Recent progress in magnetic polydopamine composites for pollutant removal in wastewater treatment.

Various water pollution issues pose a significant threat to human water safety. Magnetic polydopamine composites (MPCs), which can be separated by magnetic fields after the adsorption process, exhibit outstanding adsorption capacity and heterogeneous catalytic properties, making them promising materials for water treatment applications. In particular, by modifying the polydopamine (PDA) coating, MPCs can acquire enhanced high reactivity, antibacterial properties, and biocompatibility. This also provides an attractive platform for further fabrication of hybrid materials with specific adsorption, catalytic, antibacterial, and water-oil separation capabilities. To systematically provide the background knowledge and recent research advances in MPCs, this paper presents a critical review of MPCs for water treatment in terms of both structure and mechanisms of effect in applications. Firstly, the impact of different PDA positions within the composite structure is investigated to summarize the optimization of properties contributed by PDA when acting as the shell, core, or bridge. The roles of various secondary modifications of magnetic materials by PDA in addressing water pollution problems are explored. It is anticipated that this work will be a stimulus for further research and development of magnetic composite materials with real-world application potential.

Kaempferol regulates the thermogenic function of adipocytes in high-fat-diet-induced obesity via the CDK6/RUNX1/UCP1 signaling pathway.

Activation of adipose tissue thermogenesis is a promising strategy in the treatment of obesity and obesity-related metabolic disorders. Kaempferol (KPF) is a predominant dietary flavonoid with multiple pharmacological properties, such as anti-inflammatory and antioxidant activities. In this study, we sought to characterize the role of KPF in adipocyte thermogenesis. We demonstrated that KPF-treated mice were protected from diet-induced obesity, glucose tolerance, and insulin resistance, accompanied by markedly increased energy expenditure, ex vivo oxygen consumption of white fat, and increased expression of proteins related to adaptive thermogenesis. KPF-promoted beige cell formation is a cell-autonomous effect, since the overexpression of cyclin-dependent kinase 6 (CDK6) in preadipocytes partially reversed browning phenotypes observed in KPF-treated cells. Overall, these data implicate that KPF is involved in promoting beige cell formation by suppressing CDK6 protein expression. This study provides evidence that KPF is a promising natural product for obesity treatment by boosting energy expenditure.

Acteoside improves adipocyte browning by CDK6-mediated mTORC1-TFEB pathway.

Adipocyte browning increases energy expenditure by thermogenesis, which has been considered a potential strategy against obesity and its related metabolic diseases. Phytochemicals derived from natural products with the ability to improve adipocyte thermogenesis have aroused extensive attention. Acteoside (Act), a phenylethanoid glycoside, exists in various medicinal or edible plants and has been shown to regulate metabolic disorders. Here, the browning effect of Act was evaluated by stimulating beige cell differentiation from the stromal vascular fraction (SVF) in the inguinal white adipose tissue (iWAT) and 3T3-L1 preadipocytes, and by converting the iWAT-SVF derived mature white adipocytes. Act improves adipocyte browning by differentiation of the stem/progenitors into beige cells and by direct conversion of mature white adipocytes into beige cells. Mechanistically, Act inhibited CDK6 and mTOR, and consequently relieved phosphorylation of the transcription factor EB (TFEB) and increased its nuclear retention, leading to induction of PGC-1α, a driver of mitochondrial biogenesis, and UCP1-dependent browning. These data thus unveil a CDK6-mTORC1-TFEB pathway that regulates Act-induced adipocyte browning.

Red Flag on Electrocardiogram Findings in a Patient With Lung Cancer.

This case report describes a patient in their early 70s with sudden onset squeezing precordial chest pain, back pain, and nausea, and a history of long-term lung cancer treatment.

