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Effects of Bisphenol A and Its Substitute, Bisphenol F, on the Gut Microbiota in Mice
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作者 MENG Li Ying TAO Wen Fu +5 位作者 LI Jing ZHU Min ZHONG De Bin ZHOU Jing QIN Xue WEI Rong Guo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第1期19-30,共12页
Objective The aim of this study was to assess the impact of bisphenol A(BPA)and its substitute,bisphenol F(BPF),on the colonic fecal community structure and function of mice.Methods We exposed 6–8-week-old male C57BL... Objective The aim of this study was to assess the impact of bisphenol A(BPA)and its substitute,bisphenol F(BPF),on the colonic fecal community structure and function of mice.Methods We exposed 6–8-week-old male C57BL/6 mice to 5 mg/(kg∙day)and 50μg/(kg∙day)of BPA or BPF for 14 days.Fecal samples from the colon were analyzed using 16S rRNA sequencing.Results Gut microbiome community richness and diversity,species composition,and function were significantly altered in mice exposed to BPA or BPF.This change was characterized by elevated levels of Ruminococcaceae UCG-010 and Oscillibacter and decreased levels of Prevotella 9 and Streptococcus.Additionally,pathways related to carbohydrate and amino acid metabolism showed substantial enrichment.Conclusion Mice exposed to different BP analogs exhibited distinct gut bacterial community richness,composition,and related metabolic pathways.Considering the essential role of gut bacteria in maintaining intestinal homeostasis,our study highlights the intestinal toxicity of BPs in vertebrates. 展开更多
关键词 bisphenol A(BPA) bisphenol F(BPF) 16S rRNA MICROBIOTA
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Garcinia Kola and Kolaviron Attenuates Bisphenol A-Induced Memory Impairment and Hippocampal Neuroinflammation in Male Wistar Rats
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作者 Nazizi Adamu Kayinu Bernard Omokheshi Adele Abayomi Oluwatosin Ige 《Journal of Biosciences and Medicines》 2024年第2期111-130,共20页
Bisphenol A (BPA), a toxicant which can leach into food from plastic containers, is reported to induce neurotoxicity among others via oxidative mechanisms. However, antioxidant compounds have been suggested to mitigat... Bisphenol A (BPA), a toxicant which can leach into food from plastic containers, is reported to induce neurotoxicity among others via oxidative mechanisms. However, antioxidant compounds have been suggested to mitigate BPA-induced toxicities. Garcinia kola (GK) and its bioactive compound, kolaviron, are well-established natural antioxidants, which can exert protective effects against BPA-induced toxicities. This study was designed to investigate the likely mitigating effect of GK and kolaviron on BPA-induced memory impairment and hippocampal neuroinflammation in male Wistar rats. Thirty-five rats were equally grouped and treated as follows: I and II received distilled water and corn oil, respectively at 0.2 mL, while III - VII received BPA (50 mg/kg), BPA + GK (200 mg/kg), BPA + kolaviron (200 mg/kg), GK and kolaviron, respectively for 28 days p.o. Thereafter, behavioral studies were done using the Novel Object Recognition and Y maze tests. Subsequently under anaesthesia, the hippocampus in each animal was dissected out, homogenized and analysed for malondialdehyde, superoxide dismutase, catalase, reduced glutathione, glutathione transferase, nitrites, interleukin-6, tumour necrosis factor-α, acetylcholinesterase, glutamate acid decarboxylase, and arginase activity. Data were analyzed by ANOVA and Tukey Post-hoc test at p p Garcinia kola and Kolaviron mitigate bisphenol A-induced memory impairment and neuroinflammation via antioxidant potentiation and neurotransmitter balance. 展开更多
关键词 bisphenol A Memory Impairment NEUROINFLAMMATION NEUROPROTECTION Garcinia Kola KOLAVIRON ANTIOXIDANT
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New environmental factors related to diabetes risk in humans:Emerging bisphenols used in synthesis of plastics
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作者 Rafael Moreno-Gómez-Toledano María Delgado-Marín +13 位作者 Alberto Cook-Calvete Claudia González-Cucharero Nunzio Alcharani Beatriz Jiménez-Guirado Ignacio Hernandez Rafael Ramirez-Carracedo Laura Tesoro Laura Botana Sandra Sánchez-Esteban Javier Diez-Mata Jose Luis Zamorano Ricardo J.Bosch Carlos Zaragoza Marta Saura 《World Journal of Diabetes》 SCIE 2023年第8期1301-1313,共13页
