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121.
Katarzyna Sękiewicz Krystyna Boratyńska Magda Bou Dagher-Kharrat Tolga Ok Adam Boratyński 《分类学与生物多样性》2013,11(5):494-508
We investigated the interspecific morphological relationships of two related Mediterranean Cupressus taxa and the possible geographic differentiation of Eastern Mediterranean C. sempervirens using morphometric analysis. A total of 446 individuals, representing eight C. atlantica (Morocco) and 10 C. sempervirens (Greece, Turkey and Lebanon) populations were examined. The 17 morphological characters of cone, seed and shoot with leaves were measured and analysed statistically. Significant morphological differences between C. atlantica and C. sempervirens were detected for the majority of analysed characters. For C. sempervirens, significant differences were also detected and these were related to its three regions of origin, the Greek Islands, Taurus Mts and Lebanon Mts. Multivariate analyses did not indicate a clear geographic pattern of differentiation in C. sempervirens populations. A relatively low level of phenotypic differentiation was detected between populations originating from the Greek Islands and Taurus Mts. We also observed a moderate multivariate differentiation between the Lebanese and remaining C. sempervirens populations. Phenotypic differentiation detected in the Asian part of the C. sempervirens range reflects patterns of differentiation similar to those described for other taxa occurring in the Taurus and Lebanon Mts. 相似文献
122.
María del Carmen Martínez-Ballesta Germán Bou Micaela Carvajal 《Phytochemistry Reviews》2014,13(3):573-586
Aquaporins (AQPs) are integral membrane proteins that serve as selective pores through which water and small solutes cross the plasma membranes of many human tissue and cell types. They have been identified in epithelia and endothelia involved in fluid transport, such as kidney tubules and glandular epithelia, glial cells, epidermis, and adipocytes. The pathophysiological roles of these proteins and the primary and secondary involvement of AQPs are becoming apparent in diverse clinical disorders, from diabetes insipidus to various forms of edema. The advanced understanding of aquaporin biology, from the structural determinants of channel permeability to the assignment of their physiological function in different organs, will allow the use of AQPs as targets for the therapy of a wide array of diseases. In this review, the mode of action of clinically-effective plant formulae on human AQPs-related diseases at the molecular, cellular, and organism levels is explored. The use of pharmacological plant-derived compounds as a possible strategy in the therapy of diseases related to altered water homeostasis should stimulate debate and further research objectives. 相似文献
123.
The gene encoding the TPL N-terminal domain (N-TPL), fused with a His6-tag, was cloned and expressed in Pichia pastoris, under the control of the glyceraldehyde-3-phosphate dehydrogenase (GAP) constitutive promoter. The recombinant protein was successfully expressed and secreted with an expression level of 5 mg/l of culture medium after 2 days of culture. The N-TPL was purified through a one-step Ni-NTA affinity column with a purification factor of approximately 23-fold. The purified N-TPL, with a molecular mass of 35 kDa, had a specific activity of 70 U/mg on tributyrin. Surprisingly, this domain was able to hydrolyse long chain TG with a specific activity of 11 U/mg using olive oil as substrate. This result was confirmed by TLC analysis showing that the N-TPL was able to hydrolyse insoluble substrates as olive oil. N-TPL was unstable at temperatures over 37°C and lost 70% of its activity at acid pH, after 5 min of incubation. The N-TPL exhibited non linear kinetics, indicating its rapid denaturation at the tributyrin–water interface. Colipase increased the N-TPL stability at the lipid-water interface, so the TPL N-terminal domain probably formed functional interactions with colipase despite the absence of the C-terminal domain. 相似文献
124.
Porcine Pluripotent Stem Cells Derived from IVF Embryos Contribute to Chimeric Development In Vivo 总被引:1,自引:0,他引:1
Binghua Xue Yan Li Yilong He Renyue Wei Ruizhen Sun Zhi Yin Gerelchimeg Bou Zhonghua Liu 《PloS one》2016,11(3)
Although the pig is considered an important model of human disease and an ideal animal for the preclinical testing of cell transplantation, the utility of this model has been hampered by a lack of genuine porcine embryonic stem cells. Here, we derived a porcine pluripotent stem cell (pPSC) line from day 5.5 blastocysts in a newly developed culture system based on MXV medium and a 5% oxygen atmosphere. The pPSCs had been passaged more than 75 times over two years, and the morphology of the colony was similar to that of human embryonic stem cells. Characterization and assessment showed that the pPSCs were alkaline phosphatase (AKP) positive, possessed normal karyotypes and expressed classic pluripotent markers, including OCT4, SOX2 and NANOG. In vitro differentiation through embryonic body formation and in vivo differentiation via teratoma formation in nude mice demonstrated that the pPSCs could differentiate into cells of the three germ layers. The pPSCs transfected with fuw-DsRed (pPSC-FDs) could be passaged with a stable expression of both DsRed and pluripotent markers. Notably, when pPSC-FDs were used as donor cells for somatic nuclear transfer, 11.52% of the reconstructed embryos developed into blastocysts, which was not significantly different from that of the reconstructed embryos derived from porcine embryonic fibroblasts. When pPSC-FDs were injected into day 4.5 blastocysts, they became involved in the in vitro embryonic development and contributed to the viscera of foetuses at day 50 of pregnancy as well as the developed placenta after the chimeric blastocysts were transferred into recipients. These findings indicated that the pPSCs were porcine pluripotent cells; that this would be a useful cell line for porcine genetic engineering and a valuable cell line for clarifying the molecular mechanism of pluripotency regulation in pigs. 相似文献
125.
