Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was c...Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate stability.The yellow‒brown soil from the Three Gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2,3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression analysis.The results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of acidity.Moreover,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate stability.The wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest influence.The soil aggregate stability is significantly correlated with the pH,Ca^(2+),Mg^(2+),maximum disintegration index(MDI)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggregate stability is primarily influenced by SBD,Ca^(2+),and MDI.These results offer a scientific basis for understanding the soil aggregate breakdown mechanism and are helpful for clarifying the coupled effect of wetting-drying cycles and acid rain on terrestrial ecosystems in the TGRA.展开更多
Ellagic acid(EA)is a natural antioxidant,widely present in a lot of forms’soft fruits,nuts,and other plant tissues,and helpful for promoting human health;however,its protective effect on postharvest fruit and improvi...Ellagic acid(EA)is a natural antioxidant,widely present in a lot of forms’soft fruits,nuts,and other plant tissues,and helpful for promoting human health;however,its protective effect on postharvest fruit and improving the quality index of postharvest fruit have rarely been studied.In this experiment,the strawberries were soaked in 0,100,200,300,400,and 500 mg L^(−1) EA,respectively,and the influential EA on fruit quality and the antioxidant system of strawberries were studied.Compared with the control,EA treatment can reduce the browning degree and rotting rate of strawberry fruit during storage and augment the soluble solid content(SSC).EA treatment can also increase the content of related stuff and enzyme activity in antioxidant systems;the gene expression level of polyphenol oxidase(PPO)in strawberries treated with EA was always down-regulated,correspondingly,the expression of other antioxidant enzyme genes was enhanced.Among the strawberry fruits treated with EA of different concentrations,300 mg L^(−1) EA had the best effect in the process of strawberry preservation.The results suggested that the proper concentration of exogenous EA at 300 mg L−1 could maintain strawberries’quality and enhance the antioxidant system by improving the activities of antioxidative enzymes and the ascorbateglutathione(AsA-GSH)cycle during storage.展开更多
Background: Methylmalonic aciduria (MMA) is a genetic disorder of aminoacid metabolism, due to mutations in methylmalonyl-CoA mutase, which leads to the accumulation of methylmalonic acid in body fluids. Patients typi...Background: Methylmalonic aciduria (MMA) is a genetic disorder of aminoacid metabolism, due to mutations in methylmalonyl-CoA mutase, which leads to the accumulation of methylmalonic acid in body fluids. Patients typically present at the age of 1 month to 1 year with dehydration, renal impairment as well as neurologic manifestations viz. seizure, encephalopathy, strokes and disease in the globus pallidi. The case: a 26-year-old man presented with severe acute on top of chronic renal disease with serum creatinine at 590 umol/L and bilateral 8 cm kidneys with thin and echogenic cortex. He had: (a) hypernatremic dehydration, metabolic acidosis and high ammonia level with (b) a history of multiple similar attacks since the age of 8 months. Diagnosis of MMA was confirmed by high serum and urine enzymatic levels as well as genetic testing. His initial management included support with replacements of fluids, electrolytes, and bicarbonates as well as intravenous dextrose, vitamin B12 and broad-spectrum antibiotic (Meropenem) for his chest infection. Subsequently, he received 1) CARBAGLU (carglumic acid) for 7 days to lower his ammonia level to Conclusion: Untreated homozygous MMA variants, can achieve adulthood with significant renal disease yet their morbidity and mortality can be ameliorated with diet and specific therapy.展开更多
Lift cycle assessment(LCA)methodology was applied to evaluating and comparing two waste acid disposal processes in zinc smelting.The results indicate that environmental impacts of gas−liquid vulcanization technologies...Lift cycle assessment(LCA)methodology was applied to evaluating and comparing two waste acid disposal processes in zinc smelting.The results indicate that environmental impacts of gas−liquid vulcanization technologies are human toxicity,abiotic depletion potential,and global warming risk,which are mainly caused in neutralizing−evaporating−crystallization unit and electrodialysis unit.As for traditional lime neutralization method,vulcanization unit is the main factor.In this regard,the total environmental impact of traditional lime neutralization method is much higher than that of gas−liquid vulcanization technologies.Furthermore,the sensitive analysis shows that electricity and sodium sulfide(60%)are sensitive factors in two waste acid disposal technologies.In addition,the total cost of disposing a functional unit waste acid in traditional lime neutralization process is nearly 27 times that of the gas−liquid vulcanization waste acid disposal technologies.展开更多
