CO_(2) flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can...CO_(2) flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can also cause severe CO_(2) gas channeling problems.Therefore,anti-gas channeling is a necessary measure to improve the effect of CO_(2) flooding.The kind of anti-gas channeling refers to the plugging of fractures in the deep formation to prevent CO_(2) gas channeling,which is different from the wellbore leakage.Polymer microspheres have the characteristics of controllable deep plugging,which can achieve the profile control of low-permeability fractured reservoirs.In acidic environments with supercritical CO_(2),traditional polymer microspheres have poor expandability and plugging properties.Based on previous work,a systematic evaluation of the expansion performance,dispersion rheological properties,stability,deep migration,anti-CO_(2) channeling and enhanced oil recovery ability of a novel acid-resistant polymer microsphere(DCNPM-A)was carried out under CQ oilifield conditions(salinity of85,000 mg/L,80℃,pH=3).The results show that the DCNPM-A microsphere had a better expansion performance than the traditional microsphere,with a swelling rate of 13.5.The microsphere dispersion with a concentration of 0.1%-0.5%had the advantages of low viscosity,high dispersion and good injectability in the low permeability fractured core.In the acidic environment of supercritical CO_(2),DCNPM-A microspheres showed excellent stability and could maintain strength for over 60 d with less loss.In core experiments,DCNPM-A microspheres exhibited delayed swelling characteristics and could effectively plug deep formations.With a plugging rate of 95%,the subsequent enhanced oil recovery of CO_(2) flooding could reach 21.03%.The experimental results can provide a theoretical basis for anti-CO_(2)channeling and enhanced oil recovery in low-permeability fractured reservoirs.展开更多
With the prevalence of obesity and obesity-related metabolic syndrome,such as insulin resistance in recent years,it is urgent to explore effective interventions to prevent the progression of obesity-related metabolic ...With the prevalence of obesity and obesity-related metabolic syndrome,such as insulin resistance in recent years,it is urgent to explore effective interventions to prevent the progression of obesity-related metabolic syndrome.Palmitoleic acid is a monounsaturated fatty acid that is available from dietary sources,mainly derived from marine products.P almitoleic acid plays a positive role in maintaining glucose homeostasis and reducing inflammation.However,it is still unknow the mechanism of palmitoleic acid in ameliorating insulin resistance.Here,we investigated the effects of palmitoleic acid on chow diet(CD)-fed and high-fat diet(HFD)-fed mice,which were fed CD or HFD for 12 weeks before administration.We administrated mice with BSA(control),oleic acid,or palmitoleic acid for 6 weeks on top of CD or HFD feeding.We found that palmitoleic acid only improved glucose homeostasis in HFD-fed obese mice by increasing glucose clearance and reducing HOMA-IR.Further study explored that palmitoleic acid changed the composition of gut microbiota by decreasing Firmicutes population and increasing Bacteroidetes population.In colon,palmitoleic acid increased intestinal tight junction integrity and reduced inflammation.Moreover,palmitoleic acid decreased macrophage infiltration in liver and adipose tissue and increase glucose uptake in adipose tissue.Diacylglycerol(DAG)in tissue(for example,liver)is found to positively correlated with HOMA-IR.HFD enhanced the levels of DAGs in liver but not in adipose tissue in this study.Palmitoleic acid did not reverse the high DAG levels induced by HFD in liver.Therefore,in HFD-fed mice,palmitoleic acid reduced insulin resistance by an independent-manner of DAGs.It might be associated with the beneficial effects of palmitoleic acid on altering the gut microbiota composition,improving of intestinal barrier function,and downregulating the inflammation in colon,liver,and adipose tissue.展开更多
In this study,the effects of intermetallic compounds(Mg_(17)Al_(12)and Al_(8)Mn_(5))on the Mg-Al layered double hydroxide(LDH)formation mechanism and corrosion behavior of an in-situ LDH/Mg(OH)_(2)steam coatings on AZ...In this study,the effects of intermetallic compounds(Mg_(17)Al_(12)and Al_(8)Mn_(5))on the Mg-Al layered double hydroxide(LDH)formation mechanism and corrosion behavior of an in-situ LDH/Mg(OH)_(2)steam coatings on AZ80 Mg alloy were investigated.Citric acid(CA)was used to activate the alloy surface during the pretreatment process.The alloy was first pretreated with CA and then subjected to a hydrothermal process using ultrapure water to produce Mg-Al-LDH/Mg(OH)_(2)steam coating.The effect of different time of acid pretreatment on the activation of the intermetallic compounds was investigated.The microstructure and elemental composition of the obtained coatings were analyzed using FE-SEM,EDS,XRD and FT-IR.The corrosion resistance of the coated samples was evaluated using different techniques,i.e.,potentiodynamic polarization(PDP),electrochemical impedance spectrum(EIS)and hydrogen evolution test.The results indicated that the CA pretreatment significantly influenced the activity of the alloy surface by exposing the intermetallic compounds.The surface area fraction of Mg_(17)Al_(12)and Al_(8)Mn_(5)phases on the surface of the alloy was significantly higher after the CA pretreatment,and thus promoted the growth of the subsequent Mg-Al-LDH coatings.The CA pretreatment for 30 s resulted in a denser and thicker LDH coating.Increase in the CA pretreatment time significantly led to the improvement in corrosion resistance of the coated AZ80 alloy.The corrosion current density of the coated alloy was lower by three orders of magnitude as compared to the uncoated alloy.展开更多
Clubroot and herbicide resistance,high oleic acid(OA)content,and early maturity are targets of rapeseed(Brassica napus L.)breeding.The objective of this study was to develop new male-fertility restorer lines by pyrami...Clubroot and herbicide resistance,high oleic acid(OA)content,and early maturity are targets of rapeseed(Brassica napus L.)breeding.The objective of this study was to develop new male-fertility restorer lines by pyramiding favorable genes to improve these traits simultaneously.Seven elite alleles for the four traits were introduced into the restorer line 621R by speed breeding with marker-assisted and phenotypic selection.Six introgression lines(ILs)were developed with four-to seven-gene combinations and crossed with two elite parents to develop hybrids.All ILs and their corresponding hybrids displayed high resistance to both clubroot pathotype 4 and sulfonylurea herbicides.Three ILs and their hybrids showed large increases in OA contents and four showed earlier maturity.These new ILs may be useful in rapeseed hybrid breeding for the target traits.展开更多
We encapsulated vincristine into folic acid-conjugated PEGylated liposomes to improve the anti-tumor efficacy on multidrug resistant cancers.It was observed that the drug delivery system we constructed exhibited maxim...We encapsulated vincristine into folic acid-conjugated PEGylated liposomes to improve the anti-tumor efficacy on multidrug resistant cancers.It was observed that the drug delivery system we constructed exhibited maximum cytotoxicity on KBv200 cells(multidrug resistant variant)compared with any other formulations.The semi-quantitative analysis of region of interest revealed that there was a great increase in area under curve(AUC)of a near-infrared fluorescein in solid tumors due to folic acid-mediated accumulation.Folic acid-conjugated PEGylated liposomes showed a significant tumor growth inhibiting effect in vitro and in vivo.TUNEL assay revealed that folic acid-conjugated PEGylated liposomes could induce cell apoptosis much more greatly than others.This study demonstrated that it had potential application prospective for the treatment of multidrug resistant cancer.展开更多
