This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The stu...This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The study particularly emphasizes the production of 99.5 w/w% tetrahydrofuran from the downstream product of 1,4-butanediol synthesis via diethyl maleate. Pro/II simulation software is utilized to explore various system configurations, including sieve trays, valve trays, and packed columns. Material and energy balances are performed to ascertain stream compositions and energy demands. The investigation encompasses the effects of column operating pressure on condenser and reboiler temperatures, as well as the implications of utility streams. A rigorous distillation model is employed to compare valve tray, sieve tray, and random packing (utilizing Norton Super Intalox) column designs by varying the number of trays, reflux ratio, and second distillation column pressure. Heat exchangers are integrated into the model, and their areas and utility flow rates are computed and integrated into the economic assessment. Economic analysis, guided by Net Present Value (NPV) calculations over a 20-year span, drives the selection of the most cost-effective design. Results demonstrate that while all designs are energy-efficient, the packed column system emerges as the most economical choice, offering a comprehensive framework for the separation process. Furthermore, optimal design configurations and operating conditions for both tray and packed column systems are outlined, providing valuable insights for industrial applications.展开更多
通过对1949年至今全国大豆(Glycine max L.)历史数据的整理,详细分析了各地区大豆产量、播种面积和单产变动规律、分布特征和波动周期,探讨了影响中国大豆生产的重要因素,建立了中国大豆单产预测模型(指数拟合曲线、线性拟合曲线和多项...通过对1949年至今全国大豆(Glycine max L.)历史数据的整理,详细分析了各地区大豆产量、播种面积和单产变动规律、分布特征和波动周期,探讨了影响中国大豆生产的重要因素,建立了中国大豆单产预测模型(指数拟合曲线、线性拟合曲线和多项式拟合曲线),对未来(2020—2035年)中国大豆产量进行展望。研究发现,中华人民共和国成立以来中国大豆产量的增加主要来自单产增长;与其他粮食品种相比,中国大豆生产表现出生产地区相对集中、产量波动频率高、波动周期短和波动幅度大的特点;预计2030年中国大豆产量将达0.25亿t,到2035年将增加至0.27亿t,低于美国、巴西等国家的产量水平,但远高于加拿大、澳大利亚以及印度等国家。展开更多
AIM： To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS： The effect of SCFAs on cytokine rel...AIM： To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS： The effect of SCFAs on cytokine release from human neutrophils was studied with EHSA. SCFA- dependent modulation of NF-κB reporter activity was assessed in the human colon adenocarcinoma cell line, Colo320DM. Finally, the effect of SCFAs on gene expression and cytokine release, measured with RT-PCR and ELISA, respectively, was studied in mouse colon organ cultures established from colitic mice. RESULTS： Acetate, propionate and butyrate at 30 mmol/L decreased LPS-stimulated TNFα release from neutrophils, without affecting IL-8 protein release. All SCFAs dose dependently inhibited NF-κB reporter activity in Colo320DM cells. Propionate dose-dependently suppressed IL-6 mRNA and protein release from colon organ cultures and comparative studies revealed that propionate and butyrate at 30 mmol/L caused a strong inhibition of immune-related gene expression, whereas acetate was less effective. A similar inhibition was achieved with the proteasome inhibitor MG-132, but not the p38 MAPK inhibitor SB203580. All SCFAs decreased IL-6 protein release from organ cultures. CONCLUSION： In the present study propionate and butyrate were equipotent, whereas acetate was less effective, at suppressing NF-κB reporter activity, immune-related gene expression and cytokine release in vitro. Our findings suggest that propionate and acetate, in addition to butyrate, could be useful in the treatment of inflammatory disorders, including IBD.展开更多
