TiO2 nanoparticles were homogeneously coated on multi-walled carbon nanotubes by hydrothermal deposition, this nanocomposite may be a promising material for myoglobin immobilization in view of its high biocompatibilit...TiO2 nanoparticles were homogeneously coated on multi-walled carbon nanotubes by hydrothermal deposition, this nanocomposite may be a promising material for myoglobin immobilization in view of its high biocompatibility and large surface. The glassy carbon electrode modified with Mb-TiO2/MWCNTs films exhibited a pair of weU defined, stable and nearly reversible cycle voltammetric peaks. The electron transfer between Mb and electrode surface, Ks of 3.08 s^-1, was greatly facilitated in the TiO2/ MWCNTs film. The electrocatalytic reductions of hydrogen peroxide were studied, the apparent Michaelis-Menten constant is calculated to be 83.10 μmol/L, which shows a large catalytic activity of Mb in the TiO2/MWCNTs film to H2O2.展开更多
Background:Acute kidney injury(AKI)is the main life-threatening complication of crush syndrome(CS),and myoglobin is accepted as the main pathogenic factor.The pattern recognition receptor retinoicacid-inducible gene I...Background:Acute kidney injury(AKI)is the main life-threatening complication of crush syndrome(CS),and myoglobin is accepted as the main pathogenic factor.The pattern recognition receptor retinoicacid-inducible gene I(RIG-I)has been reported to exert anti-viral effects function in the innate immune response.However,it is not clear whether RIG-I plays a role in CS-AKI.The present research was carried out to explore the role of RIG-I in CS-AKI.Methods:Sprague-Dawley rats were randomly divided into two groups:the sham and CS groups(n=12).After administration of anesthesia,the double hind limbs of rats in the CS group were put under a pressure of 3 kg for 16 h to mimic crush conditions.The rats in both groups were denied access to food and water.Rats were sacrificed at 12 h or 36 h after pressure was relieved.The successful establishment of the CS-AKI model was confirmed by serum biochemical analysis and renal histological examination.In addition,RNA sequencing was performed on rat kidney tissue to identify molecular pathways involved in CS-AKI.Furthermore,NRK-52 E cells were treated with 200μmol/L ferrous myoglobin to mimic CS-AKI at the cellular level.The cells and cell supernatant samples were collected at 6 h or 24 h.Small interfering RNAs(siRNA)was used to knock down RIG-I expression.The relative expression levels of molecules involved in the RIG-I pathway in rat kidney or cells samples were measured by quantitative real-time PCR(qPCR),Western blotting analysis,and immunohistochemistry(IHC)staining.Tumor necrosis factor-α(TNF-α)was d etected by ELISA.Co-immunoprecipitation(Co-IP)assays were used to detect the interaction between RIG-I and myoglobin.Results:RNA sequencing of CS-AKI rat kidney tissue revealed that the different expression of RIG-I signaling pathway.qPCR,Western blotting,and IHC assays showed that RIG-I,nuclear factor kappa-B(NF-κB)P65,p-P65,and the a poptotic marker caspase-3 and cleaved caspase-3 were up-regulated in the CS group(P<0.05).However,the levels of interferon regulatory factor 3(IRF3),p-IRF3 and the antiviral factor interferon-beta(IFN-β)showed no significant c hanges between the sham and CS groups.Co-IP assays showed the interaction between RIG-I and myoglobin in the kidneys of the CS group.Depletion of RIG-I could alleviate the myoglobin induced expression of apoptosis-associated molecules via the NF-κB/caspase-3 axis.C onclusions:RIG-I is a novel damage-associated molecular patterns(DAMPs)sensor for myoglobin and participates in the NF-κB/caspase-3 signaling pathway in CS-AKI.In the development of CS-AKI,specific intervention in the RIG-I p athway might be a potential therapeutic strategy for CS-AKI.展开更多
