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Abstract: Highly transparent Tm3Al5O12 (TmAG) ceramics were fabricated by solid-state reaction and vacuum sintering. Densification, microstructure evolution, mechanical, thermal, and optical properties of the TmAG ceramics were investigated. Fully dense TmAG ceramic with average grain size of ∼15μm was obtained by sintering at 1780°C for 20h. The in-line transmittance was 80.5% at 2000nm. The absorption coefficients at 682nm and 785nm were 8.03cm−1 and 8.33cm−1, respectively. The Vickers hardness, the Young modulus, the bending strength, and the fracture toughness values were 15.14GPa, 343GPa, 230MPa, and 2.35MPam1/2, respectively. The thermal conductivity at room temperature was 3.3W/mK and the average linear thermal expansion coefficient from 20°C to 1000°C was 8.915×10−6 K. [Copyright &y& Elsevier]

A total synthesis strategy was developed for the synthesis of luotonin A, B and their analogues using synergistic FeCl3/KI‐catalyzed oxidative cyclization. This protocol utilizes cheap and widely available N‐propargyl 2‐methyl‐quinazolinones and arylamines under mild conditions, and it has a wide substrate scope and high atom economy. Different natural products (luotonin A, B and derivatives) can be synthesized via a unique switchable approach. Further transformations from luotonin B to luotonin E and structural modification of natural products demonstrate the potential applications of this method. Moreover, camptothecin can also be modified with the reported protocol to afford the hydroxyl‐substituted product. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is one of the most common malignant tumors of the digestive system, ranking third for morbidity and mortality worldwide. At present, no effective control method is available for this cancer type. In tumor cells, especially iron metabolization, is necessary for its growth and proliferation. High levels of iron are an important feature to maintain tumor growth; however, the overall mechanism remains unclear. Methods: We used western blotting, immunohistochemistry (IHC) and real-time quantitative PCR to analyze the expression of IGF2BP2 in cell lines and tissues. Further, RNA-sequencing, RNA immunoprecipitation and methylated RNA immunoprecipitation experiments explored the specific binding of target genes. Moreover, the RNA stability assay was performed to determine the half-life of genes downstream of IGF2BP2. In addition, the Cell Counting Kit-8, colony formation assay, 5-ethynyl-2'-deoxyuridine assay and flow cytometry were used to evaluate the effects of IGF2BP2 on proliferation and iron metabolism. Lastly, the role of IGF2BP2 in promoting CRC growth was demonstrated in animal models. Results: We observed that IGF2BP2 is associated with iron homeostasis and that TFRC is a downstream target of IGF2BP2. Further, overexpression of TFRC can rescue the growth of IGF2BP2-knockdown CRC cells. Mechanistically, we determined that IGF2BP2 regulates TFRC methylation via METTL4, thereby regulating iron metabolism and promoting CRC growth. Furthermore, using animal models, we observed that IGF2BP2 promotes CRC growth. Conclusion: IGF2BP2 regulates TFRC mRNA methylation via METTL4, thereby regulating iron metabolism and promoting CRC growth. Our study highlights the key roles of IGF2BP2 in CRC carcinogenesis and the iron transport pathways. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Chlorella sp. CN6 with high macular pigment (MP) production was isolated. • A four-stage continuous microalgal culture module was established for MP production. • MP concentration of CN6 through white light and blue LED irradiation was 8.16 g/L. • MP productivity in the continuous culture module was 7.28 mg/L/day for 10 days. • The MP recovery and purity were > 80 % and > 90 %, with a lutein: zeaxanthin of 4–5:1. This study established and investigated continuous macular pigment (MP) production with a lutein (L):zeaxanthin (Z) ratio of 4–5:1 by an MP-rich Chlorella sp. CN6 mutant strain in a continuous microalgal culture module. Chlorella sp. CN6 was cultured in a four-stage module for 10 days. The microalgal culture volume increased to 200 L in the first stage (6 days). Biomass productivity increased to 0.931 g/L/day with continuous indoor white light irradiation during the second stage (3 days). MP content effectively increased to 8.29 mg/g upon continuous, indoor white light and blue light-emitting diode irradiation in the third stage (1 day), and the microalgal biomass and MP concentrations were 8.88 g/L and 73.6 mg/L in the fourth stage, respectively. Using a two-step MP extraction process, 80 % of the MP was recovered with a high purity of 93 %, and its L:Z ratio was 4–5:1. [ABSTRACT FROM AUTHOR]

