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Chemical resources and techniques have long been used in the history of bulk polyester production and still dominate today's chemical industry. The sustainable development of the polyester industry demands more renewable resources and environmentally benign polyester products. Accordingly, the rapid development of biotechnology has enabled the production of an extensive range of aliphatic and aromatic polyesters from renewable bio-feedstocks. This review addresses the production of representative commercial polyesters (polyhydroxyalkanoates, polylactic acid, poly ε-caprolactone, polybutylene succinate, polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, polyethylene furandicarboxylate, polypropylene furandicarboxylate, and polybutylene furandicarboxylate) or their monomers (lactic acid, succinic acid, 1,4-butanediol, ethylene glycol, terephthalic acid, 1,3-propanediol, and 2,5-furandicarboxylic acid) from renewable bioresources. In addition, this review summarizes advanced biotechniques in the treatment of polyester wastes, representing the near-term trends and future opportunities for waste-to-value recycling and the remediation of polyester wastes under sustainable models. For future prospects, it is essential to further expand: non-food bioresources, optimize bioprocesses and biotechniques in the preparation of bioderived or biodegradable polyesters with promising: material performance, biodegradability, and low production cost. [ABSTRACT FROM AUTHOR]

Matrine, an active component of Sophora flavescens Ait root extracts, has been used in China for years to treat cancer and viral hepatitis. In the present study, we explored the effects of matrine on hyperglycemia-treated cardiomyocytes. Cardiomyocyte function, oxidative stress, cellular viability, and mitochondrial fusion were assessed through immunofluorescence, quantitative real-time PCR (qRT-PCR), enzyme-linked immunosorbent assays, and RNA interference. Matrine treatment suppressed hyperglycemia-induced oxidative stress in cardiomyocytes by upregulating transcription of nuclear factor erythroid 2-like 2 and heme oxygenase-1. Matrine also improved cardiomyocyte contractile and relaxation function during hyperglycemia, and it reduced hyperglycemia-induced cardiomyocyte death by inhibiting mitochondrial apoptosis. Matrine treatment increased the transcription of mitochondrial fusion-related genes and thus attenuated the proportion of fragmented mitochondria in cardiomyocytes. Inhibiting mitochondrial fusion by knocking down mitofusin 2 (Mfn2) abolished the cardioprotective effects of matrine during hyperglycemia. These results demonstrate that matrine could be an effective drug to alleviate hyperglycemia-induced cardiomyocyte damage by activating Mfn2-induced mitochondrial fusion. [ABSTRACT FROM AUTHOR]

Au nanoparticles (AuNPs) (10−15 nm in size) were prepared and deposited on the surfaces of silica particles functionalized using 3-aminopropyltriethoxysilane as the seeds under mild conditions. Then, Au seeds grew further and formed nanosheets by the method of gold chloride hydrate reduction. 3, 5-dimethylphenyl isocyanate derivative of cellulose as chiral selector was coated on the surfaces of SiO2/Au. The obtained spheres possessed a sandwich structure in which silica bead, the packed Au NPs monolayer and cellulose derivative were the core, the interlayer and the shell, respectively. The resultant packing material was evaluated by high-performance liquid chromatography (HPLC) as chiral stationary phase (CSP). The separations of nine pairs of enantiomers were achieved in the normal-phase liquid chromatography mode. The results showed that the new CSP has sufficient interaction with the analytes due to the existence of AuNPs on silica surfaces compared with coated cellulose-silica column. [ABSTRACT FROM AUTHOR]

