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Interaction between inflammatory bowel disease,physical activity,and myokines:Assessment of serum irisin levels 被引量:1
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作者 Marwan SM Al-Nimer 《World Journal of Gastroenterology》 SCIE CAS 2024年第22期2923-2926,共4页
Inflammatory bowel disease(IBD),including Crohn’s disease and ulcerative colitis,showed a wide spectrum of intestinal and extra-intestinal manifestations,which rendered the patients physically inactive and impaired t... Inflammatory bowel disease(IBD),including Crohn’s disease and ulcerative colitis,showed a wide spectrum of intestinal and extra-intestinal manifestations,which rendered the patients physically inactive and impaired their quality of life.It has been found that physical activity is a non-pharmacological intervention that improves the quality of life for those patients.Irisin is one member of the myokines secreted by muscle contraction during exercise and could be used as an antiinflammatory biomarker in assessing the physical activity of IBD patients.In addition,experimental studies showed that exogenous irisin significantly decreased the inflammatory markers and the histological changes of the intestinal mucosa observed in experimental colitis.Furthermore,irisin produces changes in the diversity of the microbiota.Therefore,endogenous or exogenous irisin,via its anti-inflammatory effects,will improve the health of IBD patients and will limit the barriers to physical activity in patients with IBD. 展开更多
关键词 Irisin Inflammatory bowel disease Physical activity MYOKINES Prognostic marker
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Shifting the Paradigm:A Fresh Look at Physical Activity Frequency and Its Impact on Mental Health,Life Satisfaction,and Self-Rated Health in Adolescents 被引量:1
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作者 Wenjie Li Yucheng Gao +3 位作者 Guoqing Liu Rongkai Hao Meijie Zhang Xiaotian Li 《International Journal of Mental Health Promotion》 2024年第2期83-92,共10页
As adolescent mental health problems are becoming a more serious issue globally,this paper explores the relationship of physical activity in adolescents and its frequency on mental health as well as examines the media... As adolescent mental health problems are becoming a more serious issue globally,this paper explores the relationship of physical activity in adolescents and its frequency on mental health as well as examines the mediating effects of life satisfaction and self-rated health in order to provide a reference for the promotion of mental health in adolescents.A sample of 3578 Chinese high school students completed questionnaires assessing their mental health,physical activity frequency,life satisfaction,and self-rated health.The mean SCL-90 value for adolescents was found to be 1.629%,and 24.73%of adolescents had varying degrees of mental health issue.Increased physical activity frequency is positively associated with improved mental health(p<0.001).Additionally,life satisfaction and self-rated health were found to play significant mediating roles in the relationship between physical activity frequency and mental health.Specifically,low-frequency physical activity had the most pronounced mediating effect on mental health through life satisfaction,while high-frequency physical activity exerted the most significant mediating effect on mental health through self-rated health.These findings underscore the importance of promoting physical activity among adolescents and highlight the distinct pathways through which physical activity frequency can influence mental health outcomes.Further research is needed to explore these relationships in diverse populations and settings,as well as to develop targeted intervention. 展开更多
关键词 Adolescents physical activity mental health life satisfaction self-rated health
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Maillard reaction affecting immunobinding activity and digestibility of tropomyosin in Alectryonella plicatula food matrix
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作者 Chenchen Yu Xinrong He +7 位作者 Nairu Ji Shuai Kang Dongxiao Li Huilin Zhang Yang Yang Dong Lai Qingmei Liu Guangming Liu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2959-2969,共11页
