During the storage of composite propellants, the migration of plasticizers and other unbonded additives at the interfaces of liner adhesives has garnered significant attention in understanding liner failure mechanisms...During the storage of composite propellants, the migration of plasticizers and other unbonded additives at the interfaces of liner adhesives has garnered significant attention in understanding liner failure mechanisms, aging processes, and safety performance. However, there is currently no non-destructive and quantitative detection method for migration of plasticizers in propellant liner. In this study, we developed a HTPB sensing liner by incorporating conductive fillers-namely carbon black(CB), carbon nanotubes(CNTs), and graphene nanoplatelets(GNP)-into the HTPB matrix. The synergistic interaction between CNTs and GNP facilitates the formation of a tunneling conductive network that imparts electrical conductivity to the HTPB liner. To elucidate the functional relationship between conductivity and nitroglycerin(NG) migration, we applied the HTPB sensing liner onto double base propellant surfaces and measured both the conductivity of the sensing layer and NG migration during a 71°C accelerated aging experiment. The results shows that when CNTs/GNP content reaches 3wt%, there is an exponential correlation between conductivity and NG migration with a fitting degree of 0.9652;the average response sensitivity of ΔR/R0 relative to NG migration is calculated as 41.69, with an average deviation of merely5.67% between NG migrations derived from conductivity fittings compared to those obtained via TGA testing results. Overall, this sensing liner exhibits excellent capabilities for detecting NG migration nondestructively and quantitatively while offering a novel approach for assessing interfacial component migrations as well as debonding defects in propellants-a promising avenue for future self-monitoring strategies regarding propellant integrity.展开更多
Objective:To compare the effects of adding rocuronium and nitroglycerin to ropivacaine in intravenous regional anesthesia(IVRA)on pain and hemodynamic parameters.Methods:This randomized controlled trial was done in 20...Objective:To compare the effects of adding rocuronium and nitroglycerin to ropivacaine in intravenous regional anesthesia(IVRA)on pain and hemodynamic parameters.Methods:This randomized controlled trial was done in 2023.Participants were 177 candidates for forearm operation surgery under IVRA selected from Valiasr Hospital,Arak,Iran.They were allocated by block randomization to three different groups,namely nitroglycerin group,rocuronium group and control group.Hemodynamic parameters were recorded before tourniquet application up to postoperative recovery time.Sensory block and motor block onset and duration and pain were also evaluated.The data analysis was carried out by IMB SPSS software 20.0.Results:177 Eligible patients were included in study,with 59 in each group.Time to sensory and motor block onset in the nitroglycerin group was significantly less than the other groups and the time of motor block in the rocuronium group was statistically higher than the control and the nitroglycerin groups(P<0.001).Seven participants in the nitroglycerin group experienced headache and three from the rocuronium group experienced dizziness.The side effects occurrence in the nitroglycerin group was more prevalent than in the control and rocuronium groups(P=0.009).Conclusions:Nitroglycerin significantly reduces the time to sensory and motor block onset,while rocuronium is more effective in prolonging the time of motor block.Although there is no difference between nitroglycerin and rocuronium respecting the pain score and opioid need administration,nitroglycerin is associated with a higher prevalence of medication side effects.Therefore,both nitroglycerin and rocuronium can be used as adjuvant for IVRA.The final choice relies on patients’conditions and anesthesiologists’judgment.展开更多
AIM:Тo examine the effects of nitroglycerine on portal vein haemodynamics and oxidative stress in patients with portal hypertension.METHODS:Thirty healthy controls and 39 patients with clinically verified portal hype...AIM:Тo examine the effects of nitroglycerine on portal vein haemodynamics and oxidative stress in patients with portal hypertension.METHODS:Thirty healthy controls and 39 patients with clinically verified portal hypertension and increasedvascular resistance participated in the study.Liver di-ameters,portal diameters and portal flow velocities were recorded using color flow imaging/pulsed Doppler detection.Cross-section area,portal flow and index of vascular resistance were calculated.In collected blood samples,superoxide anion radical (O 2-),hydrogen per-oxide (H 2 O 2),index of lipid peroxidation (measured as TBARS) and nitric oxide (NO) as a marker of endothelial response (measured as nitrite-NO 2-) were determined.Time-dependent analysis was performed at basal state and in 10th and 15th min after nitroglycerine (sublingual 0.5 mg) administration.RESULTS:Oxidative stress parameters changed sig-nificantly during the study.H 2 O 2 decreased at the end of study,probably via O 2-mediated disassembling in Haber Weiss and Fenton reaction;O 2-increased signifi-cantly probably due to increased diameter and tension and decreased shear rate level.Consequently O 2-and H 2 O 2 degradation products,like hydroxyl radical,initi-ated lipid peroxidation.Increased blood flow was to some extent lower in patients than in controls due to double paradoxes,flow velocity decreased,shear rate decreased significantly indicating non Newtonian char-acteristics of portal blood flow.CONCLUSION:This pilot study could be a starting point for further investigation and possible implemen-tation of some antioxidants in the treatment of portal hypertension.展开更多
