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Causal relationship between circulating vitamin C and 25-hydroxyvitamin D concentrations and common mental disorders-a Mendelian randomization study
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作者 Yuanyuan Wang Lirong Dong +8 位作者 Meng Zhao Shiyu Yin Pan Da Dengfeng Xu Yifei Lu Jiayue Xia Niannian Wang Shaokang Wang Guiju Sun 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1877-1885,共9页
Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D... Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D(25(OH)D)levels and mental disorders.The data used for the MR analysis were derived from the summary genome-wide association studies(GWAS)database for VC and 25(OH)D and from the Finn Gen consortium for fourteen mental disorders.Based on the inverse variance weighted(IVW)method,we found a potential causal association between circulating VC and anxiety disorders(IVW:OR=1.139,95%CI:1.023-1.269,P=0.018).However,no causal association was found between VC or 25(OH)D and other mental disorders(P>0.05).In the reverse MR analysis,individuals with Alzheimer’s disease was causally associated with higher concentrations of circulating VC(P=0.012),while individuals with anxiety disorders had a negative association between the concentrations of 25(OH)D(P=0.012).However,the current evidence does not support a causal relationship between VC or 25(OH)D and other mental disorders.In addition,there was no causal association between circulating VC and 25(OH)D(P>0.05).Future studies are needed to confirm these findings and to elucidate the mechanisms of potential causality. 展开更多
关键词 circulating vitamin c 25-Hydroxyvitamin D Mental disorder Mendelian randomization
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Hemolysis attributed to high dose vitamin C:Two case reports
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作者 Shi-Wan Wang Xiao-Wei Zhang +6 位作者 Jin-Xiu Qu Yi-Zhong Rao Shuai Lu Bing Wang Jia He Yuan Zhao Ben-Qiang Rao 《World Journal of Clinical Cases》 SCIE 2024年第17期3168-3176,共9页
BACKGROUND High-dose vitamin C treatment(HVCT)can reduce the adverse effect of chemotherapy and enhance the effect of antitumor therapy,which has been considered one of the safest alternative treatments.However,the se... BACKGROUND High-dose vitamin C treatment(HVCT)can reduce the adverse effect of chemotherapy and enhance the effect of antitumor therapy,which has been considered one of the safest alternative treatments.However,the severity of its adverse effects may have been underestimated.The most serious adverse effect is hemolysis,which may result in acute kidney injury or death.Although glucose-6-phosphate dehydrogenase(G6PD)deficiency is considered to be the main cause,the probability and pathological mechanism are not completely understood,leading to a lack of effective and standardized treatment methods.CASE SUMMARY Two patients with colorectal cancer developed hemolytic anemia after using 1 g/kg HVCT.In contrast to previous cases,the lowest hemoglobin level in the two cases was<50 g/L,which was lower than previously reported.This may be because Case 1 had chronic hepatitis B for many years,which caused abnormal liver reserve function,and Case 2 had grade II bone marrow suppression.Both patients improved and were discharged after blood replacement therapy.Our cases had the most severe degree of hemolysis but the best prognosis,suggesting that our treatment may be helpful for rescue of drug-induced hemolysis.This is the first review of the literature on hemolysis caused by HVCT,and we found that all patients with G6PD deficiency developed hemolysis after HVCT.CONCLUSION G6PD deficiency should be considered as a contraindication to HVCT,and it is not recommended for patients with bone marrow suppression,moderate-tosevere anemia,hematopoietic abnormalities,or abnormal liver and kidney function.Early blood purification and steroid therapy may avoid acute kidney injury or death caused by HVCT-related hemolytic anemia. 展开更多
关键词 HEMOLYSIS vitamin c Adverse effects Acute kidney injury cANcER case report
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Content Determination of Vitamin C in Durian Endocarp and Optimization of Extraction Process
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作者 Chenxi Xin Jiuying Cui +1 位作者 Zichun Song Yan Li 《Journal of Biosciences and Medicines》 2023年第8期208-218,共11页
