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Characteristic Genes (characteristic + gene)
Selected AbstractsMigration of mesenchymal cell fated to blastema is necessary for fish fin regenerationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 2 2008Yuki Nakatani Urodeles and fish have higher regeneration ability in a variety of tissues and organs than do other vertebrate species including mammals. Though many studies have aimed at identifying the cellular and molecular basis for regeneration, relatively little is known about the detailed cellular behaviors and involved molecular basis. In the present study, a small molecule inhibitor was used to analyzed the role of phosphoinositide 3-kinase (PI3K) signaling during regeneration. We showed that the inhibitor disrupted the formation of blastema including the expression of characteristic genes. The failure of blastema formation was due to the impaired migration of mesenchymal cells to the distal prospective blastema region, although it had a little affect on cell cycle activation in mesenchymal cells. Moreover, we found that the epidermal remodeling including cell proliferation, distal cell migration and Akt phosphorylation was also affected by the inhibitor, implying a possible involvement of epidermis for proper formation of blastema. From these data, we propose a model in which distinct signals that direct the cell cycle activation, mesenchymal cell migration and epidermal remodeling coordinate together to accomplish the correct blastema formation and regeneration. [source] Virulence genes of bovine Staphylococcus aureus from persistent and nonpersistent intramammary infections with different clinical characteristicsJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2007M. Haveri Abstract Aims:, To screen putative virulence genes in Staphylococcus aureus causing persistent and nonpersistent bovine intramammary infections (IMI) with different clinical characteristics. To examine, whether a possible relationship exists between genetic profile and infection persistence, clinical signs of infection, clonal type determined by pulsed-field gel electrophoresis (PFGE), and antimicrobial resistance. Methods and Results:, One-hundred and sixty-one S. aureus isolates derived from bovine IMI, consisting of 17 different PFGE types, were screened by conventional and multiplex-polymerase chain reaction (PCR) for 24 virulence genes for haemolysins (hla-hlg), leukocidins (lukED, lukM), exfoliative toxins (eta, etb), enterotoxins (sea-seo, seu), toxic-shock syndrome toxin (tst), and genes encoding penicillin (blaZ) and methicillin resistance (mecA). The majority of S. aureus isolated at the onset of mastitis carried haemolysin genes (76·7,97·4%), lukED (96·6%), and at least one gene for pyrogenic toxin superantigen (PTSAg) (69·0%). Strains carrying PTSAg-encoding genes were more common among predominant PFGE types and in persistent IMI. Strains concomitantly possessing sed, sej, and blaZ, putatively plasmid-encoded, were typically found in connection with persistent IMI. Conclusions:, Our results suggest that certain genetic elements are over-representative in S. aureus isolates especially from persistent bovine mastitis. This phenomenon seems to be in connection with clonal type and is often concomitant with penicillin resistance. Significance and Impact of the Study:, This is the first study to investigate associations between a large number of bacterial factors and outcome of S. aureus mastitis. The finding that widespread clonal types of S. aureus causing bovine mastitis of low treatment response may harbour characteristic genes could be improved for strain-specific diagnostic purposes. [source] Design and assessment of a tissue-engineered model of human phalanges and a small jointORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 4 2005WJ Landis Structured Abstract Authors ,, Landis WJ, Jacquet R, Hillyer J, Lowder E, Yanke A, Siperko L, Asamura S, Kusuhara H, Enjo M, Chubinskaya S, Potter K, Isogai N. Objectives ,, To develop models of human phalanges and small joints by suturing different cell-polymer constructs that are then implanted in athymic (nude) mice. Design ,, Models consisted of bovine periosteum, cartilage, and/or tendon cells seeded onto biodegradable polymer scaffolds of either polyglycolic acid (PGA) or copolymers of PGA and poly-L-lactic acid (PLLA) or poly- , -caprolactone (PCL) and PLLA. Constructs were fabricated to produce a distal phalanx, middle phalanx, or distal interphalangeal joint. Setting and Sample Population ,, Studies of more than 250 harvested implants were conducted at the Northeastern Ohio Universities College of