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131.
Denise Utami Putri Ning Rintiswati Sofia Mubarika Haryana 《Natural product research》2018,32(4):463-467
Disease progression in Tuberculosis (TB) is dependent on host’s immune system. Phyllanthus niruri, a traditional herb, has long been used to boost immune system in Indonesian society. This study aimed to observe the potential role of P. niruri in inducing immune cells activity in TB patients by in vitro approach. Peripheral blood mononuclear cells (PBMCs) and macrophages were collected from active pulmonary TB patients. After stimulation with graded doses of P. niruri aqueous extract, cell proliferation, phagocytic activity and nitric oxide (NO) release were analysed. P. niruri aqueous extract induced proliferation of PBMCs, increased NO release, and improved macrophages phagocytic activity. These effects were observed in a dose-dependent manner. This may lead to further research for the potential role of P. niruri as immunomodulatory adjuvant therapy for TB patients. 相似文献
132.
Antoine Versini Lou Saier Fabien Sindikubwabo Sebastian Müller Tatiana Cañeque Raphaël Rodriguez 《Tetrahedron》2018,74(39):5585-5614
Cancer stem cells (CSC) have been shown to be refractory to conventional therapeutic agents, can promote metastasis, and have been linked to cancer relapse. The natural product Salinomycin has been identified by means of high throughput phenotypic screening as a selective killer of CSC in vitro and in vivo. In this article we comprehensively review the chemistry of Salinomycin, documenting early total syntheses, along with strategies that have been developed over the years to effectively modify this natural product at key positions with the view to establish a robust structure-activity-relationship and to delineate the complex mechanism of action of this fascinating molecule in the context of cancer research. Then, we document the biology of Salinomycin, putting forward phenotypic alterations that have been observed in the relevant biological models and highlighting how chemistry has been instrumental in discovering unprecedented physiological features of cancer stem cells that can be exploited for therapeutic benefits. 相似文献
133.
《Journal of separation science》2018,41(18):3561-3568
Monodisperse silica spheres that comprised a rhombic‐dodecahedral zeolitic imidazolate framework core–shell microsphere were applied in the sample pretreatment of navel orange. A rapid and efficient liquid chromatography with triple quadrupole tandem mass spectrometry method was established for simultaneously quantifying four plant growth regulators, 6‐benzylaminopurin, indole‐3‐acetic acid, indolepropionic acid, 3‐indolebutyric acid, in navel oranges. A satisfactory result was obtained, i.e., the peak area of the four plant growth regulators against concentration was linear with good correlation coefficients of 0.99987–0.99991. Under optimized conditions, the limits of detection were 3.0–59.4 μg/L for the four plant growth regulators. This method was applied to the simultaneous analysis of the four plant growth regulators in commercial samples, and all the detections were confirmed by acquiring transitions for each pesticide in the samples. 相似文献
134.
135.
燃煤电站布袋除尘器和静电除尘器脱汞性能比较 总被引:8,自引:0,他引:8
采用国际上通用的Ontario Hydro方法(OHM)对中国五个燃煤电站布袋除尘器(FF)/静电除尘器(ESP)前、后的烟气进行采样,应用美国EPA标准方法测定了烟气中Hg0、Hg2+和HgP的浓度。应用DMA80测定固体样品(煤、底灰、ESP飞灰)中的汞浓度。由汞平衡得出各个环节中汞所占的份额。由此得到FF和ESP脱除烟气中汞的性能。安装FF的电站1和2的综合脱除效率约为80%和20%,安装ESP的电站3、4和5的综合脱除效率分别为6%、20%和4%左右。这说明FF比ESP有更加优良的脱汞性能,而且FF/ESP脱除烟气中的汞受到很多因素的影响。 相似文献
136.
《Mendeleev Communications》2023,33(1):1-8
This focus article presents the author’s view on the problems in the development of biorefining strategies based on the use of 5-(hydroxymethyl)furfural (HMF), the key product derived from renewable plant biomass that was recognized as the ‘sleeping giant’ of the sustainable chemistry. The several key problems that hinder the large-scale production of HMF and its applicability in the laboratory organic synthesis and industry are discussed. This minireview is also focused on the development of the dynamic cross-linked polymers with controlled three-dimensional structure based on Diels–Alder reaction of biobased HMF-derived furans with maleimides. Realization of scalable technologies for an efficient production of such ‘smart’ analogues of the traditional petrochemical-based materials could be the basis for the realization of the competitive HMF-promoted biorefining. 相似文献
137.
