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Due to the high computational costs of the Eulerian multiphase model, which solves the conservation equations for each considered phase, a two-phase mixture model is proposed to reduce these costs in the current study. Only one single equation for each the momentum and enthalpy equations has to be solved for the mixture phase. The Navier–Stokes and energy equations were solved using the 3D finite volume method. The model was used to simulate the liquid–solid phase transformation of a Fe-0.82wt%C steel alloy under the effect of both thermocapillary and buoyancy convections. The alloy was cooled in a rectangular ingot (100 × 100 × 10 mm3) from the bottom cold surface to the top hot free surface by applying a heat transfer coefficient of h = 600 W/m2/K, which allows for heat exchange with the outer medium. The purpose of this work is to study the effect of the surface tension on the flow and segregation patterns. The results before solidification show that Marangoni flow was formed at the free surface of the molten alloy, extending into the liquid depth and creating polygonized hexagonal patterns. The size and the number of these hexagons were found to be dependent on the Marangoni number, where the number of convective cells increases with the increase in the Marangoni number. During solidification, the solid front grew in a concave morphology, as the centers of the cells were hotter; a macro-segregation pattern with hexagonal cells was formed, which was analogous to the hexagonal flow cells generated by the Marangoni effect. After full solidification, the segregation was found to be in perfect hexagonal shapes with a strong compositional variation at the free surface. This study illuminates the crucial role of surface-tension-driven Marangoni flow in producing hexagonal patterns before and during the solidification process and provides valuable insights into the complex interplay between the Marangoni flow, buoyancy convection, and solidification phenomena. [ABSTRACT FROM AUTHOR]

Research efforts have been dedicated to predicting microstructural evolution during solidification processes. The main secondary arm spacing controls the mushy zone's permeability. The aim of the current work was to build a simple sub-grid model that describes the growth and coarsening of secondary side dendrite arms. The idea was to reduce the complexity of the curvature distribution with only two adjacent side arms in concurrence. The model was built and applied to the directional solidification of Al-06wt%Cu alloy in a Bridgman experiment. The model showed its effectiveness in predicting coarsening phenomena during the solidification of Al-06wt%Cu alloy. The results showed a rapid growth of both arms at an earlier stage of solidification, followed by the remelting of the smaller arm. In addition, the results are in good agreement with an available time-dependent expression which covers the growth and coarsening. Such model can be implemented as a sub-grid model in volume average models for the prediction of the evolution of the main secondary arms spacing during macroscopic solidification processes. [ABSTRACT FROM AUTHOR]

Secondary dendrite arm spacing (SDAS) is one of the most important factors affecting macrosegregation and mechanical properties in solidification processes. Predicting SDAS is one of the major parameters in foundry technology. In order to predict the evolution of microstructures during the solidification process, we proposed a simple model which predicted the secondary dendrite arm spacing based solely on the tip velocity (related to the tip supersaturation) and cooling rate. The model consisted of a growing cylinder inside a liquid cylindrical envelope. Two important hypotheses were made: (1) Initially the cylinder radius was assumed to equal the dendrite tip radius and (2) the cylindrical envelope had a fixed radius in the order of the dendrite tip diffusion length. The numerical model was tested against experiments using various Pb–Sn alloys for a fixed temperature gradient. The results were found to be in excellent agreement with experimental measurements in terms of SDAS and dendrite tip velocity prediction. This simple model is naturally destined to be implemented as a sub-grid model in volume-averaging models to predict the local microstructure, which in turn directly controls the mushy zone permeability and macrosegregation phenomena. [ABSTRACT FROM AUTHOR]

Background: We tried to understand roles of systemic disorders in the pathophysiology of rheumatic heart disease (RHD). Methods: All patients who applied to the Internal Medicine Units were included. Results: We detected 29 females and 20 males with RHD. Their mean ages were 42.7 versus 33.0 years, respectively (p= 0.016). There were 26 cases with sickle cell diseases (SCDs), two cases with rheumatoid arthritis (RA), two cases with systemic lupus erythematosus (SLE), one case with juvenile rheumatoid arthritis (JRA), one case with common variable immunodeficiency, one case with celiac sprue, two cases with cirrhosis, and one case with chronic renal disease. In other words, there were associated systemic pathologies in 73.4% of RHD patients. Mitral valve was involved in 41.3%, mitral and aortic valves were involved in 26.0%, mitral and tricuspid valves were involved in 17.3%, aortic valve was involved in 8.6%, and all of the three valves were involved in 6.5% of the cases. In another definition, mitral, aortic, and tricuspid valves were involved in 91.3%, 41.3%, and 23.9% of cases, respectively. Interestingly, tricuspid valve was never involved alone, instead always together with mitral valve. There were 69.3% of patients with mitral regurgitation, 26.5% with aortic regurgitation, 22.4% with tricuspid regurgitation, 20.4% with mitral stenosis, and 18.3% with aortic stenosis. Conclusion: Systemic disorders including SCDs, RA, SLE, and JRA induce chronic inflammatory processes on vascular endothelium in the whole body, and terminate with an immunosuppression by several mechanisms that may be the cause of higher prevalence of RHD together with such disorders. [ABSTRACT FROM AUTHOR]

Purulent pericardial effusion, although rare, is a life-threatening condition usually produced by the extension of a nearby bacterial infection locus or by blood dissemination in the immune-suppressed subjects or in the course of cardiothoracic surgery. Because clinical features of purulent pericardial effusion are often nonspecific, it can cause delay in diagnosis. Therefore, a high index of suspicion is required for timely diagnosis and management. Herein, we describe a case of giant purulent pericardial effusion due to Streptococcus intermedius with the history of bronchiectasis and pneumonia, which was successfully treated with pericardiocentesis via parasternal approach, appropriate antibiotics, and pericardiectomy. [ABSTRACT FROM AUTHOR]

