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1.
Langmuir ; 40(28): 14281-14290, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38967331

RESUMEN

Marine antibiofouling using low-amplitude electric pulses (EP) is an energy-efficient and eco-friendly approach, but potential mechanisms for preventing biofouling remain unclear. In the present study, the 3D adhesion dynamics of a model microorganism─Pseudomonas aeruginosa (PAO1)─under low-amplitude cathodic EP were examined as a function of applying voltage and its duration (td). The results demonstrated that adhered bacteria escaped from the electrode surface even when EP was removed. The escaped bacteria ratio, induction period of escape, and duration of the detachment were influenced profoundly by EP amplitude but slightly by td when td ≥ 5 min. The acceleration of escaped PAO1 from the surface indicated that their flagellar motor was powered by EP. Particularly, EP enabled swimming bacteria to have adaptive motions that were sustainable and regulated by the gene rsmA. As a result, they had less accumulation near the surface. The propulsion of adhered bacteria and adaptive escape of swimming bacteria were enhanced in response to low-amplitude EP. Hence, low-amplitude and short-duration EP is promising for sustainable antibiofouling applications.


Asunto(s)
Adhesión Bacteriana , Pseudomonas aeruginosa , Pseudomonas aeruginosa/fisiología , Electrodos , Electricidad , Incrustaciones Biológicas/prevención & control
2.
J Chem Phys ; 160(5)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38341697

RESUMEN

The topology of a polymer profoundly influences its behavior. However, its effect on imbibition dynamics remains poorly understood. In the present work, capillary filling (during imbibition and following full imbibition) of star polymer melts was investigated by molecular dynamics simulations with a coarse-grained model. The reversal of imbibition dynamics observed for linear-chain systems was also present for star polymers. Star polymers with short arms penetrate slower than the prediction of the Lucas-Washburn equation, while systems with long arms penetrate faster. The radius of gyration increases during confined flow, indicating the orientation and disentanglement of arms. In addition, the higher the functionality of the star polymer, the more entanglement points are retained. Besides, a stiff region near the core segments of the stars is observed, which increases in size with functionality. The proportion of different configurations of the arms (e.g., loops, trains, tails) changes dramatically with the arm length and degree of confinement but is only influenced by the functionality when the arms are short. Following full imbibition, the different decay rates of the self-correlation function of the core-to-end vector illustrate that arms take a longer time to reach the equilibrium state as the functionality, arm length, and degree of confinement increase, in agreement with recent experimental findings. Furthermore, the star topology induces a stronger effect of adsorption and friction, which becomes more pronounced with increasing functionality.

3.
Anal Chem ; 95(2): 1318-1326, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36577742

RESUMEN

Raman spectra are often masked by strong fluorescence, which severely hinders the applications of Raman spectroscopy. Herein, for the first time, we report ionic-wind-enhanced Raman spectroscopy (IWERS) incorporated with photobleaching (PB) as a noninvasive approach to detect fluorescent and vulnerable samples without a substrate. In this study, ionic wind (IW) generated by needle-net electrodes transfers charges to the sample surface in air on the scale of millimeters rather than nanometers in surface-enhanced Raman spectroscopy. Density functional theory calculations reveal that the ionic particles in IW increase the susceptibility of the sample molecules, thus enhancing the Raman signals. Meanwhile, the incorporation of IW with PB yields a synergistic effect to quench fluorescence. Therefore, this approach can improve the signal-to-noise ratio of Raman peaks up to three times higher than that with only PB. At the same time, IWERS can avoid sample pollution and destruction without substrates as well as high laser power. For archeological samples and a red rock as an analogue to Mars geological samples, IWERS successfully identified weak but key Raman peaks, which were masked by strong florescence. It suggests that IWERS is a promising tool for characterizations in the fields of archeology, planetary science, biomedicine, and soft matter.