AIM: Esomeprazole, an oral S-form of omeprazole, has been a greater acid inhibitor over omeprazole in treating acid-related diseases. Only less published data is available to confirm its efficacy for Asian people. The...AIM: Esomeprazole, an oral S-form of omeprazole, has been a greater acid inhibitor over omeprazole in treating acid-related diseases. Only less published data is available to confirm its efficacy for Asian people. Therefore, a perspective, double-blind, randomized comparison of esomeprazole tablets 40 mg (Nexium(?)) vs omeprazole capsules 20 mg (Losec(?)) in treating Chinese subjects with erosive/ulcerative reflux esophagitis (EE) was conducted. METHODS: A total of 48 EE patients were enrolled and randomized into two treatment groups under 8-wk therapy: 25 receiving esomeprazole, while another 23 receiving omeprazole treatment. Finally, 44 completed the whole 8-wk therapy. RESULTS: The difference in healing EE between two groups was 22.7% (72.7% vs 50.0%), not reaching significant value (P = 0.204). The median of the first time needed in relieving heartburn sensation was 1 d for both groups and the remission rates for heartburn on the 1st d after treatment were 77.3% and 65%, respectively (NS). The scores of various reflux relieving symptoms evaluated either by patients or by investigators were not different. Regarding drug safety, 28% of esomeprazole group and 26.1% of omeprazole group reported at least one episode of adverse effects, while constipation and skin dryness were the common side effects in both groups (NS). CONCLUSION: Esomeprazole 40 mg is an effective and safe drug at least comparable to omeprazole in treating Chinese EE patients.展开更多
AIM To comprehensively evaluate mitochondrial(dys)function in preclinical models of nonalcoholic steatohepatitis(NASH).METHODS We utilized two readily available mouse models of nonalcoholic fatty liver disease(NAFLD)w...AIM To comprehensively evaluate mitochondrial(dys)function in preclinical models of nonalcoholic steatohepatitis(NASH).METHODS We utilized two readily available mouse models of nonalcoholic fatty liver disease(NAFLD)with or without progressive fibrosis:Lep^(ob)/Lep^(ob)(ob/ob)and FATZO mice on high trans-fat,high fructose and high cholesterol(AMLN)diet.Presence of NASH was assessed using immunohistochemical and pathological techniques,and gene expression profiling.Morphological features of mitochondria were assessed via transmission electron microscopy and immunofluorescence,and function was assessed by measuring oxidative capacity in primary hepatocytes,and respiratory control and proton leak in isolated mitochondria.Oxidative stress was measured by assessing activity and/or expression levels of Nrf1,Sod1,Sod2,catalase and 8-OHdG.RESULTS When challenged with AMLN diet for 12 wk,ob/ob and FATZO mice developed steatohepatitis in the presence of obesity and hyperinsulinemia.NASH development was associated with hepatic mitochondrial abnormalities,similar to those previously observed in humans,including mitochondrial accumulation and increased proton leak.AMLN diet also resulted in increased numbers of fragmented mitochondria in both strains of mice.Despite similar mitochondrial phenotypes,we found that ob/ob mice developed more advanced hepatic fibrosis.Activity of superoxide dismutase(SOD)was increased in ob/ob AMLN mice,whereas FATZO mice displayed increased catalase activity,irrespective of diet.Furthermore,8-OHd G,a marker of oxidative DNA damage,was significantly increased in ob/ob AMLN mice compared to FATZO AMLN mice.Therefore,antioxidant capacity reflected as the ratio of catalase:SOD activity was similar between FATZO and C57 BL6 J control mice,but significantly perturbed in ob/ob mice.CONCLUSION Oxidative stress,and/or the capacity to compensate for increased oxidative stress,in the setting of mitochondrial dysfunction,is a key factor for development of hepatic injury and fibrosis in these mouse models.展开更多