In recent years,the allergy rate of oysters has surged,and daily food processing methods make it hard to reduce heat resistance and digestive allergy such as tropomyosin(TM).In this study,the Maillard reaction with xy... In recent years,the allergy rate of oysters has surged,and daily food processing methods make it hard to reduce heat resistance and digestive allergy such as tropomyosin(TM).In this study,the Maillard reaction with xylose significantly reduced the IgE binding capacity of Alectryonella plicatula food matrix(AFM),that reduced by(77.81±2.68)%.The study found the Maillard reaction changes the structure of the AFM,in which the content ofα-helix decreased by(24.64±1.46)%.Structural transformation further explains why the Maillard reaction alters the immunobinding activity of AFM.In addition,the Maillard reaction reduces the digestive stability of the AFM and makes TM in the A.plicatula food matrix Maillard reaction products(AFM-MRPs)more easily digested.Based on the above research,10 amino acids on the 7 IgE epitopes of TM were modified.This result indicates that the Maillard reaction reduces the immunobinding activity of the AFM by changing the structure and modifying the amino acids on the epitope. 展开更多
关键词 Alectryonella plicatula Food matrix Immunobinding activity Maillard reaction TROPOMYOSIN
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Activity Data and Emission Factor for Forestry and Other Land Use Change Subsector to Enhance Carbon Market Policy and Action in Malawi
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作者 Edward Missanjo Henry Kadzuwa 《Journal of Environmental Protection》 2024年第4期401-414,共14页
Activity data and emission factors are critical for estimating greenhouse gas emissions and devising effective climate change mitigation strategies. This study developed the activity data and emission factor in the Fo... Activity data and emission factors are critical for estimating greenhouse gas emissions and devising effective climate change mitigation strategies. This study developed the activity data and emission factor in the Forestry and Other Land Use Change (FOLU) subsector in Malawi. The results indicate that “forestland to cropland,” and “wetland to cropland,” were the major land use changes from the year 2000 to the year 2022. The forestland steadily declined at a rate of 13,591 ha (0.5%) per annum. Similarly, grassland declined at the rate of 1651 ha (0.5%) per annum. On the other hand, cropland, wetland, and settlements steadily increased at the rate of 8228 ha (0.14%);5257 ha (0.17%);and 1941 ha (8.1%) per annum, respectively. Furthermore, the results indicate that the “grassland to forestland” changes were higher than the “forestland to grassland” changes, suggesting that forest regrowth was occurring. On the emission factor, the results interestingly indicate that there was a significant increase in carbon sequestration in the FOLU subsector from the year 2011 to 2022. Carbon sequestration increased annually by 13.66 ± 0.17 tCO<sub>2</sub> e/ha/yr (4.6%), with an uncertainty of 2.44%. Therefore, it can be concluded that there is potential for a Carbon market in Malawi. 展开更多
关键词 activity Data Emission Factor Climate Change Forestland Carbon Market
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Deciphering the linear relationship in the activity of the oxygen reduction reaction on Pt electrodes:A decisive role of adsorbates
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作者 Haowen Cui Yan-Xia Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期70-77,共8页
Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte s... Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte solution cannot be ignored.Consequently,we have systematically investigated the impact of adsorbate species and concentration,as well as solution pH,on the ORR activity on Pt(111)and Pt(poly)electrodes.The results all tend to establish a linear quantitative relationship between the onset potential for ORR and the adsorption equilibrium potential of the adsorbate.This finding indicates the decisive role of adsorbates in the onset potential for ORR,suggesting that the adsorption potential of adsorbates can serve as an intuitive criterion for ORR activity.Additional support for this conclusion is derived from experimental results obtained from the oxygen evolution reaction on Pt(poly)with different adsorbate species and from the hydrogen evolution reaction on Pt(111)with iodine adsorption.We further propose both an empirical equation for the onset potential for ORR and the concept of a potential-regulated adsor-bate shielding effect to elucidate the influence of adsorbates on ORR activity.This study provides new insights into the high onset overpotential of the ORR and offers potential strategies for predicting and enhancingORRactivity inthefuture. 展开更多
