首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
Human serum transferrin has a potential for drug-delivery systems. Oxalate and aziridine-carboxylate was conjugated to serum transferrin in order to transport into the targeted cancer cells via transferrin-receptor mediated endocytosis. Capillary zone electrophoresis and capillary isoelectric focusing were used to analyze the effectiveness of complexation reactions. The electropherograms show the differences between iron-free- and iron-complexed molecular forms of human serum transferrin. The iron-complexed transferrin sample containing the different anions as synergistic complexing agents were characterized by different electrophoretic parameters.  相似文献   

3.
Bis-thiourea Metal Complexes with Enhanced Antiphytoviral Activity   总被引:1,自引:0,他引:1  
The activity of bis-thiourea, diallyl-bis-thiourea and in part of diphenyl-bis-thiourea against potato virus X (PVX) can be augmented considerably by complexation of the mentioned compounds with Cu±±, Ni±±, and Co±±. Contrary to this, complexation with Fe±± and Cd±± does not augment or reduce the antiphytoviral activity. Most antiphytoviral active are the diallyl-bis-thiourea complexes with Cu±±, Ni±± and Co±±. The antiphytoviral activity of the Cu±± and Cd±± complexes with bisthiourea can be additionally augmented by combined treatment with small amounts of 2,4-dioxohexahydro-l,3,5-triazine (DHT).  相似文献   

4.
活性过氧钒配合物对酪氨酸磷酸酶的抑制作用   总被引:7,自引:0,他引:7  
  相似文献   

5.
Addition of thiosemicarbazide, 4‐allylthiosemicarbazide, and 4‐phenylthiosemicarbazide to (formylphenyl)boronic acids affords a series of thiosemicarbazones containing boronic acids. Addition of 2‐formylphenylboronic acid to the thiosemicarbazides gave the corresponding cyclic 2,3,1‐benzodiazaborines. All new compounds have been investigated for potential antifungal activity.  相似文献   

6.

Background

The serine/threonine kinase PIM2 is highly expressed in human leukemia and lymphomas and has been shown to positively regulate survival and proliferation of tumor cells. Its diverse ATP site makes PIM2 a promising target for the development of anticancer agents. To date our knowledge of catalytic domain structures of the PIM kinase family is limited to PIM1 which has been extensively studied and which shares about 50% sequence identity with PIM2.

Principal Findings

Here we determined the crystal structure of PIM2 in complex with an organoruthenium complex (inhibition in sub-nanomolar level). Due to its extraordinary shape complementarity this stable organometallic compound is a highly potent inhibitor of PIM kinases.

Significance

The structure of PIM2 revealed several differences to PIM1 which may be explored further to generate isoform selective inhibitors. It has also demonstrated how an organometallic inhibitor can be adapted to the binding site of protein kinases to generate highly potent inhibitors.

Enhanced version

This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.  相似文献   

7.
具靶向性的转铁蛋白—脂质体的制备   总被引:2,自引:0,他引:2  
具靶向性的转铁蛋白──脂质体的制备杨静平,王瓞,林其谁(中国科学院上海生物化学研究所分子生物学国家重点实验室,200031)关键词脂质体;人转铁蛋白;靶向性;癌细胞;天花粉蛋白利用正常细胞和癌细胞表面受体或抗原物质的差异,用相应配体修饰脂质体表面,使...  相似文献   

