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Concomitant Expression (concomitant + expression)
Selected AbstractsProstaglandin D2 pathway and peroxisome proliferator-activated receptor ,-1 expression are induced by mechanical loading in an osteoblastic cell lineJOURNAL OF PERIODONTAL RESEARCH, Issue 2 2006Chitpol Siddhivarn Objective:, The hypothesis underlying the current study was that the arachidonic acid cascade, specifically activation of the prostaglandin (PG) D2 pathway in osteoblasts, is an anabolic signal induced by mechanical loading. Background:, Previous studies have shown that mechanical loading of osteoblasts triggers cyclooxygenase (COX)-2, PGE2 and prostacyclin (PGI2) synthesis. Since modest mechanical loading of osteoblasts promotes bone formation, we sought to determine whether mechanical stress activates the osteoblastic PGD2 pathway resulting in the synthesis of osteogenic cyclopentenones, including ,12PGJ2. Methods:, Osteoblast monolayers were stretched using a Bioflex apparatus at a frequency of 1 Hz with 1% elongation. Cells and cell media were collected at various time points: 5, 10, 15, 30 min; and 1, 4, 16, 24 h. RNA was extracted for quantitative reverse transcriptase,polymerase chain reaction (RT,PCR). In certain experiments, cells were pre-labeled with 14C arachidonic acid prior to stretching. Radiolabeled metabolites in cell media were identified by reverse-phase high performance liquid chromatography (RP-HPLC). Osteoblasts were evaluated for an induction in bone nodule formation by stretching. Results:, Mechanical strain significantly increased mRNA expression of COX-1, COX-2, PGD2 synthase and peroxisome proliferator-activated receptor (PPAR) ,-1, but not of PPAR,-2 as compared to control unstretched cells (p < 0.05). Mechanical loading stimulated the release of PGE2, PGD2 and the PGD2 metabolite ,12PGJ2. Mechanical strain resulted in the induction of bone nodules. Conclusions:, This report indicates that mechanical loading of osteoblasts results in activation of PGD2 and the concomitant expression of transcription factor PPAR,-1 mRNA. The coordinated synthesis of ,12PGJ2, a natural ligand for PPAR,-1, with the increased expression of PPAR,-1, suggests that biomechanical transduction pathways that initially involve the activation of cyclooxygenases may also involve the activation of the ,12PGJ2,PPAR pathway. [source] Enhancement of matrix metalloproteinase (MMP)-2 activity in gingival tissue and cultured fibroblasts from Down's syndrome patientsORAL DISEASES, Issue 1 2001T Komatsu OBJECTIVES: To identify one of the possible factors responsible for periodontal disease in Down's syndrome (trisomy 21) patients, we studied the enzyme activity and the mRNA expression pattern of matrix metalloproteinases (MMPs) of cultured gingival fibroblasts (GF) and fresh gingival tissues. MATERIALS AND METHODS: Gingival tissue was used as the cell source and was biopsied at the time of dental treatment from nine patients with Down's syndrome and nine non-Down's controls. GF were cultivated in serum-free media for analyses of their MMP activities at the transcription or the protein level. The MMP activities in the supernates were measured by gelatin impregnated zymography. Relative levels of MMP mRNA from the cultured GF or freshly isolated gingival tissues were determined using the reverse transcription polymerase chain reaction (RT-PCR). RESULT AND CONCLUSIONS: The production of the active type of MMP-2 in GF from Down's syndrome patients (D-GF) was found to be significantly higher (P < 0.05) than that of the control GF (C-GF) at the protein level. The mRNA expressions of membrane-type1 MMP (MT1-MMP) and MMP-2 in D-GF were constitutively augmented when compared with those of C-GF. These findings suggest that specific increase of the active form of MMP-2 in D-GF may possibly be due to the concomitant expression of MT1-MMP in the cultured cells, and this could be related to the pathogenesis of gingivitis/periodontitis associated with Down's syndrome patients. [source] Coexpression of heparanase, basic fibroblast growth factor and vascular endothelial growth factor in human esophageal carcinomasPATHOLOGY INTERNATIONAL, Issue 8 2004Shuji Mikami Heparan sulfate (HS), which is degraded by heparanase, plays an important role in cell adhesion, insolubility of the extracellular matrix (ECM) and as a reservoir for various growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). In the present study, we examined the immunohistochemical expression of heparanase, bFGF and VEGF, and evaluated the correlation between their expression and microvessel density (MVD) in human esophageal carcinomas. Heparanase, bFGF and VEGF were immunolocalized predominantly to the carcinoma cells, but they were also localized to the endothelial cells of microvessels near the carcinoma cell nests. In carcinomas with invasion of the muscular layer or adventitia, heparanase staining was stronger at the invasive areas of carcinomas than the intraepithelial spread. Expression of heparanase and bFGF and the degree of MVD were associated, with, tumor, invasion,, lymph, node, metastasis, and pathological stages. Cases with positive staining for heparanase, bFGF or VEGF tended to have a higher MVD than those without staining, and carcinomas with concomitant expression of heparanase, bFGF and VEGF showed the highest MVD. The level of heparanase mRNA expression was directly correlated with the MVD. In addition, heparanase-positive cases had a higher positive ratio of bFGF and VEGF compared with the heparanase-negative cases. These data suggest the possibility that heparanase may contribute to not only cancer cell invasion but also angiogenesis probably through