Hyperoside prevents high-fat diet-induced obesity by increasing white fat browning and lipophagy via CDK6-TFEB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Hypericum perforatum L. (genus Hypericum, family Hypericaceae) is a flowering plant native to Europe, North Africa and Asia, which can be used in the treatment of psychiatric disorder, cardiothoracic depression and diabetes. Crataegus pinnatifida Bunge (genus Crataegus pinnatifida Bunge, family Rosaceae) was another traditional Chinese medicine for treating hyperlipidemia. Hyperoside (Hype), a major flavonoid glycoside component of Hypericum perforatum L. and Crataegus pinnatifida Bunge, possesses multiple physiological activities, such as anti-inflammatory and antioxidant effects. However, the role of Hype on obesity and related metabolic diseases still needs to be further investigated. AIM OF THE STUDY: We explored the effect of Hype on high-fat diet (HFD)-induced obesity and its metabolic regulation on white fat tissues. MATERIALS AND METHODS: In vivo four-week-old male C57BL/6J mice were randomly assigned to vehicle (0.5% methycellulose) and Hype (80 mg/kg/day by gavage) group under a normal chow diet (NCD) or HFD for 8 weeks. In vitro, 3T3-L1 preadipocyte cell line and primary stromal vascular fraction (SVF) cells from inguinal white adipose tissue (iWAT) of mice were used to investigate the molecular mechanisms of Hype regulation on adipocyte energy metabolism. RESULTS: Hype treatment in vivo promotes UCP1-dependent white to beige fat transition, increases glucose and lipid metabolism, and resists HFD-induced obesity. Meanwhile, Hype induces lipophagy, a specific autophagy that facilitates the breakdown of lipid droplets, and blocking autophagy partially reduces UCP1 expression. Mechanistically, Hype inhibited CDK6, leading to the increased nuclear translocation of TFEB, while overexpression of CDK6 partially reversed the enhancement of UCP1 by Hype. CONCLUSIONS: Hype protects mice from HFD-induced obesity by increasing energy expenditure of white fat tissue via CDK6-TFEB pathway.

Polydopamine-mediated modification of ZIF-8 onto magnetic nanoparticles for enhanced tetracycline adsorption from wastewater.

Magnetic nanoparticle materials which could be used to remove tetracycline were confined seriously due to their poor stability and unsatisfactory reusability. Here, we facilely prepared novel zeolitic imidazolate framework-8 (ZIF-8) functionalized magnetic nanoparticles (Fe3O4@PDA-ZIF-8) adsorbent utilizing polydopamine as a bond to establish a connection between zeolitic imidazolate framework-8 and Fe3O4, which could improve the stability of magnetic nanoparticles and enhance the tetracycline adsorption capacity simultaneously. The prepared nanocomposites were characterized and their TC adsorption abilities under various experiment conditions (contact time, TC initial concentration and pH values) were also investigated. Experimental results proved that the prepared adsorbent showed superior TC adsorption capacities (92.01 mg/g at pH = 7). Further, the adsorption mechanisms were comprehensively studied and the prepared adsorbent showed satisfactory stability and reusability during the cycle experiment. Altogether, our findings provided a feasible way to design and construct functional magnetic MOF materials for enhancing tetracycline adsorption from wastewater.

Rapid chromium reduction by metal-free organic polymer photocatalysis via molecular engineering.

The conversion of hexavalent chromium (Cr(VI)), a highly poisonous heavy metal found in natural environment, to less poisonous trivalent chromium (Cr(III)) has attracted a lot of interest. However, little interest has been paid to the development of metal-free catalysts. Here, we demonstrate for the first time a molecular engineering strategy to synthesize a range of donor-acceptor conjugated polymer photocatalysts, which can significantly increase the reduction efficiency of Cr(VI) by a factor of 5.2, corresponding to a significant change in the reduction reaction rate constant (from 0.0337 to 0.1740 min-1). In addition, the apparent quantum efficiency (AQE) of Cr(VI) removal was obtained, and the optimized photocatalyst (Py-SO1) could achieve the highest apparent quantum efficiency at wavelength of 420 nm in those samples. Despite the narrow light absorption of Py-SO1 polymer, its excellent exciton separation efficiency and efficient electron output enabled it to achieve excellent performance in photoreduction of Cr(VI), surpassing that of the reported metal-free photocatalysts. The results show that the present work provides a new perspective for designing suitable environmental remediation catalysts based on molecular engineering strategies.

Dendritic Hydrogels with Robust Inherent Antibacterial Properties for Promoting Bacteria-Infected Wound Healing.

Bacterial infections are a common problem associated with wound treatment that imposes a significant burden on healthcare systems and patients. As a result, healthcare providers urgently need new treatment strategies to protect people. Hydrogel biomaterials with inherent antimicrobial properties offer an attractive and viable solution to this issue. Here, for the first time, we have developed a new efficient synthetic strategy to prepare cationic hydrogels (PHCI) with intrinsically efficient antimicrobial properties by chemically cross-linking trans-1,4-cyclohexanediamine with 1,3-dibromo-2-propanol using a condensation reaction without the use of toxic cross-linking agents. As expected, the prepared PHCI hydrogel possessed an inherent antibacterial ability that can adsorb and kill Staphylococcus aureus and Escherichia coli electrostatically. Notably, in vivo experiments on normal and diabetic rat models confirmed that the PHCI hydrogel can quickly stop bleeding, efficiently kill bacteria, promote the conversion of macrophages from the proinflammatory M1 phenotype to the repaired M2 phenotype, and accelerate collagen deposition and blood vessel formation, thereby achieving rapid wound healing. Overall, this work presents an effective antibacterial dressing that might provide a facile but effective approach for clinical wound management.