Medicine. Experimental Variable ,, Polymer scaffold, cell type, and implantation time were examined. Outcome Measure ,, Tissue-engineered specimens were characterized by histology, transmission electron microscopy, in situ hybridization, laser capture microdissection and qualitative and quantitative polymerase chain reaction analysis, magnetic resonance microscopy, and X-ray microtomography. Results ,, Over periods to 60 weeks of implantation, constructs developed through vascularity from host mice; formed new cartilage, bone, and/or tendon; expressed characteristic genes of bovine origin, including type I, II and X collagen, osteopontin, aggrecan, biglycan, and bone sialoprotein; secreted corresponding proteins; responded to applied mechanical stimuli; and maintained shapes of human phalanges with small joints. Conclusion ,, Results give insight into construct processes of tissue regeneration and development and suggest more complete tissue-engineered cartilage, bone, and tendon models. These should have significant future scientific and clinical applications in medicine, including their use in plastic surgery, orthopaedics, craniofacial reconstruction, and teratology. [source] A novel tumor necrosis factor ,,responsive CCAAT/enhancer binding protein site regulates expression of the cartilage-derived retinoic acid,sensitive protein gene in cartilageARTHRITIS & RHEUMATISM, Issue 5 2008Toshihiro Imamura Objective Inflammatory processes in rheumatoid arthritis are primarily regulated by the cytokines tumor necrosis factor , (TNF,) and interleukin-1, (IL-1,). Previous studies in our laboratory have shown that IL-1, represses expression of the cartilage characteristic genes, cartilage-derived retinoic acid,sensitive protein (cd - rap) and type II collagen (COL2A1); this mechanism of repression involves activation of a CCAAT/enhancer binding protein (c/EBP) site within promoter regions. The aim of this study was to investigate novel TNF,-mediated mechanisms that regulate the expression of cd - rap. Methods Rat chondrosarcoma cells were transiently transfected with complementary DNA constructs encoding cd - rap, in the presence of TNF,. The expression of c/EBP,, SOX9, and p300 in rat chondrosarcoma cells and primary human articular chondrocytes after treatment with TNF, was examined by reverse transcription,polymerase chain reaction and Western blotting. The effect of TNF, on endogenous binding of c/EBP, or SOX9 to the cd - rap promoter was examined by chromatin immunoprecipitation assays. Results We identified a new c/EBP binding site in the cd - rap promoter (from position ,1059 bp to position ,1046 bp). Binding of c/EBP to this site was regulated by TNF, but not IL-1,, resulting in down-regulation of cd - rap expression. This effect was reversed by mutational inactivation of the c/EBP motif. In addition, the activation potential of SOX9 and CREB binding protein/p300 on the cd - rap promoter was enhanced after mutation of the new c/EBP binding site, indicating that blockage of this site would increase transcription. Conclusion TNF, regulates the expression and/or DNA-binding potential of key positive-acting and negative-acting transcription factors that control the expression of the cartilage matrix gene, cd - rap. [source] Gene expression profiling of cranial sensory ganglia that transmit food intake stimuliBIOFACTORS, Issue 1-4 2004Ichiro Matsumoto Abstract Peripheral cranial sensory nerves projecting into the oral cavity receive food intake stimuli and transmit sensory signals to the central nervous system. They are derived from four cranial sensory ganglia, trigeminal, geniculate, petrosal, and nodose ganglia, each of which contains multiple kinds of sensory neurons with different cell morphologies and neuronal properties. We investigated the complex properties of these neurons from the viewpoint of gene expression using DNA microarrays. The 498 genes were selected from a total of 8,740 genes as showing tissue-dependent expression on the microarray by hierarchical cluster analysis, in which several genes known to be differentially expressed in cranial sensory ganglia are included. This suggests that DNA microarray cluster analysis revealed a number of characteristic genes for sensory neurons in these ganglia. Among the selected 498 genes, 44 genes are associated with neurotransmission, such as neuropeptides, their receptors, and vesicle transport, and 26 are ion channels regulating membrane potentials. The identification of a number of genes related directly to neural properties indicates that these sensory ganglia contain heterogeneous types of neurons with different neural properties. [source] | |||||||||||||