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1.
Opt Express ; 31(24): 40824-40835, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041373

RESUMO

The self-healing phenomenon of structured light beams has been comprehensively investigated for its important role in various applications including optical tweezing, superresolution imaging, and optical communication. However, for different structured beams, there are different explanations for the self-healing effect, and a unified theory has not yet been formed. Here we report both theoretically and experimentally a study of the self-healing effect of structured beams in lenslike media, this is, inhomogeneous lenslike media with a quadratic gradient index. By observing the appearance of a number of shadows of obstructed structured wave fields it has been demonstrated that their self-healing in inhomogeneous media are the result of superposition of fundamental traveling waves. We have found that self-healing of structured beams occurs in this medium and, interestingly enough, that the shadows created in the process present sinusoidal propagating characteristics as determined by the geometrical ray theory in lenslike media. This work provides what we believe to be a new inhomogenous environment to explain the self-healing effect and is expected to deepen understanding of the physical mechanism.

2.
Langmuir ; 39(35): 12384-12391, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37607010

RESUMO

A series of carbazole-based vinyl-benzoxazole derivatives have been synthesized in order to verify whether X-ray diffraction (XRD) simulation can give more information about intermolecular stacking in the gel phase. It was found that their gelation capabilities were strongly dependent on the length of the alkyl chain. The compounds with shorter alkyl chains have lower critical gelation concentrations (CGCs) in nonpolar alkane and alcohols with longer carbon chains. On the other hand, compounds with long alkyl chains presented small CGCs in polar methanol. Powder XRD structure solution gave more information about intermolecular stacking than the traditional way of analyzing diffraction peaks to derive approximate molecular stacking patterns. The results verified that gelators had a similar head-to-tail π-stacking between aromatic groups in gel phases although different slipping angles existed. Moreover, ordered stacking between the alkyl chains was also present.

3.
Angew Chem Int Ed Engl ; 62(48): e202311348, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37828622

RESUMO

Flexible crystals that can capture solar energy and convert it into mechanical energy are promising for a wide range of applications such as information storage and actuators, but obtaining them remains a challenge. Herein, an elastic crystal of a barbiturate derivative was found to be an excellent candidate, demonstrating plastic bending behavior under natural sunlight irradiation. 1 H NMR and high-resolution mass spectrum data of microcrystals before and after light irradiation demonstrated that light-induced [2+2] cycloaddition was the driving force for the photomechanical effects. Interestingly, the crystals retained elastic bending even after light irradiation. This is the first report of flexible crystals that can be driven by natural sunlight and that have both photomechanical properties and elasticity. Furthermore, regulation of the passive light output direction of the crystals and transport of objects by applying mechanical forces and light was demonstrated.

4.
Chemistry ; 27(64): 16036-16042, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34559422

RESUMO

Elastic organic single crystals with light-emitting and multi-faceted bending properties are extremely rare. They have potential application in optical materials and have attracted the extensive attention of researchers. In this paper, we reported a structurally simple barbituric derivative DBDT, which was easily crystallized and gained long needle-like crystals (centimeter-scale) in DCM/CH3 OH (v/v=2/8). Upon applying or removing the mechanical force, both the (100) and (040) faces of the needle-like crystal showed reversible bending behaviour, showing the nature of multi-faceted bending. The average hardness (H) and elastic modulus (E) were 0.28±0.01 GPa and 4.56±0.03 GPa for the (040) plane, respectively. Through the analysis of the single crystal data, it could be seen that the van der waals (C-H⋅⋅⋅π and C-H⋅⋅⋅C), H-bond (C-H⋅⋅⋅O) and π⋅⋅⋅π interactions between molecules were responsible for the generation of the crystal elasticity. Interestingly, elastic crystals exhibited optical waveguide characteristics in straight or bent state. The optical loss coefficients measured at 627 nm were 0.7 dBmm-1 (straight state) and 0.9 dBmm-1 (bent state), while the optical loss coefficient (α) were 1.5 dBmm-1 (straight state) and 1.8 dBmm-1 (bent state) at 567 nm. Notably, the elastic organic molecular crystal based on barbituric derivative could be used as the candidate for flexible optical devices.

