Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely repo...Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO (5,000 U/kg) 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling (TUNEL) were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.展开更多
To develop a high strength low alloy (HSLA) steel with high strength and high toughness, a series of martensitic steels were studied through alloying with various elements and thermodynamic simulation. The microstru...To develop a high strength low alloy (HSLA) steel with high strength and high toughness, a series of martensitic steels were studied through alloying with various elements and thermodynamic simulation. The microstructure and mechanical properties of the designed steel were investigated by optical microscopy, scanning electron microscopy, tensile testing and Charpy impact test. The results show that cementite exists between 500℃ and 700℃, M7C3 exits below 720℃, and they are much lower than the austenitizing temperature of the designed steel. Furthermore, the Ti(C,N) precipitate exists until 1280℃, which refines the microstructure and increases the strength and toughness. The optimal alloying components are 0.19% C, 1.19% Si, 2.83% Mn, 1.24% Ni, and 0.049% Ti; the tensile strength and the V notch impact toughness of the designed steel are more than 1500 MPa and 100 J, respectively.展开更多
Use of extracorporeal membrane oxygenation to support patients with critical cardiorespiratory illness is increasing.Systemic anticoagulation is an essential element in the care of extracorporeal membrane oxygenation ...Use of extracorporeal membrane oxygenation to support patients with critical cardiorespiratory illness is increasing.Systemic anticoagulation is an essential element in the care of extracorporeal membrane oxygenation patients.While unfractionated heparin is the most commonly used agent,unfractionated heparin is associated with several unique complications that can be catastrophic in critically ill patients,including heparin-induced thrombocytopenia and acquired antithrombin deficiency.These complications can result in thrombotic events and subtherapeutic anticoagulation.Direct thrombin inhibitors(DTIs)are emerging as alternative anticoagulants in patients supported by extracorporeal membrane oxygenation.Increasing evidence supports DTIs use as safe and effective in extracorporeal membrane oxygenation patients with and without heparininduced thrombocytopenia.This review outlines the pharmacology,dosing strategies and available protocols,monitoring parameters,and special use considerations for all available DTIs in extracorporeal membrane oxygenation patients.The advantages and disadvantages of DTIs in extracorporeal membrane oxygenation relative to unfractionated heparin will be described.展开更多
BACKGROUND Assessment of the vascular status following limb fracture in children is important to evaluate the risk of compartment syndrome,which is an emergency condition.AIM To establish a simple and efficient gradin...BACKGROUND Assessment of the vascular status following limb fracture in children is important to evaluate the risk of compartment syndrome,which is an emergency condition.AIM To establish a simple and efficient grading scale of limb perfusion in children undergoing surgery for limb fracture.METHODS This retrospective study included pediatric patients with a limb fracture and postoperative plaster fixation who were admitted at The Department of Pediatric Orthopedics of Xinhua Hospital between February 2017 and August 2017.The outcome was poor limb perfusion,which is defined as the postoperative use of mannitol.The children were divided into two groups:The normal perfusion group and the poor perfusion group.Key risk factors have been selected by univariable analyses to establish the Grading Scale for Vascular Status.RESULTS A total of 161 patients were included in the study:85 in the normal perfusion group and 76 in the poor perfusion group.There were no significant differences in age,sex,body mass index,ethnicity,cause of fracture,fixation,or site of fracture between the two groups.After surgery,the skin temperature(P=0.048)and skin color(P<0.001)of the affected limb were significantly different between the two groups.The relative risk and 95%confidence interval for skin temperature of the affected limb,skin color,and range of motion of the affected limb are 2.18(1.84-2.59),2.89(2.28-3.66),and 2.16(1.83-2.56),respectively.The grading scale was established based on those three factors(score range:0-3 points).Forty-one patients(32.5%)with score 0 had poor limb perfusion;all patients with scores 1(n=32)and 2(n=3)had poor limb perfusion(both 100%).CONCLUSION In children undergoing surgery for limb fracture,a higher Grading Scale for Vascular Status score is associated with a higher occurrence of poor limb perfusion.A prospective study is required for validation.展开更多
文摘Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO (5,000 U/kg) 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling (TUNEL) were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.