Asunto(s)
Rayos Láser , Espectrometría Raman , Espectrometría Raman/métodos , Relación Señal-Ruido , Fotoblanqueo
4.
Langmuir ; 39(48): 17308-17317, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-37974298

RESUMEN

The adhesion of probiotics plays an important role in the gastrointestinal tract. Understanding the effect of the coverage of colonized probiotics on enteric pathogens is critical for the design of effective probiotic therapies. In the present work, we have investigated the adaptive behaviors of the intestinal pathogenic bacteria Enterobacter sakazakii (ES) near the surfaces coated with a probiotic─Lactobacillus rhamnosus GG (LGG) as a function of surface coverage ratio (CRLGG) by using a home-setup digital holographic microscopy. It shows that ES cells can adaptively sense LGG within a distance of 4.2 µm, even at CRLGG values as low as 0.05%. The growth inhibition of ES cells slightly varies with CRLGG, but the near-surface acceleration and accumulation of ES cells have much dependence on CRLGG. As CRLGG increases from 0.05 to 24.6%, the percentage of actively swimming ES, the motion bias, the acceleration, and the interplay duration do not linearly vary with CRLGG. Instead, each of them shows an extreme at CRLGG of 13.4%, corresponding to the chemotaxis behaviors of ES cells induced by diffusing stimuli (organic acids, bacteriocins, etc.) released from LGG, which showed an extreme concentration gradient at CRLGG = 13.4% by simulations. Our study clearly demonstrates that surface coverage of sessile probiotics profoundly influences their interplay with pathogen bacteria, which should be taken into account in designing probiotic therapies.


Asunto(s)
Lacticaseibacillus rhamnosus , Probióticos , Microscopía , Tracto Gastrointestinal
5.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1498-1509, 2023 Mar.
Artículo en Zh | MEDLINE | ID: mdl-37005837

RESUMEN

To explore the changes and the reaction mechanisms between soil microecological environment and the content of secon-dary metabolites of plants under water deficit, this study carried out a pot experiment on the 3-leaf stage seedlings of Rheum officinale to analyze their response mechanism under different drought gradients(normal water supply, mild, moderate, and severe drought). The results indicated that the content of flavonoids, phenols, terpenoids, and alkaloids in the root of R. officinale varied greatly under drought stresses. Under mild drought stress, the content of substances mentioned above was comparatively high, and the content of rutin, emodin, gallic acid, and(+)-catechin hydrate in the root significantly increased. The content of rutin, emodin, and gallic acid under severe drought stress was significantly lower than that under normal water supply. The number of species, Shannon diversity index, richness index, and Simpson index of bacteria in the rhizosphere soil were significantly higher than those in blank soil, and the number of microbial species and richness index decreased significantly with the aggravation of drought stresses. In the context of water deficit, Cyanophyta, Firmicutes, Actinobacteria, Chloroflexi, Gemmatimonadetes, Streptomyces, and Actinomyces were the dominant bacteria in the rhizosphere of R. officinale. The relative content of rutin and emodin in the root of R. officinale was positively correlated with the relative abundance of Cyanophyta and Firmicutes, and the relative content of(+)-catechin hydrate and(-)-epicatechin gallate was positively correlated with the relative abundance of Bacteroidetes and Firmicutes. In conclusion, appropriate drought stress can increase the content of secondary metabolites of R. officinale from physiological induction and the increase in the association with beneficial microbe.


Asunto(s)
Catequina , Emodina , Rheum , Rizosfera , Sequías , Suelo , Bacterias/genética , Bacterias/metabolismo , Agua/metabolismo , Firmicutes , Microbiología del Suelo
6.
Nanotechnology ; 33(25)2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35287121

RESUMEN

Strain engineering is an effective means of modulating the optical and electrical properties of two-dimensional materials. The flexoelectric effect caused by inhomogeneous strain exists in most dielectric materials, which breaks the limit of the materials' non-centrosymmetric structure for piezoelectric effect. However, there is a lack of understanding of the impact on optoelectronic behaviour of monolayer MoS2photodetector via local flexoelectric effect triggered by biaxial strain. In this paper, we develop a probe tip (Pt)-MoS2-Au asymmetric Schottky barrier photodetector based on conductive atomic force microscopy to investigate the impact of flexoelectric effect on the photoresponse performance. Consequently, when the probe force increases from 24 nN to 720 nN, the photocurrent, responsivity and detectivity increase 28.5 times, 29.6 times and 5.3 times at forward bias under 365 nm light illumination, respectively. These results indicate that local flexoelectric effect plays a critical role to improve the photoresponse performance of photodetector. Our approach suggests a new route to improve the performance of photodetectors by introducing local flexoelectric polarization field, offering the potential for the application of strain modulated photoelectric devices.

