-C3N4, leading to the formation of more active sites and the improvement in mass transfer. The synthesized PDCN rendered a 16-fold increase in photocatalytic tetracycline degradation efficiency compared to g-C3N4. Additionally, the hydrogen evolution rate of PDCN was 10.2 times higher than that of g-C3N4. Meanwhile, the quenching experiments and electron spin resonance (ESR) spectra suggested that the superoxide radicals and holes are the predominant reactive species for the photocatalytic degradation process. This study may inspire the new construction design of efficient g-C3N4-based visible-light photocatalysts.

Synergy of intermolecular Donor-Acceptor and ultrathin structures in crystalline carbon nitride for efficient photocatalytic hydrogen evolution.

Crystalline carbon nitride is regarded as the new generation of emerging metal-free photocatalysts as opposed to polymeric carbon nitride (g-C3N4) because of its high crystalline structure and ultrahigh photocatalytic water splitting performance. However, further advances in crystalline g-C3N4 are significantly restricted by the sluggish separation of charge carriers and limited active sites. In this study, we demonstrate the successful synthesis of heptazine-triazine donor-acceptor-based ultrathin crystalline g-C3N4 nanosheets (UCCN) using a combined hot air exfoliation and molten salt (NaCl/KCl) copolymerization approach. The synergy of the donor-acceptor heterojunction and the ultrathin structure greatly accelerated the separation of the charge carriers and enriched the active sites. Accordingly, the superior hydrogen evolution activity and an ultrahigh apparent quantum efficiency of 73.6% at 420 nm under a natural photosynthetic environment were achieved by UCCN, positioning this material at the top among reported conjugated g-C3N4 materials. This study provides a novel paradigm for the development of donor-acceptor-based ultrathin crystalline layered materials.

Pressure-Driven Two-Step Second-Harmonic-Generation Switching in BiOIO3.

Materials with multi-stabilities controllable by external stimuli have potential for high-capacity information storage and switch devices. Herein, we report the observation of pressure-driven two-step second-harmonic-generation (SHG) switching in polar BiOIO3 for the first time. Structure analyses reveal two pressure-induced phase transitions in BiOIO3 from the ambient noncentrosymmetric phase (SHG-high) to an intermediate noncentrosymmetric phase (SHG-intermediate) and then to a centrosymmetric phase (SHG-off). The three-state SHG switching was inspected by in situ high-pressure powder SHG and polarization-dependent single-crystal SHG measurements. Local structure analyses based on the in situ Raman spectra and X-ray absorption spectra reveal that the SHG switching is caused by the step-wise suppression of lone-pair electrons on the [IO3 ]- units. The dramatic evolution of the functional units under compression also leads to subtle changes of the optical absorption edge of BiOIO3 . Materials with switchable multi-stabilities provide a state-of-art platform for next-generation switch and information storage devices.

Relationship between serum TGF- ß 1, MMP-9 and IL-1ß and pathological features and prognosis in breast cancer.

To investigate the levels of serum transforming growth factor-ß 1 (TGF-ß1), Matrix metalloproteinase-9 (MMP-9) and Interleukin-1 ß (IL-1 ß) in breast cancer (BC), and analyzing their relationship with pathological features and prognosis. Retrospective analysis of 86 subjects with BC (BC subgroup) and another 50 healthy subjects (control subgroup) during the same period were included. The clinical data were collected. In this research, in BC subgroup, The levels of serum TGF- ß 1, MMP-9 and IL-1 ß were significantly higher than those in control subgroup. The levels of TGF- ß 1 and MMP-9 in serum of BC subjects was correlated with clinical stage, histological grade, lymph node metastasis and molecular classification, but not with age, tumor size and menopausal status. The level of serum IL-1 ß was related to tumor size, clinical stage, histological grade and lymph node metastasis. Multivariate Logistic regression analysis showed that the high level of serum TGF- ß1 and MMP-9 was independent risk factors for BC. High level of serum IL-1 ß was not an independent risk factor for BC. The 3-year disease-free survival rate in high TGF- ß1 subgroup and high MMP-9 subgroup was significantly lower than that in low TGF- ß 1 subgroup and low MMP- 9 subgroup. To conclude, serum TGF- ß 1, MMP-9 and IL-1ß are highly expressed in BC, and the subjects with elevated serum levels of TGF- ß 1 and MMP-9 suggests poor prognosis.

