A series of monochlorotriazine reactive antibacterial agents were synthesised by using 2,4,4’ - trichloro -2’ - hydroxydiphenyl ether as a starting material. The spectrum analyses (UV and MS) and elementary analy-se...A series of monochlorotriazine reactive antibacterial agents were synthesised by using 2,4,4’ - trichloro -2’ - hydroxydiphenyl ether as a starting material. The spectrum analyses (UV and MS) and elementary analy-ses were also carried out. These antibacterial agents can be used as the bacteria - resistance finishing agents of the cellulose fabrics. The treated fabrics possess excellent antibacterial activity and durable wash fastness. For ex-ample , the percentages of bacterial reduction of the fab-ric finished with reactive antibacterial agent 2RSDP are 98.5%, 98. 86% and 96.67% for Staphylococcus au-reus, Escherichia coli and Pseudomonas aeruginose re-spectively. After more than 100 times of washing at 60°C, the antibacterial activity still retains at a level of about 90% of the original. The relationships between the molecular structures of the reactive antibacterial finish-ing agents and their antibacterial activities are discussed.展开更多
BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithel...BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithelial cells has a causal role leading to infiltration of neutrophils into the colonic mucosa and subsequent development of UC.This evidence-based mechanism identifies hydrogen peroxide as a therapeutic target for reducing agents in the treatment of UC.CASE SUMMARY Presented is a 41-year-old female with a 26-year history of refractory UC.Having developed steroid dependence and never achieving complete remission on treatment by conventional and advanced therapies,she began treatment with oral R-dihydrolipoic acid(RDLA),a lipid-soluble reducing agent with intracellular site of action.Within a week,rectal bleeding ceased.She was asymptomatic for three years until a highly stressful experience,when she noticed blood in her stool.RDLA was discontinued,and she began treatment with oral sodium thiosulfate pentahydrate(STS),a reducing agent with extracellular site of action.After a week,rectal bleeding ceased,and she resumed oral RDLA and discontinued STS.To date,she remains asymptomatic with normal stool calprotectin while on RDLA.CONCLUSION STS and RDLA are reducing agents that serve as highly effective and safe therapy for the induction and maintenance of remission in UC,even in patients refractory or poorly controlled by conventional and advanced therapies.Should preliminary findings be validated by subsequent clinical trials,the use of reducing agents could potentially prevent thousands of colectomies and represent a paradigm shift in the treatment of UC.展开更多
Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importan...Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importance.This work presented poly(lactic acid)(PLA)reinforced with short-fiber and three reactive agents including anhydride and epoxide groups were selected as compatibilizers.Biocomposites were prepared by one-step meltmixing methods.The influence of reactive agents on mechanical,dynamic mechanical properties and morphology of PLA biocomposites were investigated.Tensile strength and storage modulus of PLA biocomposites incorporated with epoxide-based reactive agent was increased 13.9%and 37.4%compared to non-compatibilized PLA biocomposite,which was higher than adding anhydride-based reactive agent.SEM micrographs and Molau test exhibited an improvement of interfacial fiber-matrix adhesion in the PLA biocomposites incorporated with epoxide-based reactive agent.FTIR revealed the chemical reaction between the fiber and PLA with the presence of epoxide-based reactive agents.展开更多
Cancer cells utilize cytosolic glycolysis for their energy production even in the presence of adequate levels of oxygen (Warbug effect) due to mitochondrial defects. Dichloroacetic acid (DCA) shifts cytosolic glucose ...Cancer cells utilize cytosolic glycolysis for their energy production even in the presence of adequate levels of oxygen (Warbug effect) due to mitochondrial defects. Dichloroacetic acid (DCA) shifts cytosolic glucose metabolism to aerobic oxidation by inhibiting mitochondrial pyruvate dehydrogenase kinase (PDK) and increasing pyruvate uptake. Therefore, DCA has potential in reversing the glycolytic metabolism defect in cancerous cells. DCA is also known to induce apoptosis in a number of cancer cell lines, the mechanism of which is not well understood. In this study, an attempt has been made to investigate the effects of DCA on aggressive human breast cancer (MCF-7) cells as compared with less aggressive mouse osteoblastic (MC3T3) cells. Cell cytotoxicity was determined by MTT, crystal violet and Trypan blue exclusion assays. Western blot was used to detect any changes in the expression of apoptotic markers. Flow cytometry was used to measure apoptotic and necrotic