BACKGROUND Diabetes mellitus(DM)is one of the largest global health emergencies of the 21st century.In recent years,its connection with environmental pollutants,such as bisphenol A(BPA),has been demonstrated;consequen... BACKGROUND Diabetes mellitus(DM)is one of the largest global health emergencies of the 21st century.In recent years,its connection with environmental pollutants,such as bisphenol A(BPA),has been demonstrated;consequently,new structurally similar molecules are used to replace BPA in the plastics industry(BPS,BPF and BPAF).AIM To carry out a systematic review to allow coherent evaluation of the state of the art.Subsequently,a meta-analysis was performed to unify the existing quantitative data.METHODS Firstly,a systematic review was carried out,using the terms“(bisphenol)AND(Diabetes OR Hyperglycemia)”,to maximize the number of results.Subsequently,three authors analyzed the set of articles.Finally,a meta-analysis was performed for each BP,using RevMan software.In addition,funnel plots were developed to study publication bias.RESULTS The systematic analysis of the literature revealed 13 recent articles(2017–2023)related to the study paradigm.The qualitative analysis showed interesting data linking diabetes to the three most widely used substitute BPs in the industry:BPS,BPF and BPAF.Finally,the meta-analysis determined a positive relationship with BPS,BPF and BPAF,which was only statistically significant with BPS.CONCLUSION There is a need to apply the precautionary principle,regulating the use of new BPs.Therefore,replacing BPA with BPS,BPF or BPAF is unlikely to protect the population from potential health risks,such as DM. 展开更多
关键词 bisphenol S bisphenol F bisphenol AF Diabetes mellitus Systematic review META-ANALYSIS
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Bisphenol A in Fluid and Powdered Milk Samples and Associated Child Dietary Exposures
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作者 Patrícia dos Santos Souza Thomas Manfred Krauss +1 位作者 André Victor Sartori Shirley de Mello Pereira Abrantes 《Journal of Environmental Protection》 2023年第8期603-615,共33页
Bisphenol A (BPA) is a synthetic chemical found in a wide range of consumer products and consumables that humans are exposed to. The aim of this study was to determine BPA contamination levels in 51 milk samples sold ... Bisphenol A (BPA) is a synthetic chemical found in a wide range of consumer products and consumables that humans are exposed to. The aim of this study was to determine BPA contamination levels in 51 milk samples sold in the Rio de Janeiro Metropolitan Region, Brazil. Bisphenol A was detected (≥limit of detection, LOD) in five of the analyzed samples (9.8%) and quantified (≥limit of quantification, LOQ) in two (3.8%). The estimated daily intake (EDI) for children aged up to 12 months ranged from 24.95 to 97.72 ng/kg body weight/day, lower than the established European Union tolerable daily intake value. Recent evidence, however, suggests that even low doses of endocrine disruptors such as BPA may pose potential health risks, even more so when exposure occurs at such an early life stage. 展开更多
关键词 bisphenol A UHPLC-MS/MS QUECHERS Cow’s Milk Dietary Exposure Assessment
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Bisphenol A (BPA) Contamination in Whole Milk Marketed in Different Packages
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作者 Patrícia dos Santos Souza Thomas Manfred Krauss +1 位作者 André Victor Sartori Shirley de Mello Pereira Abrantes 《Journal of Environmental Protection》 2023年第9期711-724,共14页
Bisphenol A (BPA), an important endocrine disruptor, is used in the manufacturing of various materials, including food packaging. Ingestion of contaminated foodstuffs is, in fact, the most relevant form of exposure to... Bisphenol A (BPA), an important endocrine disruptor, is used in the manufacturing of various materials, including food packaging. Ingestion of contaminated foodstuffs is, in fact, the most relevant form of exposure to this substance. However, scarce data on the presence of this contaminant in milk, or whether different types of food packaging influence food contamination are available in Brazil. This study, therefore, aimed to evaluate the BPA contamination of whole milk (fluid and powder) samples packaged in different types of packaging (Tetra Pak?;PET: Poly (ethylene terephthalate;Metallic can (epoxy resin);Polyethylene (PE) and poly (vinylidene chloride) (PVDC);Laminated Film - Metallized Polyester-Polyethylene and glass) and marketed metropolitan region of Rio de Janeiro, Brazil. An analytical method for the BPA determination in milk was optimized for both fluid (pasteurized and ultra-high temperature) and powdered milk samples. A modified QuEChERS method was applied, and BPA determinations were conducted by ultra-performance liquid chromatography coupled with sequential mass spectrometry (HPLC-MS/MS). The validated method was then applied to 51 milk samples, where BPA was detected in five samples (9.8%) and quantified in two (3.8%). 展开更多
