A cellulose nanocrystal-based dual response of photonic colors and fluorescence for sensitive benzene gas detection.

Benzene, as a common volatile organic compound, represents serious risk to human health and environment even at low level concentration. There is an urgent concern on visualized, sensitive and real time detection of benzene gases. Herein, by doping Fe3+ and graphene quantum dots (GQDs), a cellulose nanocrystal (CNC) chiral nematic film was designed with dual response of photonic colors and fluorescence to benzene gas. The chiral nematic CNC/Fe/GQDs film could respond to benzene gas changes by reversible motion. Moreover, chiral nematic film also displays reversible responsive to humidity changes. The resulting CNC/Fe/GQDs chiral nematic film showed excellent response performance at benzene gas concentrations of 0-250 mg/m3. The maximal reflection wavelength film red shifted from 576 to 625 nm. Furthermore, structural color of CNC/Fe/GQDs chiral nematic film change at 44 %, 54 %, 76 %, 87 %, and 99 % relative humidity. Interestingly, due to the stability of GQDs to water molecules, CNC/Fe/GQDs chiral nematic film exhibit fluorescence response to benzene gas even in high humidity (RH = 99 %) environment. Besides, we further developed a smartphone-based response network system for quantitively determinization and signal transformation. This work provides a promising routine to realize a new benzene gas response regime and promotes the development of real-time benzene gas detection.

Allergic hyper-carcinoembryonic antigen syndrome: A syndrome summarized by case series.

Allergic respiratory diseases can increase serum carcinoembryonic antigen levels. We report three cases experiencing allergic symptoms that proved refractory to inhaled corticosteroids but exhibited a positive response to long-term treatment with oral corticosteroids. This response was characterized by a synchronous alteration in serum eosinophil counts and carcinoembryonic antigen levels. Immunofluorescence assays indicated localized carcinoembryonic antigen production within eosinophils. In addition, we conducted a systematic review of patients exhibiting similar characteristics on PubMed. After comprehensively reviewing this unique pathophysiological condition, we herein introduced a novel term "Allergic hyper-carcinoembryonic antigen syndrome," defined by the following criteria: (1) recurrent asthmatic attacks; (2) eosinophilia or pulmonary eosinophilic infiltrations accompanied by elevated serum carcinoembryonic antigen levels; (3) pulmonary lesions determined by imaging or biopsy; (4) exclusion of malignancy and infections; and (5) responsive to systemic corticosteroids. Allergic hyper-carcinoembryonic antigen syndrome suggests systemic corticosteroids should be introduced early when managing allergic patients with both eosinophilia and elevated serum carcinoembryonic antigen levels.

Theory-Guided Experimental Design of Covalent Triazine Frameworks for Efficient Photocatalytic Hydrogen Production.

The high crystalline covalent triazine framework-1 (CTF-1), composed of alternating triazine and phenylene, has emerged as an efficient photocatalyst for solar-driven hydrogen evolution reaction (HER). However, it is of great challenge to further improve photocatalytic HER performance via increasing crystallinity due to its near-perfect crystallization. Herein, an alternative strategy of scaffold functionalization is employed to optimize the energy band structure of crystalline CTF-1 for boosting hydrogen-evolving activity. Guided by the computational predictions, versatile CTF-based polymer photocatalysts are prepared with different functional groups (OH, NH2, COOH) using binary polymerization for practical hydrogen production. Experiment evidence verifies that the introduction of a limited number of electron-donating groups is sufficient to maintain high crystallinity in CTF, modulate the band structure, broaden visible light absorption, and consequently enhance its photophysical properties. Notably, the functionalization with OH exhibits the most positive effect on CTF-1, delivering a photocatalytic activity with a hydrogen-producing rate exceeding 100 µmol h-1.

Causal relationship between dietary salt intake and dementia risk: Mendelian randomization study.

