Search

Magnolol is a component of the bark of Magnolia officinalis, which is a traditional herbal remedy used in China. In this study, we investigated whether magnolol can reduce myocardial injury induced by renal ischemia and reperfusion (I/R).Renal I/R was elicited by a 60-minute occlusion of the bilateral renal arteries and a 24-hour reperfusion in Sprague-Dawley rats. Magnolol was administered intravenously 10 minutes before renal I/R to evaluate its effects on myocardial injury induced by renal I/R.Renal I/R significantly increased the serum levels of creatine phosphokinase (CPK), lactate dehydrogenase (LDH), and cardiac troponin I and caused myocardial damage. The terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive nuclei and caspase-3 activation was significantly increased in the myocardium, indicating increase of apoptosis. Echocardiography revealed left ventricular dysfunction, as evidenced by reduction of left ventricular ejection fraction and left ventricular fractional shortening. Furthermore, serum levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 were significantly elevated, while the IL-10 level was suppressed. However, intravenously, pretreatment with magnolol at doses of 0.003 and 0.006 mg/kg 10 minutes before renal I/R significantly prevented the increases of CPK, LDH, and cardiac troponin I levels, as well as the histological damage and the apoptosis in the myocardium. Echocardiography showed significant improvement of left ventricular function. Furthermore, the increases in TNF-α, IL-1β, and IL-6 and the decrease in IL-10 were significantly limited, while Bcl-2 was increased and Bax was decreased in the myocardium. Phosphorylation of Akt and extracellular signal-regulated kinases 1 and 2 was increased, while phosphorylation of p38 and c-Jun N-terminal kinase was reduced.Magnolol reduces myocardial injury induced by renal I/R. The underlying mechanisms for this effect might be related to modulation of the production of pro- and anti-inflammatory cytokines and the limiting of apoptosis.

Background The aim of the study was to evaluate the effects of high-dose nitroglycerine administered during cardiopulmonary bypass on the intraoperative cerebral saturation and postoperative serum creatinine concentration in cardiac surgery. Methods In a retrospective cohort study, a total of 239 patients undergoing cardiac surgery with cardiopulmonary bypass at a tertiary medical center were included. General anesthesia consisted of volatile anesthetic and either intravenous loading of high-dose nitroglycerin (infusion rate 10 to 20 mg·h with a total dose of ≥0.5 mg·kg) starting from rewarming of cardiopulmonary bypass throughout the end of the surgery (NTG group; N = 96) or without high-dose nitroglycerin (control group; N = 143). Data for intraoperative cerebral saturation and serum creatinine concentrations before and after cardiac surgery were collected. Propensity score method was used to adjust for potential confounders. Results Patients receiving high-dose nitroglycerin had significantly lower mean arterial pressure and hematocrit levels during and after cardiopulmonary bypass. The risk of intraoperative cerebral desaturation was left-sided 23.9% versus 38.5% (p = 0.023), right-sided 28.1% versus 35.7% in the NTG and control groups, respectively. The risk of new-onset stroke and postoperative dialysis was 2.1% versus 6.3% and 1.0% versus 3.5% in the NTG and control groups, respectively. Conclusion An infusion of high-dose nitroglycerin initiating at rewarming of cardiopulmonary bypass and throughout the postbypass interval may induce hypotension and hemodilution in cardiac surgical patients. Cerebral saturation and renal function were well maintained without increasing the risk of stroke and renal replacement therapy after cardiac surgery with cardiopulmonary bypass.

This study investigated PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) in order to determine the seasonal changes in total benzo[a]pyrene equivalent (BaPeq) concentrations and to identify contamination sources by using a positive matrix factorization model, a conditional probability function, and characteristic ratios of PAHs in Hsinchu. The sampling period was from September 2014 to August 2015. PM2.5 samplers equipped with 47-mm quartz membrane filters were operated at a flow rate of 16.7 L min–1 for 48 h. The concentrations of 20 PAHs were determined through gas chromatography–mass spectrometry. The results revealed the PM2.5, total PAHs, and BaPeq mass concentrations in the four seasons ranged from 4.91 to 58.5 µg m–3, 0.21 to 8.08 ng m–3, and 0.03 to 0.78 ng m–3, respectively. The PM2.5, total PAHs, and BaPeq mass concentrations were in the order winter > autumn > spring > summer and exhibited significant seasonal variations. The carcinogenic potency of PAHs in winter was approximately 6.21 times higher than that in summer. The major BaPeq contributors were BaP, BbF, INP, and DBA. BaP accounted for 49.0% of BaPeq concentrations in PM2.5 in all four seasons. The annual average lifetime excess cancer risk of PM2.5-bound PAHs (1.60 × 10–5) was higher than that specified in the United States Environmental Protection Agency guidelines (10–6). The two major sources were stationary emission sources and unburned petroleum and traffic emissions, which together accounted for 90.3% of PM2.5-bound PAHs.

