Hierarchical Assembly of Flexible Biopolymer Polyphosphate-Manganese into Nanosheets.

Polyphosphate (polyP) is one of the most compact inorganic polyanionic biopolymers that participates in various physiological processes. However, the development of polyP-based nanomaterials is still in its infancy. Here, biocompatible polyphosphate-manganese nanosheets are designed and synthesized by a hierarchical assembly strategy. The thickness and the lateral size of the resulting polyP-Mn nanosheets (PMNSs) are 5 nm and 120-130 nm, respectively. Molecular dynamics simulations suggested that the polyP-hexadecyl trimethyl ammonium bromide flat structure possesses a strong aggregating capacity and serves as the template for the 2D assembly of polyP-Mn. The PMNSs can activate the inflammatory response of macrophages resulting in the recovery of innate immunological functions to inhibit tumor proliferation. This work has initiated a new direction in constructing layered polyP-based nanomaterials and provides guidance for biocompatible and biodegradable biopolymer-based materials in the regulation of innate responses.

Coordination Polymers with 2,2':6',2″-Terpyridine Earth-Abundant Metal Complex Units for Selective CO2 Photoreduction.

Combining molecular metal complexes into coordination polymers (CPs) is an effective strategy for developing photocatalysts for CO2 reduction; however, most such reported catalysts are noble metal-containing CPs. Herein, two novel Zr-containing bimetallic CPs, Co-Zr and Ni-Zr, were designed and successfully synthesized by connecting 2,2':6',2″-terpyridine-based molecular earth-abundant metal (Co or Ni) complexes with ZrO8 nodes. Both CPs were applied as catalysts for CO2 photoreduction to selectively produce CO. The catalytic performance of Co-Zr is better than that of Ni-Zr with a yield of 3654 µmol (g of catalyst)-1 for CO in 6 h (TON = 18.2). The difference between these two catalysts was analyzed with respect to band structure and charge migration ability. This work provides an effective way to introduce molecular earth-abundant metal complexes into coordination polymers for the construction of efficient noble metal-free CO2 photocatalysts.

Direct Electrochemical Selenylation/Cyclization of Alkenes: Access to Functionalized Benzheterocycles.

A catalyst-free, environmentally friendly, and efficient electrochemical selenylation/cyclization of alkenes has been developed with moderate to excellent yields. This selenylated transformation proceeds smoothly and tolerates a wide range of synthetically useful groups to deliver diverse functionalized benzheterocycles, including iminoisobenzofuran, lactones, oxindoles, and quinolinones. Moreover, the present synthetic route could also be readily scaled up to gram quantity with convenient operation in an undivided cell.

Electrochemical regioselective C-H selenylation of 2H-indazole derivatives.

Selenium-substituted heteroarenes are biologically active compounds and useful building blocks. In this study, we have developed a metal- and oxidant-free, environmentally friendly protocol for the regioselective selenylation of 2H-indazole derivatives by an electrochemical strategy. A number of selenylated 2H-indazoles with a wide range of functional groups have been synthesized in moderate to good yields under mild and environment-friendly reaction conditions.

A Comparative Proteomic Analysis of the Buds and the Young Expanding Leaves of the Tea Plant (Camellia sinensis L.).

Tea (Camellia sinensis L.) is a perennial woody plant that is widely cultivated to produce a popular non-alcoholic beverage; this beverage has received much attention due to its pleasant flavor and bioactive ingredients, particularly several important secondary metabolites. Due to the significant changes in the metabolite contents of the buds and the young expanding leaves of tea plants, high-performance liquid chromatography (HPLC) analysis and isobaric tags for relative and absolute quantitation (iTRAQ) analysis were performed. A total of 233 differentially expressed proteins were identified. Among these, 116 proteins were up-regulated and 117 proteins were down-regulated in the young expanding leaves compared with the buds. A large array of diverse functions was revealed, including roles in energy and carbohydrate metabolism, secondary metabolite metabolism, nucleic acid and protein metabolism, and photosynthesis- and defense-related processes. These results suggest that polyphenol biosynthesis- and photosynthesis-related proteins regulate the secondary metabolite content of tea plants. The energy and antioxidant metabolism-related proteins may promote tea leaf development. However, reverse transcription quantitative real-time PCR (RT-qPCR) showed that the protein expression levels were not well correlated with the gene expression levels. These findings improve our understanding of the molecular mechanism of the changes in the metabolite content of the buds and the young expanding leaves of tea plants.

