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1.
Inorg Chem ; 63(4): 1879-1887, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38240218

RESUMO

The development of efficient fluorescent probes and adsorbents for detecting and removing Cu2+, which pose potential environmental and health risks, is a highly active area of research. However, achieving simultaneously improved fluorescence detection efficiency and enhanced adsorption capacity in a single porous probe remains a significant challenge. In this study, we successfully synthesized a two-dimensional imine-based TAP-COF using 2,4,6-triformylphloroglucinol and tri(4-aminophenyl)amine as raw materials. TAP-COF exhibited excellent properties, including a large specific surface area of 685.65 m2·g-1, exceptional thermal stability (>440 °C), chemical stability, temporal stability, and recyclability. Fluorescence testing revealed that TAP-COF exhibited remarkable specificity and high sensitivity for detecting Cu2+. The fluorescence mechanism, in which the excited state intramolecular proton transfer was impeded by the interaction of Cu2+ with C═O and C-N bonds on TAP-COF upon the addition of Cu2+, was further elucidated through experimental and theoretical methods. Furthermore, the adsorption capacity of TAP-COF toward Cu2+ was investigated, confirming the excellence of TAP-COF as a fluorescent probe and adsorbent for the specific detection and removal of Cu2+. This work holds significant implications for improving environmental and human health concerns associated with Cu2+ contamination.

2.
Inorg Chem ; 62(16): 6288-6296, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37036292

RESUMO

The reactivity of two α-diimine-ligated digallanes, [L2-Ga-GaL2-] (La = [(2,6-iPr2C6H3)NC(CH3)]2, dpp-dad, 1; Lb = 1,2-[(2,6-iPr2C6H3)NC]2C10H6, dpp-bian, 2), and a gallylene, [(La)2-GaNa(THF)3] (3), toward organic azides was studied. Reaction of digallane 1 or 2 with trimethylsilyl azide (Me3SiN3), 2-azido-benzonitrile (2-CNC6H4N3), or tosylazide (TosN3) results in imido-bridged complexes, [(La)·-Ga(µ-NSiMe3)2Ga(La)·-] (4) [(Lb)·-Ga(µ-NSiMe3)2Ga(Lb)·-] (5), [(Lb)·-Ga(µ-2-CNC6H4N)2Ga(Lb)·-] (6), and [(Lb)·-Ga(µ-NTos)2Ga(Lb)·-] (7), with elimination of dinitrogen. Treatment of 1 or 2 with 1-adamantyl azide (1-AdN3), on the other hand, affords the unsymmetrical dinuclear complexes [(La)·-Ga(NAd)(N3Ad)Ga(La)·-] (8) and [(Lb)·-Ga(NAd)(N3Ad)Ga(Lb)·-] (9), which contain both imido and triazene bridges. Different from the Ga(II) complexes 1 and 2, the reactions of Ga(I) species 3 with benzylazide or trimethylsilyl azide result in the tetrazene complex {Na(THF)}2[(La)2-Ga(benzyl-N4-benzyl)]2 (10) and amide complex {Na(THF)4}[(La)2-Ga(NHSiMe3)(benzyl)] (11). It is likely that these latter transformations proceed via the transient formation of the corresponding Ga═N imide complex, which undergoes either cycloaddition with a second azide (to form 10) or activation of the C-H bond of methyl in one solvent toluene molecule (to yield 11).