From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive c...From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive cycle and environment conditions(e.g.,temperature and food availability).Histological analysis as well as lipid and fatty acid analyses were performed on neutral and polar lipids of the gonad.Results showed that gametogenesis occurred in winter and spring at the expense of lipids previously accumulated in summer and autumn,whereas spawning occurred in summer(20.4-24.6℃).The seasonal variation in lipid content was similar to that of the mean oocyte diameter.In both neutral and polar lipids,the 20:5n-3 and 22:6n-3 levels were relatively higher than saturated fatty acids,and polyunsaturated fatty acids were abundant,with series n-3 as the predominant component.Seasonal variations in the 20:5n-3 and 22:6n-3 levels and the principal n-3 fatty acids were clearly related to the reproductive cycle.The ∑(n-3) and ∑(n-6) values were relatively high during January-May,and the associated unsaturation index was significantly higher than that in other months.The results suggest that fatty acids play an important role in the gametogenesis of F.mutica.展开更多
There is an urgent need to elucidate the pathogenesis of myocardial ischemia(MI)and potential drug treatments.Here,the anti-MI mechanism and material basis of Ginkgo biloba L.extract(GBE)were studied from the perspect...There is an urgent need to elucidate the pathogenesis of myocardial ischemia(MI)and potential drug treatments.Here,the anti-MI mechanism and material basis of Ginkgo biloba L.extract(GBE)were studied from the perspective of energy metabolism flux regulation.Metabolic flux analysis(MFA)was performed to investigate energy metabolism flux disorder and the regulatory nodes of GBE components in isoproterenol(ISO)-induced ischemia-like cardiomyocytes.It showed that[U-13 C]glucose derived m+2 isotopologues from the upstream tricarboxylic acid(TCA)cycle metabolites were markedly accumulated in ISO-injured cardiomyocytes,but the opposite was seen for the downstream metabolites,while their total cellular concentrations were increased.This indicates a blockage of carbon flow from glycolysis and enhanced anaplerosis from other carbon sources.A Seahorse test was used to screen for GBE components with regulatory effects on mitochondrial aerobic respiratory dysfunction.It showed that bilobalide protected against impaired mitochondrial aerobic respiration.MFA also showed that bilobalide significantly modulated the TCA cycle flux,reduced abnormal metabolite accumulation,and balanced the demand of different carbon sources.Western blotting and PCR analysis showed that bilobalide decreased the enhanced expression of key metabolic enzymes in injured cells.Bilobalide’s efficacy was verified by in vivo experiments in rats.This is the first report to show that bilobalide,the active ingredient of GBE,protects against MI by rescuing impaired TCA cycle flux.This provides a new mechanism and potential drug treatment for MI.It also shows the potential of MFA/Seahorse combination as a powerful strategy for pharmacological research on herbal medicine.展开更多
CO2 fixation pathway of Caminibacter profundus, a chemolithoautotrophic e-Proteobacteria from deep-sea hydrothermal vent, was determined and characterized by genetic and enzymatic analyses. Gene expression of key enzy...CO2 fixation pathway of Caminibacter profundus, a chemolithoautotrophic e-Proteobacteria from deep-sea hydrothermal vent, was determined and characterized by genetic and enzymatic analyses. Gene expression of key enzymes for CO2 fixation in response to salinity, pH and O2 in Medium 829 were also investigated. The results demonstrate that C. profundus contained aclB, porA and oorA, the genes encoding key enzymes of reductive tricarboxylic acid （rTCA） cycle. However, genes fragments of cbbL and cbbMencoding key enzyme of Calvin cycle were not recovered. Key enzymatic activities of ATP citrate lyase （ACL）, pyruvate： ferredoxin oxidoreductase （POR） and 2-oxoglutarate： ferredoxin oxidoreductase （OOR） were also present in C. profun- dus. The combination of genetic and enzymatic analyses confirm that C. profundus adopted rTCA cycle for carbon assimilation. The results of aclB and oorA relative expressions of C. profundus demonstrate that the ranges of environmental factors for high genes expression were sea salt 3.0%-5.0% （optimum 3.0%）, pH 5.0-6.5（optimum pH 6.5）, anaerobic to microaerobic conditions （optimum 1.0% 02）. Gene expression pat- terns under different conditions show similar patterns with bacterial growth, revealing that key rTCA cycle genes provided molecular basis for bacterial growth and propagation. Our results suggest that C. profun- dus could regulate key genes of rTCA cycle for carbon assimilation and energy metabolism in response to environmental fluctuations in hydrothermal vent.展开更多
AIM: To determine the effect of cis -9, trans -11-conjugated linoleic acid (c9, t11-CLA) on the cell cycle of gastric cancer cells (SGC-7901) and its possible mechanism in inhibition cancer growth. METHODS: Using cell...AIM: To determine the effect of cis -9, trans -11-conjugated linoleic acid (c9, t11-CLA) on the cell cycle of gastric cancer cells (SGC-7901) and its possible mechanism in inhibition cancer growth. METHODS: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B(1), D(1), p16(ink4a) and p21(cip/waf1) of SGC-7901 cells which were treated with various c9, t11-CLA concentrations (25, 50, 100 and 200 micromol.L(-1))of c 9, t 11-CLA for 24 and 48h, with a negative control (0.1% ethane). RESULTS: The cell growth and DNA synthesis of SGC-7901 cells were inhibited by c9, t11-CLA.SGC-7901 cells. Eight day after treatment with various concentrations of c9, t11-CLA mentioned above, the inhibition rates were 5.92%, 20.15%, 75.61% and 82.44%, respectively and inhibitory effect of c9, t11-CLA on DNA synthesis (except for 25 micromol.L, 24h) showed significantly less (3)H-TdR incorporation than that in the negative controls (P【0.05 and P【0.01). Immunocytochemical staining demonstrated that SGC-7901 cells preincubated in media supplemented with different c9, t11-CLA concentrations at various times significantly decreased the expressions of PCNA (the expression rates were 7.2-3.0%, 24h and 9.1-0.9% at 48h, respectively), Cyclin A (11.0-2.3%, 24h and 8.5-0.5%,48h), B(1) (4.8-1.8% at 24h and 5.5-0.6% at 48h)and D(1) (3.6-1.4% at 24h and 3.7%-0 at 48h) as compared with those in the negative controls(the expressions of PCNA, Cyclin A, B(1) and D(1) were 6.5% at 24h and 9.0% at 48h, 4.2% at 24h and 5.1% at 48h, 9.5% at 24h and 6.0% at 48h,respectively)(P【0.01), whereas the expressions of P16(ink4a) and P21(cip/waf1), cyclin-dependent kinases inhibitors(CDKI), were increased. CONCLUSION: The cell growth and proliferation of SGC-7901 cell is inhibited by c9, t11-CLA via blocking the cell cycle, with reduced expressions of cyclin A,B(1) and D(1) and enhanced expressions of CDKI(P16(ink4a) and p21(cip/waf1)).展开更多