Ordered films were made by casting a mixture of aqueous dispersions of didodecyldimethylammonium bromide (DDAB)-clay composite and myoglobin (Mb) solution on pyrolytic graphite (PG) electrodes. The Mb-DDAB-clay film e...Ordered films were made by casting a mixture of aqueous dispersions of didodecyldimethylammonium bromide (DDAB)-clay composite and myoglobin (Mb) solution on pyrolytic graphite (PG) electrodes. The Mb-DDAB-clay film electrodes showed stable and reversible cyclic voltammetric responses in buffers and can catalyze the reduction of id (TCA).展开更多
The characteristic of Myoglobin as mimetic enzyme was studied and applied in the determination of HeO2 with o-phenylenediamine as substrate. The absorbanee obtained at 40 ℃ was found to be proportional to the concent...The characteristic of Myoglobin as mimetic enzyme was studied and applied in the determination of HeO2 with o-phenylenediamine as substrate. The absorbanee obtained at 40 ℃ was found to be proportional to the concentration of H2O2 in the range of 2.0×10^-5- 2.0×10^-7 mol/L, with a correlation coefficient of 0.999 1. The proposed meth od is simple and highly sensitive to a detection limit of 2.7 × 10^-8 mol/L. The relative standard deviations were within 5% for the determination of different concentrations of H2O2. Satisfied results were obtained in the determination of H2O2 in rainwater by this method, and the recoveries were at the range of 97.2%-105.4%.展开更多
Background: The possibility exists that cocaine use in the absence of frank clinical presentation of acute cardiac events may be associated with subclinical injury including the release of myoglobin which is a nonspec...Background: The possibility exists that cocaine use in the absence of frank clinical presentation of acute cardiac events may be associated with subclinical injury including the release of myoglobin which is a nonspecific marker for cardiac and skeletal muscle damage. Objectives: This investigation examined urine specimens for potential differences between cocaine use and the expression of myoglobin (a marker associated with cardiovascular damage, inflammation and oxidative stress). Methods:40 urine specimens were assayed for cocaine metabolites, creatinine, total protein (BSA) and myoglobin using ELISA and colorimetry. Results: We observed significant differences between male control and male cocaine positive urines for myoglobin. Interestingly, there was no statistically significant difference in females between control and cocaine positive urines. Conclusion: Differences in the urinary expression of myoglobin may be important in evaluating the gender based effects of cocaine use and may have potential clinical applications which may be related to gender differences in signs and symptoms of cocaine toxicity.展开更多
BACKGROUND:Heatstroke has become a common emergency event in hospitals.Procalcitonin(PCT)is used as a biomarker of infection in the emergency department(ED),but its role in rhabdomyolysis(RM)following exertional heats...BACKGROUND:Heatstroke has become a common emergency event in hospitals.Procalcitonin(PCT)is used as a biomarker of infection in the emergency department(ED),but its role in rhabdomyolysis(RM)following exertional heatstroke(EHS)remains unclear.METHODS:A retrospective cohort study enrolled patients with EHS from the intensive care unit(ICU).We collected RM biomarkers,inflammation markers,critical disease scores at admission,24 h,48 h,and discharge,and 90-day mortality.Correlation analysis,linear regression and curve fi tting were used to identify the relationship between PCT and RM.RESULTS:A total of 162 patients were recruited and divided into RM(n=56)and non-RM(n=106)groups.PCT was positively correlated with myoglobin(Mb),acute hepatic injury,disseminated intravascular coagulation(DIC),Sequential Organ Failure Assessment(SOFA)score,and