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Ulrich Weser Karl-Heinz Sellinger Edmund Lengfelder Walther Werner Joachim Strähle 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,631(2):232-245
The copper complex of indomethacin (1-(p-chlorobenzoyl)-5-methoxy-2-methyl-indole acetate), a common anti-inflammatory drug, was prepared and characterized. Crystal structure determination revealed the dimeric form of the 1:2 complex, namely Cu2(indomethacin)4 · L2, in the unit cell. Suprisingly, the copper-copper distance (263 pm) was very close to metallic copper (256 pm). The two coordination sites in the copper-copper axis can be readily replaced by superoxide. An intriguing similarity to Cu2(acetate)4 was seen.Due to the lipophilic nature of the indomethacin ligand, this copper complex reacted with superoxide in aprotic solvents. The superoxide dismutating activity was successfully demonstrated in Me2SO/water and acetonitrile/water mixtures using the nitro-blue tetrazolium assay and pulse radiolysis. The second-order rate constant of 6 · 109 M?1 · s?1 in strictly aqueous systems dropped only slightly to 1.1 · 109 M?1 · s?1 when aprotic solvents were used. This is the fastest rate constant ever observed for a copper-dependent dismutation of superoxide. The KO2-induced lipid peroxidation in both erythrocytes and liver microsomes was suppressed by 70% in the presence of 1 · 10?10 mol · ml?1 of Cu2(indomethacin)4. The inhibitory action dropped to 25% when Cu2Zn2superoxide dismutase was employed. The formation of copper · indomethacin in rat serum after administration of indomethacin was shown in vitro and in vivo. 相似文献
4.
Current and emerging commercial optical biosensors. 总被引:5,自引:0,他引:5
The field of commercial optical biosensors is rapidly evolving, with new systems and detection methods being developed each year. This review outlines the currently available biosensor hardware and highlights unique features of each platform. Affinity-based biosensor technology, with its high sensitivity, wide versatility and high throughput, is playing a significant role in basic research, pharmaceutical development, and the food and environmental sciences. Likewise, the increasing popularity of biosensors is prompting manufacturers to develop new instrumentation for dedicated applications. We provide a preview of some of the emerging commercial systems that are dedicated to drug discovery, proteomics, clinical diagnostics and routine biomolecular interaction analysis. 相似文献
5.
Prasert Akkaramongkolporn Tanasait Ngawhirunpat Praneet Opanasopit 《AAPS PharmSciTech》2009,10(2):641-648
The differently sulfonated styrene–divinylbenzene cross-linked copolymer cationic exchange resins were prepared by oil-in-water
polymerization and varied degrees of sulfonation. Several characteristics of the obtained resins were evaluated, i.e., Fourier
transform infrared spectra, the ion-exchange capacity, microscopic morphology, size, and swelling. The resin characteristics
were altered in relation to the degree of sulfonation, proving that differently sulfonated resins could be prepared. The behavior
of chlorpheniramine (CPM) loading and in vitro release in the USP simulated gastric (SGF) and intestinal fluids (SIF) of the obtained resins were also evaluated. The CPM
loaded in the resinates (drug-loaded resins) increased with the increasing degree of sulfonic group and hence the drug binding
site in the employed resins. The CPM release was lower from the resins with the higher degree of sulfonic group due to the
increase in the diffusive path depth. The CPM release was obviously lower in SGF than SIF because CPM, a weak base drug, ionized
to a greater extent in SGF and then preferred binding with rather than releasing from the resins. In conclusion, the differently
sulfonated resins could be utilized as novel carriers for drug delivery. 相似文献
6.
