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101.
We report that the monolayer phase diagram for binary mixtures of dimyristoylphosphatidylethanolamine (DMPE) and dihydrocholesterol (DChol) is largely unchanged when each phospholipid molecule is replaced by two myristic acid (MA) molecules or various mixtures of the lysophospholipid and myristic acid. The corresponding phase diagrams all show the formation of "condensed complexes" of DChol and lipid. The condensed complex stoichiometry is thus largely determined by the C14 fatty acid acyl chains, in this case about 4-4.6 per DChol molecule. 相似文献
102.
103.
104.
Rivera OJ Song CS Centonze VE Lechleiter JD Chatterjee B Roy AK 《Molecular endocrinology (Baltimore, Md.)》2003,17(1):128-140
The dynamic interaction between the androgen receptor (AR) and steroid receptor coactivator-1 (SRC-1) was explored in living cells expressing chimeric forms of the receptor and the coactivator containing two spectral variants of jellyfish fluorescent protein. Laser scanning confocal imaging of transfected cells expressing fluorescently labeled SRC-1 revealed that in an unsynchronized cell population, the coactivator is distributed in approximately 40% cells as nuclear bodies of 0.2-1.0 microm in diameter. Immunostaining of cyan fluorescent protein-labeled SRC-1 (CFP-SRC1)-expressing cells with antibody to promyelocytic leukemia (PML) protein showed significant overlap of the CFP fluorescence with the antibody stain. Cotransfection of cells with a plasmid expressing the CFP conjugate of Sp100 (another marker protein for the PML nuclear body) also showed colocalization of the yellow fluorescent protein (YFP)-SRC1 containing nuclear foci with the PML bodies in living cells. Analysis of the three-dimensional structure revealed that the PML bodies are round to elliptical in shape with multiple satellite bodies on their surface. Some of these satellite bodies contain the SRC-1. Activation and nuclear import of CFP-AR by the agonistic ligand 5alpha-dihydrotestosterone, but not by the antagonist casodex, transferred YFP-SRC1 from the PML bodies to an interlacing filamentous structure. In a single living cell, agonist-activated AR caused a time-dependent movement of YFP-SRC1 from the PML bodies to this filamentous structure. Additionally, coexpression of a constitutively active mutant of AR (AR-deltaligand binding domain) also displaced YFP-SRC1 from the PML bodies to this intranuclear filamentous structure. The fluorescence recovery after photobleaching approach was used to examine changes in the kinetics of movement of YFP-SRC1 during its mobilization from the PML bodies to the intranuclear filamentous structure by the agonist-activated AR. Results of the relative half-times (t(1/2)) of replacement of YFP-SRC1 within the photobleached region of a single PML body from its surrounding nuclear space supported the conclusion that SRC-1 is actively transported from the PML bodies to the intranuclear filamentous structure by the ligand-activated AR. This observation also suggests an interaction between AR and SRC-1 before its binding to the target gene. The PML bodies have been implicated as a cross-road for multiple regulatory pathways that control cell proliferation, cellular senescence, and apoptosis. Our present results along with other recent reports expand the role of this subnuclear structure to include the regulation of steroid hormone action. 相似文献
105.
AIM: To determine whether maturation and subsequent blastocyst development of in vitro matured oocytes can be improved by in vivo follicle stimulating hormone (FSH) or human chorionic gonadotrophin (hCG) priming, using a mouse model. EXPERIMENTAL DESIGN: Five groups of oocytes were used: in vivo control, in vitro matured (IVM) control, IVM after 24 h in vivo priming with FSH, IVM after 48 h in vivo priming with FSH and IVM after 16 h in vivo priming with hCG. In vitro fertilization (IVF) was performed on all groups.Oocyte maturation, fertilization, blastocyst development rates and blastocyst cell numbers were assessed for all groups. RESULTS: Significant improvement in oocyte maturation was observed in the two FSH priming groups compared with the IVM control group (P<0.005 and P<0.001, respectively). There were no significant differences in fertilization between all five groups. Blastocyst development was significantly higher in the in vivo control compared to the IVM groups (P<0.001). No significant differences were observed in blastocyst cell numbers among all five groups. CONCLUSIONS: While FSH priming improves the maturation rate of IVM oocytes, FSH or hCG priming does not improve development to the blastocyst stage. 相似文献
106.
Complete archaeal genomes were probed for the presence of long (> or = 25 bp) oligonucleotide repeats (words). We detected the presence of many words distributed in tandem with narrow ranges of periodicity (i.e., spacer length between repeats). Similar words were not identified in genomes of non-archaeal species, namely Escherichia coli, Bacillus subtilis, Haemophilus influenzae, Mycoplasma genitalium and Mycoplasma pneumoniae. BLAST similarity searches against the GenBank nucleotide sequence database revealed that these words were archaeal species-specific, indicating that they are of a signature character. Sequence analysis and genome viewing tools showed these repeats to be restricted to non-coding regions. Thus, archaea appear to possess a non-coding genomic signature that is absent in bacterial species. The identification of a species-specific genomic signature would be of great value to archaeal genome mapping, evolutionary studies and analyses of genome complexity. 相似文献
107.
108.
Rajakrishnan V Jayadeep A Arun OS Sudhakaran PR Menon VP 《The Journal of nutritional biochemistry》2000,11(10):509-514
The present study was undertaken to evaluate the potential role of curcumin, the antioxidant principal from Curcuma longa Linn., and the sulphur-containing amino acid N-acetylcysteine against ethanol-induced changes in the levels of prostanoids. Biochemical assessment of liver damage was done by measuring the activities of serum enzymes (i.e., aspartate transaminase and alkaline phosphatase), which were significantly increased in rats fed ethanol, whereas the elevated levels of these enzymes were decreased after curcumin and N-acetylcysteine treatment to rats fed ethanol. We observed a significant increase in the levels of prostaglandins E(1), E(2), F(2alpha), and D(2) in liver, kidney, and brain. Administration of curcumin and N-acetylcysteine was shown to decrease the level of these prostanoids in the tissue studied. 相似文献
109.
We investigate the effect of migration between local populations of a single discrete-generation species living in a ring
or an array of habitats. The commonly used symmetric dispersal assumption is relaxed to include the biologically more reasonable
asymmetric dispersion. It is demonstrated analytically that density independent migration has no effect on the equilibrium
stability of individual populations. However, the positive equilibrium may be destabilizing if the migration is density dependent
in such a way that it increases with increasing population density at the source patch. 相似文献
110.
A sexually dimorphic distribution of galanin in the preoptic region of the molly and goldfish has previously been demonstrated. Females of these species lack galanin-immunoreactive perikarya in the preoptic nucleus. In contrast, we have found, in female red salmon, galanin-immunoreactive neurons in the magnocellular preoptic nucleus, located far lateral to the preoptic recess, whereas many immunoreactive fibers are present in the preoptic area in both genders. In addition, many immunoreactive neurons have been seen in the nucleus preopticus periventricularis and nucleus lateralis tuberis, also in both sexes. These findings support the notion that galanin may play a gender-specific role in red salmon. 相似文献