关键词 bisphenol A. Packaging MIGRATION MILK Endocrine Disruptors
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Association between urinary concentrations of bisphenol A substitutes and diabetes in adults
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作者 Rafael Moreno-Gómez-Toledano Esperanza Vélez-Vélez +2 位作者 María I Arenas Marta Saura Ricardo J Bosch 《World Journal of Diabetes》 SCIE 2022年第7期521-531,共11页
BACKGROUND Due to new restrictions on the use of bisphenol A(BPA),industries are beginning to replace it with derived molecules such as bisphenol S and F(BPS and BPF).There is extensive evidence in the academic litera... BACKGROUND Due to new restrictions on the use of bisphenol A(BPA),industries are beginning to replace it with derived molecules such as bisphenol S and F(BPS and BPF).There is extensive evidence in the academic literature on the potential health effects of BPA,which is known to be a diabetogenic molecule.However,there are few publications related to new compounds derived from BPA.AIM To perform an epidemiological study of urinary BPS and BPF in the American National Health and Nutrition Examination Survey(NHANES)cohort,and analyze their possible relationship with diabetes mellitus.METHODS NHANES datasets from 2013 to 2016 were used due to the urinary BPF and BPS availability.Data from 3658 adults were analyzed to perform regression analysis exploring the possible relationship between BPA-derived compounds and diabetes.RESULTS Descriptive statistics,linear regression modeling,and logistic regression analysis revealed a significant relationship between urinary BPS,but not BPF,and diabetes risk.Additionally,a relationship was observed between both compounds and hypertension and a slight relationship between BPF and dyslipidemia.CONCLUSION In the present study,a strong relationship between urinary BPS,not BPF,and diabetes risk has been determined.BPA substitute molecules do not exempt the population from potential health risks. 展开更多
关键词 bisphenol S bisphenol F Diabetes mellitus National Health and Nutrition Examination Survey URINE
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Enhanced visible-light-assisted peroxymonosulfate activation over MnFe_(2)O_(4) modified g-C_(3)N_(4)/diatomite composite for bisphenol A degradation 被引量:2
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作者 Xiangwei Zhang Chunquan Li +5 位作者 Ting Chen Ye Tan Xiaorui Liu Fang Yuan Shuilin Zheng Zhiming Sun 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第6期1169-1179,共11页
The MnFe_(2) O_(4)/g-C_(3) N_(4)/diatomite composites(Mn/G/D) were prepared via a facile precipitation-calcination method in this study.The Mn/G/D possessed higher specific surface area,lower electron-hole pairs' ... The MnFe_(2) O_(4)/g-C_(3) N_(4)/diatomite composites(Mn/G/D) were prepared via a facile precipitation-calcination method in this study.The Mn/G/D possessed higher specific surface area,lower electron-hole pairs' recombination rate,as well as wider and stronger visible light absorption capacity.Since the synergistic effect between g-C_(3 )N_(4) and MnFe_(2) O_(4),the photogene rated electron could transfer from g-C3 N4 to MnFe_(2) O_(4),which could promote the migration of electrons as well as enhance the photocatalytic activity and peroxymonosulfate(PMS) activation efficiency.Mn/G/D-5% composite displayed the excellent degradation performance of bisphenol A(BPA) with the removal efficiency of 99.9% under PMS/Vis system,which was approximately 2.47 and 63.8 times as high as that of the Mn/G/D-5%/PMS and Mn/G/D-5%/Vis system,respectively.Moreover,negative electricity derived from diatomite surface also promoted the photogenerated carriers' migration,and the degradation rate constant was around 2.4 times higher than that of MnFe_(2) O_(4)/g-C_(3) N_(4)(Mn/G).In addition,quenching experiments showed that both radical pathway(h^(+),·OH,·O_(2)^(-)and SO_(4)·^(-)) and non-radical pathway(^(1) O_(2)) were responsible for the degradation of BPA. 展开更多