Purpose: To optimize the extraction process of vitamin C from durian endocarp, and to determine the content of vitamin C in durian endocarp with high performance liquid chromatography (HPLC). Method: Optimize ultrason... Purpose: To optimize the extraction process of vitamin C from durian endocarp, and to determine the content of vitamin C in durian endocarp with high performance liquid chromatography (HPLC). Method: Optimize ultrasonic extraction conditions by L9 (4<sup>3</sup>) orthogonal experiment by using octadecylsilane chemically bonded silica as the stationary phase, using methanol (A): 0.1% oxalic acid (B) = 5:95 (V/V) as the mobile phase, setting the flow rate as 1.0 mL/min, and setting the wavelength as 254 nm for assay. Result: The optimal extraction process is as follows: the material-liquid ratio is 1:12, the extraction solvent is 2% oxalic acid aqueous solution, and the extraction time is 30 min;Vitamin C has a good linearity within the concentration range of 5.4 - 108.0 mg·mL<sup>-1</sup>, and the regression equation is y = 37698x - 61035 (R<sup>2</sup> = 0.9996);the average recovery rate is 99.03%, the instruments are of high precision with good stability. Conclusion: This extraction process performs well in simplicity, costs and extraction efficiency, which may accelerate the development and utilization of vitamin C extraction from durian endocarp, and provide references to relevant studies and practices. 展开更多
关键词 HPLc Orthogonal Experiment vitamin c Durian Endocarp
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A Study on Emotional Design for Vitamin C Dietary Supplements(Chinese Market,Generation Z Consumers)
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作者 Suimeng Qin Albert Young Choi 《Psychology Research》 2023年第11期527-536,共10页
China,recognized as the world’s largest developing nation,displays considerably lower per capita consumption of dietary supplements in comparison to Asian nations such as Japan and South Korea.However,in recent years... China,recognized as the world’s largest developing nation,displays considerably lower per capita consumption of dietary supplements in comparison to Asian nations such as Japan and South Korea.However,in recent years,there has been a substantial surge in health consciousness among the Chinese populace.This trend is not confined to the middle-aged and elderly;even younger consumer demographics are exhibiting increased health awareness.Consequently,the target demographic for dietary supplements is transitioning towards a younger demographic.Within the Chinese dietary supplement industry,vitamin C has consistently held the largest market share,commanding a broad consumer base.This underscores the substantial role of vitamin C in the dietary supplement sector.In response to the trend towards a younger target demographic in the dietary supplement industry,adjustments are required to accommodate the preferences of this younger consumer group.This research,guided by Norman’s emotional design framework,executed a survey of over 200 respondents to investigate the preferences of Generation Z consumers in China.The research encompassed packaging,product forms,and brand imagery,corresponding to the emotional design’s visceral,behavioral,and reflective layers,with a primary focus on optimally meeting the emotional needs of Generation Z.The findings indicated that consumers favor products in capsule form,packaged in zip-lock.The predominant color scheme is clean white,accented by vibrant orange elements,while emphasizing the product’s health and scientific attributes.This study offers valuable insights for the continued evolution of the vitamin C dietary supplement market in China. 展开更多
关键词 Generation Z consumers vitamin c products emotional design
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Thermally degraded palm kernel oil increased serum 4-hydroxynonenal protein adduct formation and hepatotoxic indications in Wistar rats:vitamin C intervention
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作者 Emeka Chinedu Ifediba Onyenmechi Johnson Afonne 《Toxicology Advances》 2023年第1期1-8,共8页
