Design of Antiferromagnetic Second-Order Band Topology with Rotation Topological Invariants in Two Dimensions.

The existence of fractionally quantized topological corner charge serves as a key indicator for two-dimensional (2D) second-order topological insulators (SOTIs), yet it has not been experimentally observed in realistic materials. Here, based on effective model analysis and symmetry arguments, we propose a strategy for achieving SOTI phases with in-gap corner states in 2D systems with antiferromagnetic (AFM) order. We discover that the band topology originates from the interplay between intrinsic spin-orbital coupling and interlayer AFM exchange interactions. Using first-principles calculations, we show that the 2D AFM SOTI phase can be realized in (MnBi2Te4)(Bi2Te3)m films. Moreover, we demonstrate that the SOTI states are linked to rotation topological invariants under 3-fold rotation symmetry C3, resulting in fractionally quantized corner charge, i.e., n3|e| (mod e). Due to the great achievements in (MnBi2Te4)(Bi2Te3)m systems, our results providing reliable material candidates for experimentally accessible AFM SOTIs should draw intense attention.

Chiral-Flux-Phase-Based Topological Superconductivity in Kagome Systems with Mixed Edge Chiralities.

Recent studies have attracted intense attention on the quasi-2D kagome superconductors AV_{3}Sb_{5} (A=K, Rb, and Cs) where the unexpected chiral flux phase (CFP) associates with the spontaneous time-reversal symmetry breaking in charge density wave states. Here, commencing from the 2-by-2 charge density wave phases, we bridge the gap between topological superconductivity and time-reversal asymmetric CFP in kagome systems. Several chiral topological superconductor (TSC) states featuring distinct Chern numbers emerge for an s-wave or a d-wave superconducting pairing symmetry. Importantly, these CFP-based TSC phases possess unique gapless edge modes with mixed chiralities (i.e., both positive and negative chiralities), but with the net chiralities consistent with the Bogoliubov-de Gennes Chern numbers. We further study the transport properties of a two-terminal junction, using Chern insulator or normal metal leads via atomic Green's function method with Landauer-Büttiker formalism. In both cases, the normal electron tunneling and the crossed Andreev reflection oscillate as the chemical potential changes, but together contribute to plateau transmissions (1 and 3/2, respectively) that exhibit robustness against disorder. These behaviors can be regarded as the signature of a TSC hosting edge states with mixed chiralities.

The role of USP51 in attenuating chemosensitivity of lung cancer cells to cisplatin by regulating DNA damage response.

Lung cancer is the most frequent type of cancer affecting both men and women globally, and it is associated with a high mortality rate. It is clinically treated with cisplatin, a platinum-based drug that works by generating DNA lesions, which activates DNA damage response and induces cell death. However, chemoresistance by cancer cells limits the clinical usefulness of cisplatin as an anticancer drug. Here, we uncovered a role of ubiquitin-specific protease 51 (USP51) in the chemosensitivity of lung cancer cells to cisplatin by regulating DNA damage response. USP51 was more upregulated in lung cancer tissues of chemotherapy-resistant patients than those of chemotherapy-sensitive patients with adjacent, nontumor tissues. USP51 overexpression in lung cancer cells in vitro reduced γ-H2AX formation and promoted checkpoint kinase 1 (CHK1) phosphorylation, whereas USP51 knockdown showed opposite effects, indicating that USP51 played an important role in promoting DNA damage repair. Finally, USP51 knockdown weakened cisplatin resistance in A549/DDP cells and significantly suppressed tumor growth in vivo, suggesting that a USP51 inhibitor combined with cisplatin may be considered as an effective treatment strategy to eliminate drug-resistant lung cancer cells.

Transport Theory of Half-Quantized Hall Conductance in a Semimagnetic Topological Insulator.

Recently, a half-quantized Hall conductance (HQHC) plateau was experimentally observed in a semimagnetic topological insulator heterostructure. However, the heterostructure was metallic with a nonzero longitudinal conductance, which contradicts the common belief that quantized Hall conductance is usually observed in insulators. In this work, we systematically study the surface transport of a semimagnetic topological insulator with both gapped and gapless Dirac surfaces in the presence of dephasing process. In particular, we reveal that the HQHC is directly related to the half-quantized chiral current along the edge of a strongly dephasing metal. The Hall conductance keeps a half-quantized value for large dephasing strengths, while the longitudinal conductance varies with Fermi energies and dephasing strengths. Furthermore, we evaluate both the conductance and resistance as a function of the temperature, which is consistent with the experimental results. Our results not only provide the microscopic transport mechanism of the HQHC, but also are instructive for the probe of the HQHC in future experiments.