Objective: To evaluate the insulin sensitivity action of ferulic acid(FA) in skeletal muscle and hypothalamus of high-fat diet(HFD)-induced obese mice. Methods: Obese mouse model was induced by HFD(45 kcal% lard fat) ...Objective: To evaluate the insulin sensitivity action of ferulic acid(FA) in skeletal muscle and hypothalamus of high-fat diet(HFD)-induced obese mice. Methods: Obese mouse model was induced by HFD(45 kcal% lard fat) for 16 weeks. After 8 weeks of HFD feeding, these obese mice were orally treated with FA at doses of 25 and 50 mg/kg/day for 8 weeks. At the end of all treatments, the epididymal fat, pancreas, skeletal muscle and hypothalamus were removed for biochemical parameter and protein expression examinations. Results: FA treatment significantly decreased leptin level in fat tissue and insulin level in pancreas(P < 0.05). Interestingly, obese mice treated with FA increased the protein expressions of insulin receptor substrate-1, phosphatidylinositol 3-kinase, and phosphorylated-protein kinase B in both muscle and brain(P < 0.05). The phosphorylations of adenosine monophosphate-activated protein kinase and acetyl-CoA carboxylase in muscle, and leptin receptor protein in hypothalamus were also increased(P < 0.05). The pancreatic islets histology showed smaller size in obese mice treated with FA compared to untreated obese mice. Conclusions: These findings indicate the beneficial effect of FA in improving insulin resistance in HFD-induced obese mice. These effects are probably mediated via modulating the insulin receptor substrate/phosphatidylinositol 3-kinase/protein kinase B or adenosine monophosphate-activated protein kinase pathways.展开更多
Objective:To explore the mechanism of drug resistance in acute lymphoblastic leukemia and the anti-tumor effect of combination therapy of dehydroabietic acid and vincristine against acute lymphoblastic leukemia cells....Objective:To explore the mechanism of drug resistance in acute lymphoblastic leukemia and the anti-tumor effect of combination therapy of dehydroabietic acid and vincristine against acute lymphoblastic leukemia cells.Methods:Acute lymphoblastic leukemia cells REH and CCRFCEM were employed to detect the anti-tumor effect of vincristine and doxorubicin on proliferation and apoptosis using EdU assay,human active caspase-3 Quantikine ELISA kit,and flow cytometry.Vincristine-resistant REH cells(REH-R),survivin knockdown and overexpressing REH cells were established to verify the role of survivin in drug resistance.Additionally,in vitro and in vivo assays were performed to determine the effect of dehydroabietic acid on the cytotoxicity of vincristine.Results:Vincristine and doxorubicin markedly suppressed proliferation and induced apoptosis of REH and CCRF-CEM cells.Survivin expression was upregulated in REH-R cells compared with REH cells.Knockdown of survivin expression obviously restored the sensitivity of REH-R cells to vincristine.Akt phosphorylation was also increased in REH-R cells compared to REH cells.In addition,LY294002,a PI3k/Akt pathway blocker,inhibited survivin expression and enhanced cytotoxicity of vincristine to REH-R cells.Dehydroabietic acid effectively reduced survivin expression in REH-R cells,thereby enhancing the therapeutic effect of vincristine on drug-resistant cells.Survivin overexpression markedly reduced the effect of dehydroabietic acid on enhancing the anti-proliferation and inducing apoptosis effect of vincristine.Moreover,the combination of dehydroabietic acid with vincristine significantly extended the survival rate in a mouse xenograft model of acute lymphoblastic leukemia,compared with vincristine treatment alone.Conclusions:Dehydroabietic acid may be used as a potential candidate for the treatment of acute lymphoblastic leukemia in combination with vincristine.展开更多
<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococ...<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococcus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> is reported severally to be resistant to the drugs often used empirically for treatment of urinary tract infections (UTIs). Their ability to exhibit resistance to multiple drugs is a great de</span><span style="font-family:Verdana;">al of threat to successes recorded in the management of UTIs cause</span><span style="font-family:Verdana;">d by this pathogen. Lactic acid bacteria (LAB) have been demonstrated to exhibit an</span><span style="font-family:Verdana;">timicrobial activities but studies about their prospect against multi</span><span style="font-family:Verdana;">-drug resistant </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> are quite few. This study therefore investigated acti</span><span><span style="font-family:Verdana;">vities of LAB against the multi-drug resistant </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> recover</span></span><span style="font-family:Verdana;">ed fro</span><span style="font-family:Verdana;">m urine samples of symptomatic women. The three differ</span><span style="font-family:Verdana;">ent species of LAB </span><span><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 62, </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 86 and </span><i><span style="font-family:Verdana;">Weis</span></i></span><i><span style="font-family:Verdana;">sella</span></i><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> BTA 40) previously isolated and identified by 16S rRNA s</span><span style="font-family:;" "=""><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;">quencing were selected based on their history of antimicrobial activities. Their</span><span style="font-family:Verdana;"> m</span><span style="font-family:Verdana;">etabolites were employed in the antagonistic assays against six (6) mu</span><span style="font-family:Verdana;">lti-drug resista</span><span style="font-family:Verdana;">nt test pathogens recovered fro</span><span style="font-family:Verdana;">m urine samples of symptomatic, non-pregnant women attending clinics in Lagos, Nigeria and the control (</span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> subs bovis strain DSM 18669) following standard procedures. </span><span style="font-family:Verdana;">The pathogens showed resistances to almost all the antibiotics except</span><span style="font-family:Verdana;"> levofloxaci</span><span style="font-family:Verdana;">n, ciprofloxacin, imipenem while the control showed resistance to thr</span><span style="font-family:Verdana;">ee. The LAB, </span><i><span style="font-family:Verdana;">L.</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> inhibited five (83.3%) of the pathogens with zone diameter of 12 - 17 mm, followed by </span><i><span style="font-family:Verdana;">W</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> inhibiting three (50%) with 15 - 17 mm. </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> on the other hand, inhibited a pathogen and the control with zones of 13 mm and 14 mm respectively. In conclusion, the extracted metabolites of LAB inhibited the growth of multi-drug resistant clinical isolates of uropathogenic </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> and may therefore be potent alternatives to antibiotics.</span></span>展开更多
The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely ac...The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.展开更多
