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1.
Analyst ; 148(18): 4463-4469, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37565801

RESUMO

A series of viscosity probes targeting different organelles were obtained using a single hemicyanine dye as the matrix structure. Specifically, probes 1a-d were obtained by introducing four amines (6-amino-2H-chromen-2-one, N-(2-aminoethyl)-4-methylbenzenesulfonamide, dodecan-1-amine and N,N diphenylbenzene-1,4-diamine) into the indole hemicyanine dye of the carboxylic acid with a D-π-A structure. Their maximum absorption wavelengths were in the range 570-586 nm and they had relatively large molar absorption coefficients, while their maximum emission wavelengths in the red light region were in the range 596-611 nm. Moreover, their fluorescence intensity in glycerol was 35-184 times higher than that in phosphate buffer solution (PBS). The lg(Fl) and lg η of probes 1a-d showed good linearity with high correlation coefficients according to the Förster-Hoffman equation. In addition, cell staining experiments demonstrated that 1a-c could target lysosomes, endoplasmic reticulum and mitochondria, respectively. They could also undergo viscosity-detectable changes in the corresponding organelles under the action of the corresponding ion carriers.


Assuntos
Corantes Fluorescentes , Organelas , Corantes Fluorescentes/química , Viscosidade , Lisossomos/química
2.
Org Biomol Chem ; 21(9): 1992-2000, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36789736

RESUMO

As an alkaloid, quinazolinone exhibits excellent biological properties; structurally, it also has the potential to construct fluorescent probes with conjugated structures. In this work, probes 5a-c and 6b were obtained by introducing quinazolone into aldehydes with different numbers of double bonds. Their absorption maxima were located at 420-540 nm and their emission maxima were at 500-600 nm in solvents of different polarities. In particular, probe 5c showed significant fluorescence enhancement with the increase in viscosity due to the limited intramolecular rotation, and its fluorescence intensity in glycerol was 37.8 times higher than that in water. Moreover, probes 5a-c and 6b containing the NH structure showed sensitive response to pH, and their fluorescence intensity in alkaline solution (pH 9-11) was suddenly enhanced, which was elucidated with the help of theoretical calculation. In addition, the cell experiments showed that probes 5a and 5b had the ability to target mitochondria and probes 5c and 6b targeted lysosomes in HeLa cells. Furthermore, the viscosity-sensitive probe 5c could be used for monitoring changes in lysosomal viscosity in HeLa cells, which had important guiding significance for designing multi-response fluorogenic probes and promoting the advancement of cancer diagnosis.


Assuntos
Corantes Fluorescentes , Quinazolinonas , Humanos , Células HeLa , Quinazolinonas/análise , Corantes Fluorescentes/química , Lisossomos/química , Solventes , Viscosidade
3.
Phys Chem Chem Phys ; 25(48): 32979-32988, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38031515

RESUMO

The exploration of high-quality and efficient electrocatalysts is crucial for the advancement of clean energy utilization and the development of energy conversion technologies. Recently, high-entropy alloys (HEA) have been actively explored as viable catalysts for water electrolysis due to their unique performance such as wide scope for compositional adjustments, excellent catalytic activity, and outstanding stability. However, the mechanism of synergistic oxygen evolution by HEA electrocatalysts at multiple sites has not been systematically and clearly demystified. Herein, in this paper, Pt is combined with inexpensive metals Ni, Cu, Fe, and Co to form a stable HEA structure. The synergistic catalytic mechanism of the PtNiFeCoCu HEA in the oxygen evolution reaction (OER) has been investigated, and the structure has been demonstrated to exhibit excellent hydrogen evolution reaction (HER) activity. The results suggest that the PtNiFeCoCu HEA catalyst achieved a lower overpotential of 0.44 V in the acidic OER, demonstrating that the PtNiFeCoCu HEA is a bifunctional electrocatalyst. In addition, oxygen intermediates are synergistically adsorbed on the surface of high-entropy alloys through multimetallic sites, which breaks the limitation of limited active sites. Further calculations indicated that the favorable OER activity of the catalyst originated from the strong associative coupling of the d orbitals of the synergistic metal sites to the 2p orbitals of the oxygen intermediates with enhanced synergistic effects. This work further elucidates the multisite synergistic catalysis of the PtNiFeCoCu HEA, providing a unique perspective to uncover the source of the high catalytic performance of HEA electrocatalysts.

