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1.
Hitoshi Shibata Hideo Ochiai Tetsufumi Kawashima Tadayoshi Okamoto Isamu Inamura 《BBA》1986,852(2-3):175-182
By mixing chlorophyll (Chl) a or b with a dense bovine serum albumin solution, the water-soluble Chl-bovine serum albumin complexes were prepared. These complexes, eluted near the void volume on a gel filtration, were separated well from unreacted bovine serum albumin, indicating an aggregation of such molecules in the complexes. Preparation of chlorophyllide (Chlide) a- or Chlide b-bovine serum albumin complex was unsuccessful, while the phytol-, and β-carotene-bovine serum albumin complexes could be obtained. Chls in the Chl-bovine serum albumin complexes had the following characteristics. (i) Main absorption peak of Chl a or b in the red region occurred at 675 nm or 652 nm, respectively. The Chl a-bovine serum albumin complex having absorption peak at 740 nm was also prepared. As compared with the stabilities of Chl a and b in Triton X-100. (ii) Both Chls in the bovine serum albumin-complexes were stable against oxidative stresses, such as photobleaching, Fenton reagent, peroxidase-H2O2 system. But (iii) they were easily hydrolyzed by chlorophyllase. These properties of Chls in the bovine serum albumin-complexes were similar to those of Chls in the isolated light-harvesting Chl a/b protein complex. A possible localization of Chls within the bovine serum albumin complexes was suggested that the porphyrin moiety of Chl was buried in bovine serum albumin; however, the hydrophilic edge of porphyrin ring, adjacent to the phytol group, occurred in the hydrophilic region of a bovine serum albumin molecule. 相似文献
2.
用共振拉曼和紫外-可见吸收光谱研究了水溶金属卟啉4-N-乙酸乙酯基-吡啶基铜卟啉和镍卟啉[简称Cu(NEAE)和Ni(NEAE)]及4-N-乙腈基-吡啶基铜卟啉[简称Cu(NACN)]与小牛胸腺DNA的相互作用。分析表明Cu(NEAE)、Ni(NEAE)和Cu(NACN)分别以外部键联、部分插入和沟槽方式与DNA作用;卟啉插入DNA时吡啶基团向卟啉环平面转动但不可能转成与之共面;而以非插入方式作用时吡啶基团会向垂直于或者平行于卟啉环平面转动。吡啶取代基的大小和空间位阻是影响相互作用方式的关键因素之一。 相似文献
3.
V. Sreenivasa Reddy Kattesh V. Katti Charles L. Barnes 《Inorganica chimica acta》1995,240(1-2):367-370
The water-soluble bisphosphine, 1,2-bis(bis(hydroxymethyl)phosphino)ethane (1), was synthesized in near quantitative yield by the reaction of bisphosphine, H2PCH2CH2PH2, with an aqueous formaldehyde in the presence of K2PtCl4. The reaction of this water-soluble bisphosphine 1 with cis-Pt(COD)Cl2 affords the mononuclear bischelate complex, [Pt{(HOH2C)2PCH2CH2P(CH2OH)2}2](Cl)2 (2), in near quantitative yield. The new ligand and complex have been characterized spectroscopically and the structure of the metal complex, 2, was determined by X-ray crystallography. The Pt(II) complex 2 crystallizes in the orthorhombic space group Pbca(a=14.623(1), B=16.216(2), C=9.319(4) Å) with Z=4. The final R value is 0.024. 相似文献
4.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):614-617
This article describes the photodynamic inactivation of mosquito iridescent virus (MIV) Aedes flavescens in the presence of water-soluble C60 fullerenes. It has been observed that the photodynamic inactivation of MIV for about 1?h reduces the infectious titre of the virus in large wax-moth larvae Galleria mellonella to 4.5 lg ID50/mL. The influence of the C60 concentration on its anti-viral activity was tested in the concentration range from 1 to 0.001?mg/mL. It has been found that C60 is able to inactivate the iridovirus even in low concentrations. Consequently, the findings of this work suggest that photoexcited C60 fullerenes can be successfully used for the inactivation of iridoviruses in biological systems. 相似文献
5.