3.
Macromol Rapid Commun ; 44(15): e2300128, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37139707

RESUMO

Regenerative medicine is a highly regarded multidisciplinary field that aims to transform the future of clinical medicine through curative strategies rather than palliative therapies. As an emerging field, the development of regenerative medicine cannot be achieved without multifunctional biomaterials. Among the various bioscaffold materials, hydrogels are one of the materials of interest in bioengineering and medical research because of their similarity to the natural extracellular matrix and good biocompatibility. However, conventional hydrogels have simple internal structures and single cross-linking modes, which require improvement in a single function and structural stability. Introducing multifunctional nanomaterials into 3D hydrogel networks physically or chemically avoids their disadvantages. Nanomaterials (NMs) are materials in the size range of 1-100 nm with distinct physical and chemical properties that differ from that of the macroscopic size and enable hydrogels to exhibit multifunctionality. Although regenerative medicine and hydrogels have been well researched in their respective fields, the connection between nanocomposite hydrogels (NCHs) and regenerative medicine has not been elaborated. Therefore, this review briefly describes the preparation and design requirements of NCHs and discusses their applications and challenges in regenerative medicine, hoping to clarify the relationship between the two.


Assuntos
Medicina Regenerativa , Engenharia Tecidual , Nanogéis , Materiais Biocompatíveis/uso terapêutico , Hidrogéis/química
4.
J Chem Phys ; 159(8)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37610018

RESUMO

Developing dyes with high open-circuit photovoltage (Voc) is a vital strategy to improve the power conversion efficiency (PCE) of co-sensitized solar cells (co-DSSCs). Herein, three organic fluorine-containing dyes [YY-ThP(3F), YY-ThP(2F), and YY-ThP(26F)] are designed and synthesized for investigating the fluorine-induced effect on photophysical and photovoltaic performances. Consequently, this effect can significantly broaden the UV-vis absorption spectra of dyes but fail to improve the light-harvesting capability of DSSCs. Strikingly, YY-ThP(3F), featuring 3-position fluorine substitution to cyanoacrylic acid, yields a relatively high Voc compared to the corresponding fluorine-free dye (YY-ThP). Furthermore, the co-sensitization of YY-ThP+YY-ThP(3F) achieves a remarkably high PCE and long-term stability. This work implies that the combination of judicious molecular engineering and co-sensitization is a promising strategy for highly efficient and stable DSSCs.

5.
Cell Biol Int ; 46(5): 840-848, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35143103

RESUMO

Although many previous studies have found that the mitotic arrest deficient 2-like 1 (MAD2L1) protein contributes to the proliferation of colorectal cancer (CRC) cells, but the upstream mechanism of MAD2L1 is still largely elusive. This study aimed to explore the microRNAs (miRNAs) upstream of MAD2L1 to improve our understanding of the mechanism of the MAD2L1 gene in CRC. The upstream target miRNAs (miR-515-5p) of MAD2L1 were predicted by the online databases miRWalk, miRDIP, and TargetScan. Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of miR-515-5p in human CRC tissues. The targeting relationship between miR-515-5p and MAD2L1 was tested by dual luciferase reporter gene assays. The effects of miR-515-5p on the biological behaviors of CRC cells by regulating MAD2L1 expression were verified by qRT-PCR, western blot, Cell Counting Kit-8, and flow cytometry. The results showed that miR-515-5p was a highly reliable upstream miRNA of the MAD2L1 gene. As an upstream target miRNA of MAD2L1, miR-515-5p was lowly expression in CRC tissues. The overexpression of miR-515-5p could inhibit the proliferation of CRC cells and induce cell cycle arrest at the G1 phase leading to cell apoptosis. However, MAD2L1 gene overexpression could reverse the effects of miR-515-5p overexpression on the biological behaviors of CRC cells above. This study illustrated that miR-515-5p can inhibit proliferation and induce G1 phase arrest leading to apoptosis in CRC cells. The mechanism underlying this phenomenon may be related to the negative targeted regulation of MAD2L1.