4.
Phys Chem Chem Phys ; 25(44): 30296-30307, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37930335

RESUMO

The shortage of freshwater is a critical concern for contemporary society, and reverse osmosis desalination technology has gathered considerable attention as a potential solution to this problem. It has been recognized that the desalination process involving water flow through angstrom-sized pores has tremendous potential. However, it is challenging to obtain angstrom-sized pore structures with internal mass transfer and surface/interface properties matching the application conditions. Herein, a two-dimensional (2D) zeolite-like carbon structure (Carzeo-ANG) was constructed with unique angstrom-sized pores in the zeolite structure; then, the surface/interfacial transport behavior and percolation effect of the Carzeo-ANG desalination membrane were evaluated by density functional theory (DFT) calculations and classical molecular dynamics. The first-principles calculations in density functional theory were implemented through the Vienna ab initio simulation package (VASP), which is a commercial package for the simulation of carbon-based materials. The results show that Carzeo-ANG is periodically distributed with angstrom-sized pores (effective diameter = 5.4 Å) of dodecacyclic carbon rings, which ensure structural stability while maintaining sufficient mechanical strength. The remarkable salt-ion adsorption properties and mass transfer activity combined with the reasonable density distribution and free energy barrier for water molecules endow the membrane with superior desalination ability. At the pressure of 80 MPa, the rejection efficiency of Cl- and Na+ were 100% and 96.25%, and the membrane could achieve a water flux of 132.71 L cm-2 day-1 MPa-1. Moreover, the interconnected electronic structure of Carzeo-ANG imparts a self-cleaning effect.

5.
Phys Chem Chem Phys ; 25(34): 23249-23261, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37608737

RESUMO

It is estimated that the annual cost of corrosion in most countries accounts for 3-4% of gross domestic product, far exceeding the losses caused by natural disasters, prompting scientists to continuously search for high-performance anti-corrosion materials. Among these high-performance materials, two-dimensional carbon materials represented by graphene have received widespread attention due to their excellent chemical stability and anti-permeability. However, some studies have found that the poor ability of graphene to bind to the interface and the electrical coupling caused by metallicity make it possible to protect copper from corrosion only for a short period of time. To circumvent these issues, through phase behavior research, interface binding property simulation and corrosion mechanism exploration, we propose a more promising anti-corrosive three-dimensional (3D) biphenylene diamond-like carbon membrane (BP-DLC). The kinetic study results show that due to the Gibbs free energy of biphenylene structures below three layers being lower than 0, few-layer biphenylene can spontaneously generate phase transitions of limited size, forming a biphenylene diamond-like membrane and exhibiting superior mechanical properties and a certain degree of flexibility. Mechanical and electronic performance results further show that there is a strong bonding effect between BP-DLC and the metal surface, which further enhances the bistate heterostructure and prolongs the coating life of BP-DLC materials. Compared with pure graphene and Cu substrates, BP-DLC membranes exhibit stronger corrosion resistance by reducing porosity, increasing charge transfer and hindering the diffusion of corrosion ions to the substrate. This study provides a new strategy for constructing corrosion-resistant materials by designing long-term stable and highly corrosion-resistant diamond-like membranes.