Baicalein is an active component of Scutellaria baicalensis Georgi, which has traditionally been used to treat cardiovascular diseases in China. In this study, we investigated if treatment with baicalein can attenuate the lung injury induced by myocardial ischemia and reperfusion (I/R). Myocardial I/R, induced by a 40-min occlusion of the left anterior descending coronary artery and a 3-h reperfusion, significantly increased histological damage and the wet-to-dry weight ratio of lungs in rats. The terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive nuclei and caspase-3 activation was significantly increased in the lungs. Serum and bronchoalveolar lavage fluid levels of tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]), interleukin-1[Formula: see text] (IL-1[Formula: see text]), and interleukin-6 (IL-6) were significantly elevated, as were TNF-[Formula: see text] levels in the lung. Intravenous administration with baicalein at doses of 3, 10, and 30[Formula: see text]mg/kg for ten minutes before myocardial I/R significantly reduced histological damage, the wet-to-dry weight ratio, and apoptosis in the lung. Baicalein also significantly inhibited the increase in levels of TNF-[Formula: see text], IL-1[Formula: see text], and IL-6. Moreover, baicalein increased Bcl-2 and decreased p53, Bax, and cytochrome [Formula: see text] in lungs. Phosphorylation of the prosurvival kinases, including Akt and extracellular signal-regulated kinases 1 and 2 (ERK1/2), was increased, while the phosphorylation of the pro-apoptotic mitogen-activated protein kinases, including p38 and c-Jun N-terminal kinase (JNK), was decreased. In conclusion, treatment with baicalein attenuates the lung injury induced by myocardial I/R. The mechanisms might be related to the limiting of apoptosis, possibly via the inhibition of both the extrinsic and intrinsic pathways of apoptosis, including the inhibition of TNF-[Formula: see text] production and modulation of pro- and anti-apoptotic signaling elements.

Objective We aimed to determine whether high-dose nitroglycerin, a nitric oxide donor, preserves erythrocyte deformability during cardiopulmonary bypass and examines the signaling pathway of nitric oxide in erythrocytes. Methods In a randomized and controlled fashion, forty-two patients undergoing cardiac surgery with hypothermic cardiopulmonary bypass were allocated to high-dose (N = 21) and low-dose groups (N = 21). During rewarming period, patients were given intravenous nitroglycerin with an infusion rate 5 and 1 µg·kg-1 ·min-1 in high-dose and low-dose groups, respectively. Tyrosine phosphorylation level of non-muscle myosin IIA in erythrocyte membrane was used as an index of erythrocyte deformability and analyzed using immunoblotting. Results Tyrosine phosphorylation of non-muscle myosin IIA was significantly enhanced after bypass in high-dose group (3.729 ± 1.700 folds, P = .011) but not low-dose group (1.545 ± 0.595 folds, P = .076). Phosphorylation of aquaporin 1, vasodilator-stimulated phosphoprotein, and focal adhesion kinase in erythrocyte membrane was also upregulated in high-dose group after bypass. Besides, plasma nitric oxide level was highly correlated with fold change of non-muscle myosin IIA phosphorylation (Pearson's correlation coefficient .871). Conclusions High-dose nitroglycerin administered during cardiopulmonary bypass improves erythrocyte deformability through activating phosphorylation of aquaporin 1, vasodilator-stimulated phosphoprotein, and focal adhesion kinase in erythrocytes.

Baicalein is a component of the root of Scutellaria baicalensis Georgi, which has traditionally been used to treat liver disease in China. In the present study, we investigated baicalein’ ability to reduce the liver injury induced by myocardial ischemia and reperfusion (I/R). Myocardial I/R was induced in this experiment by a 40[Formula: see text]min occlusion of the left anterior descending coronary artery and a 3[Formula: see text]h reperfusion in rats. The induced myocardial I/R significantly increased the serum levels of aspartate transaminase (AST) and alanine transaminase (ALT), indicating the presence of liver injury. Hepatic apoptosis was significantly increased. The serum levels of tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]), interleukin-1[Formula: see text] (IL-1[Formula: see text]), and interleukin-6 (IL-6) were significantly elevated, as was the TNF-[Formula: see text] level in the liver. Intravenous pretreatment with baicalein (3, 10, or 30[Formula: see text]mg/kg) 10[Formula: see text]min before myocardial I/R significantly reduced the serum level increase of AST and ALT, apoptosis in the liver, and the elevation of TNF-[Formula: see text], IL-1[Formula: see text], and IL-6 levels. Moreover, baicalein increased Bcl-2 and decreased Bax in the liver. Phosphorylation of the prosurvival kinases, including Akt and extracellular signal-regulated kinases 1 and 2 (ERK1/2), was also increased. In conclusion, we found that baicalein can reduce the liver injury induced by myocardial I/R. The underlying mechanisms are likely related to the inhibition of the extrinsic and intrinsic apoptotic pathways, possibly via the inhibition of TNF-[Formula: see text] production, the modulation of Bcl-2 and Bax, and the activation of Akt and ERK1/2. Our findings may provide a rationale for the application of baicalein or traditional Chinese medicine containing large amounts of baicalein to prevent liver injury in acute myocardial infarction and cardiac surgery.

Acute kidney injury is a common and severe complication of acute myocardial infarction and cardiac surgery. It results in increased mortality, morbidity, and duration of hospitalization. Baicalein is a component of the root of Scutellaria baicalensis, which has traditionally been used to treat cardiovascular and liver diseases in Asia. In this study, we investigated whether baicalein can attenuate kidney injury induced by myocardial ischemia and reperfusion in rats. Myocardial ischemia and reperfusion, induced by a 40-minute occlusion and a 3-hour reperfusion of the left anterior descending coronary artery, significantly increased blood urea nitrogen and creatinine levels in addition to causing histological changes in the kidneys. Kidney apoptosis was also significantly increased. Furthermore, myocardial ischemia and reperfusion significantly increased the serum levels of tumor necrosis factor-α, interleukin-1, and interleukin-6 as well as the tumor necrosis factor-α levels in the kidneys. Intravenous pretreatment with baicalein (in doses of 3, 10, or 30 mg/kg), however, significantly reduced the increases in the creatinine level, renal histological damage, and apoptosis induced by myocardial ischemia and reperfusion. In addition, the increases in the serum levels of tumor necrosis factor-α, interleukin-1, and interleukin-6, and of tumor necrosis factor-α in the kidneys were significantly reduced. Western blot analysis revealed that baicalein significantly increased Bcl-2 and reduced Bax in the kidneys. The phosphorylation of Akt and extracellular signal-regulated kinases 1 and 2 was also significantly increased. In conclusion, baicalein significantly attenuates kidney injury induced by myocardial ischemia and reperfusion. The underlying mechanisms might be related to the inhibition of apoptosis, possibly through the reduction of tumor necrosis factor-α production, the modulation of Bcl-2 and Bax, and the activation of Akt and extracellular signal-regulated kinases 1 and 2.

