Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have bee...Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have been extensively utilized to improved high-temperature capacitive performance of dielectric polymers,the presence of thermodynamically incompatible organic and inorganic components may lead to concern about the long-term stability and also complicate film processing.Herein,zero-dimensional polymer dots with high electron affinity are introduced into photoactive allyl-containing poly(aryl ether sulfone)to form the all-organic polymer composites for hightemperature capacitive energy storage.Upon ultraviolet irradiation,the crosslinked polymer composites with polymer dots are efficient in suppressing electrical conduction at high electric fields and elevated temperatures,which significantly reduces the high-field energy loss of the composites at 200℃.Accordingly,the ultraviolet-irradiated composite film exhibits a discharged energy density of 4.2 J cm^(−3)at 200℃.Along with outstanding cyclic stability of capacitive performance at 200℃,this work provides a promising class of dielectric materials for robust high-performance all-organic dielectric nanocomposites.展开更多
Objective: To investigate damage effects of ultraviolet irradiation on eternal keratinocyte-HaCaT cells and to evaluate photo-protective efficiency of hydroxychloroqine and Traditional Chinese Medicines(epigallocatech...Objective: To investigate damage effects of ultraviolet irradiation on eternal keratinocyte-HaCaT cells and to evaluate photo-protective efficiency of hydroxychloroqine and Traditional Chinese Medicines(epigallocatechingallate[EGCG], baikal skullcap root and szechwan lovge rhizome) on HaCaT cells damaged by middle wave ultraviolet(UVB) irradiation. Methods: Subconfluent HaCaT cells were sham or UVB irradiated and treated with above TCM agents. The damage degree of HaCaT cells was observed by a light microscop. Cell growth was recorded by cell count and cellular activity was detected by MTT method. The secretion amount of IL-6 and TNF-α was measured by ELISA. Results: The irradiation damage of HaCaT cells was depended on the irradiated dosages and cellular activity was reduced by 36%-80%, with a maximum decrease over 90% after 72 h. The intervention of the above drugs may increase the cellular activity by 10%-72%. The photo-protective efficiency was more apparent in EGCG (from 1.19±0.07 to 1.28±0.06, P<0.01) than that in hydroxychloroqine (from 0.43±0.04 to 0.96±0.04, P<0.05). The other two tested drugs also showed photo-protective effect(from 0.44±0.07 to 1.21±0.02, P<0.05). As to cytokine secretion, EGCG could decline the secretion amount of IL-6 and TNF-α apparently. Hydroxychloroqine and baikal skullcap root baikal skullcap root could only reduce the secretion of IL-6. The secretion of IL-6 and TNF-α could not be inhibited by szechwan lovge rhizome. Conclusion: The injury effect of UVB irradiation on cultured keratinocytes is dose-dependent and the tested drugs have photo-protective potency. Inhibition of cytokine secretion may be one of the mechanisms related to reducing the damage effect of UVB irradiation.展开更多
Objective:To investigate the treatment effect of combined application of localized ultraviolet irradiation and Shengji Yuhong Cream on diabetic foot patients.Methods:Diabetic foot patients in the control group were tr...Objective:To investigate the treatment effect of combined application of localized ultraviolet irradiation and Shengji Yuhong Cream on diabetic foot patients.Methods:Diabetic foot patients in the control group were treated with localized ultraviolet irradiation on the basis of conventional treatment.The study group was added with Shengji Yuhong Cream on top of the localized ultraviolet irradiation on the basis of conventional treatment.Results:The results of ankle brachial index and dorsal foot skin temperature of that two groups before treatment were compared,P>0.05.After treatment,the ankle brachial index and dorsal foot skin temperature of the study group were better than those of the control group.The comparison between the groups and within the group was P<0.05.The total effective rate of the study group(95.65%)was higher than that of the control group(71.11%),P<0.05.Conclusion:The application of localized ultraviolet irradiation and Shengji Yuhong Cream in the treatment of diabetic foot is effective.展开更多
The reductive perturbation method is applied to investigate the dust acoustic soliton in dusty plasmas with streaming ions under ultraviolet irradiation theoretically and numerically.The self-consistent dust charge va...The reductive perturbation method is applied to investigate the dust acoustic soliton in dusty plasmas with streaming ions under ultraviolet irradiation theoretically and numerically.The self-consistent dust charge variation is taken into account.It is shown that the ultraviolet irradiation can significantly lower the magnitude of the dust negative charge,and ion streaming velocity firstly raise the magnitude of the dust negative charge and then lower it.With the growth of(Ultraviolet) UV photo flux or ion streaming velocity,the phase velocity and width of the solitary waves decrease, whereas its amplitude increases.展开更多
A high turnover number was achieved in the photocatalytic carbonylation of C - H bonds of cyclohexane catalyzed by Co (acac)2 under ambient conditions (1 atm,25℃) to give mainly cyclohexanecarboxaldehyde.