Objective:The frequent consumption of deep-fried foods has been linked to high risk of certain non-communicable diseases.As a consequence,the safety of deep-fried oil(DFO)ingested with fried foods has been called into... Objective:The frequent consumption of deep-fried foods has been linked to high risk of certain non-communicable diseases.As a consequence,the safety of deep-fried oil(DFO)ingested with fried foods has been called into question.This study therefore evaluated the effects of DFO from palm kernel on serum 4-hydroxynonenal protein adduct formation,De Ritis ratio(DRR),liver histology and atherogenicity in Wistar rats and the role of vitamin C intervention.Methods:Deep-fried oil samples were characterized for total antioxidant capacity(TAC),degradation and metal contamination levels and compared against counterpart unused frying oil(UFO).In the animal experiment,both oil samples,sourced from commercial cooks,were orally administered,for 13 weeks,to sixty-two rats randomly divided into six test groups of two exposure levels alongside vitamin C control.After exposure,serum liver enzyme activities and lipoproteins levels were determined using colorimetric methods,while protein adducts levels were determined using enzyme-linked immunosorbent assay(ELISA).Histopathological examinations of liver tissues were also performed.Results:DFO had significantly lower(P=0.021)TAC,significantly higher(P=0.024)volatile acid and Pb concentrations compared to UFO.Exposure to DFO significantly increased(P<0.01)serum protein adduct formation,the De Ritis ratio and caused cytoplasmic vacuolation and pigment deposit on liver tissues compared to the control.Additionally,DFO exposures had an initial negative body weight gain rate that increased at the end of the study.Conclusion:However,co-administration of vitamin C significantly reduced(P<0.05)the De Ritis ratio and reduced the serum protein adducts levels by at least 15%.Concomitant intake of vitamin C and DFO can mitigate probable adverse effects. 展开更多
关键词 deep-fried 4-HYDROXYNONENAL HEPATOTOXIcITY vitamin c oil octanoic
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A Meta-Analysis of the Effectiveness of Vitamin C in the Prevention and Treatment of Childhood Upper Respiratory Tract Infections
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作者 Haitham Saeed Mohamed EA Abdelrahim 《Journal of Clinical and Nursing Research》 2023年第1期30-37,共8页
Background:The effectiveness of vitamin C in the prevention and treatment of pediatric upper respiratory tract infections was evaluated in a meta-analysis.Methods:A total 2,573 children with upper respiratory tract in... Background:The effectiveness of vitamin C in the prevention and treatment of pediatric upper respiratory tract infections was evaluated in a meta-analysis.Methods:A total 2,573 children with upper respiratory tract infections were included in the meta-analysis,1,280 of whom received vitamin C and 1,293 who received control medication.The analysis of findings related to the studies included was done through random or fixed effects model to determine whether vitamin C supplementation could stop and control upper respiratory tract infections in children using mean difference(MD)with 95%confidence intervals(CIs).Results:On average,vitamin C-treated children had fewer upper respiratory tract infection bouts,their illness lasted shorter(MD-0.84;95%CI-1.47 to-0.20,P=0.009),and they were less contagious than the control.Conclusions:The number of episodes and illness duration of upper respiratory tract-infected pediatric subjects were considerably reduced in the intervention group(vitamin C)compared to the control.Due to the small sample size in four of 11 studies and the limited number of studies included for comparison,the outcomes should be carefully examined. 展开更多
关键词 vitamin c Upper respiratory tract infection Number of episodes Duration of illness
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TR-ESR Investigation on Reaction of Vitamin C with Excited Triplet of 9,10-phenanthrenequinone in Reversed Micelle Solutions 被引量:1
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作者 许新胜 史蕾 +2 位作者 刘毅 季学韩 崔执凤 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第2期150-154,I0003,共6页
Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C (VC) and the triplet excited states of 9,10-phenanthrenequinone (PAQ) in ethylene glycol-water (E... Time-resolved electron spin resonance has been used to study quenching reactions between the antioxidant Vitamin C (VC) and the triplet excited states of 9,10-phenanthrenequinone (PAQ) in ethylene glycol-water (EG-H2O) homogeneous and inhomogeneous reversed micelle solutions. Reversed micelle solutions were used to be the models of physiological environment of biological cell and tissue. In PAQ/EG-H2O homogeneous solution, the excited triplet of PAQ (3PAQ*) abstracts hydrogen atom from solvent EG. In PAQ/VC/EG-H2O solution, 3pAQ* abstracts hydrogen atom not only from solvent EG but also from VC. The quenching rate constant of 3pAQ* by VC is close to the diffusion-controlled value of 1.41 × 108 L/(mol.s). In hexadecyltrimethylammonium bromide (CTAB)/EG-H2O and aerosol OT (AOT)/EG- H2O reversed micelle solutions, 3pAQ* and VC react around the water-oil interface of the reversed micelle. Exit of 3pAQ* from the lipid phase slows down the quenching reaction. For Triton X-100 (TX-100)/EG-H2O reversed micelle solution, PAQ and VC coexist inside the hydrophilic polyethylene glycol core, and the quenching rate constant of 3pAQ* by VC is larger than those in AOT/EG-H2O and CTAB/EG-H2O reversed micelle solutions, even a little larger than that in EG-H2O homogeneous solution. The strong emissive chemically induced dynamic electron polarization of As'- resulted from the effective TM spin polarization transfer in hydrogen abstraction of 3pAQ* from VC. 展开更多
关键词 9 10-phenanthrenequinone vitamin c Time-resolved electron spin resonance Reversed micelle
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Exploring the effectiveness of in ovo feeding of vitamin C based on the embryonic vitamin C synthesis and absorption in broiler chickens
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作者 Yufei Zhu Jianfei Zhao +6 位作者 Chenxu Wang Fei Zhang Xinhuo Huang Zhouzheng Ren Xin Yang Yanli Liu Xiaojun Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第1期280-287,共8页
Background:Many researches about in ovo feeding(IOF)of vitamin C(VC)are gradually carried out to explore physiological development in chicken,but little studies focus on VC synthesis capacity of the embryo itself,the ... Background:Many researches about in ovo feeding(IOF)of vitamin C(VC)are gradually carried out to explore physiological development in chicken,but little studies focus on VC synthesis capacity of the embryo itself,the selection of injection site and the effectiveness of IOF of VC.This study aims to explore the above problems.Results:Kidney and yolk sac were the main organs for VC synthesis and L-gulonolactone oxidase(GLO)expression was lower during pre-hatch development than that during post-hatch development.Sodium-dependent vitamin C transporter 1(SVCT1)expression was increased continuously in yolk sac from embryonic age 19(E19)to post-hatch day 1(D1)and in intestine(duodenum,jejunum and ileum)from E17 to D1.Plasma VC content was higher at D1 than that at D21 and D42.IOF of VC significantly reduced GLO expression in liver,kidney and yolk sac as well as SVCT1 expression in duodenum,jejunum and ileum,but increased the VC content in plasma,brain,kidney and liver.In addition,IOF of VC obviously reduced the embryonic morality and increased the hatchability under heat stress.Conclusions:This study suggested that IOF of VC at E11 in yolk was effective for embryonic VC supplementation.These findings provide a theoretical reference about the method of embryonic VC supplementation and effective methodology on embryonic VC nutrition in broiler chickens. 展开更多
关键词 In ovo feeding L-gulonolactone oxidase Sodium-dependent vitamin c transporter vitamin c YOLK
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Study of Synthetic Process of Vitamin C
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作者 WANG Jing-chen CUI Feng-xia REN Bao-zeng 《Chinese Food Science》 2012年第2期8-10,共3页
[ Objective] The aim was to find optimum reaction conditions for synthetic process of Vitamin C. [ Method] Vitamin C sodium was used as raw material to prepare vitamin C through acidification, separation, desalination... [ Objective] The aim was to find optimum reaction conditions for synthetic process of Vitamin C. [ Method] Vitamin C sodium was used as raw material to prepare vitamin C through acidification, separation, desalination, recovery and purification. The impact of reaction time, tempera-ture, feedstock molar ratio and water content on the yield of vitamin C were investigated in the experiment. [Result] The optimum reaction condi- tions for synthetic process of Vitamin C were as follows: in the acidification test, reaction time 120 min, temperature 20 -30 ℃, the molar ratio be-tween hydrochloric acid and Vitamin C sodium 1 : 1 and water content 41.0%. Under the above condition, the purity and yield of vitamin C reach 99.80% and 94.74% respectively. [Conclusion] The process can decrease consumption, enhance quality and recover of the product, improve the environmental pollution, shorten processing periods and reduce production cost. Thus, the process is suitable for industrialization. Key words Vitamin C; Vitamin C sodium; Acidification; China 展开更多