To explore the effect of different positions and number of pyrrolidine bound to the carbon cage on the stabilization effect of fulleropyrrolidine derivatives to nitrocellulose(NC)/nitroglycerine(NG),we synthesized N-(...To explore the effect of different positions and number of pyrrolidine bound to the carbon cage on the stabilization effect of fulleropyrrolidine derivatives to nitrocellulose(NC)/nitroglycerine(NG),we synthesized N-(4-methoxy)phenylpyrrolidine-C_(60) and four different of bis(N-(4-methoxy)phenylpyrrolidine)-C_(60) compounds through Prato reaction.Their structures were characterized by UVevis,^(1)H NMR,^(13)C NMR,high-resolution mass spectroscopy,and single-crystal X-ray diffraction.Their stabilization effect to NC/NG were investigated using differential scanning calorimetry,methyl violet,vacuum stabilization effect,weight loss,and accelerating rate calorimeter tests.The results indicated these compounds had excellent stabilization effect to NC/NG.The stabilization effect of the fulleropyrrolidine bisadducts to NC/NG is significantly better than that of fulleropyrrolidine monoadduct and C_(60).Moreover,the position where pyrrolidine binds to fullerene in fulleropyrrolidine bisadducts is different,and its stabilization effect to NC is also different.The stabilization effect order of different bisadduct isomers to nitrocellulose is as follows:e-edge>trans-2>cis-2>trans-3.Electron paramagnetic resonance(EPR)and FT-IR were used to study the stabilization mechanism of fulleropyrrolidine derivatives to NC/NG.The EPR results also show that fulleropyrrolidine bisadducts with different addition sites have different abilities to absorb nitroxide,and their ability is better than that of the monoadduct and C_(60),which is consistent with the results of stabilization effect performance test.展开更多
The preventive effects of nitroglycerine （NG） on glucocorticoid-induced osteoporosis in growing rats were studied. Three-month-old female Wistar rats were randomly divided into control group （CON）, dexamethasone g...The preventive effects of nitroglycerine （NG） on glucocorticoid-induced osteoporosis in growing rats were studied. Three-month-old female Wistar rats were randomly divided into control group （CON）, dexamethasone group （DXM）, DXM plus a low dose NG group （NG-L）, DXM plus a middle dose NG group （NG-M） and DXM plus a high dose NG group （NG-H）, 8 rats in each group. The rat model of osteoporosis was developed by intramuscular injection of dexamethasone twice a week. NG 0.2, 0.4 and 1.0 mg/kg was administered by oral gavages to the treatment groups every day for 12 weeks. Rats in CON group and DXM group were treated with normal saline of the same amount. After the treatment, the bone mineral density （BMD） and bone metabolism-associated biochemical markers were determined. Compared with CON group, BMD of lumbar spine and femur in DXM group was decreased significantly （P〈0.05 and P〈0.01 respectively）, blood BGP levels and NO levels reduced （both P〈0.01）, and TRAP level increased （P〈0.05）. As compared with DXM group, BMD, serum BGP and NO were increased, and TRAP decreased in NG-L group and NG-M group, but had no significant difference in comparison to CON group. All the markers other than serum NO and TRAP levels had no significant difference between NG-H group and DXM group. It was concluded that low or middle doses of NG could prevent glucocorticoid-induced bone loss in growing rats, but high dose of NG could not. Supplement with NO donor could be considered as a preventive treatment for glucocorticoid-induced osteoporosis in a developing skeleton.展开更多
Objective To determine whether reduction in central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-load or is due to arterial dilation. Methods We compare...Objective To determine whether reduction in central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-load or is due to arterial dilation. Methods We compared effects of NTG with those of lower body negative pressure (LBNP). Hemodynamic measurements were made at rest,during LBNP (10,20 and 30 mmHg,each for 15 min) and after NTG (10,30 and 100 μg/min,each dose for 15 min) in ten healthy volunteers. Cardiac pre-load,stroke volume and cardiac output were assessed by echocardiography. Central pressure augmentation and central systolic pressure were obtained by radial tonometry using a transfer function. Results LBNP (20 mmHg) and NTG (30 μg/min) reduced pre-load (as measured by the peak velocity of the S wave in the superior vena cava) to a similar degree [by (26.8±3.8)% and (23.9±3.4)%,respectively]. Compared to LBNP,NTG reduced systemic vascular resistance [by (32.9±7.5)%,P<0.01],decreased peripheral and central pressure augmentation [by (20.8±3.4)% units and (12.9±2.9)% units,respectively,each P<0.01]. Conclusion These results suggest that a reduction in pre-load does not explain reduction in pressure augmentation and central systolic blood pressure by NTG and that these effects are mediated through arterial dilation.展开更多
