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1.
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.
Summary Human blood monocytes were isolated by counter-flow centrifugal elutriation from healthy donors and these noncytotoxic monocytes were rendered tumoricidal to allogeneic melanoma (A375) cells by activation with a synthetic acyltripeptide (FK-565), as assessed by measuring release of [125I]iododeoxyuridine in 72 h. When monocytes were treated with FK-565 for 16 h, and then fixed with paraformaldehyde, they showed cytotoxicity to A375 melanoma cells. The fixed-monocyte-mediated cytotoxicity to A375 cells was induced by the synergistic actions of FK-565 and recombinant interferon- (rIFN-), but not other cytokines [rIFN-A, rIFN-, tumor necrosis factor (TNF), interleukin (IL)-2, -3 and -6]. For synergistic activation of monocytes with induction of a membrane-associated antitumor monokine, the monocytes had to be incubated first with rIFN- and then with FK-565. FK-565 also acted synergistically with rIFN- to stimulate monocytes to produce membrane-associated IL-1 activity, which induced C3H/HeJ thymocyte blastogenesis in response to phytohemagglutinin P. The tumoricidal and thymocytestimulating activities of the fixed monocytes were almost completely inhibited by a specific anti-(IL-1) antiserum, but not by a specific anti-(IL-1) antiserum or monoclonal anti-TNF antibody. These results suggest that membrane-associated IL-1 of human blood monocytes can be induced by two activation signals (rIFN- then FK-565) at their suboptimal concentrations.Abbreviations IL interleukin - IFN interferon - TNF tumor necrosis factor  相似文献   
3.
We sequenced the 16S rRNA gene in mitochondrial DNA to characterize mithun located in Bhutan and to increase our understanding of its origin. We compared mithun with yak, European cattle, Bhutanese zebu and Indian zebu. Sequencing revealed low nucleotide diversity within the mithun population and their phylogenetic proximity to gaur. A close relationship between Bhutanese mithun and gaur was confirmed by an additional comparison with wild gaur specimens from three locations in Bhutan. Direct domestication of mithun from gaur was supported, while maternal contribution from the cattle lineage during domestication was not supported.  相似文献   
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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 beta-carotene-bovine serum albumin complexes could be obtained. Chls in the Chl-bovine serum albumin complexes had the following characteristics. 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. Both Chls in the bovine serum albumin-complexes were stable against oxidative stresses, such as photobleaching, Fenton reagent, peroxidase-H2O2 system. But 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   
8.
A method has been devised for the quantitative separation of trace amounts of alditols from mixtures with large amounts of monosaccharides, using a strongly basic ion-exchange resin. Ten kinds of common reducing monosaccharides used were strongly retained by a very basic anion-exchange resin in the hydroxyl form, whereas the corresponding alditols showed no significant affinity for the basic resin. Model studies showed excellent recoveries of alditol from known mixtures of alditol and the corresponding aldose at ratios in the range from 1 : 1X10(3) TO 1 : 1X10(4) (by weight). Application of this procedure to dextrans after reduction and hydrolysis resulted in quantitative separation of the terminal alditol.  相似文献   
9.
OBJECTIVE: To evaluate cytologic differences between primary pulmonary adenocarcinomas showing enteric differentiation (PAED) primary pulmonary adenocarcinomas of ordinary structure (PAC) and pulmonary metastases from colorectal carcinomas (MCR). STUDY DESIGN: During an 18-year period (1986-2003), cytologic materials were obtained from 5 PAEDs confirmed by pathologic examination of surgically resected specimens at the Cancer Institute Hospital. Aspiration cytologic and/or imprint smears of routine samples stained by the Papanicolaou method from the PAED cases were reviewed in comparison with 10 cases each of PAC showing a tubular pattern and MCR. RESULTS: The aspiration biopsy cytology and imprints showed similar features. Abundant necrotic debris in the background was recognized in a majority of all cases independent of the group. None to slight overlapping of tumor cells and less frequent palisading or glandular arrangements were characteristic features of PAED, significantly differing from MCR. Moreover, differences in nuclear features were evident as follows: in the MCR group, nuclear chromatin was hyperchromatic and coarsely condensed, and there were prominent nucleoli, whereas a slightly hyperchromatic pattern with some small to enlarged nucleoli was typical of PAED and PAC cases. CONCLUSION: Although diagnosis of PAED by routine cytology is difficult due to the features of the lesion, differential diagnosis between PAED, PAC and MCR is a possible using conventional cytologic criteria.  相似文献   
10.
It is speculated that bradykinin may play an important role in asthma. Thus, bradykinin receptor antagonists may have therapeutic potential against asthma. Orally active bradykinin antagonists would be more desirable for the treatment of the disease. In the present study, we examined the effects of a novel, potent, selective, and orally active nonpeptide bradykinin B2 receptor antagonist, FR167344 (N-[N-[3-[(3-bromo-2-methylimidazo[1,2-a]pyridin-8-yl)oxymethyl]-2 ,4-dichlorophenyl]-N-methylaminocarbonylmethyl]-4-(dimethylamin ocarbonyl)cinnamylamide hydrochloride), on guinea-pig tracheal smooth muscle bradykinin receptors. FR167344 inhibited [3H]bradykinin binding to bradykinin receptors in epithelium-denuded guinea-pig tracheal membrane with an IC50 of 2.1 nM and a Ki of 0.44 nM. This compound also inhibited bradykinin-induced contraction of epithelium-denuded guinea-pig trachea with a pK(B) of 10.8, but had no effect on carbachol-induced contraction of the trachea even at 10(-6) M. These results indicate that FR167344 has the specific antagonistic activity against guinea-pig tracheal smooth muscle bradykinin receptors.  相似文献   
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