CHINA.Yarlung Zangbo Grand Canyon National Nature Reserve.The Yarlung Zangbo Grand Canyon National Nature Reserve,located in Medog of the Xizang Autonomous Region,is one of the most ecologically diverse and visually s...CHINA.Yarlung Zangbo Grand Canyon National Nature Reserve.The Yarlung Zangbo Grand Canyon National Nature Reserve,located in Medog of the Xizang Autonomous Region,is one of the most ecologically diverse and visually stunning protected areas in China.Originally established as the Medog Nature Reserve in 1986,it was renamed in April 2000 to highlight its most prominent natural feature-the Yarlung Zangbo Grand Canyon.展开更多
Ischemic preconditioning and postconditioning distinctly attenuate ventricular arrhythmia after ischemia without affecting the severity of myocardial stunning. Therefore, we report the effects of sevofiurane precondit...Ischemic preconditioning and postconditioning distinctly attenuate ventricular arrhythmia after ischemia without affecting the severity of myocardial stunning. Therefore, we report the effects of sevofiurane preconditioning and postconditioning on stunned myocardium in isolated rat hearts. Isolated rat hearts were underwent 20 min of global ischemia and 40 min of reperfusion. After an equilibration period （20 min）, the hearts in the preconditioning group were exposed to sevoflurane for 5 min and next washout for 5 min before ischemia. Hearts in the sevoflurane postconditioning group underwent equilibration and ischemia, followed immediately by sevoflurane exposure for the first 5 min of reperfusion. The control group received no treatment before and after ischemia. Left ventricular pressure, heart rate, coronary flow, electrocardiogram, and tissue histology were measured as variables of ventricular function and cellular injury, respectively. There was no significant difference in the duration of reperfusion ventricular arrhythmias between control and sevoflurane preconditioning group （P=0.195）. The duration of reperfusion ventricular arrhythmias in the sevoflurane postconditioning group was significantly shorter than that in the other two groups （P〈0.05）. ＋（dPIdt）max in the sevoflurane preconditioning group at 5, 10, 15, 20, and 30 min after reperfusion was significantly higher than that in the control group （P〈0.05）, and there were no significant differences at 40 min after reperfusion among the three groups （P〉0.05）. As expected, for a 20-min general ischemia, infarct size in heart slices determined by 2,3,5-triphenyltetrazolium chloride staining among the groups was not obvious. Sevofiurane postconditioning reduces reperfusion arrhythmias without affecting the severity of myocardial stunning. In contrast, sevoflurane preconditioning has no beneficial effects on reperfusion arrhythmias, but it is in favor of improving ventricular function and recovering myocardial stunning. Sevoflurane preconditioning and postconditioning may be useful for correcting the stunned myocardium.展开更多
Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the ...Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the effect and mechanism of CO_2 stunning on meat color and lipid peroxidation during long-term storage remain poorly studied. We aimed to study the effects of GS methods, especial y CO_2 concentration, on meat color and meat lipid peroxidation in broilers during long-term storage at 4 °C and to explore the potential mechanism of meat color change via lipid peroxidation and the inner lipid peroxide scavenging system.Methods: Eighteen broilers were sacrificed after exposure to one of the following gas mixtures for 90 s: 40% CO_2+21% O_2+ 39% N2(G40%), 79% CO_2+ 21% O_2(G79%), or no stunning(0% CO_2, control). Meat color, serum variables,enzyme activities, and the gene expression of mitogen-activated protein kinase(MAPK), nuclear factor-erythroid2-related factor 2(Nrf2), glutathione S-transferase(GST) and superoxide dismutase(SOD) were determined.(Continued on next page)Results: The concentrations of serum triiodothyronine(T3, P = 0.03) and the ratio of serum free triiodothyronine/free thyroxine(FT3/FT4, P < 0.01) were decreased, whereas levels of serum cortisol(P < 0.01) were increased in the 40%CO_2 group compared with the control group. Additionally, the thiobarbituric acid-reactive substances(TBARS)3 d(P < 0.01) and TBARS6 d(P = 0.01) in breast meat and the TBARS3 din thigh meat(P < 0.01) were increased in the40% CO_2 group compared with the control group. Serum T3 was negatively correlated with TBARS6 dboth in the breast and thigh meat(r =-0.63, P < 0.01 and r =-0.47, P = 0.05 respectively). T3/T4 was negatively correlated with TBARS6 din the breast meat and in the thigh meat(r =-0.57, P = 0.01; and r =-0.53, P = 0.03 respectively). Compared with the control group, Lightness(L*)1 d(P = 0.03) and L*9 d(P < 0.01) were increased, whereas total chromatic aberration(E*)1 d(P = 0.05) and E*3 d(P < 0.01) were