HCC(Hepatocellular Carcinoma)is a critical health issue worldwide.Our previous animal experiment has confirmed that blueberry malvidin-3-galactoside(M3G)can regulate the progression of HCC.In this study,feces samples ...HCC(Hepatocellular Carcinoma)is a critical health issue worldwide.Our previous animal experiment has confirmed that blueberry malvidin-3-galactoside(M3G)can regulate the progression of HCC.In this study,feces samples from the same batch of mice were collected to explore the regulatory mechanism of M3G on intestinal microbiota and microbial TCA cycle metabolism KEGG pathway in HCC mice based on 16S rRNA sequencing and metagenomics.Our results showed that blueberry M3G increased the microbial diversity and regulated the structure of intestinal microbiota in mice,such as increasing the abundance of Clostridia(butyric acid-producing bacteria),Oscillospira and Ruminococcus,and reducing the abundance of pathogenic Erysipelotrichi.Compared with the group of liver cancer and 5-fluorouracil,blueberry M3G significantly regulated microbial TCA cycle KEGG pathway via improving the expression of key proteins(porA,DLAT,aceE,PC and OGDH).Additionally,we found which the abundance of Muribaculum intestinale increased by blueberry M3G may be an important factor affecting the microbial TCA cycle KEGG pathway via the pearson correlation(R)analysis of protein and microbiota.Taken together,these results demonstrate that the blueberry M3G has the potential to be an intestinal microbiota regulator and an adjuvant to HCC therapy.展开更多
Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell ...Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1).展开更多
The influence of arsenate and phosphate on the growth and respiration of 21 days old seedlings in two cultivars of rice, viz., IR64 and Nayanmani was studied. As arsenate and phosphate are similar in their chemical co...The influence of arsenate and phosphate on the growth and respiration of 21 days old seedlings in two cultivars of rice, viz., IR64 and Nayanmani was studied. As arsenate and phosphate are similar in their chemical configuration and the latter is preferentially taken up by the phosphate transporters, it results in a competitive inhibition of arsenate uptake in presence of phosphate. Increasing concentrations of sodium arsenate (25 μM, 50 μM and 100 μM) hindered the growth in both the cultivars, with cv. IR64 being more severely affected than cv. Nayanmani. There was an elevation in the levels of organic acids measured in both the cultivars, accompanied by a reduction in the activities of the dehydrogenases of the TCA cycle, viz., pyruvate dehydrogenase, isocitrate dehydrogenase, succinate dehydrogenase and malate dedrogenase under arsenic treatment alone. Also, an elevation in the activities of citrate synthase and fumarase enzymes was noticed in both test seedlings with increasing concentrations of arsenic. These alterations were more prominent in cv. IR64 than in cv. Nayanmani. On joint application of phosphate along with arsenate, amelioration of the toxic effects of arsenate was observed to some extent, resulting in an overall revival of respiration leading to improved growth and metabolism.展开更多
AIM: To investigate the growth effects of 4-phenyl butyric acid (PBA) on human gastric carcinoma cells and their mechanisms. METHODS: Moderately-differentiated human gastric carcinoma SGC-7901 and lowly-differentiated...AIM: To investigate the growth effects of 4-phenyl butyric acid (PBA) on human gastric carcinoma cells and their mechanisms. METHODS: Moderately-differentiated human gastric carcinoma SGC-7901 and lowly-differentiated MGC-803 cells were treated with 5, 10, 20, 40, and 60 μmol/L PBA for 1-4 d. Cell proliferation was detected using the MTT colorimetric assay. Cell cycle distributions were examined using flow cytometry.RESULTS: The proliferation of gastric carcinoma cells was inhibited by PBA in a doseand time-dependent fashion. Flow cytometry showed that SGC-7901 cells treated with low concentrations of PBA were arrested at the G0/G1 phase, whereas cells treated with high concentrations of PBA were arrested at the G2/M phase. Although MGC-803 cells treated with low concentrations of PBA were also arrested at the G0/G1 phase, cells treated with high concentrations of PBA were arrested at the S phase. CONCLUSION: The growth inhibitory effect of PBA on gastric cancer cells is associated with alteration of the cell cycle. For moderately-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and G2/M phases. For lowly-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and S phases.展开更多
