In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjian...In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjiang Province, China, and were randomly devided into 4 groups with 5 for each. ① supplemented with 0.7 mg·kg -1 iodine(potassium iodine), ② supplemented with 0.2 mg·kg -1 selenium (sodium selenite), ③ supplemented with 0.7 mg·kg -1 iodine(potassium Iodine) plus 0.2 mg·kg -1 selenium (sodium selenite) per day for 30 days, respectively. ④control group. The whole blood glutathione peroxidase (GSH-px) and catalase (CAT) activities, free radicals (FR) concentration, erythrocyte superoxide dismutase (SOD) activity and molonaldehyde (MDA) concentration, the serum triiodothyronine (T 3)、thyroxine (T 4) and thyrotropin (TSH) were determined on the day of supplementation day-0 and day-30, respectively. It was showed that average iodine concentration in drinking water and diet were 3.82 μg·L -1 and 0.285mg·kg -1 , respectively, Diet selenium was 0.0498mg·kg -1 , Serum protein bound iodine(PBI) was 7.02 μg·100 mL, Blood selenium was 0.14 mg·L -1 , the schoolchildren′s goiter was 21.8%. It indicated that iodine and selenium were deficient in the investigated area. Whole blood GSH-px and CAT activities and serum T 3 concentration were significantly higher (P< 0.01 ), FR concentration and serum TSH were significantly lower(P<0.01) in the first three groups than that of the control, T 4 content in the first group was higher(P<0.05), T 4 was also higher (P>0.05) in the second group. and lower in the third group. The SOD and MDA in erythrocyte were not changed during the experimental period, The results also showed that GSH-px and CAT activities were increased, and FR decreased oberviously in the third group more than the other two groups, In addition, Thyroid hormone metabolism was more coincided with the physiologic status in the third group. the iodine and the selenium played an important role in the pathologic process of free radical metabolic disorder. selenium not only had the function of antioxidation by derectly scavenging free radicals, but also affected through GSH-px and CAT activities. iodine deficiency results in the Goiter, selenium deficiency aggravated iodine deficiency, Iodine and the selenium were dependent and restrained each other in the course of free radicals and thyroid hormone metabolism with a synergistic state.展开更多
BACKGROUND: It has shown that magnetic field can improve blood circulation, decrease blood viscosity, inhibit free radicals, affect Ca2+ flow in nerve cells, control inflammatory and immunological reaction, and accele...BACKGROUND: It has shown that magnetic field can improve blood circulation, decrease blood viscosity, inhibit free radicals, affect Ca2+ flow in nerve cells, control inflammatory and immunological reaction, and accelerate nerve cell regeneration. In addition, protective effect of magnetic field, which acts as an iatrophysics, on ischemic brain tissues has been understood gradually. OBJECTIVE: To investigate the effects of rotating magnetic field (RMF) on volume of cerebral infarction, cerebral edema and metabolism of free radicals in rats after cerebral ischemia/reperfusion injury. DESIGN: Randomized controlled animal study. SETTING: Rehabilitation Center of disabled children, Liaoniang; Department of Rehabilitation, the Second Affiliated Hospital, China Medical University; Department of Rehabilitation Physiotherapy, the First Affiliated Hospital, China Medical University. MATERIALS: A total of 70 healthy Wistar rats aged 18-20 weeks of both genders were selected and randomly divided into 3 groups: sham operation group with 12 rats, control group with 20 rats and treatment group with 38 rats. The treatment group included 4 time points: immediate reperfusion with 6 ones, 6-hour reperfusion with 20 ones, 12-hour reperfusion with 6 ones and 18-hour reperfusion with 6 rats. Main instruments were detailed as follows: magnetic head of rotating magnetic device was 6 cm in diameter; magnetic induction intensity at the surface of magnetic head was 0.25 T in silence; the maximal magnetic induction intensity was 0.09 T at the phase of rotation; the average rotating speed was 2500 r per minute. METHODS: The experiment was carried out in the China Medical University in March 2003. Focal cerebral ischemic animal models were established with modified Longa’s method. Operation was the same in the sham operation, but the thread was inserted as 10 mm. Neurologic impairment was assessed with 5-rating method to screen out cases. Those survivals with grade 1 and grade 2 after ischemia for 2 hours and reperfusion for 24 hours were included in the control group and treatment group. Those in the sham operation group and control group were not treated with RMF. Magnetic head was directed towards the head