Objective To evaluate the synergy of the Burkholderia signaling molecule cis-2-dodecenoic acid(BDSF) and fluconazole(FLU) or itraconazole(ITRA) against two azole-resistant C. albicans clinical isolates in vitro and in...Objective To evaluate the synergy of the Burkholderia signaling molecule cis-2-dodecenoic acid(BDSF) and fluconazole(FLU) or itraconazole(ITRA) against two azole-resistant C. albicans clinical isolates in vitro and in vivo. Methods Minimum inhibitory concentrations(MICs) of antibiotics against two azole-resistant C. albicans were measured by the checkerboard technique, E-test, and time-kill assay. In vivo antifungal synergy testing was performed on mice. Analysis of the relative gene expression levels of the strains was conducted by quantitative reverse-transcription polymerase chain reaction(qR T-PCR). Results BDSF showed highly synergistic effects in combination with FLU or ITRA with a fractional inhibitory concentration index of ≤ 0.08. BDSF was not cytotoxic to normal human foreskin fibroblast cells at concentrations of up to 300 μg/mL. The qR T-PCR results showed that the combination of BDSF and FLU/ITRA significantly inhibits the expression of the efflux pump genes CDR1 and MDR1 via suppression of the transcription factors TAC1 and MRR1, respectively, when compared with FLU or ITRA alone. No dramatic difference in the mR NA expression levels of ERG1, ERG11, and UPC2 was found, which indicates that the drug combinations do not significantly interfere with UPC2-mediated ergosterol levels. In vivo experiments revealed that combination therapy can be an effective therapeutic approach to treat candidiasis. Conclusion The synergistic effects of BDSF and azoles may be useful as an alternative approach to control azole-resistant Candida infections.展开更多
Chemotherapy plays a crucial role in triple-negative breast cancer (TNBC) treatment as it not only directly kills cancer cells but also induces immunogenic cell death. However, the chemotherapeutic efficacy was strong...Chemotherapy plays a crucial role in triple-negative breast cancer (TNBC) treatment as it not only directly kills cancer cells but also induces immunogenic cell death. However, the chemotherapeutic efficacy was strongly restricted by the acidic and hypoxic tumor environment. Herein, we have successfully formulated PLGA-based nanoparticles concurrently loaded with doxorubicin (DOX), hemoglobin (Hb) and CaCO3 by a CaCO3-assisted emulsion method, aiming at the effective treatment of TNBC. We found that the obtained nanomedicine (DHCaNPs) exhibited effective drug encapsulation and pH-responsive drug release behavior. Moreover, DHCaNPs demonstrated robust capabilities in neutralizing protons and oxygen transport. Consequently, DHCaNPs could not only serve as oxygen nanoshuttles to attenuate tumor hypoxia but also neutralize the acidic tumor microenvironment (TME) by depleting lactic acid, thereby effectively overcoming the resistance to chemotherapy. Furthermore, DHCaNPs demonstrated a notable ability to enhance antitumor immune responses by increasing the frequency of tumor-infiltrating effector lymphocytes and reducing the frequency of various immune-suppressive cells, therefore exhibiting a superior efficacy in suppressing tumor growth and metastasis when combined with anti-PD-L1 (αPD-L1) immunotherapy. In summary, this study highlights that DHCaNPs could effectively attenuate the acidic and hypoxic TME, offering a promising strategy to figure out an enhanced chemo-immunotherapy to benefit TNBC patients.展开更多
Block copolymer polystyrene-b-poly(acrylic acid)(PS-b-PAA) was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtaine...Block copolymer polystyrene-b-poly(acrylic acid)(PS-b-PAA) was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtained. Acid resistant properties of this type of hybrid CaCO3 were studied. Size measurement shows that the acid resistant properties of the hybrid particles are different in different solutions, such as HCl, EDTA, and H2SO4 solutions.展开更多
BACKGROUND Lingguizhugan(LGZG)decoction is a widely used classic Chinese medicine formula that was recently shown to improve high-fat diet(HFD)-induced insulin resistance(IR)in animal studies.AIM To assess the therape...BACKGROUND Lingguizhugan(LGZG)decoction is a widely used classic Chinese medicine formula that was recently shown to improve high-fat diet(HFD)-induced insulin resistance(IR)in animal studies.AIM To assess the therapeutic effect of LGZG decoction on HFD-induced IR and explore the potential underlying mechanism.METHODS To establish an IR rat model,a 12-wk HFD was administered,followed by a 4-wk treatment with LGZG.The determination of IR status was achieved through the use of biochemical tests and oral glucose tolerance tests.Using a targeted metabolomics platform to analyze changes in serum metabolites,quantitative real-time PCR(qRT-PCR)was used to assess the gene expression of the ribosomal protein S6 kinase beta 1(S6K1).RESULTS In IR rats,LGZG decreased body weight and indices of hepatic steatosis.It effectively controlled blood glucose and food intake while protecting islet cells.Metabolite analysis revealed significant differences between the HFD and HFDLGZG groups.LGZG intervention reduced branched-chain amino acid levels.Levels of IR-related metabolites such as tryptophan,alanine,taurine,and asparagine decreased significantly.IR may be linked to amino acids due to the contemporaneous increase in S6K1 expression,as shown by qRT-PCR.CONCLUSIONS Our study strongly suggests that LGZG decoction reduces HFD-induced IR.LGZG may activate S6K1 via metabolic pathways.These findings lay the groundwork for the potential of LGZG as an IR treatment.展开更多
The soil in Guangxi has been severely acidified,restricting sustainable development of agriculture.In this paper,based on the screening of organic fertilizer additives,a method for the production of acidification-resi...The soil in Guangxi has been severely acidified,restricting sustainable development of agriculture.In this paper,based on the screening of organic fertilizer additives,a method for the production of acidification-resistant organic fertilizer specific for acid red soil improvement was proposed,and the developed acidification-resistant organic fertilizer was used in sugarcane experiment.The results showed that in the treatment that the specific acidification-resistant organic fertilizer was applied,the yield of sugarcane significantly increased,the p H value of soil effectively increased,the physical and chemical properties of soil improved,and the contents of microorganisms and available nutrients in soil increased.展开更多
The branched-chain amino acids (BCAAs) valine, leucine and isoleucine are essential amino acids that are critical for animal growth and development. Animals need to obtain BCAAs from their diet because they cannot syn...The branched-chain amino acids (BCAAs) valine, leucine and isoleucine are essential amino acids that are critical for animal growth and development. Animals need to obtain BCAAs from their diet because they cannot synthesize them. Plants are the ultimate source of these amino acids. Acetolactate synthase (ALS) is the first common enzyme in the biosynthesis of BCAAs. The metabolic control of BCAA biosynthesis involves allosteric regulation of ALS by the end-products of the pathway, i.e., valine, leucine and isoleucine. ALS holoenzyme seems to consist of two large catalytic subunits and two small regulatory subunits. In a previous study, using homologous recombination dependent gene targeting we created rice plants in which W548Land S627I mutations were induced into the endogenous gene encoding the ALS catalytic subunit. These two amino acid substitutions conferred hypertolerance to the ALS-inhibiting herbicide bispyripac-sodium. In this study, we revealed that feedback regulation by valine and leucine was reduced by these two amino acid substitutions. Furthermore, in leaves and seeds of ALS mutants with W548Land/or S627I substitution, a 2- to 3-fold increase in BCAAs was detected. Our results suggest that the ALS catalytic subunit is also involved in feedback regulation of ALS, and that judicious modification of the regulatory and catalytic subunits of ALS-coding genes by gene targeting can lead to the efficient accumulation of BCAA in plants.展开更多