6.
Phys Chem Chem Phys ; 25(41): 28326-28335, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37840459

RESUMO

The development of highly active oxygen evolution reaction (OER) catalysts with fast kinetics is crucial for the advancement of clean energy and fuel conversion to achieve a sustainable energy future. Recently, the synergistic effect of single-atom doping and multicomponent clusters has been demonstrated to significantly improve the catalytic activity of materials. However, such synergistic effects involving multi-electron and proton transfer processes are quite complex and many crucial mechanistic details need be well comprehended. We ingeniously propose a catalyst, (Fed-FeSc)@NiS2 (d stands for doping and c stands for clustering), with Fe and FeS acting synergistically on a NiS2 substrate. Specifically, fully dynamic monitoring of multiple active sites at the (Fed-FeSc)@NiS2 interface using metadynamics is innovatively performed. The results show that the rate determining step value at the overpotential of 1.23 V for the synergistic (Fed-FeSc)@NiS2 is 1.55 V, decreased by 6.67% and 35.29% compared to those of the independently acting single-atom doping and multi-clusters. The unique synergistic structure dramatically increases the d-band centre of the Fe site (-1.45 eV), endowing (Fed-FeSc)@NiS2 with more activity than conventional commercial Ir-C catalysts. This study provides insights into the synergistic effects of single-atom doping and multi-component clusters, leading to exploratory inspiration for the design of highly efficient OER catalysts.

7.
J Org Chem ; 87(15): 10385-10389, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35802521

RESUMO

Functional dyes with a chromeno[b]quinoline skeleton (3a-d) were synthesized by one-step cyclization between coumarin derivatives and aromatic amines under the promotion of anhydrous aluminum chloride in 41.2-45.8% yields. Their maximum absorption and emission wavelengths locate at 358-396 and 420-603 nm with large Stokes shifts (168-231 nm), and their intramolecular charge transfer has been corroborated by density functional theory calculations. Cell experiments have proved that the probes 3a-c possess the ability to target lipid droplets.


Assuntos
Gotículas Lipídicas , Quinolinas , Aminas , Cumarínicos , Corantes Fluorescentes
8.
Bioorg Med Chem Lett ; 48: 128239, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34229055

RESUMO

Five cyanine dyes (6a-e) with aza units were prepared by the reaction of pyridinum or quinolinium with suitable aldehydes. They present several remarkable features including large Stokes shift (235-282 nm), long emission wavelength (640-698 nm) and excellent selectivity. Moreover, probes 6a-b display obvious and sensitive fluorescent response to DNA and RNA in aqueous solution, and the quantum yield of probe 6a response to RNA increases from 0 to 8.9%. More importantly, probes 6c and 6e can effectively avoid DNA interference and only respond to RNA in aqueous solution. In addition, laser confocal cell experiment has showed that probe 6b can image the nucleolus of nucleic acids in HeLa cells.


Assuntos
DNA/análise , Corantes Fluorescentes/química , RNA/análise , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Estrutura Molecular , Soluções , Água/química
9.
Chemistry ; 25(49): 11432-11436, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31309625

RESUMO

We present strategies to tune the redox properties of polyoxometalate clusters to enhance the electron-coupled proton-buffer-mediated water splitting process, in which the evolution of hydrogen and oxygen can occur in different forms and is separated in time and space. By substituting the heteroatom template in the Keggin-type polyoxometalate cluster, H6 ZnW12 O40 , it is possible to double the number of electrons and protonation in the redox reactions (from two to four). This increase can be achieved with better matching of the energy levels as indicated by the redox potentials, compared to the ones of well-studied H3 PW12 O40 and H4 SiW12 O40 . This means that H6 ZnW12 O40 can act as a high-performance redox mediator in an electrolytic cell for the on-demand generation of hydrogen with a high decoupling efficiency of 95.5 % and an electrochemical energy efficiency of 83.3 %. Furthermore, the H6 ZnW12 O40 cluster also exhibits an excellent cycling behaviour and redox reversibility with almost 100 % H2 -mediated capacity retention during 200 cycles and a high coulombic efficiency >92 % each cycle at 30 mA cm-2 .