Background: We have previously reported that brief pressure overload of the left ventricle reduced myocardial infarct (MI) size. However, the role of protein kinase C (PKC) remains uncertain. In this study, we investigated whether pressure overload reduces MI size by activating PKC. Methods: MI was induced by a 40-minute occlusion of the left anterior descending coronary artery and a 3-hour reperfusion in anesthetized Sprague-Dawley rats. MI size was determined using triphenyl tetrazolium chloride staining. Brief pressure overload was achieved by two 10-minute partial snarings of the ascending aorta, raising the systolic left ventricular pressure 50% above the baseline value. Ischemic preconditioning was elicited by two 10-minute coronary artery occlusions and 10-minute reperfusions. Dimethyl sulfoxide (vehicle) or calphostin C (0.1 mg/kg, a specific inhibitor of PKC) was administered intravenously as pretreatment. Results: The MI size, expressed as the percentage of the area at risk, was significantly reduced in the pressure overload group and the ischemic preconditioning group (19.0 ± 2.9% and 18.7 ± 3.0% vs. 26.1 ± 2.6% in the control group, where p

Both apoptosis and necrosis contribute to cell death after myocardial ischemia and reperfusion. We previously reported that brief left ventricular pressure overload (LVPO) decreased myocardial infarct (MI) size. In this study, we investigated whether brief pressure overload reduces apoptosis and the mechanisms involved.MI was induced by a 40-min occlusion of the left anterior descending coronary artery and 3-h reperfusion in male anesthetized Sprague-Dawley rats. Brief LVPO was achieved by two 10-min partial snarings of the ascending aorta, raising the systolic left ventricular pressure 50% above the baseline value. Ischemic preconditioning was elicited by two 10-min coronary artery occlusions and 10-min reperfusions.Brief LVPO and ischemic preconditioning significantly decreased MI size (P0.001). Brief pressure overload significantly reduced myocardial apoptosis, as evidenced by the decrease in the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive nuclei (P0.001), little or no DNA laddering, and reduced caspase-3 activation (P0.01). Moreover, brief pressure overload significantly increased Bcl-2 (P0.001) and decreased Bax (P0.001) and p53 (P0.01). Akt phosphorylation was significantly increased by brief pressure overload (P0.001), whereas c-Jun N-terminal kinase phosphorylation was significantly decreased (P0.001). Hemodynamics, area at risk, and mortality did not differ significantly among groups.Brief left LVPO significantly reduces myocardial apoptosis. The underlying mechanisms might be related to modulation of Bcl-2 and Bax, inhibition of p53, increased Akt phosphorylation, and suppressed c-Jun N-terminal kinase phosphorylation.

Magnolol, a constituent of the bark of Magnolia officinalis, has been reported to decrease myocardial stunning and infarct size. In this study, we investigated whether magnolol can reduce renal ischemia and reperfusion (I/R) injury. Renal I/R, induced by a 60-min occlusion of bilateral renal arteries and a 24-h reperfusion, significantly increased blood urea nitrogen (BUN) and creatinine levels, and caused histological damage to the kidneys of rats. Apoptosis, as evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining and caspase-3 activation, was significantly increased in the kidneys. Furthermore, serum levels of tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were significantly elevated, while the interleukin-10 (IL-10) level was suppressed. However, intravenous pretreatment with magnolol at doses of 0.003[Formula: see text]mg/kg and 0.006[Formula: see text]mg/kg 10[Formula: see text]min before renal I/R significantly limited the increases of BUN, creatinine, the histological damage, and apoptosis in the kidneys. The increases in TNF-[Formula: see text], IL-1β, and IL-6, and the decrease in IL-10 were also significantly inhibited. Additionally, magnolol increased Bcl-2 and decreased Bax in the kidneys. Phosphorylation of the prosurvival kinases, including Akt and extracellular signal-regulated kinases 1 and 2 (ERK1/2), was elevated, while phosphorylation of the pro-apoptotic mitogen-activated protein kinases, including p38 and c-Jun N-terminal kinase (JNK), was suppressed. In conclusion, magnolol reduces renal I/R injury. The underlying mechanisms for this effect might be related to the prevention of apoptosis, possibly via the inhibition of both extrinsic and intrinsic apoptotic pathways, including the reduction of TNF-[Formula: see text] production and the modulation of pro- and anti-apoptotic signaling elements.

