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1.
Int J Biol Macromol ; 263(Pt 2): 130473, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423437

RESUMO

Momordica Charantia Polysaccharide (MCP) is a key bioactive compound derived from bitter melon fruit. This review summarizes the advancements in MCP research, including extraction techniques, biological activities, and mechanisms. MCP can be extracted using various methods, and has demonstrated hypoglycemic, antioxidant, anti-inflammatory, and immunoregulatory effects. Research suggests that MCP may regulate metabolic enzymes, oxidative stress reactions, and inflammatory pathways. The review highlights the potential applications of MCP in areas such as anti-diabetes, antioxidant, anti-inflammatory, and immunoregulatory research. Future research should focus on elucidating the molecular mechanisms of MCP and optimizing extraction methods. This review provides a foundation for further research and utilization of MCP.


Assuntos
Antioxidantes , Momordica charantia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Anti-Inflamatórios
2.
Biomed Pharmacother ; 168: 115726, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37862973

RESUMO

Momordica charantia polysaccharide (MCP) is a potential drug for the prevention and alleviation of diabetes mellitus (DM) and diabetic retinopathy (DR). This study aimed to investigate the potential protective effects of MCP on early-stage DR and explore the underlying mechanisms. The model group (DM group) and treatment group (D+H group) were established by inducing type 1 DM using a single dose of streptozotocin (STZ) at 60 mg/kg. After modeling, the D+H group was orally administered a 500 mg/kg dose of MCP solution once daily for 12 weeks. Monitoring of systemic indicators (FBG, body weight, general condition) and retinal tissue inflammation and apoptosis (HE staining, IL-6, MCP-1, TNF-α, VEGF, NF-κB, Caspase-3) in this study demonstrated that MCP intervention alleviated both DM and DR. MCP improved the body weight and general condition of DM rats by reducing FBG levels. It also enhanced the anti-inflammatory and anti-apoptotic capabilities of retinal neurons and microvessels by modulating the actions of cytokines, thereby further regulating the inflammation and apoptosis of retinal neurons and microvessels. The underlying mechanisms may be associated with the downregulation of NF-κB and Caspase-3 pathway protein expression, as well as the downregulation of mRNA expression of NF-κB and Caspase-3 pathway genes. Further research is needed to elucidate the potential mechanisms underlying the protective effects of MCP on DR. MCP may emerge as a selective medication for the prevention and alleviation of DM and a novel natural medicine for the prevention and alleviation of DR.


Assuntos
Diabetes Mellitus Tipo 1 , Retinopatia Diabética , Momordica charantia , Ratos , Animais , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/prevenção & controle , Retinopatia Diabética/genética , NF-kappa B/uso terapêutico , Caspase 3 , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Inflamação/tratamento farmacológico , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Peso Corporal
3.
Microbiol Spectr ; : e0082923, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698429

RESUMO

Acute pancreatitis (AP) is a type of digestive system disease with high mortality. Previous studies have shown that gut microbiota can participate in developing and treating acute pancreatitis by affecting the host's metabolism. In this study, we followed 20 AP patients to generate longitudinal gut microbiota profiles and activity during disease (before treatment, on the third day of treatment, and 1 month after discharge). We analyzed species composition and metabolic pathways' changes across the treatment phase, severity, and etiology. The diversity of the gut microbiome of patients with AP did not show much variation with treatment. In contrast, the metabolic functions of the gut microbiota, such as the essential chemical reactions that produce energy and maintain life, were partially reinstated after treatment. The severe AP (SAP) patients contained less beneficial bacteria (i.e., Bacteroides xylanisolvens, Clostridium lavalense, and Roseburia inulinivorans) and weaker sugar degradation function than mild AP patients before treatment. Moreover, etiology was one of the drivers of gut microbiome composition and explained the 3.54% variation in species' relative abundance. The relative abundance of pathways related to lipid synthesis was higher in the gut of hyperlipidemia AP patients than in biliary AP patients. The composition and functional profiles of the gut microbiota reflect the severity and etiology of AP. Otherwise, we also identified bacterial species associated with SAP, i.e., Oscillibacter sp. 57_20, Parabacteroides johnsonii, Bacteroides stercoris, Methanobrevibacter smithii, Ruminococcus lactaris, Coprococcus comes, and Dorea formicigenerans, which have the potential to identify the SAP at an early stage. IMPORTANCE Acute pancreatitis (AP) is a type of digestive system disease with high mortality. Previous studies have shown that gut microbiota can participate in the development and treatment of acute pancreatitis by affecting the host's metabolism. However, fewer studies acquired metagenomic sequencing data to associate species to functions intuitively and performed longitudinal analysis to explore how gut microbiota influences the development of AP. We followed 20 AP patients to generate longitudinal gut microbiota profiles and activity during disease and studied the differences in intestinal flora under different severities and etiologies. We have two findings. First, the gut microbiota profile has the potential to identify the severity and etiology of AP at an early stage. Second, gut microbiota likely acts synergistically in the development of AP. This study provides a reference for characterizing the driver flora of severe AP to identify the severity of acute pancreatitis at an early stage.