The aim of the paper was to study the metabolite profile and morphological characteristics of sugar beet regenerants exposed to aluminium ions (Al^3+). The regenerants were selected basing on selective media with s...The aim of the paper was to study the metabolite profile and morphological characteristics of sugar beet regenerants exposed to aluminium ions (Al^3+). The regenerants were selected basing on selective media with sublethal acidity (pH 3.5). The thrice-repeated passaging of sugar beet microclones of two genotypes in low pH medium causes certain alterations in the cellular metabolism. The paper demonstrated that peroxidase (POD) and isocitrate lyase (ICL) activity increased in both varieties. At the same time, NADH-dehydrogenase (NADH-DH) activity decreased in hybrid plants. Glucose-6-phosphate-dehydrogenase (gl-6-ph-dh) activity increased in mail sterile (MS) hybrid plants, but reduced in Ramonskaya fertile (RF) hybrid plants. Adaptation to reduced pH was accompanied by alterations in the isozyme spectra of POD, 1- and 2-esterase, cytochrome c oxidase and malic enzyme (ME). The adaptation process of sugar beet regenerants was also accompanied by an increase in protein synthesis. The level of metabolic response to stress very much depended on the initial genotype of the hybrid. In this experiment, aluminium resistant plants were growing rapidly in selective media. They developed leaves with healthy petioles and blades and had strong root systems.展开更多
[Objective]The aim was to clarify the chemical substance basis of hypoglycemic and lipid-lowering effects of Pu-erh Tea. [Method]Pu-erh Tea was extracted with 95% ethanol,followed by petroleum ether,chloroform,ethyl a...[Objective]The aim was to clarify the chemical substance basis of hypoglycemic and lipid-lowering effects of Pu-erh Tea. [Method]Pu-erh Tea was extracted with 95% ethanol,followed by petroleum ether,chloroform,ethyl acetate and n-butanol extraction,after the further purification and through the NKA-9 macroporous resin and many times of Sephadex column chromatography,two compounds were isolated,in the same time,the effect of Uracil and Gallic acid on α-amylase was studied. [Result]The Uracil and Gallic acid were isolated and identified respectively from Pu-erh Tea and the Uracil was firstly isolated from Pu-erh Tea; Gallic acid had strong inhibition on α-amylase. [Conclusion]It could provide some theories on the hypoglycemic and lipid-lowering effects of Pu-erh Tea.展开更多
The microstructure and corrosion resistance of different boric/sulfuric acid anodic(BSAA) films on 7050 aluminum alloy were studied by atomic force microscopy(AFM),electrochemical impedance spectroscopy(EIS) and...The microstructure and corrosion resistance of different boric/sulfuric acid anodic(BSAA) films on 7050 aluminum alloy were studied by atomic force microscopy(AFM),electrochemical impedance spectroscopy(EIS) and scanning Kelvin probe(SKP).The results show that boric acid does not change the structure of barrier layer of anodic film,but will significantly affect the structure of porous layer,consequently affect the corrosion resistance of anodic film.As the content of boric acid in electrolyte increases from 0 to 8 g/L,the resistance of porous layer(Rp) of BSAA film increases,the capacitance of porous layer(CPEp) decreases,the surface potential moves positively,the pore size lessens,and the corrosion resistance improves.However,the Rp,CPEp and surface potential will change towards opposite direction when the content of boric acid is over 8 g/L.展开更多
This paper focused on the effect of spraying chitosan and salicylic acid to Litchi under low temperature stress conditions.The physiology and biochemistry of litchi were studied as well.Results showed that the appropr...This paper focused on the effect of spraying chitosan and salicylic acid to Litchi under low temperature stress conditions.The physiology and biochemistry of litchi were studied as well.Results showed that the appropriate concentration of chitosan and salicylic acid treatment could effectively reduce injury caused by low temperature to litchi,compared with water control,chlorophyll,proline,soluble protein content of litchi after treatment and the activity of protective enzyme increasing significantly.However,the accumulation of resistance could significantly be improved.Furthermore,when 1 000 mg/L chitosan combined with 50 mg/L salicylic acid,the litchi acquired the best cold resistance capability.展开更多
[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly sus...[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly susceptible to disease as experimental material, the changes of catalase(CAT), and superoxide dismutase(SOD) and MDA activities in rice treated by BABA were investigated. [Result] In rice plants treated by BABA, the activities of CAT and SOD increased, meanwhile the MDA content also rose to some extent, resulting in the disease resistance to rice blast. [Conclusion] By influencing reactive oxygen metabolism, BABA endows rice plants with resistance to rice blast. BABA is safe to environment and has highly resistance-inducing capacity, it could be generalized in production.展开更多
基金supported by the Fund of State Key Laboratory of Deep Oil and Gas,China University of Petroleum (East China) (SKLDOG2024-ZYRC-06)Key Program of National Natural Science Foundation of China (52130401)+2 种基金National Natural Science Foundation of China (52104055,52250410349)Major Science and Technology Project of China National Petroleum Corporation Limited (2021ZZ01-08)Shandong Provincial Natural Science Foundation,China (ZR2021ME171)。
文摘CO_(2) flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can also cause severe CO_(2) gas channeling problems.Therefore,anti-gas channeling is a necessary measure to improve the effect of CO_(2) flooding.The kind of anti-gas channeling refers to the plugging of fractures in the deep formation to prevent CO_(2) gas channeling,which is different from the wellbore leakage.Polymer microspheres have the characteristics of controllable deep plugging,which can achieve the profile control of low-permeability fractured reservoirs.In acidic environments with supercritical CO_(2),traditional polymer microspheres have poor expandability and plugging properties.Based on previous work,a systematic evaluation of the expansion performance,dispersion rheological properties,stability,deep migration,anti-CO_(2) channeling and enhanced oil recovery ability of a novel acid-resistant polymer microsphere(DCNPM-A)was carried out under CQ oilifield conditions(salinity of85,000 mg/L,80℃,pH=3).The results show that the DCNPM-A microsphere had a better expansion performance than the traditional microsphere,with a swelling rate of 13.5.The microsphere dispersion with a concentration of 0.1%-0.5%had the advantages of low viscosity,high dispersion and good injectability in the low permeability fractured core.In the acidic environment of supercritical CO_(2),DCNPM-A microspheres showed excellent stability and could maintain strength for over 60 d with less loss.In core experiments,DCNPM-A microspheres exhibited delayed swelling characteristics and could effectively plug deep formations.With a plugging rate of 95%,the subsequent enhanced oil recovery of CO_(2) flooding could reach 21.03%.The experimental results can provide a theoretical basis for anti-CO_(2)channeling and enhanced oil recovery in low-permeability fractured reservoirs.
