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The order Cornales descends from the earliest split in the Asterid clade of flowering plants. Despite a few phylogenetic studies, relationships among families within Cornales remain unclear. In the present study, we increased taxon and character sampling to further resolve the relationships and to date the early diversification events of the order. We conducted phylogenetic analyses of sequence data from 26S rDNA and six chloroplast DNA (cpDNA) regions using parsimony (MP), maximum likelihood (ML), and Bayesian inference (BI) methods with different partition models and different data sets. We employed relaxed, uncorrelated molecular clocks on BEAST to date the phylogeny and examined the effects of different taxon sampling, fossil calibration, and data partitions. Our results from ML and BI analyses of the combined cpDNA sequences and combined cpDNA and 26S rDNA data suggested the monophyly of each family and the following familial relationships ((Cornaceae-Alangiaceae)-(Curtisiaceae-Grubbiaceae))-(((Nyssaceae-Davidiaceae)-Mastixiaceae)-((Hydrostachyaceae-(Hydrangeaceae-Loasaceae))). These relationships were strongly supported by posterior probability and bootstrap values, except for the sister relationship between the N-D-M and H-H-L clades. The 26S rDNA data and some MP trees from cpDNA and total evidence suggested some alternative alignments for Hydrostachyaceae within Cornales, but results of SH tests indicated that these trees were significantly worse explanations of the total data. Phylogenetic dating with simultaneous calibration of multiple nodes suggested that the crown group of Cornales originated around the middle Cretaceous and rapidly radiated into several major clades. The origins of most families dated back to the late Cretaceous except for Curtisiaceae and Grubbiaceae which may have diverged in the very early Tertiary. We found that reducing sampling density within families and analyzing partitioned data sets from coding and noncoding cpDNA, 26S rDNA, and combined data sets produced congruent estimation of divergence times, but reducing the number and changing positions of calibration points resulted in very different estimations. 相似文献
953.
The B27K-DTrI insulin (human insulin with B28-30 removed and B27 Thr replaced by Lys) was reported to have superior monomeric property with 80% insulin activity in vivo. It has potential use as a new fast-acting analog of insulin. We cloned the monomeric insulin B27 DTrI precursor (MIP) into the pTWIN1 vector, and prepared by intein mediated expression in Escherichia coli. After tryptic digestion, the MIP was converted to B27K-DTrI insulin. The product was purified by HPLC. The mass spectrometry showed that the molecular mass of purified B27K-DTrI was consistent with the theoretical value. 相似文献
954.
Shuo Huang Ping Zhao Liying Yang Yuan Chen Jie Yan Enkui Duan Jie Qiao 《Reproductive biology and endocrinology : RB&E》2011,9(1):1-8
Background
Sperm immobilizing activity and plausible mechanism of action of Chenopodium album seed decoction (CAD) have been elucidated in our earlier studies. The present study has been carried out to explore the safety standards of CAD along with microbicidal properties as prerequisite for its use as a topically applicable vaginal contraceptive.Methods
The safety standards of CAD were assessed by a) Hemolytic index determination using rabbit erythrocytes, to set the doses of the other experiments, b) Dermal irritancy test using refined version of Draize scoring system on rabbits, c) Possible effect on local tissues and reproductive performance in female rats after fourteen daily single dose application, d) PCNA staining- to evaluate the effect of CAD on vaginal tissue proliferation, e) TUNEL assay- to examine its ability to induce in situ apoptosis in the vaginal tissue sections of the treated animals, and f) Microbicidal activity- to explore the effect of CAD on the growth of Lactobacillus acidophilus and Candida albicans.Results
In vitro irritation studies on rabbit erythrocytes revealed the hemolytic index of CAD to be 8.2 mg/ml. The dermal irritation test showed it to be a non-irritant even at higher doses. Intra vaginal application of CAD in rat vagina for 14 consecutive days caused slight reversible inflammation on vaginal epithelial cells at doses as high as 82 mg/ml. However, at this dose level it neither had any adverse effect on vaginal tissue proliferation nor did it cause in situ apoptosis as evident from PCNA staining and TUNEL assay. Fertility and fecundity were restored 4-15 days after withdrawal of CAD application. At dose level 10 times that of its spermicidal MEC (minimum effective concentration), CAD did not block the growth of Lactobacillus, although the size of individual colony was marginally reduced. However, growth of the pathogenic fungus Candida albicans was completely inhibited with 20 mg/ml of CAD.Conclusion
The overall result evolved from the study strengthens the candidature of CAD as a safe microbicidal spermicide. It is almost non-irritant to rabbit skin and rat vaginal tissues at doses 10 fold higher than its hemolytic index. The effect of CAD on Lactobacillus culture was not highly encouraging but it prevented the growth of the fungal pathogen Candida albicans at 20 mg/ml of CAD. 相似文献955.