关键词 Oxygen reduction reaction activity ADSORBATE Equilibrium potential Pt(111)
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Unveiling the geometric site dependent activity of spinel Co_(3)O_(4)for electrocatalytic chlorine evolution reaction
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作者 Linke Cai Yao Liu +5 位作者 Jingfang Zhang Qiqi Jia Jiacheng Guan Hongwei Sun Yu Yu Yi Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期95-103,共9页
Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catal... Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catalytic contribution of geometric Co site in the electrocatalytic CER plays a pivotal role to precisely modulate electronic configuration of active Co sites to boost CER.Herein,combining density functional theory calculations and experiment results assisted with operando analysis,we found that the Co_(Oh) site acts as the main active site for CER in spinel Co_(3)O_(4),which shows better Cl^(-)adsorption and more moderate intermediate adsorption toward CER than CoTd site,and does not undergo redox transition under CER condition at applied potentials.Guided by above findings,the oxygen vacancies were further introduced into the Co_(3)O_(4) to precisely manipulate the electronic configuration of Co_(Oh) to boost Cl^(-)adsorption and optimize the reaction path of CER and thus to enhance the intrinsic CER activity significantly.Our work figures out the importance of geometric configuration dependent CER activity,shedding light on the rational design of advanced electrocatalysts from geometric configuration optimization at the atomic level. 展开更多
关键词 Chlorine evolution reaction Geometry effects Active chlorine Electronic configuration optimization Spinel oxides
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Screening for Anti-tumor Activity of Fractions from Buddleja officinalis Maxim
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作者 Tong LI Xin XIE +9 位作者 Liyuan LI Aipeng LI Zhidong LEI Tingting HE Sirui MO Shangfeng HUANG Yao LIN Suoyi HUANG Lixiang LU Shiyou ZHOU 《Medicinal Plant》 2024年第2期48-50,56,共4页
[Objectives]The anti-tumor activity of fractions from Buddleja officinalis Maxim.by petroleum ether,ethyl acetate,n-butanol and water solvent was studied.[Methods]The ethanol extract from B.officinalis Maxim.was extra... [Objectives]The anti-tumor activity of fractions from Buddleja officinalis Maxim.by petroleum ether,ethyl acetate,n-butanol and water solvent was studied.[Methods]The ethanol extract from B.officinalis Maxim.was extracted and then concentrated with petroleum ether,ethyl acetate,n-butanol and water,respectively,and the extracts were obtained.The inhibitory effects of the four different fractions on the growth of three tumor cell lines in vitro were detected by CCK-8 method,and the median inhibitory concentration(IC 50 value)was calculated.[Results]The four fractions inhibited the growth of the three tumor cell lines in vitro,among which the n-butanol fraction had the best anti-tumor activity.The IC 50 values of the n-butanol fraction on human gastric cancer(SGC-7901),human breast cancer(MCF-7)and human liver cancer(BEL-7404)cell lines were 0.08,1.58 and 0.12 mg/mL,respectively.[Conclusions]Petroleum ether,ethyl acetate,n-butanol and water fractions from the ethanol extract of B.officinalis Maxim.had certain anti-tumor effects,and the n-butanol fraction had the best anti-tumor activity. 展开更多
关键词 Buddleja officinalis Maxim. Tumor cells ANTI-TUMOR activity screening
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Glutamatergic CYLD deletion leads to aberrant excitatory activity in the basolateral amygdala:association with enhanced cued fear expression
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作者 Huidong Li Faqin Li +8 位作者 Zhaoyi Chen Erwen Wu Xiaoxi Dai Danni Li Haojie An Shiyi Zeng Chunyan Wang Li Yang Cheng Long 《Neural Regeneration Research》 SCIE CAS 2025年第11期3259-3272,共14页
Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-... Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B pathway.CYLD is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly expressed.Emerging studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like behaviors.However,the precise role of CYLD in glutamatergic neurons is largely unknown.Here,we first proposed involvement of CYLD in cued fear expression.We next constructed transgenic model mice with specific deletion of Cyld from glutamatergic neurons.Our results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male mice.Further,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male mice.Altogether,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial activation.This may contribute,at least in part,to cued fear expression. 展开更多
关键词 basolateral amygdala cued fear expression cylindromatosis deubiquitinase glutamate receptor 1 glutamatergic neuron microglial activation N-methyl-D-aspartate receptor 1 neuronal activation synaptic transmission
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Ultrasonic-Assisted Extraction of Fucoxanthin from Marine Macroalga Padina australis:Optimization,Bioactivity,and Structural Characterization
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作者 L.Antony Catherine Flora Kirubanandan Shanmugam Renganathan Sahadevan 《Proceedings of Anticancer Research》 2024年第5期89-104,共16页
Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the caroten... Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the carotenoid family,fucoxanthin plays a crucial role in both the food and pharmaceutical industries.This research explores the effects of ultrasonics on the extraction of fucoxanthin from the marine macroalga Padina australis.In addition,various extraction techniques and the influence of solvents on the efficient separation of fucoxanthin from algae have been studied and compared.Using methanol,chloroform,and a combination of methanol and chloroform(1:1,v/v),conventional fucoxanthin extraction from Padina australis yielded 8.12 mg of fucoxanthin per gram of biomass.However,the ultrasonic-assisted extraction resulted in a significantly higher yield of 16.9 mg of fucoxanthin per gram of biomass,demonstrating that the use of ultrasonics enhances the extraction rate compared to conventional methods.Therefore,the efficient separation of fucoxanthin from Padina australis is highly dependent on ultrasonic-assisted extraction.The process conditions for the extraction were optimized to maximize the yield of fucoxanthin from seaweeds.The following parameters were selected for optimization studies:moisture content,particle size,mixing speed,extraction temperature,extraction duration,and solid-to-solvent ratio.The extracted fucoxanthin exhibited various biological activities,including antimicrobial and antioxidant properties,and its structure was elucidated through FTIR and NMR spectroscopy.Additionally,thin-layer chromatography of the crude algae extracts confirmed the presence of fucoxanthin in the marine algae.Given these findings,the optimized extraction process holds the potential for scaling up to large-scale fucoxanthin production.Fucoxanthin,as a potent pharmacological agent,offers promising applications in the treatment of various ailments. 展开更多
关键词 Marine algae FUCOXANTHIN ULTRASONICS Extraction OPTIMIZATION TLC DPPH Antimicrobial antioxidant activities
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Passive activity enhances residual control ability in patients with complete spinal cord injury
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作者 Yanqing Xiao Mingming Gao +6 位作者 Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2337-2347,共11页
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these... Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury. 展开更多
关键词 complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task
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Research on Extraction of Anti-allergic Active Ingredient from Citrus Peels and Its Anti-allergic Activity
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作者 金慧伟 芮昶 +3 位作者 关荣发 何怡 刘光富 赵进 《Agricultural Science & Technology》 CAS 2012年第3期529-532,共4页