10.
Dig Dis Sci ; 64(10): 2955-2964, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31165380

RESUMO

BACKGROUND: There are many studies on submucosal injection materials, but their clinical use is restricted for various reasons. The objective of this study was to compare the feasibility and safety of injected EndoClot®SIS polysaccharide as a submucosal injection material (SFC) in ESD in the pig stomach to that of injected sigMAVisc™ or Eleview™. METHODS: Four pig stomachs were used for the ex vivo study. Eighteen pigs were used for the in vivo study. In the ex vivo study, four injections were made in the gastric submucosa to induce submucosal uplift and extend its duration. Tissue change was observed. The in vivo study was performed in 2 steps. First, 3 injections were made in the esophageal mucosa to induce submucosal uplift and extend its duration. Histological change was observed. Second, ESD was performed in the stomach by injecting EndoClot®SIS polysaccharide, sigMAVisc™, or Eleview™ (each, n = 6) as an SFC. The effects of these agents on wound healing were examined. We evaluated the efficacy and safety of endoscopic surgery after EndoClot®SIS polysaccharide injection. RESULTS: EndoClot®SIS polysaccharide produced a longer-lasting elevation with clearer margins than was achieved by sigMAVisc™, Eleview™, or 0.9% NaCl and thereby enabled precise ESD without complications, such as bleeding and perforation. No obvious histopathological damage was observed at the injection site on endoscopy and histology. CONCLUSION: Submucosally injected EndoClot®SIS polysaccharide increased the effective separation of the mucosa and submucosa and reduced surgical complications. Hence, EndoClot®SIS polysaccharide injection is a safe and effective submucosal injection material.


Assuntos
Ressecção Endoscópica de Mucosa , Mucosa Gástrica , Complicações Intraoperatórias/prevenção & controle , Polissacarídeos/farmacologia , Amido/análogos & derivados , Animais , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Excipientes/farmacologia , Mucosa Gástrica/patologia , Mucosa Gástrica/cirurgia , Injeções/métodos , Masculino , Modelos Animais , Cuidados Pré-Operatórios/métodos , Amido/farmacologia , Suínos , Porco Miniatura
11.
Angew Chem Int Ed Engl ; 58(10): 3092-3096, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30589160

RESUMO

Lithium metal anodes suffer from poor cycling stability and potential safety hazards. To alleviate these problems, Li thin-film anodes prepared on current collectors (CCs) and Li-free types of anodes that involve direct Li plating on CCs have received increasing attention. In this study, the atomic-scale design of Cu-CC surface lithiophilicity based on surface lattice matching of the bcc Li(110) and fcc Cu(100) faces as well as electrochemical achievement of Cu(100)-preferred surfaces for smooth Li deposition with a low nucleation barrier is reported. Additionally, a purposely designed solid-electrolyte interphase is created for Li anodes prepared on CCs. Not only is a smooth planar Li thin film prepared, but a uniform Li plating/stripping on the skeleton of 3D CCs is achieved as well by high utilization of the surface and cavities of the 3D CCs. This work demonstrates surface electrochemistry approaches to construct stable Li metal-electrolyte interphases towards practical applications of Li anodes prepared on CCs.

12.
J Am Chem Soc ; 140(8): 3134-3138, 2018 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-29425034

RESUMO

Investigations of the Ag (I)-substituted Keggin K3[H3AgIPW11O39] as a bifunctional Lewis acidic and basic catalyst are reported that explore the stabilization of Li2Sn moieties so that reversible redox reactions in S-based electrodes would be possible. Spectroscopic investigations showed that the Li2Sn-moieties can be strongly adsorbed on the {AgIPW11O39} cluster, where the Ag(I) ion can act as a Lewis acid site to further enhance the adsorption of the S-moieties, and these interactions were investigated and rationalized using DFT. These results were used to construct an electrode for use in a Li-S battery with a very high S utilization of 94%, and a coulometric capacity of 1580 mAh g-1. This means, as a result of using the AgPOM, both a high active S content, as well as a high areal S mass loading, is achieved in the composite electrode giving a highly stable battery with cycling performance at high rates (1050 and 810 mAh g-1 at 1C and 2C over 100 to 300 cycles, respectively).

