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An efficient method for the synthesis of indolo[2,1-a]isoquinolines using calcium carbide as an alkyne source, 2-(2-bromophenyl)-1H-indoles as starting materials, and copper as a catalyst is described. The target products are synthesized via Sonogashira cross-coupling/nucleophilic addition tandem reactions. The advantages of this protocol include the use of inexpensive and easy-to-handle solid alkyne source instead of flammable and explosive gaseous acetylene, cheap and readily available raw materials, wide range of substrates, and simple reaction procedure. The method can also be extended to gram scale. In addition, the desired product can also be obtained by one-pot three-component reaction of phenylhydrazine hydrochlorides, o-bromoacetophenones and calcium carbide. [ABSTRACT FROM AUTHOR]

This paper presents a low-distortion and low-power multi-stage noise-shaping (MASH) architecture Sigma-Delta (Σ Δ) modulator with double-sampling. The modulator uses a cascade of integrator feed-forward (CIFF) structure as a cascaded modulator in a MASH architecture. Since the CIFF structure provides a feedforward path from the input signal to the quantizer, the input signal is directly transmitted to the output without loop processing, relaxing the linearity requirement of the modulator, reducing performance requirements for the OTA and harmonic distortion. Double-sampling technique is adopted in the first integrator to double the sampling rate, improving the accuracy of the modulator without the increase of power consumption. In order to eliminate the influence of capacitor mismatch in the sampling network, a fully floating differential switched capacitor (SC) feedback digital-to-analog (DAC) is used in the integrator. The simulation results show that the Σ Δ modulator achieves 113 dB signal-to-noise and distortion ratio (SNDR) and the power consumption is 3.15 mW from a 5 V power supply. [ABSTRACT FROM AUTHOR]

Micro/mini‐light emitting diode (LED) arrays are regarded as the most promising next generation of display devices. However, the inherent Lambertian radiation of LED chips results in a significant pixel crosstalk. To improve the display quality, high‐quality micro/mini‐LED display pixels with fully enclosed composite micro/nano‐packages and in situ nanoimprint technology are proposed and demonstrated in this work. The nanoimprint template is designed as a composite structure comprising an intermediate sandwich cavity array and thin‐bottom nanostructure layer. Contact is maintained between the template and LED chips array substrate. By vacuuming the sealed sandwich cavities, the thin‐bottom nanostructure layer is deformed to drive the upward protrusion of the liquid optical polymer. Moreover, the nanocavities on the thin nanostructure layer are fully filled by the polymer, forming a composite micro/nano‐package. The characteristics of the composite micro/nano‐package, such as the aperture and protrusion height, can be flexibly adjusted by changing the template structure or process parameters. A 6 × 8 array LED chips display device enclosed by a composite micro/nanopackage is developed. The divergence angle of the single LED chip decreases to 72° from the original 138°, the light‐extraction efficiency increases18.4%, and the luminescence spectrum and current‐voltage characteristics changes only minimally. [ABSTRACT FROM AUTHOR]

An efficient method for the construction of 2‐methyl‐1‐sulfonylindoles and 2,3‐dimethyl‐1‐sulfonylindoles using solid calcium carbide as an alkyne source and o‐sulfonamidobenzaldehyde hydrazones or o‐sulfonamidoacetophenone hydrazones as starting materials is described. This protocol has the salient feature of the use of an inexpensive, abundant and easy‐to‐handle solid alkyne source, effectively avoiding the use of flammable and explosive gaseous acetylene as an original alkyne source. Noble‐metal‐free conditions, wide substrate scope, high yield, and simple workup procedures are advantages of this method. The transformation can also be carried out on a gram scale. [ABSTRACT FROM AUTHOR]

Gentamicin (GM) is one of the commonly used antibiotics in the aminoglycoside class but is ototoxic, which constantly impacts the quality of human life. Pyrroloquinoline quinone (PQQ) as a redox cofactor produced by bacteria was found in soil and foods that exert an antioxidant and redox modulator. It is well documented that the PQQ can alleviate inflammatory responses and cytotoxicity. However, our understanding of PQQ in ototoxicity remains unclear. We reported that PQQ could protect against GM‐induced ototoxicity in House Ear Institute‐Organ of Corti 1 (HEI‐OC1) cells in vitro. To evaluate reactive oxygen species (ROS) production and mitochondrial function, ROS and JC‐1 staining, oxygen consumption rate (OCR), and extracellular acidification rate (ECAR) measurements in living cells, mitochondrial dynamics analysis was performed. GM‐mediated damage was performed by reducing the production of ROS and inhibiting mitochondria biogenesis and dynamics. PQQ ameliorated the cellular oxidative stress and recovered mitochondrial membrane potential, facilitating the recovery of mitochondrial biogenesis and dynamics. Our in vitro findings improve our understanding of the GM‐induced ototoxicity with therapeutic implications for PQQ. Gentamicin (GM), a commonly used antibiotic, is often associated with ototoxicity. PQQ exhibits neuroprotective, cardiovascular, and anti‐tumor effects as potent antioxidants. We found that PQQ protected HEI‐OC1 cells in vitro from gentamicin‐induced ototoxicity. Additionally, PQQ enhanced mitochondrial depolarization and reduced ROS levels while preventing the decline of mitochondrial basal respiration and respiratory capacity, thereby improving mitochondrial dynamic impairments. Our in vitro findings enhance our understanding of the ototoxicity caused by genetically modified organisms and have potential therapeutic implications for PQQ. [ABSTRACT FROM AUTHOR]

