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1.
J Am Chem Soc ; 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32881493

RESUMO

The potential applications of metal-organic cages (MOCs) are mostly achieved through specific host-guest interactions within their cavities. Electronic applications would require an effective electron transport pathway, which has been extensively studied in hybrid organic-inorganic materials with extended structures. These properties have not been considered for MOCs because cage-to-cage interactions in these materials have rarely been examined and are challenging to functionalize. We report here a previously unobserved actinide-based MOC assembled from four hexagonal-bipyramidal-coordinated uranyl ions and six bidentate flexible ligands. Remarkably, each isolated cage is further interlocked with six adjacent ones through mechanical bonds, resulting in the first case of a 0D → 3D f-element polycatenated metal-organic cage, SCU-14. Long-range π-π stacking extending throughout the structure is built via polycatenation, providing a visible carrier transmission path. SCU-14 is also an extremely rare case of an intrinsically semiconductive MOC with a wide band gap of 2.61 eV. Combined with the high X-ray attenuation efficiency, SCU-14 can effectively convert X-ray photons to electrical current signals and presents a promising sensitivity of 54.93 µC Gy-1 cm-2.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32880437

RESUMO

Uncontrollable growth of Lithium (Li) dendrite has severely hindered the development of Li metal anodes, while separator modification is regarded as a simple and effective way to mitigate the growth of Li dendrite. However, the "drop-dregs" phenomenon of coating layer desquamated from polyolefin separator due to their different Young's modulus would induce non-uniform Li ionic flux, finally resulting in deteriorative electrochemical performance and even thermal runaway of the battery. Herein, we introduce a novel nanopile mechanical interlocking strategy to create delamination-free separator modification, that could stably generate homogeneous Li ionic flux to guide long-term uniform Li deposition. Both experimental and simulation results demonstrate strong bonding strength between coating layer and membrane matrix based on this physical interlocking mechanism. Consequently, with nearly dendrite-free Li deposition and largely reduced interface impedance, 1000 h stable cycling of Li//Li half cells enrolled this modified separator is successfully achieved. And a significantly improvement of Li/LiFePO4 full cells in long-term cycling stability to 500 cycles further indicates its promising practical potential. Moreover, this presented approach without any binding agents or surface activation procedures could be facilely scaled up, providing an applicable and durable separator modification solution towards stable Li metal anodes.

3.
Membranes (Basel) ; 10(5)2020 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357523

RESUMO

The treatment of cancer has evolved significantly in recent years with a strong focus on immunotherapy. Encapsulated Cell Therapy (ECT) for immunotherapy-based anti-cancer treatment is a unique niche within this landscape, where molecules such as signaling factors and antibodies produced from cells are encapsulated within a vehicle, with a host amount of benefits in terms of treatment efficacy and reduced side effects. However, traditional ECTs generally lie in two extremes; either a macro scale vehicle is utilized, resulting in a retrievable system but with limited diffusion and surface area, or a micro scale vehicle is utilized, resulting in a system that has excellent diffusion and surface area but is unretrievable in the event of side effects occurring, which greatly compromises the biosafety of patients. In this study we adapted our patented and novel electrospun Polysulfone (PSF) Microtube Array Membranes (MTAMs) as a 'middle' approach to the above dilemma, which possess excellent diffusion and surface area while being retrievable. Hybridoma cells were encapsulated within the PSF MTAMs, where they produced CEACAM6 antibodies to be used in the suppression of cancer cell line A549, MDA-MB-468 and PC 3 (control). In vitro and in vivo studies revealed excellent cell viability of hybridoma cells with continuous secretion of CEACAM6 antibodies which suppressed the MDA-MB-468 throughout the entire 21 days of experiment. Such outcome suggested that the PSF MTAMs were not only an excellent three-dimensional (3D) cell culture substrate but potentially also an excellent vehicle for the application in ECT systems. Future research needs to include a long term in vivo >6 months study before it can be used in clinical applications.