5.
Nanotechnology ; 27(41): 415708, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27607837

RESUMO

Plasmonic resonant cavities are capable of confining light at the nanoscale, resulting in both enhanced local electromagnetic fields and lower mode volumes. However, conventional plasmonic resonant cavities possess large Ohmic losses at metal-dielectric interfaces. Plasmonic near-field coupling plays a key role in a design of photonic components based on the resonant cavities because of the possibility to reduce losses. Here, we study the plasmonic near-field coupling in the silver nanorod metamaterials treated as resonant nanostructured optical cavities. Reflectance measurements reveal the existence of multiple resonance modes of the nanorod metamaterials, which is consistent with our theoretical analysis. Furthermore, our numerical simulations show that the electric field at the longitudinal resonances forms standing waves in the nanocavities due to the near-field coupling between the adjacent nanorods, and a new hybrid mode emerges due to a coupling between nanorods and a gold-film substrate. We demonstrate that this coupling can be controlled by changing the gap between the silver nanorod array and gold substrate.

6.
Appl Opt ; 55(18): 4871-6, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27409112

RESUMO

Tuning transversal resonance modes of localized surface plasmons (LSPs) by the size and the ambient dielectric medium of Ag nanorods is presented. It is found that the resonance wavelength and intensity of the transversal modes of LSPs are closely related to the dimensions of the Ag nanorods embedded in anodic aluminum oxide membranes. The transversal resonance peak exhibits obvious redshifts from 365 to 396 nm with increasing nanorod diameter from 40 to 80 nm, and the resonance intensity remarkably enhances with increasing nanorod diameter. In addition, it is observed that the transversal resonance modes of LSPs in Ag nanorods are strongly sensitive to their surrounding dielectric medium such as water, ethanol, and cetyltrimethylammonium bromide, and the transversal resonance peak distinctly redshifts from 422 to 467 nm when the refractive index of the dielectric medium increases from 1.342 to 1.435. As a result, a refractive index sensitivity of up to 484 nm/RIU can be achieved based on the transversal resonance modes. The transverse resonance modes of LSPs in the Ag nanorods can be used for sensitive quantification of chemical and biological species.

7.
Langmuir ; 29(1): 417-25, 2013 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-23231048

RESUMO

A glutamide gelator, 1, was synthesized, and a weak emission enhancement was observed during its gelation. In addition, 1 could be an excellent scaffold for successfully embedding an energy acceptor, 2, into its aggregate to obtain highly efficient energy transfer. An amplification of the emission enhancement was observed in the two-component gels compared to that of the neat gel of 1 during gel formation. For example, 1 induced only a 2.5-fold increase in emission intensity, whereas a 23-fold enhanced emission could be observed in the two-component gel with only 1.6 mol % 2. Furthermore, two-component gels had an excited proton response. In systems with low acceptor concentrations, the hot solution red-shifted the fluorescence from blue to yellow upon the addition of a proton, which continuously blue-shifted with decreasing temperature to form the gel given that the binding of the gelator to the proton is weakened during coassembly. Moreover, the casting film formed by the two-component wet gel had an excellent response to volatile acids such as hydrochloric acid, trifluoroacetic acid, and so on and could be reversibly recovered by exposure to NH(3).

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 290: 122190, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36577247

RESUMO

In this work, an AIE-active tetraphenylethene-based Schiff base fluorescent probe 3 with a large Stokes shift (247 nm) was designed and synthesized. It was found that the aggregated probe 3 exhibited very high selectivity and anti-interference ability for Cu2+ in PBS buffer (70% fw) through a fluorescence "turn-off" strategy. Job's plot and NMR analysis indicated the two phenolic hydroxyl groups of the benzene ring and the N atom (-CH=N-) on probe 3 interacted with Cu2+ ions in a 1:1 stoichiometric ratio. A comprehensive analysis of the Stern-Volmer and binding constant indicated a rather strong interaction between probe 3 and Cu2+ ions. Probe 3 illustrated excellent sensitivity toward Cu2+ under ppb level (4.5 nM) and achieved more than 95% recovery in river, lake and tap water toward estimation of Cu2+ ions in the analytical applications. Moreover, probe 3 was able to realize bioimaging of HepG2 cells and be quenched by intracellular Cu2+ ions, making it promising as a sensitive Cu2+ sensor for organisms.