Objective: To study the protective effect of ascorbic acid and curcumin against the abnormal estrous cycle and morphological changes in cells induced by repeated ultraviolet B(UVB)radiation in female Wistar rats.Metho...Objective: To study the protective effect of ascorbic acid and curcumin against the abnormal estrous cycle and morphological changes in cells induced by repeated ultraviolet B(UVB)radiation in female Wistar rats.Methods: Sixteen female sexually mature Wistar rats weighing 130-150 g and aged 12-16 weeks were randomly divided into four groups.The control group received normal food and water ad libitum.The UVB group was exposed to a dose of 280 nm of UVB radiation for 2 h daily.The UVB+curcumin group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of curcumin(25 mg/kg body weight)daily.The UVB+ascorbic acid group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of ascorbic acid(250 mg/kg body weight)daily.All the treatments last for 15 consecutive days.Body and ovary weight and gonadosomatic index were measured.The stages(proestrus,estrus,metaestrus and diestrus)of the estrous cycle were determined by the cell types observed in the vaginal smear.Results: UVB radiation caused irregular alterations on the estrous cycle and morphological changes of the female Wistar rat as compared with the control group.Ascorbic acid and curcumin protected UVB-induced estrous phases and their cells.But curcumin showed greater protection than ascorbic acid.Conclusions: Ascorbic acid and curcumin at low doses can alleviate abnormal estrous cycle and morphological changes in cells induced by UVB radiations in female Wistar rats.展开更多
Background:Numerous questions regarding metabolism alterations in endometrial cancer remain unanswered.Methods:We used the Mann-Whitney test to identify significantly downregulated genes in Cluster II,which were then ...Background:Numerous questions regarding metabolism alterations in endometrial cancer remain unanswered.Methods:We used the Mann-Whitney test to identify significantly downregulated genes in Cluster II,which were then subject to Ingenuity Pathway Analysis and Gene Ontology(GO)enrichment analysis.We next compared the expression levels of several key enzymes between the CTNNB1 mutant and wide-type patients to correlate“TCA Cycle”alterations with CTNNB1 mutation status.Finally,we performed a Spearman correlation between the TCA Cycle genes and the immune checkpoint molecule to understand the relationship between TCA Cycle dysfunction and immune response.All statistical tests were two-sided.Results:A total of 603 genes were significantly downregulated in Cluster II.Pathway analysis showed that metabolic pathways were frequently dysregulated,and GO analysis demonstrated that metabolic processes were commonly retarded.In particular,TCA Cycle is the most significantly altered metabolic pathway(P=1.45×10-07),with one-third of the enzymes altered.The TCA Cycle pathway activity and the expression levels of several key enzymes were significantly lower in CTNNB1 mutant patients,compared to CTNNB1 wide-type patients.In addition,the TCA Cycle pathway activity and the expression levels of pathway genes were significantly and positively correlated with PD-L1 gene expression.Conclusion:This study systematically characterizes a subset of endometrioid endometrial cancer patients with dysregulated TCA Cycle pathway,which may contribute to immune resistance in endometrial cancer.展开更多
Introduction: Polycystic ovarian syndrome (PCOS) is undoubtedly the commonest androgen disorder in woman’s fertile period and certainly one of the most prevalent causes of anovulation. The syndrome has an estimated p...Introduction: Polycystic ovarian syndrome (PCOS) is undoubtedly the commonest androgen disorder in woman’s fertile period and certainly one of the most prevalent causes of anovulation. The syndrome has an estimated prevalence of 4% - 10% among women of childbearing age. Previously, our group demonstrated the effect of gonadal white adipose tissue transplantation from wild-type lean and fertile female mice to isogenic obese anovulatory ob/ob mice. These complex metabolic interrelationships between obesity and PCOS have yet to be fully understood. The aim of this study was to evaluate the effect of gonadal white adipose tissue (WAT) transplantation from the wild-type lean and fertile female mice to isogenic obese, anovulatory mice (Lep ob/Lep ob) on the expression of glycolysis- and TCA cycle-related genes and obtain a general view of the glucose metabolism in the brain of these animals. Methods: Fifteen ob/ob mice ranging from 2 to 3 months of age were divided into 3 experimental groups: control normal weight (n = 5), obese control (n = 5) and obese 7 days leptin treated (n = 5). The whole brains of the mice were processed for RNA extraction. The samples from each group were used to perform PCR assays using an array plate containing 84 primers to study the glucose metabolism-related genes. Results: The glycolysis- and TCA cycle-related genes were significantly downregulated. The most significantly affected genes were as follows: for glycolysis (fold regulation with p < 0.05):Pgm1,Bpgm,Aldob, andEno3 (119, 45, 18, and 28 times less, respectively);and for the TCA cycle (fold regulation with p < 0.05):Cs,Idh3b, andMdh2 (84, 27, and 37 times less, respectively).Conclusion: The seven-day leptin treated mice show a decrease in the glucose metabolism. These results confirm the ability of the adipose tissue-derived hormone leptin to regulate early crucial genes that are related to glycolysis mechanisms and to the TCA cycle. This hormone seems to revert early the central physiological conditions that are associated with PCOS;however, the morphological alterations can only be observed within a 45-day treatment.展开更多
Background and Objective Lung cancer is the rst killer of human being in the whole world. Recently, although many treatment strategies have been developed, the anti-cancer effects
基金co-funded by the National Natural Science Foundation of China(U204020742277323)+2 种基金the 111 Project of Hubei Province(2021EJD026)the open fund of Key Laboratory of Geological Hazards on Three Gorges Reservoir Area(China Three Gorges University)Ministry of Education(2022KDZ24).