OBJECTIVES Acute kidney injury is a common and serious complication of cardiac surgery. Because its underlying mechanisms are unclear, there is no specific therapy to prevent or treat it. A regional transient ischaemia and reperfusion (I/R) may provide protection to distant tissue or organs, a phenomenon known as remote preconditioning. In this study, we investigated whether myocardial preconditioning (MPC) would reduce kidney injury and apoptosis induced by myocardial I/R, as well as the mechanisms involved. METHODS Myocardial I/R was induced by a 40-min occlusion of the left anterior descending artery and a 3-h reperfusion in anaesthetized Sprague-Dawley rats. MPC was elicited by two 10-min coronary artery occlusions and two 10-min reperfusions. A sham group received the same surgical procedures without coronary artery occlusion and reperfusion. RESULTS Compared with the sham group, myocardial I/R significantly increased the serum creatinine levels (1.15 ± 0.44 vs 0.54 ± 0.23 mg/dl, P < 0.05, mean ± standard deviation) and renal histological damage, indicating increased kidney injury. Kidney apoptosis was also significantly increased, as evidenced by the increase in the terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate (dUTP) nick-end labelling (TUNEL)-positive nuclei, clear DNA laddering and increased caspase-3 activation. Serum levels of tumour necrosis factor-α (TNF-α), interleukin-1 (IL-1) and interleukin-6 (IL-6) were significantly elevated, as were TNF-α levels in the kidneys. MPC significantly decreased myocardial infarct size (18.5 ± 3.1 vs 25.6 ± 2.1% of area at risk, P < 0.001). Additionally, MPC significantly reduced the serum creatinine level (0.65 ± 0.19 mg/dl, P < 0.05), renal histological damage and apoptosis. The increase in the serum levels of TNF-α, IL-1 and IL-6, and of TNF-α in the kidneys, was significantly inhibited. Western blot analysis found that MPC significantly increased Bcl-2 and decreased Bax in the kidneys. Phosphorylation of Akt and extracellular signal-regulated kinases 1 and 2 (ERK1/2) was significantly increased. Haemodynamics, area at risk and mortality did not differ significantly among the groups. CONCLUSIONS MPC significantly reduces kidney injury and apoptosis induced by myocardial I/R. The underlying mechanisms might be related to inhibition of both the extrinsic and intrinsic pathways of apoptosis, possibly via inhibition of TNF-α production, modulation of Bcl-2 and Bax and activation of Akt and ERK1/2.

Background: We previously reported that pressure overload of the left ventricle reduced myocardial infarct (MI) size in rabbits. The threshold of pressure overload was investigated in this study. Methods: Pressure overload of the left ventricle was induced by partial snare of the ascending aorta in anesthetized, open-chest rabbits. Systolic left ventricular pressure (SLVP) was elevated 50% or 30% above baseline value by varying the degree of partial snaring. Different duration of pressure overload, including 10 minutes, 5 minutes, 3 minutes, or 2 minutes, was applied to determine the threshold of protective effects. Ischemic preconditioning was elicited by two 10-minute coronary artery occlusions and reperfusions. Ten minutes after different pretreatment, 1 hour occlusion of the left anterior descending coronary artery followed by 3 hours reperfusion was done to induce MI. The size of area at risk and MI were determined by blue dye injection and triphenyl tetrazolium chloride staining after experiments. Results: Pressure overload increase of SLVP 50% above baseline value for 10 minutes, 5 minutes, and 3 minutes significantly reduced MI size (18.5 ± 3.6%, 21.4 ± 1.9% and 21.6 ± 1.7%, respectively, vs. 26.6 ± 1.0% in the control group, mean ± standard deviation, p

Usually, humanoid walking gaits are only roughly distinguished between stable and unstable. The evaluation of a stable humanoid walking gait is difficult to quantify in scales. And, it is extremely hard to adjust humanoid robots in suitable a walking gait for different movement objectives such as fast walking, uneven floor walking, and so on. This paper proposes a stability margin constructed by center of pressure (COP) to evaluate the gait stability of humanoid walking. The stability margin is modeled by the COP regions that a humanoid robot needs for stable standing. We derive the mathematical model for COP position by dividing the walking gait into single and double support phases in order to measure the stability of the COP regions. An actual measuring system for the stable COP regions is designed and implemented. The measured COP trajectory of a walking gait is eventually evaluated with respect to the stable COP regions for the stability margins. The evaluation focuses on weak stability areas to be improved for robust walking gaits. To demonstrate the robustness of the improved walking gait, we replicate the experiment on three different terrains. The experiments demonstrate that the walking gaits developed based on stable COP region can be applied for different movement objectives.

A previously found analytical expression for the fully developed concentration profile of aerosol particles flowing through a circular tube under laminar conditions has been used to derived a simple analytical expression to determine particle penetration. The resulting expression, P= 0.846 exp (-3.659 ß) where ß is the dimensionless diffusion coefficient of the particle, has been compared satisfactorily with the well-known Gormley-Kennedy equation even for values of ß as low as 0.04 in spite that, in principle, the approximate expression for the fully developed concentration profile is only valid for ß>0.2. 2016 Elsevier Ltd. All rights reserved., This work was partly supported by Spain׳s Minesterio de Economia y Competitividad under Grant MINECOR13/P73.

Background Less invasive cardiac surgery is widely adopted nowadays. Upper or lower partial sternotomy is an approach for less invasive cardiac surgery. We report results of less invasive cardiac surgery via partial sternotomy. Methods From August 1, 2009 to September 30, 2010, 35 patients underwent cardiac surgery via upper or lower partial sternotomy. The preoperative characteristics, operative variables, mortality, and morbidity were reviewed retrospectively. Results Thirty-five patients underwent cardiac surgery via partial sternotomy during the study period. Eleven patients (31%) were female. The mean age was 66 ± 11 years (range 38 to 88). Seven patients underwent aortic valve replacement via upper partial sternotomy. Simultaneous mitral valve replacement was done in one patient. Lower partial sternotomy was done in 28 patients. Sixteen patients received mitral valve replacement. Three patients underwent mitral valve repair. Concomitant tricuspid valve repair was done in eight patients. Two patients received aortic valve replacement. One patient had replacement of aortic and mitral valve replacement. One patient had repair of tricuspid valve. Two patients received LIMA anastomosis to the LAD. Two patients underwent emergent repair of the right ventricle. One patient had resection of myxoma in the left atrium. Direct cannulation of the aorta and right atrium was used for cardiopulmonary bypass in 15 patients (48%). Both antegrade and retrograde administration of cardioplegia solution was used routinely for myocardial protection. There was no mortality. Two patients developed respiratory failure. One patient suffered unstable sternum. One patient required conversion to full sternotomy. No patient suffered mediastinitis or groin wound infection. Conclusion Upper or lower partial sternotomy provides adequate exposure for various kind of cardiac surgery. Conventional cardiopulmonary bypass and cardioplegia solution administration can be used. The immediate preliminary outcome was acceptable.

