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New approaches in the treatment of skeletal defects may benefit from the use of soluble biological factors. We previously standardized a derivative of bovine colostrum (SBCD), deprived of casein and fat and rich in cytokines. In the present study, we tested its possible use as an adjuvant in bone healing. SBCD contained factors involved in stromal cell stimulation and differentiation and induced cytokine production from stimulated mesenchymal stem cells (MSCs). In vitro, SBCD promoted proliferation, migration and, in association with osteogenic factors, osteogenic differentiation of osteoblastic and MSCs. In in vivo experiments of subcutaneous Matrigel injection in mice, SBCD plus hydroxyapatite, but not hydroxyapatite nor SBCD alone, induced recruitment of macrophages and stromal cells. After 60?days, plugs containing SBCD and hydroxyapatite were densely calcified and diffusely positive for osteocalcin, supporting the occurrence of an early osteogenic process. These results indicate that SBCD is a rich source of factors with osteoinductive properties.  相似文献   
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Abstract

The first unambiguous documentation of hybridism in the genus Doronicum (Senecioneae – Asteraceae) is reported. All our morphological, karyological and molecular data concur to indicate that Doronicum × minutilloi Peruzzi hybr. nov. (2n = 60) is a hybrid growing in Monti Aurunci (Central Italy), originated from the spontaneous crossing D. orientale Hoffm. (2n = 60) × D. columnae Ten. (2n = 60). This new hybrid shows a slightly higher morphological, karyotypic and ribotypic affinity with D. columnae, but shares a trnL-trnF IGS haplotype with D. orientale, and co-occurs with the latter species only; it has reduced fertility and a high potential for vegetative propagation through rhizome fragmentation. Our results led us to suspect in fieri homoploid hybrid speciation.  相似文献   
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Pulsatile flow inside a moderately elastic circular conduit with a smooth expansion is studied as a model to understand the influence of wall elasticity in artery flow. The solution of the simultaneous fluid-wall evolution is evaluated by a perturbative method, where the zeroth order solution is represented by the flow in a rigid vessel; the first order correction gives the wall motion and induced flow modification without the need to solve the difficult coupled problem. Such an approach essentially assumes a locally infinite celerity, therefore it represent a good approximation for the fluid-wall interaction in sites of limited extent (branches, stenosis, aneurism, etc.), which include typical situations associated with vascular diseases. The problem is solved numerically in the axisymmetric approximation; the influence of wall elasticity on the flow and on the unsteady wall shear stress is studied in correspondence of parameters taken from realistic artery flow. Attention is posed to the role of phase difference between the incoming pressure and flow pulses.  相似文献   
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A conceptual framework is developed and used for improving the livelihood of Sub-Saharan communities faced with multiple stresses resulting from adverse environments, vector-transmitted diseases, and limited food. Ecosocial systems are the units for management. The accumulation of ecological, economic, and social capital is the objective of management, the reduction of maintenance costs is the key strategy, and technologies must satisfy ecological, economic, and social criteria. Interacting social system components are communities, facilitators, scientists, and political as well as administrative organizations. An adaptive approach to management allows flexibility in human and financial resource allocation and results in changes in knowledge and efficacy of management operations. The implementation strategy at two sites in Ethiopia relies on a two-stage procedure. In Stage 1, human and cattle health management set the conditions for development. In Stage 2, the ecosocial system is kept on a trajectory to enhanced ecological, economic, and social capital. In each stage, the assignment of responsibilities leads to four implementation phases. In Stage 1, successful precision targeting of tsetse and drug-based Trypanosoma spp. control increased the economic and social capital at the Luke site in southwestern Ethiopia but threatened the ecological capital because of overstocking and land degradation. In Stage 2, a women’s group living in the outskirts of Addis Ababa (Ethiopia) transformed barren land into a horticultural enterprise to enhance ecosystem service provision, including production of horticultural goods, and increase soil fertility expressed by nutrients and water availability. This article reviews concepts on human livelihood improvement in Sub-Saharan Africa and identifies principles that became important during project execution.  相似文献   
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Summary The sporophyte ultrastructure ofTortula muralis Hedw. has been investigated by scanning and transmission electron microscopy. We have observed the twistings on the surface of the seta, the stomata in the lower part of the capsule and the disposition of cortical, conductive and parenchyma cells in the transversal and longitudinal sections of the seta. Moreover, in transection, the calyptra cells are thick-walled and present structures like tips in front of the epidermis cells of the capsule. Possible meanings of these morphological observations are discussed.  相似文献   
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Adriamycin, a new antitumour antibiotic of the anthracycline group with a structural formula very similar to daunorubicin, has proved to have potent tumour-growth-inhibiting properties, and to be particularly effective in childhood malignancies. Though adriamycin produces a higher percentage of side-effects than daunorubicin—namely, stomatitis and alopecia—a lower dosage may be used for therapy.  相似文献   
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Reactive oxygen species (ROS)-induced oxidative stress increases in skeletal muscle with aging and decreases the viability of implanted cells. Type 1 insulin-like growth factor (IGF-1) promotes the survival of skeletal muscle cells under oxidative stress. It is unknown whether IGF-1 protects muscle-derived stem cells (MDSCs) from oxidative stress. In this study, we genetically engineered rat MDSCs to overexpress IGF-1 and determined cell viability, apoptosis, and VEGF secretion under oxidative stress. Overexpression of IGF-1 prevented MDSCs from H2O2-induced caspase-dependent apoptotic cell death by upregulating the PI3K/AKT pathway, accompanied with an increase of NF-κB, p-NF-κB, Bcl-2, and VEGF, as well as a decrease of Bax. In contrast, pre-administration of picropodophyllinb, wortmannin, 1L-6-hydroxymethyl-chiro-inositol-2-((R)-2-O-methyl-3-O-octadecylcarbonate), or pyrrolidine-dithiocarbamate, specific inhibitors of IGF-1R, PI3K, AKT, and NF-κB, respectively, followed by treatment with H2O2, resulted in cell death of MDSCs. Our data indicated that IGF-1 suppresses apoptosis and enhances the paracrine function of MDSCs under oxidative stress via enhancing IGF-1R/PI3K/AKT signaling. Thus, IGF-1 gene-modified MDSCs present a potential application in the treatment of muscle wasting, such as urethra intrinsic sphincter deficiency.  相似文献   
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