OBJECTIVE: Observational research has indicated a potential link between dietary salt intake and susceptibility to dementia. However, it is important to note that these types of studies are prone to the issues of reverse causation and residual confounding. Therefore, we conducted a two-sample Mendelian randomization (MR) study to explore the causality. METHOD: To explore the causal relationship between them, this Mendelian randomization (MR) study incorporated summary statistics of dietary salt intake and dementia. We estimated the causality between salt intake and the risk of overall dementia and various subtypes of dementia, including Alzheimer's disease (AD), Vascular dementia (VaD), and Lewy body dementia (LBD). The inverse variance-weighted (IVW) method was the major MR analysis. To conduct sensitivity analyses, we employed various MR methods, the pleiotropy residual sum and outlier (MR-PRESSO) method, and the leave-one-out approach. The MR-Egger intercept and Cochran's Q test were conducted to test pleiotropy and heterogeneity respectively. RESULTS: A suggestive association was observed for genetically predicted higher dietary salt intake and increased risk of overall dementia in the European ancestry [odds ratio (OR): 1.542; 95% confidence interval (95% CI): 1.095-2.169; P = 0.013]. The causal relationship between dietary salt intake and overall dementia is robust with respect to the choice of statistical methods and is validated through extensive sensitivity analyses that guard against various model assumption violations. Meanwhile, no clear heterogeneity or pleiotropy was identified. However, we failed to detect a causal effect of dietary salt intake on the risk of various dementia subtypes. CONCLUSION: The results of this research present strong evidence that established a significant association between dietary salt intake and the likelihood of developing dementia. These findings reinforce the notion that the amount of dietary salt intake plays a crucial role in determining the risk of acquiring this cognitive condition. By establishing a definitive correlation, this study highlights the importance of reducing salt consumption as a preventive measure against dementia.

Constructing LiF-Dominated Interphases with Polymer Interwoven Outer Layer Enables Long-Term Cycling of Si Anodes.

Constructing a robust solid electrolyte interphase (SEI) is extremely critical to developing high-energy-density silicon (Si)-based lithium-ion batteries. However, it is still elusive how to accurately manipulate the chemical composition and structure of the SEI layer. Herein, a LiF-dominated SEI film intertwined by a highly elastic polymer is achieved by regulating the defluorination mechanism of the fluorinated carbonate additive on the Si electrode surface. The experimental and computational results confirm that the decomposition route of trans-difluoroethylene carbonate (DFEC) molecules can be significantly altered in the presence of lithium difluoro(oxalato)borate (LiDFOB) additive. The induction of direct defluorination of DFEC step by LiDFOB, as opposed to the breaking of C-O bonds without LiDFOB addition, is crucial in ensuring the exclusive formation of LiF-dominated SEI and maintaining the cyclic structure of DFEC. The defluorinated DFEC easily polymerizes to form poly(vinylene carbonate), enhancing the elasticity of the SEI. The resulting LiF-dominated SEI film with a polymer interwoven outer layer shows enhanced ionic conductivity and mechanical stability, which can effectively accelerate electrode reaction kinetics and maintain the structural stability of the Si electrode. As a result, the Si electrode with the electrolyte containing the designed dual-additive exhibits superior cycling stability and excellent rate performance, delivering a high reversible capacity of 1487.3 mAh g-1 after 1000 cycles at 2 A g-1.

Compact Fluorescence Spectrometer with Built-In In-Line Calibration: Application to Detect Dissolved Organic Matter in Water.

Fluorescence spectrometer (FS) is widely used for component analysis because each fluorescing material has its own characteristic spectrum. However, the spectral calibration is complicated and bulky. Herein, an in-line spectral calibration sheet (ISCS) was proposed in which a narrow band-pass filter and a linear variable filter (LVF) were integrated on a metal plate. By moving the ISCS, the transmitted excitation light power (TEP) as well as fluorescence spectrum can be seamlessly scanned, and the TEP can be used for in-line spectral calibration. A compact FS apparatus based on UV-LED excitation, metal capillary (MC) and ISCS was fabricated (i.e., ISCS-FS), and the ISCS-FS apparatus was applied to detect sodium humate in water. By employing TEP calibration, both the primary inner filter effect (PIFE) and the drift in the optical power of UV-LED can be simultaneously compensated. The linear correlation coefficient of signal concentration was improved from 0.89 to 0.998, and the relative standard deviation (RSD) of replicated detection was improved from 3 to 0.7%. A detection limit of concentration (DLC) of 1.3 µg/L was realized, which is 15-fold lower than that of a commercial FS apparatus (20 µg/L). The DLC is even comparable with that (0.5-4 µg/L) of commercial total organic carbon (TOC) analyzers, which are bulky and expensive. The linear correlation between the measurement results of ISCS-FS and commercial TOC analyzers can reach a good value of 0.94.

Successful treatment of severe Pneumocystis Jirovecii pneumonia in a diffuse large B-cell lymphoma patient after R-CHOP chemotherapy: A case report.