• MPC can set and harden normally at ≥−10 °C due to the double hydrolysis role of monoammonium phosphate and borax. • The reaction degree of MPC at room temperature ls lower than that at 0 °C. • The 2-hour compressive strength of the MPC (M/P = 4, B/M = 0.03 and W/C = 0.14) exceeds 15.0 MPa at −10 ± 2 °C. • The frozen MPC specimens were placed in room temperature, its compressive strength continues to increase due to the secondary reaction of MPC. Magnesia-phosphate cement (MPC) is considered the most promising inorganic cementing material for the rush-repair construction of concrete structures, pavements, and airport runways in negative-temperature environments. To prepare MPC repair materials that are suitable for negative temperatures, we studied and quantitatively analyzed the influences of dead-burned magnesia/phosphate (M/P), borax/dead-burned magnesia (B/M), and water/MPC (W/C) ratios on the reaction rate, early strength, and long-term strength of MPC prepared and cured at negative temperatures. The ice point of the mixed water decreased to −10 °C because of the double hydrolysis role of monoammonium phosphate and borax; therefore, MPC could set and harden at temperatures higher than −10 °C, and its 2 h compressive strength was > 15 MPa. The setting and reaction rate of MPC decreased steeply with decreasing temperature, and the 2 h compressive strength was as low as 3.0 MPa at − 20 ± 2 °C. The early strength of MPC enhanced on increasing the magnesium ion concentration in the MPC slurry, and the 2 h compressive strength of MPC at − 10 ± 2 °C increased by approximately 50% when the M/P ratio increased from 3 to 5. The early strength of MPC at negative temperatures was more sensitive to changes in the B/M and W/C ratios than at room temperature (20 ± 2 °C). When the temperature of the frozen MPC specimens that were maintained at − 10 ± 2 °C and − 20 ± 2 °C was increased to room temperature, the long-term strength of the MPC increased to approximately 80.9% and 67.6%, respectively, than that of the MPC maintained at room temperature, owing to the secondary reaction in the MPC. [ABSTRACT FROM AUTHOR]

In the present study, we aimed to investigate the effects of puerarin on the hyperpermeability of vascular endothelial cells induced by lipopolysaccharide (LPS) and its underlying mechanisms. Human umbilical vein endothelial cells (HUVECs) were pre-incubated with puerarin (25, 50, and 100 μM) for 1 h, and then exposed to LPS (1 μg/mL). The monolayer permeability of endothelial cells was assessed by measuring the paracellular flux of FITC-dextran 40,000 (FD40). The expression of vascular endothelial cadherin (VE-cadherin) in HUVECs was examined by Western blotting analysis. A total of 18 mice were randomly assigned into three groups as follows: control group, LPS group, and puerarin group. The pulmonary W/D ratio (wet-to-dry weight ratios) was calculated, and the lung morphology was examined. The levels of TNF-α and IL-1β in cell supernatant and mouse serum were determined by ELISA. Compared with the control group, LPS obviously increased the flux of FD40 and the monolayer permeability, raised the levels of TNF-α and IL-1β in cell supernatant, and reduced the VE-cadherin expression in HUVECs. However, puerarin (25, 50, and 100 μM) was able to relieve such LPS-induced increase in flux of FD40 and then reduce the hyperpermeability. Puerarin decreased the levels of TNF-α and IL-1β in cell supernatant and increased the VE-cadherin expression in HUVECs (P < 0.05). Moreover, LPS obviously increased the levels of TNF-α and IL-1β in mouse serum and elevated the pulmonary W/D ratios, resulting in lung injury. However, all of above-mentioned LPS-induced changes were improved by puerarin pre-treatment. Puerarin could alleviate LPS-induced hyperpermeability in endothelial cells via preventing downregulation of endothelial cadherin. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient bagasse biorefinery with low energy consumption was realized. • A thermostable xylanase mutant was engineered for catalysis under mild conditions. • Seawater following steam explosion promotes the enzymatic hydrolyzation of bagasse. • Synergistic hydrolysis of high activity xylanase and cellulase was optimal. Lignocellulosic biorefining for producing biofuels poses technical challenges. It is usually conducted over a long time using heat, making it energy intensive. In this study, we lowered the energy consumption of this process through an optimized enzyme and pretreatment strategy. First, the dominant mutant M137E/N269G of Bispora sp. MEY-1 XYL10C_ΔN was obtained by directed evolution with high catalytic efficiency (970 mL/s∙mg) and specific activity (2090 U/mg) at 37 °C, and thermostability was improved (T 50 increased by 5 °C). After pretreatment with seawater immersion following steam explosion, bagasse was co-treated with cellulase and M137E/N269G under mild conditions (37 °C), the resulting highest yield of fermentable sugars reached 219 µmol/g of bagasse, 46% higher than that of the non-seawater treatment group, with the highest degree of synergy of 2.0. Pretreatment with seawater following steam explosion and synergistic hydrolysis through high activity xylanase and cellulase helped to achieve low energy degradation of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

