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71.
Highlights? Nanog is a direct target of Activin and SMAD2/3 but not FGF-ERK in EpiSCs ? FGF signaling inhibits neuroectodermal commitment of EpiSCs and hESCs ? FGF inhibition relieves Klf2 repression and reverts EpiSCs to an ESC-like state ? mESCs transition to an EpiSC-like state with LIF inhibition and FGF activation  相似文献   
72.
Studies on the genetic variation in marginal populations and differentiation between them are essential for assessment of best gene conservation strategies and sampling schemes. In this study, ISSR markers were used to establish the level of genetic relationships and polymorphism 50 genotypes of Salvadora persica collected from 6 different regions of Hormozgan province. The ISSR analysis with 9 anchored primers also generated 105 scorable loci, of which 85 were polymorphic (80.95%). Parameters of genetic diversity and its partitioning were calculated. The genetic analysis demonstrated that S. persica maintain relatively high genetic diversity (PIC was 0.63, Na was 1.27 and Ho and He were 0.15 and 0.17 respectively). The coefficient of genetic differentiation among populations based on FST equaled 0.20. Genetic identities between population's pairs were high (mean I?=?0.88). These values are high as compared with other widespread congener species. Cluster analysis based on the Unweighted Pair Group Method with Arithmetic Averages (UPGMA) revealed 3 main clusters for the ISSR data. The levels of genetic diversity maintained within populations of S. persica indicate that an appropriate sampling design for ex situ safeguarding should capture the majority of genetic diversity found within these taxa to help ensure the long term viability of this species. Furthermore, it could be inferred that ISSR markers are suitable tools for the evaluation of genetic diversity and relationships within the Salvadora persica.  相似文献   
73.
74.
Bone morphogenetic protein (BMP)-4 has a crucial role on primordial germ cells (PGCs) development in vivo which can promote stem cell differentiation to PG-like cells. In this study, we investigated the expression of Mvh as one of the specific genes in primordial germ cells after treatment with different doses of BMP4 on bone mesenchymal stem cells (BMSCs)-derived PGCs. Following isolation of BMSCs from male mouse femur and tibia, cells were cultured in medium for 72 h. Passage 4 murine BMSCs were characterized by CD90, CD105, CD34, and CD45 markers and osteo-adipogenic differentiation. Different doses of BMP4 (0, 0.01, 0.1, 1, 5, 25, 50, and 100 ng/ml) were added to BMSCs for PGCs differentiation during 4-days culture. Viability percent, proliferation rates, and expression of Mvh gene were analyzed by RT-qPCR. Data analysis was done with ANOVA test. CD90+, CD105+, CD34, and CD45 BMSCs were able to differentiate to osteo-adipogenic lineages. The results revealed that proliferation rate and viability percent were raised significantly (p ≤ 0.05) by adding 1, 5, 25 ng/ml of BMP4 and there were decreased to the lowest rate after adding 100 ng/ml BMP4 (p ≤ 0.05). There were significant up regulation (p ≤ 0.05) in Mvh expression between 25, 50, and 100 ng/ml BMP4 with other doses. So the selective dose of BMP-4 for treatment during 4-day culture was 25 ng/ml. The results suggest that addition of 25 ng/ml BMP4 had the best effects based on gene-specific marker expression.  相似文献   
75.
Cytochrome P450 CYP141 is an intermediary metabolic and respiratory protein that interferes with oxidation reduction in Mycobacterium tuberculosis. This conserved protein has also been debated as a hypothetical target for therapeutics. We used the sequences of CYP141 gene to develop a PCR for rapid detection of Mycobacterium tuberculosis from respiratory specimens. The sensitivity of this PCR for culture positive-smear positive and culture positive-smear negative samples were 92% and 62.5%, respectively. The overall sensitivity and specificity of this PCR was 85.7% and 97.8%. As compared with other studies, it appears that the CYP141 gene is a good target for direct detection of M. tuberculosis from respiratory specimens.  相似文献   
76.
ABSTRACT: BACKGROUND: Clinical governance (CG) is among the different frameworks proposed to improve the quality of healthcare. Iran, like many other countries, has put healthcare quality improvement in its top health policy priorities. In November 2009, implementation of CG became a task for all hospitals across the country. However, it has been a challenge to clarify the notion of CG and the way to implement it in Iran. The purpose of this action research study is to understand how CG can be defined and implemented in a selected teaching emergency department (ED).Methods/designWe will use Soft Systems Methodology for both designing the study and inquiring into its content. As we considered a complex problem situation regarding the quality of care in the selected ED, we initially conceptualized CG as a cyclic set of purposeful activities designed to explore the situation and find relevant changes to improve the quality of care. Then, implementation of CG will conceptually be to carry out that set of purposeful activities. The activities will be about: understanding the situation and finding out relevant issues concerning the quality of care; exploring different stakeholders' views and ideas about the situation and how it can be improved; and defining actions to improve the quality of care through structured debates and development of accommodations among stakeholders. We will flexibly use qualitative methods of data collection and analysis in the course of the study. To ensure the study rigor, we will use different strategies. DISCUSSION: Successful implementation of CG, like other quality improvement frameworks, requires special consideration of underlying complexities. We believe that addressing the complex situation and reflections on involvement in this action research will make it possible to understand the concept of CG and its implementation in the selected setting. By describing the context and executed flexible methods of implementation, the results of this study would contribute to the development of implementation science and be employed by boards and executives governing other clinical settings to facilitate CG implementation.  相似文献   
77.
The wound infection is one of the frequent complications in patients undergoing surgical operations. Staphylococcus aureus is the most common cause of surgical wounds. Artemisia absinthium has been shown to bear strong antimicrobial activity, especially against Gram-positive pathogens. This study was designed to investigate the antimicrobial effects of A. absinthium against surgical wounds infected by S. aureus in a rat model. Twenty male Sprague–Dawley rats were divided randomly into two equal groups of treated and control rats. A circular incision was created on the dorsal inter-scapular region of each rat. After skin wounding, rats were inoculated locally with 1 × 104 CFU of S. aureus at sites of skin wounds. The extract was applied topically twice a day throughout the experiment. Animals of the control group were left untreated. Results have revealed that topical application of A. absinthium extract on the infected wound sites produced significant antibacterial activity against S. aureus.  相似文献   
78.
A 3-year study was conducted to evaluate the effectiveness of two disease-suppressive Streptomyces spp. to control sugar beet Rhizoctonia solani damping off under field conditions. Streptomyces seed treatments reduced seedling damping off in naturally (2005) and artificially (2006 and 2007) infested soils. All biocontrol agents provided better efficacy than Vitavax to control seedling damping-off. There were no significant differences among Streptomyces isolates. Isolate C increased plant stand by 19.5, 50.5 and 53.75% in 2005, 2006 and 2007, respectively. Evaluation of final harvest revealed that the root yield of the biocontrol agents increased compared to untreated control in these years.  相似文献   
79.