Assuntos
Cobre , Bases de Schiff , Bases de Schiff/química , Cobre/análise , Espectrometria de Fluorescência/métodos , Íons/análise , Água/química , Corantes Fluorescentes/química
9.
Chemistry ; 18(12): 3549-58, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22362577

RESUMO

A gelator that consisted of one benzimidazole moiety and four amide units was used as a chemosensor. We found that its absorption and emission spectra in solution were sensitive to two complementary chemical stimuli: protons and anions. Thus, YES and INH logic gates were obtained when absorbance was defined as an output. A combination gate of XNOR and AND with an emission output was also obtained. Moreover, wet gels in two solvents were used to construct two more-complicated three-input-three-output gates, owing to the existence of the gel phase as an additional output. Finally, in xerogel films that were formed from two kinds of wet gels, reversible changes in their emission spectra were observed when they were sequentially exposed to volatile acid and NH(3). Another combination two-output logic gate was obtained for xerogel films. Finally, three states of the gelator were used to construct not only basic logic gate, but also some combination gates because of their response to multiple chemical stimuli and their multiple output signals, in which one chemical input could erase the effect of another chemical input.

10.
Org Biomol Chem ; 10(43): 8701-9, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23033062

RESUMO

We have synthesized new D-A-D type phosphorus(V) porphyrin derivatives and functionalized with axial carbazolylvinylnaphthalimide units. The absorption bands of the obtained phosphorus(V) porphyrins were in the range 250-640 nm with high molar absorption coefficients, meaning strong light-harvesting abilities. Notably, it is found that the devices based on phosphorus(V) porphyrins with a configuration structure of [ITO/PEDOT : PSS/organic active film/LiF/Al] give an incident-photon-to-current conversion efficiency (IPCE) response. The maximal IPCE value reaches 2.76% for the device based on compound , which is much higher than that of 0.20% for compound . The reason might be due to the low oxidation potential and the strong light-harvesting ability of the enlarged conjugation of the axial units in compound . Therefore, we deduced that photo-induced electron transfer happened in phosphorus(V) porphyrins bearing axial conjugated donor units, which would make them good candidates for photovoltaic materials that could be applied in solar cells.


Assuntos
Naftalimidas/química , Fósforo/química , Porfirinas/síntese química , Compostos de Vinila/química , Estrutura Molecular , Processos Fotoquímicos , Porfirinas/química , Teoria Quântica
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(3): 865-869, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35680819

RESUMO

OBJECTIVE: To analyze and evaluate the efficacy of Rh phenotype matched blood transfusion. METHODS: The increasing of hemoglobin (Hb) and hemolysis tests in the patients treated by Rh matched red blood cells or not, as well as the first time unmatched transfusions and the unmatched transfusions happened again after a period (≥10 d) were retrospectively analyzed. RESULTS: A total of 674 times transfusions in 120 patients were evaluated. The increasing of Hb in each unit was higher in the patients treated by Rh matched blood transfusion (vs unmatched) [(33.397±1.475) g/U vs (29.951±1.304) g/U, P=0.033], while the increasing of Hb at first time unmatched transfusion and the second time unmatched transfusion was not statistically different[ (28.942±2.083) g/U vs (30.686±1.737) g/U, P=0.589]. The level of lactate dehydrogenase were related to erythrocyte washing, irradiation, period of validity and the second time unmatched transtusion (all P<0.05); the levels of total bilirubin (TBil), direct bilirubin (DBil) and indirect bilirubin (IBil) between the first time unmatched transfusion and the second time unmatched transfusion were statistically different (all P<0.05). CONCLUSION: For the patients need multiple blood transfusions, Rh phenotype matched blood transfusion can reduce the exposure to Rh allogenic antigens, improve the efficacy and ensure the safety of blood transfusion.


Assuntos
Transfusão de Sangue , Transfusão de Eritrócitos , Bilirrubina , Transfusão de Eritrócitos/efeitos adversos , Hemoglobinas/análise , Humanos , Fenótipo , Estudos Retrospectivos
12.
Front Oncol ; 12: 1022426, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276137

