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101.
Suski M Olszanecki R Madej J Totoń-Żurańska J Niepsuj A Jawień J Bujak-Giżycka B Okoń K Korbut R 《Journal of Proteomics》2011,74(6):887-893
The involvement of both apolipoprotein E (apoE) and mitochondria in lipid metabolism is widely recognized, however there is surprisingly scarce data about the putative mitochondrial action(s) of this protein. The aim of the study was to screen the alterations in liver mitochondrial proteome caused by apoE deficiency. We applied 2DE-LC-MS/MS methodology to investigate the changes in liver mitochondrial protein expression in 6-months old apoE(-/-) mice as compared to C57BL/6J controls. ApoE(-/-), but not C57BL/6J mice developed visible atherosclerotic changes in aorta and mild, diffuse steatosis of the liver. Collectively, 18 differentially expressed proteins were identified in mitochondria, related to apoptosis, antioxidant and detoxifying mechanisms of mitochondria, as well as lipid metabolism and transport. In conclusion, differential proteomic approach revealed several lines of proteomic evidence that mitochondrial function in the liver of apoE(-/-) mice could be altered as a result of overlapping of pathological and compensatory changes in expression of proteins. 相似文献
102.
103.
Beata Olas Joanna Kołodziejczyk-Czepas Barbara Wachowicz Dariusz Jędrejek Anna Stochmal Wiesław Oleszek 《Central European Journal of Biology》2011,6(6):990-996
Humulus lupulus (Cannabaceae) is well known throughout the world as a raw material in the brewing industry. The antioxidative action of hop cones is poorly
understood, therefore the aim of our present study was to investigate in vitro changes in human plasma induced by peroxynitrite in the presence of the highly purified extract from hop cones (Humulus lupulus). The aim of our study was also to explain the effect of the extract from hop cones on coagulation activity of human plasma
treated with peroxynitrite. The action of the extract from hop cones was compared with the properties of a well-characterized
commercial monomeric polyphenol — resveratrol (3,4′,5-trihydroxystilbene). The tested plant extract, like resveratrol, significantly
inhibited protein carbonylation and nitration in plasma treated with ONOO−(0.1 mM). The extract from hop cones, like resveratrol, also caused a distinct reduction of plasma lipid peroxidation induced
by ONOO−. Moreover, the tested extract modulated the coagulation properties of plasma treated with peroxynitrite. It seems that antioxidative
activities of the highly purified extract from hop cones may be responsible for its medicinal properties. 相似文献
104.
The chemokine receptor CXCR3, which was shown to take part in many inflammatory processes, is considered as a Th1 specific marker. Here, we show in a mouse model that CXCR3 expressing CD4(+) cells preferentially migrate to the peritoneal cavity under steady-state conditions. The peritoneal cavity milieu leads to an up-regulated expression of CXCR3. However, blocking of known ligands of this chemokine receptor did not alter the preferential migration. The peritoneal cavity environment also results in an increased percentage of memory cells producing cytokines. Up-regulation of IFNγ production occurs mostly in CXCR3(+) cells considered as Th1, whereas the up-regulation of IL-4 affects mostly in CXCR3(-) cells which are considered as Th2. We conclude that the peritoneal cavity does not change the Th-lineage of the cells, but that domination of this anatomic niche by Th1 cells rather results from preferential migration to this compartment. 相似文献
105.
Usarek E Gajewska B Kaźmierczak B Kuźma M Dziewulska D Barańczyk-Kuźma A 《Neurochemical research》2005,30(8):1003-1007
The expression of glutathione S-transferase pi (GST pi), an enzyme responsible for inactivation of a large variety of toxic compounds was studied in spinal
cord, motor and sensory brain cortex obtained from patients who died in the course of amyotrophic lateral sclerosis (ALS).
The studies were performed on formalin-fixed, paraffin-embedded (FFPE) and freshly frozen tissues. The method of RNA isolation
from FFPE was modified. A significant decrease of GST pi-mRNA expression was found in cervical spinal cord and motor brain
cortex of ALS subjects comparing to analogue control tissues (P < 0.01), as well as in motor cortex of ALS subjects comparing to their sensory cortex (P < 0.05). In spinal cords the decrease in GST pi-mRNA expression was accompanied by a decrease of GST pi protein level. Results
indicated lowered GST pi expression on both mRNA and protein levels in the regions of nervous system affected by ALS. The
non-properly inactivated by GST toxic electrophiles and organic peroxides may thus contribute to motor neurons damage. 相似文献
106.