8.
Thiosemicarbazones (TSCs) are an interesting class of ligands that show a diverse range of biological activity, including anti-fungal, anti-viral and anti-cancer effects. Our previous studies have demonstrated the potent in vivo anti-tumor activity of novel TSCs and their ability to overcome resistance to clinically used chemotherapeutics. In the current study, 35 novel TSCs of 6 different classes were designed using a combination of retro-fragments that appear in other TSCs. Additionally, di-substitution at the terminal N4 atom, which was previously identified to be critical for potent anti-cancer activity, was preserved through the incorporation of an N4-based piperazine or morpholine ring. The anti-proliferative activity of the novel TSCs were examined in a variety of cancer and normal cell-types. In particular, compounds 1d and 3c demonstrated the greatest promise as anti-cancer agents with potent and selective anti-proliferative activity. Structure-activity relationship studies revealed that the chelators that utilized “soft” donor atoms, such as nitrogen and sulfur, resulted in potent anti-cancer activity. Indeed, the N,N,S donor atom set was crucial for the formation of redox active iron complexes that were able to mediate the oxidation of ascorbate. This further highlights the important role of reactive oxygen species generation in mediating potent anti-cancer activity. Significantly, this study identified the potent and selective anti-cancer activity of 1d and 3c that warrants further examination.  相似文献   

9.
International Journal of Peptide Research and Therapeutics - In the study, ten different Lactobacillus cultures were considered for the study of ɑ-amylase, ɑ-glucosidase and pancreatic...  相似文献   

10.
A series of nine polypyridyl-ruthenium (II) complexes (N-ligands = 2,2′-bipyridines; 2,2′-6′,2′-terpyridines, di-alkyloxy-2,2′-6,2-bipyridine-3,3′-di-carboxylates), were tested against Mycobacterium tuberculosis (MBT). The complex (11) showed remarkable activity against MBT as compared to other complexes, (1–10). The aquo ligand of complex (11), as opposed to other chloro and acetonitrile derivatives, appears to play a key role in the antitubercular potency of this new class of metal-based compounds.  相似文献   

11.
Washed or growing E. coli cells are killed by epinephrine, norepinephrine or dopamine in the presence of non lethal concentrations of Cu(II). Killing is enhanced by anoxia and by sublethal Concentrations of H2O1. The rate of killing is proportional to the rate of catecholamine oxidation. The copper epinephrine complex binds to E. coli cells, induces membrane damage and depletion of the cellular ATP pool. The cells may be partially protected by SOD or catalase but not by OH radical scavengers. Addition of H2O2 to cells which were sensitized by preincubation with the epinephrine-copper complex, causes rapid killing and DNA degradation. Sensitized cells are not protected by BSA.  相似文献   

12.
《Free radical research》2013,47(1):479-488
Washed or growing E. coli cells are killed by epinephrine, norepinephrine or dopamine in the presence of non lethal concentrations of Cu(II). Killing is enhanced by anoxia and by sublethal Concentrations of H2O1. The rate of killing is proportional to the rate of catecholamine oxidation. The copper epinephrine complex binds to E. coli cells, induces membrane damage and depletion of the cellular ATP pool. The cells may be partially protected by SOD or catalase but not by OH radical scavengers. Addition of H2O2 to cells which were sensitized by preincubation with the epinephrine-copper complex, causes rapid killing and DNA degradation. Sensitized cells are not protected by BSA.  相似文献   

13.
The antioxidant activity of dihydroquercetin (DHQ) complexes with zinc, copper(II) and calcium was studied in vitro in blood plasma of healthy donors. The state of lipid peroxidation (LPO) in blood plasma was assessed by the content of malondialdehyde (MDA), diene (DC) and triene (TC) conjugates. The effect of DHQ and the complexes on the activity of the catalase enzyme in blood plasma was determined. It was found that DHQ complex with zinc ion reduces the MDA content in blood plasma by 14.9% compared with the control, which is twice as high as for DHQ (7.5%). The corresponding parameters of DHQ complexes with copper(II) and calcium ions were 11.2 and 3.7%, respectively. The effect of the complexes on the decrease in the DC and TC content in blood plasma compared with the control is comparable with the corresponding parameters for DHQ. The DHQ complex with zinc ion increases the catalase activity by 1.5% compared with DHQ. The complexes containing copper(II) and calcium ions increase the catalase activity no more than DHQ.  相似文献   

14.
15.
The Protein Journal - As expected, several new variants of Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2) emerged and have been detected around the world throughout this Coronavirus...  相似文献   