In this work, the design, micro-fabrication, and characterization steps of a contactless linear accelerator is presented. The proposed design in principle can levitate conductive micro-objects and accelerate or move them over a predefined trajectory. The levitation is realized using electromagnetic induction generated by a changing AC field whereas the propulsion is achieved through electrostatic forces from a controlled DC source. This is the first time in literature that such a hybrid design is used to accomplish this idea. It has been experimentally shown that the proposed design can levitate 1 mm × 1 mm sized and 7 μm thick micro-objects to a maximum height of 75 μm and propel them forward continuously at a maximum average forward velocity of 3.6 mm/s. [ABSTRACT FROM AUTHOR]

Absence of the left circumflex coronary artery (LCX) is a very rare coronary anomaly. The anomaly has been reported in only 0.003% of all patients who underwent routine coronary angiography. Although rare, the failure to visualize a coronary artery in its expected anatomical location might cause life-threatening complications such as total occlusion with acute coronary syndromes. In the present paper, we report a patient with absent LCX and discuss the previously reported cases in terms of diagnostic and clinical importance, association with atherosclerosis and other anomalies. We searched Medline (www.ncbi.nlm.nih.gov) for cases of absent LCX and found that so far absence of LCX has been reported 27 times and in 32 cases. Here in this case report and minireview we discuss the characteristics of the present case and previous 32 cases with absence of LCX. The majority of the patients were over 30 years old at the time of diagnosis and the condition is more common in females. Although absence of LCX is generally considered as a benign entity, it might be atherosclerotic and can cause acute coronary syndromes including myocardial infarction and be associated with other anomalies. Proper diagnosis of the absence of LCX is very important because it can be misinterpreted as a totally occluded LCX. In subjects with absent LCX, infarction in the superdominant RCA might be more dangerous. It is more common in females and although conventional coronary angiography is the most widely used diagnostic modality, multidetector computed tomography might also be helpful. [ABSTRACT FROM AUTHOR]

In this paper, a mechanical amplification concept for microelectromechanical systems (MEMS) physical sensors is proposed with the aim to improve their sensitivity. The scheme is implemented using a system of micromachined levers (microlevers) as a deflection amplifying mechanism. The effectiveness of the mechanism is demonstrated for a capacitive accelerometer. A proof-of-concept single-axis mechanically amplified accelerometer with an amplification factor of 40 has been designed, simulated, and fabricated, and results from its evaluation are presented in this paper. The sensor's amplified output has a sensitivity of 2.39 V/g using an open-loop capacitive pick-off circuit based on charge amplifiers. Experimental results show that the addition of the mechanical amplifier does not alter the noise floor of the sensor. The measured natural frequency of the first mode of the sensor is at 734 Hz, and the full-scale measurement range is up to 7 g with a maximum nonlinearity of 2\%. It is shown, through comparison with a conventional design, that the mechanically amplified accelerometer provides higher deflection without sacrificing bandwidth.\hfill[2011-0231] [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a full wafer, dicing free, dry release process for MEMS silicon-on-insulator (SOI) sensors and actuators. The developed process is particularly useful for inertial sensors that benefit from a large proof mass, for example accelerometers and gyroscopes. It involves consecutive front and backside deep reactive ion etching (DRIE) of the substrate to define the device features, release holes, and trenches. This is followed by hydrofluoric acid vapor phase etching (HF VPE) to release the proof mass and the handle wafer underneath to allow vertical displacements of the proof mass. The release process also allows the devices to be detached from each other and the substrate without the need of an extra dicing step that may damage the delicate device features or create debris. In the work described here, the process is demonstrated for the full wafer release of a high performance accelerometer with a large proof mass measuring 4×7mm2. The sensor was successfully fabricated with a yield of over 95%. [Copyright &y& Elsevier]

Abstract: Objective: Recent studies have suggested that nuts have favorable effects beyond lipid lowering. We aimed to investigate effect of the Antep pistachio (Pistacia vera L.) on blood glucose, lipid parameters, endothelial function, inflammation, and oxidation in healthy young men living in a controlled environment. Methods: A Mediterranean diet was administered to normolipidemic 32 healthy young men (mean age 22 y, range 21–24) for 4 wk. After 4 wk, participants continued to receive the Mediterranean diet but pistachio was added for 4 wk by replacing the monounsaturated fat content constituting ≈20% of daily caloric intake. Fasting blood samples and brachial endothelial function measurements were performed at baseline and after each diet. Results: Compared with the Mediterranean diet, the pistachio diet decreased glucose (P <0.001, −8.8±8.5%), low-density lipoprotein (P <0.001, −23.2±11.9%), total cholesterol (P <0.001, −21.2±9.9%), and triacylglycerol (P =0.008, −13.8±33.8%) significantly and high-density lipoprotein (P =0.069, −3.1±11.7%) non-significantly. Total cholesterol/high-density lipoprotein and low-density lipoprotein/high-density lipoprotein ratios decreased significantly (P <0.001 for both). The pistachio diet significantly improved endothelium-dependent vasodilation (P =0.002, 30% relative increase), decreased serum interleukin-6, total oxidant status, lipid hydroperoxide, and malondialdehyde and increased superoxide dismutase (P <0.001 for all), whereas there was no significant change in C-reactive protein and tumor necrosis factor-α levels. Conclusion: In this trial, we demonstrated that a pistachio diet improved blood glucose level, endothelial function, and some indices of inflammation and oxidative status in healthy young men. These findings are in accordance with the idea that nuts, in particular pistachio nuts, have favorable effects beyond lipid lowering that deserve to be evaluated with prospective follow-up studies. [Copyright &y& Elsevier]