文摘Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate stability.The yellow‒brown soil from the Three Gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2,3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression analysis.The results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of acidity.Moreover,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate stability.The wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest influence.The soil aggregate stability is significantly correlated with the pH,Ca^(2+),Mg^(2+),maximum disintegration index(MDI)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggregate stability is primarily influenced by SBD,Ca^(2+),and MDI.These results offer a scientific basis for understanding the soil aggregate breakdown mechanism and are helpful for clarifying the coupled effect of wetting-drying cycles and acid rain on terrestrial ecosystems in the TGRA.
基金the National Natural Science Foundation of China,Grant Number 31800581.
文摘Ellagic acid(EA)is a natural antioxidant,widely present in a lot of forms’soft fruits,nuts,and other plant tissues,and helpful for promoting human health;however,its protective effect on postharvest fruit and improving the quality index of postharvest fruit have rarely been studied.In this experiment,the strawberries were soaked in 0,100,200,300,400,and 500 mg L^(−1) EA,respectively,and the influential EA on fruit quality and the antioxidant system of strawberries were studied.Compared with the control,EA treatment can reduce the browning degree and rotting rate of strawberry fruit during storage and augment the soluble solid content(SSC).EA treatment can also increase the content of related stuff and enzyme activity in antioxidant systems;the gene expression level of polyphenol oxidase(PPO)in strawberries treated with EA was always down-regulated,correspondingly,the expression of other antioxidant enzyme genes was enhanced.Among the strawberry fruits treated with EA of different concentrations,300 mg L^(−1) EA had the best effect in the process of strawberry preservation.The results suggested that the proper concentration of exogenous EA at 300 mg L−1 could maintain strawberries’quality and enhance the antioxidant system by improving the activities of antioxidative enzymes and the ascorbateglutathione(AsA-GSH)cycle during storage.
文摘Background: Methylmalonic aciduria (MMA) is a genetic disorder of aminoacid metabolism, due to mutations in methylmalonyl-CoA mutase, which leads to the accumulation of methylmalonic acid in body fluids. Patients typically present at the age of 1 month to 1 year with dehydration, renal impairment as well as neurologic manifestations viz. seizure, encephalopathy, strokes and disease in the globus pallidi. The case: a 26-year-old man presented with severe acute on top of chronic renal disease with serum creatinine at 590 umol/L and bilateral 8 cm kidneys with thin and echogenic cortex. He had: (a) hypernatremic dehydration, metabolic acidosis and high ammonia level with (b) a history of multiple similar attacks since the age of 8 months. Diagnosis of MMA was confirmed by high serum and urine enzymatic levels as well as genetic testing. His initial management included support with replacements of fluids, electrolytes, and bicarbonates as well as intravenous dextrose, vitamin B12 and broad-spectrum antibiotic (Meropenem) for his chest infection. Subsequently, he received 1) CARBAGLU (carglumic acid) for 7 days to lower his ammonia level to Conclusion: Untreated homozygous MMA variants, can achieve adulthood with significant renal disease yet their morbidity and mortality can be ameliorated with diet and specific therapy.
基金the National Key R&D Program of China(Nos.2018YFC1903304,2019YFC1907405)National Natural Science Foundation of China(No.51904354).
文摘Lift cycle assessment(LCA)methodology was applied to evaluating and comparing two waste acid disposal processes in zinc smelting.The results indicate that environmental impacts of gas−liquid vulcanization technologies are human toxicity,abiotic depletion potential,and global warming risk,which are mainly caused in neutralizing−evaporating−crystallization unit and electrodialysis unit.As for traditional lime neutralization method,vulcanization unit is the main factor.In this regard,the total environmental impact of traditional lime neutralization method is much higher than that of gas−liquid vulcanization technologies.Furthermore,the sensitive analysis shows that electricity and sodium sulfide(60%)are sensitive factors in two waste acid disposal technologies.In addition,the total cost of disposing a functional unit waste acid in traditional lime neutralization process is nearly 27 times that of the gas−liquid vulcanization waste acid disposal technologies.
基金the National Marine Public Welfare Research Program(201205023)the Scientific and Technical Supporting Program(2011BAD13B03)
文摘From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive cycle and environment conditions(e.g.,temperature and food availability).Histological analysis as well as lipid and fatty acid analyses were performed on neutral and polar lipids of the gonad.Results showed that gametogenesis occurred in winter and spring at the expense of lipids previously accumulated in summer and autumn,whereas spawning occurred in summer(20.4-24.6℃).The seasonal variation in lipid content was similar to that of the mean oocyte diameter.In both neutral and polar lipids,the 20:5n-3 and 22:6n-3 levels were relatively higher than saturated fatty acids,and polyunsaturated fatty acids were abundant,with series n-3 as the predominant component.Seasonal variations in the 20:5n-3 and 22:6n-3 levels and the principal n-3 fatty acids were clearly related to the reproductive cycle.The ∑(n-3) and ∑(n-6) values were relatively high during January-May,and the associated unsaturation index was significantly higher than that in other months.The results suggest that fatty acids play an important role in the gametogenesis of F.mutica.