effects of DCA. Mitochondrial integrity was determined by change in mitochondrial membrane potential (Δψm), whereas oxidative damage was determined by production of reactive oxygen species (ROS). DCA caused a concentration-dependent cytotoxicity both in MCF-7 and MC3T3 cell lines. MCF-7 cells were most affected. Flow cytometry results showed a significantly higher apoptosis in MCF-7 even at lower concentrations of DCA. However, higher concentrations of DCA were necrotic. Western blotting showed an increased expression of Mn-SOD-1 upon DCA treatment. Further, DCA decreased Δψm and increased ROS production. The effects of DCA were more pronounced on MCF-7 cells as compared to MC3T3 cells. Our results suggest that DCA-induced cytotoxicity in cancerous cells is mediated via changes in Δψm and production of ROS.展开更多
Plants have long served as a cornerstone for drug discovery,offering a vast repertoire of bioactive compounds with proven efficacy in combating oxidative stress,a pivotal driver of chronic diseases such as cancer,diab...Plants have long served as a cornerstone for drug discovery,offering a vast repertoire of bioactive compounds with proven efficacy in combating oxidative stress,a pivotal driver of chronic diseases such as cancer,diabetes,cardiovascular disorders,and neurodegenerative conditions.This review synthesizes current knowledge on plant-derived antioxidants,emphasizing their mechanisms,therapeutic potential,and quantitative efficacy validated through standardized assays.Key phytochemicals,including polyphenols,carotenoids,flavonoids,and terpenoids,neutralize reactive oxygen species(ROS)through radical scavenging,enzyme modulation,and gene regulation.For instance,lutein,a carotenoid found in leafy greens,demonstrates potent antioxidant activity with IC50 values of 1.75μg/mL against hydroxyl radicals and 2.2μg/mL in lipid peroxidation inhibition,underscoring its role in mitigating cardiovascular and ocular diseases.Similarly,quercetin,a ubiquitous flavonoid in onions and berries,exhibits remarkable ROS-scavenging capacity,with IC50 values of 0.55μg/mL,2,2-Diphenyl-1-picrylhydrazyl(DPPH)and 1.17μg/mL,2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS),supporting its use in reducing inflammation and neurodegeneration.The therapeutic promise of these compounds extends to disease-specific applications.Limonoids from citrus fruits,such as limonin(IC_(50)15-31μg/mL),enhance Phase II detoxification enzymes,offering protection against chemical carcinogens.Sulforaphane,a glucosinolate derived from cruciferous vegetables,shows potent anticancer activity with an IC50 of 85.66 mg in DPPH radical scavenging,whileβ-sitosterol(IC_(50)1.43-2.42 mM)inhibits tumor proliferation and cholesterol synthesis.Synergistic interactions further amplify their efficacy:phytoestrogens like genistein(IC_(50)13.00 ppm)and terpenoids such asα-pinene(IC_(50)12.57 mg/mL)collectively enhance antiinflammatory and antimicrobial responses,illustrating the multi-targeted nature of plant-based therapies.Beyond disease prevention,these compounds address age-related decline.Ascorbic acid(vitamin C),with an IC50 of 11.81μg/mL for antioxidant activity,mitigates skin aging and accelerates wound healing,while seleniumnanoparticles(IC_(50)0.437μg/mL)bolster immune function and reduce chemotherapy-induced toxicity.Dietary fibers,exemplified by sugar beet fibers(IC_(50)52.32μg/mL for DPPH scavenging),further contribute to cardiovascular health by lowering Low-Density Lipoprotein(LDL)cholesterol.This review not only catalogs the antioxidant prowess of phytochemicals but also highlights their translational potential.Advances in nanotechnology,such as nano-formulated curcumin,have overcome bioavailability challenges,enhancing clinical applicability.By integrating quantitative metrics(e.g.,IC50,radical scavenging rates)with mechanistic insights,this work bridges the gap between traditional knowledge and modern pharmacology.展开更多
基金Ph.D.Research Foundation of the Ministry of National Education
文摘A series of monochlorotriazine reactive antibacterial agents were synthesised by using 2,4,4’ - trichloro -2’ - hydroxydiphenyl ether as a starting material. The spectrum analyses (UV and MS) and elementary analy-ses were also carried out. These antibacterial agents can be used as the bacteria - resistance finishing agents of the cellulose fabrics. The treated fabrics possess excellent antibacterial activity and durable wash fastness. For ex-ample , the percentages of bacterial reduction of the fab-ric finished with reactive antibacterial agent 2RSDP are 98.5%, 98. 86% and 96.67% for Staphylococcus au-reus, Escherichia coli and Pseudomonas aeruginose re-spectively. After more than 100 times of washing at 60°C, the antibacterial activity still retains at a level of about 90% of the original. The relationships between the molecular structures of the reactive antibacterial finish-ing agents and their antibacterial activities are discussed.
