Effect of resveratrol on pancreatic oxygen free radicals in rats with severe acute pancreatitis

AIM： To investigate the therapeutic effects of resveratrol （RESV） as a free radical scavenger on experimental severe acute pancreatitis （SAP）. METHODS： Seventy-two male Sprague-Dawley rats were divided randomly into sham operation group, SAP group, and resveratrol-treated group. Pancreatitis was induced by intraductal administration of 0.1 mL/kg 4% sodium taurocholate. RESV was given intravenously at a dose of 20 mg/kg body weight. All animals were killed at 3, 6, 12 h after induction of the model. Serum amylase, pancreatic superoxide dismutase （SOD）, malondialdehyde （MDA）, and myeloperoxidase （MPO） were determined. Pathologic changes of the pancreas were observed under optical microscope. RESULTS： The serum amylase, pancreatic MPO and the score of pathologic damage increased after the induction of pancreatitis, early （3, 6 h） SAP samples were characterized by decreased pancreatic SOD and increased pancreatic MDA. Resveratrol exhibited a protective effect against lipid peroxidation in cell membrane caused by oxygen free radicals in the early stage of SAP. This attenuation of the redox state impairment reduced cellular oxidative damage, as reflected by lower serum amylase, less severe pancreatic lesions, normal pancreatic MDA levels, as well as diminished neutrophil infiltration in pancreas. CONCLUSION： RESV may exert its therapeutic effect on SAP by lowering pancreatic oxidative free radicals and reducing pancreatic tissue infiltration of neutrophils.

Effects of ulinastatin combined with surgery on nerve injury, oxygen free radicals and inflammatory factors production of patients with hypertensive intracerebral hemorrhage

Objective: To study the effects of ulinastatin combined with surgery on nerve injury, oxygen free radicals and inflammatory factors production of patients with hypertensive intracerebral hemorrhage. Methods: The patients with hypertensive intracerebral hemorrhage received surgical treatment in our hospital during February 2015 - December 2017 were selected and divided into two groups by random number table. The observation group received ulinastatin combined surgery and the control group received conventional medicine combined with surgery. Before treatment and 1 weeks after treatment, serum levels of nerve damage markers, neurotrophic indexes, oxygen free radicals production indexes and inflammatory cytokines were measured. Results: After treatment, the contents of NSE, VILIP-1, GFAP, S100B, MDA, AOPP, 8-OHdG, NO, ET-1, TNF-α, sICAM-1, sVCAM-1, sICAM-1 of two groups were all decreased, the contents of BDNF, NGF, VEGF, IGF-I were all increased and the decreasing trend of NSE, VILIP-1, GFAP, S100B, MDA, AOPP, 8-OHdG, NO, ET-1, TNF-α, sICAM-1, sVCAM-1, sICAM-1 of observation group was more obvious than that of the control group, the increasing trend of BDNF, NGF, VEGF, IGF-I content was more obvious than that of the control group. Conclusion: The use of ulinastatin combined with surgery in the treatment of hypertensive intracerebral hemorrhage can significantly reduce the damage of nerve function and reduce the production of oxygen free radicals and inflammatory factors.

Effect of Selenium Poisoning on Immune Function and Oxygen Free Radicals in Erythrocyte of Pig

[ Objective] This study was to investigate the effect of selenium（Se） on immune function and oxygen free radicals in erythrocyte of pig. [ Method] Fifteen weanling Landrace piglets as experimental animals were divided into three groups, two testing groups and one control group. For each group, Se content in whole blood, immune function of erythrocytes, activity of whole blood glutathione peroxidase（GSH-Px）, activity of blood plasma superoxide dismutase（SOD）, and blood plasma malondialdehyde（MDA） content were determined. [ Result] Compared with the control group, Se content in whole blood and blood plasma MDA content increased remarkably, while whole blood GSH-Px activity and blood plasma SOD activity decreased; RBC-C1 RR assumed a rise-fall trend, and RBC-ICR showed no obvious change. [Condusion] Se poisoning can reduce the activity of antioxidant enzymes, disturb the balance of oxygen free radicals metabolism, thereby inducing erythrooyte immune function in piglets.