Objective

Musculodegenerative diseases threaten the life of many patients in the world. Since drug administration is not efficient in regeneration of damaged tissues, stem cell therapy is considered as a good strategy to restore the lost cells. Since the efficiency of myogenic differentiation potential of human Chorion- derived Mesenchymal Stem Cells (C-MSCs) has not been addressed so far; we set out to evaluate myogenic differentiation property of these cells in comparison with Umbilical Cord Blood- derived Mesenchymal Stem Cells (UCB-MSCs) in the presence of 5-azacytidine.

Materials & methods

To do that, neonate placenta Umbilical Cord Blood were transferred to the lab. After characterization of the isolated cells using flowcytometry and multilineage differentiation capacity, the obtained Mesenchymal Stem Cells were cultured in DMEM/F12 supplemented with 2% FBS and 10 μM of 5-azacytidine to induce myogenic differentiation. Real-time PCR and immunocytochemistry were used to assess the myogenic properties of the cells.

Results

Our data showed that C-MSCs and UCB-MSCs were spindle shape in morphology. They were positive for CD90, CD73 and CD44 antigens, and negative for hematopoietic markers. They also differentiated into osteoblast and adipoblast lineages. Real-time PCR results showed that the cells could express MyoD, desmin and α-MHC at the end of the first week (P < 0.05). No significant upregulation was detected in the expression of GATA-4 in both groups. Immunocytochemical staining revealed the expression of Desmin, cTnT and α-MHC.

Conclusions

Results showed that these cells are potent to differentiate into myoblast- like cells. An upregulation in the expression of some myogenic markers (desmin, α- MHC) was observed in C-MSCs in comparison with UCB-MSCs.  相似文献   
80.
Vaginal prolapse is the protrusion of edematous vaginal tissue into and through the opening of the vulva occurring during the pro-oestrus and oestrus stages of the sexual cycle. True vaginal prolapse may occur near parturition, as the concentration of serum progesterone declines and the concentration of serum oestrogen increases. In a bitch, true vaginal prolapse is a very rare condition. This case report describes an 18-month-old crossbreed bitch, weighing 40 kg presented with type III vaginal prolapse. The patient had developed vaginal prolapse after receiving oestrogen in order to oestrus induction. Subsequent to unsuccessful attempts for repositioning, ovariohysterectomy (OHE), circumferential excision of the prolapsed tissue and finally vulvoplasty were performed. There was no evidence of recurrence of the prolapse during 30 days after surgery. This case report describes type III vaginal prolapse as an unusual side effect of oestrus induction hormonal therapy in the bitch.  相似文献   
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