关键词 vitamin c vitamin c sodium AcIDIFIcATION china
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烹调炊具及盐对蔬菜中Vitamin C含量的影响 被引量:3
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作者 刘洋 张海霞 +3 位作者 饶志涛 高鹏 潘敏 王丹 《同济大学学报(医学版)》 CAS 2002年第3期210-212,共3页
目的 了解家庭烹饪条件下铁锅、铝锅、不锈钢锅、不粘锅及无碘盐对蔬菜中VitaminC(VC)含量的影响。方法 用四种锅烹调经整理、洗切、称重后的蔬菜样品 ,严格控制加盐和其他烹饪条件 ,用 2 ,4-二硝基苯肼法测定样品中VC 含量。结果 ... 目的 了解家庭烹饪条件下铁锅、铝锅、不锈钢锅、不粘锅及无碘盐对蔬菜中VitaminC(VC)含量的影响。方法 用四种锅烹调经整理、洗切、称重后的蔬菜样品 ,严格控制加盐和其他烹饪条件 ,用 2 ,4-二硝基苯肼法测定样品中VC 含量。结果 大部分蔬菜经烹调后VC 含量减少 ;不粘锅保存率较高 ,铁锅、铝锅、不锈钢锅的保存率高低与蔬菜品种有关 ;先加盐较后加盐对蔬菜中VC 的损失大。 展开更多
关键词 炊具 蔬菜 维生素c 食物营养 营养分析
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Impact of poly chlorinated biphenyl (Aroclor 1254) and vitamin C on antioxidant system of rat ventral prostate 被引量:5
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作者 M. Sridhar P. Venkataraman +4 位作者 S. Dhanammal A. Arunkumar M.M. Aruldhas N. Srinivasan J. Arunakaran 《Asian Journal of Andrology》 SCIE CAS CSCD 2004年第1期19-22,共4页
Aim: To evaluate the effect of polychlorinated biphenyls (PCB) and vitamin C on ventral prostatic antioxidant system in adult male rats. Methods: A group of 20 adult male rats were administered ip Aroclor 1254 in corn... Aim: To evaluate the effect of polychlorinated biphenyls (PCB) and vitamin C on ventral prostatic antioxidant system in adult male rats. Methods: A group of 20 adult male rats were administered ip Aroclor 1254 in corn oil at a dose of 2 mg·kg-1·day-1 for 30 days. Ten control rats were administered only the vehicle. After 30 days the treated rats were divided at random into 2 sub-groups of 10 animals each. One sub-group received vitamin C at a dose of 500 mg·kg-1·day-1 for 10 days. The other group was maintained as Aroclor 1254 control. Twenty-four hours after the last treatment the rats were killed by decapitation. Ventral prostatic homogenate was prepared and used for the estimation of enzymatic antioxidants, including superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) and hydrogen peroxide (H2O2), lipid peroxidation (LPO) and prostatic acid phosphatase. The serum levels of total T3, total T4, TSH, testosterone and estradiol were also assayed. Results: The body weight and ventral prostatic weight were reduced in PCB treated rats. The activities of SOD, CAT, GST and acid phosphatase were decreased while the levels of H2O2 and lipid peroxidation were increased in the ventral prostate of PCB treated rats. Administration of vitamin C restored these parameters. Serum levels of thyroid hormones, estradiol and testosterone were decreased in PCB treated animals. Administration of vitamin C restored the thyroid hormone levels. Conclusion: PCB induces oxidative stress and decreases the antioxidant enzymes in the ventral prostate of adult male rats; the effects could be reversed by the administration of vitamin C. 展开更多
关键词 polychlorinated biphenyls Aroclor 1254 ventral prostate ANTIOXIDANTS lipid peroxidation thyroid hormone vitamin c
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Crystallization Thermodynamic and Kinetic Behaviors of Vitamin C in Batch Crystallizer 被引量:7
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作者 陈慧萍 王静康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2000年第2期95-99,共5页
The bench-scale cooling crystallization for ternary solution of L-ascorbic acid (Vitamin C) was studied.The solid-liquid phase diagram of Vitamin C-water-ethanol system was obtained on the basis of differential scanni... The bench-scale cooling crystallization for ternary solution of L-ascorbic acid (Vitamin C) was studied.The solid-liquid phase diagram of Vitamin C-water-ethanol system was obtained on the basis of differential scanning calorimeter (DSC) curves. The heat of crystallization of Vitamin C was calculated with the aid of quantitative analysis. According to the population balance equation under unsteady state, the rates of nucleation and growth were determined. The parameters of crystallization kinetics equations were estimated by regression of experimental data. Crystal morphology and size were determined with x-ray diffraction and TA Ⅱ Coulter Counter. 展开更多
关键词 vitamin c cRYSTALLIZATION THERMODYNAMIcS DSc kinetics