4.
Polymers (Basel) ; 15(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37571077

RESUMO

To guide therapeutic strategies and to monitor the state changes in the disease, a low-cost, portable, and easily fabricated microfluidic-chip-integrated three-dimensional (3D) microchamber was designed for capturing and analyzing breast cancer cells. Optimally, a colorimetric sensor array was integrated into a microfluidic chip to discriminate the metabolites of the cells. The ultraviolet polymerization characteristic of poly(ethylene glycol) diacrylate (PEGDA) hydrogel was utilized to rapidly fabricate a three-layer hydrogel microfluidic chip with the designed structure under noninvasive 365 nm laser irradiation. 2-Hydroxyethyl methacrylate (HEMA) was added to the prepolymer in order to increase the adhesive capacity of the microchip's surface for capturing cells. 1-Vinyl-2-pyrrolidone (NVP) was designed to improve the toughness and reduce the swelling capacity of the hydrogel composite. A non-toxic 3D hydrogel microarray chip (60 mm × 20 mm × 3 mm) with low immunogenicity and high hydrophilicity was created to simulate the real physiological microenvironment of breast tissue. The crisscross channels were designed to ensure homogeneous seeding density. This hydrogel material displayed excellent biocompatibility and tunable physical properties compared with traditional microfluidic chip materials and can be directly processed to obtain the most desirable microstructure. The feasibility of using a PEGDA hydrogel microfluidic chip for the real-time online detection of breast cancer cells' metabolism was confirmed using a specifically designed colorimetric sensor array with 16 kinds of porphyrin, porphyrin derivatives, and indicator dyes. The results of the principal component analysis (PCA), the hierarchical cluster analysis (HCA), and the linear discriminant analysis (LDA) suggest that the metabolic liquids of different breast cells can be easily distinguished with the developed PEGDA hydrogel microfluidic chip. The PEGDA hydrogel microfluidic chip has potential practicable applicability in distinguishing normal and cancerous breast cells.

5.
Small ; 19(39): e2302583, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37236201

RESUMO

The slow solid diffusion dynamics of sodium ions and the side-reaction of sodium metal plating at low potential in the hard carbon anode of sodium ion batteries (SIBs) pose significant challenges to the safety manipulation of high-rate batteries. Herein, a simple yet powerful fabricating method is reported on for "egg puff"-like hard carbon with few N doping using rosin as a precursor via liquid salt template-assisted and potassium hydroxide dual activation. The as-synthesized hard carbon delivers promising electrochemical properties in the ether-based electrolyte especially at high rates, based on the absorption mechanism of fast charge transfer. The optimized hard carbon exhibits a high specific capacity of 367 mAh g-1 at 0.05 A g-1 and 92.9% initial coulombic efficiency (ICE), 183 mAh g-1 at 10 A g-1 , and ultra-long cycle stability of reversible discharge capacity of 151 mAh g-1 after 12,000 cycles at 5 A g-1 with the average coulombic efficiency of ≈99% and the decay of 0.0026% per cycle. These studies will undoubtedly provide an effective and practical strategy for advanced hard carbon anode of SIBs based on adsorption mechanism.