decreased in the breast meat of both the G40% and G79% groups. The values of yel owness(b*)3 d(P = 0.01), b*6 d(P < 0.01) and E*6 d(P < 0.01) in the thigh meat were lower in both the G40% and G79% groups than in the control group. In the breast muscle, the m RNA levels of c-Jun N-terminal kinase 2(JNK2, P = 0.03),GSTT1(P = 0.04), and SOD1(P = 0.05) were decreased, and the m RNA levels of JNK1(P = 0.07), Nrf2(P = 0.09), and GSTA3(P = 0.06) were slightly lower in both the G40% and G79% groups compared with the control group. However, among these genes, only the m RNA level of JNK1 was decreased in the G40% group compared with the control group and the G79% group(P = 0.03) in the thigh muscle.Conclusions: Compared with the control group, meat color quality in the breast meat was decreased, and the expression of genes in the MAPK/Nrf2/ARE(antioxidant responsive element) antioxidant pathway in breast muscle was partly suppressed by GS of both 40% and 79% CO_2. However, oxidative stress and meat lipid peroxidation during storage were aggravated by GS with 40% CO_2 compared to GS with 79% CO_2 and no GS.展开更多
Objective To investigate cardiac function and myocardial perfusion during 48 h after cardiopulmonary resuscitation （CPR）, further to test myocardial stunning and seek indicators for long‐term survival after CPR. Me...Objective To investigate cardiac function and myocardial perfusion during 48 h after cardiopulmonary resuscitation （CPR）, further to test myocardial stunning and seek indicators for long‐term survival after CPR. Methods After 4 min of untreated ventricular fibrillation, fifteen anesthetized pigs were studied at baseline and 2 h, 4 h, 24 h, and 48 h after restoration of spontaneous circulation （ROSC）. Hemodynamic data, echocardiography and gated‐single photon emission computed tomography myocardial perfusion images were carried out. Results Mean arterial pressure （MAP）, coronary perfusion pressure （CPP） and cardiac troponin I （CTNI） showed significant differences between eventual survival animals and non‐survival animals at 4 h after ROSC （109.2±10.7 mmHg vs. 94.8±12.3 mmHg, P=0.048; 100.8±6.9 mmHg vs. 84.4±12.6 mmHg, P=0.011; 1.60±0.13 ug/L vs. 1.75±0.10 ug/L, P=0.046）. Mitral valve early‐to‐late diastolic peak velocity ratio, mitral valve deceleration time recovered 24 h; ejection faction and the summed rest score recovered 48 h after ROSC. Conclusion Cardiac systolic and early active relaxation dysfunctions were reversible within survival animals; cardiac stunning might be potentially adaptive and protective after CPR. The recovery of MAP, CPP, and CTNI could be the indicators for long‐term survival after CPR.展开更多
Takotsubo cardiomyopathy is a syndrome mimicking an acute myocardial infarction in absence of obstructive epicardial coronary artery disease to explain the degree of the wall motion abnormalities. Typically more commo...Takotsubo cardiomyopathy is a syndrome mimicking an acute myocardial infarction in absence of obstructive epicardial coronary artery disease to explain the degree of the wall motion abnormalities. Typically more common in the elderly women, this condition is usually triggered by unexpected emotional or physical stress situations, and is associated with electrocardiogram abnormalities and slight elevation of cardiac biomarkers. The pathophysiological mechanism is not clear yet, but it is believed that a high circulating concentration of catecholamines causes an acute dysfunction of the coronary microcirculation and metabolism of cardiomyocytes, leading to a transient myocardial stunning. Typically, it presents with acute left ventricular systolic dysfunction that in most cases is completely resolved at short term. Recurrences are rare and it is thought that the long-term prognosis is good. We present here a review of the clinical features, pathophysiology and management of this enigmatic condition.展开更多
Myocardial infarction(MI)is defined as myocardial cell death due to prolonged myocardial ischemia.Clinically,troponin rise and/or fall have become the“defining feature of MI”according to the universal definition of ...Myocardial infarction(MI)is defined as myocardial cell death due to prolonged myocardial ischemia.Clinically,troponin rise and/or fall have become the“defining feature of MI”according to the universal definition of MI(UD-MI).Takotsubo syndrome(TS)and TS-related disease conditions also cause troponin elevation with typical rise and/or fall pattern but through a mechanism other than coronary ischemia.By strict application of the clinical diagnostic criteria for type-1 MI,type-2 MI,type-3 MI,and MI with non-obstructive coronary arteries according to the UD-MI including the fourth one published recently,TS and most of the 26 other causes of troponin elevation mentioned in the fourth UD-MI may erroneously be classified as MI.The existing evidence argues for the case that TS by itself is not a