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81.
The isolation and characterization of stem cells from an alternative tissue is a subject of intensive investigation. In the present study, we have focused on the characterization of fibroblastic cells in olfactory bulb tissue of the rat. To this end, 4-6 week old rats were killed and their olfactory bulb tissue was dissected out. Olfactory bulb derived fibroblast-like cells were recovered by adhesion to cell culture plastic. The plastic adherent cultivated cells were induced to differentiate along osteoblastic, adipogenic and chondrogenic lineages. Furthermore, the expression of some surface antigens was investigated. We obtained purified cells with spindle shaped morphology in primary culture, which differentiated into mesenchymal lineages. These cells expressed CD29 and CD90 (Thy1.1) surface antigens, but not CD31, CD34 and CD45. Our results indicate that fibroblast-like cells from the olfactory bulb are mesenchymal stem cells in nature. Taken together, our data suggest that olfactory bulb tissue may constitute a new source of mesenchymal stem cells and could be used for the treatment of injury.  相似文献   
82.
Background: On May 5, 2014, the Iranian Ministry of Health and Medical Education launched the Health Transformation Plan (HTP) as a major healthcare reform to curb out-of-pocket (OOP) expenses and protect people from catastrophic health expenditures (CHEs). Therefore, in this study, we conducted a comprehensive literature search with the aim of systematically investigating the impacts of HTP on OOP and CHE after the implementation of the plan. Method: Web of Science, PubMed, Scopus, Embase, and Iranian bibliographic thesauri and repositories such as MagIran, Elmnet, and Scientific Information Database were searched. Studies published between May 2014 and December 2020 that reported the impact of HTP on the financial indicators under investigation in this study (OOP and CHEs) that were conducted in Iran. Estimated pooled change both for OOP and CHEs was calculated as effect size utilizing meta-analytical techniques. Also, heterogeneity among studies was assessed with the I2 statistics. Results: Seventeen studies were included, nine of which evaluated the OOP index, six studies assessed the CHEs index, and two studies examined both the OOP and CHEs indexes. The OOP was found to decrease after the implementation of the HTP (with an estimated decrease of 13.02% (95% CI: 9.09-16.94). Also, CHEs experienced a decrease of 5.80% (95% CI: 3.85-7.74). Conclusion: The findings show that the implementation of HTP has reduced health costs. In this regard and in order to keep reducing the costs that many people are unable to pay, the government and other organizations involved in the health system should provide sustainable financial resources in order to continue running HTP. However, there remain gaps and weaknesses that can be solved through discussion with all the actors involved.  相似文献   
83.
Plant architecture is defined by fates and positions of meristematic tissues and has direct consequences on yield potential and environmental adaptation of the plant. In strawberries (Fragaria vesca L. and F. × ananassa Duch.), shoot apical meristems can remain vegetative or differentiate into a terminal inflorescence meristem. Strawberry axillary buds (AXBs) are located in leaf axils and can either remain dormant or follow one of the two possible developmental fates. AXBs can either develop into stolons needed for clonal reproduction or into branch crowns (BCs) that can bear their own terminal inflorescences under favorable conditions. Although AXB fate has direct consequences on yield potential and vegetative propagation of strawberries, the regulation of AXB fate has so far remained obscure. We subjected a number of woodland strawberry (F. vesca L.) natural accessions and transgenic genotypes to different environmental conditions and growth regulator treatments to demonstrate that strawberry AXB fate is regulated either by environmental or endogenous factors, depending on the AXB position on the plant. We confirm that the F. vesca GIBBERELLIN20-oxidase4 (FvGA20ox4) gene is indispensable for stolon development and under tight environmental regulation. Moreover, our data show that apical dominance inhibits the outgrowth of the youngest AXB as BCs, although the effect of apical dominance can be overrun by the activity of FvGA20ox4. Finally, we demonstrate that the FvGA20ox4 is photoperiodically regulated via FvSOC1 (F. vesca SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1) at 18°C, but at higher temperature of 22°C an unidentified FvSOC1-independent pathway promotes stolon development.

Environmental conditions and apical dominance dictate woodland strawberry plant architecture by regulating axillary bud fate.  相似文献   
84.
Conductive nanofibrous scaffolds with that can conduct electrical current have a great potential in neural tissue engineering. The purpose of this study was to survey effects of electrical stimulation and polycaprolactone/polypyrrole/multiwall carbon nanotube (PCL/PPY/MWCNTs) fibrous scaffold on photoreceptor differentiation of trabecular meshwork mesenchymal stem cells (TM-MSCs). PCL/PPY/MWCNTs scaffold was made by electrospinning method. TM-MSCs were seeded on PCL/PPY/MWCNTs scaffold and stimulated with a potential of 115 V/m. Scanning electron microscopy, transmission electron microscopy, and FT-IR were used to evaluate the fabricated scaffold. Immunofluorescence and quantitative real-time polymerase chain reaction were used to examine differentiated cells. Scanning electron microscopy, transmitting electron microscopy, and FT-IR confirmed the creation of the composite structure of fibers. RT-qPCR analysis showed that the expression of rhodopsin and peripherin genes in electrically stimulated cells were significantly higher (5.7- and 6.23-fold, respectively; p ≤ 0.05) than those with no electrical stimulation. Collectively, it seems that the combination of PCL/PPY/MWCNTs scaffold, as a suitable conductive scaffold, and electrical stimulation could be an effective approach in the differentiation of stem cells in retinal tissue engineering.  相似文献   
85.