13.
Parasitol Res ; 115(11): 4139-4152, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27469534

RESUMO

A preparation of niclosamide named 50 % wettable powder of niclosamide ethanolamine salt (WPN), the only chemical molluscicide available in China, has been widely used for Oncomelania hupensis control over the past 20 years, but its molluscicidal mechanism has not been elucidated yet. Recently, a derivative of niclosamide, the salt of quinoid-2',5-dichloro-4'-nitro-salicylanilide (Liu Dai Shui Yang An, LDS), has been proven to have equivalent molluscicidal effects as WPN but with lower cost and significantly lower toxicity to fish than WPN. In our previous study, gene expression profiling of O. hupensis showed significantly effects after these two molluscicides had been applied. This study was designed to use morphological and enzymological analyses to further elucidate the mechanism by which these molluscicides cause snail death. After WPN or LDS treatment, the number of mitochondria of O. hupensis was reduced and their cristae appeared unclear, heterochromatin gathered to be polarized, ribosome numbers of the rough endoplasmic reticulums (rERs) decreased, myofilaments in muscle cells became disordered and loose, and cytoplasm in some liver cells was concentrated. Damage of cell structures and organelles suggested inhibited movement ability and effects on liver and energy metabolism following treatment. In parallel, activities of enzymes related with carbohydrate metabolism were inhibited except lactate dehydrogenase (LDH) increased in muscle tissue, and activities of enzymes related with stress response increased followed by decreasing to lower levels than those of the H2O-treated group. This shift of carbohydrate metabolism patterns led to insufficient energy supply and lactic acid accumulation, and variations of nitric oxide synthase (NOS), alanine aminotransferase (ALT), and superoxide dismutase (SOD) during process of molluscicide treatment suggested a stress response of snail to the molluscicides at early stages and later fatal damage in liver and nervous system. In general, effects of WPN and LDS were similar although LDS-treated snails showed more serious damage in the liver and a stronger inhibition of enzymes related with aerobic respiration and stress response. This was consistent with the transcriptome profile obtained previously. However, considering enzyme activities at post-transcriptional and protein levels, comprehensive identification and annotation of potential enzyme-related genes and regulation pattern would be necessary to provide great benefit for understanding of potential mechanism of these molluscicides and even for future molluscicide development.


Assuntos
Moluscocidas/farmacologia , Niclosamida/análogos & derivados , Salicilanilidas/farmacologia , Caramujos , Animais , China , Fígado/ultraestrutura , Caramujos/anatomia & histologia , Caramujos/enzimologia , Transcriptoma
14.
Phys Chem Chem Phys ; 17(16): 10353-7, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25824866

RESUMO

A sulfide-based SEI layer was formed on the surface of a LiNi0.5Mn1.5O4 cathode by using a sulfolane-carbonate mixed solvent electrolyte, which led to an improvement in the electrochemical performance. Moreover, the thermal stability of the LiNi0.5Mn1.5O4 cathode was also significantly improved in the presence of the SEI layer. ARC (Accelerating Rate Calorimetry) tests showed that the self-heating rate of the delithiated LiNi0.5Mn1.5O4 material in the sulfolane-carbonate electrolyte was suppressed.

