Using the Widdel medium with extracted microcystin(MC)as the sole carbon and nitrogen sources,the MC-degrading bacteria community S_6 was enriched from the sediment of Litopenaeus vannamei pond,and a novel MC-degradin...Using the Widdel medium with extracted microcystin(MC)as the sole carbon and nitrogen sources,the MC-degrading bacteria community S_6 was enriched from the sediment of Litopenaeus vannamei pond,and a novel MC-degrading bacteria strain was isolated from S_6.According to 16S rDNA gene sequence and biochemical characteristics,the isolated strain was identified and named Nitratireductor aquimarinus D_(1).Fulvic acid(FA),as a widely existing photosensitizer involved in MC photodegradation,coexists with MC-degrading bacteria in natural water.The synergistic effects of N.aquimarinus D_(1) and FA on MC degradation were evaluated via comparing the degradation rate of MC induced by N.aquimarinus D_(1) and FA alone and in combination under natural light conditions.Compared with the control group,the supplementation of N.aquimarinus D_(1) and FA alone or in combination could significantly increase the degradation rate of MC(P<0.05).In the first 36 h,the degradation effect of FA on MC was better than that of N.aquimarinus D_(1),but the degradation effect was opposite at 48 h.N.aquimarinus D_(1) and FA did not show synergistic effect on MC degradation until 48 h.In the application of N.aquimarinus and FA to degrade MC in aquaculture pond,there might be a time-lag effect in the synergistic degradation.展开更多
Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In thi...Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.展开更多
Objective To evaluate magnetic resonance (MR) Imaging and 1 H magnetic resonance spectroscopy (1 HMRS) in the study of normal biochemical process of the brain, as well as differentiation of normal senile brain from ce...Objective To evaluate magnetic resonance (MR) Imaging and 1 H magnetic resonance spectroscopy (1 HMRS) in the study of normal biochemical process of the brain, as well as differentiation of normal senile brain from cerebral diseases related to senility. Methods One hundred and eighty healthy adult volunteers were selected for MR examination and 60 other healthy subjects for 1 HMRS examination. Ages of subjects ranged from 18 to 80 years. They were divided into six age groups. A 0.35 T superconductive MR system was used to perform MR examination. Point resolved spectroscopy sequence was required for 1 HMRS. The metabolites in the spectra included: N-acetylaspartate (NAA), choline compounds (CHO), creatine compounds (CR), myo-inositol (MI), glutamate and glutamine (Glu-n). Results In 180 cases of MR, the shortest T2 relaxation time occurred in the deep gray matter within the same age group while the length of T1 relaxation time was ordered from low to high compared to age groups. T2 relaxation time decreased as age increased. The peaks, ordered from high to low, were as follows in 60 cases of 1 HMRS: NAA, CR, CHO, MI, Glu-n. The ratios of NAA/CR and Glu-n/CR were higher in the senile age group, while that of MI/CR was lower. The ratio of CHO/CR was increased as age decreased. The ratio of NAA/CR and MI/CR gradually decreased in relation to movement from the anterior to the posterior part of the brain; the ratio of CHO/CR was highest in the occipital cortex. Correlation of T1 relaxation time and partial metabolite ratios to age were present in gray matter.Conclusions Quantitative studies of MR T1 and T2 relaxation times and 1 HMRS are essential to evaluation of normal myelinization processes, neuronal integrity and age-related biochemical changes in the brain.展开更多
Objective: To investigate the anti-tumor effect of procyanidin (WeiMaiNing, WMN) on a murine Lewis lung carcinoma cell line (3LL) and the influence on the cell cycle. Methods: The inhibitory rate of 3LL growth was det...Objective: To investigate the anti-tumor effect of procyanidin (WeiMaiNing, WMN) on a murine Lewis lung carcinoma cell line (3LL) and the influence on the cell cycle. Methods: The inhibitory rate of 3LL growth was detected in the model of murine Lewis lung carcinoma. The effect of the drug on 3LL cell cycle and the influence of the drug on the expression of cyclin D1 protein were investigated by flow cytometry, immunohistochemical staining. Results: The inhibitory rates of WMN in 3LL were 19.14%, 33.59% and 51.56% respectively at dosages 100 mg穔g-1穌-1, 150 mg穔g-1穌-1 and 250 mg穔g-1穌-1. The inhibitory effect was in a dose-dependent manner. We found WMN significantly increased (P<0.01) the number of 3LL cells in G0-G1 phase (35.97% vs. 27.2% at 150 mg穔g-1穌-1 WMN; 40.10% vs. 27.2% at 250 mg穔g-1穌-1 WMN) and decreased the expression of cyclin D1, PCNA protein. Conclusion: WeiMaiNing inhibits the growth of 3LL cells in vivo by decreasing the expression of PCNA and cyclin D1, blocking the cells in G0-G1 phase and preventing the cells transition from G1 to S phase while DNA is replicated.展开更多
Homogenization treatment under an electric field increases the distributive homogeneity of the T1 precipitation and improves the yield strength of 2091 Al-Li alloy.
