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1.
Chemosphere ; 361: 142531, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38838864

ABSTRACT

In site chromium (Cr) contaminated soil characterized by high alkalinity and carbonate content, protons are not effectively targeted for Cr(III) mobilization but rather accelerate the reduction of easily transportable Cr(VI) within the acidification electrokinetic (EK) system. As an alternative, the highly alkaline extraction conditions (HAECs) maintained by anolyte regulation are explored owing to the ability to desorb strong binding Cr(VI) and form anionic Cr(III)-hydroxides (Cr(OH)4-, Cr(OH)52-). The results demonstrate that HAECs were more efficient in mobilizing ions in severe alkalinity and electrical conductivity soil compared to organic acid acidifying extraction conditions (OAECs). Simultaneously, a limited amount of soluble Cr(III) was produced; however, its transportation was hindered and more noticeable in the case of Cr(VI), displaying a distinct retention phase within the intermediate soil chamber. The antagonistic interplay between electromigration and electroosmotic flow was considered the main responsible factor. The conversion intensity of Cr(VI) to Cr(III) was inhibited at HAECs. The promising mobilization and low conversion intensity contributed to total Cr removal. At HAECs, enhanced electromigration and electroosmotic flow combined with a favorable oxidation environment may facilitate in situ delivery of oxidants, offering practical implications for the EK detoxification of high alkalinity site soil contaminated with Cr. The practicability of HAECs is likely to be enhanced when the cost-benefit balance of providing a simultaneous energy supply during site treatment is resolved.


Subject(s)
Chromium , Soil Pollutants , Soil , Chromium/chemistry , Soil Pollutants/analysis , Soil Pollutants/chemistry , Soil/chemistry , Hydrogen-Ion Concentration , Environmental Restoration and Remediation/methods , Oxidation-Reduction
2.
Eur J Med Chem ; 217: 113372, 2021 May 05.
Article in English | MEDLINE | ID: mdl-33744689

ABSTRACT

Diabetes mellitus is one of the most challenging threats to global public health. To improve the therapy efficacy of antidiabetic drugs, numerous drug delivery systems have been developed. Polyethylene glycol (PEG) is a polymeric family sharing the same skeleton but with different molecular weights which is considered as a promising material for drug delivery. In the delivery of antidiabetic drugs, PEG captures much attention in the designing and preparation of sustainable and controllable release systems due to its unique features including hydrophilicity, biocompatibility and biodegradability. Due to the unique architecture, PEG molecules are also able to shelter delivery systems to decrease their immunogenicity and avoid undesirable enzymolysis. PEG has been applied in plenty of delivery systems such as micelles, vesicles, nanoparticles and hydrogels. In this review, we summarized several commonly used PEG-contained antidiabetic drug delivery systems and emphasized the advantages of stimuli-responsive function in these sustainable and controllable formations.


Subject(s)
Diabetes Mellitus/drug therapy , Drug Delivery Systems , Hypoglycemic Agents/therapeutic use , Polyethylene Glycols/chemistry , Drug Carriers/chemistry , Humans , Hypoglycemic Agents/chemistry , Micelles , Molecular Structure
3.
Eur J Med Chem ; 212: 113105, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33385835

ABSTRACT

Macro biomolecules are of vital importance in regulating the biofunctions in organisms, in which proteins (including peptides when mentioned below) and nucleic acids (NAs) are the most important. Therefore, these proteins and NAs can be applied as "drugs" to regulate the biofunctions from abnormal to normal. Either for proteins and NAs, the most challenging thing is to avoid the biodegradation or physicochemical degradation before they reach the targeted location, and then functions as complete functional structures. Hence, appropriate delivery systems are very important which can protect them from these degradations. Cyclodextrins (CDs) based delivery systems achieved mega successes due to their outstanding pharmaceutical properties and there have been several reviews on CDs based small molecule drug delivery systems recently. But for biomolecules, which are getting more and more important for modern therapies, however, there are very few reviews to systematically summarize and analyze the CDs-based macro biomolecules delivery systems, especially for proteins. In this review, there were some of the notable examples were summarized for the macro biomolecules (proteins and NAs) delivery based on CDs. For proteins, this review included insulin, lysozyme, bovine serum albumin (BSA), green fluorescent protein (GFP) and IgG's, etc. deliveries in slow release, stimulating responsive release or targeting release manners. For NAs, this review summarized cationic CD-polymers and CD-cluster monomers as NAs carriers, notably, including the multicomponents targeting CD-based carriers and the virus-like RNA assembly method siRNA carriers.