Fibroblast growth factor （FGF） receptor substrate 2a （FRS2α） is the main mediator of signaling in the FGF pathway. Recent studies have shown that mitogen-activated protein kinase （MAPK） phosphorylates serine an...Fibroblast growth factor （FGF） receptor substrate 2a （FRS2α） is the main mediator of signaling in the FGF pathway. Recent studies have shown that mitogen-activated protein kinase （MAPK） phosphorylates serine and threonine residues in FRS2, negatively affecting FGF-induced tyrosine phosphorylation （PY） of FRS2. Several kinds of stimuli can induce serine/threonine phosphorylation （PS/T） of FRS2, indicating that FRS2 may be useful for studying crosstalk between growth factor signaling pathways. Here, we report that FGF-induced PY of FRS2 can be attenuated by EGF co-stimulation in PC12cells; this inhibitory effect could be completely reversed by U0126, an inhibitor of MEK. We further identified the ERK1/2-binding motif in FRS2 and generated FRS2-3KL, a mutant lacking MAPK binding and PT upon FGF and/or EGF stimulation. Unlike wild-type （WT） FRS2, FGF-induced PY of FRS2-3KL could not be inhibited by EGF co-stimulation, and FRS2-3KL-expressing PC12 cells exhibited more differentiating potential than FRS2-WT-expressing cells in response to FGF treatment. These results suggest that PS/T of FRS2 mediated by the FRS2-MAPK negative regulatory loop may function as a molecular switch integrating negative regulatory signals from other pathways into FGFR-generated signal transduction.展开更多
Objective： To evaluate the association between p53 codon 72 polymorphism （R72P） and the risk ofcolorectal liver metastases. Methods： The p53 R72P genotype was identified by polymerase chain reaction-restriction fr...Objective： To evaluate the association between p53 codon 72 polymorphism （R72P） and the risk ofcolorectal liver metastases. Methods： The p53 R72P genotype was identified by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method in 78 consecutive colorectal cancer patients with liver metastases and 214 age- and sex-matched cases with nonmetastatic colorectal cancer. Results： The R allele of the p53 R72P polymorphism was more frequently found in metastatic cases than in nonmetastatic cases （P=0.075）. Carriers of the 72R allele had a 2.25-fold （95% CI （confidence interval）=1.05-4.83） increased risk of liver metastases. On the stratification analysis, 72R-carrying genotype conferred a 3.46-fold （95% CI=1.02-11.72） and a 1.05-fold （95% CI=0.36-3.08） increased risk of liver metastases for p53 overexpression-positive and negative colorectal cancers, respectively. Conclusion： These results demonstrate for the first time that the 72R allele of the p53 polymorphism has an increased risk for liver metastases in colorectal cancers positive for p53 overexpression.展开更多
文摘This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The study particularly emphasizes the production of 99.5 w/w% tetrahydrofuran from the downstream product of 1,4-butanediol synthesis via diethyl maleate. Pro/II simulation software is utilized to explore various system configurations, including sieve trays, valve trays, and packed columns. Material and energy balances are performed to ascertain stream compositions and energy demands. The investigation encompasses the effects of column operating pressure on condenser and reboiler temperatures, as well as the implications of utility streams. A rigorous distillation model is employed to compare valve tray, sieve tray, and random packing (utilizing Norton Super Intalox) column designs by varying the number of trays, reflux ratio, and second distillation column pressure. Heat exchangers are integrated into the model, and their areas and utility flow rates are computed and integrated into the economic assessment. Economic analysis, guided by Net Present Value (NPV) calculations over a 20-year span, drives the selection of the most cost-effective design. Results demonstrate that while all designs are energy-efficient, the packed column system emerges as the most economical choice, offering a comprehensive framework for the separation process. Furthermore, optimal design configurations and operating conditions for both tray and packed column systems are outlined, providing valuable insights for industrial applications.
