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关键词： Hypocretin-1   Liquid chromatography-mass spectrometry   Narcolepsy   Orexin-A  

摘要： Hypocretin-1/Orexin-A is associated with stabilization of the sleep/wake cycle. Reductions of cerebrospinal fluid (CSF) concentrations of orexin-A, as determined by radioimmunoassay (RIA), are considered consistent with the diagnosis of narcolepsy type 1 (NT1). However, measuring full-length orexin-A by other methods such as liquid chromatography-tandem mass spectrometry (LC-MS/MS) has proven technically challenging. In this investigation, abundant fragments of orexin-A in CSF were identified and quantified using LC-MS, which allowed assessment of the concordance with clinical RIA measurements.

关键词： Alternating polarity   Cross-coupling   Redox catalysis   Metal free   Electrosynthesis  

摘要： In this work, an electrosynthetic cross-coupling reaction is presented between the carbonyl group of N-(aryl) phthalimides and benzyl/allyl bromides that produces 3-alkyl, 3-hydroxy isoindolin-1-ones. The reaction proceeds via homogeneous reductive catalytic activation of the bromo-compound using N-(aryl)phthalimides as mediators and rapid alternating polarity (rAP) electrolysis;the latter technique permits a more efficient use of the alkyl halide. It is detailed how the reaction was optimized, while citing general trends observed when working with rAP. Voltammetric exploration shows that bromide ion release from the catalytic coupling feeds the counter-electrode reaction, protecting the product from decomposition. These conditions may be extrapolated to carbonyls in general to produce tertiary alcohols as well. Finally, exploration of the reaction scope enabled us to apply the developed reaction to the synthesis of 18 examples of 3-alkyl, 3-hydroxy isoindolin-1-one derivatives and other tertiary alcohols in moderate to good yields at room temperature using carbon-based electrodes, without sub-zero temperatures, metals or unstable reagents.

关键词： Gly-Gln   Ischemia-reperfusion   Neuroprotection   Sigma-1 receptors  

摘要： Cerebral ischemia-reperfusion injury is characterized by oxidative stress, inflammation, and apoptotic cell death, which results in tissue damage. Although the Glycyl-Glutamine (Gly-Gln) dipeptide has primarily been investigated as a glutamine donor, its direct pharmacological effects and underlying mechanisms remain poorly defined.

关键词： 瞬时受体电位锚蛋白1   中医药   疾病治疗   研究进展  

摘要： 瞬时受体电位(transient receptor potential,TRP)通道中的瞬时受体电位锚蛋白1(transient receptor potential ankyrin 1,TRPA1)通道广泛分布于多种类型细胞中,可介导多种疾病的发生,在中医药研究中具有重要的潜在价值,因此总结近年来TRPA1通道在中医药领域的研究概况。TRPA1通道参与了中药对多种疾病的治疗作用,主要包括以下几类:与疼痛相关的疾病,如神经病理性疼痛、内脏痛、肠易激综合征、肠道炎症、慢性胰腺炎、偏头痛和糖尿病神经病变等;与“寒邪”相关的疾病,如膝骨关节炎和哮喘等;以及其他多种疾病,如咳嗽、心血管疾病、胃癌和特异性皮炎等。研究还发现,许多中药方剂对TRPA1通路具有调节作用,例如黄芪桂枝五物汤、当归四逆汤、吴茱萸汤及理中丸等。TRPA1通道不仅有助于揭示疾病的病理机制,也为中药方剂作用机制的研究提供了新的途径。随着未来研究的不断深入,TRP家族有望为中药治疗疾病的作用机制提供新的研究思路,揭示中药的作用机制及更高效的治疗通路。

关键词： Trace moisture   Spectral analysis   Line intensity  

摘要： The absorption spectra of H${}_2$O in Ar gas with a mole fraction of 500 nmol/mol were obtained near 7181 cm⁻¹. A reference gas (water vapor in Ar gas) was generated using a multi-gas trace-moisture generator (Multi-TMG), previously developed as a generation system of primary trace-moisture standards for multiple gas species. The values of the line-shape parameters and line intensity were determined with traceability to the International System of Units (SI) and were compared with previously reported values. The ratios of absorption coefficients of H${}_2$O in Ar and N${}_2$ gases near 7181 cm⁻¹ containing the same amount of water vapor were also evaluated. These results provide important information for trace-moisture measurements in which the moisture concentration is determined only from the absorption coefficient at a specific frequency. Using the evaluated ratios, the measured values obtained in Ar gas can be converted to the correct moisture concentrations, enabling reliable trace-moisture measurements in Ar gas using a moisture analyzer calibrated only in N${}_2$ gas.