Objective:To study the therapy effect of ultraviolet blood irradiation and oxygenation (UBIO) on blood AChe activity and lung injury due to acute soman intoxication in rabbits. Methods:Forty rabbits were randomly di...Objective:To study the therapy effect of ultraviolet blood irradiation and oxygenation (UBIO) on blood AChe activity and lung injury due to acute soman intoxication in rabbits. Methods:Forty rabbits were randomly divided into 4 groups: normal control group, intoxication group, routine therapy group and UBIO therapy group. Blood AChe activity and artery blood gas were analyzed 2 h after intoxication. ACP and AKP activities in BALF were determined respectively. Results:Blood AChe activity in intoxication group was lower than that in normal control group (P<0.05). BALF ACP and AKP activities in intoxication group were higher than that in normal control group. Blood AChe activities in UBIO therapy group increased and were higher than that in intoxication and routine therapy groups. Compared with intoxication group, BALF ACP and AKP activities were decreased (P<0.05) in UBIO therapy group, while artery blood pH, PaO2 and SaO2 increased (P<0.05). Conclusion: UBIO therapy can elevate blood AChe activity and alleviate lung injury induced by soman intoxication. So it may be a new way to treat acute soman intoxication.展开更多
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 random...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.展开更多
AIM: To establish whether d-limonene can protect against induction of cyclobutane pyrimidine dimers(CPDs) and sunburn in ultraviolet irradiation(UVR) irradiated mouse skin. METHODS: The d-limonene was given in 4 daily...AIM: To establish whether d-limonene can protect against induction of cyclobutane pyrimidine dimers(CPDs) and sunburn in ultraviolet irradiation(UVR) irradiated mouse skin. METHODS: The d-limonene was given in 4 daily oral 20 μL aliquots at different concentrations as follows: 100%, 10% or 1% in liponate and 100% liponate as control. One day after the final d-limonene treatment, the mice were anesthetized with i.p. sodium pentobarbital and placed in boxes to allow a rectangular(2 cm × 4 cm) region of dorsal skin to be irradiated with a single, ultraviolet radiation dose of 1.5 kJ /m2. Skin samples from UVR irradiated area were obtained at 5 min after UVR exposure for CPD detection, at 6 d after UVR exposure, skin samples were obtained for in situ analysis for N-myc downstream regulating gene 1(NDRG1)(a stress response gene), proliferating cell nuclear antigen(PCNA)(an S-phase marker) and filaggrin(a barrier integrity gene). Based on immunohistochemistry staining, the number of CPD, NDRG1 and PCNA positive cells, as well as unstained cells was counted in 3 different individually selected areas and percentage of positive cells was established. RESULTS: CPD reduction occurred as follows: liponate only-none; 1% d-limonene-54.3% reduction of CPDs; 10% d-limonene-73.4% reduction of CPDs; 100% d-limonene-86.1% reduction of CPDs, the latter equivalent to a UV dose of only 0.21 k J/m2. Sunburn was also dose-dependently reduced by d-limonene. The NDRG1 protein was strongly induced by UVR(70.0% ± 10.4% positive cells), but 1% d-limonene reduced the response to 64.6% ± 9.2%, 10% d-limonene reduced the response to 16.2% ± 3.4% and 100% d-limonene reduced the response to 6.3% ± 1.7%. Similarly, PCNA was 52.4% ± 9.9% positive in UVR exposed skin, and 1% d-limonene reduced it to 42.9% ± 8.1%, 10% d-limonene reduced it to 36.2% ± 6.7% and 100% d-limonene reduce it to 13.8% ± 3.4%. NDRG1 and PCNA were increased by d-limonene or UVR separately, but combined they produced less than either agent separately owing to the protective effect of pre-exposure to d-limonene. CONCLUSION: Overall d-limonene acted to protect against ultraviolet B-induced DNA photodamage and sunburn in UVR exposed skin.展开更多