基金financially supported by the Scientific Research Foundation of Guangxi University (No.XBZ110407)
文摘To develop a high strength low alloy (HSLA) steel with high strength and high toughness, a series of martensitic steels were studied through alloying with various elements and thermodynamic simulation. The microstructure and mechanical properties of the designed steel were investigated by optical microscopy, scanning electron microscopy, tensile testing and Charpy impact test. The results show that cementite exists between 500℃ and 700℃, M7C3 exits below 720℃, and they are much lower than the austenitizing temperature of the designed steel. Furthermore, the Ti(C,N) precipitate exists until 1280℃, which refines the microstructure and increases the strength and toughness. The optimal alloying components are 0.19% C, 1.19% Si, 2.83% Mn, 1.24% Ni, and 0.049% Ti; the tensile strength and the V notch impact toughness of the designed steel are more than 1500 MPa and 100 J, respectively.
文摘Use of extracorporeal membrane oxygenation to support patients with critical cardiorespiratory illness is increasing.Systemic anticoagulation is an essential element in the care of extracorporeal membrane oxygenation patients.While unfractionated heparin is the most commonly used agent,unfractionated heparin is associated with several unique complications that can be catastrophic in critically ill patients,including heparin-induced thrombocytopenia and acquired antithrombin deficiency.These complications can result in thrombotic events and subtherapeutic anticoagulation.Direct thrombin inhibitors(DTIs)are emerging as alternative anticoagulants in patients supported by extracorporeal membrane oxygenation.Increasing evidence supports DTIs use as safe and effective in extracorporeal membrane oxygenation patients with and without heparininduced thrombocytopenia.This review outlines the pharmacology,dosing strategies and available protocols,monitoring parameters,and special use considerations for all available DTIs in extracorporeal membrane oxygenation patients.The advantages and disadvantages of DTIs in extracorporeal membrane oxygenation relative to unfractionated heparin will be described.
基金Supported by The Hospital-Funded Clinical Research of Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine,No.17CSY01.
文摘BACKGROUND Assessment of the vascular status following limb fracture in children is important to evaluate the risk of compartment syndrome,which is an emergency condition.AIM To establish a simple and efficient grading scale of limb perfusion in children undergoing surgery for limb fracture.METHODS This retrospective study included pediatric patients with a limb fracture and postoperative plaster fixation who were admitted at The Department of Pediatric Orthopedics of Xinhua Hospital between February 2017 and August 2017.The outcome was poor limb perfusion,which is defined as the postoperative use of mannitol.The children were divided into two groups:The normal perfusion group and the poor perfusion group.Key risk factors have been selected by univariable analyses to establish the Grading Scale for Vascular Status.RESULTS A total of 161 patients were included in the study:85 in the normal perfusion group and 76 in the poor perfusion group.There were no significant differences in age,sex,body mass index,ethnicity,cause of fracture,fixation,or site of fracture between the two groups.After surgery,the skin temperature(P=0.048)and skin color(P<0.001)of the affected limb were significantly different between the two groups.The relative risk and 95%confidence interval for skin temperature of the affected limb,skin color,and range of motion of the affected limb are 2.18(1.84-2.59),2.89(2.28-3.66),and 2.16(1.83-2.56),respectively.The grading scale was established based on those three factors(score range:0-3 points).Forty-one patients(32.5%)with score 0 had poor limb perfusion;all patients with scores 1(n=32)and 2(n=3)had poor limb perfusion(both 100%).CONCLUSION In children undergoing surgery for limb fracture,a higher Grading Scale for Vascular Status score is associated with a higher occurrence of poor limb perfusion.A prospective study is required for validation.