Lingpu Zhang Nicolás Montesdeoca Dr. Johannes Karges Prof. Dr. Haihua Xiao 《Angewandte Chemie (International ed. in English)》2023,62(21):e202300662
Cancer is one of the deadliest diseases worldwide. Recent statistics have shown that metastases and tumor relapse are the leading causes of cancer-associated deaths. While traditional treatments are able to efficiently remove the primary tumor, secondary tumors remain poorly accessible. Capitalizing on this there is an urgent need for novel treatment modalities. Among the most promising approaches, increasing research interest has been devoted to immunogenic cell death inducing agents that are able to trigger localized cell death of the cancer cells as well as induce an immune response inside the whole organism. Preliminary studies have shown that immunogenic cell death inducing compounds could be able to overcome metastatic and relapsing tumors. Herein, the application of metal complexes as immunogenic cell death inducing compounds is systematically reviewed. 相似文献
138.
Asma Mani Tao Feng Albert Gandioso Robin Vinck Anna Notaro Lisa Gourdon Pierre Burckel Bruno Saubaméa Olivier Blacque Kevin Cariou Jamel-Eddine Belgaied Hui Chao Gilles Gasser 《Angewandte Chemie (International ed. in English)》2023,62(20):e202218347
Five osmium(II) polypyridyl complexes of the general formula [Os(4,7-diphenyl-1,10-phenanthroline)2 L ]2+ were synthesized as photosensitizers for photodynamic therapy by varying the nature of the ligand L . Thanks to the pronounced π-extended structure of the ligands and the heavy atom effect provided by the osmium center, these complexes exhibit a high absorption in the near-infrared (NIR) region (up to 740 nm), unlike related ruthenium complexes. This led to a promising phototoxicity in vitro against cancer cells cultured as 2D cell layers but also in multicellular tumor spheroids upon irradiation at 740 nm. The complex [Os(4,7-diphenyl-1,10-phenanthroline)2(2,2′-bipyridine)]2+ was found to be the most efficient against various cancer cell lines, with high phototoxicity indexes. Experiments on CT26 tumor-bearing BALB/c mice also indicate that the OsII complexes could significantly reduce tumor growth following 740 nm laser irradiation. The high phototoxicity in the biological window of this structurally simple complex makes it a promising photosensitizer for cancer treatment. 相似文献
139.
Siriphong Somprasong Dr. Marta Castiñeira Reis Prof. Dr. Syuzanna R. Harutyunyan 《Angewandte Chemie (International ed. in English)》2023,62(9):e202217328
Nitrogen-bearing rings are common features in the molecular structures of modern drugs, with chiral δ-lactams being an important subclass due to their known pharmacological properties. Catalytic dearomatization of preactivated pyridinium ion derivatives emerged as a powerful method for the rapid construction of chiral N-heterocycles. However, direct catalytic dearomatization of simple pyridine derivatives are scarce and methodologies yielding chiral δ-lactams are yet to be developed. Herein, we describe an enantioselective C4-dearomatization of methoxypyridine derivatives for the preparation of functionalised enantioenriched δ-lactams using chiral copper catalysis. Experimental 13C kinetic isotope effects and density functional theory calculations shed light on the reaction mechanism and the origin of enantioselectivity. 相似文献
140.
Ganghao Liang Dr. Tumpa Sadhukhan Dr. Samya Banerjee Dongsheng Tang Hanchen Zhang Minhui Cui Nicolás Montesdeoca Dr. Johannes Karges Prof. Dr. Haihua Xiao 《Angewandte Chemie (International ed. in English)》2023,62(22):e202301074
The development of PtIV prodrugs that are reduced into the therapeutically active PtII species within the tumor microenvironment has received much research interest. In order to provide spatial and temporal control over the treatment, there is a high demand for the development of compounds that could be selectively activated upon irradiation. Despite recent progress, the majority of PtIV complexes are excited with ultraviolet or blue light, limiting the use of such compounds to superficial application. To overcome this limitation, herein, the first example of PtIV prodrug nanoparticles that could be reduced with deeply penetrating ultrasound radiation is reported, enabling the treatment of deep-seated or large tumors. The nanoparticles were found to selectively accumulate inside a mouse colon carcinoma tumor upon intravenous injection and were able to eradicate the tumor upon exposure to ultrasound radiation. 相似文献