CDK6 increases glycolysis and suppresses autophagy by mTORC1-HK2 pathway activation in cervical cancer cells.

Cervical carcinoma is a leading malignant tumor among women worldwide, characterized by the dysregulation of cell cycle. Cyclin-dependent kinase 6 (CDK6) plays important roles in the cell cycle progression, cell differentiation, and tumorigenesis. However, the role of CDK6 in cervical cancer remains controversial. Here, we found that loss of CDK6 in cervical adenocarcinoma HeLa cell line inhibited cell proliferation but induced apoptosis as well as autophagy, accompanied by attenuated expression of mammalian target of rapamycin complex 1 (mTORC1) and hexokinase 2 (HK2), reduced glycolysis, and production of protein, nucleotide, and lipid. Similarly, we showed that CDK6 knockout inhibited the survival of CDK6-high CaSki but not CDK6-low SiHa cervical cancer cells by regulation of glycolysis and autophagy process. Collectively, our studies indicate that CDK6 is a critical regulator of human cervical cancer cells, especially with high CDK6 level, through its ability to regulate cellular apoptosis and metabolism. Thus, inhibition of CDK6 kinase activity could be a powerful therapeutic avenue used to treat cervical cancers.

UV-assisted ultrafast construction of robust Fe3O4/polydopamine/Ag Fenton-like catalysts for highly efficient micropollutant decomposition.

Fenton-like catalysts represent a family of promising materials to degrade micropollutants from contaminated water. However, the practical applications of Fenton-like catalysts are mainly limited by low catalytic degradation efficiency and stability. Herein, for the first time, rapid fabrication of Ag-decorated Fe3O4/polydopamine (FPA) microspheres was achieved via the help of UV irradiation, and the designed FPA microspheres were employed as Fenton-like catalysts to degrade micropollutants. Results showed that UV irradiation could activate the generation of the polydopamine shell and accelerate the Ag deposition, which played a crucial role in the rapid synthesis of highly active and stable FPA catalysts. Relative to reported catalysts, these FPA microspheres exhibited outstanding catalytic degradation performance, achieving 94.38% removal of tetracycline within 60 min. This work will provide a convenient strategy in the sustainable and efficient purification of wastewater to improve the quality of human life.

Comparison of consumption behaviors and development needs for the home meal replacement among Chinese college students studying abroad in Korea, Chinese college students in China, and Korean college students in Korea.

BACKGROUND/OBJECTIVES: The consumption of home meal replacement (HMR) is increasing among college students in Korea and China. In particular, Chinese college students studying abroad in Korea (CSK) show changes in their dietary behavior after migration, and HMR consumption for meal substitution is also increasing. This study was conducted to compare the HMR consumption behaviors and HMR development needs of CSK, Chinese college students in China (CSC), and Korean college students in Korea (KSK). SUBJECTS/METHODS: The subjects were 570 college students (180 CSK, 200 CSC, and 190 KSK) who had experience of HMR consumption. Data were collected by face-to-face survey in 2019 and analyzed using SPSS 25.0. RESULTS: The majority of the subjects purchased HMR to 'saving time' and 'preventing meal skipping'. Average purchase price per HMR was about 5,000 won for the CSK and KSK, and about 3,000 won for the CSC. The most important attributes when selecting HMR for the CSK and CSC were hygiene, freshness, and taste in that order, while for the KSK were taste, price, and hygiene. Rice was preferred by the KSK while grilled and fried dishes were preferred by the CSK and CSC. In terms of development needs, dessert and meat-based side dishes were highest in all three groups. The preferred food materials for more than 50% of the subjects of all groups were beef, chicken, pork, shrimp, and squid, and spinach and Chinese cabbage in the CSK, and onion in the KSK. CONCLUSIONS: This study shows more effort is needed to develop the healthy customized HMR for college students studying in Korea and China, and that focuses are placed by CSK on hygiene and freshness, by CSC on meat side dishes, hygiene, and price, and by KSK on snacks (as meal substitutes), taste, and price.

A benzaldehyde-indole fused chromophore-based fluorescent probe for double-response to cyanide and hypochlorite in living cells.