基金by National Natural Science Foundation of China(81803224)Young Scholars Program of Shandong University(2018WLJH33)to X.G.+3 种基金National Natural Science Foundation of China(81973031)Cheeloo Young Scholar Program of Shandong University(21320089963054)to H.W.Young Scholars Program of Shandong University(2018WLJH34)the Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology(LMDBKF-2019-05)to L.D.
文摘With the prevalence of obesity and obesity-related metabolic syndrome,such as insulin resistance in recent years,it is urgent to explore effective interventions to prevent the progression of obesity-related metabolic syndrome.Palmitoleic acid is a monounsaturated fatty acid that is available from dietary sources,mainly derived from marine products.P almitoleic acid plays a positive role in maintaining glucose homeostasis and reducing inflammation.However,it is still unknow the mechanism of palmitoleic acid in ameliorating insulin resistance.Here,we investigated the effects of palmitoleic acid on chow diet(CD)-fed and high-fat diet(HFD)-fed mice,which were fed CD or HFD for 12 weeks before administration.We administrated mice with BSA(control),oleic acid,or palmitoleic acid for 6 weeks on top of CD or HFD feeding.We found that palmitoleic acid only improved glucose homeostasis in HFD-fed obese mice by increasing glucose clearance and reducing HOMA-IR.Further study explored that palmitoleic acid changed the composition of gut microbiota by decreasing Firmicutes population and increasing Bacteroidetes population.In colon,palmitoleic acid increased intestinal tight junction integrity and reduced inflammation.Moreover,palmitoleic acid decreased macrophage infiltration in liver and adipose tissue and increase glucose uptake in adipose tissue.Diacylglycerol(DAG)in tissue(for example,liver)is found to positively correlated with HOMA-IR.HFD enhanced the levels of DAGs in liver but not in adipose tissue in this study.Palmitoleic acid did not reverse the high DAG levels induced by HFD in liver.Therefore,in HFD-fed mice,palmitoleic acid reduced insulin resistance by an independent-manner of DAGs.It might be associated with the beneficial effects of palmitoleic acid on altering the gut microbiota composition,improving of intestinal barrier function,and downregulating the inflammation in colon,liver,and adipose tissue.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51601108 and 52071191)the Natural Science Foundation of Shandong Province(ZR2020ME011).
文摘In this study,the effects of intermetallic compounds(Mg_(17)Al_(12)and Al_(8)Mn_(5))on the Mg-Al layered double hydroxide(LDH)formation mechanism and corrosion behavior of an in-situ LDH/Mg(OH)_(2)steam coatings on AZ80 Mg alloy were investigated.Citric acid(CA)was used to activate the alloy surface during the pretreatment process.The alloy was first pretreated with CA and then subjected to a hydrothermal process using ultrapure water to produce Mg-Al-LDH/Mg(OH)_(2)steam coating.The effect of different time of acid pretreatment on the activation of the intermetallic compounds was investigated.The microstructure and elemental composition of the obtained coatings were analyzed using FE-SEM,EDS,XRD and FT-IR.The corrosion resistance of the coated samples was evaluated using different techniques,i.e.,potentiodynamic polarization(PDP),electrochemical impedance spectrum(EIS)and hydrogen evolution test.The results indicated that the CA pretreatment significantly influenced the activity of the alloy surface by exposing the intermetallic compounds.The surface area fraction of Mg_(17)Al_(12)and Al_(8)Mn_(5)phases on the surface of the alloy was significantly higher after the CA pretreatment,and thus promoted the growth of the subsequent Mg-Al-LDH coatings.The CA pretreatment for 30 s resulted in a denser and thicker LDH coating.Increase in the CA pretreatment time significantly led to the improvement in corrosion resistance of the coated AZ80 alloy.The corrosion current density of the coated alloy was lower by three orders of magnitude as compared to the uncoated alloy.
基金supported by the China Agriculture Research System of MOF and MARA(CARS-12)the Open Fund of the National Key Laboratory of Crop Genetic Improvement(ZK201909)。
文摘Clubroot and herbicide resistance,high oleic acid(OA)content,and early maturity are targets of rapeseed(Brassica napus L.)breeding.The objective of this study was to develop new male-fertility restorer lines by pyramiding favorable genes to improve these traits simultaneously.Seven elite alleles for the four traits were introduced into the restorer line 621R by speed breeding with marker-assisted and phenotypic selection.Six introgression lines(ILs)were developed with four-to seven-gene combinations and crossed with two elite parents to develop hybrids.All ILs and their corresponding hybrids displayed high resistance to both clubroot pathotype 4 and sulfonylurea herbicides.Three ILs and their hybrids showed large increases in OA contents and four showed earlier maturity.These new ILs may be useful in rapeseed hybrid breeding for the target traits.
基金This work was supported by National Science and Technology Major Project(2012ZX09304004)National Basic Research Program of China(973 Program,2010CB934000)+1 种基金National Natural Science Foundation of China(81072593,81102402)Specialized Research Fund for the Doctoral Program of Higher Education(20110071130011).
文摘We encapsulated vincristine into folic acid-conjugated PEGylated liposomes to improve the anti-tumor efficacy on multidrug resistant cancers.It was observed that the drug delivery system we constructed exhibited maximum cytotoxicity on KBv200 cells(multidrug resistant variant)compared with any other formulations.The semi-quantitative analysis of region of interest revealed that there was a great increase in area under curve(AUC)of a near-infrared fluorescein in solid tumors due to folic acid-mediated accumulation.Folic acid-conjugated PEGylated liposomes showed a significant tumor growth inhibiting effect in vitro and in vivo.TUNEL assay revealed that folic acid-conjugated PEGylated liposomes could induce cell apoptosis much more greatly than others.This study demonstrated that it had potential application prospective for the treatment of multidrug resistant cancer.