Mahsa Zahiri Maryam Babaei Khalil Abnous Seyed Mohammad Taghdisi Mohammad Ramezani Mona Alibolandi 《Journal of cellular physiology》2020,235(2):1036-1050
In this study, the chemical features of dendritic mesoporous silica nanoparticles (DMSNs) provided the opportunity to design a nanostructure with the capability to intelligently transport the payload to the tumor cells. In this regard, doxorubicin (DOX)-encapsulated DMSNs was electrostatically surface-coated with polycarboxylic acid dextran (PCAD) to provide biocompatible dextran-capped DMSNs (PCAD-DMSN@DOX) with controlled pH-dependent drug release. Moreover, a RNA aptamer against a cancer stem cell (CSC) marker, CD133 was covalently attached to the carboxyl groups of DEX to produce a CD133-PCAD-DMSN@DOX. Then, the fabricated nanosystem was utilized to efficiently deliver DOX to CD133+ colorectal cancer cells (HT29). The in vitro evaluation in terms of cellular uptake and cytotoxicity demonstrated that the CD133-PCAD-DMSN@DOX specifically targets HT29 as a CD133 overexpressed cancer cells confirmed by flow cytometry and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. The potentially promising intelligent-targeted platform suggests that targeted dextran-capped DMSNs may find impressive application in cancer therapy. 相似文献
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Silvia Pastorekova Daniela Vullo Angela Casini Andrea Scozzafava Jaromir Pastorek Isao Nishimori 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):211-217
The tumor-associated transmembrane carbonic anhydrase (CA, EC 4.2.1.1) isozymes IX (CA IX) and XII (CA XII) are involved in acidification of hypoxic tumors, a process correlated with poor prognosis and clinical outcome of patients harboring such tumors. This process may be reversed by inhibiting these enzymes with potent sulfonamide/sulfamate inhibitors. A series of such aromatic/heterocyclic sulfonamides incorporating 2,3,5,6-tetrafluorobenzoyl-, 2,3,5,6-tetrafluoro- phenylsulfonyl- and pentafluorophenylureido moieties has been investigated for its interaction with the catalytic domain of the human isozymes hCA IX and hCA XII. Some of these compounds showed excellent inhibitory properties against both isozymes IX and XII, with several subnanomolar inhibitors detected for the first time. These sulfonamides may constitute valuable candidates for the development of novel antitumor therapies based on the inhibition of such tumor-associated CA isozymes. 相似文献
9.
Wei Liu Yaoting Sun Weigang Ge Fangfei Zhang Lin Gan Yi Zhu Tiannan Guo Kexin Liu 《Molecular & cellular proteomics : MCP》2022,21(2):100187
Drug resistance is a critical obstacle to effective treatment in patients with chronic myeloid leukemia. To understand the underlying resistance mechanisms in response to imatinib mesylate (IMA) and adriamycin (ADR), the parental K562 cells were treated with low doses of IMA or ADR for 2 months to generate derivative cells with mild, intermediate, and severe resistance to the drugs as defined by their increasing resistance index. PulseDIA-based (DIA [data-independent acquisition]) quantitative proteomics was then employed to reveal the proteome changes in these resistant cells. In total, 7082 proteins from 98,232 peptides were identified and quantified from the dataset using four DIA software tools including OpenSWATH, Spectronaut, DIA-NN, and EncyclopeDIA. Sirtuin signaling pathway was found to be significantly enriched in both ADR-resistant and IMA-resistant K562 cells. In particular, isocitrate dehydrogenase (NADP(+)) 2 was identified as a potential drug target correlated with the drug resistance phenotype, and its inhibition by the antagonist AGI-6780 reversed the acquired resistance in K562 cells to either ADR or IMA. Together, our study has implicated isocitrate dehydrogenase (NADP(+)) 2 as a potential target that can be therapeutically leveraged to alleviate the drug resistance in K562 cells when treated with IMA and ADR. 相似文献
10.
Gerald Ozanne 《Aerobiologia》1990,6(1):8-10
Summary Under the ?Bois plus? scheme, the CTBA is currently developing a third party certification, based on the Scrivener law, with the aim of defending
the consumers' interests. At this early stage, wood preservatives and treated wood are checked for the efficacy of treatments
in order to ensure the stability and security of works in buildings and civil engineering. According to the different classes
of risks in service, ?Bois plus? provides the most adeguate level of protection. In the close future, the industry is planning to incorporate, with the help
of the CTBA and experts, health criteria within the frame of the ?Bois plus? certification scheme. The means could beSafety indexes, which are objectives of quality for professionals.Safety indexes are concentrations of substances in wood which can be taken as safe for humans and the general environment, while still toxic
for the wood pests.
This attractive experience aims to make with the brandname ?Bois plus? a synonym of efficacy and safety. This approach meets the essential requirements 1, 3, 4 of the 89/106 EEC directive: mechanical
resistance and stability/hygiene, health and environment/safety in use. 相似文献