Driving mechanism of drift-step-recovery diodes.

Parameters governing forward and reverse pumping of a device mechanism have an important influence on the cutoff and output characteristics of a drift-step-recovery diode (DSRD). Therefore, we analyzed the driving circuit for the DSRD that was used to adjust pumping parameter values. With multiple modules in parallel, a driving method exploiting narrow-pulse pumping is proposed in developing a high-repetition-frequency DSRD pulse generator. In experiments and simulations, one key factor affecting the working stability of this pulse generator operating at repetition frequencies in the megahertz range was found that helped in further optimizing the parameter settings of our 2 kV DSRD driving circuit. From this insight, a 2 kV-5 MHz all-solid-state high-repetition-frequency pulse generator based on the DSRD was developed.

RNF213 gene silencing upregulates transforming growth factor ß1 expression in bone marrow-derived mesenchymal stem cells and is involved in the onset of Moyamoya disease.

Moyamoya disease (MMD) is a chronic and progressive cerebrovascular occlusion disease, the precise etiology of which is poorly understood. Ring finger protein 213 (RNF213) has been previously identified as a susceptibility gene that serves an important role in angiogenesis, where it has been shown to be closely associated with the onset of MMD. Patients with MMD exhibit increased expression levels of various pro-inflammatory molecules and angiogenic factors. Under certain conditions, bone marrow mesenchymal stem cells (BMSCs) have the ability to differentiate to form neuron-like and microglia-like cells. In the present study, a total of 40 MMD patients and 40 healthy individuals were enrolled. ELISA assays revealed that the expression of serum vascular endothelial growth factor (VEGF) and transforming growth factor ß1 (TGF-ß1) were higher than that in healthy controls. Furthermore, rat BMSCs (rBMSCs) were isolated and cultured using the whole bone marrow adherence method, which were then phenotyped using flow cytometry. Osteogenic and adipogenic differentiation were determined by using Alizarin red and oil red O staining, respectively. RNF213 was knocked-down using a lentivirus-mediated short hairpin RNA system in passage three rBMSCs, and successful transfection of the RNF213 was confirmed by RT-qPCR and fluorescence imaging. The expression levels of VEGF and TGF-ß1 in these rBMSCs were measured on days 7 and 14, respectively. The results demonstrated that RNF213 knockdown upregulated TGF-ß1 at both protein and mRNA levels, but did not exert any effect on VEGF gene expression. In conclusion, these findings suggested that that RNF213 knockdown may contribute to aberrant TGF-ß1 expression via a pathway that remains to be unidentified, indicating that quantitative changes in RNF213 gene expression may serve an important role in the pathogenesis of MMD.

Large Magnetocaloric Effect in Li3K9Gd3(BO3)7 Crystal Featuring Sandwich-Like Three-Dimensional Framework.