BACKGROUND: Ultraviolet blood irradiation and oxygenation (UBIO) has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear. OBJECTIVE: To o...BACKGROUND: Ultraviolet blood irradiation and oxygenation (UBIO) has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear. OBJECTIVE: To observe the effect of UBIO on the nerve function and activities of K^+-Na^+-ATPase and Ca2^+-Mg2^+-ATPase activities on the red blood cell (RBC) membrane of patients with acute cerebral infarction. DESIGN: A randomized and controlled study.SETTING: Department of Neurology, Xiangfan Central Hospital.PARTICIPANTS: From January 2000 to December 2001, excluding those above 70 years old, 58 cases of 700 patients with acute cerebral infarction admitted in the Department of Neurology, Xiangfan Central Hospital, were recruited and divided into two groups according to the random number table: UBIO treated group (n=28), including 17 males and 11 females, aged 40-68 years; and control group (n=30), including 20 males and 10 females, aged 44-69 years. All the patients agreed to participate in the therapeutic program and detected items. The general informations were comparable without obvious differences between the two groups (P 〉 0.05).METHODS: ① The patients in both groups received routine treatments, besides, those in the UBIO treated group were given UBIO treatment by using the XL-200 type therapeutic apparatus produced in Shijiazhuang, whose ultraviolet wave was set at 253.7 nm with the energy density of 0.568 J/m^2 per second, UBIO treatment started from the second day after admission, once every other day, with a single course consisting of 5-7 treatments. ② In the UBIO treated group, the venous blood was sampled before and after the first, third and the completion of the treatment course respectively, the venous blood was taken at each corresponding time point in the control group. After centrifugation of the blood at 10 000 rounds per minute, the RBC membrane was separated and then the activities of K^+-Na^+-ATPase and Ca2^+-Mg2^+-ATPase were detected by means of phosphorus determination.③ The nerve function was scored before and after treatment in both groups with European stroke scale, which included 13 items, the total score was 0-100 points, the higher the score, the better the nerve function. MAIN OUTCOME MEASURES :①Score of European stroke scale before and after treatment in both groups.② Comparison of the activities of K^+-Na^+-ATPase and Ca2^+-Mg2^+-ATPase on RBC membrane between the two groups before treatment and after the first, third and the completion of the treatment. RESULTS: All the 58 patients with cerebral infarction were involved in the analysis of results.① The score of European stroke scale had no obvious difference between the two groups [(49.31±11.48), (50.58±12.63), P 〉 0.05], and it was obviously higher in the UBIO treated group than in the control group after treatment [84.66±13.75), (77.05±11.17), P 〈 0.05].②The activity of K^+-Na^+-ATPase on RBC membrane in the UBIO treated group was significantly increased after the first and third treatment as compared with before treatment [(31.56±19.25), (27.64±15.83), (17.67±13.83), P 〈 0.01], it was still higher after the completion of the treatment than before treatment without obvious difference [(20.86±14.53), P 〉 0.05]. After the first and third treatment, it was obviously higher in the UBIO treated group than in the control group [19.31±11.88), (17.44±10.42), P 〈 0.01]. ③ In the UBIO treated group, Ca2^+-Mg2^+-ATPase activity on RBC membrane significantly increased after the first treatment and remained higher than the pre-treatment level throughout the treatment [(27.49±14.72), (17.41±4.82), P 〈 0.01]. The activity of Ca2^+-Mg2^+-ATPase on RBC membrane was markedly higher in the UBIO treated group than in the control group after after the first, third and the completion of treatment respectively [(24.83±12.88), (17.70±5.69); (28.08±13.44), (16.32±5.29); (17.42±6.04), P〈 0.05-0.01]. CONCLUSION: The effect of UBIO treatment against acute cerebral infarction may be mediated by the increased K^+-Na^+ ATPase and Ca2^+-Mg2^+-ATPase activities on RBC membrane, which enhances the RBC transformation ability so as to lower RBC aggregation and correct high blood viscosity.展开更多