6.
Adv Sci (Weinh) ; 10(14): e2207751, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36938864

RESUMO

Zinc borates have merits of low voltage polarization and suitable redox potential, but usually suffer from low rate capability and poor cycling life, as an emerging anode candidate for Na+ storage. Here, a new intercalator-guided synthesis strategy is reported to simultaneously improve rate capability and stabilize cycling life of N, B co-doped carbon/zinc borates (CBZG). The strategy relies on a uniform dispersion of precursors and simultaneously stimulated combustion activation and solid-state reactions capable of scalable preparation. The Na+ storage mechanism of CBZG is studied: 1) ex situ XRD and XPS demonstrate two-step reaction sequence of Na+ storage: Zn6 O(OH)(BO3 )3 +Na+ +e- ↔3ZnO+Zn3 B2 O6 +NaBO2 +0.5H2 ①, Zn3 B2 O6 +6Na+ +6e- ↔3Zn+3Na2 O+B2 O3 ②; reaction ① is irreversible in ether-based electrolyte while reversible in ester-based electrolyte. 2) Electrochemical kinetics reveal that ether-based electrolyte possesses faster Na+ storage than ester-based electrolyte. The composite demonstrates an excellent capacity of 437.4 mAh g-1 in a half-cell, together with application potential in full cells (discharge capacity of 440.1 mAh g-1 and stable cycle performance of 2000 cycles at 5 A g-1 ). These studies will undoubtedly provide an avenue for developing novel synthetic methods of carbon-based borates and give new insights into the mechanism of Na+ storage in ether-based electrolyte for the desirable sodium storage.

7.
Adv Sci (Weinh) ; 10(13): e2207355, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36905241

RESUMO

Low-contents/absence of non-electrochemical activity binders, conductive additives, and current collectors are a concern for improving lithium-ion batteries' fast charging/discharging performance and developing free-standing electrodes in the aspects of flexible/wearable electronic devices. Herein, a simple yet powerful fabricating method for the massive production of mono-dispersed ultra-long single-walled carbon nanotubes (SWCNTs) in N-methyl-2-pyrrolidone solution, benefiting from the electrostatic dipole interaction and steric hindrance of dispersant molecules, is reported. These SWCNTs form a highly efficient conductive network to firmly fix LiFePO4  (LFP) particles in the electrode at low contents of 0.5 wt% as conductive additives. The binder-free LFP/SWCNT cathode delivers a superior rate capacity of 161.5 mAh g-1 at 0.5 C and 130.2 mAh g-1 at 5 C, with a high-rate capacity retention of 87.4% after 200 cycles at 2 C. The self-supporting LFP/SWCNT cathode shows excellent mechanical properties, which can withstand at least 7.2 MPa stress and 5% strain, allowing the fabrication of high mass loading electrodes with thicknesses up to 39.1 mg cm-2 . Such self-supporting electrodes display conductivities up to 1197 S m-1 and low charge-transfer resistance of 40.53 Ω, allowing fast charge delivery and enabling near-theoretical specific capacities.

8.
RSC Adv ; 12(46): 29852-29864, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36321088

RESUMO

The rheological and filtration performance of drilling fluids greatly depends on the additives used. To address the negative impact on the drilling fluid performance stemming from electrolyte contamination, a sustainable sodium alginate (SA) biopolymer was employed as an additive in water-based drilling fluids to overcome the performance deterioration caused by the polyelectrolyte effect under salt contamination. The results demonstrated that SA performs better than sodium carboxymethyl cellulose (Na-CMC) and polyanionic cellulose (PAC-LV), the widely used drilling fluid additives. Although exposed to highly concentrated salt contamination, the addition of SA can mitigate viscosity variation and maintain a lower filtration volume of a base fluid (BF), whereas an advanced variation in CMC/BF and PAC/BF was observed. The possible rheology and filtration mechanism of SA under highly concentrated salt contamination were investigated through zeta potential, particle size distribution, and scanning electron microscopy (SEM). The results revealed that the anchoring groups on the SA molecular chain enable them to strongly adsorb on the negatively charged bentonite surface via hydrogen and ionic bond interactions, leading to a significant improvement in both rheological and filtration performance. Therefore, SA with excellent salt tolerance and sustainability confers practical applicability that could extend to the preparation of saltwater-based and other inhibitive drilling fluids.