A new Gd-based borate crystal, Li3K9Gd3(BO3)7, has been successfully obtained via the high-temperature solution method using Li2O-K2O-B2O3 self-flux. It crystallizes in monoclinic space group P2/n (no. 10) with lattice parameters a = 11.3454(6) Å, b = 9.9881(4) Å, c = 11.4467(7) Å, α = γ = 90 o, ß = 114.782(7) o, and Z = 2. Li3K9Gd3(BO3)7 exhibits an intriguing sandwich-like three-dimensional (3D) framework constructed from [Gd-B-O]∞ layers, KOn (n = 6 and 8) polyhedra, and LiO4 tetrahedra, in which [Gd-B-O]∞ layers are built from two types of GdO8 polyhedra and triangular BO3 units. Magnetic measurements showed that Li3K9Gd3(BO3)7 exhibits a large magnetocaloric effect with -ΔSm = 39.3 J kg-1 K-1 at 2.0 K for ΔH = 7 T, which is slightly higher than that of the commercial gadolinium gallium garnet under the same conditions. The powder X-ray diffraction, infrared spectrum, and UV-vis-NIR diffuse reflectance spectrum were also performed to characterize Li3K9Gd3(BO3)7. The electronic band structures, partial density of states, and refractive indices of Li3K9Gd3(BO3)7 were investigated via the first-principle calculations.

Na3Bi(IO3)6: An Alkali-Metal Bismuth Iodate with Intriguing One-Dimensional [BiI6O18] Chains and Pressure-Induced Structural Transition.

An alkali-metal bismuth iodate, Na3Bi(IO3)6, was successfully obtained by the hydrothermal method for the first time and contains intriguing one-dimensional [BiI6O18] chains. High-pressure Raman spectra were carried out to investigate the structural transition of Na3Bi(IO3)6. Electronic states and anisotropic optical responses were also investigated by theoretical calculations.

Europium(III) complex fluorescent sensor for dual channel recognition of Sn2+ and Cu2+ ions in water.

A new europium(III) complex Eu(tta)3L1 (1a) (L1 = (2-(3,5-dimethoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), tta = 2-thenoyltrifluoroacetone) has been prepared and synthesized. The structure of complex was completely determined by several different analytical techniques including single-crystal X-ray diffraction, 1H and 13C NMR. The crystal structure of the complex 1a belonged to monoclinic system with the space group P21/n. Its fluorescent properties were systematically studied in details by adding different metal ions in deionized water. Upon addition of Sn2+, its fluorescence intensity was strengthened and centered at 460 nm. And when Cu2+ was added, its fluorescence emission intensity was quenched quickly. The LODs for Sn2+ and Cu2+ were calculated to be 4.52 × 10-7 mol L-1 and 1.11 × 10-7 mol L-1, respectively. Furthermore, this sensor was successfully employed to monitor Sn2+ and Cu2+ in practical samples.

Prevalence of burnout among intensivists in mainland China: a nationwide cross-sectional survey.

BACKGROUND: Burnout has gained increasing attention worldwide; however, there is a lack of relevant research in China. This study investigated the prevalence and factors associated with burnout in physicians of the intensive care unit (ICU) in mainland China. METHODS: This cross-sectional multicenter study included critical care physicians from all provinces in mainland China (except Tibet). A self-administered survey questionnaire was conducted. It included three parts: demographic information, lifestyle and work information, and the Maslach Burnout Inventory. The levels of burnout were calculated. The factors independently associated with burnout were analyzed by logistic regression. RESULTS: Finally, 1813 intensivists participated in the survey. The participation rate was 90.7%. The prevalence of burnout and severe burnout was 82.1% (1489/1813) and 38.8% (704/1813), respectively. According to the logistic regression analysis, "difficulty in making treatment decisions" was independently associated with burnout [OR = 1.365, CI (1.060, 1.757)]. "Higher number of children" [OR = 0.714, CI (0.519, 0.981)] and higher "income satisfaction" [OR = 0.771, CI (0.619, 0.959)] were independent protective factors against severe burnout. CONCLUSIONS: The burnout rate in ICU physicians in China is high. Difficult treatment decisions, the number of children, and income satisfaction are independently associated with burnout rates among ICU physicians in China. TRIAL REGISTRATION: Burnout syndrome of the Chinese personnel working in intensive care units: a survey in China, ChiCTR-EOC-17013044, registered October 19, 2017. http://www.chictr.org.cn/showproj.aspx?proj=22329 .