基金supported by the Faculty of Medicine Research Fund(GEN2-01/2016),Thammasat University,Thailand
文摘Objective: To evaluate the insulin sensitivity action of ferulic acid(FA) in skeletal muscle and hypothalamus of high-fat diet(HFD)-induced obese mice. Methods: Obese mouse model was induced by HFD(45 kcal% lard fat) for 16 weeks. After 8 weeks of HFD feeding, these obese mice were orally treated with FA at doses of 25 and 50 mg/kg/day for 8 weeks. At the end of all treatments, the epididymal fat, pancreas, skeletal muscle and hypothalamus were removed for biochemical parameter and protein expression examinations. Results: FA treatment significantly decreased leptin level in fat tissue and insulin level in pancreas(P < 0.05). Interestingly, obese mice treated with FA increased the protein expressions of insulin receptor substrate-1, phosphatidylinositol 3-kinase, and phosphorylated-protein kinase B in both muscle and brain(P < 0.05). The phosphorylations of adenosine monophosphate-activated protein kinase and acetyl-CoA carboxylase in muscle, and leptin receptor protein in hypothalamus were also increased(P < 0.05). The pancreatic islets histology showed smaller size in obese mice treated with FA compared to untreated obese mice. Conclusions: These findings indicate the beneficial effect of FA in improving insulin resistance in HFD-induced obese mice. These effects are probably mediated via modulating the insulin receptor substrate/phosphatidylinositol 3-kinase/protein kinase B or adenosine monophosphate-activated protein kinase pathways.
基金supported by Suzhou Science and Technology Development Plan (SKJYD2021047)the Fundation of Suzhou Kowloon Hospital (SZJL202111 and SZJL202104)
文摘Objective:To explore the mechanism of drug resistance in acute lymphoblastic leukemia and the anti-tumor effect of combination therapy of dehydroabietic acid and vincristine against acute lymphoblastic leukemia cells.Methods:Acute lymphoblastic leukemia cells REH and CCRFCEM were employed to detect the anti-tumor effect of vincristine and doxorubicin on proliferation and apoptosis using EdU assay,human active caspase-3 Quantikine ELISA kit,and flow cytometry.Vincristine-resistant REH cells(REH-R),survivin knockdown and overexpressing REH cells were established to verify the role of survivin in drug resistance.Additionally,in vitro and in vivo assays were performed to determine the effect of dehydroabietic acid on the cytotoxicity of vincristine.Results:Vincristine and doxorubicin markedly suppressed proliferation and induced apoptosis of REH and CCRF-CEM cells.Survivin expression was upregulated in REH-R cells compared with REH cells.Knockdown of survivin expression obviously restored the sensitivity of REH-R cells to vincristine.Akt phosphorylation was also increased in REH-R cells compared to REH cells.In addition,LY294002,a PI3k/Akt pathway blocker,inhibited survivin expression and enhanced cytotoxicity of vincristine to REH-R cells.Dehydroabietic acid effectively reduced survivin expression in REH-R cells,thereby enhancing the therapeutic effect of vincristine on drug-resistant cells.Survivin overexpression markedly reduced the effect of dehydroabietic acid on enhancing the anti-proliferation and inducing apoptosis effect of vincristine.Moreover,the combination of dehydroabietic acid with vincristine significantly extended the survival rate in a mouse xenograft model of acute lymphoblastic leukemia,compared with vincristine treatment alone.Conclusions:Dehydroabietic acid may be used as a potential candidate for the treatment of acute lymphoblastic leukemia in combination with vincristine.
文摘<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococcus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> is reported severally to be resistant to the drugs often used empirically for treatment of urinary tract infections (UTIs). Their ability to exhibit resistance to multiple drugs is a great de</span><span style="font-family:Verdana;">al of threat to successes recorded in the management of UTIs cause</span><span style="font-family:Verdana;">d by this pathogen. Lactic acid bacteria (LAB) have been demonstrated to exhibit an</span><span style="font-family:Verdana;">timicrobial activities but studies about their prospect against multi</span><span style="font-family:Verdana;">-drug resistant </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> are quite few. This study therefore investigated acti</span><span><span style="font-family:Verdana;">vities of LAB against the multi-drug resistant </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> recover</span></span><span style="font-family:Verdana;">ed fro</span><span style="font-family:Verdana;">m urine samples of symptomatic women. The three differ</span><span style="font-family:Verdana;">ent species of LAB </span><span><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 62, </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 86 and </span><i><span style="font-family:Verdana;">Weis</span></i></span><i><span style="font-family:Verdana;">sella</span></i><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> BTA 40) previously isolated and identified by 16S rRNA s</span><span style="font-family:;" "=""><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;">quencing were selected based on their history of antimicrobial activities. Their</span><span style="font-family:Verdana;"> m</span><span style="font-family:Verdana;">etabolites were employed in the antagonistic assays against six (6) mu</span><span style="font-family:Verdana;">lti-drug resista</span><span style="font-family:Verdana;">nt test pathogens recovered fro</span><span style="font-family:Verdana;">m urine samples of symptomatic, non-pregnant women attending clinics in Lagos, Nigeria and the control (</span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> subs bovis strain DSM 18669) following standard procedures. </span><span style="font-family:Verdana;">The pathogens showed resistances to almost all the antibiotics except</span><span style="font-family:Verdana;"> levofloxaci</span><span style="font-family:Verdana;">n, ciprofloxacin, imipenem while the control showed resistance to thr</span><span style="font-family:Verdana;">ee. The LAB, </span><i><span style="font-family:Verdana;">L.</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> inhibited five (83.3%) of the pathogens with zone diameter of 12 - 17 mm, followed by </span><i><span style="font-family:Verdana;">W</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> inhibiting three (50%) with 15 - 17 mm. </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> on the other hand, inhibited a pathogen and the control with zones of 13 mm and 14 mm respectively. In conclusion, the extracted metabolites of LAB inhibited the growth of multi-drug resistant clinical isolates of uropathogenic </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> and may therefore be potent alternatives to antibiotics.</span></span>
基金This work was supported by the National Key R&D Program of China(Nos.2022YFB3504100 and 2022YFB3504102)Natural National Science Foundation of China(No.22276133)+1 种基金Natural National Science Foundation of China(No.U20A20132)Natural National Science Foundation of China(No.52106180).