15.
Artigo em Zh | MEDLINE | ID: mdl-26931036

RESUMO

OBJECTIVE: To investigate the effect of lipopolysaccharide (LPS)-induced B cell activation on the development of Schistosoma japonicum. METHODS: Eighteen BALB/c nude mice deficient in T cells and 23 BALB/c SCID mice deficient in T and B cells were used in this study. Each was infected with 30 ± 1 S. japonicum cercariae. The nude (n=9, NL group) and SCID (n=12, SL group) mice then received 2-3 (every two weeks) intraperitoneal injections with LPS (100 µg/mL, 0.2 mL for each mouse). The remaining nude(n=9, N group) and SCID (n=11, S group) mice received PBS injection as control. The mice were sacrificed on days 28 and 36 after infection (n=4/5, 4/5, 5/6, 6/6 for N, NL, S and SL groups, respectively), and adult worms were collected by hepatic portal vein perfusion. The collecting rate of the adult worms was calculated, the body-length measured, and pairs of worms recorded. The liver tissue was collected and digested with 5% KOH, and the number of eggs per gram of liver tissue was calculated. The levels of TGF-ß, IFN-γ and IL-10 in peripheral blood were evaluated. Spleen cell suspension was prepared for detecting the proportion of regulatory B cells (Bregs) in splenic lymphocytes. RESULTS: On day 28 after infection, the body-lengths of male worms in NL and N groups were (7.65±2.85) mm and (5.28±1.64) mm (P<0.01), and those of female worms were (9.64±1.99) mm and (7.49±1.63) mm (P<0.01), respectively. On day 36 after infection, the number of eggs per gram of liver tissue was significantly higher in the NL group than in the N group (1 088±297 vs 715±404, P<0.05), and significantly lower in the SL group than in the S group (217±33 vs 573±160, P<0.01). The proportions of CD(hi)CD5(+)CD19(+) Bregs in N group on days 28 and 36 after infection were (12.73±0.96)% and (37.15±3.04)% (P<0.05), respectively, with no significant difference with that of NL group. The serum levels of TGF-ß and IFN-y on day 28 after infection were significantly different between N and NL groups (TGF-ß, 101.75±46.72 vs 260.90±45.34 pg/mL; IFN-y, 7.91±1.62 vs 14.11±3.72 pg/mL, both P<0.01). Similarly, significant difference was found for the plasma level of IL-10 on day 36 after infection between the S and N groups (41.85±3.14 vs 66.25±4.16 pg/mL, P<0.01), and between the SL and NL groups (44.48±3.87 vs 72.22±17.76 pg/mL, P<0.01), but not between the LPS groups and the control groups. CONCLUSION: LPS can induce the release of cytokines (e.g. TGF-ß) from B cells of mice infected with S. japonium, to facilitate the early development of adult female and male worms.


Assuntos
Linfócitos B/imunologia , Ativação Linfocitária , Schistosoma japonicum , Esquistossomose Japônica/imunologia , Animais , Linfócitos B/citologia , Citocinas/sangue , Feminino , Lipopolissacarídeos , Fígado/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos SCID , Baço/citologia , Linfócitos T/citologia
16.
Small ; 10(5): 855-8, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24745047

RESUMO

Nanotubes with different sizes can be readily assembled from simple DNA nanomotifs, which consist of just a few unique DNA sequences. Such structurally well-defi ned DNA-nanotubes will have great potential in many technological applications ranging from drug delivery, to determination of biomacromolecular 3D structures, to nanoplasmonic devices.


Assuntos
DNA/química , Nanotubos/química , Microscopia Crioeletrônica , Eletroforese em Gel de Poliacrilamida , Nanotubos/ultraestrutura , Conformação de Ácido Nucleico , Motivos de Nucleotídeos
17.
Exp Parasitol ; 136: 74-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24269199