This paper presents a microelectromechanical-system-based electromagnetic vibration-to-electrical power generator that can harvest energy from low-frequency external vibrations. The efficiency of vibration-based harvesters is proportional to excitation frequency, so the proposed generator is designed to convert low-frequency environmental vibrations to a higher frequency by employing the frequency upconversion (FupC) technique. It has been shown that the generator can effectively harvest energy from environmental vibrations of 70-150 Hz and generates 0.57-mV voltage with 0.25-nW power from a single cantilever by upconverting the input vibration frequency of 95 Hz-2 kHz. The fabricated generator size is 8.5×7×2.5 mm3, and a total of 20 serially connected cantilevers have been used to multiply the generated voltage and power. The generator demonstrated in this paper is designed for the proof of concept, and the power and voltage levels can further be increased by increasing the number of cantilevers or coil turns. The performance of the generator is also compared with that of a same-sized custom-made traditional magnet-coil-type generator and with that of a traditional generator from the literature to prove its effectiveness. [ABSTRACT FROM AUTHOR]

Abstract: Background: Diabetes mellitus (DM) is accepted as coronary heart disease equivalent even in the presence of normal coronary artery on coronary angiography. We aimed to evaluate microvascular circulation with novel angiographic perfusion indexes “myocardial blush grade” (MBG) and “myocardial filling time” (MFT) in patients with uncomplicated DM. Methods: Among 4563 angiographic studies performed between November 2001 and May 2004, 70 subjects with DM who were normotensive, non-smokers and with normal lipid profiles were recruited into the study. Patients were divided into 2 groups according to angiographic results. DM-1: diabetic normotensive and normolipidemic subjects with normal coronary angiography (n: 30) and DM-2: diabetic subjects with lesions in the left anterior descending artery (LAD) less than 50% (n: 40). Non-diabetic, normotensive and normolipidemic 60 subjects were assigned as the control group. Control group was also divided into 2 groups according to angiographic results Control-1: subjects with normal coronary angiography (n: 30) and ; Control-2: subjects with lesions in the left anterior descending artery (LAD) less than 50% (n: 30). MBG was defined between 0 and 3 according to myocardial dyeing density and wash-out speed with 0 as the least and 3 as the most. MFT was calculated by conversion of the frame count, from the beginning of myocardial blushing till the time with the highest amount of contrast, to milliseconds. Results: MFT was longer in the group DM-2 when compared with other groups (p <0.0001). MFT was similar in Control-2 and DM-1. MFT was shorter in Control-1 when compared with DM-1 and DM-2 (p <0.0001). MBG was lower in DM-2 when compared with Control-1 and Control-2 (p =0.001). However MBG was similar in DM-1 when compared with Control-1 and Control-2. Conclusions: Microvascular function is worse in subjects with both diabetes and coronary artery disease than in non-diabetic subjects with coronary artery disease. The most impressive result of our study is diabetic patients with normal coronary angiography have similar MBG and MFT results with non-diabetic coronary artery disease patients. DM causes microvascular dysfunction even one has normal coronary angiography and this put them in the same risk group with non-diabetic coronary artery patients. [Copyright &y& Elsevier]

Abstract: This paper presents a wideband electromagnetic vibration-to-electrical micro power generator. The micro generator is capable of generating steady power over a predetermined frequency range. Power is generated by means of the relative motion between a magnet and coils fabricated over resonating cantilevers through electromagnetic induction. The reported generator covers a wide band of external vibration frequency by implementing a number of serially connected cantilevers in different lengths resulting in an array of cantilevers with varying natural frequencies. The device generates 0.4μW of continuous power with 10mV voltage in an external vibration frequency range of 4.2–5kHz, covering a band of 800Hz. [Copyright &y& Elsevier]

We investigated the association between chronic carbon monoxide (CO) exposure and electrocardiographic maximum/minimum P-wave duration (Pmax/Pmin), P-wave dispersion (Pd), maximum/minimum QT interval (QTmax/QTmin), and QT and corrected QT dispersion (QTd/cQTd), which are known as predictors of atrial fibrillation, ventricular arrhythmias, and sudden death. We obtained electrocardiograms of 48 apparently healthy male indoor barbecue workers (age mean ± SD; 33.6 ± 9.4) who were working in various restaurants for at least 3 yr and 51 age-matched healthy men (age mean ± SD; 35.1 ± 6.7). Average working time of the indoor barbecue workers in their jobs was 15.6 ± 7.1 yr. P-wave parameters were analyzable in 39 barbecue workers and 40 control subjects and QT intervals were analyzable in 44 barbecue workers and 47 control subjects. Clinical characteristics of indoor barbecue workers and the control group were comparable in terms of age, sex, body mass index, blood pressure, heart rate, Pmin, and QTmin. However, COHb levels, Pmax, Pd, QTmax, QTd, and cQTd measurements were higher in indoor barbecue workers than in the control group (6.48 ± 1.43 vs. 2.19 ± 1.30, p < .001; 106.15 ± 7.47 vs. 101.50 ± 6.62, p < .005; 30.51 ± 7.59 vs. 24.50 ± 6.77, p < .001; 406.59 ± 17.64 vs. 390.85 ± 13.15, P < .001; 48.40 ± 8.87 vs. 34.89 ± 5.85, P < .001; 53.64 ± 9.14 vs. 37.77 ± 6.71, P < .001, respectively). In Pearson correlation analysis there were significant correlations between COHb level and Pd, QTmax, QTd, and cQTd (r = .315 P < .005; r = .402, P < .001, r = .573, P < .001, r = .615, P < .001, respectively). In conclusion, the present study is the first to assess and find an association between chronic CO exposure and electrocardiographic Pd and QTd/cQTd. [ABSTRACT FROM AUTHOR]

