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1.
Sci Total Environ ; : 173473, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38788936

ABSTRACT

Cadmium (Cd) contamination in cropland poses a significant threat to the quality of agricultural products, but even though in-situ remediation has been extensively applied, non-selective immobilization remains an issue. In order to develop a material that specifically immobilizes Cd in soil, a layered double hydroxide, intercalated with mercaptosuccinic acid (MSA-CFA), was synthesized through co-precipitation. In this case, the MSA-CFA's maximum adsorption capacity was increased from the 513.8 mg·g-1 for unintercalated hydrotalcite CFA to 692.6 mg·g-1. Besides, MSA-CFA efficiently removed 99.25 % of Cd from soil water-extract solution and immobilized up to 70.03 % of bio-available Cd. However, interestingly, its immobilization effects on beneficial metal elements Fe, Mn and Zn were milder, being equivalent to 2/7, 5/7 and 1/2 that of lime, respectively. Moreover, XRD and XPS techniques revealed isomorphous substitution with calcium and sulfhydryl complexation during the Cd adsorption by MSA-CFA. Compared with CFA, the increased adsorption capacity of MSA-CFA for Cd was due to intercalated MSA acting as a new adsorption site, while the enhanced selectivity was contributed by sulfhydryl's affinity for Cd. Altogether, MSA-CFA showed great promise as a competitive and highly efficient candidate amendment in Cd-contaminated soil remediation.

2.
J Hazard Mater ; 465: 133408, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38183938

ABSTRACT

The biogeochemical cycling of iron (Fe) or sulfur (S) in paddy soil influences the cadmium (Cd) and arsenic (As) migration. However, the influence of coupled reduction effects and reaction precedence of Fe and S on the bioavailability of Cd and As is still not fully understood. This study aimed to reveal the influence of Fe and S reduction on soil Cd and As mobility under various pe + pH conditions and to elucidate the related mechanism in subtropical China. According to the findings, higher adsorption from Fe reduction caused high-crystalline goethite (pe + pH > 2.80) to become amorphous ferrihydrite, which in turn caused water-soluble Cd (62.0%) to first decrease. Cd was further decreased by 72.7% as a result of the transformation of SO42- to HS-/S2- via sulfate reduction and the formation of CdS and FeS. As release (an increase of 8.1 times) was consequently caused by the initial reduction and dissolution of iron oxide (pe + pH > 2.80). FeS had a lesser impact on the immobilization of As than sulfate-mediated As (V) reduction in the latter stages of the reduction process (pe + pH < 2.80). pe + pH values between 3 and 3.5 should be maintained to minimize the bioavailability of As and Cd in moderate to mildly polluted soil without adding iron oxides and sulfate amendments. The practical remediation of severely co-contaminated paddy soil can be effectively achieved by using Fe and S additions at different pe + pH conditions. This technique shows promise in reducing the bioavailability of Cd and As.

3.
Chem Biol Drug Des ; 103(1): e14389, 2024 01.
Article in English | MEDLINE | ID: mdl-37955286

ABSTRACT

Twenty-one new coumarin Mannich base derivatives (11a-u) were synthesized, which exhibited antiproliferation activities in HepG2 (liver cancer), A549 (lung cancer), MCF-7 (breast cancer), and HT-29 (colon cancer). Most of the target compounds showed the most potent activity against HepG2 cells compared with other cancer cells, compound 11g showed the strongest antiproliferative activity (2.10 µM) against HepG2, even superior to the positive control drug 5-FU(5.49 µM). The nitric oxide (NO) release of all compounds in HepG2 cells was determined, of which compound 11g showed high levels of NO release (10.8 µM). Notably, the solubility of compound 11g increased 13-fold compared with the lead 8. The preliminary cytotoxicity studies suggest that 11g had little effect on LO2 cells(normal liver cells, >50 µM). The effect of compound 11g on the apoptosis of HepG2 cells was also studied, and the results showed that the induction effect of compound 11g on apoptosis is a concentration-dependent manner. Our results indicate that compound 11g might be a promising lead for further studies.