R-CHOP chemotherapy has been established as the first-line standard treatment for elderly patients diagnosed with diffuse large B-cell lymphoma. However, an increased risk of Pneumocystis jirovecii pneumonia in diffuse large B-cell lymphoma patients after the rituximab-based chemotherapy has been reported. We describe a case who developed intermittent cough, fever and shortness of breath after five cycles of R-CHOP treatment for diffuse large B-cell lymphoma. A rapid deterioration in patient's respiratory condition prompted us to adopt an aggressive anti- Pneumocystis jirovecii pneumonia strategy that combined the conventional trimethoprim/sulfamethoxazole and another two antimicrobials, caspofungin and clindamycin. This is the first report mentioning the successful treatment of severe Pneumocystis jirovecii pneumonia with a triple-drug regimen in a HIV-uninfected patient. The aim of our report is also to emphasize that early and correct diagnosis of Pneumocystis jirovecii pneumonia in immunocompromised HIV-uninfected patients is very important. Relevant oncologists should be alert to the risk of Pneumocystis jirovecii pneumonia in patients receiving R-CHOP chemotherapy.

Case report: Epigastric heteropagus twins and literature review.

Epigastric heteropagus twins are an extremely rare congenital anomaly of conjoined twins. We present a case of epigastric heteropagus twins who were diagnosed via prenatal ultrasound imaging: the fetus (or host) was connected to the abdominal wall of the parasite (the dependent portion), and an omphalocele was present. The male infant was delivered by cesarean section at 35 + 5 weeks gestation. The parasite lacked a head and heart and presented long bones of the limbs. After abdominal computed tomography, omphalocele repair, and parasite removal were surgically performed under general anesthesia. After discharge (follow-up, 3 months), the infant is currently growing well and is healing satisfactorily. Forty-one cases of epigastric heteropagus twins were retrieved from database searches: 38 good postoperative outcomes, 2 perioperative deaths, and 1 termination. The case highlights that even when parasites are massive in size, births can present good outcomes with suitable surgical treatment.

A global dataset of sequence, diversity and biosafety recommendation of arbovirus and arthropod-specific virus.

Arthropod-borne virus (arbovirus) and arthropod-specific virus (ASV) are viruses circulating amongst hematophagous arthropods that are broadly transmitted in ecological systems. Arbovirus may replicate in both vertebrates and invertebrates and some are known to be pathogenic to animals or humans. ASV only replicate in invertebrate arthropods yet they are basal to many types of arboviruses. We built a comprehensive dataset of arbovirus and ASV by curating globally available data from the Arbovirus Catalog, the arbovirus list in Section VIII-F of the Biosafety in Microbiological and Biomedical Laboratories 6th edition, Virus Metadata Resource of International Committee on Taxonomy of Viruses, and GenBank. Revealing the diversity, distribution and biosafety recommendation of arbovirus and ASV at a global scale is essential to the understanding of potential interactions, evolution, and risks associated with these viruses. Moreover, the genomic sequences associated with the dataset will enable the investigation of genetic patterns distinguishing the two groups, as well as aid in predicting the vector/host relationships of the newly discovered viruses.

Increased glymphatic system activity in patients with mild traumatic brain injury.

Purpose: This study aims to investigate the glymphatic system activity changes in patients with mild traumatic brain injury (mTBI), particularly in MRI-negative patients, using analysis along the perivascular space (ALPS) technology. Methods: A total of 161 mTBI patients (age: 15-92 years old) and 28 healthy controls (age: 15-84 years old) were included in this retrospective study. The mTBI patients were divided into MRI-negative and MRI-positive groups. ALPS index was calculated automatically using whole-brain T1-MPRAGE imaging and diffusion tensor imaging. The Student's t and chi-squared tests were performed to compare the ALPS index, age, gender, course of disease, and Glasgow Coma Scale (GCS) score between groups. Correlations among ALPS index, age, course of disease and GCS score were computed using Spearman's correlation analysis. Results: Increased activity of the glymphatic system was suggested in mTBI patients based on ALPS index analysis, including the MRI-negative patients. There was a significant negative correlation between the ALPS index and age. In addition, a weak positive correlation between the ALPS index and course of disease was also observed. On the contrary, there was no significant correlation between the ALPS index and sex nor between the ALPS index and GCS score. Conclusion: Our study demonstrated that the activity level of the glymphatic system was enhanced in mTBI patients, even when their brain MRI scans were negative. These findings may provide novel insights for understanding the pathophysiology of mild TBI.

Photosensitive Dye as an Ideal Peroxymonosulfate Activator for Efficient Self-Degradation: A Novel Idea of Using Waste to Treat Waste.