Subject(s)
Cyclodextrins/chemistry , Drug Delivery Systems , Nucleic Acids/chemistry , Peptides/chemistry , Proteins/chemistry , Drug Carriers/chemistry , Humans , Macromolecular Substances/chemistry
4.
Sci Total Environ ; 759: 143512, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33221012

ABSTRACT

Carbon tax is a powerful incentive to mitigate carbon emissions and promote energy revolutions. It is of vital importance to systematically explore and examine the socio-economic impacts of levying a carbon tax, such that desired compromises among socio-economic and environmental objectives can be identified. In order to fill the research gap on the stepped carbon tax, this study is to develop a factorial computable general equilibrium (FCGE) model for examining the interactive effects of multiple policy options (e.g., grouping of emission intensity/level, and relevant tax rates), and supporting the formulation of desired carbon-mitigation policies. It is discovered that (1) carbon tax of 18.37 to 38.25 Yuan/ton is a reasonable policy alternative for China; (2) the stepped carbon tax (high level on coal-related fuels) is more efficiency than conventional carbon tax policy; (3) the positive effects for reducing carbon emission intensity can be strengthened with an increasing step range; (4) interactive effects between stepped carbon taxes on coal-related energies and crude oil related energies should be jointly considered by the policy makers.

5.
J Environ Manage ; 269: 110721, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32560982

ABSTRACT

The carbon-price mechanism has been proved to be an effective measure for promoting energy revolution and mitigating climate change. It is of vital importance to develop optimal energy development strategy for electric power-dependent regions by considering the complex interaction among carbon price, carbon emission control, and carbon-responsibility transfer. In order to fill the research gap on the optimal choice of carbon-price mechanism at the urban level, this study is the first attempt to express uncertainties embodied in the carbon price mechanism as interval values, probability distribution and downside risks. The developed risk-aversion-based interval two-stage stochastic programming (RITSP) model is effective in analyzing the effect of internal and electric-transmission related carbon-tax on power system structure. It is discovered that carbon compensation policy for imported electricity is more suitable for Tianjin's power system development. Tianjin would primarily purchase electricity from Inner-Mongolia. With the increase of carbon emission tax, Tianjin would import increasing proportion of electricity from Gansu. Due to the limited endowment of renewable energy in Tianjin, the impact of carbon emission limitations on the renewable energy power generation structure of is trivial, and it has a greater impact on stimulating the development of CCS technology. What's more, Tianjin's future power system planning is more inclined to develop CCS rather than renewable energy.


Subject(s)
Carbon , Electricity , China , Renewable Energy , Uncertainty
6.
Molecules ; 26(1)2020 Dec 31.
Article in English | MEDLINE | ID: mdl-33396550

ABSTRACT

A series of multi-substituted isatin derivatives were synthesized using the powerful Sandmeyer reaction. The structures of these derivatives were confirmed by 1H-NMR, 13C-NMR, and HR-MS. Inhibition of proliferation activities of these derivatives against human leukemia cells (K562), human hepatocellular carcinoma cells (HepG2) and human colon carcinoma cells (HT-29) were evaluated in vitro using the MTT assay. Among the series, compound 4l exhibited strong antiproliferatory activities against K562, HepG2 and HT-29 cells with IC50 values of 1.75, 3.20, and 4.17 µM, respectively. The morphological, growth inhibitory and apoptosic effects of compound 4l in K562 cells, wound healing effect in HepG2 cells, and tube formating effect in matrix gel of HUVEC cells were evaluated consequently. All results indicated that compound 4l could be used as a potential antitumor agent in further investigations.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Cell Proliferation/drug effects , Isatin/chemistry , Neoplasms/drug therapy , Drug Design , HT29 Cells , Hep G2 Cells , Human Umbilical Vein Endothelial Cells , Humans , K562 Cells , Molecular Structure , Neoplasms/pathology , Structure-Activity Relationship
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