文摘通过对1949年至今全国大豆(Glycine max L.)历史数据的整理,详细分析了各地区大豆产量、播种面积和单产变动规律、分布特征和波动周期,探讨了影响中国大豆生产的重要因素,建立了中国大豆单产预测模型(指数拟合曲线、线性拟合曲线和多项式拟合曲线),对未来(2020—2035年)中国大豆产量进行展望。研究发现,中华人民共和国成立以来中国大豆产量的增加主要来自单产增长;与其他粮食品种相比,中国大豆生产表现出生产地区相对集中、产量波动频率高、波动周期短和波动幅度大的特点;预计2030年中国大豆产量将达0.25亿t,到2035年将增加至0.27亿t,低于美国、巴西等国家的产量水平,但远高于加拿大、澳大利亚以及印度等国家。
文摘AIM： To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS： The effect of SCFAs on cytokine release from human neutrophils was studied with EHSA. SCFA- dependent modulation of NF-κB reporter activity was assessed in the human colon adenocarcinoma cell line, Colo320DM. Finally, the effect of SCFAs on gene expression and cytokine release, measured with RT-PCR and ELISA, respectively, was studied in mouse colon organ cultures established from colitic mice. RESULTS： Acetate, propionate and butyrate at 30 mmol/L decreased LPS-stimulated TNFα release from neutrophils, without affecting IL-8 protein release. All SCFAs dose dependently inhibited NF-κB reporter activity in Colo320DM cells. Propionate dose-dependently suppressed IL-6 mRNA and protein release from colon organ cultures and comparative studies revealed that propionate and butyrate at 30 mmol/L caused a strong inhibition of immune-related gene expression, whereas acetate was less effective. A similar inhibition was achieved with the proteasome inhibitor MG-132, but not the p38 MAPK inhibitor SB203580. All SCFAs decreased IL-6 protein release from organ cultures. CONCLUSION： In the present study propionate and butyrate were equipotent, whereas acetate was less effective, at suppressing NF-κB reporter activity, immune-related gene expression and cytokine release in vitro. Our findings suggest that propionate and acetate, in addition to butyrate, could be useful in the treatment of inflammatory disorders, including IBD.
基金Supported by the Research Foundation of Digestive Medicine,Taiwan, China
文摘AIM: Esomeprazole, an oral S-form of omeprazole, has been a greater acid inhibitor over omeprazole in treating acid-related diseases. Only less published data is available to confirm its efficacy for Asian people. Therefore, a perspective, double-blind, randomized comparison of esomeprazole tablets 40 mg (Nexium(?)) vs omeprazole capsules 20 mg (Losec(?)) in treating Chinese subjects with erosive/ulcerative reflux esophagitis (EE) was conducted. METHODS: A total of 48 EE patients were enrolled and randomized into two treatment groups under 8-wk therapy: 25 receiving esomeprazole, while another 23 receiving omeprazole treatment. Finally, 44 completed the whole 8-wk therapy. RESULTS: The difference in healing EE between two groups was 22.7% (72.7% vs 50.0%), not reaching significant value (P = 0.204). The median of the first time needed in relieving heartburn sensation was 1 d for both groups and the remission rates for heartburn on the 1st d after treatment were 77.3% and 65%, respectively (NS). The scores of various reflux relieving symptoms evaluated either by patients or by investigators were not different. Regarding drug safety, 28% of esomeprazole group and 26.1% of omeprazole group reported at least one episode of adverse effects, while constipation and skin dryness were the common side effects in both groups (NS). CONCLUSION: Esomeprazole 40 mg is an effective and safe drug at least comparable to omeprazole in treating Chinese EE patients.