9.
Langmuir ; 38(41): 12539-12550, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36213955

RESUMO

Wettability alteration of the shale surface is a potential strategy to address wellbore instability issues arising from shale hydration. In this study, we have explored an oil-in-water (o/w) nanoemulsion, in which soluble silicate (lithium silicate and potassium methyl silicate) as the aqueous phase and organosilanes (3-methacryloxypropyltrimethoxysilane (KH570) and n-octyltriethoxysilane (n-OTES)) as the oil phase, as a shale inhibitor via forming a hydrophobic "artificial borehole shield" in situ on shale surfaces to maintain wellbore stability in high-temperature drilling operations. The shale dispersion test showed the highest shale recovery of nanoemulsion was up to 106.4% compared to that of water (20%), and recovered shale cuttings remained at the original integrity after hot rolling at 180 °C, indicating superior inhibition performance and resistance to elevated temperatures. Moreover, recovered shale cuttings manifested water repellency upon reimmersion in water, ascribed to the hydrophobic film, preventing water from permeating into the shale. The results of the contact angle measurement elucidated that the film wettability, from hydrophilic to superhydrophobic (ranging from 9.6-154°), can be achieved by altering the n-OTES-to-KH570 weight ratio from 0.2 to 2.25, and the film with the highest hydrophobicity (154°) and the lowest surface energy (3.17 mJ·m-2) can be obtained at a ratio of 1.3. Scanning electron microscopy images demonstrated that the superhydrophobic film was composed of tightly stacked reticulate nanofilaments with a diameter of 7-17 nm and several micrometers in length and overlapped well-distributed nanospheres with a diameter of 30 nm. X-ray diffraction and Fourier transform infrared spectroscopy confirmed the film was crystalline silica grafted with long-chain alkylsiloxane. It is assumed that the unique micronanostructure combined with the siloxane modification contributed to the hydrophobicity. Consequently, this study provides a potential alternative solution for wellbore stabilization in deep well drilling engineering by employing nanoemulsion as a shale hydration inhibitor via forming a protective film with controllable wettability. Furthermore, it can be conferred a practical application due to easily available, less hazardous, and cost-effective materials.

10.
Front Chem ; 10: 870564, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464228

RESUMO

Recently, sodium-ion batteries (SIBs) have attracted extensive attention as potential alternatives to lithium-ion batteries (LIBs) due to the abundance, even distribution, low cost, and environmentally friendly nature of sodium. However, sodium ions are larger than lithium ions so that the anode materials of LIBs are not suitable for SIBs. Therefore, many negative electrode materials have been investigated. Among them, Sb2S3-based nanomaterials have gradually become a research focus due to their high theoretical specific capacity, good thermal stability, simple preparation, and low price. In this review, the research progress of Sb2S3-based nanomaterials in the SIB field in recent years is summarized, including Sb2S3, Sb2S3/carbon composites, Sb2S3/graphene composites, and Sb2S3/MxSy composites. Furthermore, the challenges and prospects for the development of Sb2S3-based nanomaterials are also put forward. We hope this review will contribute to the design and manufacture of high-performance SIBs and promote its practical application.

11.
ACS Omega ; 6(37): 23988-23997, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34568677

RESUMO

Low-temperature co-current oxidizing pyrolysis, which can achieve high recovery of hydrocarbons without significant oil loss, has great potential to reduce the huge external energy required for oil shale conversion. However, this promising method is far from being fully understood, especially the unknown competing mechanism of different types of inorganic minerals in promoting or inhibiting hydrocarbon generation. In this study, the raw Huadian oil shale (HD-R), its carbonate-free (HD-C-F), and carbonate-silicate-free (HD-CS-F) samples obtained through acid treatment are used to investigate the effects of associated minerals on the oil shale co-current oxidizing pyrolysis. The results of shale oil yields of HD-R, HD-C-F, and HD-CS-F were 41.53, 22.38, and 33.97%, respectively, indicating that silicates inhibited, while carbonates catalyzed the formation of shale oil during the co-current oxidizing pyrolysis. Meanwhile, silicates increase the alkane content and decrease the alkene content in shale oil via promoting the combination of hydrogen radicals and alkyl radicals. On the contrary, alkali metals and alkaline earth metals in carbonates inhibit the binding activity of hydrogen radicals and alkyl radicals, concurrently enhancing the release of hydrogen-free radicals of alkyl radicals to form more alkenes. The removal of carbonates could enhance the conversion of organic carbon into hydrocarbons, and the silicates will strengthen the conversion process. It is hoped that this experiment can further enrich and perfect the basic theory of oil shale pyrolysis and provide a reliable reference for the pretreatment of oil shale conversion.