Tolerance to nitroglycerin(GTN)greatly limits its long-time application,and the underlying mechanism remains largely unexplored.In the present study,we aimed to investigate the comprehensive changes in the transcripto...Tolerance to nitroglycerin(GTN)greatly limits its long-time application,and the underlying mechanism remains largely unexplored.In the present study,we aimed to investigate the comprehensive changes in the transcriptome of rat aorta tolerant to GTN by analyzing lncRNA expression.We employed the RNA sequencing(RNA-seq)technique to identify mRNAs and lncRNAs.Ingenuity pathway analysis(IPA)was used for pathway and functional analysis.RT-qPCR was used to validate the RNA-seq results.We identified 22788 genes(reads per kilobase million[RPKM]>0.1,14720 protein-coding genes and 4408 lncRNAs),including 115 differentially expressed(DE)mRNAs(65 up-regulated and 50 down-regulated)and 104 DE lncRNAs(56 up-regulated and 48 down-regulated),in GTN-tolerant aortas.IPA revealed the inhibition of a canonical pathway“Signaling by Rho Family GTPases”and alteration in six upstream regulators.Functional analysis showed that 11 genes were related to“disorder of blood pressure”.We predicted the cis-target genes of DE lncRNAs by the analysis of their neighboring genes.The results revealed the 28 DE lncRNAs adjacent to the 26 protein-coding genes.Many DE mRNAs and cis-target genes of DE lncRNAs have been implicated in the regulation of blood pressure or cell contraction.These results suggested that the dysregulated mRNAs and lncRNAs contributed to the development of GTN tolerance and could serve as potential targets to prevent and reverse GTN tolerance.展开更多
Although preterm birth is the delivery before 37 + 0 weeks of gestation, the majority of prema-turity-related complications occur before 33 + 0 weeks of gestation. The need of today is to select the best agent out of ...Although preterm birth is the delivery before 37 + 0 weeks of gestation, the majority of prema-turity-related complications occur before 33 + 0 weeks of gestation. The need of today is to select the best agent out of the broad spectrum of available tocolytic agents, for providing maximum benefit to unfortunate sufferers of prematurity. The study aims to assess the role of “Dermal Nitroglycerin Patch” in treatment of preterm labour. Method: Study conducted in Department of Obstetrics & Gynecology, NIMS Medical College & Hospital, Jaipur from July 2014-December 2014. A prospective randomized study of 50 women of preterm labor was enrolled after informed consent. Patients were given dermal nitroglycerin patch as tocolytic agent according to study protocol. Result: 1) Results of NTG PATCH are comparable with other tocolytic drugs in terms of successful tocolysis;2) Maternal and fetal outcome is favourable in cases of NTG PATCH USE in preterm labour;3) Side effect profile was also better with NTG Patch. Conclusion: This randomized prospective study lends support to the proportion that Transdermal Nitroglycerine (NTG Patch) may be promising safe, effective, well tolerated, cost effective and non invasive method of tocolysis.展开更多
Objective. To investigate whether angiotensin II receptor antagonist and endothelin receptor antagonist can improve the nitroglycerin (Nit) tolerance in vivo. Methods. Twenty- four rats were divided into 4 groups (n=6...Objective. To investigate whether angiotensin II receptor antagonist and endothelin receptor antagonist can improve the nitroglycerin (Nit) tolerance in vivo. Methods. Twenty- four rats were divided into 4 groups (n=6,each): Control group, Nitroglycerin (Nit) group, Nit＋ bosentan group and Nit＋ losartan group. Nitroglycerin tolerance was induced by 2- day treatment of nitroglycerin patch (0.05 mg/h). AngiotensinⅡ receptor antagonist losartan ( 10 mg· kg－ 1· d－ 1 ) and endothelin receptor antagonist bosentan ( 100 mg· kg－ 1· d－ 1 ) were given by gavage for 2 days respectively. Results. The least hypotensive response to sodium nitroprusside (SNP) was observed in Nit group . The effective percentages of hypotensive response to SNP were increased in both Nit＋ losartan group and Nit＋ bosentan group compared with Nit group [(31.95± 4.45 )％ vs (21.00± 3.69 )％ , P< 0.01 and (33.18± 6.16 )％ vs (21.00± 3.69 )％ , P< 0.01 ,respectively]. The maximal vessel relaxation induced by SNP was the same in 4 different groups but the highest EC50 (concentration which produces 50％ of the maximal response to SNP) was found in tolerant group[(34± 10) nmol/ L,P < 0.01 .The ET- 1 amounts in plasma and vascular tissue were markedly increased by 54％ and 60％ in Nit group compared with those in control group(P< 0.01).The ET- 1 amounts in plasma and vascular tissue were decreased by 30％ and 37％ in Nit＋ losartan group compared with those in Nit group (P< 0.01). Conclusion. Endothelin receptor antagonist and angiotensinⅡ receptor antagonist could prevent against the Nit tolerance .展开更多
Objective To observe the dynamic changes of the plasma ET 1 and the effect of low dose nitroglycerin in patients with coronary artery bypass surgery. Methods\ Forty patients with coronary artery bypass surgery wer...Objective To observe the dynamic changes of the plasma ET 1 and the effect of low dose nitroglycerin in patients with coronary artery bypass surgery. Methods\ Forty patients with coronary artery bypass surgery were divided into two group: A and B. Group B received intravenous nitroglycerin 1 μg·kg\+\{ 1\}·min\+\{ 1\} perioperatively. RIA was used to assay the plasma ET 1 level. All the hemodynamic parameters were recorded by the Swan Ganze catheter. Results\ The preoperative plasma ET 1 level in patients with coronary artery disease was significantly higher than the normal level. Five minutes after cardiopulmonary bypass in these patients the plasma ET 1 level was increased significantly until 6 to 8 h after operation. The increasing plasma ET 1 level in group B was less intense than that in group A. There was a positive correlation between the plasma ET 1 level and the mean pulmonary artery pressure in group A 2 and 8 h after operation. Conclusion\ In patients undergoing coronary artery bypass surgery, the increased plasma ET 1 level may be due to the influence of cardiopulmonary bypass partly. Low dose nitroglycerin is beneficial to these patients.展开更多