4.
Adv Mater ; 32(23): e1908027, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32350944

RESUMO

Currently, exploring high-volumetric-capacity electrode materials that allow for reversible (de-)insertion of large-size K+ ions remains challenging. Tellurium (Te) is a promising alternative electrode for storage of K+ ions due to its high volumetric capacity, confirmed in lithium-/sodium-ion batteries, and the intrinsic good electronic conductivity. However, the charge storage capability and mechanism of Te in potassium-ion batteries (KIBs) have not been unveiled until now. Here, a novel K-Te battery is constructed, and the K+ -ion storage mechanism of Te is revealed to be a two-electron conversion-type reaction of 2K + Te ↔ K2 Te, resulting in a high theoretical volumetric capacity of 2619 mAh cm-3 . Consequently, the rationally fabricated tellurium/porous carbon electrodes deliver an ultrahigh reversible volumetric capacity of 2493.13 mAh cm-3 at 0.5 C (based on Te), a high-rate capacity of 783.13 mAh cm-3 at 15 C, and superior long-term cycling stability for 1000 cycles at 5 C. This excellent electrochemical performance proves the feasibility of utilizing Te as a high-volumetric-capacity active material for storage of K+ ions and will advance the practical application of KIBs.

5.
J Biomed Mater Res B Appl Biomater ; 108(7): 2903-2911, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32374516

RESUMO

Sepsis is a deadly disease that is widely attributed to endotoxin released by gram-negative bacterial infections often plague emergency care facilities. Conventionally antibiotics and vasopressors are used to treat this disease. Recent treatment protocol shifted to a membrane to remove the offending endotoxin monomer. Despite this shift, membrane-based devices are often extremely costly, hindering accessibility to this life saving medical device. In view of this challenges, we adopted the internally developed polysulfone (PSF) microtube array membrane alternating (MTAM-A) for use in blood sepsis treatment. PSF MTAM-A were with polymyxin B (PMB) molecules immobilized were assembled into an internally developed cartridge housing and subjected to endotoxin removal models with water and blood spiked with 100 EU/ml of endotoxin as the feed solution. Samples were derived at 15, 30, 60, and 120 min and endotoxin levels were determined with limulus amebocyte lysate assay and benchmarked against the commercially available Toraymyxin device. The PSF MTAM-A with 2.3 times the surface area was successfully fabricated and with PMB molecules immobilized, and assembled into a hemoperfusion device. Dynamic endotoxin removal test revealed and overall endotoxin removal capacity of 90% and a superior endotoxin removal efficiency that was significantly higher than that of Toraymyxin (internally conducted and reported). The data suggested that PSF MTAM-A PMB membranes could potentially be applied in future hemoperfusion devices which would be significantly more efficient, compact, and affordable; potentially making such a life-saving medical device widely available to the general public.

6.
Angew Chem Int Ed Engl ; 59(29): 11856-11860, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32270587

RESUMO

Semiconductive metal-organic frameworks (MOFs) have emerged in applications such as chemical sensors, electrocatalysts, energy storage materials, and electronic devices. However, examples of semiconductive MOFs within flexible electronics have not been reported. We present flexible X-ray detectors prepared by thermoplastic dispersal of a semiconductive MOF (SCU-13) through a commercially available polymer, poly(vinylidene fluoride). The flexible detectors exhibit efficient X-ray-to-electric current conversion with enhanced charge-carrier mobility and low trap density compared to pelleted devices. A high X-ray detection sensitivity of 65.86 µCGyair -1 cm-2 was achieved, which outperforms other pelleted devices and commercial flexible X-ray detectors. We demonstrate that the MOF-based flexible detectors can be operated at multiple bending angles without a deterioration in detection performance. As a proof-of-concept, an X-ray phase contrast under bending conditions was constructed using a 5×5 pixelated MOF-based imager.

7.
Chem Asian J ; 15(8): 1290-1295, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32166912

RESUMO

Organic electrode materials hold great potential for fabricating sustainable energy storage systems, however, the development of organic redox-active moieties for rechargeable aqueous zinc-ion batteries is still at an early stage. Here, we report a bio-inspired riboflavin-based aqueous zinc-ion battery utilizing an isoalloxazine ring as the redox center for the first time. This battery exhibits a high capacity of 145.5 mAh g-1 at 0.01 A g-1 and a long-life stability of 3000 cycles at 5 A g-1 . We demonstrate that isoalloxazine moieties are active centers for reversible zinc-ion storage by using optical and photoelectron spectroscopies as well as theoretical calculations. Through molecule-structure tailoring of riboflavin, the obtained alloxazine and lumazine molecules exhibit much higher theoretical capacities of 250.3 and 326.6 mAh g-1 , respectively. Our work offers an effective redox-active moiety for aqueous zinc batteries and will enrich the valuable material pool for electrode design.