The synthesis of a photo-triggered biocompatible drug delivery system on the basis of coumarin-functionalized block copolymers is reported. The coumarin-functionalized block copolymers poly(ethylene oxide)-b-poly(n-butyl methacrylate-co-4-methyl-[7-(methacryloyl)oxyethyloxy]coumarin)) (PEO-b-P(BMA- co-CMA)) were synthesized via atom transfer radical polymerization (ATRP). The micelle-drug conjugates were made by covalent bonding of anticancer drug 5-fluorouracil (5-FU) to the coumarin under UV irradiation at wavelength >310 nm. These micelle-drug conjugates possessed spherical morphology with diameters of 70 nm from TEM images. In vitro drug release experiments showed the controlled release of anticancer drug 5-FU from the micelle-drug conjugates under UV irradiation (254 nm). These micelle-drug conjugates also showed excellent biocompatibility by the in vitro cytotoxicity experiments. The results suggest that these micelle-drug conjugates could be a promising candidate for the delivery of anticancer agents with low side effects on normal cells and excellent therapeutic efficacy to cancer cells. 相似文献
956.
Lee J Jiang W Qiao Y Cho YI Woo MO Chin JH Kwon SW Hong SS Choi IY Koh HJ 《Proteomics》2011,11(3):455-468
To survey protein expression patterns in the reduced culm number (RCN) rice, a comparative shotgun proteomic analysis was conducted. For large-scale protein identification, multidimensional protein identification technology (MudPIT) coupled with pre-fractionation of plant shoot proteins led to the identification of 3004 non-redundant rice proteins. By statistically comparing relative amounts of 1353 reproducibly identified proteins between the RCN rice and the wild-type rice, 44 differentially expressed proteins were detected, where 42 proteins were increased and 2 proteins were decreased in the RCN rice. These proteins appear to have roles in glycolysis, trichloroacetic acid cycle, secondary metabolism, nutrient recycling, and nucleotide metabolism and repair. Consequently, we hypothesized that the RCN rice might fail to maintain sugar nutrient homeostasis. This was confirmed with the observation that the sucrose concentration was increased significantly in the RCN rice compared with the wild-type rice. Also, the RCN rice showed a hypersensitive response to exogenous sucrose treatment. 相似文献
957.
Zhou J Zeng P Cheng ZH Liu J Wang FQ Qian RJ 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(23):2304-2310
A simple and solvent-minimized sample preparation technique based on two-phase hollow fiber liquid phase microextraction has been developed and used to quantify the osthole in cerebral ischemia reperfusion rat plasma following oral administration. The analysis was performed by reversed phase high performance liquid chromatography with fluorescence detection. Extraction conditions such as solvent identity, agitation rate, salt concentration, extraction time, and length of the hollow fiber were optimized. Under the optimized conditions, the linear range of osthole in rat plasma was 5-500 ng mL(-1) (r(2) = 0.9997). The limit of detection (LOD) was 2 ng mL(-1) (S/N = 3) with limit of quantification (LOQ) being 5 ng mL(-1). The validated method has been successfully applied for pharmacokinetic studies of osthole from cerebral ischemia reperfusion rat plasma after oral administration. 相似文献
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