Bormate (BrO3^-) is a carcinogenic chemical produced in ozonation or chlorination of bromide-containing water. Although its formation in seawater with or without sunlight has been previously investigated, the format...Bormate (BrO3^-) is a carcinogenic chemical produced in ozonation or chlorination of bromide-containing water. Although its formation in seawater with or without sunlight has been previously investigated, the formation of bromate in dilute solutions, particularly raw water for water treatment plant, is unknown. In this article, the results of bench scale tests to measure the formation rates of bromate formation in dilute solutions, including de-ionized water and raw water from Yangtze River, were presented in dark chlorination and ultraviolet (UV)/chlorination processes. And the effects of initial pH, initial concentration of NaOCl, and UV light intensity on bromate formation in UV/chlorination of the diluted solutions were investigated. Detectable bromate was formed in dark chlorination of the two water samples with a relatively slow production rate. Under routine disinfecting conditions, the amount of formed bromate is not likely to exceed the national standards (10 μg/L). UV irradiation enhanced the decay of free chlorine, and, simultaneously, 6.6%-32% of Br^- was oxidized to BrO3^-. And the formation of bromate exhibited three stages: rapid stage, slow stage and plateau. Under the experimental conditions (pH = 4.41-11.07, CCl2= 1.23-4.50 mg/L), low pH and high chlorine concentration favored the generation of bromate. High light intensity promoted the production rate of bromate, but decreased its total generation amount due to acceleration of chlorine decomposition.展开更多
High photoactive TiO2 catalyst was prepared using the sol-gel method through UV irradiation during the formation stage of nuclei. The surface morphology and microstructure of the prepared catalyst were characterized u...High photoactive TiO2 catalyst was prepared using the sol-gel method through UV irradiation during the formation stage of nuclei. The surface morphology and microstructure of the prepared catalyst were characterized using scanning electron microscopy (SEM), X-ray diffraction patterns (XRD), and Fourier transform infrared spectroscopy (FF-IR). The photoactivity was evaluated by the degradation of methylene blue. The results show that the photocatalysis of the prepared catalyst is higher than that of conventional heat-treated particles. The higher photoactivity is a combined result of favorable microstructure, appropriate hydroxyl groups, and active sites of Ti^3+ ions on the surface of TiO2. It is concluded that the ultraviolet irradiation-induced sol-gel method is an effective method to enhance the photocatalysis of TiO2.展开更多
The purpose of the present study was to compare the effects of different doses of ultraviolet radiation A1 (UVA1) on human fibroblast proliferation and collagen level in a mouse model of scleroderma, so as to identi...The purpose of the present study was to compare the effects of different doses of ultraviolet radiation A1 (UVA1) on human fibroblast proliferation and collagen level in a mouse model of scleroderma, so as to identify appropriate irradiation doses for clinical treatment of scleroderma. Monolayer from human fibroblasts was cultured in vitro, and a mouse model of scleroderma was established by subcutaneous injection of 100 μL of 400 μg/mL bleomycin into the back of BALB/c mice for 4 weeks. The mouse models and human fibroblasts were divided into UVA1- exposed (100, 60 and 20 J/cm2) and UVA-unexposed groups. At 0, 24 and 48 h after exposure, cell proliferation and levels of hydroxyproline and collagen were detected. UVA1 irradiation was performed 3 times weekly for 10 weeks, and the pathological changes of skin tissues, skin thickness and collagen level were observed after phototherapy. Cell proliferation and the levels of hydroxyproline and collagen were inhibited after phototherapy, and there was a significant difference between the UVAl-exposed cells and UVAl-unexposed cells (P 〈 0.001). In addition, UVA1 phototherapy improved dermal sclerosis and softened the skin, and there were significant differences between the high-dose UVA1 group and the model group, and the negative group (P 〈 0.05). It is concluded that UVA1 radiation can reduce cell proliferation, and decrease hydroxyproline and collagen levels in a dose-dependent manner in vitro. High-dose UVA1 phototherapy has marked therapeutic effect on scleroderma in the mouse model. Decreased collagen level may be related to the reduced number and activity of cells, as well as inhibition of collagen synthesis.展开更多
基金the National Natural Science Foundation of China(No.51973080,92066104).