[Objective] This study aimed to determine the optimal process conditions for extraction of anti-allergic active ingredient from citrus peels. [Method] Crude anti- allergic active extracts of citrus peels were extracte... [Objective] This study aimed to determine the optimal process conditions for extraction of anti-allergic active ingredient from citrus peels. [Method] Crude anti- allergic active extracts of citrus peels were extracted. Effects of extraction conditions including extraction temperature, ethanol concentration, extraction time and liquid-to-solid ratio on extraction were explored with single-factor experiment, and the extrac- tion process was optimized with orthogonal experiment. [Result] Based on the single- factor experiment and orthogonal experiment, the optimal extraction condition for crude anti-allergic active extracts of citrus peels were determined to be under extraction temperature of 60℃, ethanol concentration of 70%, extraction time of 60 min, liquid-to-solid ratio of 1:25 and twice extraction. [Concluslon] This process condition is of simple operation and high extraction efficiency, which is environment-friendly and suitable for the extraction of crude anti-allergic active extracts from citrus peels. This study provided a new approach and research ideas for the effective and rapid extraction of anti-allergic active ingredient in citrus peels. 展开更多
关键词 Citrus peel Anti-allergic active ingredient EXTRaction
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Study on Extraction and Catalytic Activity of Tyrosinase
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作者 王宁芳 《Agricultural Science & Technology》 CAS 2016年第12期2893-2895,共3页
Objective] Tyrosinase is a kind of polyphenol oxidase used widely, and the study of tyrosinase attracts extensive attention. [Method] ln this experiment, A conversion kinetic curve of dopa solution was obtained using ... Objective] Tyrosinase is a kind of polyphenol oxidase used widely, and the study of tyrosinase attracts extensive attention. [Method] ln this experiment, A conversion kinetic curve of dopa solution was obtained using absorbance of potato extract at 480 nm in Na2HPO4-HCl buffer system at a pH value of 7.2 with the vari-ation rate of absorbance against time (ΔA/Δt) as reaction rate, and the activity of tyrosinase could thus be calculated. [Result] The results showed that at the wave-length, in the Na2HPO4-HCl buffer system with a pH value at 7.2, there was little in-terference to the system, the data showed smal fluctuations, and the activity of ty-rosinase was high and stable, further providing a theoretical foundation for the de-termination and study of factors influencing tyrosinase activity. [Conclusion] The catalytic activity of tyrosinase was studied and determined with buffer solution as substrate with high accuracy and good effect. 展开更多
关键词 ABSORBANCE Kinetic curve TYROSINASE activity
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Chemical composition, mechanism of antibacterial action and antioxidant activity of leaf essential oil of Forsythia koreana deciduous shrub 被引量:15
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作者 Xiao-Nan Yang Imran Khan Sun Chul Kang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第9期682-688,共7页
Objective: To identify the chemical constituents of leaf essential oil of Forsythia koreana(F. koreana) and evaluate its ef ects on bacterial strains. Methods: The essential oil of leaf of F. koreana was extracted by ... Objective: To identify the chemical constituents of leaf essential oil of Forsythia koreana(F. koreana) and evaluate its ef ects on bacterial strains. Methods: The essential oil of leaf of F. koreana was extracted by using hydrodistillation process and the volatile components investigated with the help of gas chromatography coupled with mass spectrometry. The antibacterial study was carried out with the help of agar disc dif usion method, MIC, MBC and viable count. The mode of action was determined with help of potassium ion l ux, cellular material release and scanning electron microscopy. The antioxidant activity was determined with the help of 2, 3-diphenyl-2-picrylhydrazyl method, nitric oxide scavenging activity and superoxide anion radical scavenging assay. Results: Total ten compounds were identii ed as trans-phytol(42.73%), cis-3-hexenol(12.95%), 毬-linalool(10.68%), trans-2-hexenal(8.86%), trans-2-hexenol(8.86%), myrcenol(3.86%), 4-vinylphenyl acetate(3.86%),(4Z)-4,6-heptadien-1-ol(3.18%), lemonol(2.73%) and benzeneacetaldehyde(2.27%) by gas chromatography coupled with mass spectrometry. The antibacterial study was demonstrated that leaf essential oil of F. koreana act against foodborne and other pathogenic bacteria. The mode of action revealed that this essential oil acted on the cytoplasmic membrane, resulting in loss of integrity and increased permeability. In addition, leaf essential oil of F. koreana was shown to be rich in linalool, which contributes to improved antioxidant activity. Conclusions: These results show that leaf essential oil of F. koreana has great potential as a natural food preservative, antibacterial and antioxidant agent. 展开更多