基金supported by grants from the National Natural Science Foundation of China(Grant No.:81803496)the CAMS Innovation Fund for Medical Sciences(Grant No.:2016-I2M-3-016)the Applications and Core Technology University Research(ACT-UR,Grant No.:4084)。
文摘There is an urgent need to elucidate the pathogenesis of myocardial ischemia(MI)and potential drug treatments.Here,the anti-MI mechanism and material basis of Ginkgo biloba L.extract(GBE)were studied from the perspective of energy metabolism flux regulation.Metabolic flux analysis(MFA)was performed to investigate energy metabolism flux disorder and the regulatory nodes of GBE components in isoproterenol(ISO)-induced ischemia-like cardiomyocytes.It showed that[U-13 C]glucose derived m+2 isotopologues from the upstream tricarboxylic acid(TCA)cycle metabolites were markedly accumulated in ISO-injured cardiomyocytes,but the opposite was seen for the downstream metabolites,while their total cellular concentrations were increased.This indicates a blockage of carbon flow from glycolysis and enhanced anaplerosis from other carbon sources.A Seahorse test was used to screen for GBE components with regulatory effects on mitochondrial aerobic respiratory dysfunction.It showed that bilobalide protected against impaired mitochondrial aerobic respiration.MFA also showed that bilobalide significantly modulated the TCA cycle flux,reduced abnormal metabolite accumulation,and balanced the demand of different carbon sources.Western blotting and PCR analysis showed that bilobalide decreased the enhanced expression of key metabolic enzymes in injured cells.Bilobalide’s efficacy was verified by in vivo experiments in rats.This is the first report to show that bilobalide,the active ingredient of GBE,protects against MI by rescuing impaired TCA cycle flux.This provides a new mechanism and potential drug treatment for MI.It also shows the potential of MFA/Seahorse combination as a powerful strategy for pharmacological research on herbal medicine.
基金China Ocean Mineral Resources R&D Association under contract No. DYXM-115-02-2-19Basic Scientific Fund for National Public Research Institutes of China under contract No. 2011T04
文摘CO2 fixation pathway of Caminibacter profundus, a chemolithoautotrophic e-Proteobacteria from deep-sea hydrothermal vent, was determined and characterized by genetic and enzymatic analyses. Gene expression of key enzymes for CO2 fixation in response to salinity, pH and O2 in Medium 829 were also investigated. The results demonstrate that C. profundus contained aclB, porA and oorA, the genes encoding key enzymes of reductive tricarboxylic acid （rTCA） cycle. However, genes fragments of cbbL and cbbMencoding key enzyme of Calvin cycle were not recovered. Key enzymatic activities of ATP citrate lyase （ACL）, pyruvate： ferredoxin oxidoreductase （POR） and 2-oxoglutarate： ferredoxin oxidoreductase （OOR） were also present in C. profun- dus. The combination of genetic and enzymatic analyses confirm that C. profundus adopted rTCA cycle for carbon assimilation. The results of aclB and oorA relative expressions of C. profundus demonstrate that the ranges of environmental factors for high genes expression were sea salt 3.0%-5.0% （optimum 3.0%）, pH 5.0-6.5（optimum pH 6.5）, anaerobic to microaerobic conditions （optimum 1.0% 02）. Gene expression pat- terns under different conditions show similar patterns with bacterial growth, revealing that key rTCA cycle genes provided molecular basis for bacterial growth and propagation. Our results suggest that C. profun- dus could regulate key genes of rTCA cycle for carbon assimilation and energy metabolism in response to environmental fluctuations in hydrothermal vent.
基金the National Natural Science Foundation of China,No.39870661
文摘AIM: To determine the effect of cis -9, trans -11-conjugated linoleic acid (c9, t11-CLA) on the cell cycle of gastric cancer cells (SGC-7901) and its possible mechanism in inhibition cancer growth. METHODS: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B(1), D(1), p16(ink4a) and p21(cip/waf1) of SGC-7901 cells which were treated with various c9, t11-CLA concentrations (25, 50, 100 and 200 micromol.L(-1))of c 9, t 11-CLA for 24 and 48h, with a negative control (0.1% ethane). RESULTS: The cell growth and DNA synthesis of SGC-7901 cells were inhibited by c9, t11-CLA.SGC-7901 cells. Eight day after treatment with various concentrations of c9, t11-CLA mentioned above, the inhibition rates were 5.92%, 20.15%, 75.61% and 82.44%, respectively and inhibitory effect of c9, t11-CLA on DNA synthesis (except for 25 micromol.L, 24h) showed significantly less (3)H-TdR incorporation than that in the negative controls (P【0.05 and P【0.01). Immunocytochemical staining demonstrated that SGC-7901 cells preincubated in media supplemented with different c9, t11-CLA concentrations at various times significantly decreased the expressions of PCNA (the expression rates were 7.2-3.0%, 24h and 9.1-0.9% at 48h, respectively), Cyclin A (11.0-2.3%, 24h and 8.5-0.5%,48h), B(1) (4.8-1.8% at 24h and 5.5-0.6% at 48h)and D(1) (3.6-1.4% at 24h and 3.7%-0 at 48h) as compared with those in the negative controls(the expressions of PCNA, Cyclin A, B(1) and D(1) were 6.5% at 24h and 9.0% at 48h, 4.2% at 24h and 5.1% at 48h, 9.5% at 24h and 6.0% at 48h,respectively)(P【0.01), whereas the expressions of P16(ink4a) and P21(cip/waf1), cyclin-dependent kinases inhibitors(CDKI), were increased. CONCLUSION: The cell growth and proliferation of SGC-7901 cell is inhibited by c9, t11-CLA via blocking the cell cycle, with reduced expressions of cyclin A,B(1) and D(1) and enhanced expressions of CDKI(P16(ink4a) and p21(cip/waf1)).