关键词： 1,3-Diketo   Jigsaw puzzle method   Mechano-chemistry   Radical  

摘要： Antiwear additives without S and P are often misinterpreted: their antifriction and antiwear effects are frequently attributed to adsorption, overlooking the role of mechanochemistry. A pertinent example is 1,3-diketo compounds, which have been reported to achieve macroscopic superlubricity since 2013, with their lubricity traditionally explained by chelation-driven adsorption on metal surfaces. In contrast, we demonstrate that radical-mediated mechanochemistry is the primary mechanism. Specifically, the keto tautomer of 1,3-diketo compounds serves as a radical initiator, while the enol tautomer functions as a monomer. Under friction, homolysis weak C–C bond in the keto tautomer generates radicals, which initiate polymerization at the CC double bonds of the enol tautomer, ultimately forming a protective tribofilm that reduces friction and wear. This interpretation is based on our “jigsaw puzzle method”, that molecules connected by two stabilized radicals can exhibit mechano-chemical activity. Guided by this mechanism, we designed a compounded system comprising a keto-tautomer-only 1,3-diketo molecule and the double-bond-containing molecule oleic acid. This formulation exhibits antiwear performance about two orders of magnitude better than that of commercial formulated oils. This work calls for broader investigation beyond adsorption, especially on mechano-chemistry, when studying lubrication mechanisms.

关键词： Hilsa shad   Fish migration   Osmoregulation   Gene expression   Na-K-Cl cotransporter  

摘要： The Hilsa Shad is an anadromous fish of major ecological and economic importance in Bangladesh. It migrates between marine and freshwater environments and faces substantial osmotic challenges. There is limited research on osmoregulatory gene expression during migration across diverse habitats. This study provides the first genome-wide identification of the Slc12a2 gene in Hilsa Shad and confirms the existence of two Slc12a2 gene paralogs. To evaluate their potential role in salinity adaptation, we further examined their expression across contrasting habitats. The Bay of Bengal where the fish originates, the genome-wide expression of Slc12a2 has not yet been investigated. The Surma River has been identified as a significant freshwater habitat for Hilsa Shad. However, the molecular information including gene expression data has not yet been reported for this population. In this study, RT-qPCR was used to analyze gill, kidney, liver, and muscle tissues of Hilsa Shad. The results showed that both Slc12a2 paralogs were significantly down-regulated during upstream migration from the Bay to Bengal to the Surma River. These findings demonstrate the essential role of Slc12a2 in maintaining osmotic balance during habitat transition. This genome-wide approach also gives an overall picture of how multiple Slc12a2 gene copies respond to environmental salinity changes and regulate homeostasis.

关键词： Type 1 diabetes   Continuous glucose monitoring   Automated insulin delivery   Device uptake  

摘要：

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  Effective diabetes device onboarding requires support and education.
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  Adults with type 1 diabetes benefit from support for device decision-making.
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  As-needed support in the first three months of uptake can promote durable adoption.

关键词： 1,3-Benzoxazin-4-one   Flash vacuum pyrolysis   Diels-Alder reaction  

摘要： Gas phase thermal elimination of ethanol from 2-ethoxy-2,3-dihydro-1,3-benzoxazin-4-one 2 leads to formation of 1,3-benzoxazin-4-one 3 allowing its characterisation by ¹H and ¹³C NMR for the first time. The compound is highly moisture sensitive and its hydrolysis product, N-formylsalicylamide 8, shows an interesting and complex pattern of hydrogen bonding in the X-ray crystal structure. Reaction with other nucleophiles such as amines leads to ring-opened N-acylformamidines. The compound undergoes BF₃•Et₂O catalysed Diels-Alder reaction with electron-rich dienes such as 2,3-dimethylbutadiene, cyclohexa-1,3-diene, penta-1,3-diene and 2-methylbuta-1,3-diene in CH₂Cl₂ to give a low yield of cycloadducts which were fully characterised by NMR. The same products may also be obtained, in agreement with an earlier study, by reaction of the 2-ethoxy precursor 2 with BF₃•Et₂O in diethyl ether in the presence of 1,3-dienes. In the case of 2-methyl-1,3-butadiene the product of an ene reaction was also observed.

关键词： Nonlinear optics   Organic single crystal   Thermal analysis   Third-order susceptibility   DFT studies  

摘要：

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  A novel DEST single crystal was synthesized via Knoevenagel- metathesis and grown by slow evaporation technique.
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  High laser damage threshold vs DAST l and third-order nonlinear optical susceptibility (χ⁽³⁾) studied by the Z-scan method.
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  Theoretical characterization of DEST was performed using B3LYP/6–31 + G(d,p) model chemistry to study its properties.
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  Molecular vibration, Dipole, NLO properties, FMO analysis and GCRD have been investigated using DFT probe.