Background: Sleep deprivation (SD) is associated with worse cardiovascular outcome including mortality. Prolonged P-wave duration and P-wave dispersion (Pd) are known to represent inhomogeneous conduction of sinus impulses and are known to be electrophysiologic predictors of atrial fibrillation. Pd in normal subjects has been reported to be influenced by the autonomic tone. Because autonomic tone is affected by sleep and sleep duration, we evaluated the effect of acute SD on P-wave duration and Pd in healthy young adults and whether the effect was gender selective. Methods : We obtained electrocardiograms of 37 healthy young volunteers (age: 28.45 ± 7.97; 11 women) after a night of regular sleep and repeated after a night with sleep debt. We measured minimum and maximum P-wave durations (Pmin, Pmax) and Pd in milliseconds. Results : Average sleep time of the subjects were 7.7 ± 0.8 hours during regular sleep and 1.7 ± 1.6 hours during a night of sleep debt (P < 0.001). Subjects had significantly lower values of Pmin in milliseconds after a night of sleep debt when compared to regular sleep (65.13 ± 8.03 vs 74.86 ± 10.95; P < 0.001), whereas they had significantly higher values of Pmax and Pd (102.16 ± 9.46 vs 95.13 ± 11.21; P < 0.001 and 37.02 ± 8.11 vs 20.27 ± 11.42; P < 0.001, respectively). In Pearson's correlation analysis Pmin was positively and Pmax and Pd were negatively correlated with sleep time (P < 0.001, r = 0.465; P = 0.003, r =−0.336 and P < 0.001, r =–0.698 respectively). Effect of SD on P-wave duration and Pd was similar for both men and women. Conclusions : In conclusion, prolongation of Pmax and Pd in acute SD suggests that acute SD might contribute to development and/or recurrence of atrial fibrillation. [ABSTRACT FROM AUTHOR]

Abstract: Objective: We tested the hypothesis that simultaneous inhibition of the endothelial integrin αvβ3 and the platelet glycoprotein IIb/IIIa receptor will substantially reduce infarct size in a model of acute coronary thrombosis and primary angioplasty. Methods: Dogs were subjected to thrombus formation in the left anterior descending coronary artery followed by primary angioplasty. Prior to angioplasty, they were randomized into 3 treatment groups. Group 1 (n=7) received saline; Group 2 (n=9) received MK-383 that inhibits only IIb/IIIa; and Group 3 (n=9) received CP-4715, that inhibits both IIb/IIIa and αvβ3. Results: There was a 59% reduction in infarct size in dogs receiving CP-4715 compared to controls (p=0.002) and a 37% reduction compared to the dogs receiving MK-383 (p=0.04). Myocardium microthrombi were seen to be reduced similarly with both drugs on post-mortem 99mTc-DMP444 autoradiography that reflects in vivo IIb/IIIa receptor activity. In vivo imaging using echistatin-conjugated and leukocyte-targeted microbubbles revealed significant αvβ3 inhibition and reduction in active leukocyte recruitment only in Group 3 dogs. Myocardial blood flow and regional function after reperfusion were also significantly better in this group. Conclusion: Simultaneous inhibition of IIb/IIIa and αvβ3 causes a marked reduction in infarct size in a model of acute coronary thrombosis and primary PTCA that is associated with reduced myocardial microthrombi and inflammation, as well as improved myocardial blood flow and regional function. These results may have important implications in the treatment of acute coronary syndromes. [Copyright &y& Elsevier]

Objectives: We sought to determine whether the severity of peripheral arterial disease (PAD) can be assessed by measuring blood flow reserve in limb skeletal muscle with contrast-enhanced ultrasound (CEU). Background: Noninvasive imaging of distal limb perfusion could improve management of patients with PAD by evaluating the impact of large and small vessel disease, and collateral flow. Methods: In 12 dogs, blood flow in the quadriceps femoris was measured by CEU at rest and during either electrostimulated contractile exercise or adenosine infusion. Femoral artery blood flow was measured by Doppler ultrasound. Studies were performed in the absence and presence of either moderate or severe stenosis (pressure gradient of 10 to 20 mm Hg and >20 mm Hg, respectively). Results: Resting femoral artery blood flow progressively decreased with stenosis severity, while resting skeletal muscle flow was reduced only with severe stenosis (52 +/- 21% of baseline, p < 0.05), indicating the presence of collateral flow. Skeletal muscle flow reserve during contractile exercise or adenosine decreased incrementally with increasing stenosis severity (p < 0.01). The stenotic pressure gradient correlated with skeletal muscle flow reserve for exercise and adenosine (r = 0.70 for both, p < 0.01). Conclusions: Contrast-enhanced ultrasound of limb skeletal muscle can be used to assess the severity of PAD by measuring muscle flow reserve during either contractile exercise or pharmacologic vasodilation. Unlike currently used methods, this technique may provide a measure of the physiologic effects of large- and small-vessel PAD, and the influence of collateral perfusion. [ABSTRACT FROM AUTHOR]

Despite its safety and efficacy, the traumatic effects of high-energy shock waves (HESW) on renal morphology and function during long-term follow-up have yet to be elucidated. Although the main target of shock waves is the stone located in the kidney, the surrounding tissue and other organs are also subjected to trauma during this procedure. In contrast to renal blood flow evaluation after shock wave treatment, ischemic development, causing varying degrees of damage at the tissue level, has not been well evaluated. . The renoprotective peptide adrenomedullin (AM) is a potent vasorelaxing, natriuretic and cell growth modulating peptide, which is thought to act as an autocrine/paracrine regulator in renal glomeruli and tubules. In this experimental study, renal parenchymal AM levels were assessed in an attempt to evaluate the effect of HESW on the tissue levels of this peptide, which may be responsible for the regulation of ischemia induced by extracorporeal shock wave lithotripsy(ESWL), in a rabbit model. Thirty white New Zealand rabbits, each weighing 3–5 kg were used. The animals were divided into three main groups, and varying numbers of shock waves (1,000, 1,500, 2,000) were applied under fluoroscopic localization to the same kidney of all animals. Ketamine HCl anesthesia was administered (15–20 mg/kg) and all of the procedures were performed with a Multimed 2000 lithotriptor. Untreated contralateral kidneys were evaluated as controls. Following HESW application, the treated and untreated kidneys of each animal were removed through bilateral flank incisions under ketamine HCl anesthesia after 24 h and 7 days, respectively. Tissue AM levels were assessed with immunohistochemistry. During the early follow-up period (24 h), both treated and untreated kidneys showed a moderate to high degree of AM positivity. The number of tubules stained with AM increased as the number of shock waves increased and the expression of this protein became evident, possibly due to a higher degree of tissue damage. Additionally, a limited degree of AM positivity was noted in the contralateral kidneys although this was not as evident as the positivity seen in the treated kidneys. Assessment of tissue AM levels during late follow-up (7 days) in both kidneys demonstrated a moderate or limited degree of positivity in the treated kidneys. Limited or no positivity could be demonstrated in the contralateral kidneys at this time.Taking the certain traumatic effects of HESW, which causes transient ischemia during ESWL, into account, we conclude that the application of HESW results in a transient decrease in renal perfusion, causing ischemic injury in treated as well as in contralateral (untreated) kidneys. This ischemic event lasts for a short time and seemed to be dose- and time-dependent. Increased tissue levels of AM appear to be a potential defence against ESWL induced ischemia. [ABSTRACT FROM AUTHOR]