基金supported by the National Natural Science Foundation of China(31972090)LiaoNing Revitalization Talents Program(XLYC1807127)+3 种基金Liaoning BaiQianWan Talents Program(2018-B-21)Tianzhu Mountain Scholar Support Project(2018)the Innovative Talent Support Program for Institution of Higher Learning of Liaoning Province(LR2017038)the project of“double hundred”for major scientific and technological achievements transformating of Shenyang Science and Technology Bureau(Z19-3-012).
文摘HCC(Hepatocellular Carcinoma)is a critical health issue worldwide.Our previous animal experiment has confirmed that blueberry malvidin-3-galactoside(M3G)can regulate the progression of HCC.In this study,feces samples from the same batch of mice were collected to explore the regulatory mechanism of M3G on intestinal microbiota and microbial TCA cycle metabolism KEGG pathway in HCC mice based on 16S rRNA sequencing and metagenomics.Our results showed that blueberry M3G increased the microbial diversity and regulated the structure of intestinal microbiota in mice,such as increasing the abundance of Clostridia(butyric acid-producing bacteria),Oscillospira and Ruminococcus,and reducing the abundance of pathogenic Erysipelotrichi.Compared with the group of liver cancer and 5-fluorouracil,blueberry M3G significantly regulated microbial TCA cycle KEGG pathway via improving the expression of key proteins(porA,DLAT,aceE,PC and OGDH).Additionally,we found which the abundance of Muribaculum intestinale increased by blueberry M3G may be an important factor affecting the microbial TCA cycle KEGG pathway via the pearson correlation(R)analysis of protein and microbiota.Taken together,these results demonstrate that the blueberry M3G has the potential to be an intestinal microbiota regulator and an adjuvant to HCC therapy.
基金This work was supported by the National Natural Science Foundation of China(No.39870661). Phone: (0086-451)-3641309 Fax: (0086-451)-3641253
文摘Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1).
文摘The influence of arsenate and phosphate on the growth and respiration of 21 days old seedlings in two cultivars of rice, viz., IR64 and Nayanmani was studied. As arsenate and phosphate are similar in their chemical configuration and the latter is preferentially taken up by the phosphate transporters, it results in a competitive inhibition of arsenate uptake in presence of phosphate. Increasing concentrations of sodium arsenate (25 μM, 50 μM and 100 μM) hindered the growth in both the cultivars, with cv. IR64 being more severely affected than cv. Nayanmani. There was an elevation in the levels of organic acids measured in both the cultivars, accompanied by a reduction in the activities of the dehydrogenases of the TCA cycle, viz., pyruvate dehydrogenase, isocitrate dehydrogenase, succinate dehydrogenase and malate dedrogenase under arsenic treatment alone. Also, an elevation in the activities of citrate synthase and fumarase enzymes was noticed in both test seedlings with increasing concentrations of arsenic. These alterations were more prominent in cv. IR64 than in cv. Nayanmani. On joint application of phosphate along with arsenate, amelioration of the toxic effects of arsenate was observed to some extent, resulting in an overall revival of respiration leading to improved growth and metabolism.
基金Supported by Natural Science Foundation of Ningbo, No. 2009A610134Natural Sciences Foundation of Zhejiang, No. Y207244+3 种基金College Students’ Science-Technology Innovation Program of Zhejiang Province, No. 200959the Excellent Disser-tation Foundation of Ningbo University, No. 201014KC Wong Magna Fund of Ningbo Universitythe Scientific Innovation Team Project of Ningbo, No.2011B82014
文摘AIM: To investigate the growth effects of 4-phenyl butyric acid (PBA) on human gastric carcinoma cells and their mechanisms. METHODS: Moderately-differentiated human gastric carcinoma SGC-7901 and lowly-differentiated MGC-803 cells were treated with 5, 10, 20, 40, and 60 μmol/L PBA for 1-4 d. Cell proliferation was detected using the MTT colorimetric assay. Cell cycle distributions were examined using flow cytometry.RESULTS: The proliferation of gastric carcinoma cells was inhibited by PBA in a doseand time-dependent fashion. Flow cytometry showed that SGC-7901 cells treated with low concentrations of PBA were arrested at the G0/G1 phase, whereas cells treated with high concentrations of PBA were arrested at the G2/M phase. Although MGC-803 cells treated with low concentrations of PBA were also arrested at the G0/G1 phase, cells treated with high concentrations of PBA were arrested at the S phase. CONCLUSION: The growth inhibitory effect of PBA on gastric cancer cells is associated with alteration of the cell cycle. For moderately-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and G2/M phases. For lowly-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and S phases.