THE ACTION OF CAPTOPRIL ON SCAVENGING OXYGEN FREE RADICALS

The protective effect of captopril on ischemic myocardium was studied in 40 patients with congenital heart disease accompanied with pulmonary hypertention.Twenty of these patients received captopril 50 mg b.i.d.for three months preoperatively (Group A).The other 20 patients without pretreatment with captopril were used as controls (Group B).In Group A,the cardiac output increased and the pulmonary pressure decreased significantly in the first 24 hours postoperatively,indicating a high cardiac output with a low vascular resistance.The differences or CPK,CPKMB,LDH release between Group A and Group B were highly significant or siguificant from the end of operation to 24 hours postoperatively. Myocardial protection in the reduction of the release of CPK, CPK-MB, LDH might be attributed to action on scavenging oxygen free radicals.

Direct Measurement of Oxygen Free Radicals of the Liver Tissue Following Shock/Reperfusion and Its Significance

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The influence of ultraviolet blood irradiation and oxygenation on oxygen free radicals metabolism in rabbits with soman intoxication

Objective: To investigate the effect of ultraviolet blood irradiation and oxygenation (UBIO) on the metabolism of oxygen free radicals in rabbits with acute soman intoxication. Methods: One hundred rabbits were randomly divided into 5 groups: normal control group, intoxication group, routine therapy group. UBIO therapy group and combined therapy group. After 14 d, the concentration of malondiadehyde(MDA) and activity of superoxide dismutase(SOD), glutathionperoxidase(GSH-Px), catalase (CAT) and total antioxidative capacity (T-AOC) in serum were determined respectively. Results: Compared with the normal control group, the concentration of MDA and activity of CAT in the intoxication group were significantly higher (P < 0. 05). but SOD. GSH-Px activity and T-AOC were significantly lower (P<0. 05). After UBIO or combined therapy, serum MDA level was significantly lower in comparison with intoxication group (P<0. 05). but the activity of SOD. GSH-Px, CAT and T-AOC were higher than intoxication group(P<0. 05). Conclusion: There is an obvious oxygen free radical injury in rabbits with a-cute soman intoxication. UBIO can improve the antioxidation ability of rabbits and may be applied to treat acute soman intoxication as adjunctive therapy.

Effect of dexmedetomidine combined with ulinastatin on RAAS system,coagulation indexes and oxygen free radicals after acute aortic dissection surgery

Objective: To study the effect of dexmedetomidine combined with ulinastatin on RAAS system, coagulation indexes and oxygen free radicals after acute aortic dissection surgery. Methods: A total of 48 patients with aortic dissection who accepted endovascular graft exclusion treatment in the hospital between May 2014 and February 2017 were selected and randomly divided into two groups, group A received dexmedetomidine, ulinastatin combined with general anesthesia, and group B received general anesthesia. The RAAS hormones, coagulation indexes and oxygen free radical indexes were measured 1 d before surgery, during operation and 24 h after surgery. Results: During operation and after operation, serum REN, AT-II, ALD, FIB, DD, MDA and MPO contents as well as APTT and TT levels of both groups of patients were significantly higher than those before operation while TAOC and TSOD contents were significantly lower than those before operation, and serum REN, AT-II, ALD, FIB, DD, MDA and MPO contents as well as APTT and TT levels of group A were significantly lower than those of group B while TAOC and TSOD contents were significantly higher than those of group B. Conclusion: Dexmedetomidine combined with ulinastatin for acute aortic dissection can inhibit RAAS system and oxygen free radical generation and improve coagulation function.

Oxygen radical formation does not have an impact in the treatment of severe acute experimental pancreatitis using free cellular hemoglobin