This work is investigating Mexidol (2-ethyl-6-methyl-3-hydroxy pyridine succinate) effect on the formation of nitric oxide (NO) in animal liver tissues, which is a regulator of many physiological processes and plays a...This work is investigating Mexidol (2-ethyl-6-methyl-3-hydroxy pyridine succinate) effect on the formation of nitric oxide (NO) in animal liver tissues, which is a regulator of many physiological processes and plays an important role in the vascular relaxation, neurotransmission and immune system functioning. Analyses performed by EPR spectroscopy revealed Hem-NO complex signals from paramagnetic centers in arbitrary units;produced nitrogen oxide amount in liver tissues was determined by method of double integration signals from nitrosyl complexes.展开更多
Objectives Nitroglycerine (NTG) enhances coronary blood flow to compromised myocardium is important in relieving ischemia. However, the mechanism for this increase in myocardial blood flow (MBF) is not well defined. I...Objectives Nitroglycerine (NTG) enhances coronary blood flow to compromised myocardium is important in relieving ischemia. However, the mechanism for this increase in myocardial blood flow (MBF) is not well defined. In small vessels and capillaries, relative blood viscosity plays a very important role in determining myocardial vascular resistance (MVR). MVR reduce is due partly to the increase in negative charge of erythrocyte surface. We therefore hypothesized that the enhancement of nutrient blood flow to zones of myocardial ischemia during NTG is partly secondary to reduced MVR and blood flow viscosity. The latter is affected by the negative charge of erythrocyte surface. Methods 6 dogs with LAD flow-limiting stenosis (group 1) and 6 dogs with LAD flow-limiting stenosis and LCx occmusion (group 2) were studied. At baseline and during intracoronary infusions of NTG (0.3-0.6 μg·kg-1·min-1), hemodynamics, MBF (mL·min-1·g-1), whole blood viscosity (WBη, mPa. S), elongation index (EI), eletrophoretic mobility of erythocytes (EME, [μ.s-1)/(V.cm-1)]) and percent wall thickening (%WT) were determined. MVR was calculated using driving pressure/MBF. Results As compared to baseline, no changes in hemodynamics were seen during NTG. MBF increased and MVR decreased significantly in normal bed, the central 25% and the entire of stenosed bed (P<0.05), with a decrease in WBη in both group 1 and group 2 dogs (18.6±9.7 % and 19.2±14.5 %, respectively). However, the % decrease in WBη was proportioned to the % increase in MBF or the % decrease in MVR only in the central 25% of stenosed bed (r=0.87, P<0.001), but not in the entire stenosed bed and normal bed. EI did not show statistically significant differences between during NTG and at baseline, but EME did increase. And the % decrease in WBη during NTG was related to the % increase in EME (r=0.83, P=0.01). Conclusions NTG reduced myocardial vascular resistance and blood viscosity due to the change of negative charge of erythrocyte surface may, in part, be the mechanism of the enhancement of nutrient blood flow to zones of myocardial ischemia. These results provide additional insights into the complex anti-ischemic effects of NTG.展开更多
Objective: to summarize the efficacy of Urapidil and Nitroglycerin in the treatment of hypertension. Methods: 86 patients with acute hypertension who received treatment in our hospital from April 2019 to September 202...Objective: to summarize the efficacy of Urapidil and Nitroglycerin in the treatment of hypertension. Methods: 86 patients with acute hypertension who received treatment in our hospital from April 2019 to September 2020 were selected as the research subjects. The conventional group was treated with Nitroglycerin. The experimental group was treated with Urapidil on the basis of the conventional group. A comparative study was conducted based on the effective rate of treatment and serum index. Results: the therapeutic effect of the experimental group was better than that of the conventional group, P < 0.05. The serum index of experimental group was better than those of conventional group (P < 0.05). Conclusion: nitroglycerin combined with Urapidil can be effectively applied in the pre-hospital care for hypertensive emergency. The curative effect is exact and the first-aid effect is better. It is worthy of popularization.展开更多
Objective: To study the effect and promotion value of nitroglycerin combined with metoprolol in the treatment of chronic heart failure. Methods: the time span of this study was from August 2018 to August 2019. 120 pat...Objective: To study the effect and promotion value of nitroglycerin combined with metoprolol in the treatment of chronic heart failure. Methods: the time span of this study was from August 2018 to August 2019. 120 patients who met the inclusion criteria were selected and divided into two groups in accordance with the random number table. There were 60 patients in each group. Patients in the control group were treated with nitroglycerin alone, while patients in the observation group were treated with nitroglycerin combined with metoprolol. Analyze the clinical effect of the combined treatment by comparing the disease control state of the two groups of patients after treatment. Results: after the treatment course, the disease control effect of the two groups was evaluated, in terms of the total effective rate, patients in the observation group achieved better results, significantly higher than those in the control group, the difference between the two groups was statistically significant (P < 0.05). Conclusion: nitroglycerin combined with metoprolol in the treatment of patients with chronic heart failure can achieve therapeutic effect better. The patient's symptoms were significantly improved. So nitroglycerin combined with metoprolol can be widely used in clinical treatment.展开更多
基金funded by Zhijian Laboratory Open Fund,Rocket Force University of Engineering(Grant No.2023-ZJSYS-KF01-03).