The water-soluble fraction of bee venom produces antinociceptive and anti-inflammatory effects on rheumatoid arthritis in rats 总被引:2,自引:0,他引:2
We recently demonstrated that bee venom (BV) injection into the Zusanli acupoint produced a significantly more potent anti-inflammatory and antinociceptive effect than injection into a non-acupoint in a Freund's adjuvant induced rheumatoid arthritis (RA) model. However, the precise BV constituents responsible for these antinociceptive and/or anti-inflammatory effects are not fully understood. In order to investigate the possible role of the soluble fraction of BV in producing the anti-arthritic actions of BV acupuncture, whole BV was extracted into two fractions according to solubility (a water soluble fraction, BVA and an ethylacetate soluble fraction, BVE) and the BVA fraction was further tested.Subcutaneous BVA injection (0.9 mg/kg/day) into the Zusanli acupoint was found to dramatically inhibit paw edema and radiological change (i.e. new bone proliferation and soft tissue swelling) caused by Freund's adjuvant injection. BVA treatment also reduced the increase in serum interleukin-6 caused by RA induction to levels observed in non-arthritic animals. In addition, BVA therapy significantly reduced arthritis-induced nociceptive behaviors (i.e. nociceptive scores for mechanical hyperalgesia and thermal hyperalgesia). Finally, BVA treatment significantly suppressed adjuvant-induced Fos expression in the lumbar spinal cord at 3 weeks post-adjuvant injection. In contrast, BVE treatment (0.05 mg/kg/day) failed to show any anti-inflammatory or antinociceptive effects on RA.The results of the present study demonstrate that BVA is the effective fraction of whole BV responsible for the antinociception and anti-inflammatory effects of BV acupuncture treatment. Thus it is recommended that this fraction of BV be used for long-term treatment of RA-induced pain and inflammation. However, further study is necessary to clarify which constituents of the BVA fraction are directly responsible for these anti-arthritis effects. 相似文献
6.
New water-soluble rhodium(III) complexes with a tacn (1,4,7-triazacyclononane) and a bpy (2,2′-bipyridine) supporting ligands were synthesized. The reaction of [RhIII(tacn)Cl3] (1) with equimolar amount of bpy and two equivalents of AgNO3 in H2O at reflux for 10 h gave a water-soluble chloro complex [RhIII(tacn)(bpy)Cl](NO3)2 {2(NO3)2}. Complex 2(NO3)2 was treated with equimolar amount of AgNO3 in H2O at reflux for 10 h to give a water-soluble nitrato complex [RhIII(tacn)(bpy)(NO3)](NO3)2 {3(NO3)2}. Water-solubility of 3 with NO3 − ligand (46.5 mg/mL) is high compared with that of 2 with Cl− ligand (14.5 mg/mL) under the same conditions (at pH 7.0 at 25 °C). The structures of 2 and 3 were unequivocally determined by X-ray analysis. Their structures in H2O were also examined by 1H NMR, IR, and electrospray ionization mass spectrometry (ESI-MS). 相似文献
7.
Jessica L. Bongiovanni Patrick T. Fadden Kirsten R. Wells Elizabeth T. Papish Glenn P.A. Yap 《Inorganica chimica acta》2010,363(10):2163-7533
Tris(triazolyl)borate (Ttz) ligands are sterically similar to tris(pyrazolyl)borate (Tp) but complexes of Ttz show improved solubility in water and alcohols due to their propensity for forming hydrogen bonds. Recently developed bulky tris(triazolyl)borate ligands can produce four and five coordinate transition metal complexes and serve as models for enzyme active sites in an aqueous environment. Herein we report the synthesis of such complexes, i.e. (TtztBu,Me)ZnCl, (TtztBu,Me)ZnBr, (TtztBu,Me)NiCl, and (TtztBu,Me)CuCl, which were analyzed by X-ray crystallographic and spectroscopic methods [TtztBu,Me = tris(3-t-butyl-5-methyl-1,2,4-triazolyl)borate]. (TtztBu,Me)ZnCl crystallizes as two different polymorphs with cubic and monoclinic symmetry. Both polymorphs of (TtztBu,Me)ZnCl and (TtztBu,Me)ZnBr have tetrahedral zinc atoms whereas the geometries at the metal in (TtztBu,Me)NiCl and (TtztBu,Me)CuCl are distorted tetrahedral. All complexes are methanol soluble and they also dissolve in methanol/water mixtures with up to 60% water. 相似文献
8.
Water-soluble quantum dots for biomedical applications 总被引:6,自引:0,他引:6
Yu WW Chang E Drezek R Colvin VL 《Biochemical and biophysical research communications》2006,348(3):781-786
Semiconductor nanocrystals are 1-10nm inorganic particles with unique size-dependent optical and electrical properties due to quantum confinement (so they are also called quantum dots). Quantum dots are new types of fluorescent materials for biological labeling with high quantum efficiency, long-term photostability, narrow emission, and continuous absorption spectra. Here, we discuss the recent development in making water-soluble quantum dots and related cytotoxicity for biomedical applications. 相似文献
9.
Xyloglucan, a water-soluble food grade polysaccharide, was reported as a substrate for graft copolymerization of methyl methacrylate (MMA). Grafting PMMA (polymethyl methacrylate) with xyloglucan (XG) makes a new material with improved thermal stability and shelf life without affecting its hydrophilicity. XG was isolated from tamarind seed mucilage by aqueous extraction. Grafting of MMA was initiated by ceric ion in aqueous medium under N2 atmosphere and the progress of the reaction was monitored gravimetrically by varying different reaction parameters. Grafting of MMA onto XG was confirmed by FTIR spectroscopy, NMR spectroscopy, differential scanning calorimetric (DSC) studies, thermal gravimetric analysis (TGA) studies and scanning electron micrographs (SEMs). This material might find potential to be used in drug delivery systems. 相似文献