文摘Objective: To study the protective effect of ascorbic acid and curcumin against the abnormal estrous cycle and morphological changes in cells induced by repeated ultraviolet B(UVB)radiation in female Wistar rats.Methods: Sixteen female sexually mature Wistar rats weighing 130-150 g and aged 12-16 weeks were randomly divided into four groups.The control group received normal food and water ad libitum.The UVB group was exposed to a dose of 280 nm of UVB radiation for 2 h daily.The UVB+curcumin group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of curcumin(25 mg/kg body weight)daily.The UVB+ascorbic acid group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of ascorbic acid(250 mg/kg body weight)daily.All the treatments last for 15 consecutive days.Body and ovary weight and gonadosomatic index were measured.The stages(proestrus,estrus,metaestrus and diestrus)of the estrous cycle were determined by the cell types observed in the vaginal smear.Results: UVB radiation caused irregular alterations on the estrous cycle and morphological changes of the female Wistar rat as compared with the control group.Ascorbic acid and curcumin protected UVB-induced estrous phases and their cells.But curcumin showed greater protection than ascorbic acid.Conclusions: Ascorbic acid and curcumin at low doses can alleviate abnormal estrous cycle and morphological changes in cells induced by UVB radiations in female Wistar rats.
文摘Background:Numerous questions regarding metabolism alterations in endometrial cancer remain unanswered.Methods:We used the Mann-Whitney test to identify significantly downregulated genes in Cluster II,which were then subject to Ingenuity Pathway Analysis and Gene Ontology(GO)enrichment analysis.We next compared the expression levels of several key enzymes between the CTNNB1 mutant and wide-type patients to correlate“TCA Cycle”alterations with CTNNB1 mutation status.Finally,we performed a Spearman correlation between the TCA Cycle genes and the immune checkpoint molecule to understand the relationship between TCA Cycle dysfunction and immune response.All statistical tests were two-sided.Results:A total of 603 genes were significantly downregulated in Cluster II.Pathway analysis showed that metabolic pathways were frequently dysregulated,and GO analysis demonstrated that metabolic processes were commonly retarded.In particular,TCA Cycle is the most significantly altered metabolic pathway(P=1.45×10-07),with one-third of the enzymes altered.The TCA Cycle pathway activity and the expression levels of several key enzymes were significantly lower in CTNNB1 mutant patients,compared to CTNNB1 wide-type patients.In addition,the TCA Cycle pathway activity and the expression levels of pathway genes were significantly and positively correlated with PD-L1 gene expression.Conclusion:This study systematically characterizes a subset of endometrioid endometrial cancer patients with dysregulated TCA Cycle pathway,which may contribute to immune resistance in endometrial cancer.
文摘Introduction: Polycystic ovarian syndrome (PCOS) is undoubtedly the commonest androgen disorder in woman’s fertile period and certainly one of the most prevalent causes of anovulation. The syndrome has an estimated prevalence of 4% - 10% among women of childbearing age. Previously, our group demonstrated the effect of gonadal white adipose tissue transplantation from wild-type lean and fertile female mice to isogenic obese anovulatory ob/ob mice. These complex metabolic interrelationships between obesity and PCOS have yet to be fully understood. The aim of this study was to evaluate the effect of gonadal white adipose tissue (WAT) transplantation from the wild-type lean and fertile female mice to isogenic obese, anovulatory mice (Lep ob/Lep ob) on the expression of glycolysis- and TCA cycle-related genes and obtain a general view of the glucose metabolism in the brain of these animals. Methods: Fifteen ob/ob mice ranging from 2 to 3 months of age were divided into 3 experimental groups: control normal weight (n = 5), obese control (n = 5) and obese 7 days leptin treated (n = 5). The whole brains of the mice were processed for RNA extraction. The samples from each group were used to perform PCR assays using an array plate containing 84 primers to study the glucose metabolism-related genes. Results: The glycolysis- and TCA cycle-related genes were significantly downregulated. The most significantly affected genes were as follows: for glycolysis (fold regulation with p < 0.05):Pgm1,Bpgm,Aldob, andEno3 (119, 45, 18, and 28 times less, respectively);and for the TCA cycle (fold regulation with p < 0.05):Cs,Idh3b, andMdh2 (84, 27, and 37 times less, respectively).Conclusion: The seven-day leptin treated mice show a decrease in the glucose metabolism. These results confirm the ability of the adipose tissue-derived hormone leptin to regulate early crucial genes that are related to glycolysis mechanisms and to the TCA cycle. This hormone seems to revert early the central physiological conditions that are associated with PCOS;however, the morphological alterations can only be observed within a 45-day treatment.
基金supported by a grant from the key project of the National Natural Science Foundation of China (to Qinghua ZHOU)(No. 30430300)National Natural Science Foundation of China (to Qinghua ZHOU)(No. 30670922)INTERNATION Scienc and Techniquie COOPRATION PROGRAM OF CHINA (ISCP) (to Qinghua ZHOU)(No.2006DFB32330)
文摘Background and Objective Lung cancer is the rst killer of human being in the whole world. Recently, although many treatment strategies have been developed, the anti-cancer effects