文摘Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have been extensively utilized to improved high-temperature capacitive performance of dielectric polymers,the presence of thermodynamically incompatible organic and inorganic components may lead to concern about the long-term stability and also complicate film processing.Herein,zero-dimensional polymer dots with high electron affinity are introduced into photoactive allyl-containing poly(aryl ether sulfone)to form the all-organic polymer composites for hightemperature capacitive energy storage.Upon ultraviolet irradiation,the crosslinked polymer composites with polymer dots are efficient in suppressing electrical conduction at high electric fields and elevated temperatures,which significantly reduces the high-field energy loss of the composites at 200℃.Accordingly,the ultraviolet-irradiated composite film exhibits a discharged energy density of 4.2 J cm^(−3)at 200℃.Along with outstanding cyclic stability of capacitive performance at 200℃,this work provides a promising class of dielectric materials for robust high-performance all-organic dielectric nanocomposites.
文摘Objective: To investigate damage effects of ultraviolet irradiation on eternal keratinocyte-HaCaT cells and to evaluate photo-protective efficiency of hydroxychloroqine and Traditional Chinese Medicines(epigallocatechingallate[EGCG], baikal skullcap root and szechwan lovge rhizome) on HaCaT cells damaged by middle wave ultraviolet(UVB) irradiation. Methods: Subconfluent HaCaT cells were sham or UVB irradiated and treated with above TCM agents. The damage degree of HaCaT cells was observed by a light microscop. Cell growth was recorded by cell count and cellular activity was detected by MTT method. The secretion amount of IL-6 and TNF-α was measured by ELISA. Results: The irradiation damage of HaCaT cells was depended on the irradiated dosages and cellular activity was reduced by 36%-80%, with a maximum decrease over 90% after 72 h. The intervention of the above drugs may increase the cellular activity by 10%-72%. The photo-protective efficiency was more apparent in EGCG (from 1.19±0.07 to 1.28±0.06, P<0.01) than that in hydroxychloroqine (from 0.43±0.04 to 0.96±0.04, P<0.05). The other two tested drugs also showed photo-protective effect(from 0.44±0.07 to 1.21±0.02, P<0.05). As to cytokine secretion, EGCG could decline the secretion amount of IL-6 and TNF-α apparently. Hydroxychloroqine and baikal skullcap root baikal skullcap root could only reduce the secretion of IL-6. The secretion of IL-6 and TNF-α could not be inhibited by szechwan lovge rhizome. Conclusion: The injury effect of UVB irradiation on cultured keratinocytes is dose-dependent and the tested drugs have photo-protective potency. Inhibition of cytokine secretion may be one of the mechanisms related to reducing the damage effect of UVB irradiation.
文摘Objective:To investigate the treatment effect of combined application of localized ultraviolet irradiation and Shengji Yuhong Cream on diabetic foot patients.Methods:Diabetic foot patients in the control group were treated with localized ultraviolet irradiation on the basis of conventional treatment.The study group was added with Shengji Yuhong Cream on top of the localized ultraviolet irradiation on the basis of conventional treatment.Results:The results of ankle brachial index and dorsal foot skin temperature of that two groups before treatment were compared,P>0.05.After treatment,the ankle brachial index and dorsal foot skin temperature of the study group were better than those of the control group.The comparison between the groups and within the group was P<0.05.The total effective rate of the study group(95.65%)was higher than that of the control group(71.11%),P<0.05.Conclusion:The application of localized ultraviolet irradiation and Shengji Yuhong Cream in the treatment of diabetic foot is effective.