A review on recent advances in the applications of composite Fe3O4 magnetic nanoparticles in the food industry.

Fe3O4 magnetic nanoparticles (MNPs) have attracted tremendous attention due to their superparamagnetic properties, large specific surface area, high biocompatibility, non-toxicity, large-scale production, and recyclability. More importantly, numerous hydroxyl groups (-OH) on the surface of Fe3O4 MNPs can provide coupling sites for various modifiers, forming versatile nanocomposites for applications in the energy, biomedicine, and environmental fields. With the development of science and technology, the potential of nanotechnology in the food industry has also gradually become prominent. However, the application of composite Fe3O4 MNPs in the food industry has not been systematically summarized. Herein, this article reviews composite Fe3O4 MNPs, including their properties, modifications, and physical functions, as well as their applications in the entire food industry from production to processing, storage, and detection. This review lays a solid foundation for promoting food innovation and improving food quality and safety.

Ultrafast exciton delocalization and localization dynamics of a perylene bisimide quadruple π-stack: a nonadiabatic dynamics simulation.

Unraveling the photogenerated exciton dynamics of π-stacked molecular aggregates is of great importance for both fundamental studies and industrial applications. Among various π-stacked molecular aggregates, perylene tetracarboxylic acid bisimide (PBI) based aggregates are regarded as one of the prototypes due to their inherent high fluorescence quantum yield and excellent photostability and flexibility in controlling intermolecular forces via chemical modifications. However, the exciton dynamics of these PBI based aggregates remain elusive up to now. In this work, we have first employed LR-TDDFT-based nonadiabatic dynamics simulations and static electronic structure calculations to investigate the ultrafast exciton dynamics of a newly synthesized perylene bisimide quadruple (PBQ) π-stack. Upon photoexcitation, the S6 to S10 states are the most likely populated excited states, which can be regarded as a combination of local excited (LE) excitons and charge transfer (CT) excitons of those four PBI chromophores. Then, the excited PBQ π-stack relaxes ultrafast to the lowest lying excited S1 state within 500 fs, which is accompanied by the complicated exciton conversion as well as exciton localization/delocalization dynamics. In short, the initially populated hybrid LE and CT excitons convert to the LE excitons of B/C and A/D, in which the LE excitons of B/C contribute the most (∼0.44) while the LE excitons of A/D also have minor contributions (0.21), indicating the formation of the localized excimer state. We use the notations A/B/C/D here to represent the four PBI fragments of PBQ π-stacks along the direction perpendicular to the PBI molecular plane. Additionally, using a recently defined root mean square deviation (RMSD) of electron and hole spatial distributions along three Cartesian coordinates, we could investigate the exciton localization/delocalization dynamics in a quantitative way. Our simulation results indicate that the photoinduced electrons and holes of the PBQ π-stack exhibit an ultrafast localization(∼10 fs)-delocalization(∼60 fs)-localization(∼200 fs) dynamics, during which both LE and CT excitons play crucial roles. Our present work is not only consistent with previous experimental studies, but also provides more detailed insights into the relevant processes, which might be useful for the future design of PBI based optoelectronic devices with improved performances.

Response of environmental factors to attenuation of toluene in vadose zone.