of rats of the treatment group, and the magnetic head was about 7 mm from skin, treated for 15 minutes. The rats were decapitated to take out brains at 24 hours after reperfusion in each group. Water content of brain and volume of cerebral infarction were assessed with wet-dry weight method and TTC staining, respectively. Activity of superoxide dismutase (SOD), content of malondialdehyde (MDA) and change of brain histomorphology in brain tissue of ischemic side were analyzed. MAIN OUTCOME MEASURES: ① Volume of cerebral infarction and changes of water content in brain; ② measurements of SOD and MDA contents in brain tissue of rats in all groups. RESULTS: A total of 70 qualified animals were involved in the final analysis after rejecting the death and unqualified animal models. ① Water content of brain: Water content of brain in the treatment was less than that in the control group at any time point except the immediate time point, and cerebral edema was relieved [(2.48±0.22)%, (2.32±0.19)%, (2.23±0.36)%, (2.91±0.44)%, P < 0.05]. In addition, there were no significant differences among 6-hour, 12-hour and 18-hour reperfusion groups (P > 0.05). ② Volume of cerebral infarction: The absolute volume of cerebral infarction in the treatment group was smaller than that in the control group [(128.21±15.05), (171.22±40.50) mm3, t =2.438, P < 0.05], and the relative volume of cerebral infarction was smaller than that in the control group [(20.22±1.44)%, (25.17±3.85)%, t =2.95, P < 0.05]. ③ Contents of SOD and MDA in brain tissues: Compared with the control group, the SOD content in the brain tissue in the treatment group increased [(54.54±3.85), (69.52±5.88) kNU/g, t =5.568, P < 0.05], while the MDA content decreased [(0.85±0.06), (1.03±0.09) μmol/g, t =4.076, P < 0.05]. ④ General morphological observation: General morphology manifested that the edema was distinct in the right cerebral hemisphere in the control group, showing fat-like white, shallow anfractuosity, flat gyria, brittle tissue and easy to break up. The edema of right cerebral hemisphere was light and surface was hyperaemia in the treatment group. CONCLUSION: RMF may improve anti-oxidative ability of brain tissue of rats with acute focal cerebral ischemia/reperfusion injury and reduce volume of cerebral infarction and degrees of cerebral edema.展开更多
文摘In order to interpret pathologic mechanism of free radicals and thyroid hormone metabolism in cattle iodine and selenium deficiency, 20 heads of yellow cattle were selected from NiuJia town, Wu Chang City, Heilongjiang Province, China, and were randomly devided into 4 groups with 5 for each. ① supplemented with 0.7 mg·kg -1 iodine(potassium iodine), ② supplemented with 0.2 mg·kg -1 selenium (sodium selenite), ③ supplemented with 0.7 mg·kg -1 iodine(potassium Iodine) plus 0.2 mg·kg -1 selenium (sodium selenite) per day for 30 days, respectively. ④control group. The whole blood glutathione peroxidase (GSH-px) and catalase (CAT) activities, free radicals (FR) concentration, erythrocyte superoxide dismutase (SOD) activity and molonaldehyde (MDA) concentration, the serum triiodothyronine (T 3)、thyroxine (T 4) and thyrotropin (TSH) were determined on the day of supplementation day-0 and day-30, respectively. It was showed that average iodine concentration in drinking water and diet were 3.82 μg·L -1 and 0.285mg·kg -1 , respectively, Diet selenium was 0.0498mg·kg -1 , Serum protein bound iodine(PBI) was 7.02 μg·100 mL, Blood selenium was 0.14 mg·L -1 , the schoolchildren′s goiter was 21.8%. It indicated that iodine and selenium were deficient in the investigated area. Whole blood GSH-px and CAT activities and serum T 3 concentration were significantly higher (P< 0.01 ), FR concentration and serum TSH were significantly lower(P<0.01) in the first three groups than that of the control, T 4 content in the first group was higher(P<0.05), T 4 was also higher (P>0.05) in the second group. and lower in the third group. The SOD and MDA in erythrocyte were not changed during the experimental period, The results also showed that GSH-px and CAT activities were increased, and FR decreased oberviously in the third group more than the other two groups, In addition, Thyroid hormone metabolism was more coincided with the physiologic status in the third group. the iodine and the selenium played an important role in the pathologic process of free radical metabolic disorder. selenium not only had the function of antioxidation by derectly scavenging free radicals, but also affected through GSH-px and CAT activities. iodine deficiency results in the Goiter, selenium deficiency aggravated iodine deficiency, Iodine and the selenium were dependent and restrained each other in the course of free radicals and thyroid hormone metabolism with a synergistic state.