12.
Polymers (Basel) ; 13(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34578021

RESUMO

To overcome the negative impact on the rheological and filtration loss properties of drilling fluids caused by elevated temperature and salts contamination, which are common in ultradeep or geothermal drilling operations, it is imperative to develop highly efficient additives used in the water-based drilling fluid. In this study, a zwitterionic copolymer P (AM/DMC/AMPS/DMAM, ADAD) was synthesized by using acrylamide (AM), cationic monomer methacrylatoethyl trimethyl ammonium chloride (DMC), anionic monomer 2-acrylamide-2-methyl propane sulfonic acid (AMPS), and N,N-dimethylacrylamide (DMAM) through free radical copolymerization. The copolymer was characterized by 1H Nuclear Magnetic Resonance (NMR), Fourier transform infrared spectroscopy (FTIR), elemental analysis, thermogravimetric analysis (TGA), and zeta potential. The rheological behavior, filtration properties, and the performance exposure to salt or calcium contamination in water-based drilling fluid were investigated. The bentonite/polymer suspension showed improved rheological and filtration properties even after aging at 160 °C or a high concentration of salt and calcium. The filtration loss can be greatly reduced by more than 50% (from 18 mL to 7 mL) by the inclusion of 2.0 wt% copolymer, while a slight increase in the filtrate loss was observed even when exposed to electrolyte contamination. Particle size distribution and zeta potential further validate the idea that zwitterionic copolymer can greatly improve the stability of base fluid suspension through positive group enhanced anchoring on the clay surface and repulsion force between negative particles. Moreover, this study can be directed towards the design and application of zwitterionic copolymer in a water-based drilling fluid.

13.
ACS Omega ; 6(31): 20577-20589, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34396003

RESUMO

Effective control of shale swelling and lost circulation using drilling fluid is considered the dominant strategy for maintaining borehole stability, especially drilling operations in deep oil and gas wells. In this work, a hybrid silicate that contains lithium silicate and potassium methyl silicate (PMS) was employed as a film-forming additive to reduce shale hydration and filtration loss in the high-temperature drilling fluid. Scanning electron microscopy (SEM) results revealed that a dense quartz crystal film coating on the shale can be formed in a hybrid silicate solution when the temperature exceeds 150 °C. The in situ-formed film on the shale surface with a thickness of 60-130 µm was composed of fibrous crystalline silica. Furthermore, the aqueous hybrid silicate exhibited enhanced hydration inhibition ability by preventing water invasion of the formation. Aqueous hybrid silicate with a concentration of 0.5-3 wt % lithium silicate and 0.1-0.2 mol/L PMS was first chosen to obtain the optimum concentration according to the hydration inhibition ability and film formation characteristics. The hybrid silicate was added into a drilling fluid formulation applicable in high-pressure and high-temperature conditions, and the rheological characteristics and filtration properties were investigated. The results confirmed that drilling fluids with the addition of hybrid silicate can mitigate variation of viscosity and yield point before and after aging at 180 and 220 °C. Besides, the filtration behavior was also improved by adding hybrid silicate into the drilling fluid. A lower filtration loss was observed at the concentration of 1.0 wt % lithium silicate and 0.2 mol/L potassium methyl silicate, which showed 63 and 50% HPHT fluid loss reduction for unweighted and weighted formulations at 205 °C and 3.5 MPa, respectively. In addition, the drilling fluid featured stable rheological and filtration properties and excellent shale hydration inhibition characteristics when exposed to high temperatures, making it a promising candidate for drilling in deep oil and gas wells.

14.
Front Genet ; 11: 602922, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33519906

RESUMO

Colorectal cancer (CRC) is one of the most common neoplastic diseases worldwide. With a high recurrence rate among all cancers, treatment of CRC only improved a little over the last two decades. The mortality and morbidity rates can be significantly lessened by earlier diagnosis and prompt treatment. Available biomarkers are not sensitive enough for the diagnosis of CRC, whereas the standard diagnostic method, endoscopy, is an invasive test and expensive. Hence, seeking the diagnostic and prognostic biomarkers of CRC is urgent and challenging. With that order, we screened the overlapped differentially expressed genes (DEGs) of GEO (GSE110223, GSE110224, GSE113513) and TCGA datasets. Subsequent protein-protein interaction network analysis recognized the hub genes among these DEGs. Further functional analyses including Gene Ontology and KEGG pathway analysis and gene set enrichment analysis were processed to investigate the role of these genes and potential underlying mechanisms in CRC. Kaplan-Meier analysis and Cox hazard ratio analysis were carried out to clarify the diagnostic and prognostic role of these genes. In conclusion, our present study demonstrated that CCNA2, MAD2L1, DLGAP5, AURKA, and RRM2 are all potential diagnostic biomarkers for CRC and may also be potential treatment targets for clinical implication in the future.