Contaminated groundwater migrates in reverse direction under capillary force in vadose zone, and the attenuation process of pollutant adsorption and microbial degradation changes the environment of vadose zone. In this study, the response of toluene to environmental factors during reverse migration and attenuation of toluene from aquifer to vadose zone was studied by column experiment and experimental data analysis. The changes of environmental factors, including potential of hydrogen (pH), dissolved oxygen (DO), and oxidation-reduction potential (ORP), and toluene concentration were monitored by soil column experiment under sterilized and non-sterilized conditions. The 16S rRNA molecular biological detection technology was used to quantitatively analyze the impact of microbial degradation on the environment. Finally, the correlation between environmental factors and concentration in the attenuation process of toluene in the vadose zone was quantitatively studied by Pearson Correlation Coefficient (PCC) and multivariate statistical equation. The results showed that pH was primarily affected by microbial degradation, and DO and ORP were primarily affected by both adsorption and microbial degradation. The attenuation of toluene was divided into two stages: adsorption dominated (0~26 d) and microbial degradation dominated (26~55 d). The degradation amounts of microorganisms at each position in the non-sterilized column from bottom to top were 9.37%, 55.34%, 68.64%, 75.70%, 66.03% and 42.50%. At the same time, the article proposes for the first time that there is an obvious functional relationship between environmental factors (DO, ORP, pH), time (t) and concentration (CToluene):CToluene=C0+A100t+Bα+Cß+D100γ, (α,ß,γ are the pH, DO and ORP of capillary water, respectively; A, B, C and D are all undetermined coefficients), R2 > 0.95. The results of this study may facilitate the use of simple and easy-to-obtain environmental factors to characterize the dynamic process of pollutant concentration changes.

Response relationship of environmental factors caused by toluene concentration during leaching of capillary zone.

Due to the leaching of capillary water, the petroleum pollutants initially trapped in vadose zone may migrate to lower aquifer, thus increasing the risk of groundwater pollution. In order to explore the effect of capillary leaching on toluene-contaminated soil and the relationship between toluene concentration (TC) and environmental factors (EFs) during the leaching process, the sterilized and non-sterilized soil column experiments were designed. The EFs were used to estimate TC. The results showed that the difference between leaching and volatilization rates directly determined the changing trend of toluene concentration in capillary water. The toluene concentration in the medium always showed decreasing trend due to leaching. The indigenous microbial community structure of the non-sterilized soil column was analyzed by 16S rRNA sequencing. It was found that indigenous microorganisms could degrade toluene after 33.0 days of acclimatation. The microbial population was dominated by bacteria, among them the Ellin6055 strain and Pseudomonas, Pseudoxanthomonas, Cupriavidus, Bdellovibrio, Sphingobium, Phenylobacterium, Ramlibacter, Bradyrhizobium, Shinella genera. The Pseudomonas was the most crucial bacterial genus that degraded toluene. Indigenous microbial degradation was the fundamental reason for strong response relationship. Furthermore, we suggested a relationship of function between environmental factors (pH, DO, ORP) and time (t) for toluene attenuation: C0+ln(eAtαBγCß)=CToluene, (α, ß, γ represent the pH, DO, and ORP in leaching capillary water, respectively; A, B, and C represent undetermined coefficients), and the fitting coefficient R2 > 0.950. This relationship can only characterize the attenuation process of capillary zone leaching on toluene. However, it may still be utilized to give a theoretical foundation for understanding the dynamic of pollutant concentration change processes under specific environmental factors.

Knockdown of circFOXO3 ameliorates cigarette smoke-induced lung injury in mice.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) remains a prevalent chronic airway inflammatory disease. Circular RNAs (circRNAs) are associated with inflammation regulation; therefore, we examined distinct effects of circRNA FOXO3 (circFOXO3) against pneumonic inflammatory processes in COPD. METHODS: We first quantified and localized circFOXO3 in mouse lung epithelial cell line MLE12 by quantitative reverse-transcription PCR and in situ hybridization. Next, circFOXO3 was suppressed by therapeutic administration of circFOXO3 knockdown lentivirus in mice exposed to air or cigarette smoke (CS) for 12 weeks, and several hallmarks of COPD were evaluated. RESULTS: We noticed that circFOXO3 is upregulated in CS-exposed lungs and cigarette smoke extract (CSE)-treated murine alveolar epithelial cells. Knockdown of circFOXO3 attenuated the release of CXCL1 and IL-6 as well as inflammatory processes in the lungs of CS-exposed mice. In addition, we identified miR-214-3p as a circFOXO3-targeted microRNA. MiR-214-3p overexpression exerted protective effects against pneumonic inflammation after CS exposure. Silencing of circFOXO3 downregulated IKK-ß mRNA (miR-214-3p's target), resulting in the dysfunction of the NF-κB signaling pathway and attenuation of CSE-induced inflammatory-cytokine expression. CONCLUSIONS: Collectively, these findings reveal a crucial function of circFOXO3 in the pathological remodeling related to CS-induced inflammatory processes. Hence, circFOXO3 might be a good target for the treatment of inflammatory disorders similar to CS-induced lung inflammation.