Commonly used peroxydisulfate (PS) or peroxymonosulfate (PMS) activation methods have been limited in their practical application due to certain drawbacks, such as high cost, high energy consumption and secondary pollution. In this study, a catalyst-free alizarin green (AG) self-activating PMS catalytic system was constructed based on photosensitization properties of dye, which ultimately achieved efficient degradation of the dye activator, also the target pollutant. Here, 52.5% of the 100 mL mixture of 10 mg/L AG decomposed within 60 min with 1 mM PMS under visible-light irradiation, thereby showing a strong pH adaptation. Mechanism of AG self-activating PMS was revealed that the photo-excited AG can effectively transfer photo-induced electrons to PMS for its activation, which generates reactive oxidizing species dominated by singlet oxygen (1O2), and supplemented by hydroxyl radical (•OH), superoxide radical (O2•-) and sulfate radical (SO4•-) to realize the efficient self-degradation of the dye pollutants. Moreover, such self-catalytic system operated well under natural sunlight irradiation, indicating the great application potential in the actual wastewater treatment. Herein, photosensitive dye acted as an ideal PMS activator realizing its efficient self-degradation, which provides a novel idea of "using waste to treat waste" for developing wastewater treatment process in a high-efficiency and low-consumption way.

Well-Dispersed Fe Nanoclusters for Effectively Increasing the Initial Coulombic Efficiency of the SiO Anode.

An efficient surface modification strategy is proposed to significantly increase the initial Coulombic efficiency (ICE) of SiO anode material. The SiO@Fe material with the Fe nanocluster homogeneously decorating on the SiO surface is successfully prepared by a chemical vapor deposition process. The well-dispersed Fe nanoclusters realize an Ohmic contact with lithium silicates, the commonly regarded irreversible lithiation product, which effectively lowers the electron conduction barriers and promotes the concomitant lithium-ion release of the lithium silicates upon the delithiation process, increasing the ICE of the SiO anode. The prepared SiO@Fe exhibits a much higher ICE of 87.2% compared to 64.4% of pristine SiO, with the largest increment (23%) never reported, except for the prelithiation, and delivers significantly enhanced cycling and rate performance. These findings provide an effective way to convert the "inert" phase to "active" which essentially increases the ICE of the electrode.

Development and Validation of a Nomogram for Predicting Tigecycline-Related Coagulopathy: A Retrospective Cohort Study.

Background: Although tigecycline is an effective drug against drug-resistant bacteria, it demonstrated a higher all-cause mortality than comparator antibiotics and a high incidence of coagulation disorders which can be accompanied by severe bleeding. At present, a predictive model for tigecycline-related coagulopathy is not readily available, and the prognostic value of coagulopathy in tigecycline-administered patients has not been elucidated. In this paper, we investigate the association between tigecycline-related coagulopathy and in-hospital mortality to develop a nomogram for the prediction of tigecycline-related coagulopathy. Methods: This retrospective cohort study includes 311 adults prescribed with tigecycline from 2018 to 2020. The primary cohort and validation cohort were constructed by dividing the participants in a ratio of 7:3. The endpoint is tigecycline-related coagulopathy, defined as a condition with no abnormality in coagulation prior to tigecycline application but developed the following symptoms upon prescription: activated partial thromboplastin time (APTT) extended by >10 s than the upper limit of normal (ULN), prothrombin time (PT) prolonged for >3 s than the ULN or reduced serum level of fibrinogen to <2.0 g/L. A predictive nomogram based on logistic regression was subsequently constructed. Results: Tigecycline intake for over 7 days, combined other antibiotics, initial PT, initial fibrinogen and estimated glomerular filtration rate (eGFR), are independent prognostic factors of tigecycline-related coagulopathy. The primary and validation cohort each has an area under the receiver operating characteristic curve (AUC) of 0.792 (0.732-0.851) and 0.730 (0.629-0.832) for nomogram, respectively. Furthermore, the fitted calibration curve illustrated adequate fit of the model, while the decision curve analysis demonstrated good clinical value. Survival curves showed a high mortality rate among patients with tigecycline-related coagulopathy. Conclusion: This nomogram exhibited helpful clinical value in predicting tigecycline-related coagulopathy that could reduce the high mortality rate of patients prescribed with tigecycline.

A discussion of microplastics in soil and risks for ecosystems and food chains.