degradation of HS in the ECM and release of bFGF and VEGF from the HS-containing ECM. [source] Increased nitric oxide production in nasal epithelial cells from allergic patients , RT-PCR analysis and direct imaging by a fluorescence indicator: DAF-2 DA*CLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2001S. Takeno Background Nitric oxide (NO) is believed to participate in the regulation of airway clearance and non-specific cellular immunity. Recent studies have suggested that airway epithelial cells of allergic and non-allergic individuals may differ in their ability to produce this molecule. Objective The aim of this study was to detect the difference in NO production in human nasal epithelial cells between normal subjects and patients with perennial allergic rhinitis (AR), and to assess the relationship between the expression of nitric oxide synthase (NOS) isoforms and the severity of the disease. Methods Nasal epithelial cells were obtained from the inferior turbinate. The expression of mRNAs encoding constitutive endothelial NOS (eNOS) and inducible NOS (iNOS) was studied by reverse transcription-polymerase chain reaction (RT-PCR). Direct NO production in living cells was visualized and quantified by a fluorescent indicator, DAF-2 DA. Results RT-PCR analysis demonstrated that AR patients with a RAST score of 5 or 6 showed significant increases in the levels of iNOS mRNA and slight reductions in those of eNOS mRNA. Patients with a RAST score of 2,4 also revealed the same tendency however, the difference was not significant. DAF-2 DA imaging demonstrated that epithelial cells, especially the ciliated cells, produced a larger amount of NO than non-epithelial inflammatory cells. Preincubation with L-NAME resulted in an approximate 40% decrease in both groups. Conclusion These results directly indicate that nasal epithelial cells of AR patients overall produce higher levels of NO through the concomitant expression of different NOS isoforms. Continuous NO production by the epithelial cells in normal subjects further support the hypothesis that NO derived from epithelium may play dual roles in the regulation of nasal airway clearance and in the host defense. In addition, the use of DAF-2 DA provides a reliable method to visualize and quantify the direct NO production of living cells. [source] High prevalence of carbapenem-hydrolysing oxacillinases in epidemiologically related and unrelated Acinetobacter baumannii clinical isolates in SpainCLINICAL MICROBIOLOGY AND INFECTION, Issue 12 2007M. Ruiz Abstract Carbapenem-hydrolysing oxacillinases are reported increasingly in Acinetobacter baumannii. This study investigated the role of these ,-lactamases in causing resistance to carbapenems in 83 epidemiologically related and unrelated imipenem-resistant A. baumannii clinical isolates. The isolates were also analysed for the presence of ISAba1 in the promoter region of the blaOXA-51 -like gene in order to investigate the role of ISAba1 in OXA-51 expression. All clinical isolates contained a blaOXA-51 -like gene, 20% contained a blaOXA-58 -like gene, and 42% contained a blaOXA-40 -like gene; blaOXA-23 -like, blaIMP and blaVIM genes were not detected in any of the isolates investigated. ISAba1 was found in 24 (82.7%) of 28 pulsetypes, and was located in the promoter region of the blaOXA-51 -like gene in five (20.8%) of these pulsetypes. Expression of blaOXA-51 was detected in the five isolates with ISAba1 located in the promoter region, but was not detected in an isogenic imipenem-susceptible A. baumannii isolate that did not have ISAba1 located in the promoter region. It was concluded that there is a high prevalence of oxacillinases with activity against carbapenems among genetically unrelated A. baumannii clinical isolates from Spain, and that concomitant expression of two carbapenemases (OXA-51-like and either OXA-40-like or OXA-58-like) may take place. Insertion of an ISAba1 -like element in the promoter of the blaOXA-51 -like gene promotes the expression of this gene, although this did not seem to play a major role in carbapenem resistance. [source] Cellular neurothekeoma with histiocytic differentiationJOURNAL OF CUTANEOUS PATHOLOGY, Issue 8 2004Noriyuki Misago Background:, It is generally accepted that the two types of neurothekeoma (myxoid type and cellular type) represent the two poles of a spectrum. This concept, however, has recently been challenged, and cellular neurothekeomas have been suggested as a separate classification and are included in the ,fibrohistiocytic' category by some authors. Cellular neurothekeomas have been reported to show negative immunohistochemical staining for histiocytic markers, and PG-M1 is now considered to be the most reliable histiocytic marker. Case report:, We report a case of cellular neurothekeoma. The histopathological features in this case were typical for cellular neurothekeoma. Immunohistochemically, the neoplastic cells were diffusely positive for S-100A6 protein, PGP9.5, CD10, CD68 (KP1), PG-M1, and Vimentin, and negative for other antibodies including S-100 protein and factor XIIIa. Conclusions:, Cellular neurothekeoma expressing both KP-1 and PG-M1 is considered to show histiocytic differentiation, and may be interpreted as a neoplasm with immature nerve sheath differentiation, incidentally expressing histiocytic markers, or as an undifferentiated neoplasm derived from the neural crest cells of nerve sheath/fibrohistiocyte lineage. These results, such as the concomitant expressions of PGP9.5/S-100A6 and PG-M1/CD68 (KP-1), support the theory of multiple differentiation in cellular neurothekeomas. The significance of the expression of CD10 in this cellular neurothekeoma is unclear. [source] | ||||||||||