Ultrafast channel I and channel II charge generation processes at a nonfullerene donor-acceptor PTB7:PDI interface is crucial for its excellent photovoltaic performance.

Nonfullerene organic solar cells have received much attention in recent years due to their low cost, high absorption coefficient and excellent synthetic flexibility. However, the microscopic photoinduced dynamics at corresponding donor-acceptor interfaces remains unclear. In this work, we have firstly employed state-of-the-art TDDFT-based nonadiabatic dynamics simulations in combination with static electronic structure calculations to explore the ultrafast photoinduced dynamics at a typical nonfullerene donor-acceptor PTB7:PDI interface using a minimal model system (172 atoms). Upon excitation with specific wavelength of light, both PTB7 and PDI can be locally excited to generate |PTB7* and |PDI* excitons due to their high absorption ability and significant overlap in absorption spectrum. After that, these localized excitons gradually convert to charge transfer exciton |PTB7+PDI-, while another |PTB7-PDI+ charge transfer exciton is not involved in the whole process. Along with the exciton conversion, electron transfer from PTB7 to PDI (channel I charge generation) and the hole transfer from PDI to PTB7 (channel II charge generation) occurs simultaneously with time constants of 643 fs and 549 fs respectively. In the same time, D index that measures the centroid distance of electron and hole increases from 1.0 Å to 4.0 Å, which clearly reflects a charge transfer process at the interface. Our present work provides solid evidence that both channel I and channel II charge generation processes play important roles at PTB7:PDI interface, which could be helpful for the design of novel nonfullerene solar cells with better photovoltaic performance.

MiR-501-3p functions as a tumor suppressor in non-small cell lung cancer by downregulating RAP1A.

MicroRNA-501-3p (miR-501-3p) has been reported to play tumor-suppressive roles in different cancers; however, its expression pattern and biological function in non-small cell lung cancer (NSCLC) remain unknown. In this study, we noted downregulation of miR-501-3p in NSCLC tissues and cell lines. Functional assays showed that overexpression of miR-501-3p suppressed NSCLC cell proliferation, clonogenicity, migration, and invasion. Moreover, miR-501-3p overexpression attenuated in vivo tumor growth in a nude mouse model. In terms of the mechanism, RAP1A was identified as a novel target of miR-501-3p. Overexpression of RAP1A strongly attenuated the inhibitory effects of miR-501-3p on the capacity of NSCLC cells for proliferation and motility. In the clinical samples of NSCLC, miR-501-3p levels negatively correlated with RAP1A expression, which was upregulated in NSCLC. Collectively, these results indicate that miR-501-3p acts as a tumor suppressor in NSCLC by directly targeting RAP1A mRNA and may serve as a theranostic biomarker for patients with NSCLC.

Long-Term Outcomes of Patients with Self-Expandable Transcatheter Heart Valve Embolized in the Aorta.

This study assesses the long-term outcomes of patients who suffered from self-expandable transcatheter heart valve (THV) embolized in the aorta in transcatheter aortic valve implantation (TAVI).We retrospectively reviewed the patients with self-expandable THV embolized in the aorta. Follow-up computed tomography was performed to assess the THV migration, struct fractures, and device-related aortic complications.Of the 539 TAVI patients, 11 suffered from self-expandable THV embolized in the aorta. Two patients underwent open-heart surgery to remove the embolized THVs in the ascending aorta. Embolized THVs were repositioned in the aortic arch distal to the left subclavian artery (n = 3) and the thoracic descending aorta (n = 6). Three patients died during a median follow-up time of 40 months. The remaining eight survivors presented with New York Heart Association functional class I or II at the last follow-up. Degeneration of embolized prostheses with thick leaflets and rolled cusp edges was observed in three patients. There was no evidence of valve migration, strut fracture, prosthesis-associated aortic complication, and thrombosis attached on embolized valve for all patients with THVs repositioned in the aorta.Self-expandable THV embolization can be effectively managed in TAVI. Although some embolized valves exhibited leaflet degeneration, the long-term safety of repositioning embolized self-expandable THV in the aorta is assured.