Near infrared (NIR) spectrum analysis technology has outstanding advantages such as rapid, nondestructive, pollution-free, and is widely used in food, pharmaceutical, petrochemical, agricultural products production and testing industries. Convolutional neural network (CNN) is one of the most successful methods in big data analysis because of its powerful feature extraction and abstraction ability, and it is especially suitable for solving multi-classification problems. CNN-based transfer learning is a machine learning technique, which migrates parameters of trained model to the new one to improve the performance. The transfer learning strategy can speed up the learning efficiency of the model instead of learning from scratch. In view of the difficulty in acquisition of drug NIR spectral data and high labeling cost, this paper proposes three simple but very effective transfer learning methods for multi-manufacturer identification of drugs based on one-dimensional CNN. Compared with the original CNN, the transfer learning method can achieve better classification performance with fewer NIR spectral data, which greatly reduces the dependence on labeled NIR spectral data. At the same time, this paper also compares and discusses three different transfer learning methods, and selects the most suitable transfer learning model for drug NIR spectral data analysis. Compared with the current popular methods, such as SVM, BP, AE and ELM, the proposed method achieves higher classification accuracy and scalability in multi-variety and multi-manufacturer NIR spectrum classification experiments. [ABSTRACT FROM AUTHOR]

The DNA tetrahedron has developed a broad spectrum of applications in biosensor construction thanks to its excellent mechanical rigidity and structural stability. However, how to construct a highly sensitive biosensor using a DNA tetrahedron is still a challenge. In this work, an ultrasensitive electrochemical biosensor based on a DNA tetrahedral nanostructure was developed with the help of synergy from proximity-dependent hybridization. To decrease the steric hindrance of DNA tetrahedra to proximity-dependent hybridization, the detection signal was set on the inclined side chain structure of a DNA tetrahedral sensing system. Additionally, when the target hybridized with the DNA probe, the ferrocene (Fc) labeled on the end of the DNA probe was driven close to the surface of the biosensor, providing a sensitive faradaic current. The experimental results exhibited a good linear relationship from 1 fM to 10 pM with a linear correlation coefficient of 0.9977, and a high sensitivity with a detection limit of 0.2 fM. Our DNA biosensor also showed good stability according to electrode characterization and target detection at different time scales and the anti-jamming capabilities in a complicated biological extraction environment were excellent. The electrochemical sensing system established here has greatly improved the detection sensitivity of a DNA biosensor based on a DNA tetrahedron, which will further promote its practical applications. [ABSTRACT FROM AUTHOR]

A new stationary phase based on β-cyclodextrin and Poly( N-isopropylacrylamide) was prepared. The mass % of the polymer/100 g stationary phase was 23 %. Through investigating the effects of the acetonitrile (ACN) content of the mobile phase, the pH and the column temperature on the retention factor of polar and hydrophilic compounds in the ACN-rich mobile phase, it was found that the new stationary phase had the typical retention behavior of hydrophilic interaction liquid chromatography (HILIC). Moreover, the retention of solutes in the mobile phase exhibited 'U-shaped' curves, which was an indication of HILIC/reversed-phase liquid chromatography (RPLC) mixed-mode retention behavior. In addition, the separation of some hydrophilic and different polar compounds was achieved by using the new material in HILIC and RPLC modes, respectively. [ABSTRACT FROM AUTHOR]

Chronic lymphocytic leukemia (CLL) remains the most incurable leukemia. Early chemotherapeutic treatments, including alkylating agents, purine nucleoside derivatives, and immunotherapeutic antibodies, only show limited benefits for patients but severe off-target related side effects. Recent advances in understanding of the critical molecular pathways of regulating proliferation and survival of B-CLL cells have spurred a new therapeutical strategy by selectively targeting phosphoinositide 3-kinase delta (PI3Kδ). Idelalisib, a first-in-class PI3Kδ-selective small molecule has received the FDA's fast-track approval in July of 2014 as a new treatment of CLL, indolent B-cell non-Hodgkin's lymphoma, and relapsed small lymphocytic lymphoma. Undoubtedly, the success of idelalisib has provided a solid support in the development of PI3Kδ-specific inhibitors and reformed the concept of treating CLL. However, the number of reported selective inhibitors of PI3Kδ is very limited and very few have advanced into clinical trials. The mechanism of their actions remains elusive. More profound understanding on the modes of action of new PI3Kδ inhibitors will further validate the PI3Kδ-targeting strategy, and help to identify biomarkers capable of stratifying patients who will most likely benefit from the therapy. [ABSTRACT FROM AUTHOR]