Construction and Biological Evaluation of Different Nanoshell Thickness Ni@SiO2 Nanotubes as Good Protein Separation Carriers for Bovine Hemoglobin.

BACKGROUND: Nickel nanomaterials play an important role in biological applications, but they have high toxicity and poor biocompatibility. To overcome these defects, we coated the surface of Ni nanotubes with different thicknesses of SiO2 to reduce cytotoxicity, improve biocompatibility, and broaden their biological application value. OBJECTIVE: This study aimed to construct Ni nanotubes with different thicknesses of SiO2 nanoshells; investigate the effects of silicon layer thickness, incubation time, and cell line category on the cytotoxicity of the as-synthesized materials, and evaluate the biocompatibility of the materials by biological enzymes. The Ni@SiO2-NH2 was selected for use as an adsorbent for the adsorption and purification of histidine-rich proteins, such as Bovine Hemoglobin (BHb). METHODS: Magnetic Ni nanotubes were prepared by the template-chemical deposition method. A modified version of the Stöber process was used for the SiO2 coating of Ni@SiO2 nanotubes, and adjusted by changing the volume of TEOS for different thicknesses of SiO2 nanoshells. RESULTS: Different cell lines containing tumor cells and normal cells were used in the toxicity experiment, which confirmed the low cytotoxicity and good biocompatibility of Ni@SiO2. To achieve high efficiency of immobilization and purification of histidine- rich proteins, Ni@SiO2-NH2 was obtained by introducing the amino functional group. The Ni@SiO2-NH2 was found to possess lower cytotoxicity and higher adsorption capacity compared to other synthesized materials. Besides, the Ni@SiO2-NH2 also exhibited good selectivity of histidine-rich proteins. CONCLUSION: This work has not only provided ideas for reducing the cytotoxicity and improving the biocompatibility of biological nanomaterials, but also laid a foundation for subsequent biological applications.

A nomogram for predicting the risk of intra-abdominal hypertension in critically ill patients based on ultrasound and clinical data.

Background: Intra-abdominal hypertension (IAH) is a common complication in critically ill patients. This study aimed to identify independent risk factors for IAH and generate a nomogram to distinguish IAH from non-IAH in these patients. Methods: We retrospectively analyzed 89 critically ill patients and divided them into an IAH group [intra-abdominal pressure (IAP) ≥12 mmHg] and a non-IAH group (IAP <12 mmHg) based on the IAP measured from their bladders. Ultrasound and clinical data were also measured. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for IAH. The correlation between IAP and independent risk factors was also assessed. Results: Of these 89 patients, 45 (51%) were diagnosed with IAH. Univariate analysis showed there were significant differences in the right renal resistance index (RRRI) of the interlobar artery, the right diaphragm thickening rate (RDTR), and lactic acid (Lac) between IAH and non-IAH groups (P<0.001). Multivariate logistic regression analysis revealed that increasing RRRI, RDTR, and Lactic acid (Lac) were independent risk factors for IAH (P=0.001, P=0.001, and P=0.039, respectively). IAP was significantly correlated with RRRI, RDTR, and Lac (r=0.741, r=-0.774, and r=0.396, respectively; P<0.001). The prediction model based on regression analysis results was expressed as follows: predictive score = -17.274 + 31.125 × RRRI - 29.074 × RDTR + 0.621 × Lac. Meanwhile, the IAH nomogram prediction model was established with an area under the receiver operating characteristic (ROC) curve of 0.956 (95% confidence interval: 0.909-1.000). The nomogram showed good calibration for IAH with the Hosmer-Lemeshow test (P=0.864) and was found to be applicable within a wide threshold probability range, especially that higher than 0.40. Conclusions: The noninvasive nomogram based on ultrasound and clinical data has good diagnostic efficiency and can predict the risk of IAH. This nomogram may provide valuable guidance for clinical interventions to reduce IAH morbidity and mortality in critically ill patients.

Facet-Dependent Photocatalytic Behavior of Fe-soc-MOF for Carbon Dioxide Reduction.