"On-The-Fly" Non-Adiabatic Dynamics Simulations on Photoinduced Ring-Closing Reaction of a Nucleoside-Based Diarylethene Photoswitch.

Nucleoside-based diarylethenes are emerging as an especial class of photochromic compounds that have potential applications in regulating biological systems using noninvasive light with high spatio-temporal resolution. However, relevant microscopic photochromic mechanisms at atomic level of these novel diarylethenes remain to be explored. Herein, we have employed static electronic structure calculations (MS-CASPT2//M06-2X, MS-CASPT2//SA-CASSCF) in combination with non-adiabatic dynamics simulations to explore the related photoinduced ring-closing reaction of a typical nucleoside-based diarylethene photoswitch, namely, PS-IV. Upon excitation with UV light, the open form PS-IV can be excited to a spectroscopically bright S1 state. After that, the molecule relaxes to the conical intersection region within 150 fs according to the barrierless relaxed scan of the C1-C6 bond, which is followed by an immediate deactivation to the ground state. The conical intersection structure is very similar to the ground state transition state structure which connects the open and closed forms of PS-IV, and therefore plays a crucial role in the photochromism of PS-IV. Besides, after analyzing the hopping structures, we conclude that the ring closing reaction cannot complete in the S1 state alone since all the C1-C6 distances of the hopping structures are larger than 2.00 Å. Once hopping to the ground state, the molecules either return to the original open form of PS-IV or produce the closed form of PS-IV within 100 fs, and the ring closing quantum yield is estimated to be 56%. Our present work not only elucidates the ultrafast photoinduced pericyclic reaction of the nucleoside-based diarylethene PS-IV, but can also be helpful for the future design of novel nucleoside-based diarylethenes with better performance.

Higher-Order Topological Insulators in Quasicrystals.

Current understanding of higher-order topological insulators (HOTIs) is based primarily on crystalline materials. Here, we propose that HOTIs can be realized in quasicrystals. Specifically, we show that two distinct types of second-order topological insulators (SOTIs) can be constructed on the quasicrystalline lattices (QLs) with different tiling patterns. One is derived by using a Wilson mass term to gap out the edge states of the quantum spin Hall insulator on QLs. The other is the quasicrystalline quadrupole insulator (QI) with a quantized quadrupole moment. We reveal some unusual features of the corner states (CSs) in the quasicrystalline SOTIs. We also show that the quasicrystalline QI can be simulated by a designed electrical circuit, where the CSs can be identified by measuring the impedance resonance peak. Our findings not only extend the concept of HOTIs into quasicrystals but also provide a feasible way to detect the topological property of quasicrystals in experiments.

Astaxanthin Attenuates Fish Oil-Related Hepatotoxicity and Oxidative Insult in Juvenile Pacific White Shrimp (Litopenaeus vannamei).

The present study investigated the effect of dietary astaxanthin (AX) on the growth performance, antioxidant parameters, and repair of hepatopancreas damage in Pacific white shrimp (Litopenaeus vannamei). To evaluate the hepatopancreas protective function of AX in shrimps, we compared the effect of five isonitrogenous and isoenergetic diets under oxidized fish oil conditions with varying AX levels during the 50-day experimental period. The formulated diets were as follows: (i) OFO (oxidized fish oil); (ii) OFO/AX150 (oxidized fish oil + AX150 mg/kg); (iii) OFO/AX250 (oxidized fish oil + AX250 mg/kg); (iv) OFO/AX450 (oxidized fish oil + AX450 mg/kg); and, (v) control group (fresh fish oil). Results showed that the oxidized fish oil with 275.2 meq/kg peroxide value (POV) resulted in a substantial decrease in the final body weight of L. vannamei (P > 0.05) and induced some visible histopathological alterations in the hepatopancreas. Growth performance was significantly higher in shrimps fed with the OFO/AX450 diet than those fed with the OFO diet (p < 0.05). However, no significant difference was observed when the OFO/AX450 diet was compared to the control diet containing fresh fish oil (p > 0.05). Moreover, shrimps under the OFO/AX450 diet displayed a significant improvement in hepatopancreatic health and showed a reduction of malondialdehyde (MDA) compared to those under the OFO diet (p < 0.05). Dietary AX improved the antioxidant capacity of L. vannamei by increasing the catalase (CAT) activity in the hemolymph. Acute salinity change test showed a higher shrimp survival rate under OFO/AX450 diet than the OFO diet (p < 0.05), suggesting that AX can contribute to enhanced stress tolerance. In conclusion, our data suggest that AX confers dose-dependent protection against OFO-induced oxidative insults and hepatopancreatic damage in shrimp.