Assuntos
Neoplasias Colorretais , MicroRNAs , Apoptose/genética , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Mad2/genética , Proteínas Mad2/metabolismo , Proteínas Mad2/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo
6.
Inorg Chem ; 61(3): 1787-1796, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34991312

RESUMO

High-performance microwave-absorbing materials (MAMs) derived from metal-organic frameworks (MOFs) have attracted considerable attention due to their tunable chemical composition and microstructure. In this contribution, a core-shell-structured Co/MnO/C nanocomplex was prepared using a CoMn-MIL MOF by a facile hydrothermal synthesis and subsequent pyrolysis process. The optimal microwave absorption (MA) property of the as-prepared Co/MnO/C nanocomplex was achieved by the regulation of the Co2+/Mn2+ molar ratio. The minimum reflection loss (RLmin) of the Co/MnO/C-31 nanocomplex was low to -55.0 dB at 16.2 GHz with a thickness of 1.49 mm, and the effective absorption bandwidth (EAB) was high to 5.95 GHz (12.05-18 GHz) at a thickness of 1.8 mm. The mixed-metal nanocomplex with the core-shell structure exhibited outstanding MA performance, corresponding to the synergetic effect of the magnetic and dielectric loss. It provides a high efficiency strategy for rendering low reflection loss and broad EAB to high-performance MAMs.

7.
Anal Bioanal Chem ; 414(19): 5887-5897, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35676562

RESUMO

Hypochlorous acid (HClO), the core bactericidal substance of the human immune system, plays a vital role in many physiological and pathological processes in the human body. In this work, we designed and synthesized a novel deep-red fluorescent probe TCF-ClO for the determination of hypochlorous acid through theoretical analysis. The results showed that probe TCF-ClO exhibited excellent characteristics of long-wavelength emission (635 nm), fast response (< 1 min), and low detection limit (24 nM). In addition, it had been successfully used for imaging of HClO in living HeLa cells. More importantly, the TCF-ClO composited paper-based sensing material was successfully constructed. The RGB/gray value was obtained from a mobile phone and computer, which could achieve the quantitative detection of HClO, with a linear detection range of 0-50 µM and a detection limit of 1.09 µM (RGB mode)/3.38 µM (gray mode). The function of the paper-based sensor extended from qualitative to quantitative detection of HClO, and it is expected to become a portable device widely used in the environmental area.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Células HeLa , Humanos , Ácido Hipocloroso/análise
8.
Phys Chem Chem Phys ; 24(37): 22580-22588, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36102796

RESUMO

Three biphenyl co-sensitizers (4OBA, 8OBA and 12OBA) with different terminal oxyalkyl chains were synthesized and co-sensitized respectively with the main dye (NP-1) in co-sensitized solar cells (co-DSSCs). The effects of the terminal oxyalkyl chains on the photophysical, electrochemical and photovoltaic properties of the co-DSSCs were systematically investigated. The optimal molecular matching relationship between the co-sensitizers and the main dye was obtained through density functional theory (DFT) calculations. Consequently, 4OBA has the most appropriate three-dimensional (3D) molecular structure, which could not only fill the gap between the large-size dyes but also plays a partial shielding role, inhibiting dye aggregation and electron recombination, therefore yielding the highest power conversion efficiency (PCE) for the co-DSSCs with NP-1@4OBA. This study suggests that adjusting the terminal oxyalkyl chains of the co-sensitizers can be used to enhance the intramolecular charge transfer efficiency and inhibit electron recombination, ultimately improving the photovoltaic performances of the co-DSSCs.