Exposing different facets on metal-organic frameworks (MOFs) is an efficient approach to regulate their photocatalytic performance for CO2 reduction. Herein, Fe-soc-MOFs exposed with different facets were successfully synthesized, and the morphologies of Fe-soc-MOF exposed with eight {111} facets (Fe-soc-O) and that exposed with eight {111} and six {100} crystal facets (Fe-soc-M) are first reported. Fe-soc-MOFs have facet-dependent active sites on their surface and correspondingly different catalytic performance for photocatalytic CO2 reduction. Fe-soc-O has the highest CO production of 1804 µmol g-1 h-1, while the Fe-soc-MOF exposed with six {100} facets (Fe-soc-C) has the best CO selectivity of 94.7%. Density functional theory (DFT) calculations demonstrate that the (111) facet has more favorable thermodynamic potential for CO2 reduction and H2 evolution compared with the (100) one, deriving from its facet-dependent active sites. This work shows that utilizing the facet-engineering strategy to regulate the active sites exposed on the surface of MOFs is feasible. The results display the relation between the facet of MOFs and the photocatalytic behavior for CO2 reduction.

Atomically precise Ni6(SC2H4Ph)12 nanoclusters on graphitic carbon nitride nanosheets for boosting photocatalytic hydrogen evolution.

Much effort has been devoted to improving the photocatalytic capacity of graphitic carbon nitride (g-C3N4). In this paper, we reported the successful synthesis of a hybrid photocatalyst with superb photocatalytic hydrogen production activity through decorating atomically precise Ni6(SC2H4Ph)12 nanoclusters on g-C3N4 nanosheets (labeled as Ni6/g-C3N4) at room temperature. Zeta potential experiments demonstrated that the electrostatic interaction between Ni6 and g-C3N4 led to the formation of Ni6/g-C3N4. The photocatalytic measurements revealed that the 5 %-Ni6/g-C3N4 prepared with the original mass ratio of m(Ni6)/m(g-C3N4) = 1/20 exhibited the strongest hydrogen production activity. In the system with triethanolamine (TEOA) as the sacrifice agent, the visible-light hydrogen production rate reached up to 5.87 mmol h-1 g-1, approximately 290 times higher than that of pure g-C3N4 (0.02 mmol h-1 g-1). Density functional theory (DFT) calculations testified that the above significant enhancement of photocatalytic hydrogen evolution of the hybrid photocatalyst arose from the photogenerated electrons transfer from Ni6 to g-C3N4.

Reveal the relationship between the quality and the cuticle composition of Satsuma mandarin (Citrus unshiu) by postharvest heat treatment.

To investigate the influence of heat treatment (HT) on Satsuma mandarin fruit's postharvest quality and cuticle composition, we immersed the fruit for 3 min in hot water at 52°C and subsequently stored them at room temperature (25°C) for 28 days, and fruit quality parameters, such as good fruit rate, weight loss rate, firmness, total soluble solids, total titratable acidity, and ascorbic acid content, were monitored. Additionally, changes in the peel's cuticle composition were analyzed, and wax crystal morphologies on the fruit surface were examined using scanning electron microscopy (SEM). The findings revealed that appropriate HT effectively preserved fruit quality. The main compositions of wax and cutin on the fruit's surface remained consistent between the HT and the CK during storage. The total content of wax and cutin initially increased, peaking on the 14th day of storage, and then decreased, falling below the levels observed on day 0. Notably, the total amount of cutin in the HT group exceeded that of the control group. Specifically, ω-hydroxy fatty acids with mid-chain oxo groups and mid-oh-ω-hydroxy fatty acids constituted approximately 90% of the total cutin content. Moreover, the HT group exhibited higher (p < 0.05) total wax content in relation to the control. Fatty acids and alkanes were the predominant components, accounting for approximately 87.5% of the total wax. SEM analysis demonstrated that HT caused wax crystals to melt and redistribute, effectively filling wax gaps. It suggests that HT holds promising potential as a green, safe, and eco-friendly commercial treatment for preserving the postharvest quality of Satsuma mandarin. PRACTICAL APPLICATION: In this study, Satsuma citrus (Citrus unshiu) underwent heat treatment (HT) and was subsequently preserved at room temperature (25°C) for 28 days. The findings revealed that HT significantly improved fruit quality compared to the control group. These findings provide valuable insights into the advancement of eco-friendly and pollution-free citrus preservation methods, offering essential strategies and process parameters for their practical application.