基金Supported by the National Natural Science Fundation of China(Y05033A030)
文摘The reductive perturbation method is applied to investigate the dust acoustic soliton in dusty plasmas with streaming ions under ultraviolet irradiation theoretically and numerically.The self-consistent dust charge variation is taken into account.It is shown that the ultraviolet irradiation can significantly lower the magnitude of the dust negative charge,and ion streaming velocity firstly raise the magnitude of the dust negative charge and then lower it.With the growth of(Ultraviolet) UV photo flux or ion streaming velocity,the phase velocity and width of the solitary waves decrease, whereas its amplitude increases.
文摘A high turnover number was achieved in the photocatalytic carbonylation of C - H bonds of cyclohexane catalyzed by Co (acac)2 under ambient conditions (1 atm,25℃) to give mainly cyclohexanecarboxaldehyde.
文摘Objective:To study the therapy effect of ultraviolet blood irradiation and oxygenation (UBIO) on blood AChe activity and lung injury due to acute soman intoxication in rabbits. Methods:Forty rabbits were randomly divided into 4 groups: normal control group, intoxication group, routine therapy group and UBIO therapy group. Blood AChe activity and artery blood gas were analyzed 2 h after intoxication. ACP and AKP activities in BALF were determined respectively. Results:Blood AChe activity in intoxication group was lower than that in normal control group (P<0.05). BALF ACP and AKP activities in intoxication group were higher than that in normal control group. Blood AChe activities in UBIO therapy group increased and were higher than that in intoxication and routine therapy groups. Compared with intoxication group, BALF ACP and AKP activities were decreased (P<0.05) in UBIO therapy group, while artery blood pH, PaO2 and SaO2 increased (P<0.05). Conclusion: UBIO therapy can elevate blood AChe activity and alleviate lung injury induced by soman intoxication. So it may be a new way to treat acute soman intoxication.
文摘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.
基金Supported by NCI Center Grant CA16087(NYU Kaplan Cancer)NIEHS Center Grant(Nelson Institute of the NYU Schoolof Medicine)Biokeys for Flavors,LLC,No.ES00260
文摘AIM: To establish whether d-limonene can protect against induction of cyclobutane pyrimidine dimers(CPDs) and sunburn in ultraviolet irradiation(UVR) irradiated mouse skin. METHODS: The d-limonene was given in 4 daily oral 20 μL aliquots at different concentrations as follows: 100%, 10% or 1% in liponate and 100% liponate as control. One day after the final d-limonene treatment, the mice were anesthetized with i.p. sodium pentobarbital and placed in boxes to allow a rectangular(2 cm × 4 cm) region of dorsal skin to be irradiated with a single, ultraviolet radiation dose of 1.5 kJ /m2. Skin samples from UVR irradiated area were obtained at 5 min after UVR exposure for CPD detection, at 6 d after UVR exposure, skin samples were obtained for in situ analysis for N-myc downstream regulating gene 1(NDRG1)(a stress response gene), proliferating cell nuclear antigen(PCNA)(an S-phase marker) and filaggrin(a barrier integrity gene). Based on immunohistochemistry staining, the number of CPD, NDRG1 and PCNA positive cells, as well as unstained cells was counted in 3 different individually selected areas and percentage of positive cells was established. RESULTS: CPD reduction occurred as follows: liponate only-none; 1% d-limonene-54.3% reduction of CPDs; 10% d-limonene-73.4% reduction of CPDs; 100% d-limonene-86.1% reduction of CPDs, the latter equivalent to a UV dose of only 0.21 k J/m2. Sunburn was also dose-dependently reduced by d-limonene. The NDRG1 protein was strongly induced by UVR(70.0% ± 10.4% positive cells), but 1% d-limonene reduced the response to 64.6% ± 9.2%, 10% d-limonene reduced the response to 16.2% ± 3.4% and 100% d-limonene reduced the response to 6.3% ± 1.7%. Similarly, PCNA was 52.4% ± 9.9% positive in UVR exposed skin, and 1% d-limonene reduced it to 42.9% ± 8.1%, 10% d-limonene reduced it to 36.2% ± 6.7% and 100% d-limonene reduce it to 13.8% ± 3.4%. NDRG1 and PCNA were increased by d-limonene or UVR separately, but combined they produced less than either agent separately owing to the protective effect of pre-exposure to d-limonene. CONCLUSION: Overall d-limonene acted to protect against ultraviolet B-induced DNA photodamage and sunburn in UVR exposed skin.