8.
ACS Appl Mater Interfaces ; 12(3): 3681-3687, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31891243

RESUMO

The development of lithium metal anodes has been severely impeded by the detrimental lithium (Li) dendrite growth which can largely shorten the lifespan of the battery. Here, we propose a one-step redox strategy to fabricate reduced graphene oxide (rGO) and Cu2O co-modified Cu current collector (rGO-Cu2O/Cu), which can guide the uniform Li ion nucleation and suppress the formation of the Li dendrite. The lithiophilic Cu2O in situ grown on the Cu substrate via direct chemical oxidation of Cu foil by the GO solution can decrease the Li nucleation overpotential and regulate the preferential nucleation of Li ions, while the rGO produced at the same time can facilitate the electron transport. As the consequence of the synergistic effects, rGO-Cu2O/Cu could be fully discharged with largely enhanced Coulombic efficiency of 98% and extended cycling life of the symmetrical cell up to 300 h. The full battery assembled with LiFePO4 also exhibits satisfying electrochemical performance, indicating the promising practical application of this Li-plated rGO-Cu2O/Cu anode. Furthermore, the processable rGO-Cu2O/Cu which can make Li metal anode moldable into various shapes with a controllable size will be favorable to manufacture diverse device architectures.

9.
Nanoscale ; 12(1): 79-84, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31825064

RESUMO

Recently, dual-ion batteries (DIBs) have received immense attention owing to their high operating voltage and low cost, and further studies on the enhancement of their energy densities and cyclabilities are being intensively pursued. Herein, a novel Ge-based DIB has been developed for the first time by using a rationally designed nanocomposite of Ge particles embedded in one-dimensional carbon nanofibers (Ge/CNFs) as an anode. The resulting battery shows a high discharge capacity of 281 mA h g-1 at a discharge current of 0.25 A g-1 and a superb rate capability of 94 mA h g-1 at a discharge current of 2.5 A g-1, which greatly surpasses those of most of the reported DIBs. These remarkable properties can be ascribed to the fact that the uniform one-dimensional nanostructure facilitates the improvement of lithium-ion diffusion within the hybrids, and the carbon matrix effectively alleviates the volume expansion of Ge during the cycling process and simultaneously enhances the electrical conductivity of the hybrids. The charge storage mechanism of Ge/CNFs is found to be Ge alloying with Li, accompanied by a phase transformation process from crystalline Ge to amorphous LixGe alloys. This work paves the way for the rational utilization of Ge-based materials in new-generation high-performance DIBs.

10.
Dalton Trans ; 48(46): 17331-17339, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31724671

RESUMO

Using two Schiff-base ligands containing an electron-withdrawing group (NO2), we obtained two mononuclear and two trinuclear complexes with the general formula [Dy(hni)(NO3)(DMF)2]·DMF (1·DMF), [Dy(hni)2(H2O)2]·NO3·EtOH (2·NO3·EtOH), [Dy3(hnc)3(DMF)6] (3) and [Gd3(hnc)3(DMF)6] (4) (H-hni: 2-(hydroxyl-3-methoxy-5-nitrophenyl)methylene(isonictino)hydrazine and H3-hnc: 1,5-bis(2-hydroxy-3-methoxy-5-nitrobenzylidene)carbonohydrazide). Four complexes were confirmed by infrared spectroscopy and single-crystal X-ray diffraction. The crystal structure of complex 3 reveals that the modified Schiff-base ligand provides two different tridentate coordination pockets (ONN and ONO) to encapsulate DyIII with a unique N-N pathway. The magnetic properties of all four complexes have been investigated using dc and ac susceptibility measurements. The frequency-dependent ac susceptibility is indicative of single-molecule magnetic behavior without and/or with an optimum dc field with a relaxation barrier Ueff = 34 K (400 Oe), 19 K (0 Oe) and 80 K (0 Oe) for complexes 1, 2 and 3, respectively.

11.
Dalton Trans ; 48(48): 17858-17863, 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31777910

RESUMO

Efficient removal of radioactive 90Sr from nuclear waste solutions and natural water systems is of vital importance due to its radioactive nature and high mobility. We present here an anionic layered compound (NC4H12)(NC2H8)2[In3(pydc)6]·13.1H2O (SZ-6; pydc = 2,5-pyridinedicarboxylic acid) with the potential remediation ability towards radioactive Sr2+ from seawater. This material exhibits excellent ß and γ radiation resistance both in air and in aqueous solutions. Besides, this material could maintain its structural integrity in real seawater for 77 days. The adsorption experiment results show that SZ-6 exhibits superior Sr2+ removal capability over a wide pH range from 4 to 12 with fast adsorption kinetics and high selectivity. The effective removal of 90Sr from real seawater was demonstrated as well. Our results strongly suggest the potential application of SZ-6 for selectively capturing radionuclides in natural water systems.