The ambient PAHs levels in the downtown area of a traditional small city were analyzed for winter and summer seasons. A total of 16 PAHs in gaseous and particulate phase were quantified. The average gaseous PAHs were 2,189 ± 1,194 and 623.8 ± 545.1 ng/m(3) in winter and summer seasons, respectively. For the PAHs in particulate phase, they were 40.32 ± 12.15 and 11.99 ± 5.63 ng/m(3) in winter and summer seasons, respectively. These values were comparable to those reported for large cities or even higher. The estimated BaPeq was 12.32 ± 6.34 ng/m(3). As low-molecular-weight PAHs primarily existed in gaseous phase, high-molecular-weight PAHs in particulate phase became a significant fraction of total particulate phase PAHs. Particulate phase PAHs was significantly inversely associated with the ambient temperature for each individual PAHs species. However, this relationship did not exist for high-molecular-weight PAHs in gaseous phase. The results indicated the photo-degradation of high-molecular-weight PAHs should warrant a further thoughtfully investigation.

We previously reported brief pressure overload of the left ventricle reduced myocardial infarct size. The role of adenosine receptors was investigated in this study.Pressure overload was achieved by two 10-minute partial snaring of the ascending aorta. Systolic left ventricular pressure was raised 50% above baseline value. Ischemic preconditioning was elicited by two 10-minute coronary artery occlusions. Ten minutes after different pretreatments, 60-minute occlusion of the left anterior descending coronary artery followed by 3-hour reperfusion was done to induce infarction. The area at risk and myocardial infarct size were determined by Evans blue dye injection and triphenyltetrazolium chloride staining.Myocardial infarct size (mean ± standard deviation), expressed as percentage of area at risk, was significantly reduced in the pressure overload group (19.3 ± 2.5 %, p0.001) and in the ischemic preconditioning group (18.3 ± 1.8 %, p0.001) versus the control group (27.3 ± 3.3 %). Pretreatment with 8-(p-sulfophenyl)-theophylline, an adenosine receptor antagonist, limited the protection by ischemic preconditioning (26.8 ± 3.7%), but not that by pressure overload (19.2 ± 2.5%, p0.001). The 8-(p-sulfophenyl)-theophylline did not significantly affect the extent of infarct (26.4 ± 5.4%). The hemodynamics prior to treatment, area at risk, and mortality were not significantly different among all groups of animals.Brief pressure overload of the left ventricle preconditioned rabbit myocardium against infarction. Because 8-(p-sulfophenyl)-theophylline had no significant effect on this response, the results are consistent with the hypothesis that the underlying mechanism does not depend on activation of adenosine receptors.

In this study, nanoparticle (NP, diameter 100 nm during bagging or feeding processes, unless there were combustion-related incidental sources existed. Large fraction of nanomaterials was found in the RPM due to agglomeration of nanomaterials or attachment of nanomaterials to the larger particles. From this study, it is concluded that RPM concentration measurements are necessary for the exposure assessment of nanoparticles in workplaces.

Background Obesity has numerous adverse effects on general, and especially, cardiovascular health. Plasma adiponectin, an adipokine, is inversely related to adipose tissue mass, and also the prognosis of heart failure and coronary artery disease (CAD). Coronary artery bypass grafting (CABG) surgery is usually the treatment of choice for patients with complex CAD. Objective To investigate the impact of body mass index (BMI) and the associated biomarkers on clinical outcomes after CABG. Methods Patients with CAD who underwent CABG by a single cardiac surgeon team were prospectively enrolled and followed for up to 5 years after CABG. Results Among the 234 consecutive patients (aged 70.4±10.5 years, BMI 24.68±3.27 kg/m 2 , 84.6% men), there were 76 mortalities during follow-up. BMI was negatively correlated with adiponectin (r=−0.203, p=0.003), high-sensitivity C-reactive protein (hsCRP; r=−0.176, p=0.009), and N-terminal pro-brain natriuretic peptide (NT-proBNP; r=−0.271, p 2 ) had a decreased event free survival when compared with overweight or obese patients (BMI ≥25 kg/m 2 ). After accounting for age, sex, manifest acute coronary syndrome, glomerular filtration rate, and left ventricular ejection fraction, BMI remained correlated with cardiovascular mortality in the study population. (HR and 95% CI per 1 kg/m 2 : 0.912 (0.833 to 0.998)). However, adiponectin, hsCRP, and NT-proBNP would abolish the prognostic impact of BMI. In addition, risk-stratified subgroup analysis showed that adiponectin, hsCRP and NT-proBNP predicted mortality in patients with normal weight, rather than in overweight or obese patients. Conclusions BMI was inversely associated with the prognosis of CABG. Such association may be linked to the baseline mechanisms related to metabolic disorder (adiponectin) and systemic inflammation (hsCRP). Future pathophysiological validation is indicated.

A numerical investigation has been carried out to examine the electrostatic loss of nanoparticles in a corona needle charger. Two-dimensional flow field, electric field, particle charge, and particle trajectory were simulated to obtain the electrostatic deposition loss at different conditions. Simulation of particle trajectories shows that the number of charges per particle during the charging process depends on the particle diameter, radial position from the symmetry axis, applied voltage, Reynolds number, and axial distance along the charger. The numerical results of nanoparticle electrostatic loss agreed fairly well with available experimental data. The results reveal that the electrostatic loss of nanoparticles increases with increasing applied voltage and electrical mobility of particles; and with decreasing particle diameter and Reynolds number. A regression equation closely fitted the obtained numerical results for different conditions. The equation is useful for directly calculating the electrostatic loss of nanoparticles in the corona needle charger during particle-charging process.