关键词 bisphenol A PHOTOCATALYSIS PEROXYMONOSULFATE MnFe_(2)O_(4) g-C_(3)N_(4) DIATOMITE
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Polymerization of Bisphenol A Epoxy Resin with Polyethylene glycol 被引量:2
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作者 Zhen Zhong YANG De Lu ZHAo Mao XU(Polymer Physics Laboratory, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100080) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期725-728,共4页
The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied.It is shown that ... The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied.It is shown that there exist two competitive reactions:I, self polymerization of epoxy resin via chain growth and II, copolymerization of epoxy resin with PEG via step growth. At high concentration of the catalyst, reaction I dominates and reaction II is negligible. On the contrary, at low concentration of the catalyst, reaction II dominates and block copolymers are formed. In the intermediate case, the two reactions are comparable with the result that a gel structure is obtained. 展开更多
关键词 PEG Polymerization of bisphenol A Epoxy Resin with Polyethylene glycol
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Preparation of polypyrrole/nanosilica composite for solid-phase microextraction of bisphenol and phthalates migrated from containers to eye drops and injection solutions 被引量:2
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作者 Mehdi Ansari Dogaheh Mansoureh Behzadi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第3期185-192,共8页
This paper describes the electrodeposition of polyphosphate-doped polypyrrole/nanosilica nano-composite coating on steel wire for direct solid-phase microextraction of bisphenol A and five phthalates. We optimized inf... This paper describes the electrodeposition of polyphosphate-doped polypyrrole/nanosilica nano-composite coating on steel wire for direct solid-phase microextraction of bisphenol A and five phthalates. We optimized influencing parameters on the extraction efficiency and morphology of the nanocomposite such as deposition potential, concentration of pyrrole and polyphosphate, deposition time and the nanosilica amount. Under the optimized conditions, characterization of the nanocomposite was inves-tigated by scanning electron microscopy and Fourier transform infra-red spectroscopy. Also, the factors related to the solid-phase microextraction method including desorption temperature and time, extrac-tion temperature and time, ionic strength and pH were studied in detail. Subsequently, the proposed method was validated by gas chromatography-mass spectrometry by thermal desorption and acceptable figures of merit were obtained. The linearity of the calibration curves was between 0.01 and 50 ng/mL with acceptable correlation coefficients (0.9956-0.9987) and limits of detection were in the range 0.002-0.01 ng/mL. Relative standard deviations in terms of intra-day and inter-day by five replicate analyses from aqueous solutions containing 0.1 ng/mL of target analytes were in the range 3.3%-5.4% and 5%-7.1%, respectively. Fiber-to-fiber reproducibilities were measured for three different fibers prepared in the same conditions and the results were between 7.3% and 9.8%. Also, extraction recoveries at two different concentrations were ≥96%. Finally, the suitability of the proposed method was demonstrated through its application to the analysis of some eye drops and injection solutions. 展开更多
关键词 SOLID-PHASE MICROEXTRACTION Gas chromatography-mass spectrometry Polyphosphate-doped POLYPYRROLE NANOSILICA PHTHALATES bisphenolA
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Exposure to environmental bisphenol A inhibits HTR-8/SVneo cell migration and invasion 被引量:1
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作者 Pu Wei Dongqing Ru +5 位作者 Xiaoqian Li Dongyan Shi Mingshun Zhang Qing Xu Hong Zhou Shuang Wen 《The Journal of Biomedical Research》 CAS CSCD 2020年第5期369-378,I0007,共11页