Ti(IV)-MOF with Specific Facet-Ag Nanoparticle Composites for Enhancing the Photocatalytic Activity and Selectivity of CO2 Reduction.

Metal nanoparticles deposited in the photocatalyst not only can serve as a cocatalyst but also can act as a light harvester to extend the light absorption, resulting from the surface plasmon resonance (SPR). In this study, we deposited silver nanoparticles (Ag NPs) onto NH2-MIL-125(Ti) with exposed specific facets and achieved effectively improved activity and selectivity for photocatalytic CO2 reduction. Loading Ag NPs on the exposed {111} facets of NH2-MIL-125(Ti) generates a highly effective composite catalyst for the photoreduction of CO2, resulting in the maximal CO and CH4 yields of 26.7 and 63.3 µmol g-1 h-1, respectively, which are 2.2- and 16.2-fold those of the NH2-MIL-125(Ti) exposing {111} facets, and a CH4 selectivity of 90.5%. Incorporation of Ag NPs not only optimizes the electronic structure of the photocatalyst but also suppresses the recombination of photogenerated electron-hole pairs. This study provides an exciting example for creating and understanding metal-decorated facet-dependent effects on metal-organic frameworks (MOFs) for photocatalytic reactions.

Controlled Atmosphere Improves the Quality, Antioxidant Activity and Phenolic Content of Yellow Peach during the Shelf Life.

Controlled atmosphere (CA) has been demonstrated to maintain the shelf-life quality of fruits, but its effect on the antioxidant activities and phenolic content of yellow peach is not comprehensive. This study analyzed the role of CA on the quality of shelf period, phenolic content and antioxidant activity of "Jinxiu" yellow peach. Yellow peach was left under specific aeration conditions (3.5-4% CO2, 2-3% O2, 92-95.5% N2, 1 ± 0.5 °C) and the control (1 ± 0.5 °C) for 21 d, to observe changes in physiological parameters of the fruit during 10 d of the shelf life (25 ± 1 °C). The result showed that CA reduced the weight loss rate (WLR), decay rate (DR), and browning index (BI) of yellow peaches. Furthermore, the CA held a high level of total flavonoid content (TFC), total phenol content (TPC) and phenolic content in the fruit. Antioxidant analysis showed that polyphenol oxidase (PPO) enzyme activity was lower and free radical scavenging capacity (DPPH, ABTS, and FRAP) and antioxidant enzyme activities (POD and PAL) were higher in the CA group. Combining the results of significance analysis, correlation analysis, principal component analysis (PCA) and hierarchical cluster analysis (HCA) clearly identified the differences between the CA group and the control group. The results showed that the CA could maintain higher phenolic content and reduce the oxidation of yellow peach fruit and enhance fruit quality by affecting the antioxidant activities of yellow peach.

Effect of the Defect Modulator and Ligand Length of Metal-Organic Frameworks on Carbon Dioxide Photoreduction.

The nature of defects and organic ligands can fine-tune the absorption energy (Eabs) of metal-organic frameworks (MOFs), which is crucial for photocatalytic reactions; however, the relevant studies are in their infancy. Herein, a series of typical MOFs of the UiO family (UiO-6x-NH2, x = 8, 7, and 6) with ligands of varied lengths and amino-group-modified defects were synthesized and employed to explore their performance for photocatalytic CO2 reduction. Sample UiO-66-NH2-2ABA (2ABA = 3,5-diamino-benzoate) with the shortest dicarboxylate ligand and two amino-group-modified defects exhibits superior photocatalytic activity due to the lowest Eabs. The CO yield photocatalyzed by UiO-66-NH2-2ABA is 17.5 µmol g-1 h-1, which is 2.4 times that of UiO-68-NH2-BA (BA = benzoate) with the longest ligand and no amino group involved in the defects. Both the experiments and theoretical calculations show that shorter dicarboxylate ligands and more amino groups result in smaller Eabs, which is favorable for photocatalytic reactions. This study provides new insights into boosting the photocatalytic efficiency by modulating the defects and ligands in MOFs.

Simple vapor-solid-reaction route for porous Cu2O nanorods with good HER catalytic activity.