关键词 ANTIBACTERIAL activity Antioxidant activity Cell material RELEASED Essential oil GC-MS Potassium ion flux
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Pedalium murex Linn(Pedaliaceae) fruits:a comparative antioxidant activity of its different fractions 被引量:12
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作者 DK Patel R Kumar +1 位作者 SK Prasad S Hemalatha 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第5期395-400,共6页
Objective:To examine the antioxidant activity and total phenolic content of different solvent fractions of Pedulium murex(P.murex)Linn fruits(Family:Pedaliaceae)as well as the correlation between the total antioxidant... Objective:To examine the antioxidant activity and total phenolic content of different solvent fractions of Pedulium murex(P.murex)Linn fruits(Family:Pedaliaceae)as well as the correlation between the total antioxidant capacity and total phenolic content.Methods:In the present study,the antioxidant activities of P.murex were evaluated using six in-vitro assays,namely total antioxidant assay,DPPH assay,reducing power,nitric oxide scavenging,hydrogen peroxide scavenging and deoxyribose scavenging assays,and total phenol contents were also investigated.Results:The ethyl acetate(EA)fraction was found to have high levels of phenolic content(298.72±2.09 mg GAE/g).The EA fraction exhibit higher total antioxidant capacity,higher percentage of DPPH radical scavenging activity(135.11±2.95μg/mL),nitric oxide(200.57±4.5lμg/mL),hydrogen peroxide(2I7.91±6.12μg/mL),deoxyribose(250.01±4.68μg/mL)and higher reducing power.Correlation coefficient(r^2=0.914)was found to be significant between total phenolic content and total antioxidant activity.Conclusions:In general,the results indicate that the EA fractions are rich in phenolic antioxidants with potent free radical scavenging activity implying their importance to human health. 展开更多
关键词 Pedalium murex Antioxidant activity Total phenolics DIFFERENT solvent fraction In VITRO assay SCAVENGING activity
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Biological Mode of Action of Dimethomorph on Pseudoperonospora cubensis and Its Systemic Activity in Cucumber 被引量:6
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作者 WANG Han-cheng ZHOU Ming-guo WANG Jian-xin CHEN Chang-jun LI Hong-xia SUN Hai-yan 《Agricultural Sciences in China》 CAS CSCD 2009年第2期172-181,共10页
Dimethomorph is a fungicide with high activity against Peronosporomycetes plant pathogens. The present study showed that dimethomorph is effective on controlling the oomycete fungal pathogen Pseudoperonospora cubensis... Dimethomorph is a fungicide with high activity against Peronosporomycetes plant pathogens. The present study showed that dimethomorph is effective on controlling the oomycete fungal pathogen Pseudoperonospora cubensis causing downy mildew on cucumber. The fungicide did not affect zoospores discharge from sporangia of P. cubensis, but it strongly inhibited mycelial growth and sporangial production in vitro and increased lysis of zoospores. Dose of 2 mg L^-1 of dimethomorph was sufficient to inhibit mycelial growth and sporangial production of P. cubensis on leaf disks, 5 mg L^-1 was enough to lyse zoospores of P. cubensis, and 25 mg L^-1 was required to inhibit sporangial production on detached leaves. In whole plant tests, dimethomorph exhibited strong protective and curative activity. Dimethomorph when applied at a dose of 300 mg L^-1 for 1, 3, 5, 7 days before inoculation exhibited 100% efficacy on disease control. On the other hand, efficacies of 67.1 and 31.5% were obtained when the same dose of dimethomorph was applied for 1 and 3 days after inoculation, respectively. So dimethomorph had persistence effect on leaves for 7 days at least and exhibited strong protective and curative activity. Bioassay analyses showed that dimethomorph could be translocated in the xylem system, redistributed in the leaf, and penetrated from the upper surface to the lower surface of the leaf but could not be translocated in phloem system or transferred from the roots to leaves of cucumber plants in sufficient amounts for disease control. The biocharacteristics of dimethomorph make it well suitable for integration of a control programme against downy mildew disease on cucumber and as a component to delay other peronosporomycetes fungicide-resistance development. 展开更多