RESUMO

Background: Pseudomyxoma peritonei is a rare disease that presents as a malignant tumor on the peritoneal surface. Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy is the standard treatment for this disease and frequently requires a red blood cell transfusion. However, due to the limited collection and supply of allogeneic blood, surgical treatment may be delayed due to inadequate preparation of allogeneic blood in the course of clinical treatment. This study aimed to evaluate the safety and efficacy of transfusion of stored autologous blood in patients with low-grade pseudomyxoma peritonei. Methods: Pseudomyxoma peritonei patients who received cytoreductive surgery combined with heat-infused peritoneal chemotherapy were divided into two groups: transfusion of allogeneic blood and transfusion of stored autologous blood. A comparison of the differences in multiple factors between the two groups was performed, including tumor recurrence, survival time, hemoglobin and hematocrit levels, coagulation function (prothrombin time, activated partial thromboplastin time, and fibrinogen), total hospital stay duration, and incidence of serious adverse events after surgery. Results: Propensity scores matching analysis yielded 34 patients with allogeneic blood transfusion and 34 patients with stored autologous blood transfusion. Comparison analysis did not show statistical differences in several factors, including age, tumor grade, tumor recurrence rate after surgery, etc., between the two groups. The cytoreductive degree was considered an independent risk factor for tumor recurrence. The pseudomyxoma peritonei patients in the autologous transfusion group had a higher 5-year survival rate and a longer survival time. Moreover, transfusion of stored autologous blood did not increase the rate of tumor recurrence, or the total hospital stay duration after surgery, the hemoglobin level and coagulation function were well stabilized within 24 h after surgery, and there was a low incidence of serious adverse events. Conclusion: The clinical application of transfusion of stored autologous blood in pseudomyxoma peritonei patients is safe and effective.

13.
Org Biomol Chem ; 9(5): 1523-8, 2011 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21225081

RESUMO

A new dendritic gelator with carbazole as the building block (HBCD) was synthesized. It was found that H-bonding between the amide groups and π-π interaction between the aromatic rings played predominant roles in the gel formation. Meanwhile, significant aggregation-induced emission enhancement was observed in the gel state due to the formation of J-aggregates and the restricted molecular motion. Notably, the gel state of HBCD can be destroyed upon addition of F(-), accompanied by fluorescence enhancement on account of the formation of N-HF(-), which could further lead to the increased coplanarity of HBCD. The sensory capability of HBCD exhibited a high selectivity towards F(-) instead of the Cl(-), Br(-), I(-) and AcO(-) anions, which could be explained by the fact that the steric hindrance of the dendrimer would go against the interactions between the larger anions and HBCD.

14.
Org Biomol Chem ; 8(19): 4289-96, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20714664

RESUMO

Two simple molecules, 1 and 2 with D-pi-A structure and alkoxyl groups, respectively, were designed and synthesized. Both compounds can gelatinize THF-water and DMSO. And compound 2 forms gel in acetone by ultrasonic stimulus. Interestingly, these gels exhibit aggregation-induced emission (AIE) during the sol-gel phase transformation. Moreover, the molecular self-assembled and photophysical properties can be controlled by the number of the alkoxyl chains and the type of the solvents. For example, 1 has an identical packing model and fluorescent colour in THF-water and DMSO gels. Contrarily, the self-assembly of molecule 2 strongly depends on the solvent. Furthermore, the gel phases of 2 formed in three solvents possess different fluorescent colours. Such as, THF-water gel emits yellow fluorescence, acetone gel has orange emission and red fluorescence appears in DMSO.

15.
Adv Healthc Mater ; 5(22): 2911-2921, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27709830

RESUMO

Peptide-based therapy, such as modified peptides, has attracted increased attention. IL-17 is a promising therapeutic target for autoimmune diseases, and levels of circulating bioactive IL-17 are associated with rheumatoid arthritis severity. In this study, a modified truncated IL-17RC is generated to ameliorate inflammation and bone destruction in arthritis. The truncated IL-17RC binds to both IL-17A and IL-17F with higher binding capacity compared to nonmodified IL-17RC. In addition, the truncated IL-17RC reduces the secretion of inflammatory and osteoclastogenic factors induced by IL-17A/F in vitro. Moreover, the administration of truncated IL-17RC dramatically improves symptoms of inflammation and inhibited bone destruction in collagen-induced arthritis mice. Collectively, these data demonstrate that modified truncated IL-17RC peptide may be a more effective treatment strategy in the simultaneous inhibition of both IL-17A and IL-17F signaling, whereas the existing agents neutralize IL-17A or IL-17F alone. These suggest that the truncated IL-17RC may be a potential candidate in the treatment of inflammatory associated bone diseases.