An analyticalapproximationispresentedforthedimensionlessconcentrationprofile n(r,x) ofaerosolparticlesofdiffusioncoefficient D flowingwithmeanaxialvelocity u in a cylindricaltubeoflength L and radius R, nðr; xÞ ¼ nmaxðxÞf ðrÞ ¼ C expð lbxÞ 1 1 11 ð18r2 9r4þ2r6Þ wherein C=1.477and l=3.659arefitconstantstothenumericalsolutionofthe convection–diffusionequationfor bx ¼ DLx=uR2Z0:2, i.e.forfullydevelopedconcen- tration profile, This workwaspartlysupportedbytheSpanishMinisteriodeCienciaeInnovacio´n underGrantDPI2008-06199.Weare grateful toProf.GerhardKasperforhisadvicesandsuggestionsinthepreparationofthefinalformofthispaper.

This study evaluated the relationship between the real-time concentration measurements of inhalable particles whose diameters were less than 10 microm, from a light scattering monitor and a beta gauge monitor, at various instantaneous relative humidities. This work demonstrated that the mean inhalable particle concentrations as measured by the light scattering monitor were higher than those of the manual sampler, such that a factor of 0.74 was employed to adjust the light scattering monitor for inhalable particle concentration measurements. The mean inhalable particle concentrations determined by the beta gauge monitor at a low relative humidity setpoint correlated well with those obtained by the manual sampler. The real-time inhalable particle concentration of the adjusted light scattering monitor was further compared to those of the beta gauge monitor to investigate the effect of instantaneous relative humidity on the mass readings of the automatic monitors. The results demonstrated that the estimated concentration measurements by the adjusted light scattering monitor should be re-calibrated in real-time to improve the accuracy of the inhalable particle concentrations at various instantaneous relative humidities.

This study elucidates the feasibility of using a packed dielectric barrier discharge approach to remove particulate matter from an air stream. The experimental results reveal that the particle removal efficiency of the packed dielectric barrier discharge system rose to 92.2% for 0.3 μm particles as the discharge voltage was increased to 20 kV at an operating frequency of 60 Hz. Only when the discharge voltage was sufficiently high to remove particulate matter did the particle removal efficiency increase with the operating frequency. The power required to adjust the discharge voltage was less than that required to adjust the operating frequency at the particular removal efficiency. Accordingly, energy can be saved in a packed dielectric barrier discharge system by adjusting the discharge voltage rather than the operating frequency to remove particulate matter from the air stream.

This study examined how relative humidity affects the hourly PM2.5 readings of two collocated beta attenuation monitors in the field. Relationships between PM2.5 readings by a stationary beta gauge A and a portable beta gauge B were evaluated at various relative humidity (RH) setpoints and ambient RHs. The PM2.5 concentrations of two beta attenuation monitors were also compared with those of a collocated manual sampler. This work demonstrated that the mean PM2.5 concentrations by the beta gauge monitors with RHA and RHB (RH setpoint in beta gauge A and B) of 35% result in good agreement with those by the manual sampler. The PM2.5 readings of RHB of 35% correlated well with those 35% of RHA , whenever the inlet air of beta gauge B was conditioned with water vapor or the beta gauge was operated normally under ambient conditions. However, the PM2.5 readings of the beta gauge obtained at RH B=65% exceeded those obtained at RHA=35%. The mean PM2.5 readings for RH B65% to RHA = 35% were 1.91 and 1.26, with (amb...

This study utilized the activated carbon fiber (ACF) modified with metal catalyst via physical vapor deposition (PVD) process (ACF/PVD) to diminish ozone. Furthermore, the ozone removal efficiency of ACF/PVD was compared with that of original ACF and ACF modified with metal catalyst via impregnation process (ACF/impregnation). In addition to the kinds of coated metal and the inlet ozone concentrations, the effects of the coating thickness and the reaction temperature on ACF/PVD for ozone removal were also examined. The results indicate that the ozone removal efficiency of ACF/PVD is better than that of original ACF and ACF/impregnation. The ozone removal efficiency of different metal-coated ACF/PVD in the superior order is gold (Au), and manganese (Mn). The increase of Au-coated thickness (3 nm to 80 nm) on ACF/PVD will enhance the ozone removal. However, when the Mn-coated thickness on ACF/PVD is larger than 15 nm, the ozone removal efficiency displays a declining trend. Furthermore, a higher reaction temperature will result in a better ozone removal of ACF/PVD and the original ACF.

This investigation experimentally explores the penetration curve of particles shot onto a stainless steel fibrous filter or a flat surface. The effect of the pore size of the stainless steel fibrous filter, with or without an oil coating, on the particle penetration was examined at various flow rates, nozzle diameters and dimensionless particle diameters, Sqrt(Stk). The penetration of the flat surface by particles was also determined for comparison. Experimental results demonstrate that oleic acid particles larger than Sqrt(Stk)50 are collected on the stainless steel fibrous filter with a low penetration, while smaller particles stay in the particle-laden stream with high penetration. The penetration of potassium chloride particles exceeds that of oleic acid particles, because potassium chloride particles bounce off the stainless steel fibrous filter and the flat surface. Particles bounce off the metal filter less easily than the flat surface. Coating the stainless steel fibrous filter with oil effectively reduces problems of particle bounce. The potassium chloride particles sucked the coated oil forming a small mountain on the surface. When the loaded particle mass on the coated stainless steel fibrous filter ranges between 0.4 and 2.3 mg, Sqrt(Stk)50 is a constant 0.35.