86.
Umbelliprenin (UMB) has shown various pharmacological properties in vitro. We investigated the antineoplastic and immunostimulatory effects of UMB in 4T1 mammary‐tumor‐bearing mice. Two‐hundred microliter of UMB (12.5 mg/ml) was intraperitoneally administrated to healthy and tumor‐bearing female Balb/c mice for a period of 18 days. Data was analyzed using GraphPad Prism 5 software for Windows (version 5, La Jolla, CA). UMB caused a significant decrease in tumor size (P < 0.01). Serum interferon gamma (IFNγ) was augmented in both healthy and tumor‐bearing animals (P < 0.01), and IL‐4 declined in healthy animals (P < 0.01) treated with UMB. Expressions of Ki‐67, VEGF, CD31, MMP2, MMP9, VCAM1, and NF‐κB were significantly decreased in tumors from UMB‐treated animals (P < 0.001), whereas E‐Cadherin and TNFR1 expressions were markedly increased (P < 0.001). The rates of liver and lung metastases in UMB‐administrated animals were smaller compared to the control. UMB can potently inhibit tumor growth, angiogenesis, metastasis, and inflammation and potentiate an antitumor immune response in vivo. However, further investigations are required to evaluate the UMB mechanisms of action in cancerous cells.  相似文献   
87.
Bloodstream forms of African trypanosomes are dependent on their host for fatty acids, choline and other components of membrane lipids. The bulk of their choline requirement is met by their ability to take up lysophospholipids from the host tissue fluids. Trypanosoma brucei has ocyltransferose and phospholipase A(1) activities for the metabolism of exogenous lysophospholipids. The rate of uptake of lysophospholipids can be controlled by changes in the extrocellulor concentration of fatty ocyl-coenzyme A, and this control has potential for chemotherapy.  相似文献   
88.
89.
Despite the advantages of transplantation of umbilical cord blood's (UCB's) hematopoietic stem cells (uHSCs) for hematologic malignancy treatment, there are two major challenges in using them: (a) Insufficient amount of uHSCs in a UCB unit; (b) a defect in uHSCs homing to bone marrow (BM) due to loose binding of their surface glycan ligands to BM's endothelium selectin receptors. To overcome these limitations, after poly l -lactic acid (PLLA) scaffold establishment and incubation of uHSCs with fucosyltransferase-VI and GDP-fucose, ex vivo expansion of these cells on selectin-coated scaffold was done. The characteristics of the cultured fucosylated and nonfucosylated cells on a two-dimensional culture system, PLLA, and a selectin-coated scaffold were evaluated by flow cytometry, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, colony-forming unit (CFU) assay, and CXCR4 expression at the messenger RNA and protein levels. According to the findings of this study, optimized attachment to the scaffold in scanning electron microscopy micrograph, maximum count of CFU, and the highest 570 nm absorption were observed in fucosylated cells expanded on selectin-coated scaffolds. Furthermore, real-time polymerase chain reaction showed the highest expression of the CXCR4 gene, and immunocytochemistry data confirmed that the CXCR4 protein was functional in this group compared with the other groups. Considered together, the results showed that selectin-coated scaffold could be a supportive structure for fucosylated uHSC expansion and homing by nanotopography. Fucosylated cells placed on the selectin-coated scaffold serve as a basal surface for cell–cell interaction and more homing potential of uHSCs. Accordingly, this procedure can also be considered as a promising technique for the hematological disorder treatment and tissue engineering applications.  相似文献   
90.
Maternal parasitoses modulate fetal immune development, manifesting as altered cellular immunological activity in cord blood that may be linked to enhanced susceptibility to infections in early life. Plasmodium falciparum typifies such infections, with distinct placental infection-related changes in cord blood exemplified by expanded populations of parasite antigen-specific regulatory T cells. Here we addressed whether such early-onset cellular immunological alterations persist through infancy. Specifically, in order to assess the potential impacts of P. falciparum infections either during pregnancy or during infancy, we quantified lymphocyte subsets in cord blood and in infants'' peripheral blood during the first year of life. The principal age-related changes observed, independent of infection status, concerned decreases in the frequencies of CD4+, NKdim and NKT cells, whilst CD8+, Treg and Teff cells'' frequencies increased from birth to 12 months of age. P. falciparum infections present at delivery, but not those earlier in gestation, were associated with increased frequencies of Treg and CD8+ T cells but fewer CD4+ and NKT cells during infancy, thus accentuating the observed age-related patterns. Overall, P. falciparum infections arising during infancy were associated with a reversal of the trends associated with maternal infection i.e. with more CD4+ cells, with fewer Treg and CD8+ cells. We conclude that maternal P. falciparum infection at delivery has significant and, in some cases, year-long effects on the composition of infants'' peripheral blood lymphocyte populations. Those effects are superimposed on separate and independent age- as well as infant infection-related alterations that, respectively, either match or run counter to them.  相似文献   
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