文摘During the storage of composite propellants, the migration of plasticizers and other unbonded additives at the interfaces of liner adhesives has garnered significant attention in understanding liner failure mechanisms, aging processes, and safety performance. However, there is currently no non-destructive and quantitative detection method for migration of plasticizers in propellant liner. In this study, we developed a HTPB sensing liner by incorporating conductive fillers-namely carbon black(CB), carbon nanotubes(CNTs), and graphene nanoplatelets(GNP)-into the HTPB matrix. The synergistic interaction between CNTs and GNP facilitates the formation of a tunneling conductive network that imparts electrical conductivity to the HTPB liner. To elucidate the functional relationship between conductivity and nitroglycerin(NG) migration, we applied the HTPB sensing liner onto double base propellant surfaces and measured both the conductivity of the sensing layer and NG migration during a 71°C accelerated aging experiment. The results shows that when CNTs/GNP content reaches 3wt%, there is an exponential correlation between conductivity and NG migration with a fitting degree of 0.9652;the average response sensitivity of ΔR/R0 relative to NG migration is calculated as 41.69, with an average deviation of merely5.67% between NG migrations derived from conductivity fittings compared to those obtained via TGA testing results. Overall, this sensing liner exhibits excellent capabilities for detecting NG migration nondestructively and quantitatively while offering a novel approach for assessing interfacial component migrations as well as debonding defects in propellants-a promising avenue for future self-monitoring strategies regarding propellant integrity.
基金approved by the Ethics Committee of Arak University of Medical Sciences,Arak,Iran(No.IR.ARAKMU.REC.1402.033)registered in the Iranian Registry of Clinical Trials(No.IRCT20141209020258N183).
文摘Objective:To compare the effects of adding rocuronium and nitroglycerin to ropivacaine in intravenous regional anesthesia(IVRA)on pain and hemodynamic parameters.Methods:This randomized controlled trial was done in 2023.Participants were 177 candidates for forearm operation surgery under IVRA selected from Valiasr Hospital,Arak,Iran.They were allocated by block randomization to three different groups,namely nitroglycerin group,rocuronium group and control group.Hemodynamic parameters were recorded before tourniquet application up to postoperative recovery time.Sensory block and motor block onset and duration and pain were also evaluated.The data analysis was carried out by IMB SPSS software 20.0.Results:177 Eligible patients were included in study,with 59 in each group.Time to sensory and motor block onset in the nitroglycerin group was significantly less than the other groups and the time of motor block in the rocuronium group was statistically higher than the control and the nitroglycerin groups(P<0.001).Seven participants in the nitroglycerin group experienced headache and three from the rocuronium group experienced dizziness.The side effects occurrence in the nitroglycerin group was more prevalent than in the control and rocuronium groups(P=0.009).Conclusions:Nitroglycerin significantly reduces the time to sensory and motor block onset,while rocuronium is more effective in prolonging the time of motor block.Although there is no difference between nitroglycerin and rocuronium respecting the pain score and opioid need administration,nitroglycerin is associated with a higher prevalence of medication side effects.Therefore,both nitroglycerin and rocuronium can be used as adjuvant for IVRA.The final choice relies on patients’conditions and anesthesiologists’judgment.