In this work, a simple vapor-solid reaction route was designed for the preparation of porous Cu2O nanorods with good HER catalytic performance, employing Cu(OH)2 nanorods as the precursor and ethylene glycol as the reductant. The reaction was carried out under an Ar atmosphere in the temperature range of 200-280 °C for 2 h. The final product was characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), (high-resolution) transmission electron microscopy (TEM/HRTEM), X-ray photoelectron spectroscopy (XPS), HAADF-STEM-EDS mapping and nitrogen adsorption-desorption isotherms. It was found that pure Cu2O was always obtained in the temperature range of 200-280 °C and well retained the outline of the precursor. Nevertheless, electrochemical experiments showed that porous Cu2O nanorods prepared at 200 °C (labeled as Cu2O-200) exhibited much stronger HER catalytic activity than those obtained at higher temperatures, which were labeled as Cu2O-220, Cu2O-240, Cu2O-260 and Cu2O-280, respectively. In an alkaline solution of 1.0 M KOH, Cu2O-200 presented a low overpotential of ∼184 mV, a small Tafel slope of 106 mV dec-1, and a high durability over 20 h at a current density of 10 mA cm-2. The above good performances were attributed to the high surface area and high-speed electronic transmission networks of Cu2O-200, which provided fast transportation and short diffusion path for the electrolyte and evolved H2 bubbles.

PPAR-γ Ligand Inhibits Nasopharyngeal Carcinoma Cell Proliferation and Metastasis by Regulating E2F2.

PURPOSE: Peroxisome proliferator-activated receptor-γ (PPAR-γ) is a nuclear hormone receptor with a key role in lipid metabolism. Previous studies have identified various roles of PPAR-γ in cell cycle progression, cellular proliferation, and tumor progression. However, no report has described a role for PPAR-γ in human nasopharyngeal carcinoma (NPC). Notably, some studies have reported a relationship between PPAR-γ and E2F transcription factor 2 (E2F2), which has been identified as a regulator of cell cycle, apoptosis, and the DNA damage response. Notably, E2F2 has also been reported to correlate with a poor prognosis in patients with various malignancies. METHODS: We used immunohistochemical (IHC) and western blot methods to evaluate PPAR-γ and E2F2 expression and function in nonkeratinizing NPC and nasopharyngitis (NPG) tissue samples, as well as western blotting and CCK8 analyses in the NPC cell lines, CNE1 and CNE2. RESULTS: We observed lower levels of PPAR-γ expression in nonkeratinizing NPC tissues compared with NPG tissues and determined an association between a low level of PPAR-γ expression with a more advanced tumor stage. Furthermore, strong E2F2 expression was detected in nonkeratinizing NPC tissues. We further demonstrated that rosiglitazone, a PPAR-γ agonist, reduced E2F2 expression and proliferation in NPC cell lines. CONCLUSIONS: Our study results revealed a novel role for the PPAR-γ-E2F2 pathway in controlling NPC cell proliferation and metastasis.

A titanium-based photo-Fenton bifunctional catalyst of mp-MXene/TiO2-x nanodots for dramatic enhancement of catalytic efficiency in advanced oxidation processes.

mp-MXene/TiO2-x nanodots (NDs) structurally composed of microporous MXene monolayers embedded with Ti3+-doped TiO2 nanodots were developed for the first time. The drastically enhanced catalytic efficiency (as much as 13 times higher than that of P25) in degrading dye molecules over mp-MXene/TiO2-x NDs is due to a synergistic effect of the pseudo-Fenton reaction and photocatalysis.

Photocatalytic Degradation of 4-Nitrophenol by C, N-TiO2: Degradation Efficiency vs. Embryonic Toxicity of the Resulting Compounds.

The photocatalytic activity of TiO2 based photocatalysts can be improved by structural modification and elemental doping. In this study, through rational design, one type of carbon and nitrogen co-doped TiO2 (C, N-TiO2) photocatalyst with mesoporous structure was synthesized with improved photocatalytic activity in degrading 4-nitrophenol under simulated sunlight irradiation. The photocatalytic degradation efficiency of the C, N-TiO2 was much higher than the anatase TiO2 (A-TiO2) based on absorbance and HPLC analyses. Moreover, using zebrafish embryos, we showed that the intermediate degradation compounds generated by photocatalytic degradation of 4-nitrophenol had higher toxicity than the parent compound. A repeated degradation process was necessary to render complete degradation and non-toxicity to the zebrafish embryos. Our results demonstrated the importance of evaluating the photocatalytic degradation efficiency in conjunction with the toxicity assessment of the degradation compounds.