With the rapid development of various industries, cyanide (CN-) and hypochlorite (ClO-) have a tremendously adverse effect on the health of humans and animals. In this study, a fluorescent probe HHTB based on a benzaldehyde-indole fused chromophore was designed to detect cyanide and hypochlorite simultaneously. The synthesized probe was found to have strong anti-interference ability. In addition, the designed probe could respond rapidly to ClO- in just 80 s, while the color changed visibly from red to colorless. Moreover, the response time to CN- was longer (about 160 s), with the apparent color change from red to light red. The ratiometric and colorimetric absorbance variation of HHTB was due to the nucleophilic attack of CN- on the indole CN functional group and the strong oxidization of ClO- which destroyed the CC bonds and the conjugation systems. Furthermore, the probe HHTB responding to ClO- and CN- presented high sensitivity, as the calculated detection limits were 1.18 nM and 1.40 nM, respectively. The probe was also found to have low biological toxicity and was used in living cells successfully. Therefore, it has good application prospect in the field of cell imaging and biomedicine. The binding mechanism of HHTB-CN and the reaction mechanism of HHTB and ClO- were further elucidated by a series of experiments.

Fast preparation of Fe3O4@polydopamine/Au for highly efficient degradation of tetracycline.

This work reported the fast synthesis of magnetic polydopamine Au-Fenton catalyst (Fe3O4@PDA/Au) under UV irradiation at 365 nm. The microstructure of prepared nanocomposites was characterized by various techniques. The effects of several key factors (pH values, H2O2 content and TC concentration) of tetracycline (TC) degradation were evaluated. The results revealed that the TC and total organic carbon (TOC) removal rate reached up to 98.16% and 93.14% within 300 min under optimal conditions (pH 3, H2O2 80 µL, TC concentration 20 mg/L). Besides, HO radicals were generated during the Fenton-like degradation process and the plausible degradation mechanism was discussed. Moreover, Fe3O4@PDA/Au catalyst retained excellent catalytic capacity (TC removal rate 96.94% and TOC removal rate 87.69%) and exhibited fantastic stability after six cycles. Moreover, metal ions leaching was evaluated (0.023 mg/L). Altogether, the novel Fe3O4@PDA/Au Fenton-like catalyst is highly promising for wastewater management.

Tetraphenylethylene-vitamin E Conjugates as sensitive aggregation-induced emission probes for selective detection of explosive FOX-7.

With the increasingly severe international security situation, the application of explosives is more and more extensive, and the probes that can detect the explosives quickly and efficiently have attracted people's attention. In this work, two novel probes T1 and T2 were synthesized through vitamin E succinate and tetraphenylethylene derivative. Fluorescence spectra showed that both T1 and T2 had a typical aggregation-induced emission (AIE) effect in THF/H2O solution, and explosive FOX-7 could effectively quench this fluorescence without being affected by other explosives or ions. The filter paper and cotton rods prepared with these two probes could detect FOX-7 specifically, which also provided the possibility for practical application on the battlefield.

A near-infrared fluorescent probe for highly specific and ultrasensitive detection of hypochlorite ions in living cells.

Hypochlorite (ClO-) is an important reactive oxygen species (ROS) in organisms. In this work, a fluorescent probe DBTM based on triphenylamine was synthesized successfully and characterized by spectral methods. The designed probe can rapidly respond to ClO- in just 1 min, followed by the apparent color change from red to yellow. The colorimetric and ratiometric absorbance change of DBTM was attributed to the strong oxidation of ClO-, which broke the connected double bonds and destroyed the conjugate system. The probe DBTM showed an excellent selectivity towards ClO- in comparison with other ROS probes. Besides, the DBTM probe exhibited a highly sensitive response to ClO-, with the detection limits calculated to be 3.3 nM. The probe can be applied in the form of cotton swabs and test strips that could detect ClO- easily, suggesting its potential use as imaging agents for realistic ClO- detection. In particular, DBTM exhibited very low background fluorescence in living cells and was able to detect the minor variation of endogenous hypochlorite in L929 cells. Based on these advantages, the probe DBTM could be a good candidate for detecting ClO- in biological systems.

Benzimidazole-based turn-on fluorescence probe developed for highly specific and ultrasensitive detection of hypochlorite ions in living cells.

