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1.
Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment.  相似文献   
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BACKGROUND: Atherosclerotic vascular diseases are the major cause of mortality in patients with end-stage renal disease (ESRD) treated with chronic peritoneal dialysis (CPD), even in children. Adiponectin (ADPN) is a recently discovered adipocyte-derived plasma protein having anti-atherogenic properties. ADPN levels are elevated in ESRD but it has been reported that ESRD patients with low plasma ADPN levels have a high risk of cardiovascular death. OBJECTIVE: To clarify the atherosclerotic risk and especially the significance of ADPN levels in pediatric patients on CPD. DESIGN: Cross-sectional studyin the pediatric peritoneal dialysis unit of a university hospital. PATIENTS: 18 children, aged 12.6 +/- 5.6 years, being treated with CPD and 20 healthy age- and sex-matched control subjects were enrolled in this study. METHODS: Serum ADPN levels and other risk factors, including blood pressure, blood glucose, serum lipid/lipoprotein fractions, apolipoprotein B, C-reactive protein (CRP), lipoprotein(a), and homocysteine levels, were studied in CPD patients and compared to the controls. RESULTS: Serum ADPN levels were three times higher in the CPD group compared to the control subjects, as was previously reported. Apolipoprotein B and CRP levels were also high in the CPD group. No significant difference was found in other atherosclerotic parameters, including lipoprotein(a) and homocysteine levels. Interestingly, we found a negative correlation between log ADPN and creatinine levels among the CPD patients (r = -0.54, p < 0.05). There was no correlation between log ADPN and duration of CPD. Creatinine and low-density lipoprotein levels could account for 54% of the total variation in ADPN levels. CONCLUSION: Among pediatric CPD patients, serum levels of the anti-atherogenic protein, ADPN, were inversely associated with creatinine. ADPN level might be a novel marker to predict prognosis in pediatric CPD patients.  相似文献   
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Smith E  Yang J  McGann L  Sebald W  Uludag H 《Biomaterials》2005,26(35):7329-7338
The purpose of this study was to design thermoreversible biomaterials for enhanced adhesion of bone morphogenetic protein-2 (BMP-2)-responsive cells. Peptides containing the arginine-glycine-aspartic acid (RGD) sequence were conjugated to N-isopropylacrylamide (NiPAM) polymers via amine-reactive N-acryloxysuccinimide (NASI) groups. In monolayer cultures, the adhesion of BMP-2-responsive C2C12 cells to RGD-grafted NiPAM/NASI surfaces was significantly higher than adhesion on ungrafted NiPAM/NASI surfaces. Although the morphology of cells adhered to RGD-grafted NiPAM/NASI surfaces was comparable to cells adhered on tissue culture polystyrene (TCPS), long-term cell growth was limited on the NiPAM/NASI surfaces, even for RGD-grafted surfaces. Treatment of C2C12 cells with recombinant BMP-2 induced dose-dependent osteoblastic differentiation as assessed by alkaline phosphatase (ALP) activity. In the absence of BMP-2, cells cultured on NiPAM/NASI polymers (either grafted with RGD peptide or not) expressed significantly higher levels of ALP activity than the cells cultured on TCPS, indicating that the polymer surfaces induced some osteoblastic activity in C2C12 cells without the need for BMP-2. We conclude that NiPAM-based thermoreversible biomaterials, despite their limited ability to support cell growth, allowed an enhanced expression of the chosen osteogenic marker (ALP) by C2C12 cells in vitro.  相似文献   
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The prevalences of deficiencies in antithrombin III (AT III), protein C (PC), protein S (PS) and in the activated protein C (APC) resistance in the thrombotic population of the Trakya region, Turkey were investigated. 37 patients with venous thrombosis (VT) and 17 patients with arterial thrombosis (ArT) were included in this study. The mean ages of the patients with VT and ArT were 46 years (range 20-70) and 38 years (range 32-40), respectively. The activity of AT III was measured by commercially available immuno-turbidimetric assay. The activities of PC and PS were determined by coagulometric assay. The APC resistance was measured using a modified APTT-based clotting assay. Among the VT patients, there were 2 cases (5.4%) with AT III, 5 (13.51%) with PC deficiency, 5 (13.51%) with PS deficiency and 2 (5.4%) with APC resistance. In the ArT patient group, there was 1 patient (5.88%) with AT III, 3 (17.64%) with PC deficiency, 1 (5.88%) with PS deficiency and no APC resistant patients, while there was one (2.08%) with PC deficiency and one (2.08%) with APC resistance in the control group (49 persons, mean age 41 years). The relative risk of thrombosis (odds ratio) was 1.7 in the deficiency of PC and 5.6 in the deficiency of PS. The data presented suggests that the prevalences of AT III, PC and PS deficiencies causing thrombophilia in the Trakya region of Turkey are higher than in other reported studies while the APC resistance is lower than in others. Further studies including more patients would be required to clarify these discrepancies.  相似文献   
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BACKGROUND: Our main aim was to investigate the effects of melatonin (ME), possibly the most powerful free-radical scavenger, on the prevention of i.p. adhesion formation in rat uterine horn. Our secondary aim was to determine whether different methods of administration of ME were beneficial. METHODS: Animals were randomly assigned into seven groups, each consisting of 13 rats. Measured serosal injury was created using a standard technique. While control and two sham groups were not given ME, two of the remaining four groups were given a single dose of 10 mg/kg (2 mg) of ME i.p. immediately after injury and 30 min prior to injury respectively. In the two other groups, ME treatment was continued daily for 5 days. All animals were killed 2 weeks after surgery and adhesions were determined and scored by a examiner blinded to the test. RESULTS: The extent, severity and total scores of adhesion were found to be significantly reduced in all of the ME treatment groups when compared with control and sham groups. There were no statistically significant differences between the treatment groups. CONCLUSIONS: This study showed that even single dose ME therapy was effective in the prevention of post- operative i.p. adhesion formation.  相似文献   
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