Assuntos
Artrite Experimental/tratamento farmacológico , Doenças Ósseas/tratamento farmacológico , Interleucina-17/administração & dosagem , Peptídeos/administração & dosagem , Sinovite/tratamento farmacológico , Sequência de Aminoácidos , Animais , Artrite Reumatoide/tratamento farmacológico , Sequência de Bases , Osso e Ossos/efeitos dos fármacos , Linhagem Celular , Inflamação/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Células RAW 264.7
16.
Chem Commun (Camb) ; 50(20): 2569-71, 2014 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-24419226

RESUMO

A triphenylamine-based benzoxazole derivative exhibits a low contrast piezofluorochromic behavior under external pressure, and a high-contrast fluorescence change induced by protonation can be observed.

17.
Biomaterials ; 33(32): 8177-85, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22884682

RESUMO

Targeting tumor necrosis factor-α (TNF-α) and activator of NF-κB ligand (RANKL) has been proved highly successful in rheumatoid arthritis (RA) models and patients. This raises a possibility whether a single agent simultaneously targeting TNF-α and RANKL provides a potential therapeutic opportunity. This study aimed to design a dual functional vaccine and evaluate its therapeutic effects in RA mice model. Standard molecular biological techniques were used to generate human RANKL-TNF-like core fusion protein (RTFP-2) vaccine. High titers of antibodies against human TNF-α and RANKL were elicited and the RTFP-2 antiserum decreased TNF-α mediated apoptosis of L929 cells to 41% compared with 90% in positive controls. In addition, the antiserum completely abrogated osteoclastogenesis in vitro. Immunization with RTFP-2 also reduced the mortality of TNF-α induced cachexia from 56% to 28%. The RANKL-mediated hypercalcemic effects were significantly attenuated in RTFP-2 vaccinated mice. Furthermore, RTFP-2 vaccine significantly mitigated the incidence and severity of CIA via inhibition of inflammation and bone resorption. Our results showed the RTFP-2 vaccine of dual targets ameliorated the symptoms of CIA mice, suggesting the potential possibility to treat inflammatory bone diseases such as RA.


Assuntos
Artrite Experimental/prevenção & controle , Ligante RANK/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Fator de Necrose Tumoral alfa/uso terapêutico , Vacinas/uso terapêutico , Sequência de Aminoácidos , Animais , Formação de Anticorpos , Artrite Experimental/imunologia , Artrite Experimental/patologia , Osso e Ossos/imunologia , Osso e Ossos/patologia , Linhagem Celular , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Ligante RANK/química , Ligante RANK/genética , Ligante RANK/imunologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Fator de Necrose Tumoral alfa/química , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Vacinas/química , Vacinas/genética , Vacinas/imunologia
18.
Chem Commun (Camb) ; 46(44): 8419-21, 2010 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-20936245

RESUMO

Rigid boomerang shaped triphenylamine functionalized bis-ß-diketone-boron difluoride without alkyl chain and H-bonding unit exhibits good gelation ability in some mixed organic solvents directed by optimally balanced π-π interactions.

19.
J Virol ; 79(16): 10730-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16051865

RESUMO

Hepatitis C virus (HCV) infection is a major global health problem. Hepatic expression of immune costimulatory signaling molecules (e.g., B7) is known to be associated with ongoing liver injury in hepatitis C patients. However, due to the general lack of viral culture systems and adequate animal models, the function of these molecules in disease pathogenesis is poorly understood. To investigate the role of CD86 in HCV-related liver injury, we developed two transgenic mouse lineages with inducible expression of HCV structural proteins and constitutive expression of the costimulatory molecule CD86/B7.2 in the liver. Using a hydrodynamic-based, nonviral delivery protocol, we induced HCV transgene expression in the livers of HCV and CD86 single- and double-transgenic mice. We found that hepatic CD86 expression resulted in increased activation of and cytokine production (e.g., interleukin-2 and gamma interferon) by CD4+ T cells and that the retention of these cells was associated with more pronounced necroinflammatory lesions in the liver. Taken together, these data suggest that augmented, parenchymal antigen presentation conferred by hepatocyte CD86 expression alters homeostasis and effector functions of CD4+ T cells and contributes to liver injury. This study provides an additional rationale for exploring immunomodulation-based therapies that could reduce disease progression in individuals with chronic HCV infection.


Assuntos
Antígenos CD/fisiologia , Hepacivirus/patogenicidade , Fígado/patologia , Glicoproteínas de Membrana/fisiologia , Animais , Antígeno B7-2 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transgenes
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