AIM： Microcirculatory dysfunction and free oxygen radicals are important factors in the pathogenesis of severe acute pancreatitis. Additional oxygen delivery might enhance lipid peroxidation but may also improve pancreatic microcirculation. This study assesses the effect of free cellular bovine hemoglobin on the formation of oxygen radicals and microcirculation in a rodent model of severe acute pancreatitis. METHODS： Fifteen minutes after induction of acute pancreatitis Wistar rats received either 0.8 mL bovine hemoglobin （HBOC-200）, hydroxyethyl starch （HES） or 2.4 mL of normal saline to ensure normovolemic substitution. After 6 h of examination the pancreas was excised and rapidly processed for indirect measurement of lipid peroxidation products malondialdehyde （MDA） and reduced glutathione （GSH） in pancreatic tissue. RESULTS： The single application of HBOC-200 improved pancreatic microcirculation and reduced histopathological tissue damage significantly. Tissue concentration of MDA did not differ between the groups. Also no differences in GSH levels were detected.CONCLUSION： Though the single application of HBOC-200 and HES improve pancreatic microcirculation, no differences in lipid peroxidation products were detected. The beneficial effect of additional oxygen supply （HBOC-200） does not lead to enhanced lipid peroxidation.

The Collapse Intensity of Cavities and the Concentration of Free Hydroxyl Radical Released in Cavitation Flow

Enhancing the chemical reaction processes by means of the energy released in the collapse of micro bubbles or cavities in the cavitation flow is a new research area. In the previous work, a new approach of measuring concentration of free hydroxyl radicals induced in cavitation flow by using methylene blue as the indicator was developed and used to study concentration of free radical induced in Venturi cavitation flow under various experimental conditions. In the present research, the radial evolution of a cavity bubble and the corresponding collapse pressure in sonic cavitation field are obtained by solving three different bubble dynamics equations： Rayleigh equation, Rayleigh-Plesset equation and Gilmore equation. By comparing with the experimental data on the radial evolution of a cavity bubble in the literature, it is found that the predicted results by the Gilmore equation, which takes account of the compressibility of fluid in addition to the viscosity and interfacial tension, agree with the experimental ones better than those by other two equations. Moreover, the theoretically predicted collapse pressures are consistent with the concentration of the free hydroxyl radical induced in the experimental venture. Thus, the concentration of the liberated free hydroxyl radical not only influences the reaction rate but also is used as an available parameter for measuring collapse intensity of cavities.

Granulocyte colony-stimulating factor increases extracellular glutamic acid uptake and suppresses free radicals in an experimental model of amyotrophic lateral sclerosis

Excitatory amino acid toxicity and free radical damage play important roles in amyotrophic lateral sclerosis. Granulocyte colony-stimulating factor （G-CSF） protects nerve cells exposed to high-concentrations of glutamic acid, suggesting positive effects in the treatment of amyotrophic lateral sclerosis. The present study induced in vitro motor neuron injury using glutamic acid excitotoxicity, and the biochemical effects of G-CSF on glutamic acid concentration were determined. In addition, the effects of G-CSF on superoxide dismutase, glutathione peroxidase activity in motor neurons, and malondialdehyde and nitric oxide contents were analyzed. Immunohistochemistry was performed to measure neuronal survival. Results revealed that G-CSF significantly suppressed free radical activity, inhibited excitotoxicity, and reduced apoptosis and loss of motor neurons in the anterior horn of the spinal cord.

Election Spin Resonance Studies of Free Radical Formation and Oxygen Consumption of Lens Epithelium During Ultraviolet Exposure

A long life election spin resonance (ESR) signal at g=2.0006 was observed in the normal lens epithelium and cortical fibers. During ultraviolet (UV) exposure, a new ESR signal at g = 2.0060 was found in the lens epithelium. But this specific signal was not detected in the lens cortical fibers. This suggested that lens epithelial cells were more susceptible to the free radical formation which was induced by UV light. By means of ESR spin probe oxymetry, the oxygen uptake of lens epithelial cells was meas...

Correlation of oxygen free radical items between blood and kidney of chronic renal failure rat

The correlation of oxygen free radical items between blood and kidney of 5/6 nephrectomy-induced chronic renal failure rats was studied. It was found that oxygen free radicals played an important role in the impairment of remnant kidney,and antioxidant vitamin E could protect remnant kidney from the impairment caused by oxygen free radicals,and that,both in normal and chronic renal failure conditions,plasma lipid peroxides and vitamin E concentration and superoxide dismutase activity of red blood cells correlated very well with corresponding items of remnant kidney.These results suggested that blood oxygen free radical items could reflect renal oxygen free radical metabolic status in chronic renal failure patients.