Microplastics are among the major contaminations in terrestrial and marine environments worldwide. These persistent organic contaminants composed of tiny particles are of concern due to their potential hazards to ecosystem and human health. Microplastics accumulates in the ocean and in terrestrial ecosystems, exerting effects on living organisms including microbiomes, fish and plants. While the accumulation and fate of microplastics in marine ecosystems is thoroughly studied, the distribution and biological effects in terrestrial soil call for more research. Here, we review the sources of microplastics and its effects on soil physical and chemical properties, including water holding capacity, bulk density, pH value as well as the potential effects to microorganisms and animals. In addition, we discuss the effects of microplastics in combination with other toxic environmental contaminants including heavy metals and antibiotics on plant growth and physiology, as well as human health and possible degradation and remediation methods. This reflect is an urgent need for monitoring projects that assess the toxicity of microplastics in soil and plants in various soil environments. The prospect of these future research activities should prioritize microplastics in agro-ecosystems, focusing on microbial degradation for remediation purposes of microplastics in the environment.

A strategy for bioremediation of nuclear contaminants in the environment.

Radionuclides released from nuclear contamination harm the environment and human health. Nuclear pollution spread over large areas and the costs associated with decontamination is high. Traditional remediation methods include both chemical and physical, however, these are expensive and unsuitable for large-scale restoration. Bioremediation is the use of plants or microorganisms to remove pollutants from the environment having a lower cost and can be upscaled to eliminate contamination from soil, water and air. It is a cheap, efficient, ecologically, and friendly restoration technology. Here we review the sources of radionuclides, bioremediation methods, mechanisms of plant resistance to radionuclides and the effects on the efficiency of biological adsorption. Uptake of radionuclides by plants can be facilitated by the addition of appropriate chemical accelerators and agronomic management, such as citric acid and intercropping. Future research should accelerate the use of genetic engineering and breeding techniques to screen high-enrichment plants. In addition, field experiments should be carried out to ensure that this technology can be applied to the remediation of nuclear contaminated sites as soon as possible.

Nano Catalysis of Biofuels and Biochemicals from Cotinus coggygria Scop. Wood for Bio-Oil Raw Material.

Cotinus coggygria Scop. as a precious landscape shrub and a good afforestation species that is used in the pharmaceutical industry. In this paper, TG-FTIR, TG-DTG, and Py-GC/MS were used to study the biomaterials of Cotinus coggygria used as biofuels and biochemicals under the catalysis of nano-Mo/Fe2O3. The wood powder was extracted using a methanol/benzene solution, and the extract was analyzed by FTIR and GC-MS. The results showed that the pyrolysis products of Cotinus coggygria wood were rich in phenols, alcohols, and biofuels. The metal nano-Mo powder played a catalytic role in the interpretation of the gas in the species, where it accelerates gas products. Metal nano-Fe2O3 has a certain flame-retardant effect on the burning process of Cotinus coggygria wood, and the residual amount of pyrolysis is greater. The contents of the extract Formamide, 1-Hexanol, Levodopa, and 9,12-Octadecadienoic acid (Z,Z)- are not only widely used industrially but also play an important role in medicine. Cotinus coggygria is therefore an excellent biomaterial for biofuels and biochemicals.

Dietary vitamin A intakes of chinese children with adequate liver stores as assessed by the retinol isotope dilution technique.

BACKGROUND: We attempted to estimate dietary vitamin A requirements based on dietary vitamin A intake in well-nourished Chinese children with adequate liver vitamin A reserves. METHODS: A cross-sectional study was conducted in a kindergarten and an elementary school in Shiyan city, Hubei province of China from December 2009 to July 2010. After screening, 60 children (22 aged 4 ~ 6 y and 38 aged 7 ~ 9 y) were randomly subjected to a 3-d or 18-d deuterated-retinol-dilution (DRD) procedure to evaluate the vitamin A reserves in the body and liver. Dietary intakes of vitamin A were estimated from two (one in winter and one in summer) consecutive 3-day weighed food records and dietary recalls. RESULTS: The dietary vitamin A intakes were significantly correlated with vitamin A stores in the body and liver, but not with the serum level of retinol. The dietary vitamin A intakes were 476.9 ± 196.7 µg retinol equivalent (RE) (or 377.7 ± 166.2 µg retinol activity equivalent (RAE)) / day for 4 ~ 6 y children and 529.1 ± 87.2 µg RE/d (or 464.0 ± 81.1 µg RAE/d) for 7 ~ 9 y children with adequate liver vitamin A reserves. The estimated liver stores of vitamin A derived from both time points (3-d and 18-d) were similar. CONCLUSION: Adequate dietary vitamin A intakes among the well-nourished Chinese children were estimated to be 477 µg RE/d (95%CI 385 ~ 570) or 378 µg RAE/d (95%CI 304 ~ 441) for 4 ~ 6 y children and 529 µg RE/d (95%CI 500 ~ 560) or 464 µg RAE/d (95%CI 437 ~ 491) for 7 ~ 9 y children. Although it needs to be verified in a larger population of different regions in China, our results provide important data to establish the dietary requirement of vitamin A specifically for Chinese children.