Subject(s)
Antineoplastic Agents , Mannich Bases , Humans , Molecular Structure , Structure-Activity Relationship , Mannich Bases/pharmacology , Coumarins/pharmacology , Antineoplastic Agents/pharmacology , Cell Proliferation , Drug Screening Assays, Antitumor , Nitric Oxide , Cell Line, Tumor , Apoptosis
4.
Molecules ; 28(12)2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37375431

ABSTRACT

Developing a new generation of anticancer metal-based drugs that can both kill tumor cells and inhibit cell migration is a promising strategy. Herein, we synthesized three Cu(II), Zn(II), and Mn(II) complexes derived from 5-chloro-2-N-(2-quinolylmethylene)aminophenol (C1-C3). Among these complexes, the Cu(II) complex (C1) showed significantly greater cytotoxicity toward lung cancer cell lines than cisplatin. C1 inhibited A549 cell metastasis and suppressed the growth of the A549 tumor in vivo. In addition, we confirmed the anticancer mechanism of C1 by triggering multiple mechanisms, including inducing mitochondrial apoptosis, acting on DNA, blocking cell cycle arrest, inducing cell senescence, and inducing DNA damage.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Cell Line, Tumor , Aminophenols/pharmacology , Antineoplastic Agents/pharmacology , Cisplatin/pharmacology , Apoptosis , Zinc/pharmacology , Coordination Complexes/pharmacology , Copper/pharmacology , Cell Proliferation
5.
Neuropsychologia ; 181: 108489, 2023 03 12.
Article in English | MEDLINE | ID: mdl-36669696

ABSTRACT

One critical approach for promoting the efficiency of memory is to adopt selective encoding strategies to prioritize more valuable information. Past neuroimaging studies have shown that value-directed modulation of verbal memory depends heavily on the engagement of left-lateralized semantic processing regions, particularly in the ventrolateral prefrontal cortex (VLPFC). In the present study, we used high-definition transcranial direct current stimulation (HD-tDCS) to seek evidence for a causal role of left VLPFC in supporting the memory advantage for high-value items. Three groups of healthy young adult participants were presented with lists of words to remember, with each word accompanied by an arbitrarily assigned point value. During the first session, all participants received sham stimulation as they encoded five lists of 30 words each. Two of these lists were immediately tested with free recall, with feedback given to allow participants to develop metacognitive insight and strategies to maximize their point total. The second session had the exact same structure as the first, but the groups differed in whether they received continued sham stimulation (N = 22) or anodal stimulation of the left VLPFC (N = 21) or right VLPFC (N = 20). Those lists not tested with immediate recall were tested with recognition judgments after a one-day delay. Since no brain stimulation was applied during this Day 2 test, any performance differences can be attributed to the effects of stimulation on Day 1 encoding processes. Anodal stimulation of left VLPFC significantly boosted participants' memory encoding selectivity. In comparison, no such effect was seen in participants who received right VLPFC or sham stimulation. Estimates of recollection- and familiarity-based responding revealed that left VLPFC stimulation specifically amplified the effects of item value on recollection. These results demonstrate a causal role for left VLPFC in the implementation of selective value-directed encoding strategies, putatively by boosting deep semantic processing of high-value words. Our findings also provide further evidence on the hemispheric lateralization of value-directed verbal memory encoding.


Subject(s)
Transcranial Direct Current Stimulation , Young Adult , Humans , Transcranial Direct Current Stimulation/methods , Prefrontal Cortex/diagnostic imaging , Prefrontal Cortex/physiology , Mental Recall/physiology , Recognition, Psychology/physiology , Memory, Short-Term
6.
Pharm Biol ; 60(1): 1047-1054, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35649705