Acute Physiology and Chronic Health Evaluation II(APACHE II)score,with correlation coefficients of 0.214,0.237,0.285,0.454,and 0.368,respectively(all P<0.05).Interestingly,the results of curve fi tting revealed a nonlinear relationship between PCT and RM,and a two-piecewise linear regression model showed that PCT was related to RM with an odds ratio of 1.3 and a cut-off of<4.6 ng/mL.Survival analysis revealed that RM was associated with higher mortality compared to non-RM cases(P=0.0093).CONCLUSION:High serum PCT concentrations are associated with RM after EHS in critically ill patients.Elevated PCT concentrations should be interpreted cautiously in patients with EHS in the ED.展开更多
Background: The exRML (exertional rhabdomyolysis) is a pathophysiologic condition of skeletal muscle cell damage and breakdown associated with high intensity or prolonged exercise, normal exercise under extreme circum...Background: The exRML (exertional rhabdomyolysis) is a pathophysiologic condition of skeletal muscle cell damage and breakdown associated with high intensity or prolonged exercise, normal exercise under extreme circumstances, or sudden and excessive skeletal muscle contraction. It may manifest from the increase in CK (creatine kinase) or MYO (myoglobin), a protein that can cause life-threatening injury to the kidney (AKI, acute kidney injury), and may or may not be associated with myoglobinuria. Here, we presented a case of exRML with AKI, and then reviewed the related reports. Vigorous hydration, sodium bicarbonate and furosemide are key treatments. Aim: To examine an elderly patient with exRML induced AKI and the key treatment process. Case summary: A 61-year-old man left our hospital without permission after his admission and has been walking for almost 30 kms with no water and food intake, then was diagnosed exRML and exRML induced AKI with an obvious elevation of CK, MYO and decrease of eGFR (estimated glomerular filtration rate) after coming back, and was treated with vigorous hydration, loop diuresis, sodium bicarbonate, prostaglandin and Shenkang injection. After vigorous resuscitation, the patient’s renal function, CK and MYO returned normal. Conclusions: The exRML can cause serious complications such as AKI and death. Delayed diagnosis can be critical;therefore, manner of time should be taken to achieve a favorable prognosis.展开更多
By retaining the native distal His64 in sperm whale myoglobin （Mb）, a second distal histidine was engineered in Mb by mutating Leu29 to His29. The resultant mutant of L29H Mb exhibits an unusual enhanced peroxidase ...By retaining the native distal His64 in sperm whale myoglobin （Mb）, a second distal histidine was engineered in Mb by mutating Leu29 to His29. The resultant mutant of L29H Mb exhibits an unusual enhanced peroxidase activity with a positive cooperativity in comparison to that of wild type Mb. The new enzyme with two cooperative distal histidines has not been found in native peroxidase, which emohasizes a creation of the rational nmt^in doclan展开更多
基金the National Natural Science Foundation of China(No.20635020,90606016)
文摘TiO2 nanoparticles were homogeneously coated on multi-walled carbon nanotubes by hydrothermal deposition, this nanocomposite may be a promising material for myoglobin immobilization in view of its high biocompatibility and large surface. The glassy carbon electrode modified with Mb-TiO2/MWCNTs films exhibited a pair of weU defined, stable and nearly reversible cycle voltammetric peaks. The electron transfer between Mb and electrode surface, Ks of 3.08 s^-1, was greatly facilitated in the TiO2/ MWCNTs film. The electrocatalytic reductions of hydrogen peroxide were studied, the apparent Michaelis-Menten constant is calculated to be 83.10 μmol/L, which shows a large catalytic activity of Mb in the TiO2/MWCNTs film to H2O2.