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Lipophilic Enhance of Vitamin C Protective Activity Against Free-radical-induced Damage in vivo 被引量:5
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作者 LUOXu-yang LIUZai-qun +3 位作者 SUNYun-xiu SUIDa-yuan YUXiao-feng QUShao-chun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第4期428-431,共4页
A group of experimental rats under free radical damage are given various amounts of a lipophilic vitamin C(ascorbyl-6-laurate, VC-12), and its parent compound, vitamin C, respectively. It has been found that the effec... A group of experimental rats under free radical damage are given various amounts of a lipophilic vitamin C(ascorbyl-6-laurate, VC-12), and its parent compound, vitamin C, respectively. It has been found that the effects of 1 12 mmol/kg VC-12 on decreasing triglyceride(TG), total cholesterol(TC), low density lipoprotein cholesterol (LDL-c) and lipid peroxide(LPO), and increasing high density lipoprotein cholesterol(HDL-c) and superoxide dismutase(SOD) are similar to those of 2 27 mmol/kg vitamin C. In addition, VC-12(1 12 mmol/kg) can increase the prostacycline(PGI 2) and decrease the thromboxane(TXA 2) even better than vitamin C(2 27 mmol/kg). The above facts demonstrate that the antioxidative activity of VC-12 is higher than twice that of vitamin C. So, ascorbyl-6-laurate may be a novel antioxidant drug against free radical damage. 展开更多
关键词 ANTIOXIDANT Free radical Ascorbyl-6-laurate vitamin c Blood lipid metabolism in vivo
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Preventive and Therapeutic Potential of Vitamin C in Mental Disorders 被引量:6
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作者 Qian-qian HAN Tian-tian SHEN +2 位作者 Fang WANG Peng-fei WU Jian-guo CHEN 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2018年第1期1-10,共10页
In this review,we summarize the involvement of vitamin C in mental disorders by presenting available evidence on its pharmacological effects in animal models as well as in clinical studies.Vitamin C,especially its red... In this review,we summarize the involvement of vitamin C in mental disorders by presenting available evidence on its pharmacological effects in animal models as well as in clinical studies.Vitamin C,especially its reduced form,has gained interest for its multiple functions in various tissues and organs,including central nervous system(CNS).Vitamin C protects the neuron against oxidative stress,alleviates inflammation,regulates the neurotransmission,affects neuronal development and controls epigenetic function.All of these processes are closely associated with psychopathology.In the past few decades,scientists have revealed that the deficiency of vitamin C may lead to motor deficit,cognitive impairment and aberrant behaviors,whereas supplement of vitamin C has a potential preventive and therapeutic effect on mental illness,such as major depressive disorder(MDD),schizophrenia,anxiety and Alzheimer's disease(AD).Although several studies support a possible role of vitamin C against mental disorders,more researches are essential to accelerate the knowledge and investigate the mechanism in this field. 展开更多
关键词 vitamin c ascorbic acid oxidative stress Alzheimer's disease major depressivedisorder
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Thermal Analysis of Vitamin C Affecting Low.temperature Oxidation of Coal 被引量:3
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作者 秦波涛 窦国兰 WANG Deming 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第3期519-522,共4页
Simultaneous thermal analysis was used to study the influence of Vitamin C as possible chemical additive inhibiting coal oxidation process at low temperature. Some oxidation characteristics of Vitamin C affecting the ... Simultaneous thermal analysis was used to study the influence of Vitamin C as possible chemical additive inhibiting coal oxidation process at low temperature. Some oxidation characteristics of Vitamin C affecting the coal oxidation were investigated at different heating rates. The TG-DSC data show that the impact of Vitamin C on coal oxidation process can be directly evaluated using ignition temperature and critical temperature. Comparison with the effect of water on coal oxidation shows that Vitamin C is more efficient than water. However, the blank experiment conducted with inert a-Al2O3 also suggests that Vitamin C can decompose at about 200 ℃, which limits the usage of Vitamin C on inhibiting coal oxidation. 展开更多
关键词 thermal analysis vitamin c coal oxidation INHIBITOR