ABSTRACT

CONTEXT: Ellagic acid (EA) is a phenolic constituent in certain fruits and has largely been recognized for its role as an antioxidant compound. OBJECTIVE: To evaluate the effect of EA on beryllium sulphate-induced splenic toxicity in rats. MATERIALS AND METHODS: Male Sprague-Dawley rats were divided into four groups. The first group was used as control. Group 2 was exposed to BeSO4 (12 mg/kg, b.w.). Groups 3 and 4 were treated with EA (100 and 300 mg/kg, b.w.) daily for 6 weeks after exposing to BeSO4 (12 mg/kg, b.w.). Various biochemical and molecular biomarkers were assessed in blood and spleen. RESULTS: BeSO4-intoxicated rats showed significant higher WBC (6.74 ± 0.20 × 109/L vs. 11.02 ± 1.31 × 109/L, p < 0.05), Neu (1.14 ± 0.11 × 109/L vs. 2.45 ± 0.42 × 109/L, p < 0.05), Lym (3.80 ± 0.83 × 109/L vs. 9.64 ± 1.99 × 109/L, p < 0.05), and PLT (868.4 ± 43.2 × 109/L vs. 1408 ± 77.57 × 109/L, p < 0.05) than normal control animals. Moreover, an increase in MDA with depletion of GSH and SOD activity (all p < 0.05) occurred in the spleen of rats treated with BeSO4. Furthermore, BeSO4-treated rats displayed significantly higher levels of apoptotic markers (Bax, Caspase-3, PARP) (all p < 0.05). EA administration resulted in a significant reversal of hematological and apoptotic markers in beryllium sulphate-intoxicated rats. DISCUSSION AND CONCLUSIONS: Our results suggest EA treatment exerts a significant protective effect on BeSO4-induced splenic toxicity in rats.


Subject(s)
Ellagic Acid , Spleen , Animals , Beryllium , Ellagic Acid/pharmacology , Male , Oxidative Stress , Rats , Rats, Sprague-Dawley
7.
Biosci. j. (Online) ; 36(6): 2020-2028, 01-11-2020. ilus, tab, graf
Article in English | LILACS | ID: biblio-1148292

ABSTRACT

Pseudomonas syringae pv. actinidiae is a bacterial pathogen of kiwifruit. Based on the results of the pathogenicity assay, we sequenced the strain Pseudomonas syringae (Psa3) P155 which possesses a series of virulence and resistance genes, CRISPR candidate elements, prophage related sequences, methylation modifications, genomic islands as well as one plasmid. Most importantly, the copper resistance genes copA, copB, copC, copD, and copZ as well as aminoglycoside resistance gene ksgA were identified in strain P155, which would pose a threat to kiwifruit production. The complete sequence we reported here will provide valuable information for a better understanding of the genetic structure and pathogenic characteristics of the genome of P155.


Pseudomonas syringae pv. actinidiae agente causal do cancro bacteriano do kiwi. Com base nos resultados do teste de patogenicidade, foi sequenciado um isolado de Pseudomonas syringae (Psa3) P155, que abriga a uma série de genes de virulência e resistência, elementos candidatos CRISPR, sequências relacionadas a profagos, modificações na metilação, ilhas genômicas, e também um plasmídeo. O mais importante foram os genes de resistência ao cobre, copA, copB, copC, copD e copZ, bem como, o gene de resistência aminoglicosídea ksgA identificados na estirpe P155, os quais representariam uma ameaça à produção de kiwi. A sequência completa relatada fornecerá informações valiosas para uma melhor compreensão da estrutura genética e as características patogênicas do genoma de P155.


Subject(s)
Virulence , Actinidia , Pseudomonas syringae , Whole Genome Sequencing
8.
Enzyme Microb Technol ; 101: 17-23, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28433186

ABSTRACT

We characterized ramie leaf ß-amylase, and determined its thermostability and kinetic parameters. The enzyme was purified 53-fold using ammonium sulfate fractionation (40-60% saturation), anion exchange chromatography on DEAE-cellulose and gel permeation chromatography on Superdex-200. The purified enzyme was identified as ß-amylase with molecular mass of 42kD. The enzyme displayed Km and kcat values for soluble potato starch of 1.1mg/mL and 7.8s-1, respectively. The enzyme had a temperature optimum of 65°C, and its activity at 70°C was 92% of that at the optimal temperature after a 15-min incubation. Furthermore, enzyme activity was stable during treatment at 55°C for 60min but was inactivated rapidly at >75°C. This thermal behavior indicates that ramie leaf ß-amylase has excellent intermediate temperature-stable enzyme properties for the baking and bio-industries. Inactivation of the enzyme followed first-order kinetics in the range of 55-80°C. The enthalpy change of thermal inactivation (ΔH‡), ΔG‡, and ΔS‡ were 237.2kJ/mol, 107.7kJ/mol, and 0.39kJ/molK at 333K, respectively. The D-value at 65°C (=110min) and the z-value (=9.4°C) are given for food processing.