EFFECT OF ACUPUNCTURE ON BLOOD OXYGEN FREE RADICAL AND NO LEVELS IN TREATMENT OF APOPLECTIC SEQUELAE

Objective: To observe the effect of acupuncture on blood oxygen free radical (OFR) and nitric oxide (NO) levels in the treatment of apoplectic sequelae. Methods: A total of 61 cases of apoplectic patients were subjected into this study and randomly divided into "JIN San Zhen" group (n=30) and control group (n=31). Blood lipid peroxidase (LPO), superoxide dismutase (SOD), glutathione peroxidase(GSH Px) and nitric oxide (NO) contents before and after acupuncture treatment were determined with radioimmunoassay. In both groups, acupuncture was given once daily, six times a week, with 4 weeks being a therapeutic course and with the interval between two weeks being a week, 3 courses all together. In "JIN San Zhen" group, acupoints of "JIN San Zhen" were used predominately, while in control group, scalp point Motor Sensory Area (MS 8) was used as the main point. Results: Self comparison showed that after 3 courses of treatment, in both groups, LPO and NO levels decreased significantly (P<0.05-0.01), SOD and GST Px values increased considerably (P<0.05-0.01). Comparison between two groups indicated that the effects of "JIN San Zhen" group are significantly superior to those of control group in raising blood SOD and GST Px levels (P<0.05-0.01) and in lowering blood NO content (P<0.01). Analysis on the correlation between the restoration of neural function and the changes of LPO, SOD and GST Px levels suggested that the effect of acupuncture in improving neural function may be related to changes of the aforementioned indexes. Conclusion: Acupuncture therapy can significantly lower blood LPO and NO levels and evidently raise blood SOD and GST Px levels in stroke patients.

Effect of early rehabilitation training on oxygen free radical generation and nerve injury in patients with cerebral hemorrhage

Objective: To study the effect of early rehabilitation training combined with edaravone on oxygen free radical generation and nerve injury in patients with cerebral hemorrhage. Methods: A total of 56 patients with acute cerebral hemorrhage who were treated in Zigong Third People's Hospital between July 2014 and March 2017 were selected and randomly divided into early rehabilitation group and routine rehabilitation group, the early rehabilitation group began the rehabilitation training 2 d after cerebral hemorrhage condition was stabilized, and routine rehabilitation group began the rehabilitation training 14 d after cerebral hemorrhage. Serum contents of oxygen free radicals, nerve injury markers and neurotrophic molecules were detected 28 d and 56 d after cerebral hemorrhage. Results: 28 d and 56 d after cerebral hemorrhage, serum MDA, AOPP, 8-OHdG, GFAP, NSE, Tf, Ft and S100B levels of early rehabilitation group were significantly lower than those of routine rehabilitation group while BDNF, NGF, NTF-α and IGF-I levels were significantly higher than those of routine rehabilitation group. Conclusion: Early rehabilitation training combined with edaravone for cerebral hemorrhage can inhibit the oxygen free radical generation, reduce the degree of nerve injury and improve the neurotrophic state.

Correlation of electrophysiological characteristics Tp-ec and Tp-e/QT with myocardial injury and oxygen free radical generation in patients with acute myocardial infarction

Objective: To study the correlation of electrophysiological characteristics Tp-ec and Tp-e/QT with myocardial injury and oxygen free radical generation in patients with acute myocardial infarction. Methods: Patients who were diagnosed with acute myocardial infarction in our hospital between March 2014 and March 2017 were selected as the AMI group, and healthy subjects who received physical examination were selected as the control group, electrocardiography was done to determine Tp-ec and Tp-e/QT, serum was collected to determine the levels of myocardial injury markers, oxygen free radical generation indexes and apoptosis indexes, and peripheral blood was collected to determine the expression of oxygen free radical generation indexes. Results: Tp-ec and Tp-e/QT of AMI group were significantly higher than those of control group, and serum CK-MB, cTnI, H-FABP, MDA, sTWEAK, sFas and sTRAIL contents as well as peripheral blood Nrf-2, NRE and HO-1 mRNA expression were significantly higher than those of control group and positively correlated with Tp-ec and Tp-e/QT. Conclusion: Electrophysiological characteristics Tp-ec and Tp-e/QT increase, and the transseptal dispersion of repolarization increases in patients with acute myocardial infarction, and they are closely related to myocardial injury and oxygen free radical generation.