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Effect of dietary supplementation of vitamin C on growth, reactive oxygen species, and antioxidant enzyme activity of Apostichopus japonicus(Selenka) juveniles exposed to nitrite 被引量:4
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作者 骆作勇 王宝杰 +3 位作者 刘梅 蒋克勇 刘明星 王雷 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期749-763,共15页
Different amounts of vitamin C were added to diets fed to juveniles (2.5+0.15 g) of sea cucumber Apostichopus japonicus (Selenka) in an attempt to reduce the stress response of specimens exposed to nitrite stress... Different amounts of vitamin C were added to diets fed to juveniles (2.5+0.15 g) of sea cucumber Apostichopus japonicus (Selenka) in an attempt to reduce the stress response of specimens exposed to nitrite stress. A commercial feed was used as the control diet and three experimental diets were made by supplementing 1 000, 1 500, or 2 000 mg vitamin C/kg diet to control diet separately in a 45-day experiment. Sea cucumbers were exposed to three different levels (0.5, 1.0, and 1.5 mg/L) of nitrite stress for 4, 8, and 12 h at four time intervals (0, 15, 30, and 45 d). Growth of the animals was recorded during the experiment. Reactive oxygen species (ROS) (i.e. hydroxyl free radical (-OH), malondialdehyde (MDA) and total antioxidant capacity (T-AOC)) and antioxidant enzyme activities (i.e., superoxide dismutase (SOD) and eatalase (CAT)) were measured. Response surface methodology (RSM) was used to analyze the effect of multiple factors on ROS indices and enzyme activities. Weight gain (WG) and special growth rate (SGR) of vitamin C supplementation groups were significantly higher than those of control group (P〈0.05). The levels of-OH and MDA increased under exposure time extending and nitrite concentration increasing, whereas T-AOC level decreased. SOD and CAT activities increased at 4 h and 8 h and decreased at 12 h. During the days in which the animal consumed experimental diets, the levels of-OH and MDA decreased and that of T-AOC increased. This result suggests that diets containing vitamin C could reduce the nitrite stress response in the animals and increase their antioxidant capacity. The multifactor regression equation of growth performance, ROS indices, and duration of feeding results suggest that vitamin C supplementation of 1 400-2 000 mg/kg diet for 29-35 days could reduce effectively the effects of nitrite exposure. 展开更多
关键词 sea cucumber Apostichopus japonicus Selenka vitamin c nitrite stress antioxidant enzyme reactive oxygen species (ROS) response surface methodology (RSM)
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First-order Derivative Spectrophotometry for the Determination of Vitamin C in Medicament 被引量:3
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作者 MENG Qing-fan TENG Le-sheng JIANG Chao-jun An Jin-shuang LI Lei LU Jia-hui TENG Li-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第1期29-31,共3页
A novel method for the determination of vitamin C(Vc) is proposed in this article. After the reaction with Folin-Ciocalteau reagent at ambient temperature, Vc solution was scanned at 750--1100 nm, and its first-orde... A novel method for the determination of vitamin C(Vc) is proposed in this article. After the reaction with Folin-Ciocalteau reagent at ambient temperature, Vc solution was scanned at 750--1100 nm, and its first-order derivative spectrum were obtained from the original spectrum. The values of derivative selected at 995 nm were used for determination. It was proved that Vc could quickly react with Folin-Ciocalteau reagent within 5 min and the product was quite stable for a long time. The conditions required for this method is not very complicated, its precision and accuracy are similar to those of the iodometric titration described in Chinese Pharmacopoeia, and the limit of detection is 0.312 μg/mL. The determination of the results of vitamin C tablet, pill, and injection demonstrates that this method has wide pharmaceutical applications. 展开更多
关键词 First-order derivative spectroscopy vitamin c determination Folin-ciocalteau regent
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Does vitamin C have the ability to augment the therapeutic effect of bone marrow-derived mesenchymal stem cells on spinal cord injury? 被引量:2