文摘AIM To comprehensively evaluate mitochondrial(dys)function in preclinical models of nonalcoholic steatohepatitis(NASH).METHODS We utilized two readily available mouse models of nonalcoholic fatty liver disease(NAFLD)with or without progressive fibrosis:Lep^(ob)/Lep^(ob)(ob/ob)and FATZO mice on high trans-fat,high fructose and high cholesterol(AMLN)diet.Presence of NASH was assessed using immunohistochemical and pathological techniques,and gene expression profiling.Morphological features of mitochondria were assessed via transmission electron microscopy and immunofluorescence,and function was assessed by measuring oxidative capacity in primary hepatocytes,and respiratory control and proton leak in isolated mitochondria.Oxidative stress was measured by assessing activity and/or expression levels of Nrf1,Sod1,Sod2,catalase and 8-OHdG.RESULTS When challenged with AMLN diet for 12 wk,ob/ob and FATZO mice developed steatohepatitis in the presence of obesity and hyperinsulinemia.NASH development was associated with hepatic mitochondrial abnormalities,similar to those previously observed in humans,including mitochondrial accumulation and increased proton leak.AMLN diet also resulted in increased numbers of fragmented mitochondria in both strains of mice.Despite similar mitochondrial phenotypes,we found that ob/ob mice developed more advanced hepatic fibrosis.Activity of superoxide dismutase(SOD)was increased in ob/ob AMLN mice,whereas FATZO mice displayed increased catalase activity,irrespective of diet.Furthermore,8-OHd G,a marker of oxidative DNA damage,was significantly increased in ob/ob AMLN mice compared to FATZO AMLN mice.Therefore,antioxidant capacity reflected as the ratio of catalase:SOD activity was similar between FATZO and C57 BL6 J control mice,but significantly perturbed in ob/ob mice.CONCLUSION Oxidative stress,and/or the capacity to compensate for increased oxidative stress,in the setting of mitochondrial dysfunction,is a key factor for development of hepatic injury and fibrosis in these mouse models.
文摘Fibroblast growth factor （FGF） receptor substrate 2a （FRS2α） is the main mediator of signaling in the FGF pathway. Recent studies have shown that mitogen-activated protein kinase （MAPK） phosphorylates serine and threonine residues in FRS2, negatively affecting FGF-induced tyrosine phosphorylation （PY） of FRS2. Several kinds of stimuli can induce serine/threonine phosphorylation （PS/T） of FRS2, indicating that FRS2 may be useful for studying crosstalk between growth factor signaling pathways. Here, we report that FGF-induced PY of FRS2 can be attenuated by EGF co-stimulation in PC12cells; this inhibitory effect could be completely reversed by U0126, an inhibitor of MEK. We further identified the ERK1/2-binding motif in FRS2 and generated FRS2-3KL, a mutant lacking MAPK binding and PT upon FGF and/or EGF stimulation. Unlike wild-type （WT） FRS2, FGF-induced PY of FRS2-3KL could not be inhibited by EGF co-stimulation, and FRS2-3KL-expressing PC12 cells exhibited more differentiating potential than FRS2-WT-expressing cells in response to FGF treatment. These results suggest that PS/T of FRS2 mediated by the FRS2-MAPK negative regulatory loop may function as a molecular switch integrating negative regulatory signals from other pathways into FGFR-generated signal transduction.
基金Project supported by the National Natural Science Foundation of China (No. 30470791) the Medical Science and Technology Research Foundation for the 11th Five-Year Program of People's Liberation Army, Nanjing Branch, China (No. 06MA27)
文摘Objective： To evaluate the association between p53 codon 72 polymorphism （R72P） and the risk ofcolorectal liver metastases. Methods： The p53 R72P genotype was identified by polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method in 78 consecutive colorectal cancer patients with liver metastases and 214 age- and sex-matched cases with nonmetastatic colorectal cancer. Results： The R allele of the p53 R72P polymorphism was more frequently found in metastatic cases than in nonmetastatic cases （P=0.075）. Carriers of the 72R allele had a 2.25-fold （95% CI （confidence interval）=1.05-4.83） increased risk of liver metastases. On the stratification analysis, 72R-carrying genotype conferred a 3.46-fold （95% CI=1.02-11.72） and a 1.05-fold （95% CI=0.36-3.08） increased risk of liver metastases for p53 overexpression-positive and negative colorectal cancers, respectively. Conclusion： These results demonstrate for the first time that the 72R allele of the p53 polymorphism has an increased risk for liver metastases in colorectal cancers positive for p53 overexpression.