关键词 biological activity DIMETHOMORPH Pseudoperonospora cubensis systemic activity
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Antimicrobial peptides: mechanism of action, activity and clinical potential 被引量:3
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作者 Qi-Yu Zhang Zhi-Bin Yan +7 位作者 Yue-Ming Meng Xiang-Yu Hong Gang Shao Jun-Jie Ma Xu-Rui Cheng Jun Liu Jian Kang Cai-Yun Fu 《Military Medical Research》 SCIE CSCD 2022年第2期231-258,共28页
The management of bacterial infections is becoming a major clinical challenge due to the rapid evolution of antibiotic resistant bacteria.As an excellent candidate to overcome antibiotic resistance,antimicrobial pepti... The management of bacterial infections is becoming a major clinical challenge due to the rapid evolution of antibiotic resistant bacteria.As an excellent candidate to overcome antibiotic resistance,antimicrobial peptides(AMPs)that are produced from the synthetic and natural sources demonstrate a broad-spectrum antimicrobial activity with the high specificity and low toxicity.These peptides possess distinctive structures and functions by employing sophisticated mechanisms of action.This comprehensive review provides a broad overview of AMPs from the origin,structural characteristics,mechanisms of action,biological activities to clinical applications.We finally discuss the strategies to optimize and develop AMP-based treatment as the potential antimicrobial and anticancer therapeutics. 展开更多
关键词 Antimicrobial peptides Antimicrobial resistance Mechanism of action Biological activity Clinical application
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Anti-chikungunya activity of luteolin and apigenin rich fraction from Cynodon dactylon 被引量:6
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作者 Krishnan Saravana Murali Srinivasan Sivasubramanian +6 位作者 Savariar Vincent Shanmugaraj Bala Murugan Bupesh Giridaran Sundaram Dinesh Palani Gunasekaran Kaveri Krishnasamy Ramalingam Sathishkumar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第5期352-358,共7页
Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells.... Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells.Methods:The ethanolic extract of C.dactylon was subjected to silica gel column chromatography to obtain anti-chikungunya virus(CHIKV) fraction.Reverse phase-HPLC and GC-MS studies were carried out to identily the major phytochemicals in the fraction using phylochemical standards.Cytotoxicity and the potential of the fraction against CHIKV were evaluated in vitro using Vero cells.Reduction in viral replication was assessed by reverse transcriptase-polymerase chain reaction(RT-PCR) after treating the viral infected Vero cells with the fraction.Results:Reverse Phase-HPLC and GC-MS studies confirmed the presence of flavonoids,luteolin and apigenin as major phytochemicals in the anti-CHIKV ethanolic fraction of C.dactylon- The fraction was found to exhibit potent viral inhibitory activity(about 98%) at the concentration of 50 μg/mL as observed by reduction in cytopathic effect,and the cytotoxic concentration of the fraction was found to be 250 μg/mL.RT-PCR analyses indicated that the reduction in viral mRNA synthesis in fraction treated infected cells was much higher than the viral infected control cells.Conclusions:Luteolin and apigenin rich ethanolic fraction from C.dactylon can be utilized as a potential therapeutic agent against CHIKV infection as the fraction does not show cytotoxicity while inhibiting the virus. 展开更多
关键词 ANTIVIRAL activity CHIKUNGUNYA virus CYNODON dactylon Flavonoids LUTEOLIN APIGENIN
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Interactions and Biological Activity of Rare Earth Perchlorate Complexes with Alanine and Imidazole 被引量:5
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作者 HE Shui yang, CHEN Jun li, ZHANG Wei ping, LIU Xiang rong, SONG Di sheng ( Chemistry Department, North west University, Xi′an 710069, China) 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第1期66-66,共1页
The interactions of nine rare earth perchlorate complexes with alanine and imidazole were studied in methanol. The general formulae of these compounds are RE(Ala) 2Im(ClO 4) 3· n H 2O(RE=Ce, Pr, Nd, Sm, Eu,... The interactions of nine rare earth perchlorate complexes with alanine and imidazole were studied in methanol. The general formulae of these compounds are RE(Ala) 2Im(ClO 4) 3· n H 2O(RE=Ce, Pr, Nd, Sm, Eu, Gd, Tb, Yb) and La(Ala) 3Im(ClO 4) 3·H 2O, respectively. The composition and structure of the prepared compounds were determined by the chemical analysis, elemental analysis, IR spectroscopy, UV, FS spectroscopy, X ray powder diffraction, 1H NMR and solubility. The thermal decomposition processes of these complexes were studied on the basis of TG DTG. The preliminary bioassay shows that the compounds have a remarkable bacteriostasis effect on nine varieties of microbe. 展开更多