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作者 Nesrine Salem Mohamed Y.Salem +7 位作者 Mohammed M.Elmaghrabi Moataz A.Elawady Mona A.Elawady Dina Sabry Ashraf Shamaa Abdel-Haleem H.Elkasapy Noha Ibrhim Azza Elamir 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第12期2050-2058,共9页
Methylprednisolone(MP) is currently the only drug confirmed to exhibit a neuroprotective effect on acute spinal cord injury(SCI). Vitamin C(VC) is a natural water-soluble antioxidant that exerts neuroprotective ... Methylprednisolone(MP) is currently the only drug confirmed to exhibit a neuroprotective effect on acute spinal cord injury(SCI). Vitamin C(VC) is a natural water-soluble antioxidant that exerts neuroprotective effects through eliminating free radical damage to nerve cells. Bone marrow mesenchymal stem cells(BMMSCs), as multipotent stem cells, are promising candidates in SCI repair. To evaluate the therapeutic effects of MP, VC and BMMSCs on traumatic SCI, 80 adult male rats were randomly divided into seven groups: control, SCI(SCI induction by weight-drop method), MP(SCI induction, followed by administration of 30 mg/kg MP via the tail vein, once every other 6 hours, for five times), VC(SCI induction, followed by intraperitoneal administration of 100 mg/kg VC once a day, for 28 days), MP + VC(SCI induction, followed by administration of MP and VC as the former), BMMSCs(SCI induction, followed by injection of 3 × 10~6 BMMSCs at the injury site), and BMMSCs + VC(SCI induction, followed by BMMSCs injection and VC administration as the former). Locomotor recovery was assessed using the Basso Mouse Scale. Injured spinal cord tissue was evaluated using hematoxylin-eosin staining and immunohistochemical staining. Expression of transforming growth factor-beta, tumor necrosis factor-alpha, and matrix metalloproteinase-2 genes was determined using real-time quantitative PCR. BMMSCs intervention better promoted recovery of nerve function of rats with SCI, mitigated nerve cell damage, and decreased expression of transforming growth factor-beta, tumor necrosis factor-alpha, and matrix metalloproteinase-2 genes than MP and/or VC. More importantly, BMMSCs in combination with VC induced more obvious improvements. These results suggest that VC can enhance the neuroprotective effects of BMMSCs against SCI. 展开更多
关键词 nerve regeneration spinal cord injury vitamin c METHYLPREDNISOLONE bone marrow mesenchymalstern cells locotmotor neural regeneration
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Effects of Combined Instantaneous High-Pressure and MediumTemperature on the Retention of Total Vitamin Cin Wax Gourd Juices 被引量:2
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作者 LIUJin-jie WANGWu +2 位作者 ZHANGLi HEJing-min CHENCong-gui 《Agricultural Sciences in China》 CAS CSCD 2003年第8期919-923,共5页
Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juic... Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juices were investigated under 20 - 80 MPa, 35 - 58℃, pH 3. 0 - 6. 0 and processing time 0-8 min. Results showed that the loss of Vc increased with elevated processing temperatures(50 MPa, 4 min). When the temperature of raw juices was 35℃, the retention of total Vc was higher under 40 - 60 MPa than that under the pressure < 40 MPa or > 60 MPa, and it was up to 94%(4 min). The retention of total Vc decreases slowly within 6 min, but rapidly after 6 min. The pH can also influence the retention of total Vc, and this retention can come to a highest point at pH 6.0. 展开更多
关键词 Instantaneous high-pressure Medium temperature combined process vitamin c RETENTION
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Enzyme-catalyzed Transesterification of Unusual Substrate: Synthesis of Acyclovir and L-ascorbic Acid (Vitamin C) Vinyl Esters 被引量:1
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作者 Xing Tao XUE De Shui Lu +3 位作者 Zhi Chun CHEN Qi WU Ying CAI Xian Fu LIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期163-166,共4页
The synthesis of acyclovir and L-ascorbic acid with divinyladipate was performed with alkaline protease from Bacillus subtilis and lipase from Lipozyme (immobilized from Mucor miehei) in different anhydrous organic so... The synthesis of acyclovir and L-ascorbic acid with divinyladipate was performed with alkaline protease from Bacillus subtilis and lipase from Lipozyme (immobilized from Mucor miehei) in different anhydrous organic solvents. Two corresponding derivatives were obtained. 展开更多
关键词 Alkaline protease LIPASE TRANSESTERIFIcATION AcYcLOVIR vitamin c vinyl ester.
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