Effects of Delayed Finishing/Polishing on Surface Roughness, Hardness and Gloss of Tooth-Coloured Restorative Materials

Objectives: The aim of this study was to investigate the effect of delayed finishing/polishing on the surface roughness, hardness and gloss of tooth-coloured restorative materials. Methods: Four different tooth-coloured restoratives: a flowable resin composite- Tetric Flow, a hybrid resin composite- Venus, a nanohybrid resin composite- Grandio, and a polyacid modified resin composite- Dyract Extra were used. 30 specimens were made for each material and randomly assigned into three groups. The first group was finished/polished immediately and the second group was finished/polished after 24 hours. The remaining 10 specimens served as control. The surface roughness of each sample was recorded using a laser profilometer. Gloss measurements were performed using a small-area glossmeter. Vickers microhardness measurements were performed from three locations on each specimen surface under 100g load and 10s dwell time. Data for surface roughness and hardness were analyzed by Kruskal Wallis test and data for gloss were subjected to one-way ANOVA and Tukey test (P .05). The lowest hardness values were found under Mylar strip. Delayed finishing/polishing significantly increased the hardness of all materials. Conclusions: The effect of delayed finishing/polishing on surface roughness, gloss and hardness appears to be material dependent.PubMe

Effects of Ambient Air Pollution on Hemostasis and Inflammation

BACKGROUND: Air pollution has consistently been associated with increased morbidity and mortality due to respiratory and cardiovascular disease. Underlying biological mechanisms are not entirely clear, and hemostasis and inflammation are suggested to be involved. OBJECTIVES: Our aim was to study the association of the variation in local concentrations of airborne particulate matter (PM) with aerodynamic diameter < 10 mu m, carbon monoxide, nitrogen monoxide, nitrogen dioxide, and ozone with platelet aggregation, thrombin generation, fibrinogen, and C-reactive protein (CRP) levels in healthy individuals. METHODS: From 40 healthy volunteers, we collected 13 consecutive blood samples within a 1-year period and measured light-transmittance platelet aggregometry, thrombin generation, fibrinogen, and CRP. We performed regression analysis using generalized additive models to study the association between the hemostatic and inflammatory variables, and local environmental concentrations 0 air pollutants for time lags within 24 hr before blood sampling or 24-96 hr before blood sampling. RESULTS: In general, air pollutants were associated with platelet aggregation [average, +8% per interquartile range (IQR), p < 0.01] and thrombin generation (average, +1% per IQR, p < 0.015). Platelet aggregation was not affected by in vitro incubation of plasma with PM. We observed no relationship between any of the air pollutants and fibrinogen or CRP levels. CONCLUSIONS:. Air pollution increased platelet aggregation as well as coagulation activity but had no clear effect on systemic inflammation. These prothrombotic effects may partly explain the relationship between air pollution and the risk of ischemic cardiovascular disease

Evaluation of organ weights and ventricular thicknesses in electrocution related deaths based on autopsy reports: a biophysical approach

Objective: To evaluate autopsy reports of the deaths due to electrocution in terms of body mass index, body surface area, and organ weights with a biophysical perspective. Method: The retrospective study was conducted in Malatya, Turkey, and comprised autopsy reports of electrocution cases that were obtained from the local branch of the Council of Forensic Medicine related to the period from 2012 to 2019. Organ weights and ventricular thicknesses were compared in terms of body mass index and body surface area. Electrical marks were also evaluated in detail. Data was analysed using SPSS 18. Results: Of the 45 cases, 36(%) were male and 9(%) were female. The overall mean age was mean age of 39±13 years (range: 20-71 years). There were no significant differences in organ weights and ventricular thicknesses in different body mass index groups (p>0.05). The weights of head and heart were significantly different in relation to body surface area (p0.05). Conclusion: Comparing the organ weights in electrocution autopsies to normal organ weights may help decide the cause of death. During autopsy, electrical marks should be evaluated by considering the characteristics of the electrical current. Key Words: Electrocution, BMI, BSA, Organ weights

An Adaptive Element-Level Impedance-Matched ASIC With Improved Acoustic Reflectivity for Medical Ultrasound Imaging

This paper presents an active impedance matching scheme that tries to optimize electrical power transfer and acoustic reflectivity in ultrasound transducers. Leveraging negative capacitance-based impedance matching would potentially improve the bandwidth and electrical power transfer while minimizing acoustic reflection of transducer elements and improve uniformity while reducing acoustic crosstalk of transducer arrays. A 16-element transceiver front-end is designed which employs an element-level active capacitive impedance cancellation scheme using an element-level negative impedance converter. The ASIC fabricated in 180-nm HVBCD technology provides high-voltage pulses up to 60 V consuming 3.6 mW and occupying 2.5 mm2. The front-end ASIC is used with a 1-D capacitive micromachined ultrasonic transducer (CMUT) array and its acoustical reflectivity reduction and imaging capabilities have successfully been demonstrated through pulse-echo measurements and acoustic imaging experiments