9.
Eur J Clin Invest ; 51(2): e13446, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33128454

RESUMO

BACKGROUND: Noninvasive methods have been used for the assessment of hepatic steatosis in patients with nonalcoholic fatty liver disease (NAFLD). The aim was to assess the efficacy and accuracy of both magnetic resonance imaging(MRI) and transient elastography(TE) for the evaluation of hepatic steatosis. MATERIALS AND METHODS: The PubMed, Cochrane Library, Embase, MEDLINE and Web of Science databases were searched to retrieve studies examining the accuracy of MRI-proton density fat fraction(PDFF) and TE-controlled attenuation parameter(CAP) for evaluating the grading of steatosis(S0-S3) diagnosed by liver biopsy in NAFLD. We compared the sensitivity, specificity, hierarchical summary receiver operating characteristic curves(HSROC) and clinical utility of these methods. RESULTS: Twenty-four articles with a total of 2979 patients with NAFLD were included. The steatosis distribution was 8.1%/35.1%/32.2%/24.6% for S0/S1/S2/S3. For the diagnostic accuracy of MRI-PDFF, the HSROCs were 0.97 for ≥S1, 0.91 for ≥S2 and 0.90 for ≥S3. For the diagnostic accuracy of TE-based CAP, the HSROCs were 0.85 for ≥S1, 0.83 for ≥S2 and 0.79 for ≥S3. Following a 'positive' measurement (over the threshold value) for ≥S1, the corresponding post-test probabilities of PDFF and CAP for the presence of steatosis were 82% and 61%, respectively, when the pretest probability was 24%. If the values were below these thresholds ('negative' results), the post-test probabilities were 3% and 7%. CONCLUSION: MRI-PDFF and TE-CAP both provide highly accurate noninvasive approaches for quantifying and staging hepatic steatosis in NAFLD. Compared with TE-CAP, MRI-PDFF is significantly more accurate for evaluating dichotomized grades of steatosis.


Assuntos
Técnicas de Imagem por Elasticidade , Imageamento por Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença
10.
Inorg Chem ; 60(19): 14602-14612, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34551514

RESUMO

The dialanes [(dpp-Bian)Al-Al(dpp-Bian)] (1) and [(dpp-dad)Al(THF)-(THF)Al(dpp-dad)] (2) (dpp-Bian = 1,2-[(2,6-iPr2C6H3)NC]2C12H6, dpp-dad = [(2,6-iPr2C6H3)NC(CH3)]2) react with some isothiocyanates, isocyanates, and diphenylketene via [2 + 4] cycloaddition of the C═O or C═S bond across the C═C-N-Al fragment to afford complexes [L(X═C-Y)Al-Al(X═C-Y)L] with an intact Al-Al single bond (3, L = dpp-Bian, X = PhN, Y = O; 4, L = dpp-Bian, X = Ph2C, Y = O; 6, L = dpp-dad, X = BnN, Y = S; 7, L = dpp-dad, X = tBuN, Y = O; 8, L = dpp-dad, X = iPrN, Y = S; and 9, L = dpp-dad, X = CyN, Y = S). A mixed C═N and C═O mode cycloadduct, [(dpp-Bian)(TosN═C-O)Al-Al(TosN-C═O)(dpp-Bian)] 5, was obtained in the reaction of 1 with tosylisocyanate. Heating the solution of 3 resulted in a thermal transformation and a change of the cycloaddition mode from C═O to C═N to give the product [(dpp-Bian)(PhN-C═O)Al(O)Al(PhN-C═O)(dpp-Bian)] 10. The reduction of 7 and 8 with Na yielded the products [Na(THF)n]2[(dpp-dad-H)(X═C-Y)Al]2 (12, X = iPrN, Y = S, n = 2 and 13, X = tBuN, Y = O, n = 3) in which one of the methyl groups of the backbone of the initial dpp-dad ligand was dehydrogenated. When 2 was reacted with the bulky adamantyl isocyanate AdNCO, the C-C coupling of two substrates occurred to form 14 [(dpp-dad)Al(O═C-NAd)2Al(dpp-dad)] in which the coupled dianionic oxamide ligand bridged two Al atoms in a µ,η4-N,O/N,O mode. Moreover, in the presence of 2.0 equiv of Na metal, precursor 2 reacts with tBuNCS, p-TolylNCS, or Me3SiNCO, possibly through the reduced AlI intermediate, to yield the sulfur- or oxygen-bridged dimer [Na(solv)n]2[(dpp-dad)Al(µ-E)]2 (15, E = S, solv = THF, n = 3 and 16, E = O, solv = DME, n = 2) upon C═S or C═O bond cleavage. Dialane 1 reacts with dimethylsulfone to give a Lewis adduct [(dpp-Bian)(Me2SO2)Al]2 (17), which releases dimethylsulfone upon heating. The diamagnetic compounds 3-10 and 12-17 were characterized by NMR and IR spectroscopy. The molecular structures of 3-17 were established by single-crystal X-ray diffraction analysis. Electronic structures of the compounds and possible isomers have been examined by DFT calculations.