C NMR spin-lattice relaxation times (T1), line widths, nuclear Overhauser effects (NOE) at room temperature have been measured for radiated ets 1,4-polybutadiene.With the increase of radiation dose T1 is almost invari...C NMR spin-lattice relaxation times (T1), line widths, nuclear Overhauser effects (NOE) at room temperature have been measured for radiated ets 1,4-polybutadiene.With the increase of radiation dose T1 is almost invariant, but line width of the methylene (-CH2-) carbon increases remarkably, and its NOE factor decreases sharply. This implies that the long-range segmental motion is hindered, and saturated tertiary carbon (-C H- ) is formed during crosslinking of ets 1,4-polybutadiene.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.32172978,31772857)the Natural Science Foundation of Tianjin(No.22JCYBJC00430)+2 种基金the Tianjin Science and Technology Planning Project(No.22ZYCGSN00050)the Fundamental Research Funds of Tianjin Universities(Nos.2020ZD06,2021KJ110)the Gansu Science and Technology Project(Nos.21CX6NP223,2023ZZ1NC006)。
文摘Using the Widdel medium with extracted microcystin(MC)as the sole carbon and nitrogen sources,the MC-degrading bacteria community S_6 was enriched from the sediment of Litopenaeus vannamei pond,and a novel MC-degrading bacteria strain was isolated from S_6.According to 16S rDNA gene sequence and biochemical characteristics,the isolated strain was identified and named Nitratireductor aquimarinus D_(1).Fulvic acid(FA),as a widely existing photosensitizer involved in MC photodegradation,coexists with MC-degrading bacteria in natural water.The synergistic effects of N.aquimarinus D_(1) and FA on MC degradation were evaluated via comparing the degradation rate of MC induced by N.aquimarinus D_(1) and FA alone and in combination under natural light conditions.Compared with the control group,the supplementation of N.aquimarinus D_(1) and FA alone or in combination could significantly increase the degradation rate of MC(P<0.05).In the first 36 h,the degradation effect of FA on MC was better than that of N.aquimarinus D_(1),but the degradation effect was opposite at 48 h.N.aquimarinus D_(1) and FA did not show synergistic effect on MC degradation until 48 h.In the application of N.aquimarinus and FA to degrade MC in aquaculture pond,there might be a time-lag effect in the synergistic degradation.
基金supported by the project from National Natural Science Foundation of China (31671962)Fundamental Research Funds for the Central Universities (2662019PY034)。
文摘Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.
文摘Objective To evaluate magnetic resonance (MR) Imaging and 1 H magnetic resonance spectroscopy (1 HMRS) in the study of normal biochemical process of the brain, as well as differentiation of normal senile brain from cerebral diseases related to senility. Methods One hundred and eighty healthy adult volunteers were selected for MR examination and 60 other healthy subjects for 1 HMRS examination. Ages of subjects ranged from 18 to 80 years. They were divided into six age groups. A 0.35 T superconductive MR system was used to perform MR examination. Point resolved spectroscopy sequence was required for 1 HMRS. The metabolites in the spectra included: N-acetylaspartate (NAA), choline compounds (CHO), creatine compounds (CR), myo-inositol (MI), glutamate and glutamine (Glu-n). Results In 180 cases of MR, the shortest T2 relaxation time occurred in the deep gray matter within the same age group while the length of T1 relaxation time was ordered from low to high compared to age groups. T2 relaxation time decreased as age increased. The peaks, ordered from high to low, were as follows in 60 cases of 1 HMRS: NAA, CR, CHO, MI, Glu-n. The ratios of NAA/CR and Glu-n/CR were higher in the senile age group, while that of MI/CR was lower. The ratio of CHO/CR was increased as age decreased. The ratio of NAA/CR and MI/CR gradually decreased in relation to movement from the anterior to the posterior part of the brain; the ratio of CHO/CR was highest in the occipital cortex. Correlation of T1 relaxation time and partial metabolite ratios to age were present in gray matter.Conclusions Quantitative studies of MR T1 and T2 relaxation times and 1 HMRS are essential to evaluation of normal myelinization processes, neuronal integrity and age-related biochemical changes in the brain.
文摘Objective: To investigate the anti-tumor effect of procyanidin (WeiMaiNing, WMN) on a murine Lewis lung carcinoma cell line (3LL) and the influence on the cell cycle. Methods: The inhibitory rate of 3LL growth was detected in the model of murine Lewis lung carcinoma. The effect of the drug on 3LL cell cycle and the influence of the drug on the expression of cyclin D1 protein were investigated by flow cytometry, immunohistochemical staining. Results: The inhibitory rates of WMN in 3LL were 19.14%, 33.59% and 51.56% respectively at dosages 100 mg穔g-1穌-1, 150 mg穔g-1穌-1 and 250 mg穔g-1穌-1. The inhibitory effect was in a dose-dependent manner. We found WMN significantly increased (P<0.01) the number of 3LL cells in G0-G1 phase (35.97% vs. 27.2% at 150 mg穔g-1穌-1 WMN; 40.10% vs. 27.2% at 250 mg穔g-1穌-1 WMN) and decreased the expression of cyclin D1, PCNA protein. Conclusion: WeiMaiNing inhibits the growth of 3LL cells in vivo by decreasing the expression of PCNA and cyclin D1, blocking the cells in G0-G1 phase and preventing the cells transition from G1 to S phase while DNA is replicated.
文摘Homogenization treatment under an electric field increases the distributive homogeneity of the T1 precipitation and improves the yield strength of 2091 Al-Li alloy.
文摘C NMR spin-lattice relaxation times (T1), line widths, nuclear Overhauser effects (NOE) at room temperature have been measured for radiated ets 1,4-polybutadiene.With the increase of radiation dose T1 is almost invariant, but line width of the methylene (-CH2-) carbon increases remarkably, and its NOE factor decreases sharply. This implies that the long-range segmental motion is hindered, and saturated tertiary carbon (-C H- ) is formed during crosslinking of ets 1,4-polybutadiene.