A Smart Hyperthermia Nanofiber-Platform-Enabled Sustained Release of Doxorubicin and 17AAG for Synergistic Cancer Therapy

This study demonstrates the rational fabrication of a magnetic composite nanofiber mesh that can achieve mutual synergy of hyperthermia, chemotherapy, and thermo-molecularly targeted therapy for highly potent therapeutic effects. The nanofiber is composed of biodegradable poly(ε-caprolactone) with doxorubicin, magnetic nanoparticles, and 17-allylamino-17-demethoxygeldanamycin. The nanofiber exhibits distinct hyperthermia, owing to the presence of magnetic nanoparticles upon exposure of the mesh to an alternating magnetic field, which causes heat-induced cell killing as well as enhanced chemotherapeutic efficiency of doxorubicin. The effectiveness of hyperthermia is further enhanced through the inhibition of heat shock protein activity after hyperthermia by releasing the inhibitor 17-allylamino-17-demethoxygeldanamycin. These findings represent a smart nanofiber system for potent cancer therapy and may provide a new approach for the development of localized medication delivery.     

Rational Design of Potent Inhibitors of a Metallohydrolase Using a Fragment-Based Approach

Metallohydrolases form a large group of enzymes that have fundamental importance in a broad range of biological functions. Among them, the purple acid phosphatases (PAPs) have gained attention due to their crucial role in the acquisition and use of phosphate by plants and also as a promising target for novel treatments of bone-related disorders and cancer. To date, no crystal structure of a mammalian PAP with drug-like molecules bound near the active site is available. Herein, we used a fragment-based design approach using structures of a mammalian PAP in complex with the Maybridge^TM fragment CC063346, the amino acid L-glutamine and the buffer molecule HEPES, as well as various solvent molecules to guide the design of highly potent and efficient mammalian PAP inhibitors. These inhibitors have improved aqueous solubility when compared to the clinically most promising PAP inhibitors available to date. Furthermore, drug-like fragments bound in newly discovered binding sites mapped out additional scaffolds for further inhibitor discovery, as well as scaffolds for the design of inhibitors with novel modes of action.     

Beneficial Changes in Rat Vascular Endocannabinoid System in Primary Hypertension and under Treatment with Chronic Inhibition of Fatty Acid Amide Hydrolase by URB597

Our study aimed to examine the effects of hypertension and the chronic administration of the fatty acid amide hydrolase (FAAH) inhibitor URB597 on vascular function and the endocannabinoid system in spontaneously hypertensive rats (SHR). Functional studies were performed on small mesenteric G3 arteries (sMA) and aortas isolated from SHR and normotensive Wistar Kyoto rats (WKY) treated with URB597 (1 mg/kg; twice daily for 14 days). In the aortas and sMA of SHR, endocannabinoid levels and cannabinoid CB₁ receptor (CB₁R) expression were elevated. The CB₁R antagonist AM251 diminished the methanandamide-evoked relaxation only in the sMA of SHR and enhanced the vasoconstriction induced by phenylephrine and the thromboxane analog U46619 in sMA in SHR and WKY. In the sMA of SHR, URB597 elevated anandamide levels, improved the endothelium-dependent vasorelaxation to acetylcholine, and in the presence of AM251 reduced the vasoconstriction to phenylephrine and enhanced the vasodilatation to methanandamide, and tended to reduce hypertrophy. In the aortas, URB597 elevated endocannabinoid levels improved the endothelium-dependent vasorelaxation to acetylcholine and decreased CB₁R expression. Our study showed that hypertension and chronic administration of URB597 caused local, resistance artery-specific beneficial alterations in the vascular endocannabinoid system, which may bring further advantages for therapeutic application of pharmacological inhibition of FAAH.     

IκB激酶β在肿瘤中的作用及其抑制剂的研究进展

近年来，IκB激酶β（inhibitor kappa B kinaseβ, IKKβ）在肿瘤发生发展过程中的作用逐渐被发现。IKKβ通过作用多种分子通路参与肿瘤细胞增殖、存活等过程，抑制IKKβ已被确定为治疗癌症有希望的手段。研究人员开发一系列IKKβ抑制剂，发现它们能够有效抑制肿瘤的生长，但目前尚无IKKβ抑制剂投入到临床上治疗癌症。在这篇综述中，我们将介绍IKKβ介导肿瘤发生发展及主要IKKβ抑制剂的研究进展。     

Soybean Trypsin Inhibitor Assay: Further Improvement of the Standard Method Approved and Reapproved by American Oil Chemists’ Society and American Association of Cereal Chemists International

For measuring trypsin inhibitor (TI) activities in soybean products, the current standard method, approved and reapproved by American Oil Chemists Society (Method Ba 12-75) and American Association of Cereal Chemists International (Method 22-40.01), features mixing trypsin with a series of inhibitor levels and then adding a substrate to start the colorimetric reaction. Yet, previous studies have shown flaws with the method, particularly with using several inhibitor levels and the sequence of adding the substrate last. The present study showed that with varying levels of dilution and volumes of a dilute sample extract, the pH of the premix (the mixture of a dilute sample extract and trypsin solution) ranged 3.30–3.60 for raw soy flour, and 3.20–6.70 for toasted soy. Within these premix pH ranges, the standard method of adding substrate last would give TI values equal to or less than those measured by the same method except for adding the enzyme last. The standard method was subsequently improved by using a single sample extract level and the enzyme-last sequence. Other modifications included making stock solutions for reagents, adding Ca²⁺ to the trypsin solution, diluting sample extracts to a level that causes 30–70% of inhibition, and running both reference and sample blanks for better controls. Alternatively, the full volume assay (10 mL total, as in the standard method) was further modified by using half the volume of each reagent with the same concentration. Compared to the standard method, the improved methods gave more consistent results when assaying 11 selected soy products. The half volume (5 mL) and full volume methods gave the same results, but the former could increase assay sensitivity and reduce amounts of reagents used.     