Comparison of Procedural and 1-Year Clinical Results of Transcatheter Aortic Valve Implantation Using Prostheses with Different Design of Support Frame.

Our study aimed to investigate whether the frame design of transcatheter heart valve (THV) affects the procedural and clinical results of transcatheter aortic valve implantation (TAVI).We retrospectively reviewed 163 patients with aortic stenosis who underwent TAVI using different types of THV (Edwards SAPIEN, n = 31; Venus-A, n = 63; and J-Valve, n = 69). The procedural outcomes and follow-up results for 1-year were compared among groups.The patients who underwent TAVI using J-Valve had a higher mean transaortic pressure gradient than those using SAPIEN or Venus-A after TAVI (1-year follow-up; P = 0.017, P < 0.001, respectively), whereas no difference was observed between the patients with SAPIEN and Venus-A prosthesis (P = 0.150). The incidence of permanent pacemaker implantation was highest in patients with Venus-A (19.0%), followed by SAPIEN (9.7%), and lowest in J-Valve (4.3%) (P = 0.025). No difference was observed in the 30-day mortality rate among the groups (P = 1.000). Moreover, Kaplan-Meier survival analysis revealed that there was no significant difference in the 1-year cumulative patient survival rate among three patient cohorts (log-rank, P = 0.850).The frame design of THVs could affect the valve-related hemodynamics and the incidence of permanent pacemaker implantation in TAVI, whereas it did not influence the survival rate of TAVI patients during 1-year follow-up period. All three THVs provided a convincing short-term outcome for TAVI patients.

Retracted: Long noncoding RNA MEG3 inhibits proliferation and migration but induces autophagy by regulation of Sirt7 and PI3K/AKT/mTOR pathway in glioma cells.

Glioma is a common primary brain tumor with high mortality rate and poor prognosis. Long noncoding RNA maternally expressed gene 3 (MEG3) is a tumor suppressor in diverse cancer types. However, the role of MEG3 in glioma remains unclear. We aimed to explore the effects of MEG3 on U251 cells as well as the underlying mechanisms. U251 cells were stably transfected with different recombined plasmids to overexpress or silence MEG3. Effects of aberrantly expressed MEG3 on cell viability, migration, apoptosis, expressions of apoptosis-associated and autophagy-associated proteins, and phosphorylated levels of key kinases in the PI3K/AKT/mTOR pathway were all evaluated. Then, messenger RNA (mRNA) and protein expression of Sirt7 in cells abnormally expressing MEG3 were estimated. In addition, effects of abnormally expressed MEG3 and Sirt7 on U251 cells were determined to reveal the underlying mechanism of MEG3-associated modulation. Cell viability and migration were significantly reduced by MEG3 overexpression whereas cell apoptosis as well as Bax and cleaved caspase-3/-9 proteins were obviously induced. Beclin-1 and LC3-II/LC3-I were upregulated and p62 was downregulated in MEG3 overexpressed cells. In addition, the autophagy pharmacological inhibitor (3-methyladenine, 3-MA) affected the effect of MEG3 overexpression on cell proliferation. Furthermore, the phosphorylated levels of key kinases in the PI3K/AKT/mTOR pathway were all reduced by MEG3 overexpression. Sirt7 was positively regulated by MEG3 expression, and effects of MEG3 overexpression on U251 cells were ameliorated by Sirt7 silence. MEG3 suppressed cell proliferation and migration but promoted autophagy in U251 cells through positively regulating Sirt7, involving in the inhibition of the PI3K/AKT/mTOR pathway.

Zn(II)-curcumin solid dispersion impairs hepatocellular carcinoma growth and enhances chemotherapy by modulating gut microbiota-mediated zinc homeostasis.