文摘The existence of alkali metals in fl ue gases originating from stationary sources can result in catalyst deactivation in the low-temperature selective catalytic reduction(SCR)of nitrogen oxides(NO_(x)).It is widely accepted that alkali metal poisoning causes damage to the acidic sites of catalysts.Therefore,in this study,a series of CoMn catalysts doped with heteropolyacids(HPAs)were prepared using the coprecipitation method.Among these,CoMnHPMo exhibited superior catalytic performance for SCR and over 95%NO_(x) conversion at 150-300.Moreover,it exhibited excellent catalytic activity and stability after alkali poisoning,demonstrating outstanding alkali metal resistance.The characterization indicated that HPMo increased the specifi c surface area of the catalyst,which provided abundant adsorption sites for NO_(x) and NH_(3).Comparing catalysts before and after poisoning,CoMnHPMo enhanced its alkali metal resistance by sacrifi cing Brønsted acid sites to protect its Lewis acid sites.In situ DRIFTS was used to study the reaction pathways of the catalysts.The results showed that CoMnHPMo maintained high NH_(3) adsorption capacity after K poisoning and then reacted rapidly with NO intermediates to ensure that the active sites were not covered.Consequently,SCR performance was ensured even after alkali metal poisoning.In sum-mary,this research proposed a simple method for the design of an alkali-resistant NH_(3)-SCR catalyst with high activity at low temperatures.
基金financially supported by the National Natural Science Foundation of China [81273409]the Program for Changjiang Scholars and Innovative Research Team in University [IRT_15R37]the Ministry of Science and Technology of China [2017YFA0205301]
文摘Objective To evaluate the synergy of the Burkholderia signaling molecule cis-2-dodecenoic acid(BDSF) and fluconazole(FLU) or itraconazole(ITRA) against two azole-resistant C. albicans clinical isolates in vitro and in vivo. Methods Minimum inhibitory concentrations(MICs) of antibiotics against two azole-resistant C. albicans were measured by the checkerboard technique, E-test, and time-kill assay. In vivo antifungal synergy testing was performed on mice. Analysis of the relative gene expression levels of the strains was conducted by quantitative reverse-transcription polymerase chain reaction(qR T-PCR). Results BDSF showed highly synergistic effects in combination with FLU or ITRA with a fractional inhibitory concentration index of ≤ 0.08. BDSF was not cytotoxic to normal human foreskin fibroblast cells at concentrations of up to 300 μg/mL. The qR T-PCR results showed that the combination of BDSF and FLU/ITRA significantly inhibits the expression of the efflux pump genes CDR1 and MDR1 via suppression of the transcription factors TAC1 and MRR1, respectively, when compared with FLU or ITRA alone. No dramatic difference in the mR NA expression levels of ERG1, ERG11, and UPC2 was found, which indicates that the drug combinations do not significantly interfere with UPC2-mediated ergosterol levels. In vivo experiments revealed that combination therapy can be an effective therapeutic approach to treat candidiasis. Conclusion The synergistic effects of BDSF and azoles may be useful as an alternative approach to control azole-resistant Candida infections.
基金supported by the Key R&D Program of Lishui City(2021ZDYF12,2022ZDYF07,2023zdyf14)Natural Science Foundation of China(82072026,82072025 and 82272090)+1 种基金Zhejiang Provincial Natural Science Foundation(LY23H180003,LQ22H180010)Provincial and Ministerial Joint Construction of Key Projects(WKJ-ZJ-2317).
文摘Chemotherapy plays a crucial role in triple-negative breast cancer (TNBC) treatment as it not only directly kills cancer cells but also induces immunogenic cell death. However, the chemotherapeutic efficacy was strongly restricted by the acidic and hypoxic tumor environment. Herein, we have successfully formulated PLGA-based nanoparticles concurrently loaded with doxorubicin (DOX), hemoglobin (Hb) and CaCO3 by a CaCO3-assisted emulsion method, aiming at the effective treatment of TNBC. We found that the obtained nanomedicine (DHCaNPs) exhibited effective drug encapsulation and pH-responsive drug release behavior. Moreover, DHCaNPs demonstrated robust capabilities in neutralizing protons and oxygen transport. Consequently, DHCaNPs could not only serve as oxygen nanoshuttles to attenuate tumor hypoxia but also neutralize the acidic tumor microenvironment (TME) by depleting lactic acid, thereby effectively overcoming the resistance to chemotherapy. Furthermore, DHCaNPs demonstrated a notable ability to enhance antitumor immune responses by increasing the frequency of tumor-infiltrating effector lymphocytes and reducing the frequency of various immune-suppressive cells, therefore exhibiting a superior efficacy in suppressing tumor growth and metastasis when combined with anti-PD-L1 (αPD-L1) immunotherapy. In summary, this study highlights that DHCaNPs could effectively attenuate the acidic and hypoxic TME, offering a promising strategy to figure out an enhanced chemo-immunotherapy to benefit TNBC patients.
基金Supported by the National Natural Science Foundation of China(Nos.50803055, 30872902).
文摘Block copolymer polystyrene-b-poly(acrylic acid)(PS-b-PAA) was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtained. Acid resistant properties of this type of hybrid CaCO3 were studied. Size measurement shows that the acid resistant properties of the hybrid particles are different in different solutions, such as HCl, EDTA, and H2SO4 solutions.
基金Supported by the Preresearch Project of the National Natural Science Foundation of China,No.ZRYY1906the Applied Basic Research Project of the Science and Technology Department of Sichuan Province,No.2021YJ0154+1 种基金the Talent Research Promotion Plan of Xinglin Scholars of Chengdu University of Traditional Chinese Medicine,No.QNXZ2019035the Chengdu University of Traditional Chinese Medicine‘Xinglin Scholars'subject talent research promotion Program(young scholars),No.QNXZ2019037.
文摘BACKGROUND Lingguizhugan(LGZG)decoction is a widely used classic Chinese medicine formula that was recently shown to improve high-fat diet(HFD)-induced insulin resistance(IR)in animal studies.AIM To assess the therapeutic effect of LGZG decoction on HFD-induced IR and explore the potential underlying mechanism.METHODS To establish an IR rat model,a 12-wk HFD was administered,followed by a 4-wk treatment with LGZG.The determination of IR status was achieved through the use of biochemical tests and oral glucose tolerance tests.Using a targeted metabolomics platform to analyze changes in serum metabolites,quantitative real-time PCR(qRT-PCR)was used to assess the gene expression of the ribosomal protein S6 kinase beta 1(S6K1).RESULTS In IR rats,LGZG decreased body weight and indices of hepatic steatosis.It effectively controlled blood glucose and food intake while protecting islet cells.Metabolite analysis revealed significant differences between the HFD and HFDLGZG groups.LGZG intervention reduced branched-chain amino acid levels.Levels of IR-related metabolites such as tryptophan,alanine,taurine,and asparagine decreased significantly.IR may be linked to amino acids due to the contemporaneous increase in S6K1 expression,as shown by qRT-PCR.CONCLUSIONS Our study strongly suggests that LGZG decoction reduces HFD-induced IR.LGZG may activate S6K1 via metabolic pathways.These findings lay the groundwork for the potential of LGZG as an IR treatment.
