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31.
Nuclear pore complex (NPC) is the only corridor for macromolecules exchange between nucleus and cytoplasm. NPC and its components, nucleoporins, play important role in the diverse physiological processes including macromolecule exchange, chromosome segregation, apoptosis and gene expression. Recent reports also suggest involvement of nucleoporins in carcinogenesis. Applying proteomics, we analyzed expression pattern of the NPC components in a newly established esophageal cancer cell line from Persia (Iran), the high-risk region for esophageal cancer. Our results indicate overexpression of Hsc70 and downregulation of subunit alpha type-3 of proteasome, calpain small subunit 1, and eIF5A-1. Among these proteins, Hsc70 and eIF5A-1 are in direct interaction with NPC and involved in the nucleocytoplasmic exchange. Hsc70 plays a critical role as a chaperone in the formation of a cargo–receptor complex in nucleocytoplasmic transport. On the other hand, it is an NPC-associated protein that binds to nucleoporins and contributes in recycling of the nucleocytoplasmic transport receptors in mammals and affects transport of proteins between nucleus and cytoplasm. The other nuclear pore interacting protein: eIF5A-1 binds to the several nucleoporins and participates in nucleocytoplasmic transport. Altered expression of Hsc70 and eIF5A-1 may cause defects in nucleocytoplasmic transport and play a role in esophageal carcinogenesis.  相似文献   
32.
Dental tissue-derived stem cells (DSCs) provide an easy, accessible, relatively noninvasive promising source of adult stem cells (ASCs), which brought encouraging prospective for their clinical applications. DSCs provide a perfect opportunity to apply for a patient's own ASC, which poses a low risk of immune rejection. However, problems associated with the long-term culture of stem cells, including loss of proliferation and differentiation capacities, senescence, genetic instability, and the possibility of microbial contamination, make cell banking necessary. With the rapid development of advanced cryopreservation technology, various international DSC banks have been established for both research and clinical applications around the world. However, few studies have been published that provide step-by-step guidance on DSCs isolation and banking methods. The purpose of this review is to present protocols and technical details for all steps of cryopreserved DSCs, from donor selection, isolation, cryopreservation, to characterization and quality control. Here, the emphasis is on presenting practical principles in accordance with the available valid guidelines.  相似文献   
33.
Large-scale proliferation and multi-lineage differentiation capabilities make neural stem cells (NSCs) a promising renewable source of cells for therapeutic applications. However, the practical application for neuronal cell replacement is limited by heterogeneity of NSC progeny, relatively low yield of neurons, predominance of astrocytes, poor survival of donor cells following transplantation and the potential for uncontrolled proliferation of precursor cells. To address these impediments, we have developed a method for the generation of highly enriched immature neurons from murine NSC progeny. Adaptation of the standard differentiation procedure in concert with flow cytometry selection, using scattered light and positive fluorescent light selection based on cell surface antibody binding, provided a near pure (97%) immature neuron population. Using the purified neurons, we screened a panel of growth factors and found that bone morphogenetic protein-4 (BMP-4) demonstrated a strong survival effect on the cells in vitro, and enhanced their functional maturity. This effect was maintained following transplantation into the adult mouse striatum where we observed a 2-fold increase in the survival of the implanted cells and a 3-fold increase in NeuN expression. Additionally, based on the neural-colony forming cell assay (N-CFCA), we noted a 64 fold reduction of the bona fide NSC frequency in neuronal cell population and that implanted donor cells showed no signs of excessive or uncontrolled proliferation. The ability to provide defined neural cell populations from renewable sources such as NSC may find application for cell replacement therapies in the central nervous system.  相似文献   
34.
Physiology and Molecular Biology of Plants - We explored the influence of pollination season and maturity of capsule on post-pollination capsule formation and in vitro asymbiotic seed germination,...  相似文献   
35.
36.
Venous and arterial thrombosis are conditions that have a considerable burden if left untreated. The hypoxia-induced by the occluded vessel can disrupt the circulation of any organ, the cornerstone of treating thrombosis is rapid diagnosis and appropriate treatment. Diagnosis of thrombosis may be made by using laboratory tests or imaging techniques in individuals who have clinical manifestations of a thrombotic event. The use of serum micro ribonucleic acids (RNAs) has recently been applied to the diagnosis of thrombosis. These small RNA molecules are emerging as new diagnostic markers but have had very limited applications in vascular disease. Most of the articles provided various microRNAs with different levels of accuracy. However, there remains a lack of an appropriate panel of the most specific microRNA in the literature. The purpose of the present review was to summarize the existing data on the use of microRNAs as a diagnostic biomarker for venous thrombosis.  相似文献   
37.