基金the Social Development Foundation Program of Liaoning Province,No.99225003
文摘BACKGROUND: It has shown that magnetic field can improve blood circulation, decrease blood viscosity, inhibit free radicals, affect Ca2+ flow in nerve cells, control inflammatory and immunological reaction, and accelerate nerve cell regeneration. In addition, protective effect of magnetic field, which acts as an iatrophysics, on ischemic brain tissues has been understood gradually. OBJECTIVE: To investigate the effects of rotating magnetic field (RMF) on volume of cerebral infarction, cerebral edema and metabolism of free radicals in rats after cerebral ischemia/reperfusion injury. DESIGN: Randomized controlled animal study. SETTING: Rehabilitation Center of disabled children, Liaoniang; Department of Rehabilitation, the Second Affiliated Hospital, China Medical University; Department of Rehabilitation Physiotherapy, the First Affiliated Hospital, China Medical University. MATERIALS: A total of 70 healthy Wistar rats aged 18-20 weeks of both genders were selected and randomly divided into 3 groups: sham operation group with 12 rats, control group with 20 rats and treatment group with 38 rats. The treatment group included 4 time points: immediate reperfusion with 6 ones, 6-hour reperfusion with 20 ones, 12-hour reperfusion with 6 ones and 18-hour reperfusion with 6 rats. Main instruments were detailed as follows: magnetic head of rotating magnetic device was 6 cm in diameter; magnetic induction intensity at the surface of magnetic head was 0.25 T in silence; the maximal magnetic induction intensity was 0.09 T at the phase of rotation; the average rotating speed was 2500 r per minute. METHODS: The experiment was carried out in the China Medical University in March 2003. Focal cerebral ischemic animal models were established with modified Longa’s method. Operation was the same in the sham operation, but the thread was inserted as 10 mm. Neurologic impairment was assessed with 5-rating method to screen out cases. Those survivals with grade 1 and grade 2 after ischemia for 2 hours and reperfusion for 24 hours were included in the control group and treatment group. Those in the sham operation group and control group were not treated with RMF. Magnetic head was directed towards the head of rats of the treatment group, and the magnetic head was about 7 mm from skin, treated for 15 minutes. The rats were decapitated to take out brains at 24 hours after reperfusion in each group. Water content of brain and volume of cerebral infarction were assessed with wet-dry weight method and TTC staining, respectively. Activity of superoxide dismutase (SOD), content of malondialdehyde (MDA) and change of brain histomorphology in brain tissue of ischemic side were analyzed. MAIN OUTCOME MEASURES: ① Volume of cerebral infarction and changes of water content in brain; ② measurements of SOD and MDA contents in brain tissue of rats in all groups. RESULTS: A total of 70 qualified animals were involved in the final analysis after rejecting the death and unqualified animal models. ① Water content of brain: Water content of brain in the treatment was less than that in the control group at any time point except the immediate time point, and cerebral edema was relieved [(2.48±0.22)%, (2.32±0.19)%, (2.23±0.36)%, (2.91±0.44)%, P < 0.05]. In addition, there were no significant differences among 6-hour, 12-hour and 18-hour reperfusion groups (P > 0.05). ② Volume of cerebral infarction: The absolute volume of cerebral infarction in the treatment group was smaller than that in the control group [(128.21±15.05), (171.22±40.50) mm3, t =2.438, P < 0.05], and the relative volume of cerebral infarction was smaller than that in the control group [(20.22±1.44)%, (25.17±3.85)%, t =2.95, P < 0.05]. ③ Contents of SOD and MDA in brain tissues: Compared with the control group, the SOD content in the brain tissue in the treatment group increased [(54.54±3.85), (69.52±5.88) kNU/g, t =5.568, P < 0.05], while the MDA content decreased [(0.85±0.06), (1.03±0.09) μmol/g, t =4.076, P < 0.05]. ④ General morphological observation: General morphology manifested that the edema was distinct in the right cerebral hemisphere in the control group, showing fat-like white, shallow anfractuosity, flat gyria, brittle tissue and easy to break up. The edema of right cerebral hemisphere was light and surface was hyperaemia in the treatment group. CONCLUSION: RMF may improve anti-oxidative ability of brain tissue of rats with acute focal cerebral ischemia/reperfusion injury and reduce volume of cerebral infarction and degrees of cerebral edema.
