Irisin: a potentially candidate marker for myocardial infarction.

Myocardial infarction (MI) causes energy depletion through imbalance between coronary blood supply and myocardial demand. Irisin produced by the heart reduces ATP production by increasing heat generation. Energy depletion affects irisin concentration in circulation and cardiac tissues, suggesting an association with MI. We examined: (1) irisin expression immunohistochemically in rat heart, skeletal muscle, kidney and liver in isoproterenol (ISO)-induced MI, and (2) serum irisin concentration by ELISA. Rats were randomly allocated into 6 groups (n=6), (i) control, (ii) ISO (1h), (iii) ISO (2h), (iv) ISO (4h), (v) ISO (6h), and (vi) ISO (24h), 200mg ISO in each case. Rats were decapitated and the blood and tissues collected for irisin analysis. Blood was centrifuged at 1792 g for 5 min. Tissues were washed with saline and fixed in 10% formalin for histology. Serum irisin levels gradually decreased from 1h to 24h in MI rats compared with controls, the minimum being at 2h, increasing again after 6h. Cardiac muscle cells, glomerular, peritubular renal cortical interstitial cells, hepatocytes and liver sinusoidal cells and perimysium, endomysium and nucleoi of skeletal muscle were irisin positive, but its synthesis decreased 1-4h after MI. At all time-points, irisin increased near myocardial connective tissue, with production in skeletal muscle, liver and kidney recovering after 6h, although slower than controls. Unique insight into the pathogenesis of MI is shown, and the gradually decrease of serum irisin might be a diagnostic marker for MI.

Examination of the prevalence of periapical lesions and technical quality of endodontic treatment in a Turkish subpopulation.

OBJECTIVE: The objective of this study was to investigate the prevalence of periapical lesions by evaluating the periapical status and to evaluate the relationship between the technical quality of endodontic treatments and presence of periapical lesions in a Turkish subpopulation. STUDY DESIGN: A total of 11,542 teeth of 438 patients were radiographically evaluated. Presence of endodontic treatment and obturation levels, coronal restorations, and degree of root canal curvature angles were noted. Apical status was assessed by the Periapical Index Scores (PAI). The χ(2) test was used for statistical analysis. RESULTS: Among all teeth, 179 (1.55%) had endodontic treatment and 189 (1.63%) had periapical lesions. Of 179 endodontically treated teeth, 68 (37.99%) had periapical lesions. The prevalence of periapical lesions was found to be significantly high among underfilled teeth (P < .001). In most underfilled teeth, the presence of severe curvatures was particularly of interest. Prevalence of inadequate coronal restorations was significantly high among the teeth with periapical lesions, whether endodontically treated or not (P < .001). CONCLUSIONS: The findings of the present study indicate that considerable effort should be spent by dental practitioners to improve the technical quality of root canal fillings.