11.
Nanotechnology ; 33(3)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34638108

RESUMO

Fluorescent carbon dots (CDs) have attracted considerable interest due to their superior optical properties and facile preparation. In this work, O-phenylenediamine and melamine were used as precursors for the one-step hydrothermal synthesis of novel orange emissive CDs (O-CDs) in an aqueous solution. The fluorescence intensity (580 nm) of the O-CDs exhibited a good linear relationship with Ag+in the range of 0.0-50.0µM with the detection limit of 0.289µM. Moreover, the O-CDs were successfully used to determine Ag+in biological samples (Hela cells) because of their low cytotoxicity, and good biocompatibility. Besides, the O-CDs-doped solid-phase detection materials (test paper and hydrogel) were employed to monitor Ag+qualitatively and quantitatively, indicated that the O-CDs had a great capacity for the detection of Ag+in biological and environmental areas. Based on their extraordinary fluorescence property, the O-CDs could also be used as security ink. Overall, based on their excellent fluorescent performance, the CDs in this study have significant potential for practical application toward solid-phase sensing and security ink.

12.
Anal Bioanal Chem ; 413(15): 3945-3953, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33954830

RESUMO

Novel spherical polymer nanoparticles were synthesized by hyperbranched polyethylenimine (hPEI) and 6-hydroxy-2-naphthaldehyde (HNA) via Schiff base reaction (one-pot reaction), which had great advantages in water solubility and green synthesis. Meanwhile, probe PEI-HNA could quickly detect Cu2+ in the range of 0-60 µM in 30 s with the detection limit of 243 nM. The fluorescence of PEI-HNA-Cu2+ could be recovered by the addition of S2- in 50 s with the detection limit of 227 nM. Based on the excellent optical properties, PEI-HNA has been used in the bioimaging of living cells with excellent cell penetrability and low toxicity. More importantly, PEI-HNA has been doped into filter paper, hydrogel, and nanofibrous film to prepare solid-phase sensors, displaying rapid response and excellent sensitivity. Moreover, the low-cost and simple preparation of these sensors offers great potential and possibilities for industrialization, which could help accelerate the development of sensors in environmental and biological fields.


Assuntos
Cobre/análise , Corantes Fluorescentes/química , Nanopartículas/química , Polímeros/química , Enxofre/análise , Células HeLa , Humanos , Espectrometria de Fluorescência/métodos
13.
Chemistry ; 25(35): 8259-8267, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-30892746

RESUMO

Digallane [L1 Ga-GaL1 ] (1, L1 =dpp-bian=1,2-[(2,6-iPr2 C6 H3 )NC]2 C12 H6 ) reacts with RN=C=O (R=Ph or Tos) by [2+4] cycloaddition of the isocyanate C=N bonds across both of its C=C-N-Ga fragments to afford [L1 (O=C-NR)Ga-Ga(RN-C=O)L1 ] (R=Ph, 3; R=Tos, 4). The reactions with both isocyanates result in new C-C and N-Ga single bonds. In the case of allyl isocyanate, the [2+4] cycloaddition across one C=C-N-Ga fragment of 1 is accompanied by insertion of a second allyl isocyanate molecule into the Ga-N bond of the same fragment to afford compound [L1 Ga-Ga(AllN- C=O)2 L1 ] (5) (All=allyl). In the presence of Na metal, the related digallane [L2 Ga-GaL2 ] (2; L2 =dpp-dad=[(2,6-iPr2 C6 H3 )NC(CH3 )]2 ) is converted into the gallium(I) carbene analogue [L2 Ga:]- (2 A), which undergoes a variety of reactions with isocyanate substrates. These include the cycloaddition of ethyl isocyanate to 2 A affording [Na2 (THF)5 ]{L2 Ga[EtN-C(O)]2 GaL2 } (6), cleavage of the N=C bond with release of 1 equiv. of CO to give [Na(THF)2 ]2 [L2 Ga(p-MeC6 H4 )(N-C(O))2 -N(p-MeC6 H4 )]2 (7), cleavage of the C=O bond to yield the di-O-bridged digallium compound [Na(THF)3 ]2 [L2 Ga-(µ-O)2 -GaL2 ] (8), and generation of the further addition product [Na2 (THF)5 ][L2 Ga(CyNCO2 )]2 (9). Complexes 3-9 have been characterized by NMR (1 H, 13 C), IR spectroscopy, elemental analysis, and X-ray diffraction analysis. Their electronic structures have been examined by DFT calculations.