15.
Mikrochim Acta ; 185(1): 51, 2017 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-29594383

RESUMO

This paper describes a voltammetric method for sensitive determination of specific sequences of DNA. The assay is based on three-dimensional nitrogen-doped graphene (3D-NG) which, due to its excellent electrical conductivity, provides a favorable microenvironment to retain the activity of immobilized probe single-stranded DNA and also facilitates electron transfer. The free-standing 3D-NG electrode was characterized by scanning electron microscopy, Raman and X-ray photoelectron spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Differential pulse voltammetry was applied to monitor DNA hybridization using Methylene Blue as an electrochemical indicator. Under optimal conditions, the peak currents (best measured at 0.28 V vs. Ag/AgCl) increase linearly with the logarithm of the concentrations of ssDNA in the 10 f. to 10 nM concentrations range, with a 3.5 f. detection limit (at a signal/noise ratio of 3). The biosensor exhibits good selectivity for ssDNA and can distinguish even single-base mismatches. The capability of the method was tested with spiked serum samples, and excellent reproducibility and stability is found. This indicates that the strategy is promising for use in clinical applications. Graphical abstract Three-dimensional nitrogen-doped graphene as an innovative and simple electrochemical DNA biosensor was fabricated and used in a biosensor that shows high sensitivity and good performance in the determination of target DNA in human serum samples.


Assuntos
Técnicas Biossensoriais/métodos , DNA/sangue , Técnicas Eletroquímicas/métodos , Grafite/química , DNA/química , DNA de Cadeia Simples/química , DNA de Cadeia Simples/metabolismo , Nitrogênio/química , Hibridização de Ácido Nucleico , Análise Espectral
16.
Sci Rep ; 5: 8290, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25656294

RESUMO

This paper proposes a novel energy-efficient oil shale pyrolysis process triggered by a topochemical reaction that can be applied in horizontal oil shale formations. The process starts by feeding preheated air to oil shale to initiate a topochemical reaction and the onset of self-pyrolysis. As the temperature in the virgin oil shale increases (to 250-300°C), the hot air can be replaced by ambient-temperature air, allowing heat to be released by internal topochemical reactions to complete the pyrolysis. The propagation of fronts formed in this process, the temperature evolution, and the reaction mechanism of oil shale pyrolysis in porous media are discussed and compared with those in a traditional oxygen-free process. The results show that the self-pyrolysis of oil shale can be achieved with the proposed method without any need for external heat. The results also verify that fractured oil shale may be more suitable for underground retorting. Moreover, the gas and liquid products from this method were characterised, and a highly instrumented experimental device designed specifically for this process is described. This study can serve as a reference for new ideas on oil shale in situ pyrolysis processes.

17.
Colloids Surf B Biointerfaces ; 123: 506-14, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25448719

RESUMO

Simultaneous delivery of multiple therapeutic agents is of great importance for effective chemotherapy due of its well-known drug synergism and suppression to chemoresistance. We report a new theranostic nanoformulation to shuttle multiple chemotherapeutic agents for successfully exterminating cancer cells. This strategy is based on the fabrication of magnetite doped mesoporous silica nanoparticles (MSNs) in which both internal porous and external surface of MSN are respectively exploited to load two different kinds of cytotoxic cargoes. Notably, an exceptionally high quantity (29%) of poorly hydrophobic drug camptothecin (CPT) is loaded into the nanopores of MSNs; however, in previous reports less than 1% loading efficiency is reported. Following CPT loading in the pores of MSNs, another unconventional but FDA approved arsenic trioxide (ATO) is conjugated onto the surface of nanocomposite via exploiting the thiophilic nature of ATO. Cell inhibition performance of dual drug nanoformulation is significantly higher than single drug formulation, possibly due to additional or synergistic effect, as low as 3 µg/ml of double drug nanocarrier were found effective to exterminate cancer cells. Besides drug delivery, the presence of superparamagnetic magnetite nanocrystals additionally empowers this system to be used as a contrast agent in magnetic resonance (MR) imaging for either monitoring diseased tissues or feedback of chemotherapy. We anticipate that the integration of combination therapy with nanotechnology coupled with versatile magnetic manipulation feature may prove a significant step forward toward the development of effective theranostic agents.