The red oxide phosphors activated by Mn4+ have become a research hotspot because of their excellent physical/chemical stability, which can be applied in the field of light-emitting diodes (LED) plant growth lighting. Here, a new type of Sr 9 Gd 2 W 4 O 24 (SGWO):Mn4+ red phosphor was prepared by traditional high temperature solid state reaction method. The phase compositions and morphologies of powders were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The luminescent properties of the samples with varying Mn4+ concentrations were investigated, and the photoluminescence excitation (PLE) spectra illustrate that samples can be effectively excited by near-ultraviolet/blue light. Furthermore, typical concentration quenching occurs when the doping concentration of Mn4+ exceeds 0.4 mol%. In addition, the thermal activation energy of the sample was calculated to be 0.3641 eV. Importantly, under the excitation of near-UV light at 365 nm, SGWO:0.004Mn4+ phosphor can emit bright far-red light. All the results indicated that SGWO:Mn4+ phosphors have potential application value in indoor plant cultivation. • Tetratungstate Sr 9 Gd 2 W 4 O 24 :Mn4+ sample was synthesized by high temperature method. • SGWO:Mn4+ phosphor can emit far-red light under the 365 nm NUV excitation. • The PL of SGWO:Mn4+ match well with the absorption spectrum of phytochrome P FR. [ABSTRACT FROM AUTHOR]

Prussian blue (PB) is authenticated in clinical treatment, while it generally exhibits unfavorable chemodynamic therapy (CDT) performance. Herein, we developed manganese-doped prussian blue (PBM) nanoparticles to significantly enhance both CDT and photothermal therapy (PTT) effect. The lower redox potential of Mn 3+/2+ (0.088 V) in PBM against that of Fe 2+/3+ (0.192 V) in PB leads to favorable electron transfer of PBM with respect to PB. Besides, PBM has a lower charge-transfer resistance (Rct) of 2.98 Ω than 4.83 Ω of PB. Once PBM entering the tumor microenvironment (TME), Mn 3+ may be readily reduced by glutathione (GSH) and therein to enhance intracellular oxidative stress. Meanwhile, the superoxide dismutase (SOD)-like activity of PBM facilitates the conversion of endogenous superoxide (O 2 •- ) into H 2 O 2 . Mn 2+ subsequently catalyzes H 2 O 2 to generate toxic hydroxyl radicals (•OH). Notably, the PBM plus laser irradiation can effectively trigger a robust immunogenic cell death (ICD) due to the combination therapy of CDT and PTT. Additionally, the mice treated by PBM followed by laser irradiation efficiently avoided splenomegaly and lung metastasis, along with significant up-regulation of the Stimulator of Interferon Genes (STING) expression. Overall, PBM significantly inhibits tumor growth and metastasis, making it a promising multifunctional nanoplatform for cancer treatment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Timely diagnosis, monitoring, and management of chronic wounds play crucial roles in improving patients' quality of life, but clinical evaluation of chronic wounds is still ambiguous and relies heavily on the experience of clinician, resulting in increased social and financial burden and delay of optimal treatment. During the different stages of the healing process, specific and dynamic changes of pH values in the wound exudate can be used as biomarkers to reflect the wound status. Herein, a pH-responsive agent with well-behaved photoacoustic (PA) properties, nitrazine yellow (NY), was incorporated in poly(vinyl alcohol)/sucrose (PVA/Suc) hydrogel to construct a wearable pH-sensing patch (PVA/Suc/NY hydrogel) for monitoring of pH values during chronic wound healing. According to Rosencwaig-Gersho theory and the combination of 3D printing technology, the PA chamber volume and chopping frequency were systematically optimized to improve the sensitivity of the PA analytical system. The prepared PVA/Suc/NY hydrogel patch had excellent mechanical properties and flexibility and could maintain conformal contact with skin. Moreover, combined with the miniaturized PA analytical device, it had the potential to detect pH values (5.0-9.0) free from the color interference of blood and therapeutic drugs, which provides a valuable strategy for wound pH value monitoring by PA quantitation. This strategy of combining the wearable hydrogel patch with portable PA analysis offers broad new prospects for the treatment and management of chronic wounds due to its features of simple operation, time savings, and anti-interference.