RESUMO

In a previous study we demonstrated that CD4(+)CD25(+) regulatory T cells (Tregs) contributed to the escape of Schistosoma japonicum (S. japonicum) from the host's immune responses. In this paper, we studied the effect of cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) on CD4(+)CD25(+) Tregs in murine Schistosomiasis japonica and its corresponding role in the immune evasion of S. japonicum in mice. The results showed substantial reductions of worm burden and egg production in worm groups treated with anti-CD25 or anti-CTLA-4 monoclonal antibodies (mAb) compared to an infected but untreated control. The reduction effect was even enhanced in an experimental group co-treated with both mAbs. Compared to the control group, the percentage of CD4(+)CD25(+) Tregs was very much lower in the anti-CD25 mAb group as determined by FACS analyses and higher in the anti-CTLA-4 mAb group. ELISA analyses showed that both the anti-CTLA-4 mAb and the co-treated groups had higher levels of cytokines compared to the control group as well as larger egg granuloma sizes as determined by microscopical analyses of liver sections of infected mice. These results suggest that treatment with an anti-CTLA-4 mAb allows the host to clear S. japonicum, but at the cost of elevated pathological damage. The latter indicated a role of CTLA-4 in granuloma formation. Moreover, CD4(+)CD25(+) Tregs and CTLA-4 may exert synergistic effects during immune evasion processes by enhancing Th1-type immune response.


Assuntos
Antígeno CTLA-4/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Linfócitos T Reguladores/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Linfócitos T CD4-Positivos/imunologia , Citocinas/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Evasão da Resposta Imune , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Baço/citologia , Baço/imunologia
18.
Adv Mater ; : e2406135, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869350

RESUMO

Wide operation temperature is the crucial objective for an energy storage system that can be applied under harsh environmental conditions. For lithium-sulfur batteries, the "shuttle effect" of polysulfide intermediates will aggravate with the temperature increasing, while the reaction kinetics decreases sharply as the temperature decreasing. In particular, sulfur reaction mechanism at low temperatures seems to be quite different from that at room temperature. Here, through in situ Raman and electrochemical impedance spectroscopy studies, the newly emerged platform at cryogenic temperature corresponds to the reduction process of Li2S8 to Li2S4, which will be another rate-determining step of sulfur conversion reaction, in addition to the solid-phase conversion process of Li2S4 to Li2S2/Li2S at low temperatures. Porous bismuth vanadate (BiVO4) spheres are designed as sulfur host material, which achieve the rapid snap-transfer-catalytic process by shortening lithium-ion transport pathway and accelerating the targeted rate-determining steps. Such promoting effect greatly inhibits severe "shuttle effect" at high temperatures and simultaneously improves sulfur conversion efficiency in the cryogenic environment. The cell with the porous BiVO4 spheres as the host exhibits excellent rate capability and cycle performance under wide working temperatures.

19.
Exp Parasitol ; 135(1): 64-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23756146

RESUMO

Bone morphogenetic proteins (BMPs) are known to play an important role in the regulation of cell proliferation, survival, differentiation and apoptosis in many vertebrates and invertebrates through the TGF-ß signaling pathway. Although the TGF-ß signaling pathway exists in schistosomes, BMP homologue, a ligand of TGF-ß in Schistosoma japonicum, has not yet been identified. In this study, a BMP homologue of S. japonicum was cloned and characterized. The full length SjBMP cDNA is 3,020 bp and encodes 928 amino acids, which include a TGF-ß superfamily conserved domain at the C-terminus. BLAST analysis showed that, SjBMP has 68%, 51% and 43% homology with BMP from Schistosoma mansoni, Schmidtea mediterranea and Dugesia japonica at the amino acid level, respectively. According to data from real-time PCR, SjBMP was expressed in lung-stage schistosomula, 21-day liver-stage schistosomula, 50-day adult worms (the male and female), and eggs. The PCR data also indicated that, there was a ≈ 27- and ≈ 37-fold increase of SjBMP transcripts in the lung-stage schistosomula and eggs, respectively, and that there was relatively more SjBMP transcript in the adult male worm than in the adult female, in which the hepatic schistosomula was set as the calibrator for calculation. In situ hybridization based on FITC-labeled specific antisense oligonucleotide probes showed that SjBMP mRNA localized to the ovary of female worms and the integument and epithelium of female and male worms. After treatment with double-stranded RNA (dsRNA) at a concentration of 8 × 10(-2) µg/ml, which was added to the culture medium every other day for a week, the level of SjBMP mRNA in the cultured adult mixed-sex S. japonicum decreased at a range of ≈ 25-98% within 7 days compared with the level of SjBMP mRNA in the blank control group. On the 2nd day, the number of eggs produced per pair of worms decreased 28.7%, and the percent of normal eggs also decreased (12.7% vs. 4.3%) in the SjBMP dsRNA-treated group when compared with the eggs laid by the blank control group. No difference was detected between the two groups on the 7th day of treatment, because the eggs of the untreated worms were also mostly abnormal, similar to the eggs laid by the treated group. In addition, no significant difference in the morphological structure of the adult worms was observed. Thus, the preliminary in vitro experiment indicated that SjBMP may be involved in the oviposition behavior of S. japonicum, and further studies based on the recombinant virus vector-induced steady knockdown of SjBMP or in vivo experiments are required for more in-depth investigation.