Btk/JAK3双靶点共价抑制剂的设计、合成及其活性研究

布鲁顿式酪氨酸激酶(Btk)和两面神激酶3(JAK3)均是自身免疫性疾病和血液系统恶性肿瘤的潜力靶标。以4-氯吡咯并嘧啶为原料,经7步反应合成了一系列7H-吡咯并[2,3-d]嘧啶-4-胺衍生物,其结构经¹HNMR、¹³CNMR和MS(ESI)分析证实。体外依次考察了所得化合物分别对Btk和JAK3激酶的活性、以及对部分B淋巴细胞瘤细胞系的抗增殖活性。结果表明,四氢吡咯烷基取代的衍生物NB1~4对Btk(IC₅₀<3 nmol/L)和JAK3(IC₅₀<165 nmol/L)均能有效抑制,其余化合物只对Btk显示抑制效果;而且NB2和NB4对所测试的多种B细胞淋巴瘤细胞系的抗增殖活性均优于阳性对照泛激酶抑制剂依鲁替尼及Btk单靶点抑制剂。其中,对Jeko-1细胞的抑制能力最佳(IC₅₀<3μmol/L),其次是OCI-LYI(IC₅₀<4μmol/L)、SUDHL-6(IC₅₀<6μmol/L)和HBL-1^*(IC₅₀<6.5μmol/L),最差为SUDHL-4细胞(IC₅₀<11μmol/L)。这些发现可为开发B细胞淋巴瘤的多靶点药物提供新的思路。     

复合香辛料亚硝化抑制剂对西式培根品质的影响

研究对N-亚硝胺具有阻断作用的复合香辛料亚硝化抑制剂（composite spice nitrosation inhibitor，CSNI） 在西式培根中的应用效果。设计4 组实验：1）阴性对照（negative control，NC）组：以原料肉质量计，配 制由0.06%亚硝酸钠、9%食盐、1.5%复合磷酸盐、5%白糖等组成的腌制液，注射量为20%；2）阳性对照 （positive control，PC）组：在NC组基础上添加0.055%异抗坏血酸钠；3）CSNI组：在NC组中添加CSNI； 4）PC＋CSNI组：在PC组中添加CSNI。制成西式培根，分别对西式培根成品和烧烤（200 ℃，5 min）西式培根进 行感官评定、pH值、红度值（a*）、硫代巴比妥酸反应物（thiobarbituric acid reactive substances，TBARs）值、亚 硝酸盐残留量、生物胺含量及N-亚硝胺含量测定。结果表明：相比NC、PC组，PC＋CSNI组西式培根成品的感官 评分最高，TBARs值（0.24 mg/kg）、亚硝酸盐残留量（20.48 mg/kg）和生物胺总量（184.68 mg/kg）均处于较低 水平，CSNI对N-亚硝胺的形成（总量为9.29 μg/kg），特别是N-二甲基亚硝胺的形成有显著的阻断效果，且CSNI的 添加对产品的pH值和a*均未造成显著影响；西式培根烧烤后，由于水分和脂肪溶出，致使烧烤西式培根的亚硝酸 盐残留量、生物胺含量和N-亚硝胺含量总体呈升高趋势，但均未超过相关规定的限量值。     

Corrosion behaviour of AA2024 aluminium alloy in different tempers in NaCl solution and with the CeCl3 corrosion inhibitor

The paper analyses the corrosion behaviour of naturally and artificially aged AA2024 alloy in NaCl solution and in the presence of an environment-friendly corrosion inhibitor, CeCl₃. On the basis of the values of polarisation resistance and corrosion current density, the corrosion resistance of the protective inhibitor film is established as well as the general corrosion resistance of this aluminium alloy. Resistance to pit formation is determined based on the difference in pitting and corrosion potentials while resistance to pit growth is determined based on the amount of charge consumed during pit growth. A scanning electron microscope is used to examine the morphology of the pits formed during the pitting corrosion testing, as well as to determine the cerium content on intermetallic particles and the matrix AA2024 alloy. The corrosion behaviour of AA2024 alloy is investigated after different test periods in NaCl solution and in the same solution with the CeCl₃ inhibitor. The corrosion resistance of both tempers of AA2024 alloy is more than one order of magnitude higher in the presence of CeCl₃. An explanation of the observed differences in the corrosion behaviour of the naturally and artificially aged AA2024 alloy is proposed. Different corrosion behaviour of the alloy after different test periods is also explained.