14.
Alcohol Alcohol ; 54(1): 62-69, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30184159

RESUMO

AIMS: Epidemiologic evidence on alcohol consumption increasing the risk of gastroesophageal reflux disease (GERD) is contradictory. This study aimed to investigate the correlation between alcohol consumption and GERD by a meta-analysis of observational studies. SHORT SUMMARY: Gastroesophageal reflux disease (GERD) is a prevalent disease, and the incidence is rising. We conducted a meta-analysis of observational studies, indicating that there was a significant association between alcohol consumption and the risk of GERD. This finding provides important implications for the prevention and control of GERD. METHODS: Two investigators retrieved relevant studies on PubMed, Cochrane and EMBASE, respectively. The summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by random effects model to assess the association. Heterogeneity was quantified using the Q statistic and I2. Subgroup analysis, publication bias and sensitivity analysis were also conducted. RESULTS: Twenty-six cross-sectional studies and three case-control studies were included in the meta-analysis. The pooled random effects OR was 1.48 (95%CI, 1.31-1.67; I2 = 88.8%), in comparison between drinkers and non-/occasional drinkers. For reflux esophagitis and non-erosive reflux disease, two subtypes of GERD, the ORs were 1.78 (95%CI, 1.56-2.03; I2 = 87.5%) and 1.15 (95%CI, 1.04-1.28; I2 = 0.3%), respectively. In addition, the pooled OR for drinkers who drank <3-5 times or days per week was 1.29 (95%CI, 1.14-1.46; I2 = 35.5%), while for those who drank more frequently, the OR was 2.12 (95%CI, 1.63-2.75; I2 = 55.1%). Dose-response analysis showed a linear association between alcohol consumption and GERD (Pfornonlinearity=0.235). The pooled OR for a 12.5 g/day increment of alcohol was 1.16 (95%CI, 1.07-1.27; P = 0.001). CONCLUSIONS: This meta-analysis provides evidence for a potential association between alcohol drinking and the risk of GERD. The increase in alcohol consumption and frequency showed a stronger association with GERD.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/tendências , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/etiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos de Casos e Controles , Estudos Transversais , Refluxo Gastroesofágico/epidemiologia , Humanos , Estudos Observacionais como Assunto , Fatores de Risco
15.
Chemistry ; 24(56): 14994-15002, 2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30016556