Peroxisome proliferator activated receptor γ, belongs to PPARs, which exerts various metabolic functions including differentiation process. To testify the importance of PPARγ in neural differentiation of mouse embryonic stem cells (mESCs), its expression level was assessed. Data revealed an elevation in expression level of PPARγ when neural precursors (NPs) are formed upon retinoic acid treatment. Thus, involvement of PPARγ in two stages of neural differentiation of mESCs, during and post-NPs formation was examined by application of its agonist and antagonist. Our results indicated that PPARγ inactivation via treatment with GW9662 during NPs formation, reduced expression of neural precursor and neural (neuronal and astrocytes) markers. However, PPARγ inactivation by antagonist treatment post-NPs formation stage only decreased the expression of mature astrocyte marker (Gfap) suggesting that inactivation of PPARγ by antagonist decreased astrocyte differentiation. Here, we have demonstrated the stage dependent role of PPARγ modulation on neural differentiation of mESCs by retinoic acid treatment for the first time.  相似文献   
38.
The major vectors of malaria in sub-Saharan Africa belong to subgenus Cellia. Yet, phylogenetic relationships and temporal diversification among African mosquito species have not been unambiguously determined. Knowledge about vector evolutionary history is crucial for correct interpretation of genetic changes identified through comparative genomics analyses. In this study, we estimated a molecular phylogeny using 49 gene sequences for the African malaria vectors An. gambiae, An. funestus, An. nili, the Asian malaria mosquito An. stephensi, and the outgroup species Culex quinquefasciatus and Aedes aegypti. To infer the phylogeny, we identified orthologous sequences uniformly distributed approximately every 5 Mb in the five chromosomal arms. The sequences were aligned and the phylogenetic trees were inferred using maximum likelihood and neighbor-joining methods. Bayesian molecular dating using a relaxed log normal model was used to infer divergence times. Trees from individual genes agreed with each other, placing An. nili as a basal clade that diversified from the studied malaria mosquito species 47.6 million years ago (mya). Other African malaria vectors originated more recently, and independently acquired traits related to vectorial capacity. The lineage leading to An. gambiae diverged 30.4 mya, while the African vector An. funestus and the Asian vector An. stephensi were the most closely related sister taxa that split 20.8 mya. These results were supported by consistently high bootstrap values in concatenated phylogenetic trees generated individually for each chromosomal arm. Genome-wide multigene phylogenetic analysis is a useful approach for discerning historic relationships among malaria vectors, providing a framework for the correct interpretation of genomic changes across species, and comprehending the evolutionary origins of this ubiquitous and deadly insect-borne disease.  相似文献   
39.
Layer-by-layer self-assembly of two polysaccharides, hyaluronan (HA) and chitosan (CH), was employed to engineer bioactive coatings for endovascular stents. A polyethyleneimine (PEI) primer layer was adsorbed on the metallic surface to initiate the sequential adsorption of the weak polyelectrolytes. The multilayer growth was monitored using a radiolabeled HA and shown to be linear as a function of the number of layers. The chemical structure, interfacial properties, and morphology of the self-assembled multilayer were investigated by time-of-flight secondary ions mass spectrometry (ToF-SIMS), contact angle measurements, and atomic force microscopy (AFM), respectively. Multilayer-coated NiTi disks presented enhanced antifouling properties, compared to unmodified NiTi disks, as demonstrated by a decrease of platelet adhesion in an in vitro assay (38% reduction; p = 0.036). An ex vivo assay on a porcine model indicated that the coating did not prevent fouling by neutrophils. To assess whether the multilayers may be exploited as in situ drug delivery systems, the nitric-oxide-donor sodium nitroprusside (SNP) was incorporated within the multilayer. SNP-doped multilayers were shown to further reduce platelet adhesion, compared to standard multilayers (40% reduction). When NiTi wires coated with a multilayer containing a fluorescently labeled HA were placed in intimate contact with the vascular wall, the polysaccharide translocated on the porcine aortic samples, as shown by confocal microscopy observation of a treated artery. The enhanced thromboresistance of the self-assembled multilayer together with the antiinflammatory and wound healing properties of hyaluronan and chitosan are expected to reduce the neointimal hyperplasia associated with stent implantation.  相似文献   
40.
Pluripotent stem cells derived from testis is a new, natural, and unlimited source for cell therapy in regenerative medicine and represent a possible alternative to replacing of all cells in the body. Here, we designed a simple co-culture system of spermatogonia cells with Sertoli cells for the generation of embryonic stem-like cells from mouse testis. The importance of our simple method will be clear when we compared it with other complex and time-consuming methods. Embryonic stem-like colonies with sharp border confirmed by real-time PCR, immunocytochemistry and flow cytometry assessments. Embryonic stem-like colonies were immunopositive for pluripotency markers. Transition of spermatogonia cells to embryonic stem-like cells was accompanied by extensive changes in gene expression. These changes included significant increase in pluripotency genes expression and significant decrease in germ cell-specific genes expression. Also, we proved the differentiation capacity of embryonic stem-like cells to neuroepithelial-like cells which were immunoreactive to Nestin and Neurofilament 68. Evaluation of genes expression during in vitro differentiation into neuroepithelial-like cells showed high-level expression of Nestin whether this gene approximately has no expression in undifferentiated embryonic stem-like cells. Also, expression of pluripotency genes has significantly decreased in neuroepithelial-like cells compared with embryonic stem-like cells. This study shows that embryonic stem-like cells derived from testis are capable to differentiate into neuroepithelial-like cells that may provide a cellular reservoir usable for neurodegenerative disorders.  相似文献   
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