基金Supported by The Grant from the Ministry of Science and Technical Development of the Republic of Serbia,No.175043
文摘AIM:Тo examine the effects of nitroglycerine on portal vein haemodynamics and oxidative stress in patients with portal hypertension.METHODS:Thirty healthy controls and 39 patients with clinically verified portal hypertension and increasedvascular resistance participated in the study.Liver di-ameters,portal diameters and portal flow velocities were recorded using color flow imaging/pulsed Doppler detection.Cross-section area,portal flow and index of vascular resistance were calculated.In collected blood samples,superoxide anion radical (O 2-),hydrogen per-oxide (H 2 O 2),index of lipid peroxidation (measured as TBARS) and nitric oxide (NO) as a marker of endothelial response (measured as nitrite-NO 2-) were determined.Time-dependent analysis was performed at basal state and in 10th and 15th min after nitroglycerine (sublingual 0.5 mg) administration.RESULTS:Oxidative stress parameters changed sig-nificantly during the study.H 2 O 2 decreased at the end of study,probably via O 2-mediated disassembling in Haber Weiss and Fenton reaction;O 2-increased signifi-cantly probably due to increased diameter and tension and decreased shear rate level.Consequently O 2-and H 2 O 2 degradation products,like hydroxyl radical,initi-ated lipid peroxidation.Increased blood flow was to some extent lower in patients than in controls due to double paradoxes,flow velocity decreased,shear rate decreased significantly indicating non Newtonian char-acteristics of portal blood flow.CONCLUSION:This pilot study could be a starting point for further investigation and possible implemen-tation of some antioxidants in the treatment of portal hypertension.
基金This work was supported by National Natural Science Foundation of China(51972278)Outstanding Youth Science and Technology Talents Program of Sichuan(no.19JCQN0085)Open Project of State Key Laboratory of Environment-friendly Energy Materials,Southwest University of Science and Technology(No.19fksy04).
文摘To explore the effect of different positions and number of pyrrolidine bound to the carbon cage on the stabilization effect of fulleropyrrolidine derivatives to nitrocellulose(NC)/nitroglycerine(NG),we synthesized N-(4-methoxy)phenylpyrrolidine-C_(60) and four different of bis(N-(4-methoxy)phenylpyrrolidine)-C_(60) compounds through Prato reaction.Their structures were characterized by UVevis,^(1)H NMR,^(13)C NMR,high-resolution mass spectroscopy,and single-crystal X-ray diffraction.Their stabilization effect to NC/NG were investigated using differential scanning calorimetry,methyl violet,vacuum stabilization effect,weight loss,and accelerating rate calorimeter tests.The results indicated these compounds had excellent stabilization effect to NC/NG.The stabilization effect of the fulleropyrrolidine bisadducts to NC/NG is significantly better than that of fulleropyrrolidine monoadduct and C_(60).Moreover,the position where pyrrolidine binds to fullerene in fulleropyrrolidine bisadducts is different,and its stabilization effect to NC is also different.The stabilization effect order of different bisadduct isomers to nitrocellulose is as follows:e-edge>trans-2>cis-2>trans-3.Electron paramagnetic resonance(EPR)and FT-IR were used to study the stabilization mechanism of fulleropyrrolidine derivatives to NC/NG.The EPR results also show that fulleropyrrolidine bisadducts with different addition sites have different abilities to absorb nitroxide,and their ability is better than that of the monoadduct and C_(60),which is consistent with the results of stabilization effect performance test.
文摘The preventive effects of nitroglycerine （NG） on glucocorticoid-induced osteoporosis in growing rats were studied. Three-month-old female Wistar rats were randomly divided into control group （CON）, dexamethasone group （DXM）, DXM plus a low dose NG group （NG-L）, DXM plus a middle dose NG group （NG-M） and DXM plus a high dose NG group （NG-H）, 8 rats in each group. The rat model of osteoporosis was developed by intramuscular injection of dexamethasone twice a week. NG 0.2, 0.4 and 1.0 mg/kg was administered by oral gavages to the treatment groups every day for 12 weeks. Rats in CON group and DXM group were treated with normal saline of the same amount. After the treatment, the bone mineral density （BMD） and bone metabolism-associated biochemical markers were determined. Compared with CON group, BMD of lumbar spine and femur in DXM group was decreased significantly （P〈0.05 and P〈0.01 respectively）, blood BGP levels and NO levels reduced （both P〈0.01）, and TRAP level increased （P〈0.05）. As compared with DXM group, BMD, serum BGP and NO were increased, and TRAP decreased in NG-L group and NG-M group, but had no significant difference in comparison to CON group. All the markers other than serum NO and TRAP levels had no significant difference between NG-H group and DXM group. It was concluded that low or middle doses of NG could prevent glucocorticoid-induced bone loss in growing rats, but high dose of NG could not. Supplement with NO donor could be considered as a preventive treatment for glucocorticoid-induced osteoporosis in a developing skeleton.
文摘Objective To determine whether reduction in central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-load or is due to arterial dilation. Methods We compared effects of NTG with those of lower body negative pressure (LBNP). Hemodynamic measurements were made at rest,during LBNP (10,20 and 30 mmHg,each for 15 min) and after NTG (10,30 and 100 μg/min,each dose for 15 min) in ten healthy volunteers. Cardiac pre-load,stroke volume and cardiac output were assessed by echocardiography. Central pressure augmentation and central systolic pressure were obtained by radial tonometry using a transfer function. Results LBNP (20 mmHg) and NTG (30 μg/min) reduced pre-load (as measured by the peak velocity of the S wave in the superior vena cava) to a similar degree [by (26.8±3.8)% and (23.9±3.4)%,respectively]. Compared to LBNP,NTG reduced systemic vascular resistance [by (32.9±7.5)%,P<0.01],decreased peripheral and central pressure augmentation [by (20.8±3.4)% units and (12.9±2.9)% units,respectively,each P<0.01]. Conclusion These results suggest that a reduction in pre-load does not explain reduction in pressure augmentation and central systolic blood pressure by NTG and that these effects are mediated through arterial dilation.