The numerical simulation of the horizontal solidification of pure tin under natural convection and under forced convection induced by Electromagnetic Stirring (EMS) is presented and compared with experimental results obtained by the 'AFRODITE' benchmark setup, described in several previous publications [6–10]. The experiment consists in solidifying a rectangular ingot (100 × 10 × 60 mm) using two lateral heat exchangers which allow the application of a controlled horizontal temperature difference. The experimental temperature difference between the two lateral sides of the sample DT = 40 K and the cooling rate CR = −0.03K/s. Under these conditions the solidification front is planar throughout the experiment. Enthalpy formulation based on fixed-grid techniques is used for the numerical simulations of the phase-change problems, accounting for buoyancy convection and forced convection created by Lorentz forces generated by an external Traveling Magnetic Field (TMF). The temperature distribution obtained by numerical simulation is demonstrated to effectively reproduce the temperature maps obtained from the experimental measurements. The proposed 3D numerical model has demonstrated its effectiveness in predicting the effect of EM stirring on the solidification process in terms of thermal field, dynamic field and the shape and localization of the solidification front. [ABSTRACT FROM AUTHOR]

ST elevation acute myocardial infarction in patients with a mechanical prosthetic valve is rare and usually due to inadequate anticoagulation. We present a case of acute inferior myocardial infarction in a patient with a prosthetic aortic valve and high international normalized ratio, which has not been reported previously. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 56-year-old man who was admitted to the cardiology department because of chest pain. He is examined through echocardiography (ECG) and showed that he has intramyocardial dissecting hematoma with akinesia of apical and anterior wall segments. The author further emphasizes that the disease is found an unusual rupture of the left ventricular wall, septum or right ventricular wall.

A letter to the editor is presented on a case study of a 44-year-old man who underwent pericardiocentesis for the treatment of pericardial tamponade resulting from hemopericardium due to severe thrombocytopenia induced by chemotherapy.

(Echocardiography 2010;27:E115-E116) A 54-year-old man, underwent pericardiocentesis for massive pericardial effusion. Eight hundred milliliters was drained which resulted in improvement of hemodynamic parameters. Ten days later, hemodynamic deterioration occured again. Chest radiograph showed fl uid and air in the pericardium with a nice deliniation border between air and fl uid. It was compatible with pneumopericardium and large pericardial effusion. Transthoracic echocardiography supported the diagnosis with bubbles swirling around heart. Computed tomography confi rmed the diagnosis. We performed pericardiocentesis again. After drainage of 1,050 mL, hemodynamical status of the patient improved. Transthoracic echocardiography and chest radiography controls demonstrated complete disappearance of pericardial fl uid and air (bubbles). [ABSTRACT FROM AUTHOR]

Acute cardiac tamponade is a life-threatening emergency that requires prompt treatment by either percutaneous or surgical pericardiocentesis. It may occur after penetrating or blunt chest trauma. We report a case of pericardial tamponade in the absence of penetrating trauma, due to blast overpressure injury after a dynamite explosion-which has not, to our knowledge, been reported before. Physicians should be aware of the possibility of pericardial tamponade in victims of barotraumatic events such as dynamite or bomb explosions, even in the absence of penetrating trauma. Cardiac tamponade, although life-threatening, is easy to treat when recognized. [ABSTRACT FROM AUTHOR]

Abstract: Cough is a common symptom in cardiovascular disorders and may be defined as an explosive expiration which helps in clearing the tracheobronchial system from secretions and foreign bodies. It is caused by a variety of cardiac and non-cardiac disorders. Although cough is generally accepted as an ominous symptom which indicates progressing or worsening disease state or drug side effect, it might sometimes be a life saving manoeuvre in the catheterization labs. The possible mechanisms by which cough helps us in the catheterization lab are discussed in this letter. [Copyright &y& Elsevier]

Abstract: Double right coronary artery (RCA) is a very rare coronary anomaly. So far, the number of reported cases of double RCA is not so much. Nevertheless, there have been several reports of double RCA in the literature, particularly in the last decade. We aimed to report two cases with double RCA and review the literature in this issue. In brackets, we searched the words – double right coronary artery – in medline (www.ncbi.nlm.nih.gov) and limit the search into the title. According to the results, so far double RCA have been reported 18 times and in 20 cases. Here in this case report and minireview we discussed the characteristics of the previous 20 and the present 2 cases with double RCA. The age of diagnosis of double RCA was in the fifth decade on average. Of the 22 cases reported, 19 were male. 14 of them originated from single ostia whereas 8 from separate ostia. 7 of 22 cases were complicated with atherosclerosis and 4 had associated anomalies. In conclusion, although controversy exists about definition of double RCA and generally considered as a benign entity, it might be atherosclerotic and can cause acute coronary syndromes including myocardial infarction and be associated with other anomalies. It is predominantly seen in males and might origin from either single or separate ostia. Although coronary angiography is the most widely used diagnostic modality, multidetector computed tomography might also be helpful. [Copyright &y& Elsevier]