MI.Hyper-activation of the autonomic-sympathetic nervous system including local cardiac sympathetic hyper-activation and disruption with nor-epinephrine churn and spillover is the most probable cause of TS.This autonomic neuro-cardiogenic(ANCA)mechanism results in myocardial“cramp”(stunning),the severity and duration of which depend on the degree of the sympathetic-hyperactivation and nor-epinephrine spillover.The myocardial cramp may squeeze the cytosolic free troponin pools causing mild to moderate troponin elevation in TS and TS-related disease conditions.This ANCA syndrome,which has hitherto been enveloped by the UD-MI over more than one decade,may occur in acute,recurrent,and chronic forms.In this critical review,the controversies of UD-MI,evidence for ANCA syndrome,and a hypothetical mechanism for the troponin elevation in ANCA syndrome are provided.展开更多
Stress-induced cardiomyopathy,in contrast to acute myocardial infarction,is a type of acute heart failure characterized by reversible left ventricular dysfunction.Cardiac imaging primarily reveals left ventricle myoca...Stress-induced cardiomyopathy,in contrast to acute myocardial infarction,is a type of acute heart failure characterized by reversible left ventricular dysfunction.Cardiac imaging primarily reveals left ventricle myocardial stunning,81.7%of which is apical type.Emotional or psychological stress usually precedes the onset of stress-induced cardiomyopathy,which is increasingly being recognized as a unique neurogenic myocardial stunning disease.To distinguish between acute myocardial infarction and acute viral or auto-immune myocarditis,this review summarizes specific mechanisms of myocardial stunning in stress-induced cardiomyopathy,such as calcium disorders,metabolic alterations,anatomical and histological variations in different parts of the left ventricle,and microvascular dysfunction.展开更多
This is a report of a study on the protective effect of berberine(Ber) on postischemic myocardial stunning and the role it plays in ATPase activity. Isolated working rat hearts were used with global ischemia for 30 mi...This is a report of a study on the protective effect of berberine(Ber) on postischemic myocardial stunning and the role it plays in ATPase activity. Isolated working rat hearts were used with global ischemia for 30 min followed by reperfusing for 40 min. Both systolic and diastolic functions of stunned myocardium were significantly decreased. The recovery of LVSP×HR and CO was 52%±8% and 40%±8% respectively; LVEDP and T were elevated; while both Na +, K +ATPase activity and Ca 2+ , Mg 2+ ATPase activity of myocardial membrane and mitochondria were depressed. Berberine(25 mg·kg -1 ·d -1 , ip, 3 d, and 10 μmol L -1 for isolated heart perfusion) was able to enhance the percent recovery of LVSP×HR and CO to 85%±12% and 75%±11%, respectively, and reduce LVEDP from 298%±64% to 166%±44%, with an improvement in myocardial membrane Na +, K +ATPase activity and mitochondria Ca 2+ , Mg 2+ ATPase activity. This study suggested that berberine can protect cardiac function from ischemia reperfusion stunning injury by preserving ATPase activity in ischemic myocardium.展开更多
Transportation of spent laying hens causes them severe suffering. HAI-MESHEK （The Israeli Society for the Prevention of Cruelty to Farm Animals） looked for ways to decrease the suffering and finally developed the so...Transportation of spent laying hens causes them severe suffering. HAI-MESHEK （The Israeli Society for the Prevention of Cruelty to Farm Animals） looked for ways to decrease the suffering and finally developed the solution. Spent laying hens are brutally taken out of the cages, and with broken legs and chests pressed into small boxes for transportation to the slaughter-house. Removing all hens from the cages, transportation, waiting in the slaughter-house and slaughtering all hens is a long and hard-suffering time, which may take 8-10 hours. Hai-Meshek conducted a research, aimed at finding more humane methods of transportation. The findings from other countries were very disappointing. Even in countries having high level of animal welfare, about 30% of the hens arrived at the slaughter-house with broken limbs! The conclusion was that even better method, imposed by legislation, would not solve the problem： it is difficult to detect truck drivers violating the rules and the fine is negligible, compared to the savings by the abovementioned cruel method. The only humane solution is by preventing the transportation and slaughtering on farm. Spent laying hens are not edible, so they need not be slaughtered in the slaughter-house. Hai-Meshek initiated and participated in the development and the building of a facility for the humane killing of spent laying hens on farms. The hens aye electrified and die in 1-1.5 seconds. This method costs far less than transportation and slaughtering. The Poultry Council, which takes care to remove spent laying hens from farms, requires contractors to use the facility and they bring it to every farm in Israel. The facility is also used for killing sick flocks. No more transportation of spent laying hens is allowed!展开更多