基金supported by the Tianjin UniversityaDouble First Classoconstruction talent start-up fund to Dr.Yan-Hua Gong,the grants awarded to Shi-Ke Hou by Science and Technology Commission of the CMC(c12019048)Ning Li by Open Fund of State Key Laboratory of Medicinal Chemical Biology(Nankai University)(2020010)。
文摘Background:Acute kidney injury(AKI)is the main life-threatening complication of crush syndrome(CS),and myoglobin is accepted as the main pathogenic factor.The pattern recognition receptor retinoicacid-inducible gene I(RIG-I)has been reported to exert anti-viral effects function in the innate immune response.However,it is not clear whether RIG-I plays a role in CS-AKI.The present research was carried out to explore the role of RIG-I in CS-AKI.Methods:Sprague-Dawley rats were randomly divided into two groups:the sham and CS groups(n=12).After administration of anesthesia,the double hind limbs of rats in the CS group were put under a pressure of 3 kg for 16 h to mimic crush conditions.The rats in both groups were denied access to food and water.Rats were sacrificed at 12 h or 36 h after pressure was relieved.The successful establishment of the CS-AKI model was confirmed by serum biochemical analysis and renal histological examination.In addition,RNA sequencing was performed on rat kidney tissue to identify molecular pathways involved in CS-AKI.Furthermore,NRK-52 E cells were treated with 200μmol/L ferrous myoglobin to mimic CS-AKI at the cellular level.The cells and cell supernatant samples were collected at 6 h or 24 h.Small interfering RNAs(siRNA)was used to knock down RIG-I expression.The relative expression levels of molecules involved in the RIG-I pathway in rat kidney or cells samples were measured by quantitative real-time PCR(qPCR),Western blotting analysis,and immunohistochemistry(IHC)staining.Tumor necrosis factor-α(TNF-α)was d etected by ELISA.Co-immunoprecipitation(Co-IP)assays were used to detect the interaction between RIG-I and myoglobin.Results:RNA sequencing of CS-AKI rat kidney tissue revealed that the different expression of RIG-I signaling pathway.qPCR,Western blotting,and IHC assays showed that RIG-I,nuclear factor kappa-B(NF-κB)P65,p-P65,and the a poptotic marker caspase-3 and cleaved caspase-3 were up-regulated in the CS group(P<0.05).However,the levels of interferon regulatory factor 3(IRF3),p-IRF3 and the antiviral factor interferon-beta(IFN-β)showed no significant c hanges between the sham and CS groups.Co-IP assays showed the interaction between RIG-I and myoglobin in the kidneys of the CS group.Depletion of RIG-I could alleviate the myoglobin induced expression of apoptosis-associated molecules via the NF-κB/caspase-3 axis.C onclusions:RIG-I is a novel damage-associated molecular patterns(DAMPs)sensor for myoglobin and participates in the NF-κB/caspase-3 signaling pathway in CS-AKI.In the development of CS-AKI,specific intervention in the RIG-I p athway might be a potential therapeutic strategy for CS-AKI.
文摘Ordered films were made by casting a mixture of aqueous dispersions of didodecyldimethylammonium bromide (DDAB)-clay composite and myoglobin (Mb) solution on pyrolytic graphite (PG) electrodes. The Mb-DDAB-clay film electrodes showed stable and reversible cyclic voltammetric responses in buffers and can catalyze the reduction of id (TCA).
基金Supported by the National Natural Science Foun-dation of China (20275027) the Natural Science Foundation ofHubei Province (2004ABA182) .
文摘The characteristic of Myoglobin as mimetic enzyme was studied and applied in the determination of HeO2 with o-phenylenediamine as substrate. The absorbanee obtained at 40 ℃ was found to be proportional to the concentration of H2O2 in the range of 2.0×10^-5- 2.0×10^-7 mol/L, with a correlation coefficient of 0.999 1. The proposed meth od is simple and highly sensitive to a detection limit of 2.7 × 10^-8 mol/L. The relative standard deviations were within 5% for the determination of different concentrations of H2O2. Satisfied results were obtained in the determination of H2O2 in rainwater by this method, and the recoveries were at the range of 97.2%-105.4%.
文摘Background: The possibility exists that cocaine use in the absence of frank clinical presentation of acute cardiac events may be associated with subclinical injury including the release of myoglobin which is a nonspecific marker for cardiac and skeletal muscle damage. Objectives: This investigation examined urine specimens for potential differences between cocaine use and the expression of myoglobin (a marker associated with cardiovascular damage, inflammation and oxidative stress). Methods:40 urine specimens were assayed for cocaine metabolites, creatinine, total protein (BSA) and myoglobin using ELISA and colorimetry. Results: We observed significant differences between male control and male cocaine positive urines for myoglobin. Interestingly, there was no statistically significant difference in females between control and cocaine positive urines. Conclusion: Differences in the urinary expression of myoglobin may be important in evaluating the gender based effects of cocaine use and may have potential clinical applications which may be related to gender differences in signs and symptoms of cocaine toxicity.