Introduction: The CHA2DS2-VASc (congestive heart failure, hypertension, age, diabetes mellitus, stroke, vascular disease and sex) score is a simple risk stratification algorithm to estimate stroke/thromboembolic risk in patients with non-valvular atrial fibrillation (AF). Higher pre-stroke CHA2DS2-VASc score is known to be associated with greater stroke severity and poorer outcomes. AF patients generally have higher CHA2DS2-VASc scores than non-AF patients. The Modified Thrombolysis in Cerebral Infarction (mTICI) score is the most widely used grading system to assess the result of recanalizing therapies in acute ischemic stroke (AIS). mTICI 2c and mTICI 3 are conventionally accepted as successful recanalization. Aim: We investigated whether pre-stroke CHA2DS2-VASc score is associated with mTICI recanalization score in AIS patients with and without AF undergoing percutaneous thrombectomy. Material and methods: One hundred fifty-nine patients with the diagnosis of AIS who were admitted within 6 h from symptom onset were included in the study (mean age: 65.7 ±12.9). All subjects underwent endovascular treatment. CHA2DS2-VASc scores of the participants were calculated. Subjects were grouped according to mTICI scores achieved after endovascular treatment. mTICI 2c and mTICI 3 were accepted as successful recanalization. Results: Successful reperfusion was observed in 130 (81.8%) of all patients who underwent endovascular treatment (mTICI flow = 2c) and first-pass reperfusion was observed in 107 (67.3%) patients. When the patients with successful (mTICI flow = 2c) and unsuccessful (mTICI flow = 2b) reperfusion were divided into groups, no significant difference was observed between the patients in terms of comorbidities such as AF, hypertension, hyperlipidemia, coronary artery disease and cerebrovascular accident history. Patients with unsuccessful reperfusion were older than patients with successful reperfusion (71.4 ±11.2 vs. 64.5 ±13.01, p = 0.006), with a higher CHA2DS2-VASc score (4.1 ±1.5 vs. 3.04 ±1.6, p = 0.002). In addition, the duration of the procedure was longer in the unsuccessful reperfusion group (92.4 ±27.2 min vs. 65.0 ±25.1 min, p < 0.001). CHA2DS2-VASc score significantly correlated with successful recanalization (correlation coefficient; 0.243, p = 0.002). Multivariate logistic regression analysis revealed that only CHA2DS2-VASc score (OR = 1.43, 95% CI: 1.09-1.87, p = 0.006) and procedure time (OR = 1.03, 95% CI: 1.01-1.05, p < 0.001) were independent predictors of successful reperfusion. The receiver-operating characteristic (ROC) curve was used to determine the cutoff value for the CHA2DS2-VASc score that best predicts successful reperfusion. The optimal threshold was 3.5, with a sensitivity of 58.6% and specificity of 59.2% (area under the curve (AUC): 0.669, p = 0.005). Conclusions: For the first time in the literature, we investigated and demonstrated that pre-stroke CHA2DS2-VASc score was associated with success of recanalization as assessed with mTICI 2c and mTICI 3 in a cohort of AIS patients regardless of AF presence who underwent endovascular treatment. Our findings deserve to be tested with large scale long term studies. [ABSTRACT FROM AUTHOR]

Exercise-induced ST segment elevation without Q wave formation is rarely observed. Frequent causes are significant coronary stenosis, myocardial bridge and coronary vasospasm. Both exercise-induced ST segment elevation due to slow coronary flow and ST segment elevation in the recovery phase of the exercise stress test are very rare. We present a 49-year-old man with asymptomatic inferolateral ST segment elevation in the recovery phase of the exercise stress test due to slow coronary flow, which has not been reported previously. The learning points of the present paper are as follows: a) although significant coronary stenosis, myocardial bridge and coronary vasospasm are frequent causes of exercise-induced ST segment elevation, slow coronary flow might also cause it; b) one should keep in mind that ST segment elevation might also occur in the recovery phase; and c) ST segment elevation might be asymptomatic, as in the present case. [ABSTRACT FROM AUTHOR]

Introduction: Pituitary abscess is a rare lesion of the pituitary gland that can cause morbidity and mortality in the absence of appropriate treatment. They are classified as primary and secondary pituitary abscesses. Primary pituitary abscesses occur in patients with no previous pituitary pathology. Secondary pituitary abscesses are detected in patients with existing pituitary pathologies. Case presentation: We report a 16-year-old female patient with primary pituitary abscess who was misdiagnosed initially and treated as meningitis. Following the visual disturbances, pituitary abscess was diagnosed, and she underwent abscess drainage via endoscopic endonasal transsphenoidal surgery and antibiotic treatment. Conclusion: Primary pituitary abscess can be clinically confused with other pathologies affecting the central nervous system. In order to avoid permanent sequelae in such patients, it should be kept in mind by physicians in similar cases. Satisfying results are obtained in these patients after appropriate treatment and dramatic improvement is achieved. [ABSTRACT FROM AUTHOR]

Introduction: Dynamic mitral regurgitation (MR) is frequently investigated in patients with left ventricular systolic dysfunction (LVSD). Data about the dynamic MR in patients with organic valve disease are limited. The aim of this study was to evaluate the alteration of MR by exercise in patients with rheumatic valve disease (RVD). Methods: Asymptomatic patients with rheumatic MR and normal left ventricular function had been included in our study. Transthoracic echocardiography and Doppler measurements were performed at rest and just after submaximal exercise test performed with treadmill. Severity of MR was evaluated quantitatively by measuring effective regurgitant orifice area (EROA) with flow convergence method. Results: A total of 34 patients with rheumatic MR had been included. Severity of MR increased in 10 patients with exercise (Group 1) and decreased in 24 of them (Group 2). When the variables of two groups were compared; diastolic blood pressure after exercise, EROA, left atrial volume, left ventricular diastolic volume and mitral annular area values were significantly higher in Group 1 patients. A linear regression model was constructed by considering change of EROA by exercise the dependent, and the variables showing significant differences as the independents. Mitral annular area was found to be independently associated with EROA increase with exercise (R2= 0.499; P < 0.001). Conclusion: Mitral annular dilation is independently associated with increase of MR with submaximal exercise in asymptomatic patients with MR due to RVD with normal left ventricular function. [ABSTRACT FROM AUTHOR]