关键词 rare earths ALANINE IMIDAZOLE biology activity
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Optimization of Ultrasonic-Assisted Extraction Process of Polysaccharides from American Ginseng and Evaluation of Its Immunostimulating Activity 被引量:7
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作者 YANG Xiu-shi WANG Li-jun +2 位作者 DONG Chuan Edmund Man King Lui REN Gui-xing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第12期2807-2815,共9页
Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrason... Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrasonic power, extraction time and ratio of water to raw material to obtain a high AGP yield. The analysis of variance and response surface plots indicated that ultrasonic power was the most important factor affecting the extraction yield. The optimal conditions were ultrasonic power 400 W, extraction time 71 min, and ratio of water to raw material 33 mL g-1. Under these conditions, the yield of AGP was 8.09%, which was agreed closely to the predicted value. Gas chromatography (GC) analysis showed that AGP was composed of arabinose, rhamnose, galactose, glucose, and galacturonic acid. Fourier transform infrared spectra revealed the general characteristic absorption peaks of AGP. In addition, AGP exhibited good immunostimulating activities by up-regulating the production of nitric oxide and cytokines. Compared with hot water extraction, UAE required shorter extraction time and gave a higher extraction yield, without changing the structure and immunostimulating activity of AGP. The results indicated that UAE could be an effective and advisable technique for the large scale production of plant polysaccharides. 展开更多
关键词 ultrasonic-assisted extraction POLYSACCHARIDES American ginseng response surface methodology immunostimulating activity
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Assessment of released acrosin activity as a measurement of the sperm acrosome reaction 被引量:4
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作者 Rui-Zhi Liu Wan-Li Na +3 位作者 Hong-Guo Zhang Zhi-Yong Lin Bai-Gong Xue Zong-Ge Xu 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第2期236-242,共7页
Aim: To develop a method for assessing sperm function by measuring released acrosin activity during the acrosome reaction (AR). Methods: Human semen samples were obtained from 24 healthy donors with proven fertili... Aim: To develop a method for assessing sperm function by measuring released acrosin activity during the acrosome reaction (AR). Methods: Human semen samples were obtained from 24 healthy donors with proven fertility after 3-7 days of sexual abstinence. After collection, samples were liquefied for 30 min at room temperature. Standard semen parameters were evaluated according to World Health Organization (WHO) criteria. Calcium ionophore A23187 and progesterone (P4) were used to stimulate the sperm to undergo AR. After treatment, sperm were incubated with the supravital dye Hoechst33258, fixed in a glutaraldehyde-phosphate-buffered saline solution, and the acrosomal status was determined by fluorescence microscopy with fluorescein isothiocyanate-labeled Pisum sativum agglutinin (FITC-PSA). The percentage of sperm undergoing AR (AR%) was compared to sperm acrosin activities as assessed by spectrocolorimetry. The correlation between AR% and acrosin activity was determined by statistical analysis. Results: The AR% and released acrosin activity were both markedly increased with A23187 and P4 stimulation. Sperm motility and viability were significantly higher after stimulation with P4 versus stimulation with A23187 (P 〈 0.001). There was a significant positive correlation between released acrosin activity and AR% determined by FITC-PSA staining (r= 0.916, P 〈 0.001). Conclusion: Spectrocolorimetric measurement of released acrosin activity might serve as a reasonable alternative method to evaluate AR. (Asian J Androl 2008 Mar, 10: 236-242) 展开更多
关键词 human sperm released acrosin activity sperm function
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