7.
Brain Behav Immun ; 71: 23-27, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29678794

RESUMEN

Inflammatory bowel disease (IBD) is a debilitating immune-related condition that affects over 1.4 million Americans. Recent studies indicate that taste receptor signaling is involved in much more than sensing food flavor, and taste receptors have been localized in a variety of extra-oral tissues. One of the newly revealed functions of taste receptors and downstream signaling proteins is modulation of immune responses to microbes and parasites. We previously found that components of the taste receptor signaling pathway are expressed in subsets of the intestinal epithelial cells. α-Gustducin, a key G-protein α subunit involved in sweet, umami, and bitter taste receptor signaling, is expressed in the intestinal mucosa. In this study, we investigated the role of α-gustducin in regulation of gut mucosal immunity and inflammation using α-gustducin knockout mice in the dextran sulfate sodium (DSS)-induced IBD model. DSS is a chemical colitogen that can cause intestinal epithelial damage and inflammation. We analyzed DSS-induced colitis in α-gustducin knockout versus wild-type control mice after administration of DSS in drinking water. Our results show that the knockout mice had aggravated weight loss, diarrhea, intestinal bleeding, and inflammation over the experimental period compared to wild-type mice, concurrent with augmented immune cell infiltration and increased expression of TNF and IFN-γ but decreased expression of IL-13 and IL-5 in the colon. These results suggest that the taste receptor signaling pathway may play critical roles in regulating gut immune balance and inflammation.


Asunto(s)
Mucosa Intestinal/metabolismo , Transducina/metabolismo , Transducina/fisiología , Animales , Colitis/fisiopatología , Colon/metabolismo , Sulfato de Dextran/farmacología , Modelos Animales de Enfermedad , Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/fisiopatología , Interferón gamma/metabolismo , Mucosa Intestinal/inmunología , Intestinos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/fisiología , Gusto/fisiología , Papilas Gustativas/metabolismo , Transducina/genética , Factor de Necrosis Tumoral alfa/metabolismo
8.
RNA ; 20(4): 568-79, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24563514

RESUMEN

RNase E, a central component involved in bacterial RNA metabolism, usually has a highly conserved N-terminal catalytic domain but an extremely divergent C-terminal domain. While the C-terminal domain of RNase E in Escherichia coli recruits other components to form an RNA degradation complex, it is unknown if a similar function can be found for RNase E in other organisms due to the divergent feature of this domain. Here, we provide evidence showing that RNase E forms a complex with another essential ribonuclease-the polynucleotide phosphorylase (PNPase)-in cyanobacteria, a group of ecologically important and phylogenetically ancient organisms. Sequence alignment for all cyanobacterial RNase E proteins revealed several conserved and variable subregions in their noncatalytic domains. One such subregion, an extremely conserved nonapeptide (RRRRRRSSA) located near the very end of RNase E, serves as the PNPase recognition site in both the filamentous cyanobacterium Anabaena PCC7120 and the unicellular cyanobacterium Synechocystis PCC6803. These results indicate that RNase E and PNPase form a ribonuclease complex via a common mechanism in cyanobacteria. The PNPase-recognition motif in cyanobacterial RNase E is distinct from those previously identified in Proteobacteria, implying a mechanism of coevolution for PNPase and RNase E in different organisms.


Asunto(s)
Cianobacterias/metabolismo , Endorribonucleasas/metabolismo , Oligopéptidos/metabolismo , Polirribonucleótido Nucleotidiltransferasa/metabolismo , ARN Bacteriano/genética , Secuencia de Aminoácidos , Dominio Catalítico , Biología Computacional , Cianobacterias/genética , Cianobacterias/crecimiento & desarrollo , Endorribonucleasas/genética , Immunoblotting , Datos de Secuencia Molecular , Polirribonucleótido Nucleotidiltransferasa/genética , ARN Bacteriano/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Técnicas del Sistema de Dos Híbridos
9.
J Neurosci ; 34(7): 2689-701, 2014 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-24523558