Background. Patients with severe congestive heart failure (CHF) often have unexplained elevations in serum concentrations of troponin T (TnT), and it is proposed that this is due to cardiac TnT release because of underlying cardiac disease. We investigated whether impaired renal function is an additional underlying phenomenon contributing to increased TnT levels in patients with CHF. Methods. Sixty-two patients with nonischemic CHF, New York Heart Association (NYHA) class III-IV, with normal coronary angiogram and normal serum creatinine were included in the study. Baseline glomerular filtration rate (GFR) was calculated using the Cockcroft Gault equation. Results. Although mean creatinine level was normal (0.92 ± 0.17 mg/dL), mean GFR was low (56 ± 16 mL/min) in the cohort. Elevated (≥0.02 >g/L) TnT was measured in 33 patients (53%). Compared with patients with normal (<0.02 >g/L) TnT levels, patients with elevated TnT had significantly higher NYHA class (p = 0.02), longer duration of disease (p = 0.02), lower GFR (p = 0.0001), and lower LVEF (p = 0.0001). There were significant associations between TnT levels and duration of disease (r = 0.29, p = 0.01), creatinine (r = 0.30, p = 0.01), GFR (r = -0.55, p < 0.0001), and LVEF (r = -0.39, p = 0.001). Independence of these associations was evaluated in multiple linear regression analysis, and serum TnT was independently and negatively associated only with GFR (p = 0.005). Conclusions. Renal function (GFR) correlated significantly and more strongly than cardiac function (LVEF) with the serum TnT levels in patients with CHF. This supports our hypothesis that impaired renal function causes the accumulation of troponin and is very likely the cause of unexplained elevations of serum TnT in patients severe CHF. [ABSTRACT FROM AUTHOR]

Background: Sleep deprivation (SD) is known to be associated with worse cardiovascular outcome including mortality. We investigated the association between acute SD and electrocardiographic maximum QT interval (QTmax), QT, and corrected QT dispersion (QTd/cQTd), which are known to be among predictors of ventricular arrhythmias and sudden death. Methods: We obtained electrocardiograms of 37 healthy young volunteers (age: 28.45 ± 7.97 years; 11 women) after a night with regular sleep and repeated after a night with sleep debt. We measured minimum QT interval (QTmin), QTmax, QTd, and cQTd in milliseconds. Results: Average sleep time of the subjects were 7.7 ± 0.8 hours during regular sleep and 1.7 ± 1.6 hours during a night with sleep debt (P < 0.001). Subjects had similar values of QTmin in milliseconds after a night of sleep debt when compared to after regular sleep (347.56 ± 29.75 vs 344.59 ± 20.89; P = 0.51), whereas they had significantly higher values of QTmax, QTd, and cQTd (396.48 ± 30.11 vs 378.10 ± 23.90; P = 0.001, 49.45 ± 9.11 vs 33.51 ± 10.05; P < 0.001 and 54.92 ± 10.42 vs 37.23 ± 10.81; P < 0.001, respectively). In Pearson's correlation analysis, QTmax, QTd, and cQTd were inversely correlated with sleep time (P = 0.012, r =–0.291; P < 0.001, r =–0.625 and P < 0.001, r =–0.616, respectively) Conclusions: In conclusion, we clearly demonstrated that even one night of SD is associated with significant increase in QTmax, QTd, and cQTd in healthy young adults despite remaining within normal limits. These electrocardiographic changes in acute SD might contribute to development and/or recurrence of arrhythmias. This implication deserves further studies for clarifying the possible linkage between SD and arrhythmias. [ABSTRACT FROM AUTHOR]

The aim of study was to investigate the role of serum total (TPL) and high-density lipoprotein phospholipids (HDL-pl) as a risk factor in coronary heart disease (CHD) and metabolic syndrome (MS). In a random sample, total and HDL-pl were measured in 1088 and 642 adults from Turkey, respectively, who have a high prevalence of MS; this was done with an enzymatic method that measures total phosphatidylcholine, sphingomyelin, and lysophosphatidylcholine. Serum TPL and HDL-pl levels were significantly higher in women (TPL, 2.8 mmol/L; HDL-pI, 1.21 mmoI/L) than in men. Strong correlations existed between serum TPL levels and non-HDL cholesterol (HDL-C), triglycerides, apolipoprotein (apo) B, complement C3, and γ-glutamyltransferase. Non-HDL-C, HDL triglyceride, and apo A-I were strongly correlated with HDL-pl. Linear regression analyses revealed HDL-C, apo B, triglycerides, diabetes, and female gender as independent significant determinants of TPL levels in adults. HDL-C and impaired glucose regulation were sole significant variables, together contributing one-quarter of serum HDL-pl. Individuals with MS or diabetes had significantly higher TPL concentrations. The gender- and age-adjusted odds ratio (OR) of TPL for MS was 1 .73 (95% confidence interval, 1.35-2.21), whereas the multiadjusted OR of HDL-pl per 1 SD increment corresponded to a significantly reduced independent MS likelihood by 26% in women (and 18% in the entire group). The multiadjusted OR of HDL-pl for CHD in men and women combined was 0.32 (P = .057) corresponding to a reduced CHD likelihood by 32% per 1 SD increment of HDL-pl. Plasma TPL levels point to an adverse relationship to MS, whereas their role in CHD risk needs further investigation. HDL-pls, in contrast, mark substantial protection from MS as well as from CHD. [ABSTRACT FROM AUTHOR]