Hypoglycemia is a common complication seen in patients with diabetes mellitus and has been proven to have adverse effects on cardiovascular mortality. Hypoglycemia can potentially lead to worsening of cardiac function...Hypoglycemia is a common complication seen in patients with diabetes mellitus and has been proven to have adverse effects on cardiovascular mortality. Hypoglycemia can potentially lead to worsening of cardiac function in patients with ischemic heart disease. We present a case of cardiogenic shock in a patient with hypoglycemia secondary to insulin accumulation due to worsening renal function with dramatic recovery of shock once his sugars normalized.展开更多
When you hear about boundless grasslands,vast forests,stunning snowy landscapes,bubbling hot springs and cultural integration,do you ever consider they are descriptions-features actually-of one place?They are,believe ...When you hear about boundless grasslands,vast forests,stunning snowy landscapes,bubbling hot springs and cultural integration,do you ever consider they are descriptions-features actually-of one place?They are,believe it or not.Arxan,a tiny city in Hinggan League,North China's Inner Mongolia Autonomous Region,is that magical place.In recent years,Arxan,a hidden gem boasting breathtaking winter landscape,has captivated visitors seeking to enjoy a“pure-white,fairy-tale world.”展开更多
Objective To identify predictors of left atrial appendage stunning after the use of electrical cardioversion to restore sinus rhythm in patients with non-valvular atrial fibrillation. Methods A total of 68 consecutive...Objective To identify predictors of left atrial appendage stunning after the use of electrical cardioversion to restore sinus rhythm in patients with non-valvular atrial fibrillation. Methods A total of 68 consecutive patients (45 men,23 women,60.5±8.7 years of age) with non-valvular atrial fibrillation undergoing electrical cardioversion were enlisted in this study. Clinical and echocardiographic variables were analyzed by univariate regression and multivariate logistic regression to investigate the relationship between occurrences of left atrial appendage stunning and these factors. Results Univariate analysis revealed that,in comparing patients without and with left atrial appendage stunning,there were significant differences in the duration of atrial fibrillation > 8 weeks (32.3% vs 75.5%,P <0.001),left atrial diameter > 50 mm (29.0% vs 54.1%,P <0.05),left atrial emptying fraction (31.5%±7.8% vs 27.1%±8.5%,P <0.05),left ventricular ejection fraction < 50% (38.7% vs 67.6%,P <0.05),maximum electrical energy (96.8 J±65.8 J vs 156.8 J±100.8 J,P <0.01),cumulative electrical energy 146.8 J±142.6 J vs 290.5 J±242.1 J, P <0.01) and number of electrical cardioversion shocks (1.7±0.9 vs 2.43±1.20,P <0.05). However,backward stepwise multivariate logistic regression analysis identified as significant and independent predictors of left atrial appendage stunning only duration of atrial fibrillation > 8 weeks (OR=7.249,95%CI=1.998-26.304, P <0.01),left atrial diameter > 50 mm (OR=3.896,95%CI=1.105-13.734,P <0.05),left ventricular ejection fraction < 50% (OR=4.465,95%CI=1.51713.140, P <0.01) and cumulative energy of electrical cardioversion (OR=1.004,95%CI=1.000-1.008, P <0.05). Conclusions Duration of atrial fibrillation >8 weeks,left atrial diameter >50 mm,left ventricular ejection fraction <50%,and cumulative energy of electrical cardioversion are independent predictors of left atrial appendage stunning. Anticoagulation treatment should be individualized for patients undergoing electrical cardioversion to reduce the risk of both cardioversion-related thromboembolic events and hemorrhagic complications caused by warfarin treatment.展开更多
In recent years,China has made considerable efforts toward ecological and environmental protection.The government has introduced a series of environmental protection laws and regulations targeting water,soil and air p...In recent years,China has made considerable efforts toward ecological and environmental protection.The government has introduced a series of environmental protection laws and regulations targeting water,soil and air pollution,with signs of progress evident across the country.展开更多
文摘CHINA.Yarlung Zangbo Grand Canyon National Nature Reserve.The Yarlung Zangbo Grand Canyon National Nature Reserve,located in Medog of the Xizang Autonomous Region,is one of the most ecologically diverse and visually stunning protected areas in China.Originally established as the Medog Nature Reserve in 1986,it was renamed in April 2000 to highlight its most prominent natural feature-the Yarlung Zangbo Grand Canyon.