文摘BACKGROUND: Ultraviolet blood irradiation and oxygenation (UBIO) has obtained better clinical effect in treating acute cerebral infarction, but the mechanism underlying this effect remains unclear. OBJECTIVE: To observe the effect of UBIO on the nerve function and activities of K^+-Na^+-ATPase and Ca2^+-Mg2^+-ATPase activities on the red blood cell (RBC) membrane of patients with acute cerebral infarction. DESIGN: A randomized and controlled study.SETTING: Department of Neurology, Xiangfan Central Hospital.PARTICIPANTS: From January 2000 to December 2001, excluding those above 70 years old, 58 cases of 700 patients with acute cerebral infarction admitted in the Department of Neurology, Xiangfan Central Hospital, were recruited and divided into two groups according to the random number table: UBIO treated group (n=28), including 17 males and 11 females, aged 40-68 years; and control group (n=30), including 20 males and 10 females, aged 44-69 years. All the patients agreed to participate in the therapeutic program and detected items. The general informations were comparable without obvious differences between the two groups (P 〉 0.05).METHODS: ① The patients in both groups received routine treatments, besides, those in the UBIO treated group were given UBIO treatment by using the XL-200 type therapeutic apparatus produced in Shijiazhuang, whose ultraviolet wave was set at 253.7 nm with the energy density of 0.568 J/m^2 per second, UBIO treatment started from the second day after admission, once every other day, with a single course consisting of 5-7 treatments. ② In the UBIO treated group, the venous blood was sampled before and after the first, third and the completion of the treatment course respectively, the venous blood was taken at each corresponding time point in the control group. After centrifugation of the blood at 10 000 rounds per minute, the RBC membrane was separated and then the activities of K^+-Na^+-ATPase and Ca2^+-Mg2^+-ATPase were detected by means of phosphorus determination.③ The nerve function was scored before and after treatment in both groups with European stroke scale, which included 13 items, the total score was 0-100 points, the higher the score, the better the nerve function. MAIN OUTCOME MEASURES :①Score of European stroke scale before and after treatment in both groups.② Comparison of the activities of K^+-Na^+-ATPase and Ca2^+-Mg2^+-ATPase on RBC membrane between the two groups before treatment and after the first, third and the completion of the treatment. RESULTS: All the 58 patients with cerebral infarction were involved in the analysis of results.① The score of European stroke scale had no obvious difference between the two groups [(49.31±11.48), (50.58±12.63), P 〉 0.05], and it was obviously higher in the UBIO treated group than in the control group after treatment [84.66±13.75), (77.05±11.17), P 〈 0.05].②The activity of K^+-Na^+-ATPase on RBC membrane in the UBIO treated group was significantly increased after the first and third treatment as compared with before treatment [(31.56±19.25), (27.64±15.83), (17.67±13.83), P 〈 0.01], it was still higher after the completion of the treatment than before treatment without obvious difference [(20.86±14.53), P 〉 0.05]. After the first and third treatment, it was obviously higher in the UBIO treated group than in the control group [19.31±11.88), (17.44±10.42), P 〈 0.01]. ③ In the UBIO treated group, Ca2^+-Mg2^+-ATPase activity on RBC membrane significantly increased after the first treatment and remained higher than the pre-treatment level throughout the treatment [(27.49±14.72), (17.41±4.82), P 〈 0.01]. The activity of Ca2^+-Mg2^+-ATPase on RBC membrane was markedly higher in the UBIO treated group than in the control group after after the first, third and the completion of treatment respectively [(24.83±12.88), (17.70±5.69); (28.08±13.44), (16.32±5.29); (17.42±6.04), P〈 0.05-0.01]. CONCLUSION: The effect of UBIO treatment against acute cerebral infarction may be mediated by the increased K^+-Na^+ ATPase and Ca2^+-Mg2^+-ATPase activities on RBC membrane, which enhances the RBC transformation ability so as to lower RBC aggregation and correct high blood viscosity.
