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991.
Seokhoon Park Christof Rampitsch Gavin D Humphreys Belay T Ayele 《Plant signaling & behavior》2013,8(12)
Seed dormancy is an important trait in wheat (Trticum aestivum L.) and it can be released by germination-stimulating treatments such as after-ripening. Previously, we identified proteins specifically associated with after-ripening mediated developmental switches of wheat seeds from the state of dormancy to germination. Here, we report seed proteins that exhibited imbibition induced co-regulation in both dormant and after-ripened seeds of wheat, suggesting that the expression of these specific proteins/protein isoforms is not associated with the maintenance or release of seed dormancy in wheat. 相似文献
992.
Hai Chun Liu Hua Zhao Jian Chen Wen Liang Wu Hong Liang Wang Gang Jun Jiao Yun Zhen Chen 《Journal of molecular histology》2013,44(5):535-544
Decreased levels of serum insulin-like growth factor-1 (IGF-1) have been proven to cause osteoporosis. Gene transfer of IGF-1 offers an attractive technology to treat skeletal metabolic disorders including osteoporosis, but the viral vectors are limited by their high antigenicity and immune response. Our purpose was to investigate the expression of a non-invasive vector, recombinant plasmid enhanced green fluorescent protein-N1 (pEGFP-N1) that transferred IGF-1 gene into ovariectomized (OVX) rats in vivo and evaluate the effect of this therapy on osteoporosis. OVX or sham operations were performed in 60 female, 7-month-old unmated SD rats. 12 weeks after OVX operation, the vectors were transfected to the 10-month-old rats and experimental data were detected from 48 h to 7 week after transfection. Our results showed that remarkable expression of fluorescence and serum IGF-1 was observed in the rats transfected by recombinant plasmids, indicating that IGF-1 gene was successfully transferred to OVX rats by injecting the vector through hydrodynamic method via the tail vein. The bone metabolism index including serum alkaline phosphatase, the histomorphometric parameters of lumbar vertebra including trabecular area percentage, trabecular thickness, trabecular number and trabecular separation, and the bone mineral density (BMD) and biomechanical parameters of lumbar vertebra including BMD, maximum condensing force, crushing strength in OVX rats transfected by pEGFP-N1-IGF-1 were improved remarkably compared with OVX+pEGFP-N1 rats, indicating that the transfection of recombinant plasmid pEGFP-N1-IGF-1 played a significant role in alleviating osteoporosis in rats induced by OVX. This encouraged a potential approach of IGF-1 gene therapy to the treatment of osteoporosis. 相似文献
993.
Su-Jin Park Hyun-Sook Bae Young-Sik Cho Soon-Ryun Lim Seung-Ae Kang Joo-Cheol Park 《Journal of molecular histology》2013,44(1):65-73
Bone remodeling, the selective deposition and resorption of bone, is an important cause of tooth eruption. During tooth eruption, reduced enamel epithelia of the enamel organ interact with follicle cells to recruit osteoclasts for bone remodeling. However, little is known about the relationship between cellular activity of reduced enamel epithelium and bone resorption during tooth eruption. The purpose of this study was to investigate the effect of apoptosis in reduced enamel epithelium on osteoclastogenesis and its implications for bone resorption. We have analyzed erupting mandibular molars in mice by TdT-mediated dUTP-biotin nick end labeling assay, tartrate-resistant acid phosphatase (TRAP) staining, and immunohistochemistry. TRAP-positive cells were detected in the osteoclasts near both the buccal and lingual sides of tooth socket at postnatal day 0 (PN0). They significantly increased until PN3 and decreased thereafter as the tooth erupted. Interestingly, apoptosis was barely detected in the reduced enamel epithelium at PN3 but clearly at PN7. A few apoptotic cells were also investigated within the dental follicle surrounding developing tooth at PN7 and PN10. We observed apoptotic osteoblast-lineage cells along the inner margin of alveolar bone facing the buccal cusp and at the base of the bony crypt at PN3 decreasing until PN10. In contrast, expression levels of bone sialoprotein increased at PN10 compared to levels at PN3. These results suggest that apoptosis of reduced enamel epithelium resulted in a reduction of osteoclast activity and of bone resorption mediated by dental follicle during tooth eruption. 相似文献
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996.