基金Project supported by the National Natural Science Foundation of China (No. 30772090)the Natural Science Foundation of Zhejiang Province (No. Y204141)+1 种基金the Foundation from Science and Tech-nology Department of Zhejiang Province (No. 2007R10034)the Foundation from the Health Bureau of Zhejiang Province (No. 2007QN007), China
文摘Ischemic preconditioning and postconditioning distinctly attenuate ventricular arrhythmia after ischemia without affecting the severity of myocardial stunning. Therefore, we report the effects of sevofiurane preconditioning and postconditioning on stunned myocardium in isolated rat hearts. Isolated rat hearts were underwent 20 min of global ischemia and 40 min of reperfusion. After an equilibration period （20 min）, the hearts in the preconditioning group were exposed to sevoflurane for 5 min and next washout for 5 min before ischemia. Hearts in the sevoflurane postconditioning group underwent equilibration and ischemia, followed immediately by sevoflurane exposure for the first 5 min of reperfusion. The control group received no treatment before and after ischemia. Left ventricular pressure, heart rate, coronary flow, electrocardiogram, and tissue histology were measured as variables of ventricular function and cellular injury, respectively. There was no significant difference in the duration of reperfusion ventricular arrhythmias between control and sevoflurane preconditioning group （P=0.195）. The duration of reperfusion ventricular arrhythmias in the sevoflurane postconditioning group was significantly shorter than that in the other two groups （P〈0.05）. ＋（dPIdt）max in the sevoflurane preconditioning group at 5, 10, 15, 20, and 30 min after reperfusion was significantly higher than that in the control group （P〈0.05）, and there were no significant differences at 40 min after reperfusion among the three groups （P〉0.05）. As expected, for a 20-min general ischemia, infarct size in heart slices determined by 2,3,5-triphenyltetrazolium chloride staining among the groups was not obvious. Sevofiurane postconditioning reduces reperfusion arrhythmias without affecting the severity of myocardial stunning. In contrast, sevoflurane preconditioning has no beneficial effects on reperfusion arrhythmias, but it is in favor of improving ventricular function and recovering myocardial stunning. Sevoflurane preconditioning and postconditioning may be useful for correcting the stunned myocardium.