The growing preference for incorporating microbial aspartic proteases in industries is due to their high catalytic function and high degree of substrate selectivity. These properties, however, are attributable to molecular alterations in their structure and a variety of other characteristics. Molecular tools, functional genomics, and genome editing technologies coupled with other biotechnological approaches have aided in improving the potential of industrially important microbial proteases by addressing some of their major limitations, such as: low catalytic efficiency, low conversion rates, low thermostability, and less enzyme yield. However, the native folding within their full domain is dependent on a surrounding structure which challenges their functionality in substrate conversion, mainly due to their mutual interactions in the context of complex systems. Hence, manipulating their structure and controlling their expression systems could potentially produce enzymes with high selectivity and catalytic functions. The proteins produced by microbial aspartic proteases are industrially capable and far-reaching in regulating certain harmful distinctive industrial processes and the benefits of being eco-friendly. This review provides: an update on current trends and gaps in microbial protease biotechnology, exploring the relevant recombinant strategies and molecular technologies widely used in expression platforms for engineering microbial aspartic proteases, as well as their potential industrial and biotechnological applications.

Background: The standardization of quantification data is critical for ensuring the reliability and measurement traceability in the screening of neonatal inherited metabolic disorders. However, the availability of national certified reference materials is limited in China., Methods: In this study, we developed a series of dried blood spot (DBS) reference materials containing 9 amino acids (AA) and 10 acylcarnitines (AC) for neonatal screening. Four levels of the reference materials were measured with tandem mass spectrometry (MS/MS) by seven laboratories using different commercial In Vitro Diagnostic Device (IVD) kits. Then, 100 clinical samples were measured using both derivatization and non-derivatization methods by the same laboratory., Results: We found high homogeneity and stability at all levels of the reference materials, with the coefficient of variation (CV) of the analytes less than 15%. These reference materials can be used to assess the testing capabilities of different laboratories. Our test also revealed that the correction factors (CF) calculated by the reference materials, along with clinical samples, could increase the consistency for different kits., Conclusion: The DBS reference materials proposed in this study provide reliability for the harmonization in multi-center analysis for the screening of neonatal inherited metabolic disorders. And applying our correction method for the screening could improve the data consistency of the DBS samples prepared by different methods., (© 2023 The Authors. Journal of Clinical Laboratory Analysis published by Wiley Periodicals LLC.)

Objective: To evaluate the diagnostic ability and clinical imaging features in maxillofacial soft tissue hypervascular tumours by 64-slice multidetector spiral computed tomography (64-MDCT) contrast-enhanced scanning., Methods: In a retrospective study of 21 cases of hypervascular tumours, the degree of blood supply and indexes were assessed, and the pathological results were used as the diagnostic gold standard to evaluate the sensitivity and specificity of 64-MDCT plain scan and enhanced CT in the diagnosis of oral and maxillofacial soft tissue hypervascular tumours, using the receiver operating characteristic curve to analyse and evaluate the efficacy., Results: Among 21 patients, the diagnostic accuracy of 64-MDCT contrast-enhanced scan was 90.48%, the area under the curve of venous phase CT value was 0.80, the sensitivity was 83.30% and the specificity was 72.73%., Conclusion: 64-MDCT contrast-enhanced scan can be used to evaluate the blood supply of maxillofacial soft tissue hypervascular tumours before an operation. The CT value in the venous phase of tumours has the highest diagnostic effectiveness, which can reduce the risk of blood loss during surgery for maxillofacial hypervascular tumours. In addition, it has certain guiding significance for the formulation of clinical treatment plans.