Infective endocarditis (IE) is rarely seen in children, and it can cause significant morbidity and mortality. Congenital heart disease is a predisposing cardiac condition for IE and has an increasing prevalence. A mycotic aortic aneurysm is a rare disease due to infection and it has been reported that it may be a result of IE. We present a 10‐year‐old boy who was referred to our cardiovascular surgery department due to severe aortic stenosis (AS). Transthoracic echocardiography revealed calcific severe AS and computerized tomography (CT) angiography was performed to better evaluate the ascending aorta. CT angiography demonstrated a saccular aneurysm of the ascending aorta. The underlying pathology was considered as chronic IE on top of congenital AS with an unknown number of cusps. Histologic findings supported our diagnosis and accompanied by a saccular aneurysm. The patient underwent a successful aortic root enlargement, mechanical aortic valve replacement, and ascending aorta repair surgery. [ABSTRACT FROM AUTHOR]

Congenital anomalous origin of the coronary arteries is a rare condition with an incidence of 0.6-1.3% in angiographic series. The majority of patients with an anomalous origin of the coronary artery is asymptomatic. They have higher risk of sudden cardiac death if there is external compression of the coronary arteries by the great arteries. There still is not consensus on the management in these patients. In this case report, we present a rare case of a coronary anomaly where both the right coronary artery and the left main coronary artery arise from the right coronary sinus and there is a single ostium. [ABSTRACT FROM AUTHOR]

Introduction: Thymic carcinoma metastases of the spinal column are very rare, especially in pediatric patients. To our knowledge, this is the first such pediatric case in the literature. Case Presentation: We report the case of a 14-year-old male patient with T12 and L1 metastases of thymic carcinoma. He had history of thymectomy and intrathoracic tumor resection 7 months previously. The patient's neurological condition deteriorated; therefore, tumor resection and decompression of the spinal canal were performed. He underwent instrumentation and fusion procedures to prevent spinal instability. Conclusion: The main purpose of the treatment is gross total resection of the thymic carcinoma. However, adjuvant methods such as radiotherapy and chemotherapy should be added to the treatment protocol in patients who have higher stage diseases or those in whom total tumor resection cannot be achieved. [ABSTRACT FROM AUTHOR]

Mechanical prosthetic valve thrombosis is a rare but life threatening complication after valve replacement. Although the traditional treatment of prosthetic valve thrombosis is surgery, recently thrombolytic therapy has been accepted as an alternative treatment. We describe for the first time prosthetic valve obstructive thrombus that was resolved by administering tirofiban (glycoprotein IIb/IIIa receptor antagonist) in a patient using warfarin with an international normalized ratio of 3.4. In our view, although this issue need to be clarified in further studies, tirofiban seems to be an alternative therapy especially in patients who have high risk of bleeding or surgical complication. [ABSTRACT FROM AUTHOR]

A simple testicular cyst is a rare cause of scrotal swelling in infancy. Only 10 cases have been reported in children less than two years of age in the English literature. Pathogenesis of the lesion is unclear. Preoperative diagnosis is possible using ultrasonography (US). Testis-sparing surgery with simple enucleation of the cyst has a favorable outcome. We report two patients with a simple testicular cyst, who were 9 and 8 months of age. The first case was referred with a presumptive diagnosis of hydrocele, and the second infant was admitted with a history of testicular swelling. Ultrasonography provided accurate preoperative diagnosis in both of the cases. The patients were successfully treated with testis-sparing surgery with outstanding long-term results. This unusual lesion of infancy should be considered in the differential diagnosis of a scrotal mass. [ABSTRACT FROM AUTHOR]

Behçet's disease is a multisystem inflammatory disease that manifests with oral-genital ulcers, skin lesions, arthritis, and ophthalmologic and neurovascular findings. Neurological involvement of Behçet's disease is called neuro-Behçet's disease, and it is a difficult entity to diagnose because of insufficient symptoms. We present a 26-year-old male patient with complaints of headache, dizziness, and drop foot in the right lower extremity. He underwent gross total tumor resection with the preliminary diagnosis of low-grade glioma, according to the preoperative magnetic resonance imaging. Histopathological examination and further investigation revealed an interesting neuro-Behçet's disease case because of the localization and clinical occurrence of the lesion. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM) is common in patients with heart failure (HF) and associated with considerable morbidity and mortality. Significant advances have recently occurred in the treatment of T2DM, with evidence of several new glucose-lowering medications showing either neutral or beneficial cardiovascular effects. However, some of these agents have safety characteristics with strong practical implications in HF [i.e. dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1 RA), and sodium-glucose co-transporter type 2 (SGLT-2) inhibitors]. Regarding safety of DPP-4 inhibitors, saxagliptin is not recommended in HF because of a greater risk of HF hospitalisation. There is no compelling evidence of excess HF risk with the other DPP-4 inhibitors. GLP-1 RAs have an overall neutral effect on HF outcomes. However, a signal of harm suggested in two small trials of liraglutide in patients with reduced ejection fraction indicates that their role remains to be defined in established HF. SGLT-2 inhibitors (empagliflozin, canagliflozin and dapagliflozin) have shown a consistent reduction in the risk of HF hospitalisation regardless of baseline cardiovascular risk or history of HF. Accordingly, SGLT-2 inhibitors could be recommended to prevent HF hospitalisation in patients with T2DM and established cardiovascular disease or with multiple risk factors. The recently completed trial with dapagliflozin has shown a significant reduction in cardiovascular mortality and HF events in patients with HF and reduced ejection fraction, with or without T2DM. Several ongoing trials will assess whether the results observed with dapagliflozin could be extended to other SGLT-2 inhibitors in the treatment of HF, with either preserved or reduced ejection fraction, regardless of the presence of T2DM. This position paper aims to summarise relevant clinical trial evidence concerning the role and safety of new glucose-lowering therapies in patients with HF. [ABSTRACT FROM AUTHOR]