12.
ACS Appl Mater Interfaces ; 11(49): 45755-45762, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31729853

RESUMO

Recently, dual-ion batteries (DIBs) are regarded as a promising alternative to well-developed lithium-ion batteries, and the development of high-performance and abundant-sodium-based DIBs (SDIBs) is being intensively pursued. In this work, a novel SDIB composed of a phosphorus (P)-based anode and graphite (G) cathode is successfully constructed for the first time. This P-G SDIB shows a high working voltage of around 3.9 V, a high reversible capacity of 373 mA h/g, good rate capability, and long cyclability, which are superior to those of the most reported DIBs. The ex situ X-ray diffraction, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy tests reveal the insertion/extraction mechanism of Na+ ions into/from P-based anodes via reversible Na-P alloying reactions accompanied with high charge-storage capability. Moreover, the presodiation of P-based composites is found to be an efficient approach to boost the cycling performance of the P-G SDIB by forming a stable NaF-rich solid electrolyte interphase layer to alleviate electrolyte decomposition. Our results demonstrate that P-based SDIBs possess tremendous potential for practical electrochemical energy-storage applications.

13.
Angew Chem Int Ed Engl ; 58(46): 16451-16455, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31482655

RESUMO

Alloying anodes are promising high-capacity electrode materials for K-ion batteries (KIBs). However, KIBs based on alloying anodes suffer from rapid capacity decay due to the instability of K metal and large volume expansion of alloying anodes. Herein, the effects of salts and solvents on the cycling stability of KIBs based on a typical alloying anode such as amorphous red phosphorus (RP) are investigated, and the potassium bis(fluorosulfonyl)imide (KFSI) salt-based carbonate electrolyte is versatile to achieve simultaneous stabilization of K metal and RP electrodes for highly stable KIBs. This salt-solvent complex with a moderate solvation energy can alleviate side reactions between K metal and the electrolyte and facilitate K+ ion diffusion/desolvation. Moreover, robust SEI layers that form on K metal and RP electrodes can suppress K dendrite growth and resist RP volume change. This strategy of electrolyte regulation can be applicable to other alloying anodes for high-performance KIBs.

14.
Dalton Trans ; 48(15): 4823-4829, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30724286

RESUMO

Expanding the family of f-element bearing molybdate iodates via hydrothermal reactions has yielded ten new rare-earth molybdate iodates with two distinct phases, Ln(MoO2)(IO3)4(OH) (LnMoIO-1, Ln = Ce and Pr) and Ln(Mo2O7)(IO3)(H2O)2 (LnMoIO-2, Ln = Gd-Yb, and Y), as well as the first thorium molybdate iodate, ThF(MO4)(IO3) (ThFMoIO). All three structures exhibit three dimensional frameworks and are exclusively built from lanthanide/actinide polyhedra bridged by molybdates and iodates. Furthermore, the coordination versatility of molybdates (octahedral, square pyramidal, and tetrahedral geometries) results in a diversity of structures. The effect of the lanthanide contraction on the compositions and structures is clearly observed, showing the increase in hydration from the early to late lanthanide analogues and the decrease in unit cell dimensions and the average Ln-O bonding distances across the same structure type. Single crystal X-ray diffraction studies reveal that LnMoIO-1 (Ln = Ce and Pr) crystalize in a noncentrosymmetric space group P21 and the second-harmonic generation (SHG) measurement shows a response of 5 × KDP for PrMoIO-1. In addition, CeMoIO-1 crystallizes as orange coloured tablets which are semiconducting in nature with a band gap of 2.41 eV.