Zinc(II) complexes of curcumin display moderate cytotoxicity towards cancer cells at low micromolar concentrations. However, the clinical use of zinc(II) complexes is hampered by hydrolytic insolubility and poor bioavailability and their anticancer mechanisms remain unclear. Here, we investigated the efficacy and mechanism of action of a polyvinylpyrrolidone (PVP-k30)-based solid dispersion of Zn(II)-curcumin (ZnCM-SD) against hepatocellular carcinoma (HCC) in vitro and in vivo. In vitro assays revealed ZnCM-SD not only reduced the viability of HepG2 cells and SK-HEP1 cells in a dose-dependent manner, but also potently and synergistically enhanced cell growth inhibition and cell death in response to doxorubicin by regulating cellular zinc homeostasis. ZnCM-SD was internalized into the cells via non-specific endocytosis and degraded to release curcumin and Zn2+ ions within cells. The anticancer effects also occur in vivo in animals following the oral administration of ZnCM-SD, without significantly affecting the weight of the animals. Interestingly, ZnCM-SD did not reduce tumor growth or affect zinc homeostasis in HepG2-bearing mice after gut microbiome depletion. Moreover, administration of ZnCM-SD alone or in combination with doxorubicin significantly attenuated gut dysbiosis and zinc dyshomeostasis in a rat HCC model. Notably, fecal microbiota transplantation revealed the ability of ZnCM-SD to regulate zinc homeostasis and act as a chemosensitizer for doxorubicin were dependent on the gut microbiota. The crucial role of the gut microbiota in the chemosensitizing ability of ZnCM-SD was confirmed by broad-spectrum antibiotic treatment. Collectively, ZnCM-SD could represent a simple, well-tolerated, safe, effective therapy and function as a novel chemosensitizing agent for cancer.

Facile synthesis of magnetic zinc metal-organic framework for extraction of nitrogen-containing heterocyclic fungicides from lettuce vegetable samples.

We present a simple method for the fabrication of a magnetic amino-functionalized zinc metal-organic framework based on a magnetic graphene oxide composite. The resultant framework exhibited a porous 3D structure, high surface area and good adsorption properties for nitrogen-containing heterocyclic fungicides. The adsorption process and capacity indicated that the primary adsorption mechanism might be hydrogen bonding and π-π conjugation. In addition, an optimized protocol for magnetic solid phase extraction was developed (such as adsorbent content, pH, and desorption solvent), and utilized for the extraction of nitrogen-containing heterocyclic fungicides from vegetable samples. Quantitation by high performance liquid chromatography coupled with tandem mass spectrometry offered a detection limit of 0.21-1.0 µg/L (S/N = 3) with correlation coefficients larger than 0.9975. These results demonstrate that magnetic amino-functionalized zinc metal-organic framewor is a promising adsorbent for the extraction and quantitation of nitrogen-containing heterocyclic fungicides.

A beta-cyclodextrin-functionalized magnetic metal organic framework for efficient extraction and determination of prochloraz and triazole fungicides in vegetables samples.

A ß-cyclodextrin-functionalized magnetic zinc-metal organic framework (M-MOF/ß-CD) was synthesized via a facile one-pot reaction. M-MOF/ß-CD was used as a magnetic porous absorbent for the extraction and determination of prochloraz and three triazole fungicides in vegetable samples. M-MOF/ß-CD was prepared by creating MOF layers on the surface of a Fe3O4-graphene oxide (GO) nanocomposite and bonding them with ß-CD molecules. Characterization suggested that a 3D porous structure was formed, with M-MOF/ß-CD exhibiting high superparamagnetism and a large surface area. As a new strategy, integrating MOFs with Fe3O4-GO could improve their water-resistance and mechanical strength by providing a rigid nanosupport interface. Combining M-MOF and ß-CD resulted in excellent selective adsorption capacities for prochloraz and three triazole fungicides. The static adsorption process was evaluated and the results were in good agreement with the Freundlich model. Subsequently, M-MOF/ß-CD was applied to extracting prochloraz and triazole fungicides from tomato and lettuce vegetables, followed by HPLC-MS/MS determination. The limits of detection for the above fungicides were found to be 0.25-1.0 µg/L at a signal-to-noise ratio of 3, with spiked recoveries of 74.13%-119.83%, indicating that M-MOF/ß-CD was promising for application to the extraction and determination of fungicides in complex matrices.