Environmental pollutants,such as bisphenol A(BPA) have recently been implicated in the development of adverse birth outcomes.However,the underlying teratogenic mechanisms remain unclear.We investigated the effects of ... Environmental pollutants,such as bisphenol A(BPA) have recently been implicated in the development of adverse birth outcomes.However,the underlying teratogenic mechanisms remain unclear.We investigated the effects of BPA on the migration and invasion of human primary extravillous trophoblast HTR-8/SVneo cells.Our results indicated that BPA reduced cell migration and invasion.Moreover,it altered the ratio of matrix metalloproteinases(MMPs) and tissue inhibitors of MMPs(TIMPs) by downregulating MMP-2 and MMP-9,and upregulating TIMP-1 and TIMP-2.Furthermore,BPA suppressed integrin β1,integrin α5,and vimentin.Interestingly,BPA-induced invasion was partially restored by G15,a membrane G-protein-coupled estrogen receptor 30 antagonist.We further revealed that 42 proteins were differentially expressed by mass spectrometry analysis,which could be divided into three categories based on gene ontology including biological process,cellular component,and molecular function.These results suggest that BPA reduces HTR-8/SVneo cell migration and invasion by downregulating MMP-2 and MMP-9,up-regulating TIMP-1 and TIMP-2,and suppressing adhesion molecules. 展开更多
关键词 bisphenol A HTR8/SVneo cells cell invasion INTEGRINΒ1
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Highly selective synthesis for 4,4′-bisphenol F from phenol and formaldehyde catalyzed with [C_4mim][HSO_4] ionic liquid 被引量:2
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作者 Danfeng Wang Zhicheng He +3 位作者 Zhimin Wu Ying Tan Yongfei Li Yuejin Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1166-1170,共5页
The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-... The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-bisphenol F were investigated. The hydrogen bonding between the hydroxyl of phenol and the C2-position hydrogen of imidazole moiety in hydrophilic imidazole-based ionic liquid has important influence on the selectivity for 4,4′-bisphenol F, and under the conditions of the molar ratio of phenol/[C4mim][HSO4] 1:1, reaction temperature65 °C and the theoretical molar ratio of phenol/formaldehyde 2:1, the selectivity for 4,4′-bisphenol F reached69.1%. Compared with the high phenol/formaldehyde ratio reported in literatures, the low molar ratio of phenol/formaldehyde and the low reaction temperature can greatly reduce energy consumption, and has important significance for industrial application. 展开更多
关键词 4 4′-bisphenol F PHENOL FORMALDEHYDE 1-Butyl-3-methylimidazolium hydrogen sulfate
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Adsorption of Propazine, Simazine and Bisphenol A on the Surface of Nanoparticles of Iron Oxide Nanoparticles of Carbon and Metallic Oxides 被引量:1
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作者 Matthewos Eshete Jerrano Bowleg +3 位作者 Selene G. Perales Maxwell Okunrobo Dominique Watkins Hattie Spencer 《Journal of Environmental Protection》 2018年第1期13-24,共12页
Simazine and propazine are selective triazine herbicides currently in use to control broad-leaved weeds and annual grasses around the world. Bisphenol A (BPA) is an industrial chemical used in the production of polyca... Simazine and propazine are selective triazine herbicides currently in use to control broad-leaved weeds and annual grasses around the world. Bisphenol A (BPA) is an industrial chemical used in the production of polycarbonate plastics often found in consumer goods, such as plastic containers, baby bottles etc. These synthetic compounds are known to increase the risk of cancer, cause adverse reproductive effect in reptiles, mammals, birds, humans, and lead to other health problems. They have become some of the principal agents of contamination in water bodies around the world through herbicide runoff, industrial waste and leaching. Some triazines such as atrazine are banned in most European countries for over ten years due to their adverse reproductive effect in mammals, birds and humans;however propazine and simazine are still in use around the world. The removal of these compounds from contaminated water is an exigent challenge. In this study, we investigated their affinity for the surface of nanoparticles (NPS) and standard metallic oxides in an effort to exploit the unique potential applications of NPS for water purification systems. We studied the adsorption of the two triazines and BPA on the surface of NPS of iron (III) oxide, NPS of carbon, bulk iron (III) oxide and aluminum oxide at pH 6 and pH 8 using UV-Visible spectroscopy. Result indicates that these compounds have different affinity towards the surface of metallic oxides and carbon at various pHs. In general, there is relatively high adsorption of some of these compounds on the surface of NPS compared to bulk particles. NPS of carbon have shown the highest affinity for all the three compounds. The lower pH was found to be favorable for all of the compounds except for BPA. BPA have shown high adsorption at pH 8 than at pH 6. 展开更多