Sonme Factors that Affect the Free Radical-scavenging Activity of Tea Extracts

Some factors that affect the free radical-scavenging activety of two tea extracts were studied in vitro. It was found that concentration of tea extract or heating tea extract or treating with activated carbon and diatomite all had obvious effect on the scavenging activety of green tea extract ,but heating or treating with diaomite had less effect on the scavenging activity of black tea extract. Ascorbic acid, for having synergic effect with tea extracts, could enhance the scavenging activity of tea extracts markedly, and the contrary was cupric ion. Reducing sugars such as fructose and glucose also had some syncrgic effect to tea extracts.

Do reactive oxygen species damage or protect the heart in ischemia and reperfusion?Analysis on experimental and clinical data

The role of reactive oxygen species(ROS)in ischemic and reperfusion(I/R)injury of the heart has been discussed for more than 40 years.It has been demonstrated that reperfusion triggers a multiple increase in free radical generation in the isolated heart.Antioxidants were found to have the ability to mitigate I/R injury of the heart.However,it is unclear whether their cardioprotective effect truly depends on the decrease of ROS levels in myocardial tissues.Since high doses and high concentrations of antioxidants were experimentally used,it is highly likely that the cardioprotective effect of antioxidants depends on their interaction not only with free radicals but also with other molecules.It has been demonstrated that the antioxidant N-2-mercaptopropionyl glycine or NDPH oxidase knockout abolished the cardioprotective effect of ischemic preconditioning.Consequently,there is evidence that ROS protect the heart against the I/R injury.

水凝胶紫外光固化建模仿真

利用COMSOL Multiphysics仿真软件对紫外光固化进行建模和仿真,探究了单体浓度、引发剂浓度和氧气浓度对紫外光固化反应速度的影响。仿真结果表明:随着单体浓度和引发剂浓度的增加,反应逐渐加快;而随着氧气浓度的增加,反应先加快而后减慢,即氧阻聚现象。通过PEGDA水凝胶紫外光固化实验验证了单体浓度与反应速度的关系。

Highly efficient catalytic scavenging of oxygen free radicals with graphene-encapsulated metal nanoshields

Normal levels of oxygen free radicals play an important role in cellular signal transduction, redox homeostasis, regulatory pathways, and metabolic processes. However, radiolysis of water induced by high-energy radiation can produce excessive amounts of exogenous oxygen free radicals, which cause severe oxidative damages to all cellular components, disrupt cellular structures and signaling pathways, and eventually lead to death. Herein, we show that hybrid nanoshields based on single-layer graphene encapsulating metal nanoparticles exhibit high catalytic activity in scavenging oxygen superoxide （·O2^-）, hydroxyl （·OH）, and hydroperoxyl （HO2·） free radicals via electron transfer between the single-layer graphene and the metal core, thus achieving biocatalytic scavenging both in vitro and in vivo. The levels of the superoxide enzyme, DNA, and reactive oxygen species measured in vivo dearly show that the nanoshields can efficiently eliminate harmful oxygen free radicals at the cellular level, both in organs and circulating blood. Moreover, the nanoshields lead to an increase in the overall survival rate of gamma ray-irradiated mice to up to 90%, showing the great potential of these systems as protective agents against ionizing radiation.

Direct detection of oxygen free radicals produced in the viscera of burned rats using electron paramagnetic resonance spectroscopy

To detect superoxide anion (O - 2 ) signals in the heart, liver, lung and kidney tissues after burns. Methods: Twenty four male rats were randomized into 4 groups. The rats of experimental groups were immersed in 100℃ water for 15 seconds and 25% third degree burn was created. Thoracotomy or laparotomy was performed at 5, 10, 15, 20 and 30 minutes after burn, and specimens of the heart, lung, liver kidney were obtained for burned rats. The specimens were then preserved in liqu id nitrogen for cryo preservation and detected immediately using EPR. Results: The signals of superoxide O radical appeared in the he art, lung, 1iver and kidney specimens 10 15 minutes after burn. Conclusions: There is a direct evidence of oxygen free radicals (OFRs) injury to viscera of burned rats between 10 15 minutes after burn.