基金Scientific Research Fund of Hunan Provincial Education Department(Grant No.17B188,18A490)。
文摘Tolerance to nitroglycerin(GTN)greatly limits its long-time application,and the underlying mechanism remains largely unexplored.In the present study,we aimed to investigate the comprehensive changes in the transcriptome of rat aorta tolerant to GTN by analyzing lncRNA expression.We employed the RNA sequencing(RNA-seq)technique to identify mRNAs and lncRNAs.Ingenuity pathway analysis(IPA)was used for pathway and functional analysis.RT-qPCR was used to validate the RNA-seq results.We identified 22788 genes(reads per kilobase million[RPKM]>0.1,14720 protein-coding genes and 4408 lncRNAs),including 115 differentially expressed(DE)mRNAs(65 up-regulated and 50 down-regulated)and 104 DE lncRNAs(56 up-regulated and 48 down-regulated),in GTN-tolerant aortas.IPA revealed the inhibition of a canonical pathway“Signaling by Rho Family GTPases”and alteration in six upstream regulators.Functional analysis showed that 11 genes were related to“disorder of blood pressure”.We predicted the cis-target genes of DE lncRNAs by the analysis of their neighboring genes.The results revealed the 28 DE lncRNAs adjacent to the 26 protein-coding genes.Many DE mRNAs and cis-target genes of DE lncRNAs have been implicated in the regulation of blood pressure or cell contraction.These results suggested that the dysregulated mRNAs and lncRNAs contributed to the development of GTN tolerance and could serve as potential targets to prevent and reverse GTN tolerance.
文摘Although preterm birth is the delivery before 37 + 0 weeks of gestation, the majority of prema-turity-related complications occur before 33 + 0 weeks of gestation. The need of today is to select the best agent out of the broad spectrum of available tocolytic agents, for providing maximum benefit to unfortunate sufferers of prematurity. The study aims to assess the role of “Dermal Nitroglycerin Patch” in treatment of preterm labour. Method: Study conducted in Department of Obstetrics & Gynecology, NIMS Medical College & Hospital, Jaipur from July 2014-December 2014. A prospective randomized study of 50 women of preterm labor was enrolled after informed consent. Patients were given dermal nitroglycerin patch as tocolytic agent according to study protocol. Result: 1) Results of NTG PATCH are comparable with other tocolytic drugs in terms of successful tocolysis;2) Maternal and fetal outcome is favourable in cases of NTG PATCH USE in preterm labour;3) Side effect profile was also better with NTG Patch. Conclusion: This randomized prospective study lends support to the proportion that Transdermal Nitroglycerine (NTG Patch) may be promising safe, effective, well tolerated, cost effective and non invasive method of tocolysis.
文摘Objective. To investigate whether angiotensin II receptor antagonist and endothelin receptor antagonist can improve the nitroglycerin (Nit) tolerance in vivo. Methods. Twenty- four rats were divided into 4 groups (n=6,each): Control group, Nitroglycerin (Nit) group, Nit＋ bosentan group and Nit＋ losartan group. Nitroglycerin tolerance was induced by 2- day treatment of nitroglycerin patch (0.05 mg/h). AngiotensinⅡ receptor antagonist losartan ( 10 mg· kg－ 1· d－ 1 ) and endothelin receptor antagonist bosentan ( 100 mg· kg－ 1· d－ 1 ) were given by gavage for 2 days respectively. Results. The least hypotensive response to sodium nitroprusside (SNP) was observed in Nit group . The effective percentages of hypotensive response to SNP were increased in both Nit＋ losartan group and Nit＋ bosentan group compared with Nit group [(31.95± 4.45 )％ vs (21.00± 3.69 )％ , P< 0.01 and (33.18± 6.16 )％ vs (21.00± 3.69 )％ , P< 0.01 ,respectively]. The maximal vessel relaxation induced by SNP was the same in 4 different groups but the highest EC50 (concentration which produces 50％ of the maximal response to SNP) was found in tolerant group[(34± 10) nmol/ L,P < 0.01 .The ET- 1 amounts in plasma and vascular tissue were markedly increased by 54％ and 60％ in Nit group compared with those in control group(P< 0.01).The ET- 1 amounts in plasma and vascular tissue were decreased by 30％ and 37％ in Nit＋ losartan group compared with those in Nit group (P< 0.01). Conclusion. Endothelin receptor antagonist and angiotensinⅡ receptor antagonist could prevent against the Nit tolerance .