Paluchowska MH Bugno R Bojarski AJ Charakchieva-Minol S Duszyńska B Tatarczyńska E Kłodzińska A Stachowicz K Chojnacka-Wójcik E 《Bioorganic & medicinal chemistry》2005,13(4):1195-1200
Novel, flexible arylpiperazine gepirone analogs (1a-3a) with a mixed 5-HT1A/5-HT2A receptor profile, low D2 receptor affinity, and agonistic (2a) or partial agonistic (1a, 3a) activity toward 5-HT1A receptor sites were synthesized. Their conformationally restricted counterparts (1b-3b) were selective 5-HT1A ligands (over 5-HT2A and D2 receptors), which turned out to be agonists (2b, 3b), or partial agonist (1b) of 5-HT1A receptors. 相似文献
107.
Olsson M Madsen T Uller T Wapstra E Ujvari B 《Evolution; international journal of organic evolution》2005,59(1):221-225
Sex allocation theory predicts that parents should bias their reproductive investments toward the offspring sex generating the greatest fitness return. When females are the heterogametic sex (e.g., ZW in butterflies, some lizards, and birds), production of daughters is associated with an increased risk of offspring inviability due to the expression of paternal, detrimental recessives on the Z chromosome. Thus, daughters should primarily be produced when mating with partners of high genetic quality. When female sand lizards (Lacerta agilis) mate with genetically superior males, exhibiting high MHC Class I polymorphism, offspring sex ratios are biased towards daughters, possibly due to recruitment of more Z-carrying oocytes when females have assessed the genetic quality of their partners. If our study has general applicability across taxa, it predicts taxon-specific sex allocation effects depending on which sex is the heterogametic one. 相似文献
108.
The present study was undertaken to elucidate the role of OT in myometrial contractility in sows. Spontaneous and OT-stimulated contractions of the inner circular (CM) and outer longitudinal (LM) layers isolated from cyclic (Days 14-16) and early pregnant (Days 14-16) sows were examined in six cyclic and six pregnant sows. In addition, the role of P(4) in the modulation of OT-induced uterine contractions was investigated. The contractile activity of the LM and CM layers was recorded in a tissue chamber filled with Krebs-Ringer solution. Myometrial contractility was expressed as area under the contractility curve (AUC) and frequency of contractions. Myometrial longitudinal and circular muscles exhibited spontaneous contractility in sows during both luteolysis and early-pregnancy. The mean AUC was higher (p<0.05) in the LM layer compared to the CM layer in both cyclic and pregnant animals. In addition, pregnant sows were characterized by higher AUC in both LM and CM layers in comparison to cyclic sows. The CM layer was unresponsive to examined treatments. Oxytocin (1-3x10(-8) and 1-3x10(-7)M) increased the AUC and frequency of contractions of the LM layer in both examined animal groups, being more effective during luteolysis (p<0.001) than early pregnancy (p<0.01). Response of the LM layer to OT appeared to be clearly related to the initial spontaneous level of contractility. This response to OT was inhibited (p<0.05) in the presence of OT antagonist (10(-6)M). Moreover, in pregnant sows, OT-stimulated contractile activity of myometrium was inhibited (p<0.05) by P(4) (10(-5)M). In conclusion, OT receptors present in myometrial cells (especially in the LM layer) are involved in the regulation of contractile activity of porcine myometrium during luteolysis and early-pregnancy. In addition, progesterone appears to be involved in this regulation. 相似文献
109.
110.
Olsson M Madsen T Ujvari B Wapstra E 《Evolution; international journal of organic evolution》2004,58(4):906-909
We demonstrate that extending copulation enhances probability of paternity in sand lizards and that determinants of copulation duration depend on a males' mating order (first or second). First males, with no information on presence of rivals, extend copulation when mating with a more fecund female. Second males, however, adjust copula duration in relation to a first male's relatedness with his female, which there is reason to believe can be deduced from the MHC-related odor of the copulatory plug. Male-female relatedness negatively influences a male's probability of paternity, and when second males are in a favored role (i.e., the first male is the one more closely related to the female), second males transfer larger ejaculates, resulting in higher probability of paternity. This result corroborates predictions from recent theoretical models on sperm expenditure theory incorporating cryptic female choice and sexual conflict. More specifically, the results conform to a "random roles" model, which depicts males as being favored by some females and disfavored by others, but not to a "constant-type" model, in which a male is either favored or disfavored uniformly by all females in a population. 相似文献