Assuntos
Proteínas Morfogenéticas Ósseas/isolamento & purificação , Schistosoma japonicum/química , Sequência de Aminoácidos , Animais , Proteínas Morfogenéticas Ósseas/química , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Feminino , Soros Imunes/metabolismo , Hibridização in Situ Fluorescente , Ponto Isoelétrico , Masculino , Camundongos , Filogenia , RNA de Helmintos/genética , RNA de Helmintos/isolamento & purificação , RNA Mensageiro/análise , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Schistosoma japonicum/classificação , Schistosoma japonicum/genética , Alinhamento de Sequência , Caramujos
20.
Parasitol Res ; 112(4): 1483-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23354940

RESUMO

Schistosomiasis japonica remains one important public health concern that cause great loss of humans' health and social-economic development in the Peoples' Republic of China. At the end of 1990s and the beginning of 2000s, there were still about 0.8 million patients and nearly 85 million people living in the epidemic areas around China. We undertook full analysis of the epidemiological data of schistosomiasis taken from the report of schistosomiasis status in People's Republic of China from 1999 to 2010 for effectiveness assessment of China's new strategy for schistosomiasis control nationwide after its implementation since the beginning the 21st century. The schistosomiasis-endemic uncontrolled counties or towns decreased in number from 1,149 in 2002 to 643 in 2010 at a rate of 44%. The number of schistosomiasis patients decreased from nearly 800,000 to less than 326,000 in 2010 at a decrease rate of more than 50%. The number of acute schistosomiasis patients also decreased significantly, and only 43 cases were reported in 2010. The infection rates of cattle in the endemic uncontrolled provinces decreased greatly though the number of cattle and the actual snail habitat areas remained large with no obvious decline. The schistosome infection rates of human and cattle both decreased significantly by more than 64% and 75%. However, most of the uncontrolled schistosomiasis-endemic areas, schistosomiasis patients, and acute cases are generally located in the four provinces (Hunan, Hubei, Jiangxi, and Anhui) of the lake regions in the middle and lower reach of the Yangtze River, and the egg-positive rates in diagnosed human in endemic Hunan and Hubei remained higher than 10%. Therefore, the new strategy of schistosomiasis control via integrated measures emphasizing infection source control is scientific and successful around China, though it is essential to explore an effective and sustainable strategy for schistosomiasis control in the tough lake and marshland regions of China. The four provinces (Hunan, Hubei, Jiangxi, and Anhui) of the lake regions in China are the main battlefield of China's schistosomiasis control in the present and future.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Controle de Doenças Transmissíveis/métodos , Esquistossomose/epidemiologia , Esquistossomose/veterinária , Animais , Bovinos , Doenças dos Bovinos/parasitologia , China/epidemiologia , Política de Saúde , Pesquisa sobre Serviços de Saúde , Humanos , Incidência , Prevalência , Esquistossomose/prevenção & controle
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