EFFECTS OF ACUTE MODERATE AND STRENUOUS EXERCISE BOUTS ON IL-17 PRODUCTION AND INFLAMMATORY RESPONSE IN TRAINED RATS

In this study, we aimed to compare the effects of a single bout of acute moderate and strenuous running exercise on the production of interleukin-17 (IL-17), interleukin-6 (IL-6), interleukin-1 receptor antagonist (IL-1ra) and inflammatory response of skeletal muscles in regularly trained rats. Eight week old rats were trained by treadmill running 5 days per week for 13 weeks at the durations of 30 min (moderate) and 60 min (strenuous). Two days after the last training session, the animals were subjected to a single bout of moderate or strenuous exercise and serum samples were analyzed for IL-17, IL-6, IL-1ra levels and myeloperoxidase (MPO) activity of gastrocnemius muscle were determined. IL-17 level significantly increased in strenuous exercise group when compared to that of sedentary controls (p < 0.01), On the other hand, only in the moderate exercise group, there was a negative correlation between IL-6 and IL-17 levels (r = - 0.857 and p = 0.014). In conclusion, acute single bout of strenuous exercise increased IL-17 production in trained rats and, this cytokine may be involved in inflammatory process of skeletal muscle

Plasma viscosity and mean platelet volume in patients undergoing coronary angiography

Background: Markers of platelet activation and haemorrheological indices have been demonstrated to play a role in the pathophysiology of atherosclerosis and cardiovascular events. In this study, we aimed at investigate the association between plasma viscosity and platelet indices in patients undergoing coronary angiography. Materials and methods: Three hundred and eighty four consecutive patients scheduled to undergo coronary angiography were included in the study. Prior to coronary angiography, blood samples were withdrawn to determine routine biochemical markers, blood cell analyses and viscosity measurements. According to the results of coronary angiography, patients were classified either in a subgroup with coronary artery disease (CAD; 1 or more stenoses &gt; 50%) or normal coronary arteries (NCA; no stenoses or &lt;50%). Results: There was a statistically significant correlation between plasma viscosity and mean platelet volume levels in all patients undergoing coronary angiography (r = 0.199, p &lt;0.001). Additionally, when correlation analysis was performed within each group, plasma viscosity significantly correlated with MPV both in patients with CAD (r = 0.18, p = 0.004) and in patients with NCAs (r = 0.272, p = 0.002). Linear regression analysis revealed that plasma viscosity was positively associated with MPV while platelet number was inversely but significantly associated with MPV. Conclusion: We have shown for the first time that MPV correlates with plasma viscosity in patients undergoing coronary angiography, suggesting a relation with plasma proteins and activation of circulating platelets or peripheral consumption of platelets. To evaluate this relation further controlled studies also in patients with acute coronary syndromes are warranted

Early Atherosclerosis Exhibits an Enhanced Procoagulant State

Background-Thrombin generation in vivo may be important in regulating atherosclerotic progression. In the present study, we examined for the first time the activity and presence of relevant coagulation proteins in relation to the progression of atherosclerosis. Methods and Results-Both early and stable advanced atherosclerotic lesions were collected pairwise from each individual (n=27) during autopsy. Tissue homogenates were prepared from both total plaques and isolated plaque layers, in which the activity of factors (F) II, X, and XII and tissue factor was determined. Microarray analysis was implemented to elucidate local messenger RNA synthesis of coagulation proteins. Part of each specimen was paraffin embedded, and histological sections were immunohistochemically stained for multiple coagulation markers with the use of commercial antibodies. Data are expressed as median (interquartile range [IQR]). Tissue factor, FII, FX, and FXII activities were significantly higher in early atherosclerotic lesions than in stable advanced atherosclerotic lesions. Endogenous thrombin potential and thrombin-antithrombin complex values consolidated a procoagulant profile of early atherosclerotic lesions (endogenous thrombin potential, 1240 nmol/L.min [IQR, 1173 to 1311]; thrombin-antithrombin complex, 1045 ng/mg [IQR, 842.6 to 1376]) versus stable advanced atherosclerotic lesions (endogenous thrombin potential, 782 nmol/L.min [IQR, 0 to 1151]; thrombin-antithrombin complex, 718.4 ng/mg [IQR, 508.6 to 1151]). Tissue factor, FVII, and FX colocalized with macrophages and smooth muscle cells. In addition, multiple procoagulant and anticoagulant proteases were immunohistochemically mapped to various locations throughout the atherosclerotic vessel wall in both early and advanced atherosclerotic stages. Conclusions-This study shows an enhanced procoagulant state of early-stage atherosclerotic plaques compared with advanced-stage plaques, which may provide novel insights into the role of coagulation during atherosclerotic plaque progression. (Circulation. 2010;122:821-830.