关键词 TRIAZINE ADSORPTION of NANOPARTICLES NANOPARTICLES of Iron Oxide NANOPARTICLES of CARBON bisphenol A
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Effect of Perinatal Bisphenol A Exposure on Serum Lipids and Lipid Enzymes in Offspring Rats of Different Sex 被引量:1
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作者 GAO Liang WANG Han Ning +4 位作者 ZHANG Ling PENG Fang Yuan JIA Yue WEI Wei JIA Li Hong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第9期686-689,共4页
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关键词 Effect of Perinatal bisphenol A Exposure on Serum Lipids and Lipid Enzymes in Offspring Rats of Different Sex BPA ADP
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Transient and Steady State Currents of Bisphenol A Corncobs Sample 被引量:1
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作者 Taha A. Hanafy 《Advances in Materials Physics and Chemistry》 2011年第3期99-107,共9页
Transient current (I-t), current-voltage (I-V) characteristics, and dc conductivity ln(σ) for bisphenol A corn-cobs (BPACC) sample were investigated. At higher temperatures, I-V characteristics reveal that the dc cur... Transient current (I-t), current-voltage (I-V) characteristics, and dc conductivity ln(σ) for bisphenol A corn-cobs (BPACC) sample were investigated. At higher temperatures, I-V characteristics reveal that the dc cur-rent for the sample undergoes two regions one due to ohmic conduction and the other has been attributed to Space charge limited current (SCLC). The activation energy (Ea), the electron mobility μo), effective electron mobility ?μe), the concentration of the charge’s concentrations in conduction band, trapping factor (θ) and the trap concentration (Nt) were calculated. At lower temperatures, the dc current exhibits a peculiar behavior for I-t regime and I-V characteristics. Transient current of BPACC sample exhibits approximately constant value at constant electric field and it has saturation value for I-V characteristics. The attained results suggest strongly the applicability of this material in the electrical applications. 展开更多
关键词 bisphenol A Corncobs TRANSIENT CURRENT I-V Characteristics Conduction MECHANISM
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RHEOLOGICAL PROPERTIES OF LIQUID CRYSTALLINE COPOLY (ρ-HYDR0XYBENZ0ATE/BISPHENOL A TEREPHTHALATE)
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作者 王勇 吴大诚 李瑞霞 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1996年第2期97-104,共8页
Various aspects of the rheological behaviour of liquid crystalline copolyesters, i.e.,samples of copoly (p-hydroxybenzoate / bisphenol A terephthalate), were explored by usingInstron capillary rheometer. The experim... Various aspects of the rheological behaviour of liquid crystalline copolyesters, i.e.,samples of copoly (p-hydroxybenzoate / bisphenol A terephthalate), were explored by usingInstron capillary rheometer. The experimental results indicated that the apparent viscositywas affected significantly by shear rate, melt temperature and p-hydroxybenzoate unit con-tent. The flow activation energies △E<sub>η</sub> are in the range of 205.1 to 74.5 kJ/mol, dependingon the shear rate of 10-1000 s<sup>-1</sup>, at temperature 568-603K. These copolyesters exhibit ayield phenomenon in the shear flow, and the values of yield stress decrease with increasingtemperature. It is quite unusual that the extrudate of the copolyester shows the smallerswelling ratio even than unity at the lower temperature and lower shear rates. 展开更多
关键词 RHEOLOGY Copoly (p-hydroxybenzoate/bisphenol A terephthalate) Liquid CRYSTALLINE polymer Yield stress
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Cistanchetubulosa(Schenk)R.Wight amelioratesbisphenol A-induced testicular and sperm toxicity in rats through steroidogenesis and redox pathways
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作者 Zhi-hui JIANG Wen-yan XIE +2 位作者 Meng WANG Jian WANG Xiao-ying ZHANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2015年第S1期100-100,共1页