Comparative Study on the Seepage Characteristics of Gas-Containing Briquette and Raw Coal in Complete Stress-Strain Process.

In this study, triaxial compression and seepage tests were conducted on briquette and raw coal samples using a coal rock mechanics-seepage triaxial test system (TAWD-2000) to obtain the complete stress-strain curves of the two samples under certain conditions. On this basis, the different damage forms of the two coal samples and the effect of their deformation and damage on their permeability were analyzed from the perspective of fine-scale damage mechanics. Moreover, the sensitivity of permeability to external variables and the suddenness of coal and gas outbursts were discussed. The results show that the compressive strength of raw coal is 27.1 MPa and the compressive strength of briquette is 17.3 MPa, the complete stress-strain curves of the two coal samples can be divided into four stages and show a good correspondence to the permeability-axial strain curves. Since briquette and raw coal have different structural properties, they present different damage mechanisms under load, thus showing great diversity in the permeability-axial strain curve, especially in the damage stage. The deformation affects the seepage characteristics of briquette mainly in the latter two stages, while it affects raw coal throughout the test. The four stages of the complete stress-strain seepage test of raw coal can well explain the four stages of coal and gas outburst process, i.e., preparation, initiation, development, and termination. Hence, the law of coal permeability to gas variation can be utilized for the coal and gas outburst prediction and forecast. The research results are valuable for exploring the real law of gas migration in coal seams.

The influence of increased precipitation and nitrogen deposition on the litter decomposition and soil microbial community structure in a semiarid grassland.

Litter decomposition is a major method in which nutrients are recycled, especially carbon and nitrogen elements, in terrestrial ecosystems. However, how the responses of litter quality and soil microbial communities to global changes alter litter decomposition remains unclear. A 4-year field manipulative experiment based on the litterbag method was conducted in a typical temperate semiarid grassland in China to explore how increased precipitation and nitrogen deposition affect decomposition processes via litter quality and soil microbial communities. Our results showed that water and nitrogen addition treatments could accelerate litter carbon release and promote mass loss through different pathways. Water addition had a direct positive effect on litter decomposition. However, nitrogen addition could indirectly promote litter decomposition by improving litter quality and increasing the bacterial and fungal ratios. The water addition treatment increased litter mass loss by 7.37 %, and the N addition treatments increased litter mass loss by 5.83 %-16.93 %. Moreover, water and nitrogen additions had antagonistic effects on litter decomposition. These findings revealed that litter quality and the soil bacterial to fungal ratio were the factors controlling litter decomposition. The changes in precipitation and nitrogen deposition will impact ecosystem carbon and nitrogen cycling by altering litter decomposition processes in semiarid grassland ecosystems under the context of climate change.

Scaffold hopping of celastrol provides derivatives containing pepper ring, pyrazine and oxazole substructures as potent autophagy inducers against breast cancer cell line MCF-7.

Three series of celastrol derivatives, namely, 6a-6i, 11a-11i and 15a-15i, were designed based on the scaffold hopping strategy. The derivatives were synthesized and biologically evaluated against five human tumor cell lines (i.e. A549, MCF-7, Bel7402, HT-29 and PC3) using MTT assay in vitro. Results showed that compound 11i exhibited apparent antiproliferative activity against the MCF-7 cell line with an IC50 value of 1.31 µM and could remarkably inhibit the colony formation of the MCF-7 cells. Transmission electron microscopy assay, monodansylcadaverine incorporation assay and the expression of LC3 A/B, p62 and Beclin-1 in MCF-7 cells suggested that the potent antiproliferative activity of compound 11i was mainly due to its autophagy-inducing effect. Moreover, compound 11i could arrest the MCF-7 cells in the G2/M phase by regulating the cell-cycle-related proteins Cdk-1 and Cyclin B1. In the zebrafish xenograft model, compound 11i could obviously inhibit the proliferation of the MCF-7 cells. Thus, compound 11i could serve as a promising lead compound for breast cancer therapy.