• A paper-based biosensor to detect hypoxanthine was developed. • The biosensor exhibited microfluidic aggregation effect. • The biosensor produced a linear response of 0.01–0.16 mmolL-1. • The biosensor showed good selectivity and recoveries. • The biosensor could be attached on fish surface to evaluate fish freshness. In this study, a paper-based enzyme biosensor for hypoxanthine (Hx) was developed, enabling visual and one-step fish freshness detection. Xanthine oxidase and horseradish peroxidase were immobilized on nitrocellulose membranes with 3,3′,5,5′-tetramethylbenzidine to output the colour signal. Chitosan oligosaccharide lactate-modified nitrocellulose membranes entrapped the dual-enzyme system and exhibited excellent microfluidic aggregation effect. The developed enzyme biosensor produced a linear response of 0.01–0.16 mmolL-1 with a detection limit of 8.22 μmolL-1, and was selective for Hx with recoveries of 96.13–103.11 % for fish samples. These biosensors were attached directly to the surface of fish samples and the colour was revealed within 3 min. Colour signals can be judged by the naked-eye to distinguish between fresh and spoiled fish samples and analyzed by a smartphone for quantitative analysis. The biosensor shows great potential as a powerful pattern- and reagent-free device for on-site freshness evaluation of fish. [ABSTRACT FROM AUTHOR]

• A direct and visual strand exchange amplification method to detect duck was established. • The method allowed to detect as low as 10 pg/μL duck DNA and 0.1% duck meat in binary mixtures. • The direct SEA could be performed with only a simple heating block and required 1 h to finish. Simple, fast and efficient method for on-site detection of meat adulteration is of increasing demand in low-resource regions. Here, a direct and visual denaturation bubble-mediated strand exchange amplification method (SEA) was developed to detect meat adulteration by targeting the mitochondrial sequence from duck, which required only a heating block. The method allowed detecting as low as 10 pg/μL duck DNA and 0.1% duck meat in binary mixtures, sufficiently meeting the demand of meat adulteration detection. Notably, the method realized instrument-free readout by significant color discrimination of positive and negative results. By coupling with fast DNA release, a direct SEA method was developed and reduced the whole detection time to 1 h, eliminating complex DNA extraction process. The developed method provided a promising strategy with integration of fast sample lysis, miniaturized reaction platform and visual readout for meat adulteration, especially suitable for low resource point-of-care settings. [ABSTRACT FROM AUTHOR]

Background: It is challenging yet critical to differentiate between hemorrhagic transformation (HT) and contrast extravasation on non-contrast-enhanced computed tomography (NCCT) scans following mechanical thrombectomy (MT) in patients with acute ischemic stroke. We propose a new method called the ratio of maximum density values (RMDV) to minimize the confusion of contrast extravasation and to evaluate the diagnostic significance of RMDV in predicting HT on immediate post-interventional NCCT scans., Methods: We conducted a retrospective analysis of the prospective patients' database who received MT for acute ischemic stroke caused by occlusion of the intracranial large artery and showed postinterventional cerebral hyperdensities (PCHDs) on NCCT scans immediately after MT. Based on the subsequent NCCT scans, we divided patients with PCHDs into the HT and the non-HT groups. The clinical characters and radiological details were collected and compared to the two groups. We assessed the ability of RMDV >1 to predict HT by analyzing the receiver operating characteristic curve., Results: One hundred and three patients showed PCHDs; 58 (56.31%) were classified as HT, while 45 (43.69%) were classified as non-HT. The only notable distinction between the two groups was the proportion of RMDV >1 in the HT group. The correlation between HT and RMDV >1 with an area under the curve of 0.826 (95% confidence interval, 0.739 to 0.894). The sensitivity, specificity, positive, and negative predictive values of RMDV >1 on NCCT for predicting HT were 89.66, 75.56, 82.54, and 85.00%, respectively., Conclusion: The utilization of RMDV >1 on immediate NCCT scans after MT can predict early HT with good sensitivity and specificity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Qiao, Zheng, Wei and Zhao.)