基金financed by the National Natural Science Foundation of China(NSFC)(31601978)the China Agriculture Research System-Beijing Team for Poultry Industrythe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the effect and mechanism of CO_2 stunning on meat color and lipid peroxidation during long-term storage remain poorly studied. We aimed to study the effects of GS methods, especial y CO_2 concentration, on meat color and meat lipid peroxidation in broilers during long-term storage at 4 °C and to explore the potential mechanism of meat color change via lipid peroxidation and the inner lipid peroxide scavenging system.Methods: Eighteen broilers were sacrificed after exposure to one of the following gas mixtures for 90 s: 40% CO_2+21% O_2+ 39% N2(G40%), 79% CO_2+ 21% O_2(G79%), or no stunning(0% CO_2, control). Meat color, serum variables,enzyme activities, and the gene expression of mitogen-activated protein kinase(MAPK), nuclear factor-erythroid2-related factor 2(Nrf2), glutathione S-transferase(GST) and superoxide dismutase(SOD) were determined.(Continued on next page)Results: The concentrations of serum triiodothyronine(T3, P = 0.03) and the ratio of serum free triiodothyronine/free thyroxine(FT3/FT4, P < 0.01) were decreased, whereas levels of serum cortisol(P < 0.01) were increased in the 40%CO_2 group compared with the control group. Additionally, the thiobarbituric acid-reactive substances(TBARS)3 d(P < 0.01) and TBARS6 d(P = 0.01) in breast meat and the TBARS3 din thigh meat(P < 0.01) were increased in the40% CO_2 group compared with the control group. Serum T3 was negatively correlated with TBARS6 dboth in the breast and thigh meat(r =-0.63, P < 0.01 and r =-0.47, P = 0.05 respectively). T3/T4 was negatively correlated with TBARS6 din the breast meat and in the thigh meat(r =-0.57, P = 0.01; and r =-0.53, P = 0.03 respectively). Compared with the control group, Lightness(L*)1 d(P = 0.03) and L*9 d(P < 0.01) were increased, whereas total chromatic aberration(E*)1 d(P = 0.05) and E*3 d(P < 0.01) were decreased in the breast meat of both the G40% and G79% groups. The values of yel owness(b*)3 d(P = 0.01), b*6 d(P < 0.01) and E*6 d(P < 0.01) in the thigh meat were lower in both the G40% and G79% groups than in the control group. In the breast muscle, the m RNA levels of c-Jun N-terminal kinase 2(JNK2, P = 0.03),GSTT1(P = 0.04), and SOD1(P = 0.05) were decreased, and the m RNA levels of JNK1(P = 0.07), Nrf2(P = 0.09), and GSTA3(P = 0.06) were slightly lower in both the G40% and G79% groups compared with the control group. However, among these genes, only the m RNA level of JNK1 was decreased in the G40% group compared with the control group and the G79% group(P = 0.03) in the thigh muscle.Conclusions: Compared with the control group, meat color quality in the breast meat was decreased, and the expression of genes in the MAPK/Nrf2/ARE(antioxidant responsive element) antioxidant pathway in breast muscle was partly suppressed by GS of both 40% and 79% CO_2. However, oxidative stress and meat lipid peroxidation during storage were aggravated by GS with 40% CO_2 compared to GS with 79% CO_2 and no GS.
基金supported by the National Natural Science Foundation of China (No. 30972863)
文摘Objective To investigate cardiac function and myocardial perfusion during 48 h after cardiopulmonary resuscitation （CPR）, further to test myocardial stunning and seek indicators for long‐term survival after CPR. Methods After 4 min of untreated ventricular fibrillation, fifteen anesthetized pigs were studied at baseline and 2 h, 4 h, 24 h, and 48 h after restoration of spontaneous circulation （ROSC）. Hemodynamic data, echocardiography and gated‐single photon emission computed tomography myocardial perfusion images were carried out. Results Mean arterial pressure （MAP）, coronary perfusion pressure （CPP） and cardiac troponin I （CTNI） showed significant differences between eventual survival animals and non‐survival animals at 4 h after ROSC （109.2±10.7 mmHg vs. 94.8±12.3 mmHg, P=0.048; 100.8±6.9 mmHg vs. 84.4±12.6 mmHg, P=0.011; 1.60±0.13 ug/L vs. 1.75±0.10 ug/L, P=0.046）. Mitral valve early‐to‐late diastolic peak velocity ratio, mitral valve deceleration time recovered 24 h; ejection faction and the summed rest score recovered 48 h after ROSC. Conclusion Cardiac systolic and early active relaxation dysfunctions were reversible within survival animals; cardiac stunning might be potentially adaptive and protective after CPR. The recovery of MAP, CPP, and CTNI could be the indicators for long‐term survival after CPR.
文摘Takotsubo cardiomyopathy is a syndrome mimicking an acute myocardial infarction in absence of obstructive epicardial coronary artery disease to explain the degree of the wall motion abnormalities. Typically more common in the elderly women, this condition is usually triggered by unexpected emotional or physical stress situations, and is associated with electrocardiogram abnormalities and slight elevation of cardiac biomarkers. The pathophysiological mechanism is not clear yet, but it is believed that a high circulating concentration of catecholamines causes an acute dysfunction of the coronary microcirculation and metabolism of cardiomyocytes, leading to a transient myocardial stunning. Typically, it presents with acute left ventricular systolic dysfunction that in most cases is completely resolved at short term. Recurrences are rare and it is thought that the long-term prognosis is good. We present here a review of the clinical features, pathophysiology and management of this enigmatic condition.