文摘BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithelial cells has a causal role leading to infiltration of neutrophils into the colonic mucosa and subsequent development of UC.This evidence-based mechanism identifies hydrogen peroxide as a therapeutic target for reducing agents in the treatment of UC.CASE SUMMARY Presented is a 41-year-old female with a 26-year history of refractory UC.Having developed steroid dependence and never achieving complete remission on treatment by conventional and advanced therapies,she began treatment with oral R-dihydrolipoic acid(RDLA),a lipid-soluble reducing agent with intracellular site of action.Within a week,rectal bleeding ceased.She was asymptomatic for three years until a highly stressful experience,when she noticed blood in her stool.RDLA was discontinued,and she began treatment with oral sodium thiosulfate pentahydrate(STS),a reducing agent with extracellular site of action.After a week,rectal bleeding ceased,and she resumed oral RDLA and discontinued STS.To date,she remains asymptomatic with normal stool calprotectin while on RDLA.CONCLUSION STS and RDLA are reducing agents that serve as highly effective and safe therapy for the induction and maintenance of remission in UC,even in patients refractory or poorly controlled by conventional and advanced therapies.Should preliminary findings be validated by subsequent clinical trials,the use of reducing agents could potentially prevent thousands of colectomies and represent a paradigm shift in the treatment of UC.
文摘Poor interfacial adhesion between biobased thermoplastics and natural fibers is recognized as a major drawback for biocomposites.To be applicable for the large-scale production,a simple method to handle is of importance.This work presented poly(lactic acid)(PLA)reinforced with short-fiber and three reactive agents including anhydride and epoxide groups were selected as compatibilizers.Biocomposites were prepared by one-step meltmixing methods.The influence of reactive agents on mechanical,dynamic mechanical properties and morphology of PLA biocomposites were investigated.Tensile strength and storage modulus of PLA biocomposites incorporated with epoxide-based reactive agent was increased 13.9%and 37.4%compared to non-compatibilized PLA biocomposite,which was higher than adding anhydride-based reactive agent.SEM micrographs and Molau test exhibited an improvement of interfacial fiber-matrix adhesion in the PLA biocomposites incorporated with epoxide-based reactive agent.FTIR revealed the chemical reaction between the fiber and PLA with the presence of epoxide-based reactive agents.