OBJECTIVE Bisphenol A(BPA)is a commonly used phenolic environmental estrogen that impacts male reproductive system.Cistanchetubulosa(CT)is a traditional Chinese medicine used to boost male sexual activity.It has been ... OBJECTIVE Bisphenol A(BPA)is a commonly used phenolic environmental estrogen that impacts male reproductive system.Cistanchetubulosa(CT)is a traditional Chinese medicine used to boost male sexual activity.It has been proved for increasing the expression of steroidogenic enzyme and remarkable antioxidant activity.This study aimed to investigate the mechanisms behind the possible protective effects of CT against BPA-induced testicular and sperm toxicity in rats.METHODS CT was identified by 5.8sgene sequencing.The major compositions(echinacosideand acteoside)of CT were quantified by HPLC method.CT(200or 400mg·kg-1)or VE(positive control,300mg·kg-1)and BPA(200mg·kg-1)were administered orally(one time per day)to adult male ratsfor 6weeks.The sperm parameters were observed by dark-field microscope;serum hormone levels(FSH,LH and T)were tested by radio immunosorbent;LDH-x activity,redox balance status(content of MDA,GSH,H2O2 and OH-,and activity of SOD)were evaluated using commercial kits;the expression of the key steroidogenic enzymes were evaluated by qRT-PCR,heat map,immunofluorescence and Western blotting.RESULTS The CT treatment reversed BPA-induced abnormal in sperm characteristics,testicular structure and LDH-x activity,as well as normalized serum testosterone.CT increased both mRNA and protein expressions of key steroidogenic enzymes including StAR,CYP11A1,3β-HSD,17β-HSD and CYP17A1,suggesting that CT enhanced sex hormone synthesis.Moreover,the remarkable antioxidant effect of CT contributed to its protection against BPA-induced testicular toxicity,which was evidenced by the normalization of testicular,redox markers(MDA,H2O2,OH-and GSH contents,and SOD activity)after CT treatment.CONCLUSION CT effectively attenuated BPA-induced poor sperm quality and testicular toxicity in rats through steroidogenesis and redox pathways. 展开更多
关键词 Cistanchetubulosa(Schenk)R.Wight bisphenol A SPERM
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TOXICITY OF BISPHENOL A ON THE GROWTH OF ZEBRAFISH EMBRYOS
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作者 DUAN Zheng-Hua and ZHU Lin (College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China) 《水生生物学报》 CAS CSCD 北大核心 2006年第6期638-642,共5页
In order to evaluate the toxicity of the bisphenol A (BPA) on the growth of zebrafish embryos, fertilized eggs were exposed to the concentration of 2.00, 4.00, 6.00, 8.00, 10.00, 15.00, 18.00, 22.00 and 25.00mg/L BPA ... In order to evaluate the toxicity of the bisphenol A (BPA) on the growth of zebrafish embryos, fertilized eggs were exposed to the concentration of 2.00, 4.00, 6.00, 8.00, 10.00, 15.00, 18.00, 22.00 and 25.00mg/L BPA for 72 h at 26±1℃. The results revealed that the sublethal toxicological endpoints induced by BPA were:delayed hatch> blood balk >cyst>altered axial curvature and tail malformation. The median embryo lethal concentration (LC50) after 24 h was 16.36 mg/L. We concluded that the BPA toxicity on zebrafish embryos were caused before 8h exposure and it was not the result of long-term accumulation. Therefore, BPA maybe cause altered gene expression at the early stage of zebrafish embryos. In the further studies, we will use the technology of genetic chips to look for the toxic mechanism of BPA. 展开更多
关键词 bisphenol A Zebrafish embryos TOXICITY
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PREPARATION OF LIQUID CRYSTALLINE COPOLYESTERS WITH SPACERS BASED ON BISPHENOL-A,BISPHENOL-S OR POLYSULFONE BY DIRECT POLYCONDENSATION
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作者 汪平平 张鸿志 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第1期9-15,共7页
Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild con... Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild conditions. The electron-rich hydroxyl groups of bisphenols favoured the polycondensation reaction and the order of relative reactivities of bisphenols is as follow:bisphenoI-A】 hydroquinone ~bisphenol-S】 chlorohydroquinone. The mesomorphic properties of copolyesters were examined by birefringence under polarizing microscope, melt transparency. DSC and X-ray diffraction. The minimum molar fraction of mesogenic units needed for the appearance of liquid crystallinity is not higher than 0. 1 despite of the different varieties and lengths of the spacers studied. 展开更多
关键词 dicarboxylic CRYSTALLINITY bisphenol aromatic hydroxyl transparency MOLAR appearance OLIGOMER pyridine