An efficient venturi scrubber system combining a particle growth device and a traditional venturi scrubber was designed and tested in the laboratory. Before the venturi scrubber, saturated steam at 100°C was mixed with normal temperature waste stream to achieve supersaturation conditions allowing submicron particles to grow into micron sizes. Hence the control efficiency of submicron particles was greatly enhanced at a reasonably low pressure drop as compared to that found in the literature. At a flow rate of 250 L∕min and a liquid to gas ratio of 2.5 L∕ m3 , the control efficiency of the present venturi scrubber system for NaCl particles greater than 100 nm is greater than 90%, and pressure drop is only about 44 cm H2 O (4.3 kPa) . In comparison, to remove only 50% of 0.6 μm particles at the same liquid to gas ratio, the pressure drop needed will be greater than 200 cm H2 O (or 19.6 kPa ). Theoretical calculation has also been conducted to simulate particle growth process and the control efficiency of th...

This investigation experimentally studied the penetration curve of particles that impact on a sintered stainless‐steel filter with various pore sizes, sampling flow rates and jet diameters. The penetration curves were compared to those with an aluminum foil substrate. Test data reveal that when the sintered stainless‐steel filter has larger pore sizes (100 µm or 40 µm), the particle penetration, P(%), is lower and the curve is less steep than that obtained from the aluminum foil substrate. The penetration curve of the sintered stainless‐steel filter with smaller pore size (5 µm) is close to that of the aluminum foil substrate. The dimensionless cutsize‐shift (the ratio of the dimensionless cutsize of sintered stainless‐steel filter to that of aluminum foil) falls as the pore sizes and the Reynolds number increase. Experimental data were then compared with theoretical results, and theory over‐predicted the dimensionless cutsize‐shift. Hence, a regression equation for the dimensionless cutsize‐shif...

In this study, PM2.5 mass readings by a portable light scattering monitor (Dust Trak) were compared to those obtained using a collocated beta gauge monitor (E-BAM) at various ambient relative humidities. The mass readings of two automatic particle monitors were also compared with those of a manual sampler. The inlet heater of the beta gauge was actuated or switched off to determine whether ambient relative humidity has an effect on the beta gauge readings. This work demonstrated that PM2.5 readings of the light scattering monitor were higher than those of the beta gauge monitor, regardless of whether the inlet heater was turned on or off. In addition, the mean PM2.5 readings of the light scattering monitor were also higher than those of the manual sampler. Results indicated that the relative humidity affected PM2.5 reading of the light scattering monitor and PM2.5 reading increased as the relative humidity rose. In contrast, when the inlet heater of the beta gauge was switched on, the mean PM2.5 mass reading of beta gauge monitor was close to that of the manual sampler, and it was lower than that of the light scattering monitor. The inlet heater appeared to avoid the relative humidity effect on PM2.5 mass readings of the beta gauge monitor.

© 2015, Springer Science+Business Media Dordrecht. An electrical charger, based on a point-to-plate DC corona discharge, for the high-efficiency charging of aerosol particles with diameter of a few nanometers, has been designed, constructed, and evaluated. The discharge takes place between a needle and a perforated plate, and the results presented here have shown that this specific design allows reduction of electrostatic losses of charged particles within the charger in comparison with other typical designs. Besides, the small effective volume of the charger leads to a relatively small diffusion loss of particles. As a consequence of the reduced electrostatic and diffusion losses, the extrinsic charging efficiency attainable is higher than in similar devices., This work was partly supported by Spain’s Ministerio de Economía y Competitividad under Grant MINECOR13/P73.

We tested the hypothesis that cardiac nerves may mediate ischemic preconditioning. Pigs were chronically instrumented to measure aortic, left atrial and left ventricular pressures, and regional myocardial function (wall thickening). Hemodynamic variables, area at risk, and tissue blood flows (radioactive microspheres) were similar among groups. Myocardial infarct size following 60 minutes coronary artery occlusion and 4 days reperfusion, expressed as a fraction of the area at risk, was 42±4.0%, in innervated pigs and similar in pigs with regional cardiac denervation (CD, 41±2.5%). Infarct size in innervated pigs during the first window of preconditioning (first window) was markedly reduced (6±1.8%, P P P 1 -adrenergic receptor (AR) blockade, infarct size was also not reduced during the second window (48±3.2%). Additionally, Western blot analysis of inducible nitric oxide synthase and cyclooxygenase-2 proteins demonstrated significant ( P 1 -AR blockade. Thus, the mechanism of protection during the second window, but not the first window, appears to be dependent on cardiac nerves and α 1 -AR stimulation.

BackgroundCoronary artery bypass grafting surgery (CABG) remains a challenge for patients with coronary artery disease and left ventricular (LV) dysfunction. The aim of this study was to evaluate the result of CABG in patients with LV dysfunction.MethodsMedical records of 1,847 patients who underwent primary, isolated CABG at Taipei Veterans General Hospital from January 1, 1991 to December 31, 2002, were reviewed. The mortality rate associated with clinical and operative variables was compared between patients with LV ejection fraction (LVEF) = 35% and patients with LVEF < 35%.ResultsPatients with LVEF < 35% had more episodes of myocardial infarction (57.5% vs 28.9%, p < 0.001) and history of congestive heart failure (18.1% vs 3.2%, p < 0.001), higher New York Heart Association (NYHA) class, and higher angina class. Longer cardiopulmonary bypass time (147 ± 44 minutes vs 137 ± 40 minutes, p < 0 .001) but fewer left internal mammary artery (LIMA) grafts (46.8% vs 65.7%, p < 0.001) were used in patients with LVEF < 35%. Patients with LVEF < 35% had significantly higher hospital mortality (6.6% vs 2.2%, p < 0.001), higher major morbidity (23.3% vs 16.1%, p < 0.01), and longer hospital stay (25 ± 23 days vs 21 ± 16 days, p < 0.01).ConclusionAlthough patients with LV dysfunction had higher mortality and morbidity, CABG could be done in these high-risk patients with acceptable results.