16.
通过测定对羟自由基、超氧负离子自由基的清除率和还原能力,研究了壳聚糖、硫脲壳聚糖及5种硫脲壳聚糖金属配合物的抗氧化活性。结果表明:在实验设置的浓度范围内,对羟自由基的清除能力依次为硫脲壳聚糖Cu(Ⅱ)>硫脲壳聚糖Fe(Ⅱ)>硫脲壳聚糖Co(Ⅱ)>硫脲壳聚糖Ni(Ⅱ)>硫脲壳聚糖Zn(Ⅱ),且清除能力随着浓度的增加而增强;对超氧负离子自由基清除能力依次为硫脲壳聚糖Ni(Ⅱ)>硫脲壳聚糖Zn(Ⅱ)>硫脲壳聚糖Co(Ⅱ)>硫脲壳聚糖Cu(Ⅱ)>硫脲壳聚糖Fe(Ⅱ),且清除能力随着浓度的增加而增强;还原能力依次为硫脲壳聚糖Co(Ⅱ)>硫脲壳聚糖Cu(Ⅱ)>硫脲壳聚糖Fe(Ⅱ)>硫脲壳聚糖Ni(Ⅱ)>硫脲壳聚糖Zn(Ⅱ)。  相似文献   

17.
Recently the rise in noncommunicable diseases and side effects of drugs has promoted the research in food components with biologically active molecules. These bioactive components are vital in reducing and regulating the onset of such chronic degenerative diseases. Many food derived peptides are biologically active fragments encrypted within the primary protein sequence in nascent (inactive) form, hence also called ‘cryptides’. These bioactive peptides range in size from 2 to 50 amino acids. They function beyond their basic nutritional benefits. Upon oral administration, these peptides play various roles such as opiate like, antioxidative, immunomodulatory, antihypertensive, hypocholesterolemic, mineral binding, antiobesity and antimicrobial. Both animal and plant proteins are rich sources of bioactive peptides having specific physiological and biochemical functions. Digestion of proteins in vivo or in vitro produces free amino acids and peptides which enter circulatory system and exert systemic effect. Bioactive peptides can be produced in vivo through gastrointestinal digestion whereas in vitro through chemical processing of food proteins with acid, alkali, heat and enzymatic hydrolysis either by digestion or fermentation. Protein hydrolysates being rich source of bioactive peptides can serve as an alternative to intact protein and elemental formula in the development of functional foods.  相似文献   

18.
Five new copper and zinc heteroleptic complexes with saccharin and aminoacids with general stoichiometry Na2[M(sac)2(aa)2]⋅nH2O (M denotes Cu or Zn, sac the saccharinate ion, and aa the aminoacids) were synthesized and characterized by elemental and thermogravimetric analysis, conductimetric measurements and IR, Raman and UV–vis spectroscopies. In all the complexes, copper and zinc ions coordinated with the aminoacids through the terminal amine and carboxylate residues and with saccharin through the heterocyclic nitrogen atom. Besides, the superoxide dismutase-like activity of the heteroleptic copper complexes was evaluated and compared with the homoleptic copper amino acid complexes with the aim to observe the influence of the saccharin coordination.  相似文献   

19.
20.
食用菌因药食两用的特点被广泛研究,具有提升机体免疫,阻止和防御疾病的功能作用。不同食用菌中所含的生物活性组分不同,主要有:多糖类、蛋白类、萜类、生物碱类等,这些组分具有抗氧化、抗肿瘤、免疫调节、抗炎症反应、抗心血管疾病、抗细菌、抗辐射及抗糖尿病等功效,其中抗肿瘤作用研究居多,研究发现其分子作用机制主要通过调控细胞信号通路中相关因子表达水平抑制肿瘤细胞增殖,诱导细胞凋亡的,这为开发天然无毒性肿瘤药物制剂奠定了理论基础。针对食用菌不同生物活性组分抗肿瘤分子机制的最新研究进展展开简要综述。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号