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Gracilaria changii(Rhodophyta) alleviates bisphenol A-induced adverse reproductive abnormalities in mice
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作者 Chong Lee Ng Gim Cheong Tan +2 位作者 Yoon-Yen Yow Mukesh Kumar Gupta Phek Jin Kwong 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2021年第1期34-60,共27页
Objective:To evaluate the potential of Gracilaria changii extract in ameliorating the potential adverse effects of bisphenol A.Methods:The antioxidant capacity of Gracilaria changii extracted using different solvents(... Objective:To evaluate the potential of Gracilaria changii extract in ameliorating the potential adverse effects of bisphenol A.Methods:The antioxidant capacity of Gracilaria changii extracted using different solvents(methanol,ethanol,and aqueous)was studied.The mice were administered by oral gavage with bisphenol A(60 mg/kg body weight)for 6 weeks with or without Gracilaria changii aqueous extract.Thereafter,the mice were either euthanized for histology and immunohistochemistry studies or mated to evaluate the pregnancy rate.Results:Gracilaria changii aqueous extract showed the highest antioxidant properties compared with extract using methanol and ethanol.The aqueous extract of Gracilaria changii improved the uterus index and uterine lipid peroxidation after bisphenol A exposure,although the uterine expressions of estrogen receptors and complement C3 were not improved.Histological evaluation of the uterus during the estrus stage has revealed that the extract could mitigate bisphenol A-induced adverse effects in the uterus as there was a lower percentage of mice showing abnormalities like decreased eosin staining in the myometrium,and decrease in the number of eosinophil and endometrial glands in the endometrium.Besides,Gracilaria changii aqueous extract improved the pregnancy rate of mice administered with bisphenol A.Conclusions:Gracilaria changii extract protects against bisphenol A-induced female reproductive abnormalities in mice which may be mediated via modulation of eosinophil migration,endometrial gland formation,and protein expressions associated with prostaglandins in the myometrium. 展开更多
关键词 Red seaweed Gracilaria changii Antioxidant Endocrine disruptor bisphenol A REPRODUCTION
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Functional graphene oxide nanosheets modified with cyclodextrins for removal of Bisphenol A from water
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作者 Zhi-Hao Chen Zhuang Liu +6 位作者 Lei Zhang Quan-Wei Cai Jia-Qi Hu Wei Wang Xiao-Jie Ju Rui Xie Liang-Yin Chu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第11期79-87,共9页
A novel type of functional graphene oxide nanosheets(GNs)modified with b-cyclodextrins(b-CDs)have been developed by coating dopamine-functionalized cyclodextrin(DACD)molecules on GNs for removing Bisphenol A(BPA)molec... A novel type of functional graphene oxide nanosheets(GNs)modified with b-cyclodextrins(b-CDs)have been developed by coating dopamine-functionalized cyclodextrin(DACD)molecules on GNs for removing Bisphenol A(BPA)molecules from water.The DACD molecules with both b-CD groups for achieving adsorption property and dopamine(DA)groups for achieving adhesion property are synthesized by grafting DA onto carboxymethyl-b-cyclodextrin(CmbCD).The proposed DACD molecules can be firmly coated on the surfaces of various inorganic and organic substrates.Due to the large specific surface area of GNs,DACD-coated GNs(DACD@GNs)are proposed for efficient adsorption separation of BPA molecules from water.Due to the host-gust complexation between the BPA molecules in water and b-CDs on DACD@GNs,the fabricated DACD@GNs exhibit excellent adsorption performances.The adsorption kinetics can be explained via the pseudo-second-order model effectively.The experimental adsorption capacity of DACD@GNs is 11.29 mg·g^(-1) for BPA.Furthermore,after the adsorption process,the DACD@GNs can be easily separated from aqueous solutions via vacuum filtration with porous membranes,and then regenerated by simply washing with ethanol.The proposed strategy in this study can be used for effectively functionalizing the surfaces of various substrates with functional b-CDs,which is highly promising in applications in the field of adsorption separations,especially water treatments. 展开更多
关键词 Adsorption separation b-Cyclodextrin bisphenol A Graphene oxide nanosheets DOPAMINE
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