文摘Cancer cells utilize cytosolic glycolysis for their energy production even in the presence of adequate levels of oxygen (Warbug effect) due to mitochondrial defects. Dichloroacetic acid (DCA) shifts cytosolic glucose metabolism to aerobic oxidation by inhibiting mitochondrial pyruvate dehydrogenase kinase (PDK) and increasing pyruvate uptake. Therefore, DCA has potential in reversing the glycolytic metabolism defect in cancerous cells. DCA is also known to induce apoptosis in a number of cancer cell lines, the mechanism of which is not well understood. In this study, an attempt has been made to investigate the effects of DCA on aggressive human breast cancer (MCF-7) cells as compared with less aggressive mouse osteoblastic (MC3T3) cells. Cell cytotoxicity was determined by MTT, crystal violet and Trypan blue exclusion assays. Western blot was used to detect any changes in the expression of apoptotic markers. Flow cytometry was used to measure apoptotic and necrotic effects of DCA. Mitochondrial integrity was determined by change in mitochondrial membrane potential (Δψm), whereas oxidative damage was determined by production of reactive oxygen species (ROS). DCA caused a concentration-dependent cytotoxicity both in MCF-7 and MC3T3 cell lines. MCF-7 cells were most affected. Flow cytometry results showed a significantly higher apoptosis in MCF-7 even at lower concentrations of DCA. However, higher concentrations of DCA were necrotic. Western blotting showed an increased expression of Mn-SOD-1 upon DCA treatment. Further, DCA decreased Δψm and increased ROS production. The effects of DCA were more pronounced on MCF-7 cells as compared to MC3T3 cells. Our results suggest that DCA-induced cytotoxicity in cancerous cells is mediated via changes in Δψm and production of ROS.
基金funded by the project of Scientific Research Start-up Funds for Doctoral Talents of Zhaotong University-Mingzheng Duan,Grant number:202406Young Talent Project of Talent Support Program for the Development of Yunnan,Grant number:210604199008271015.
文摘Plants have long served as a cornerstone for drug discovery,offering a vast repertoire of bioactive compounds with proven efficacy in combating oxidative stress,a pivotal driver of chronic diseases such as cancer,diabetes,cardiovascular disorders,and neurodegenerative conditions.This review synthesizes current knowledge on plant-derived antioxidants,emphasizing their mechanisms,therapeutic potential,and quantitative efficacy validated through standardized assays.Key phytochemicals,including polyphenols,carotenoids,flavonoids,and terpenoids,neutralize reactive oxygen species(ROS)through radical scavenging,enzyme modulation,and gene regulation.For instance,lutein,a carotenoid found in leafy greens,demonstrates potent antioxidant activity with IC50 values of 1.75μg/mL against hydroxyl radicals and 2.2μg/mL in lipid peroxidation inhibition,underscoring its role in mitigating cardiovascular and ocular diseases.Similarly,quercetin,a ubiquitous flavonoid in onions and berries,exhibits remarkable ROS-scavenging capacity,with IC50 values of 0.55μg/mL,2,2-Diphenyl-1-picrylhydrazyl(DPPH)and 1.17μg/mL,2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS),supporting its use in reducing inflammation and neurodegeneration.The therapeutic promise of these compounds extends to disease-specific applications.Limonoids from citrus fruits,such as limonin(IC_(50)15-31μg/mL),enhance Phase II detoxification enzymes,offering protection against chemical carcinogens.Sulforaphane,a glucosinolate derived from cruciferous vegetables,shows potent anticancer activity with an IC50 of 85.66 mg in DPPH radical scavenging,whileβ-sitosterol(IC_(50)1.43-2.42 mM)inhibits tumor proliferation and cholesterol synthesis.Synergistic interactions further amplify their efficacy:phytoestrogens like genistein(IC_(50)13.00 ppm)and terpenoids such asα-pinene(IC_(50)12.57 mg/mL)collectively enhance antiinflammatory and antimicrobial responses,illustrating the multi-targeted nature of plant-based therapies.Beyond disease prevention,these compounds address age-related decline.Ascorbic acid(vitamin C),with an IC50 of 11.81μg/mL for antioxidant activity,mitigates skin aging and accelerates wound healing,while seleniumnanoparticles(IC_(50)0.437μg/mL)bolster immune function and reduce chemotherapy-induced toxicity.Dietary fibers,exemplified by sugar beet fibers(IC_(50)52.32μg/mL for DPPH scavenging),further contribute to cardiovascular health by lowering Low-Density Lipoprotein(LDL)cholesterol.This review not only catalogs the antioxidant prowess of phytochemicals but also highlights their translational potential.Advances in nanotechnology,such as nano-formulated curcumin,have overcome bioavailability challenges,enhancing clinical applicability.By integrating quantitative metrics(e.g.,IC50,radical scavenging rates)with mechanistic insights,this work bridges the gap between traditional knowledge and modern pharmacology.