文摘Bormate (BrO3^-) is a carcinogenic chemical produced in ozonation or chlorination of bromide-containing water. Although its formation in seawater with or without sunlight has been previously investigated, the formation of bromate in dilute solutions, particularly raw water for water treatment plant, is unknown. In this article, the results of bench scale tests to measure the formation rates of bromate formation in dilute solutions, including de-ionized water and raw water from Yangtze River, were presented in dark chlorination and ultraviolet (UV)/chlorination processes. And the effects of initial pH, initial concentration of NaOCl, and UV light intensity on bromate formation in UV/chlorination of the diluted solutions were investigated. Detectable bromate was formed in dark chlorination of the two water samples with a relatively slow production rate. Under routine disinfecting conditions, the amount of formed bromate is not likely to exceed the national standards (10 μg/L). UV irradiation enhanced the decay of free chlorine, and, simultaneously, 6.6%-32% of Br^- was oxidized to BrO3^-. And the formation of bromate exhibited three stages: rapid stage, slow stage and plateau. Under the experimental conditions (pH = 4.41-11.07, CCl2= 1.23-4.50 mg/L), low pH and high chlorine concentration favored the generation of bromate. High light intensity promoted the production rate of bromate, but decreased its total generation amount due to acceleration of chlorine decomposition.
文摘High photoactive TiO2 catalyst was prepared using the sol-gel method through UV irradiation during the formation stage of nuclei. The surface morphology and microstructure of the prepared catalyst were characterized using scanning electron microscopy (SEM), X-ray diffraction patterns (XRD), and Fourier transform infrared spectroscopy (FF-IR). The photoactivity was evaluated by the degradation of methylene blue. The results show that the photocatalysis of the prepared catalyst is higher than that of conventional heat-treated particles. The higher photoactivity is a combined result of favorable microstructure, appropriate hydroxyl groups, and active sites of Ti^3+ ions on the surface of TiO2. It is concluded that the ultraviolet irradiation-induced sol-gel method is an effective method to enhance the photocatalysis of TiO2.
文摘The purpose of the present study was to compare the effects of different doses of ultraviolet radiation A1 (UVA1) on human fibroblast proliferation and collagen level in a mouse model of scleroderma, so as to identify appropriate irradiation doses for clinical treatment of scleroderma. Monolayer from human fibroblasts was cultured in vitro, and a mouse model of scleroderma was established by subcutaneous injection of 100 μL of 400 μg/mL bleomycin into the back of BALB/c mice for 4 weeks. The mouse models and human fibroblasts were divided into UVA1- exposed (100, 60 and 20 J/cm2) and UVA-unexposed groups. At 0, 24 and 48 h after exposure, cell proliferation and levels of hydroxyproline and collagen were detected. UVA1 irradiation was performed 3 times weekly for 10 weeks, and the pathological changes of skin tissues, skin thickness and collagen level were observed after phototherapy. Cell proliferation and the levels of hydroxyproline and collagen were inhibited after phototherapy, and there was a significant difference between the UVAl-exposed cells and UVAl-unexposed cells (P 〈 0.001). In addition, UVA1 phototherapy improved dermal sclerosis and softened the skin, and there were significant differences between the high-dose UVA1 group and the model group, and the negative group (P 〈 0.05). It is concluded that UVA1 radiation can reduce cell proliferation, and decrease hydroxyproline and collagen levels in a dose-dependent manner in vitro. High-dose UVA1 phototherapy has marked therapeutic effect on scleroderma in the mouse model. Decreased collagen level may be related to the reduced number and activity of cells, as well as inhibition of collagen synthesis.