Background: Esophageal cancer is one of the most common malignant tumors in the world. It is urgent to prevent the development and progression of esophageal cancer. Cancer stem cells (CSCs) were reported to have the ability to initiate tumorigenesis, and reducing the stem cell-like characteristics of tumors is an important strategy to inhibit the occurrence and development of tumors. miRNAs are key regulators of the stemness of cancer. Here, we aimed to investigate the role and regulatory mechanism of miR-191-3p in the stemness properties of esophageal cancer cells., Methods: Esophageal cancer cells with stable expression of miR-191-3p were established by lentivirus system. CCK-8 assay, transwell assay, wound healing assay were used to evaluate the effect of miR-191-3p on proliferation and metastasis of esophageal cancer cells. The expression of stemness-related markers (NANOG, OCT4, SOX2), ALDH activity, sphere-forming assay and subcutaneous tumor model in nude mice were performed to evaluate the stemness properties of esophageal cancer cells in vitro and in vivo. Dual-luciferase reporter assay was used to verify the molecular mechanism., Result: Here we found that overexpression of miR-191-3p promoted the stemness properties of esophageal cancer cells in vitro and in vivo, including increasing esophageal cancer cell proliferation and metastasis ability, the expression of stemness-related markers NANOG, OCT4, and SOX2, ALDH activity, the number of spheres formed and tumor growth. Bioinformatic analysis and dual-luciferase assay demonstrated that regulator of G protein signaling 1 (RGS1) was the directed target gene of miR-191-3p and attenuated the promotion effect of miR-191-3p on the stemness of esophageal cancer cells. Furthermore, we found that RGS1 knockdown activated the PI3K/AKT pathway by negatively regulating CXCR4 to promote the stemness of esophageal cancer cells., Conclusions: Our findings revealed that RGS1 targeted by miR-191-3p inhibited the stemness of esophageal cancer cells by suppressing the CXCR4/PI3K/AKT pathway, which provide potential prognostic markers and therapeutic targets in the future., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Stachyose is a new functional oligosaccharide that exists naturally in plants, including Stachys sieboldii and Rehmannia glutinosa. Because of its low sweetness, low-calorie content, and robust stability, it has been used to improve food quality and develop functional foods. In addition, owing to its targeted regulatory effect on beneficial microorganisms in the gut and its influence on body health, evidence suggests that stachyose's physiological function may be attributed to its interaction with the host. Notably, stachyose's physiological characteristics and functions are largely affected by its extraction process, purity, physical composition, and chemical structure. Therefore, the present review mainly describes the source, extraction, and purification processes, physiological functions, and applications of stachyose in the food processing industry, which would aid in elucidating the biochemical reactions of stachyose in the body, and its future application prospects in the field of food., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts to disclose., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

An efficient method for the construction of 5-arylpyrazolo[1,5- a ]pyrimidines using calcium carbide as a solid alkyne source instead of flammable and explosive gaseous acetylene, pyrazole-3-amine and (hetero)aromatic aldehydes as starting materials in the presence of a copper mediator is described. Meanwhile, 2-arylpyrimido[1,2- b ]indazoles are also synthesized under similar conditions using indazole-3-amine as a substitute for pyrazole-3-amine as a starting material. The method has salient features such as the use of an inexpensive and easy-to-handle alkyne source, commercially available substrates, wide functional group tolerance, a low-cost mediator, and simple workup procedures. This protocol can also be extended to gram-scale synthesis.

Accumulating studies have highlighted the great potential of postbiotics in alleviating diseases and protecting host health. Compared with traditional functional foods (such as probiotics and prebiotics), postbiotics have the advantages of a single composition, high physiological activity, long shelf life, easy absorption, and high targeting, etc. The development of postbiotics has led to a wide range of potential applications in functional food and drug development. However, the lack of clinical trial data, mechanism analyses, safety evaluations, and effective regulatory frameworks has limited the application of postbiotic products. This review describes the definition, classification, sources, and preparation methods of postbiotics, the progress and mechanism of preclinical and clinical research in improving host diseases, and their application in food. Strengthen understanding of the recognition and development of related products to lay a theoretical foundation., Competing Interests: 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., (© 2024 The Author(s).)

Dietary fiber targets the regulation of the intestinal flora and thus affects host health, however, the complex relationship between these factors lacks direct evidence. In this study, the regulatory effects of Konjac glucomannan (KGM) on key metabolites of host intestinal flora were examined by using in vitro fermentation. The results showed that KGM could be utilized by the intestinal flora, which inhibited the relative abundance of Paeniclostridium , Lachnoclostridium , Phascolarctobacterium , and Bacteroides and enriched the relative abundance of Desulfovibrio , Sutterella, etc. Fermentation is accompanied by the production of short-chain acids, including acetic and propionic acids. Metabolomics revealed that KGM significantly promoted amino acid metabolism, lipid metabolism, and the biosynthesis of other secondary metabolites. Correlation analysis results showed that the increase of panose and N-(1-carboxy-3-carboxanilidopropyl) alanylproline content was positively correlated with the relative abundance of Megamonas . These results provide evidence that KGM affects host health by regulating gut microbiota and its metabolites., Competing Interests: None., (© 2024 The Author(s).)