Wind tunnel experiments were conducted to measure the emission factor of particle reentrainment from a dust sample with or without a porous fence. The effect of wind velocity, fence porosity, and distance between the fence and the dust sample on the emission factor was studied. A 20% porous fence was found to be effective for reducing the particle reentrainment at a low wind velocity of 5 m∕s . When the wind velocity was increase from 7 to 15 m∕s , the results show that the particle reentrainment can also be reduced in a certain region behind the fence ( x∕H

This investigation numerically examined the cutoff aerodynamic diameter (da50) and the sharpness (GSD) of the particle collection efficiency curve of impactors with a finite impaction plate diameter. Results revealed that the inertial impactors have a limited cutoff aerodynamic diameter at different air velocities. The extreme value of the cutoff aerodynamic diameter increases with the nozzle diameter (W)/the plate diameter (Dc). The computed da50/Dc values of the impactors increase with W/Dc at various Reynolds numbers (Re) and with the nozzle-toplate distance (S)/Dc when Re is 100. The value of GSD slightly increases with W/Dc for Re of 10 and 100, although the effect of S/Dc on GSD is not evident at various Res. The particle collection efficiency curve of the impactor with a lower Re is less sharp than that with a high Re at various W/Dc and S/Dc values. Statistical equations closely fitted the obtained numerical results for Res of 10-3000. The equations are useful for directly calculating the cutoff aerodynamic diameter and the sharpness of the particle collection efficiency curve for single round-nozzle impactors with a finite impaction Dc.

A novel theoretical model was developed to determine the removal efficiency of sulfur dioxide using fine water spray. The droplet pH, diameter, S(IV) concentration, sulfur dioxide concentration, and liquid-to-gas ratio are found to influence the absorption of sulfur dioxide by the fine water spray. The results demonstrate that the absorption of sulfur dioxide by the fine water spray increases as the droplet diameter falls. The concentration gradient between the interface of the gaseous and liquid phases causes the absorption of sulfur dioxide by the droplets to increase as the initial S(IV) concentration decreases or the sulfur dioxide concentration increases. The results indicate that the performance of the fine water spray in removing sulfur dioxide is generally improved by reducing the droplet diameter or the initial S(IV) concentration, or by increasing the sulfur dioxide concentration, the droplet pH or the liquid-to-gas ratio. The proposed model reveals the parameters that should be controlled in using a fine water spray device and a method for improving its performance in removing sulfur dioxide.

The effect of a porous foam substrate on the penetration characteristics of an impactor with a single round nozzle was investigated experimentally, with liquid and solid particles in the size range of 1–10 m. The experimental results show that the cut-off aerodynamic diameter of the impactor with porous foam substrate is lower than that with porous metal substrate due to more air penetration into the porous foam; in addition, the impactor penetration curve is less sharp. A numerical simulation of the penetration curve for the impactor with porous foam substrate was in good agreement with the experimental data. The numerical method was then used to find the best sampling flow rate for respirable aerosol sampling. Results show that when the nozzle diameter is 0.36 cm and the sampling rate is 1. 9l /min, the penetration curve of the impactor with the porous foam is very close to the criteria for respirable aerosol sampling. 2005 Elsevier Ltd. All rights reserved.

This work presents a novel theoretical model to calculate the removal efficiency of ammonia by fine water spray. The droplet pH, diameter, ammonium concentration, ammonia concentration and liquid-t...

Laboratory and field studies were conducted to evaluate the collection capacity of the nylon filter (Nylasorb membrane, 47 mm diameter, 1.0 µm pore size, Gelman Laboratory, USA) for HCl and HNO3. In ambient sampling, the field results show that one piece of the nylon filter in the filter pack of an annular denuder system (ADS) or a honeycomb denuder system (HDS) has enough capacity to adsorb HCl and HNO3 gases evaporated from the particles collected on the Teflon filter. The laboratory results show that the individual capacity of the nylon filter to adsorb HCl gas is 8, 160, and 240 µg and that of HNO3 gas is 160, 1400, 1900 µg at 20% ± 5%, 55% ± 5%, and 80% ± 5% relative humidity, respectively. At low humidity, the efficiency of the nylon filter for HCl gas will be decreased substantially when HNO3 co‐exists. It is decreased to as little as 35–50% when relative humidity is low, at 20% ± 5% for the added amount of HNO3 is from 40 to 145 µg. A monolayer adsorption theory was successfully employed ...

A method for sampling inorganic acids in the exhaust gas of semiconductor and optoelectronic industries was developed by using a porous metal denuder and an ion chromatograph analysis. The sampler consists of a Teflon filter to collect inorganic acidic aerosols followed by two coated porous metal discs for sampling inorganic acidic gases. The second disc was used to check if the gas broke through the first disc. The method detection limit of the sampler is appropriate for sampling the exhausted gas at semiconductor or photoelectric industries. Test results indicated that the calibration curves had good coefficients of correlation, and the concentrations of the laboratory and field blanks were found to be lower than the method detection limit. For the semiconductor and optoelectronic industries, the total concentration of acidic gases and particles for hydrofluoric acid, hydrochloric acid, nitric acid, phosphoric acid, and sulfuric acid was found to be 85–999, 40–820, 21–223, ND (not detectable)–4...