Assuntos
Arsenicais/química , Meios de Contraste/química , Sistemas de Liberação de Medicamentos/métodos , Óxidos/química , Dióxido de Silício/química , Trióxido de Arsênio , Camptotecina/química
18.
Genome Announc ; 2(5)2014 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-25342677

RESUMO

The complex microbiota of pit mud of solid-state fermentation reactors used for the production of Chinese liquor is responsible for producing one of the oldest distillates in the world. We apply a deep-sequencing approach to characterize the microbiota from pits that have been in use for up to 440 years.

19.
J Colloid Interface Sci ; 434: 1-8, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25151090

RESUMO

After a substantial advancement in single drug nanocarrier, nanomedicine now demands an integration of nanotechnology with combination therapy to achieve synergistic therapeutic effects. In this respect, a smart and multiple drug shuttling nanotheranostic system is developed which transport diverse kinds of anticancer drugs to cancer cells in a controlled and responsive manner respectively. Synthetically, a significantly high dose of hydrophobic camptothecin (CPT) is first loaded into the porous structure of quantum dots (CdS) coupled mesoporous silica nanocomposite. Subsequently, fluorescent doxorubicin (DOX) molecules are exclusively anchored onto the surface of CdS; as a result, the fluorescence of both CdS and DOX is quenched. Upon exposing to mildly acidic conditions, the fluorescence of both species is recovered, such fluorescent "on-off" states provides an added opportunity to real time sense drug release. In-vitro cell experiment reveals an excellent anticancer efficacy of drug cocktail, merely 3 µg/ml concentration of multiple drugs loaded nanocarrier reduces the cell viability to 30%. Furthermore, confocal imaging indicates a successful release of both therapeutic entities. We visualize that our newly fabricated multifunctional double drug-carrying nanoparticles can be a valuable addition to next generation of materials that simultaneously deliver cocktail of drugs with imaging functionality.


Assuntos
Antineoplásicos/administração & dosagem , Compostos de Cádmio/química , Camptotecina/administração & dosagem , Doxorrubicina/administração & dosagem , Nanocompostos/química , Pontos Quânticos/química , Dióxido de Silício/química , Sulfetos/química , Antineoplásicos/farmacologia , Camptotecina/farmacologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Doxorrubicina/farmacologia , Fluorescência , Humanos , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico , Porosidade
20.
Nanoscale ; 6(10): 5270-8, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24695417

RESUMO

Manganese oxide (Mn3O4) nanoparticles have recently emerged as a promising T1 contrast agent. In this study, for the first time, we demonstrated an interaction of Mn3O4 with a biological system, and found redox sensitive behavior of these paramagnetic nanoparticles in intracellular reducing environment. Inspired by these findings, we for the first time used this interaction for some therapeutic advantages and designed a versatile mesoporous silica based nanotheranostic system to realize redox-activated enhanced magnetic resonance imaging and responsive anticancer drug delivery. Contrary to previous reports, we firstly prepared high quality amine terminated hydrophilic Mn3O4 nanolids, without using multistep ligand exchange strategies. The resulting water stable and small-sized Mn3O4 nanolids were subsequently used as nanolids to cap drug loaded nanochannels of a porous carrier. Exposure to highly prevalent intracellular reducing environment resulted in the steady-state dissolution of these nanolids and attained an intelligent drug release. Furthermore, the redox receptive dissolution of paramagnetic Mn3O4 nanolids into Mn(2+) in turn increases the T1 signal to twofold, providing an added opportunity to even track the feedback of therapy. This study, in addition to simultaneously realizing drug delivery and imaging, also provides a new insight into the fate and interaction of manganese oxide nanoparticles with components of biological systems.


Assuntos
Compostos de Manganês , Teste de Materiais , Nanopartículas/química , Óxidos , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Humanos , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Óxidos/química , Óxidos/farmacologia
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