RESUMO

Whereas the chemistry of single-bond activation by compounds of the main group elements has undergone some development in recent years, the cleavage of multiple bonds remains underexplored. Herein, the reactions of two digallanes bearing α-diimine ligands, namely, [L1 Ga-GaL1 ] (1, L1 =dpp-dad=[(2,6-iPr2 C6 H3 )NC(CH3 )]2 ) and [L2 Ga-GaL2 ] (2, L2 =dpp-bian=1,2-[(2,6-iPr2 C6 H3 )NC]2 C10 H6 ), with isothiocyanates are reported. Reactions of 1 or 2 with isothiocyanates in 1:2 molar ratio proceeded with [2+4] cycloaddition of the C=S bond across the C2 N2 Ga metallacycle with formation of C-C and S-Ga single bonds to afford [L1 (RN=C-S)Ga-Ga(S-C=NR)L1 ] (3, R=Me; 4, R=Ph) and [L2 (RN=C-S)Ga-Ga(S-C=NR)L2 ] (8, R=allyl; 9, R=Ph). In the cases of 8 and 9, this cycloaddition is reversible. The digallanes reacted with 2 equiv of PhNCS in the presence of Na metal or at high temperatures through a unique reductive cleavage of the C=S bond to yield the disulfide-bridged digallium species [Na(THF)3 ]2 [L1 Ga(µ-S)2 GaL1 ] (5), [L2 Ga(µ-S)2 GaL2 ] (10), and [Na(DME)3 ][L2 Ga(µ-S)2 GaL2 ] (11). Moreover, products 4 and 5 can further react with an excess of isothiocyanate, through cleavage of the C=S bond or cycloaddition, to give the bis- or mono-S-bridged complexes [Na(THF)2 ]2 [L1 (PhN=C-S)Ga(µ-S)2 Ga(S-C=NPh)L1 ] (6) and [L1 (PhN=C-S)Ga(µ-S)Ga(S-C=NPh)L1 ] (7). All the newly prepared compounds were characterized by elemental analysis, single-crystal X-ray diffraction, IR spectroscopy, NMR (3-9) or ESR spectroscopy (11), and DFT calculations.

16.
Helicobacter ; 23(1)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29266548

RESUMO

BACKGROUND: Helicobacter pylori is coexisted with various diseases, including chronic gastritis, ulcer, and gastric cancer. Besides, chronic cholecystitis and cholelithiasis are extremely widespread over the world, which are considered as high health-care cost burdens of digestive diseases. Epidemiologic evidence on Helicobacter pylori infection in gallbladder increasing the risk of biliary diseases has been contradictory. AIM: Conduct a meta-analysis of overall studies and investigate an association between Helicobacter pylori infection of the gallbladder with chronic cholecystitis/cholelithiasis. METHODS: We used PubMed, EMBASE, and Cochrane library databases to identify all published studies before August 2017. Pooled odds ratios (OR) and corresponding 95% confidence intervals (CIs) were obtained using the random effects model. Heterogeneity, sensitivity, and stratified analyses were also performed. RESULTS: Eighteen studies involving 1544 participants and 1061 biliary cases with chronic cholecystitis/cholelithiasis were included. Helicobacter pylori infection of the gallbladder was significantly associated with an increased risk of chronic cholecystitis and cholecystitis (OR = 3.022; 95% CI, 1.897-4.815; I2  = 20.1%). In addition, country-based subgroup analysis also showed a positive association between Helicobacter pylori positivity and chronic cholecystitis/cholelithiasis risk. The ORs (95% CIs) for Asian and non-Asian region studies were 3.75 (1.83-7.71) and 2.25 (1.29-3.89), respectively. CONCLUSION: This meta-analysis suggests that infection of the gallbladder with Helicobacter pylori is closely related to an increased risk of chronic cholecystitis and cholelithiasis.


Assuntos
Colecistite/complicações , Colelitíase/complicações , Vesícula Biliar , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Helicobacter pylori , Colecistite/microbiologia , Colelitíase/microbiologia , Doença Crônica , Vesícula Biliar/microbiologia , Vesícula Biliar/patologia , Humanos , Razão de Chances , Risco
17.
J Fluoresc ; 27(6): 2111-2117, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28785903

RESUMO

A novel fluorescein-based dual probe was designed and synthesized. The probe exhibited highly sensitive and selective colormetric response to Fe3+ and turn-on fluorescence response towards OCl- with very low detection limits of 100 and 50 nM, respectively. It was successfully applied for quantitative detection of Fe3+ and OCl- in real water samples. Moreover, probe 1 was expected to be a potentially powerful tool for studying and providing further insights into OCl- and Fe3+ chemistry in the near future.