Subject(s)
Boehmeria/enzymology , Plant Proteins/antagonists & inhibitors , Plant Proteins/metabolism , beta-Amylase/antagonists & inhibitors , beta-Amylase/metabolism , Electrophoresis, Polyacrylamide Gel , Enzyme Stability , Food Technology , Hot Temperature , Kinetics , Molecular Weight , Plant Leaves/enzymology , Plant Proteins/chemistry , beta-Amylase/chemistry
9.
Int J Pharm ; 522(1-2): 110-118, 2017 Apr 30.
Article in English | MEDLINE | ID: mdl-28242375

ABSTRACT

Gambogic acid (GA) is a potential anti-cancer agent with poor water-solubility, whereas heparin has anti-angiogenesis effects with good hydrophilicity. In this study, GA grafted low molecular weight heparin (GA-LMWH) was prepared and self-assembled into micelles in aqueous solution to improve the solubility and antitumor effects against hepatocellular carcinoma. The substitution of GA-LMWH is 27.5±0.2%. The micelles had a mean size of 190.4±10.8nm, a low critical micelle concentration of 2.4±0.2µgmL-1, and the highest area under the concentration-time curve and mean retention time in the liver compared to the heart, spleen, lung and kidney (p<0.05). The targeting efficiency of micelles to the liver is 2.1-times higher than that of the GA solution. GA-LMWH micelles were administered intravenously and significantly improved liver function, decreased cell lesions in hepatic tissue, inhibited the expression of CD105 and prolonged survival time of hepatocellular carcinoma model compared with groups treated with normal saline or GA solution. These results suggest that GA-LMWH micelles may improve anti-cancer effects by targeting the delivery of GA to the liver and enhancing the anti-angiogenesis effect.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Carcinoma, Hepatocellular/drug therapy , Drug Delivery Systems/methods , Heparin, Low-Molecular-Weight/chemistry , Heparin, Low-Molecular-Weight/pharmacology , Liver Neoplasms, Experimental/drug therapy , Xanthones/chemistry , Xanthones/pharmacology , Administration, Intravenous , Angiogenesis Inhibitors/chemistry , Animals , Antineoplastic Agents, Phytogenic/pharmacokinetics , Drug Carriers , Heparin, Low-Molecular-Weight/pharmacokinetics , Liver Function Tests , Male , Mice , Micelles , Particle Size , Structure-Activity Relationship , Survival Analysis , Tissue Distribution , Xanthones/pharmacokinetics
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 394-402, 2017 Feb.
Article in Chinese | MEDLINE | ID: mdl-30264968

ABSTRACT

The energy received through remote sensing sensors contains the amount of reflected solar energy and emitted energy of objects in middle-wave infrared (MWIR, 3~5 µm). Usually, the reflected solar energy is weak in MWIR spectrum. In some certain situations like sun glint area in sea surface, however, the energy is relatively significant and less sensitive to atmospheric effects. Meanwhile, for the satellite sensor which equipped with onboard calibration system, its onboard radiation performance of MWIR(using blackbody calibration)is quite stable. Therefore, the MWIR reflectance in sea surface glint area can be considered as a reference for cross-calibration between the solar reflected bands. Based on this idea, this paper constructed an improved non-linear split window model that is suitable for VIIRS (visible infrared imaging radiometer) MWIR band and used this model to calculate the MWIR reflectance of sun glint area in southern Indian Ocean. This model made statistics, getting the relationship between the reflectance of VIIRS M12 and M13 bands at first, and then used the non-linear split window algorithm to calculate the actual sea surface reflectance. The uncertainty of the simulation model was 0.83%. On this basis, this paper calculated sea surface reflectance of selected sample regions based on the data of VIIRS M12 band (center wavelength: 3.697 µm) in sun glint areas. And then verified the reflectance accuracy by two methods, getting the two accuracies were about 0.239% and 0.23%, respectively. It proves that the calculation model in this paper can greatly improve the accuracy compared to the situation when the sea surface reflectance is between M12 and M13 which are assumed to be equal (accuracy of 2.48% and 1.03%, respectively). It also indicated that the model is feasible and effective to calculate the reflectance in sea surface glint area with VIIRS M12 MWIR band, and the accuracy can meet the requirements of MWIR sea surface reflectance as a calibration reference among bands.