文摘Myocardial infarction(MI)is defined as myocardial cell death due to prolonged myocardial ischemia.Clinically,troponin rise and/or fall have become the“defining feature of MI”according to the universal definition of MI(UD-MI).Takotsubo syndrome(TS)and TS-related disease conditions also cause troponin elevation with typical rise and/or fall pattern but through a mechanism other than coronary ischemia.By strict application of the clinical diagnostic criteria for type-1 MI,type-2 MI,type-3 MI,and MI with non-obstructive coronary arteries according to the UD-MI including the fourth one published recently,TS and most of the 26 other causes of troponin elevation mentioned in the fourth UD-MI may erroneously be classified as MI.The existing evidence argues for the case that TS by itself is not a MI.Hyper-activation of the autonomic-sympathetic nervous system including local cardiac sympathetic hyper-activation and disruption with nor-epinephrine churn and spillover is the most probable cause of TS.This autonomic neuro-cardiogenic(ANCA)mechanism results in myocardial“cramp”(stunning),the severity and duration of which depend on the degree of the sympathetic-hyperactivation and nor-epinephrine spillover.The myocardial cramp may squeeze the cytosolic free troponin pools causing mild to moderate troponin elevation in TS and TS-related disease conditions.This ANCA syndrome,which has hitherto been enveloped by the UD-MI over more than one decade,may occur in acute,recurrent,and chronic forms.In this critical review,the controversies of UD-MI,evidence for ANCA syndrome,and a hypothetical mechanism for the troponin elevation in ANCA syndrome are provided.
基金supported primarily by the Distinguished Young Foundations of the First Affiliated Hospital of Harbin Medical University(HYD2020JQ002 to Dr Yin)The Science Foundation of the First Affiliated Hospital of Harbin Medical University(2018 L001 to Dr Yin).
文摘Stress-induced cardiomyopathy,in contrast to acute myocardial infarction,is a type of acute heart failure characterized by reversible left ventricular dysfunction.Cardiac imaging primarily reveals left ventricle myocardial stunning,81.7%of which is apical type.Emotional or psychological stress usually precedes the onset of stress-induced cardiomyopathy,which is increasingly being recognized as a unique neurogenic myocardial stunning disease.To distinguish between acute myocardial infarction and acute viral or auto-immune myocarditis,this review summarizes specific mechanisms of myocardial stunning in stress-induced cardiomyopathy,such as calcium disorders,metabolic alterations,anatomical and histological variations in different parts of the left ventricle,and microvascular dysfunction.
文摘This is a report of a study on the protective effect of berberine(Ber) on postischemic myocardial stunning and the role it plays in ATPase activity. Isolated working rat hearts were used with global ischemia for 30 min followed by reperfusing for 40 min. Both systolic and diastolic functions of stunned myocardium were significantly decreased. The recovery of LVSP×HR and CO was 52%±8% and 40%±8% respectively; LVEDP and T were elevated; while both Na +, K +ATPase activity and Ca 2+ , Mg 2+ ATPase activity of myocardial membrane and mitochondria were depressed. Berberine(25 mg·kg -1 ·d -1 , ip, 3 d, and 10 μmol L -1 for isolated heart perfusion) was able to enhance the percent recovery of LVSP×HR and CO to 85%±12% and 75%±11%, respectively, and reduce LVEDP from 298%±64% to 166%±44%, with an improvement in myocardial membrane Na +, K +ATPase activity and mitochondria Ca 2+ , Mg 2+ ATPase activity. This study suggested that berberine can protect cardiac function from ischemia reperfusion stunning injury by preserving ATPase activity in ischemic myocardium.