We studied morphological variation in two closely related and ecologically similar species of mice of the genus Peromyscus, the deer mouse (P. maniculatus) and white-footed mouse (P. leucopus), over the last 50 years in Southern Quebec. We found that contemporary populations of the two species are distinct in morphology and interpret this differentiation as a reflection of resource partitioning, a mechanism favouring their local coexistence. While there was no size trend, geographic or temporal, both species displayed a concomitant change in the shape of their skull over the last 50 years, although this change was much more apparent in the white-footed mouse. As a result, the two species diverged over time and became more distinct in their morphology. The observed changes in morphology are large given the short time scale. During this period, there was also a shift in abundance of the two species in Southern Quebec, consistent with the northern displacement of the range of the white-footed mouse in the last 15 years. Our study thus reports the changes in morphology of two co-occurring mammal species that were accompanied by changes in distribution and local abundance, potentially in response to rapid climate change. 相似文献
126.
Boué J Blanpied C Brousset P Vergnolle N Dietrich G 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(9):5078-5084
Pain is an inherent component of inflammation often accompanying immune response. A large spectrum of molecules released within the inflamed tissue induces pain by stimulating primary afferent neurons in situ. Activity of primary sensitive fibers can be counteracted by local opioid release by leukocytes. In this study, we investigated the endogenous regulation of CFA-induced inflammatory pain in the context of adaptive T cell immune response. The nociceptive response to mechanical stimuli was studied using von Frey filaments in mice immunized with OVA in CFA. The nociceptive response of nude versus wild-type mice was dramatically increased, demonstrating T cell deficiency associated with increased pain sensitivity. Based on adoptive transfer experiments of OVA-specific CD4(+) T lymphocytes into nude mice, we show that Ag-specific activated, but not resting T lymphocytes are responsible for the spontaneous relief of inflammation-induced pain following Ag challenge. The analgesia was dependent on opioid release by Ag-primed CD4(+) T lymphocytes at the inflammatory site. Indeed, T cell-mediated analgesia was inhibited by local injection of an opioid receptor antagonist, unable to cross the blood-brain barrier. Notably, we found opioid precursor mRNA to be >7-fold increased in Ag-specific activated CD4(+) T lymphocytes, as compared with resting T lymphocytes in vivo. Taken together, our results show that CD4(+) T lymphocytes acquire antinociceptive effector properties when specifically primed by Ag and point out analgesia as a property linked to the effector phase of adaptive T cell response. 相似文献
127.
128.
Furimsky A Vuong N Xu H Kumarathasan P Xu M Weerachatyanukul W Bou Khalil M Kates M Tanphaichitr N 《Biology of reproduction》2005,72(3):574-583
Although Percoll gradient centrifugation has been used routinely to prepare motile human sperm, its use in preparing motile mouse sperm has been limited. Here, we showed that Percoll gradient-centrifuged (PGC) capacitated mouse sperm had markedly higher fertilizing ability (sperm-zona pellucida [ZP] binding and in vitro fertilization) than washed capacitated mouse sperm. We also showed that the lipid profiles of PGC capacitated sperm and washed capacitated sperm differed significantly. The PGC sperm had much lower contents of cholesterol and phospholipids. This resulted in relative enrichment of male germ cell-specific sulfogalactosylglycerolipid (SGG), a ZP-binding ligand, in PGC capacitated sperm, and this would explain, in part, their increased ZP-binding ability compared with that of washed capacitated sperm. Analyses of phospholipid fatty acyl chains revealed that PGC capacitated sperm were enriched in phosphatidylcholine (PC) molecular species containing highly unsaturated fatty acids (HUFAs), with docosahexaenoic acid (DHA; C22: 6n-3) being the predominant HUFA (42% of total hydrocarbon chains of PC). In contrast, the level of PC-HUFAs comprising arachidonic acid (20:4n-6), docosapentaenoic acid (C22:5n-6), and DHA in washed capacitated sperm was only 27%. Having the highest unsaturation degree among all HUFAs in PC, DHA would enhance membrane fluidity to the uppermost. Therefore, membranes of PGC capacitated sperm would undergo fertilization-related fusion events at higher rates than washed capacitated sperm. These results suggested that PGC mouse sperm should be used in fertilization experiments and that SGG and DHA should be considered to be important biomarkers for sperm fertilizing ability. 相似文献
129.
130.