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781.
Spermatogonial stem cells are unique cells of testes that can restore fertility upon transplantation into recipient testes. However, use of suitable markers for enrichment of these cells have important potential application. THY1, is an established conserved marker of spermatogonial stem cells in bovine, rodents, and primates, but there is no information available in goats. After three rounds of enzymatic digestion of prepubertal goat testicular tissues, undifferentiated spermatogonia positive for THY1 were isolated by magnetic-activated cell sorting and were used for immunocytochemistry, real-time polymerase chain reaction analysis for gene expression, protein expression, and transplantation into recipient mice. Immunocytochemical analyses showed that significantly higher percentage of THY1+ cells were positive for PLZF and VASA when compared with unselected population. This result for PLZF was further confirmed at the protein level. Real-time polymerase chain reaction analysis revealed that expression of THY1, PLZF, VASA, BCL6B, and UCHL1 as SCCs characteristic genes in THY1+ cells was significantly higher than in the initial population. Finally, transplantation of PKH26-labeled cells revealed that THY1+ cells had higher capacity for colony formation when compared with unselected cells. In conclusion, the results provide indications that THY1 surface marker can be reliably used for enrichment of undifferentiated spermatogonial in the goats.  相似文献   
782.
Brown rust disease is one the most important fungal disease of wheat in Iran. Using of resistance cultivars is the best control method of disease. In this study, genetic resistance of 82 promising lines was evaluated in green house condition. Their resistance components included Infection Type, Latent Period, Postule Size and Postule Density in the randomised complete block design with two replications. In the molecular level for lines with corresponding adult plant resistance Lr34 gene, PCR process by means of STS marker and the primer Lr34/Yr18 was done. The results of variance analysis obtained implicated a significant difference in the 1% probable. The minimum value detected as ?0.88 to the Gorgan isolate and the maximum value for ?0.94 to Ahwaz isolate. In the cluster analysis related to two isolates, lines were divided to four groups composed. The presence of gene Lr34 was proved into the two genotypes “ER-S8–90” and “ER-N3–90”.  相似文献   
783.
The genus Pythium, with slightly over 140 described species, has been classified traditionally with other filamentous, coenocytic, sporangia-producing fungi as “Phycomycetes”. However, with recent advances in chemical, ultrastructural and molecular studies, Pythium spp. are now considered as “fungus-like organisms” or “pseudo-fungi” and are placed in the kingdom Chromista or kingdom Stramenopila, distinct from the true fungi or the kingdom Fungi. There is no comprehensive web-based identification key available for the identification of all described Pythium species. This article describes a web-based identification tool (which has been described by the authors under the name of Fungid) that uses morphological features. For the isolate in question, the software compares the unknown isolate with near to 90 known species submitted in the database. One or more than one species is suggested to the user by the software.  相似文献   
784.
Simplified multiple-locus variable-number tandem repeat analysis (MLVA) was developed using one-shot multiplex PCR for seven variable-number tandem repeats (VNTR) markers with high diversity capacity. MLVA, phage typing, and PFGE methods were applied on 34 diverse Salmonella Enteritidis isolates from human and non-human sources. MLVA detected allelic variations that helped to classify the S. Enteritidis isolates into more evenly distributed subtypes than other methods. MLVA-based S. Enteritidis clonal groups were largely associated with sources of the isolates. Nei's diversity indices for polymorphism ranged from 0.25 to 0.70 for seven VNTR loci markers. Based on Simpson's and Shannon's diversity indices, MLVA had a higher discriminatory power than pulsed field gel electrophoresis (PFGE), phage typing, or multilocus enzyme electrophoresis. Therefore, MLVA may be used along with PFGE to enhance the effectiveness of the molecular epidemiologic investigation of S. Enteritidis infections.  相似文献   
785.
To date, a few numbers of bacteriophages that infect Lactococcus garvieae have been identified, but their complete genome sequences have not yet been investigated. For the first time, herein, the complete DNA sequence of a new phage of L. garvieae (phage WP-2) is reported and analyzed. The morphological characteristics indicated that the phage had a small isometric head along with a short and non-contractile tail, suggesting that WP-2 belongs to the family Podoviridae. Bioinformatic analysis revealed that phage WP-2 can be classified as a new member of Ahjdlikevirus in the Picovirinae subfamily because it had a small dsDNA of 18,899 bp with 24 open reading frames and a protein-primed DNA polymerase. The phage nucleotide sequence and predicted protein products have been identified to share very limited evidence of homology with complete genome and proteome of other phages. To our knowledge, this is the first Ahjdlikevirus bacteriophage which can infect a member of the Lactococcus genus.  相似文献   
786.
787.
788.
This study was conducted on 87 patients with chronic periodontitis (CP), 50 patients with peri-implantitis and 90 periodontally healthy individuals referring to the Department of Periodontics for evaluating the association between Fc gamma-receptor genes polymorphisms with CP and peri-implantitis. After obtaining consent, venous blood samples (5cc) were obtained from patients and DNA was extracted using Miller's salting-out method. Polymerase chain reaction (PCR)-restriction fragment length polymorphism and tetra-primer amplification refractory mutation system-PCR methods were used to assess the polymorphisms of FcγRs IIa, IIIa, and IIIb genes. Analyzing showed a significant association between specific genotypes with increasing CP and peri-implantitis risks in codominant and dominant models. For FcγR IIIa, analyzing revealed a significant association between specific genotypes with increasing CP and peri-implantitis risks in codominant, dominant, and recessive models. For FcγR IIIb, we also detected a significant association between specific genotypes with increasing CP and peri-implantitis risks in codominant, dominant, and recessive models ( P < 0.05). According to the results of this study, the FCGRIIa (rs1801274), FCGRIIIa (rs396991), and FCGRIIIb (rs1050501) polymorphisms were significantly associated with CP and peri-implantitis and may have a role in the pathogenesis of these diseases.  相似文献   
789.
The function of fibroblast cells in wounded areas results in reconstruction of the extra cellular matrix and consequently resolution of granulation tissue. It is suggested that the use of platelet-rich plasma can accelerate the healing process in nonhealing or slow-healing wounds. In this study, a simple and novel method has been used to fabricate an electrospun three-layered scaffold containing plasma rich in growth factor with the aim of increasing the proliferation and migration of fibroblast cells in vitro. First, plasma rich in growth factor was derived from platelet rich plasma, and then a three-layered scaffold was fabricated using PLLA nanofibers as the outer layers and plasma rich in growth factor-containing gelatin fibers as the internal layer. The growth morphology of cells seeded on this scaffold was compared to those seeded on one layered PLLA scaffold. The study of the cell growth rate on different substrates and the migration of cells in response to the drug release of multilayered scaffold was investigated by the cell quantification assay and a modified under agarose assay. Scanning electron microscopy and fluorescence images showed that cells seeded on multilayered scaffold were completely oriented 72 hours after seeding compared to those seeded on PLLA scaffold. The cell quantification assay also indicated significant increase in proliferation rate of cells seeded on three-layered scaffold compared to those seeded on PLLA scaffold and finally, monitoring cell migration proved that cells migrate significantly toward the three-layered scaffold up to 48 to 72 hours and afterwards start to show a diminished migration rate toward this scaffold.  相似文献   
790.
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