Hypochlorite (ClO- ), as one of the active oxygen species (ROS), plays an essential role in the cellular defence system and organism immunity. In this paper, we successfully synthesized a new 'turn-on' fluorescent probe BMF based on benzimidazole and characterized it by spectroscopic methods. The designed probe can quickly respond to ClO- with the obvious colour change from pink to colourless. Notably, the probe BMF exhibited almost no fluorescence, but showed strong fluorescence after adding ClO- , including an excellent fluorescence turn-on effect. The fluorescence turn-on phenomenon of BMF was attributed to the strong oxidation of ClO- , which severed the connecting double bond and disrupted the intramolecular charge transfer (ICT) system, plus light-induced electron transfer effect between the fluorophore and the recognition group was discontinued. In addition, the cytotoxicity assay showed that the probe had lower cytotoxicity. Based on these advantages, we demonstrated that probe BMF might be a good candidate for detecting ClO- in biological systems.

Highly efficient removal of antibiotic from biomedical wastewater using Fenton-like catalyst magnetic pullulan hydrogels.

Magnetic nanoparticles that can be employed as Fenton-like catalysts Fenton-like catalysts are attractive materials for degrading antibiotics. In this study, we facilely prepared novel magnetic pullulan (MP) hydrogels by doping modified magnetic nanoparticles into pullulan matrices, which could enhance catalytic degradation performance and strengthen the stability of resulting hydrogels. This is the first time that MP hydrogels have been fabricated successfully and used as Fenton-like catalysts for tetracycline hydrochloride (TCH) degradation. MP hydrogels were characterized and their catalytic TCH degradation abilities were also investigated. The optimized conditions (pH value, Fe3O4 content, H2O2 content and TCH concentration) for TCH degradation were investigated. The optimized system showed excellent degradation efficiency for TCH. Further, the degradation mechanism was comprehensively studied. Finally, synthesized MP hydrogels showed impressive reusability and stability in the cycle experiment. Thus, our findings would open new possibilities to develop magnetic hydrogels in eliminating antibiotic contaminants.

Two highly sensitive fluorescent probes based on cinnamaldehyde with large Stokes shift for sensing of HSO3- in pure water and living cells.

Two simple and novel fluorescent probes (CDC1 and CDC2) have been designed and prepared here for sensing HSO3- with large Stokes shifts (about 250 nm). The synthesized probes can react with HSO3- just in 2 min, followed by the obvious color change from blue to colorless. The colorimetric and ratiometric absorbance response of the probes to HSO3- is due to the addition of HSO3- to the electron-deficient C=C double bond group, which prevents significant intramolecular charge transfer (ICT). Besides, CDC1 and CDC2 can detect HSO3- in pure water and detection limits of CDC1 and CDC2 reached 4.59 nM and 8.19 nM, respectively. Considering the delicate difference in the two prepared probes' molecular structures, CDC1 containing the carboxyl group has a more significant fluorescence intensity change response to HSO3- in pure water than CDC2 (with sulfinyl group). Beyond better response characteristics, CDC1 also has lower cytotoxicity and better biocompatibility compared with CDC2, which could be chosen to detect HSO3- in living cells. With these superior properties, probe CDC1 could have a potential application in the fields of environmental and biological detection.

A coumarin-connected carboxylic indolinium sensor for cyanide detection in absolute aqueous medium and its application in biological cell imaging.

Fluorescent sensor has been noticed in detecting system due to its sensitive, selective, operational simplicity and low cost. We designed a coumarin-connected carboxylic indolium sensor molecule that is water-soluble and cytomembrane-permeable. This infrared (IR) emitter is selectively sensitive towards cyanide detection in aqueous media according to CN- nucleophilic attack on the indole C=N function. Upon the addition of CN- anion, the color of sensor in water varied from blue to colorless by naked eyes and fluorescence quenching was observed by spectroscopic method. This was because the intramolecular charge transfer (ICT) effect occurred when the fluorescent sensor was added with CN-. The minimum detection limit of the sensor's fluorescence response to CN- is 4.44 × 10-7 mol/L. Furthermore, the cytotoxicity test shows the sensor has lower cytotoxicity, and indicates that this sensor can be utilized for practical detection of trace cyanide in wastewater.

Naphthalene-benzoindole derived two novel fluorometric pH-Responsive probes for environmental systems and bioimaging.

In this work, we designed a kind of novel fluorescent probes based on naphthalene-benzoindole conjugate derived for sensitively monitoring the pH fluctuation in environment and biological systems. In the spectral method, these two probes both show significant red shift, color change and fluorescence quenching due to the effect of intramolecular charge transfer (ICT) mechanism. Moreover, we found that the probe bearing with carboxyl group displayed a more hydrophilicity than the one bearing with hydrogen atom instead, and the former exhibits a faster response and higher fluorescence intensity. Besides, the probe bearing with carboxyl group shows lower cytotoxicity, evidences by the vitro study. It indicates that this probe has great potential in application in living cell imaging as well as pH-fluctuation monitoring.