15.
Medicine (Baltimore) ; 97(23): e10891, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29879024

RESUMO

The aim of this study was to evaluate the relationship between interleukin-21 (IL-21) and interleukin-21 receptor (IL-21R) polymorphisms and the response to peginterferon alfa (PEG-IFN α) therapy in HBeAg-positive chronic hepatitis B (CHB) patients.A total of 143 HBeAg-positive CHB patients treated for 48 weeks with PEG-IFN α and followed up for 24 weeks post-treatment were retrospectively evaluated. Genotypes analysis was performed for IL-21 polymorphisms rs907715, rs2221903, and IL-21R polymorphisms rs3093301 and rs2285452. Serum IL-21 levels were measured by enzyme-linked immunosorbent assay.The end of virological response (EVR) rate was 46.9% (67/143) at the end of treatment, the sustained virological response (SVR) rate was 43.4% (62/143) and the complete response (CR) rate was 32.1% (46/143) at 24 weeks post-treatment. Patients who carried IL-21 rs 2221903 genotype AA had a rather higher rate of EVR (response rate: 52.4%, odds ratio [OR] 0.42, 95% confidence interval [CI]: 0.19-0.91, P = .021), SVR (response rate: 47.6%, OR 0.43, 95% CI: 0.19-0.95, P = .028), and CR (response rate: 38.1%, OR 0.31, 95% CI: 0.12-0.79, P = .014) when compared to those had AG genotype. Meanwhile, IL-21rs 2221903 genotype AA was also independently associated with markedly reduced HBsAg levels (>1og10 IU/mL) after 24 weeks treatment and low HBsAg levels (<100 IU/mL) at the end of treatment. IL-21 rs907715 AG/GG genotype was independently associated with SVR (OR: 2.92, 95% CI: 0.98-8.6, P = .039; OR: 3.23, 95% CI: 1.0-10.4, P = .039). Patients with IL-21 rs907715 AG/GG genotype had higher serum IL-21 levels than those with rs907715 AA genotype (P = .021).IL-21 rs2221903 and rs907715 polymorphisms were significantly associated with the treatment response to PEG-IFN α among Chinese HBeAg-positive CHB patients.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Interleucinas/genética , Receptores de Interleucina-21/genética , Adulto , Grupo com Ancestrais do Continente Asiático , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B , Hepatite B Crônica/genética , Humanos , Interleucinas/sangue , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Resposta Viral Sustentada , Resultado do Tratamento , Adulto Jovem
16.
ACS Appl Mater Interfaces ; 9(25): 21298-21306, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28594545

RESUMO

Currently, the energy crisis and environmental pollution are two critical challenges confronted by humans. The development of smart strategies to address the above-mentioned issues simultaneously is significant. As the main accomplices for water pollution, several kinds of organic dyes with intrinsic redox functional groups such as phenothiazines derivatives, anthraquinone, and indigoid dyes are potential candidates for the replacement of the conventional pseudocapacitive materials. In this work, three typical organic dyes can be efficiently removed by a facile adsorption procedure using reduced graphene oxide coated cellulose fiber (rGO@CF) paper. Flexible supercapacitors based on dye/rGO@CF electrodes exhibit excellent electrochemical performances that are superior to or comparable with those of conventional pseudocapacitive materials based devices, presenting a new type of promising electrode materials. Moreover, benefiting from the high flexibility and considerable mechanical strength of the graphene composite paper, the operating potential and capacitance of the devices can be easily adjusted by tailoring the hybrid electrodes into different specific shapes followed by rational integrating. The smart design of these dye/rGO@CF paper based electrodes shows that energy storage and environmental remediation can be achieved simultaneously.

17.
Org Biomol Chem ; 13(7): 2100-7, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25525831

RESUMO

A straightforward synthesis of novel, 2-heterocyclyl polyhydroxylated pyrrolidines is described. Stereocontrolled additions of nucleophiles to cyclic nitrones generated the corresponding 2,3-trans adducts, allowing the synthesis of the corresponding pyrrolidines via key intermediates bearing an alkyne and a nitrile oxide. Three hybrid systems, including a pyrrolidine with two isoxazoles and one triazole, are efficiently prepared via 1,3-dipolar cycloaddition. Biological testing of the product alkaloids showed that subtle structural variations have drastic effects on their inhibitory activities against glucosidases.

18.
Anal Chem ; 86(11): 5567-72, 2014 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24819867

RESUMO

Rapid and efficient detection of cancer cells at their earliest stages is one of the central challenges in cancer diagnostics. We developed a simple, cost-effective, and highly sensitive colorimetric method for visually detecting rare cancer cells based on cell-triggered cyclic enzymatic signal amplification (CTCESA). In the absence of target cells, hairpin aptamer probes (HAPs) and linker DNAs stably coexist in solution, and the linker DNA assembles DNA-AuNPs, producing a purple solution. In the presence of target cells, the specific binding of HAPs to the target cells triggers a conformational switch that results in linker DNA hybridization and cleavage by nicking endonuclease-strand scission cycles. Consequently, the cleaved fragments of linker DNA can no longer assemble into DNA-AuNPs, resulting in a red color. UV-vis spectrometry and photograph analyses demonstrated that this CTCESA-based method exhibited selective and sensitive colorimetric responses to the presence of target CCRF-CEM cells, which could be detected by the naked eye. The linear response for CCRF-CEM cells in a concentration range from 10(2) to 10(4) cells was obtained with a detection limit of 40 cells, which is approximately 20 times lower than the detection limit of normal AuNP-based methods without amplification. Given the high specificity and sensitivity of CTCESA, this colorimetric method provides a sensitive, label-free, and cost-effective approach for early cancer diagnosis and point-to-care applications.