文摘Transportation of spent laying hens causes them severe suffering. HAI-MESHEK （The Israeli Society for the Prevention of Cruelty to Farm Animals） looked for ways to decrease the suffering and finally developed the solution. Spent laying hens are brutally taken out of the cages, and with broken legs and chests pressed into small boxes for transportation to the slaughter-house. Removing all hens from the cages, transportation, waiting in the slaughter-house and slaughtering all hens is a long and hard-suffering time, which may take 8-10 hours. Hai-Meshek conducted a research, aimed at finding more humane methods of transportation. The findings from other countries were very disappointing. Even in countries having high level of animal welfare, about 30% of the hens arrived at the slaughter-house with broken limbs! The conclusion was that even better method, imposed by legislation, would not solve the problem： it is difficult to detect truck drivers violating the rules and the fine is negligible, compared to the savings by the abovementioned cruel method. The only humane solution is by preventing the transportation and slaughtering on farm. Spent laying hens are not edible, so they need not be slaughtered in the slaughter-house. Hai-Meshek initiated and participated in the development and the building of a facility for the humane killing of spent laying hens on farms. The hens aye electrified and die in 1-1.5 seconds. This method costs far less than transportation and slaughtering. The Poultry Council, which takes care to remove spent laying hens from farms, requires contractors to use the facility and they bring it to every farm in Israel. The facility is also used for killing sick flocks. No more transportation of spent laying hens is allowed!
文摘Hypoglycemia is a common complication seen in patients with diabetes mellitus and has been proven to have adverse effects on cardiovascular mortality. Hypoglycemia can potentially lead to worsening of cardiac function in patients with ischemic heart disease. We present a case of cardiogenic shock in a patient with hypoglycemia secondary to insulin accumulation due to worsening renal function with dramatic recovery of shock once his sugars normalized.
文摘When you hear about boundless grasslands,vast forests,stunning snowy landscapes,bubbling hot springs and cultural integration,do you ever consider they are descriptions-features actually-of one place?They are,believe it or not.Arxan,a tiny city in Hinggan League,North China's Inner Mongolia Autonomous Region,is that magical place.In recent years,Arxan,a hidden gem boasting breathtaking winter landscape,has captivated visitors seeking to enjoy a“pure-white,fairy-tale world.”
文摘Objective To identify predictors of left atrial appendage stunning after the use of electrical cardioversion to restore sinus rhythm in patients with non-valvular atrial fibrillation. Methods A total of 68 consecutive patients (45 men,23 women,60.5±8.7 years of age) with non-valvular atrial fibrillation undergoing electrical cardioversion were enlisted in this study. Clinical and echocardiographic variables were analyzed by univariate regression and multivariate logistic regression to investigate the relationship between occurrences of left atrial appendage stunning and these factors. Results Univariate analysis revealed that,in comparing patients without and with left atrial appendage stunning,there were significant differences in the duration of atrial fibrillation > 8 weeks (32.3% vs 75.5%,P <0.001),left atrial diameter > 50 mm (29.0% vs 54.1%,P <0.05),left atrial emptying fraction (31.5%±7.8% vs 27.1%±8.5%,P <0.05),left ventricular ejection fraction < 50% (38.7% vs 67.6%,P <0.05),maximum electrical energy (96.8 J±65.8 J vs 156.8 J±100.8 J,P <0.01),cumulative electrical energy 146.8 J±142.6 J vs 290.5 J±242.1 J, P <0.01) and number of electrical cardioversion shocks (1.7±0.9 vs 2.43±1.20,P <0.05). However,backward stepwise multivariate logistic regression analysis identified as significant and independent predictors of left atrial appendage stunning only duration of atrial fibrillation > 8 weeks (OR=7.249,95%CI=1.998-26.304, P <0.01),left atrial diameter > 50 mm (OR=3.896,95%CI=1.105-13.734,P <0.05),left ventricular ejection fraction < 50% (OR=4.465,95%CI=1.51713.140, P <0.01) and cumulative energy of electrical cardioversion (OR=1.004,95%CI=1.000-1.008, P <0.05). Conclusions Duration of atrial fibrillation >8 weeks,left atrial diameter >50 mm,left ventricular ejection fraction <50%,and cumulative energy of electrical cardioversion are independent predictors of left atrial appendage stunning. Anticoagulation treatment should be individualized for patients undergoing electrical cardioversion to reduce the risk of both cardioversion-related thromboembolic events and hemorrhagic complications caused by warfarin treatment.
文摘In recent years,China has made considerable efforts toward ecological and environmental protection.The government has introduced a series of environmental protection laws and regulations targeting water,soil and air pollution,with signs of progress evident across the country.