18.
IEEE Trans Cybern ; 54(7): 4111-4123, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38289845

RESUMO

In this article, a distributed output-feedback consensus maneuvering problem is investigated for a class of uncertain multiagent systems with multi-input and multi-output (MIMO) strict-feedback dynamics. The followers are subject to immeasurable states and external disturbances. A distributed neural observer-based adaptive control method is designed for consensus maneuvering of uncertain MIMO multiagent systems. The method is based on a modular structure, resulting in the separation of three modules: 1) a variable update law for the parameterized path; 2) a high-order neural observer; and 3) an output-feedback consensus maneuvering control law. The proposed distributed neural observer-based adaptive control method ensures that all followers agree on a common motion guided by a desired parameterized path, and the proposed method evades adopting the adaptive backstepping or dynamic surface control design by reformulating the dynamics of agents, thereby reducing the complexity of the control structure. Combined with the cascade system analysis and interconnection system analysis, the input-to-state stability of the consensus maneuvering closed loop is established in the Lyapunov sense. A simulation example is presented to demonstrate the performance of the proposed distributed neural observer-based adaptive control method for output-feedback consensus maneuvering.

19.
ACS Appl Mater Interfaces ; 16(6): 7768-7779, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38294427

RESUMO

Hydrogels are increasingly used in flexible electronic devices, but the mechanical and electrochemical stabilities of hydrogel devices are often limited under specific harsh conditions. Herein, chemically/physically cross-linked double-network (DN) hydrogels containing binary cations Zn2+ and Li+ are constructed in order to address the above challenges. Double networks of chemically cross-linked polyacrylamide (PAM) and physically cross-linked κ-Carrageenan (κ-CG) are designed to account for the mechanical robustness while binary cations endow the hydrogels with excellent ionic conductivity and outstanding environmental adaptability. Excellent mechanical robustness and ionic conductivity (25 °C, 2.26 S·m-1; -25 °C, 1.54 S·m-1) have been achieved. Utilizing the DN hydrogels containing binary cations as signal-converting materials, we fabricated flexible mechanosensors. High gauge factors (resistive strain sensors, 2.4; capacitive pressure sensors, 0.82 kPa-1) and highly stable sensing ability have been achieved. Interestingly, zinc-ion hybrid supercapacitors containing the DN hydrogels containing binary cations as electrolytes have achieved an initial capacity of 52.5 mAh·g-1 at a current density of 3 A·g-1 and a capacity retention rate of 82.9% after 19,000 cycles. Proper working of the zinc-ion hybrid supercapacitors at subzero conditions and stable charge-discharge for more than 19,000 cycles at -25 °C have been demonstrated. Overall, DN hydrogels containing binary cations have provided promising materials for high-performance flexible electronic devices under harsh conditions.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123791, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38134656

RESUMO

Water content was an essential indicator in organic solvents, and it was necessary to develop a facile, cheap and readily available tool for the real-time, specifical and sensitive detection of water content. In this work, two novel D-π-A type near-infrared fluorescence sensors (DCM-1 and DCM-2) were designed and synthesized for the detection of trace water in organic solvents. DCM-1 and DCM-2 with solvent-dependent effects and large Stokes shift (>120 nm) showed good linear "intensity-to-content" relationships in four commonly-used organic solvents, and accomplished the ultra-fast and high-accuracy detection of the trace water in organic solvents. More importantly, a portable, fast, and accurate smartphone-assisted visual assay was designed for visual quantitative detection of the water content in organic solvents with a detection limit as low as 1.028 % v/v (e.g. in ethanol) and a wide detection range (0-60 % v/v). The smartphone-based visual assay was further applied to estimate the water content in disinfection alcohol and commercial liquor, which furnished a new strategy and broad prospects to achieve the accurate onsite detection of water content.


Assuntos
Smartphone , Água , Bebidas Alcoólicas , Solventes , Etanol , Corantes Fluorescentes
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