基金Supported by Science and Technology Planning Project of Guangxi,China(Guike AD19245169,Guike AD18281072,Guike AA17202037,Guike AB16380164).
文摘The soil in Guangxi has been severely acidified,restricting sustainable development of agriculture.In this paper,based on the screening of organic fertilizer additives,a method for the production of acidification-resistant organic fertilizer specific for acid red soil improvement was proposed,and the developed acidification-resistant organic fertilizer was used in sugarcane experiment.The results showed that in the treatment that the specific acidification-resistant organic fertilizer was applied,the yield of sugarcane significantly increased,the p H value of soil effectively increased,the physical and chemical properties of soil improved,and the contents of microorganisms and available nutrients in soil increased.
文摘The branched-chain amino acids (BCAAs) valine, leucine and isoleucine are essential amino acids that are critical for animal growth and development. Animals need to obtain BCAAs from their diet because they cannot synthesize them. Plants are the ultimate source of these amino acids. Acetolactate synthase (ALS) is the first common enzyme in the biosynthesis of BCAAs. The metabolic control of BCAA biosynthesis involves allosteric regulation of ALS by the end-products of the pathway, i.e., valine, leucine and isoleucine. ALS holoenzyme seems to consist of two large catalytic subunits and two small regulatory subunits. In a previous study, using homologous recombination dependent gene targeting we created rice plants in which W548Land S627I mutations were induced into the endogenous gene encoding the ALS catalytic subunit. These two amino acid substitutions conferred hypertolerance to the ALS-inhibiting herbicide bispyripac-sodium. In this study, we revealed that feedback regulation by valine and leucine was reduced by these two amino acid substitutions. Furthermore, in leaves and seeds of ALS mutants with W548Land/or S627I substitution, a 2- to 3-fold increase in BCAAs was detected. Our results suggest that the ALS catalytic subunit is also involved in feedback regulation of ALS, and that judicious modification of the regulatory and catalytic subunits of ALS-coding genes by gene targeting can lead to the efficient accumulation of BCAA in plants.
文摘The aim of the paper was to study the metabolite profile and morphological characteristics of sugar beet regenerants exposed to aluminium ions (Al^3+). The regenerants were selected basing on selective media with sublethal acidity (pH 3.5). The thrice-repeated passaging of sugar beet microclones of two genotypes in low pH medium causes certain alterations in the cellular metabolism. The paper demonstrated that peroxidase (POD) and isocitrate lyase (ICL) activity increased in both varieties. At the same time, NADH-dehydrogenase (NADH-DH) activity decreased in hybrid plants. Glucose-6-phosphate-dehydrogenase (gl-6-ph-dh) activity increased in mail sterile (MS) hybrid plants, but reduced in Ramonskaya fertile (RF) hybrid plants. Adaptation to reduced pH was accompanied by alterations in the isozyme spectra of POD, 1- and 2-esterase, cytochrome c oxidase and malic enzyme (ME). The adaptation process of sugar beet regenerants was also accompanied by an increase in protein synthesis. The level of metabolic response to stress very much depended on the initial genotype of the hybrid. In this experiment, aluminium resistant plants were growing rapidly in selective media. They developed leaves with healthy petioles and blades and had strong root systems.
基金Supported by National Science and Technology Support Project(2007BAD58B04 )Special Fund Project of Modern Agriculture(Tea) Industrial Technology SystemYunnan Department of Education and Scientific Research Fund (07Y40163)~~
文摘[Objective]The aim was to clarify the chemical substance basis of hypoglycemic and lipid-lowering effects of Pu-erh Tea. [Method]Pu-erh Tea was extracted with 95% ethanol,followed by petroleum ether,chloroform,ethyl acetate and n-butanol extraction,after the further purification and through the NKA-9 macroporous resin and many times of Sephadex column chromatography,two compounds were isolated,in the same time,the effect of Uracil and Gallic acid on α-amylase was studied. [Result]The Uracil and Gallic acid were isolated and identified respectively from Pu-erh Tea and the Uracil was firstly isolated from Pu-erh Tea; Gallic acid had strong inhibition on α-amylase. [Conclusion]It could provide some theories on the hypoglycemic and lipid-lowering effects of Pu-erh Tea.
文摘The microstructure and corrosion resistance of different boric/sulfuric acid anodic(BSAA) films on 7050 aluminum alloy were studied by atomic force microscopy(AFM),electrochemical impedance spectroscopy(EIS) and scanning Kelvin probe(SKP).The results show that boric acid does not change the structure of barrier layer of anodic film,but will significantly affect the structure of porous layer,consequently affect the corrosion resistance of anodic film.As the content of boric acid in electrolyte increases from 0 to 8 g/L,the resistance of porous layer(Rp) of BSAA film increases,the capacitance of porous layer(CPEp) decreases,the surface potential moves positively,the pore size lessens,and the corrosion resistance improves.However,the Rp,CPEp and surface potential will change towards opposite direction when the content of boric acid is over 8 g/L.
文摘This paper focused on the effect of spraying chitosan and salicylic acid to Litchi under low temperature stress conditions.The physiology and biochemistry of litchi were studied as well.Results showed that the appropriate concentration of chitosan and salicylic acid treatment could effectively reduce injury caused by low temperature to litchi,compared with water control,chlorophyll,proline,soluble protein content of litchi after treatment and the activity of protective enzyme increasing significantly.However,the accumulation of resistance could significantly be improved.Furthermore,when 1 000 mg/L chitosan combined with 50 mg/L salicylic acid,the litchi acquired the best cold resistance capability.
基金Supported by National Key Technology R&D Program During the Eleventh Five Year Plan (2006BAD08A04)Innovation Project(20076020)~~
文摘[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly susceptible to disease as experimental material, the changes of catalase(CAT), and superoxide dismutase(SOD) and MDA activities in rice treated by BABA were investigated. [Result] In rice plants treated by BABA, the activities of CAT and SOD increased, meanwhile the MDA content also rose to some extent, resulting in the disease resistance to rice blast. [Conclusion] By influencing reactive oxygen metabolism, BABA endows rice plants with resistance to rice blast. BABA is safe to environment and has highly resistance-inducing capacity, it could be generalized in production.