基金funded by the National Natural Science Foundation of China(82072143,81873943,82360903)Sanming Project of Medicine in Shenzhen(SZSM20162011)+3 种基金Shenzhen Science and Technology Innovation Commission(JCYJ20190806163603504)Shenzhen Second People’s Hospital Clinical Research Fund of Guangdong Province High-level Hospital Construction Project(20203357014,2023xgyj3357001,2023yjlcyj022)Guizhou Science and Technology Planning Project(Guizhou Science and Technology Cooperation Support[2021]General 413)and PhD Start-up Fund(GYZYYFY-BS-2023[09]).
文摘BACKGROUND:Heatstroke has become a common emergency event in hospitals.Procalcitonin(PCT)is used as a biomarker of infection in the emergency department(ED),but its role in rhabdomyolysis(RM)following exertional heatstroke(EHS)remains unclear.METHODS:A retrospective cohort study enrolled patients with EHS from the intensive care unit(ICU).We collected RM biomarkers,inflammation markers,critical disease scores at admission,24 h,48 h,and discharge,and 90-day mortality.Correlation analysis,linear regression and curve fi tting were used to identify the relationship between PCT and RM.RESULTS:A total of 162 patients were recruited and divided into RM(n=56)and non-RM(n=106)groups.PCT was positively correlated with myoglobin(Mb),acute hepatic injury,disseminated intravascular coagulation(DIC),Sequential Organ Failure Assessment(SOFA)score,and Acute Physiology and Chronic Health Evaluation II(APACHE II)score,with correlation coefficients of 0.214,0.237,0.285,0.454,and 0.368,respectively(all P<0.05).Interestingly,the results of curve fi tting revealed a nonlinear relationship between PCT and RM,and a two-piecewise linear regression model showed that PCT was related to RM with an odds ratio of 1.3 and a cut-off of<4.6 ng/mL.Survival analysis revealed that RM was associated with higher mortality compared to non-RM cases(P=0.0093).CONCLUSION:High serum PCT concentrations are associated with RM after EHS in critically ill patients.Elevated PCT concentrations should be interpreted cautiously in patients with EHS in the ED.
文摘Background: The exRML (exertional rhabdomyolysis) is a pathophysiologic condition of skeletal muscle cell damage and breakdown associated with high intensity or prolonged exercise, normal exercise under extreme circumstances, or sudden and excessive skeletal muscle contraction. It may manifest from the increase in CK (creatine kinase) or MYO (myoglobin), a protein that can cause life-threatening injury to the kidney (AKI, acute kidney injury), and may or may not be associated with myoglobinuria. Here, we presented a case of exRML with AKI, and then reviewed the related reports. Vigorous hydration, sodium bicarbonate and furosemide are key treatments. Aim: To examine an elderly patient with exRML induced AKI and the key treatment process. Case summary: A 61-year-old man left our hospital without permission after his admission and has been walking for almost 30 kms with no water and food intake, then was diagnosed exRML and exRML induced AKI with an obvious elevation of CK, MYO and decrease of eGFR (estimated glomerular filtration rate) after coming back, and was treated with vigorous hydration, loop diuresis, sodium bicarbonate, prostaglandin and Shenkang injection. After vigorous resuscitation, the patient’s renal function, CK and MYO returned normal. Conclusions: The exRML can cause serious complications such as AKI and death. Delayed diagnosis can be critical;therefore, manner of time should be taken to achieve a favorable prognosis.
基金supported by the National Natural Science Foundation of China,NSFC(No.21101091)Hunan Provincial Natural Science Foundation(No.11JJ4017)+1 种基金Hunan Provincial Education Foundation(No.11B105)the initial foundation for oversea scholar return to University of South China(No.2011XQD16)
文摘By retaining the native distal His64 in sperm whale myoglobin （Mb）, a second distal histidine was engineered in Mb by mutating Leu29 to His29. The resultant mutant of L29H Mb exhibits an unusual enhanced peroxidase activity with a positive cooperativity in comparison to that of wild type Mb. The new enzyme with two cooperative distal histidines has not been found in native peroxidase, which emohasizes a creation of the rational nmt^in doclan