Hyun-Ju Cho Hyun-Jai Cho Ho-Jae Lee Myung-Kang Song Ji-Yun Seo Yeon-Hee Bae Ju-Young Kim Hae-Young Lee Whal Lee Bon-Kwon Koo Byung-Hee Oh Young-Bae Park Hyo-Soo Kim 《PLoS biology》2013,11(4)
Vascular calcification is an advanced feature of atherosclerosis for which no effective therapy is available. To investigate the modulation or reversal of calcification, we identified calcifying progenitor cells and investigated their calcifying/decalcifying potentials. Cells from the aortas of mice were sorted into four groups using Sca-1 and PDGFRα markers. Sca-1+ (Sca-1+/PDGFRα+ and Sca-1+/PDGFRα−) progenitor cells exhibited greater osteoblastic differentiation potentials than Sca-1− (Sca-1−/PDGFRα+ and Sca-1−/PDGFRα−) progenitor cells. Among Sca-1+ progenitor populations, Sca-1+/PDGFRα− cells possessed bidirectional differentiation potentials towards both osteoblastic and osteoclastic lineages, whereas Sca-1+/PDGFRα+ cells differentiated into an osteoblastic lineage unidirectionally. When treated with a peroxisome proliferator activated receptor γ (PPARγ) agonist, Sca-1+/PDGFRα− cells preferentially differentiated into osteoclast-like cells. Sca-1+ progenitor cells in the artery originated from the bone marrow (BM) and could be clonally expanded. Vessel-resident BM-derived Sca-1+ calcifying progenitor cells displayed nonhematopoietic, mesenchymal characteristics. To evaluate the modulation of in vivo calcification, we established models of ectopic and atherosclerotic calcification. Computed tomography indicated that Sca-1+ progenitor cells increased the volume and calcium scores of ectopic calcification. However, Sca-1+/PDGFRα− cells treated with a PPARγ agonist decreased bone formation 2-fold compared with untreated cells. Systemic infusion of Sca-1+/PDGFRα− cells into Apoe−/− mice increased the severity of calcified atherosclerotic plaques. However, Sca-1+/PDGFRα− cells in which PPARγ was activated displayed markedly decreased plaque severity. Immunofluorescent staining indicated that Sca-1+/PDGFRα− cells mainly expressed osteocalcin; however, activation of PPARγ triggered receptor activator for nuclear factor-κB (RANK) expression, indicating their bidirectional fate in vivo. These findings suggest that a subtype of BM-derived and vessel-resident progenitor cells offer a therapeutic target for the prevention of vascular calcification and that PPARγ activation may be an option to reverse calcification. 相似文献
997.
Hoon-Ki Sung Kyung-Oh Doh Joe Eun Son Jin Gyoon Park Yunui Bae Soojeong Choi Seana Mary Lunney Nelson Rebecca Cowling Kristina Nagy Iacovos P. Michael Gou Young Koh S. Lee Adamson Tony Pawson Andras Nagy 《Cell metabolism》2013,17(1):61-72
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998.
Domenico Campolo Ferdinan Widjaja Hong Xu Wei Tech Ang Etienne Burdet 《PLoS computational biology》2013,9(4)
This work introduces a coordinate-independent method to analyse movement variability of tasks performed with hand-held tools, such as a pen or a surgical scalpel. We extend the classical uncontrolled manifold (UCM) approach by exploiting the geometry of rigid body motions, used to describe tool configurations. In particular, we analyse variability during a static pointing task with a hand-held tool, where subjects are asked to keep the tool tip in steady contact with another object. In this case the tool is redundant with respect to the task, as subjects control position/orientation of the tool, i.e. 6 degrees-of-freedom (dof), to maintain the tool tip position (3dof) steady. To test the new method, subjects performed a pointing task with and without arm support. The additional dof introduced in the unsupported condition, injecting more variability into the system, represented a resource to minimise variability in the task space via coordinated motion. The results show that all of the seven subjects channeled more variability along directions not directly affecting the task (UCM), consistent with previous literature but now shown in a coordinate-independent way. Variability in the unsupported condition was only slightly larger at the endpoint but much larger in the UCM. 相似文献
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