Assuntos
Técnicas Biossensoriais/métodos , Células/química , Neoplasias/química , Técnica de Seleção de Aptâmeros/métodos , Adenosina Trifosfatases/química , Animais , Aptâmeros de Nucleotídeos/química , Linhagem Celular Tumoral , Colorimetria , DNA/química , Ouro/química , Humanos , Nanopartículas Metálicas , Camundongos , Espectrofotometria Ultravioleta
19.
Talanta ; 115: 823-9, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054669

RESUMO

Multifunctional fluorescent silica nanoparticles with phenylboronic acid tags were developed for labeling sialic acid on the surface of living cancer cells. In this paper, fluorescent silica nanoparticles (FSNPs) with strong and stable emission at 515 nm were firstly prepared through a reverse microemulsion process, and then modified with highly selective phenylboronic acid (PBA) tags on their surface via an aqueous 'thiol-ene' click reaction. These nanoparticles had a hydrodynamic diameter of 92.6 ± 9.1 nm, and a bright fluorescence signal, which is 366 times higher than that of a single dye molecule. Meanwhile, these PBA-tagged FSNPs were found very stable in aqueous solution as well as in cell culture medium, verified by transmission electron microscopy, X-ray photoelectron spectroscopy and zeta potential analysis. The over-expressed sialic acid (SA) on the membrane of living HeLa cells was visualized in situ by a confocal laser scanning microscopy, ascribed to the specific interaction between PBA and SA. Thus, the PBA-FSBPs showed a great potential in probing SA expressed on living cells with high selectivity and sensitivity.


Assuntos
Ácidos Borônicos/química , Imagem Molecular/métodos , Nanopartículas/química , Ácidos Siálicos/química , Dióxido de Silício/química , Compostos de Sulfidrila/química , Química Click , Corantes Fluorescentes , Células HeLa , Humanos , Microscopia Confocal , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Sensibilidade e Especificidade
20.
BMC Public Health ; 13: 713, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23915378

RESUMO

BACKGROUND: Chronic non-communicable diseases have become the major cause of death in China. This study describes and compares chronic disease mortality between urban and rural residents in Hubei Province, central China. METHODS: Death records of all individuals aged 15 years and over who died from 2008 through 2010 in Hubei were obtained from the Disease Surveillance Points system maintained by the Hubei Province Centers for Disease Control and Prevention. Average annual mortality, standardized death rates, years of potential life lost (YLL), average years of potential life lost (AYLL) and rates of life lost were calculated for urban and rural residents. Standardized rate ratios (SRR) were calculated to compare the death rates between urban and rural areas. RESULTS: A total of 86.2% of deaths were attributed to chronic non-communicable diseases in Hubei. Cerebrovascular diseases, ischemic heart disease and neoplasms were the main leading causes in both urban and rural areas, and the mortality rates were higher among rural residents. Lung cancer was the principal cause of mortality from cancer among urban and rural residents, and stomach cancer and liver cancer were more common in rural than urban areas. Breast cancer mortality among women in rural areas was lower than in urban areas (SRR=0.73, 95% CI=0.63-0.85). The standardized mortality for chronic lower respiratory disease among men in rural areas was higher than in urban areas (SRR=4.05, 95% CI=3.82-4.29). Among men, total AYLL from liver cancer and other diseases of liver were remarkably higher than other causes in urban and rural areas. Among women the highest AYLL were due to breast cancer in both urban and rural areas. CONCLUSIONS: Chronic diseases were the major cause of death in Hubei Province. While circulatory system diseases were the leading causes in both urban and rural areas, our study highlights that attention should also be paid to breast cancer among women and chronic lower respiratory disease among rural residents. It is important that governments focus on this public health issue and develop preventive strategies to reduce morbidity and premature mortality from chronic non-communicable diseases.


Assuntos
Doença Crônica/mortalidade , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , China/epidemiologia , Feminino , Humanos , Expectativa de Vida , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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