11.
Oncotarget ; 8(66): 110552-110565, 2017 Dec 15.
Article in English | MEDLINE | ID: mdl-29299168

ABSTRACT

Thyroid cancer is one of the most prevalent endocrine neoplasm. The present study examined the effects of Colorectal Neoplasia Differentially Expressed (CRNDE) on the progression of papillary thyroid cancer (PTC), and explored the underlying molecular mechanisms. Quantitative real-time PCR was used to detect CRNDE, miR-384 and pleiotrophin (PTN) mRNA expression. Western blot was used to measure PTN protein levels. Cell proliferation, cell growth, cell invasion and migration of PTC cells were determined by CCK-8, colony formation, transwell invasion and migration assays, respectively. CRNDE was up-regulated in PTC tissues and cell lines. Overexpression of CRNDE promoted BCPAP cell proliferation, invasion and migration, while knock-down of CRNDE suppressed K1 cell proliferation, invasion and migration. CRNDE negatively regulated the expression of miR-384 in PTC cells, which was further confirmed by luciferase reporter assay. MiR-384 was down-regulated and inversely correlated with CRNDE expression in PTC tissues. MiR-384 suppressed cell proliferation, invasion and migration in PTC cells, and enforced expression of miR-384 attenuated the oncogenic effects of CRNDE in PTC cells. PTN was predicted as a downstream target of miR-384, which was confirmed by luciferase reporter assay, and PTN was up-regulated in PTC tissues, and was negatively correlated with miR-384 expression and positively correlated with CRNDE expression in PTC tissues. In summary, our results suggested that the CRNDE/miR-384/PTN axis may play an important role in the regulation of PTC progression, which provides us with new insights into understanding the PTC.

12.
Yao Xue Xue Bao ; 50(5): 574-8, 2015 May.
Article in Chinese | MEDLINE | ID: mdl-26234139

ABSTRACT

N-Benzyl matrinol was obtained by hydrolysis, benzylation and reduction reaction from matrine. A series of hybrids (8a-8n) from (phenylsulfonyl)furoxan and N-benzyl matrinol were synthesized and biologically evaluated as anti-hepatocellular carcinoma agents. All target compounds were evaluated for anti-proliferative activity against human hepatocellular Bel-7402, SMMC-7721, Bel-7404, and HepG2 cells in vitro by MTT method. The results indicated that all of these compounds had potent anti-proliferative activity which were more potent than their parent compound and 5-FU, especially 8a-8h and 8j showed the strongest anti-HCC HepG2 cell activity with IC50 values of 0.12-0.93 µmol x L(-1).


Subject(s)
Antineoplastic Agents/pharmacology , Oxadiazoles/pharmacology , Carcinoma, Hepatocellular , Fluorouracil , Hep G2 Cells , Humans , Liver Neoplasms
13.
Bioorg Med Chem Lett ; 22(1): 289-92, 2012 Jan 01.
Article in English | MEDLINE | ID: mdl-22153338

ABSTRACT

A series of novel derivatives of gambogic acid (GA) were synthesized and evaluated for their in vitro cytotoxicity against human hepatocellular carcinoma (HCC) cells. All derivatives showed better aqueous solubility than GA, and compounds 3a, 3e, and 3f displayed potent inhibition of HCC cell proliferation (IC(50): 0.045-0.59 µM on Bel-7402 cells and 0.067-0.94 µM on HepG2 cells) superior to GA and taxol. Additionally, the most potent compound 3e did not affect significantly the proliferation of non-tumor liver cells, suggesting that it might selectively inhibit HCC proliferation. Furthermore, 3e induced high frequency of Bel-7402 cell apoptosis. Our findings suggest that these novel GA derivatives may hold a great promise as therapeutic agents for the intervention of human HCC.


Subject(s)
Carcinoma, Hepatocellular/drug therapy , Liver Neoplasms/drug therapy , Xanthones/chemistry , Apoptosis , Cell Line, Tumor , Cell Proliferation , Chemistry, Pharmaceutical/methods , Dose-Response Relationship, Drug , Drug Design , Drug Screening Assays, Antitumor/methods , Hep G2 Cells , Humans , Inhibitory Concentration 50 , Models, Chemical , Solubility
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