文摘Objective To observe the dynamic changes of the plasma ET 1 and the effect of low dose nitroglycerin in patients with coronary artery bypass surgery. Methods\ Forty patients with coronary artery bypass surgery were divided into two group: A and B. Group B received intravenous nitroglycerin 1 μg·kg\+\{ 1\}·min\+\{ 1\} perioperatively. RIA was used to assay the plasma ET 1 level. All the hemodynamic parameters were recorded by the Swan Ganze catheter. Results\ The preoperative plasma ET 1 level in patients with coronary artery disease was significantly higher than the normal level. Five minutes after cardiopulmonary bypass in these patients the plasma ET 1 level was increased significantly until 6 to 8 h after operation. The increasing plasma ET 1 level in group B was less intense than that in group A. There was a positive correlation between the plasma ET 1 level and the mean pulmonary artery pressure in group A 2 and 8 h after operation. Conclusion\ In patients undergoing coronary artery bypass surgery, the increased plasma ET 1 level may be due to the influence of cardiopulmonary bypass partly. Low dose nitroglycerin is beneficial to these patients.
文摘This work is investigating Mexidol (2-ethyl-6-methyl-3-hydroxy pyridine succinate) effect on the formation of nitric oxide (NO) in animal liver tissues, which is a regulator of many physiological processes and plays an important role in the vascular relaxation, neurotransmission and immune system functioning. Analyses performed by EPR spectroscopy revealed Hem-NO complex signals from paramagnetic centers in arbitrary units;produced nitrogen oxide amount in liver tissues was determined by method of double integration signals from nitrosyl complexes.
文摘Objectives Nitroglycerine (NTG) enhances coronary blood flow to compromised myocardium is important in relieving ischemia. However, the mechanism for this increase in myocardial blood flow (MBF) is not well defined. In small vessels and capillaries, relative blood viscosity plays a very important role in determining myocardial vascular resistance (MVR). MVR reduce is due partly to the increase in negative charge of erythrocyte surface. We therefore hypothesized that the enhancement of nutrient blood flow to zones of myocardial ischemia during NTG is partly secondary to reduced MVR and blood flow viscosity. The latter is affected by the negative charge of erythrocyte surface. Methods 6 dogs with LAD flow-limiting stenosis (group 1) and 6 dogs with LAD flow-limiting stenosis and LCx occmusion (group 2) were studied. At baseline and during intracoronary infusions of NTG (0.3-0.6 μg·kg-1·min-1), hemodynamics, MBF (mL·min-1·g-1), whole blood viscosity (WBη, mPa. S), elongation index (EI), eletrophoretic mobility of erythocytes (EME, [μ.s-1)/(V.cm-1)]) and percent wall thickening (%WT) were determined. MVR was calculated using driving pressure/MBF. Results As compared to baseline, no changes in hemodynamics were seen during NTG. MBF increased and MVR decreased significantly in normal bed, the central 25% and the entire of stenosed bed (P<0.05), with a decrease in WBη in both group 1 and group 2 dogs (18.6±9.7 % and 19.2±14.5 %, respectively). However, the % decrease in WBη was proportioned to the % increase in MBF or the % decrease in MVR only in the central 25% of stenosed bed (r=0.87, P<0.001), but not in the entire stenosed bed and normal bed. EI did not show statistically significant differences between during NTG and at baseline, but EME did increase. And the % decrease in WBη during NTG was related to the % increase in EME (r=0.83, P=0.01). Conclusions NTG reduced myocardial vascular resistance and blood viscosity due to the change of negative charge of erythrocyte surface may, in part, be the mechanism of the enhancement of nutrient blood flow to zones of myocardial ischemia. These results provide additional insights into the complex anti-ischemic effects of NTG.
文摘Objective: to summarize the efficacy of Urapidil and Nitroglycerin in the treatment of hypertension. Methods: 86 patients with acute hypertension who received treatment in our hospital from April 2019 to September 2020 were selected as the research subjects. The conventional group was treated with Nitroglycerin. The experimental group was treated with Urapidil on the basis of the conventional group. A comparative study was conducted based on the effective rate of treatment and serum index. Results: the therapeutic effect of the experimental group was better than that of the conventional group, P < 0.05. The serum index of experimental group was better than those of conventional group (P < 0.05). Conclusion: nitroglycerin combined with Urapidil can be effectively applied in the pre-hospital care for hypertensive emergency. The curative effect is exact and the first-aid effect is better. It is worthy of popularization.
文摘Objective: To study the effect and promotion value of nitroglycerin combined with metoprolol in the treatment of chronic heart failure. Methods: the time span of this study was from August 2018 to August 2019. 120 patients who met the inclusion criteria were selected and divided into two groups in accordance with the random number table. There were 60 patients in each group. Patients in the control group were treated with nitroglycerin alone, while patients in the observation group were treated with nitroglycerin combined with metoprolol. Analyze the clinical effect of the combined treatment by comparing the disease control state of the two groups of patients after treatment. Results: after the treatment course, the disease control effect of the two groups was evaluated, in terms of the total effective rate, patients in the observation group achieved better results, significantly higher than those in the control group, the difference between the two groups was statistically significant (P < 0.05). Conclusion: nitroglycerin combined with metoprolol in the treatment of patients with chronic heart failure can achieve therapeutic effect better. The patient's symptoms were significantly improved. So nitroglycerin combined with metoprolol can be widely used in clinical treatment.