RESUMEN

Although inflammatory responses are a critical component in defense against pathogens, too much inflammation is harmful. Mechanisms have evolved to regulate inflammation, including modulation by the anti-inflammatory cytokine interleukin-10 (IL-10). Previously we have shown that taste buds express various molecules involved in innate immune responses, including the proinflammatory cytokine tumor necrosis factor (TNF). Here, using a reporter mouse strain, we show that taste cells also express the anti-inflammatory cytokine IL-10. Remarkably, IL-10 is produced by only a specific subset of taste cells, which are different from the TNF-producing cells in mouse circumvallate and foliate taste buds: IL-10 expression was found exclusively in the G-protein gustducin-expressing bitter receptor cells, while TNF was found in sweet and umami receptor cells as reported previously. In contrast, IL-10R1, the ligand-binding subunit of the IL-10 receptor, is predominantly expressed by TNF-producing cells, suggesting a novel cellular hierarchy for regulating TNF production and effects in taste buds. In response to inflammatory challenges, taste cells can increase IL-10 expression both in vivo and in vitro. These findings suggest that taste buds use separate populations of taste receptor cells that coincide with sweet/umami and bitter taste reception to modulate local inflammatory responses, a phenomenon that has not been previously reported. Furthermore, IL-10 deficiency in mice leads to significant reductions in the number and size of taste buds, as well as in the number of taste receptor cells per taste bud, suggesting that IL-10 plays critical roles in maintaining structural integrity of the peripheral gustatory system.


Asunto(s)
Interleucina-10/biosíntesis , Papilas Gustativas/citología , Papilas Gustativas/metabolismo , Animales , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunohistoquímica , Hibridación in Situ , Interleucina-10/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Interleucina-10/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Papilas Gustativas/inmunología , Factor de Necrosis Tumoral alfa/biosíntesis
10.
Brain Behav Immun ; 49: 32-42, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25911043

RESUMEN

Inflammatory cytokines are important regulators of metabolism and food intake. Over production of inflammatory cytokines during bacterial and viral infections leads to anorexia and reduced food intake. However, it remains unclear whether any inflammatory cytokines are involved in the regulation of taste reception, the sensory mechanism governing food intake. Previously, we showed that tumor necrosis factor (TNF), a potent proinflammatory cytokine, is preferentially expressed in a subset of taste bud cells. The level of TNF in taste cells can be further induced by inflammatory stimuli. To investigate whether TNF plays a role in regulating taste responses, in this study, we performed taste behavioral tests and gustatory nerve recordings in TNF knockout mice. Behavioral tests showed that TNF-deficient mice are significantly less sensitive to the bitter compound quinine than wild-type mice, while their responses to sweet, umami, salty, and sour compounds are comparable to those of wild-type controls. Furthermore, nerve recording experiments showed that the chorda tympani nerve in TNF knockout mice is much less responsive to bitter compounds than that in wild-type mice. Chorda tympani nerve responses to sweet, umami, salty, and sour compounds are similar between TNF knockout and wild-type mice, consistent with the results from behavioral tests. We further showed that taste bud cells express the two known TNF receptors TNFR1 and TNFR2 and, therefore, are potential targets of TNF. Together, our results suggest that TNF signaling preferentially modulates bitter taste responses. This mechanism may contribute to taste dysfunction, particularly taste distortion, associated with infections and some chronic inflammatory diseases.


Asunto(s)
Quinina , Percepción del Gusto/fisiología , Gusto/fisiología , Factor de Necrosis Tumoral alfa/fisiología , Animales , Conducta Animal/fisiología , Nervio de la Cuerda del Tímpano/fisiología , Ácido Cítrico , Femenino , Inosina Monofosfato , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Sacarina , Cloruro de Sodio , Glutamato de Sodio , Papilas Gustativas/citología , Papilas Gustativas/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
11.
Chem Senses ; 39(1): 3-16, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24287552

RESUMEN

The mammalian taste bud is an onion-shaped epithelial structure with 50-100 tightly packed cells, including taste receptor cells, supporting cells, and basal cells. Taste receptor cells detect nutrients and toxins in the oral cavity and transmit the sensory information to gustatory nerve endings in the buds. Supporting cells may play a role in the clearance of excess neurotransmitters after their release from taste receptor cells. Basal cells are precursor cells that differentiate into mature taste cells. Similar to other epithelial cells, taste cells turn over continuously, with an average life span of about 8-12 days. To maintain structural homeostasis in taste buds, new cells are generated to replace dying cells. Several recent studies using genetic lineage tracing methods have identified populations of progenitor/stem cells for taste buds, although contributions of these progenitor/stem cell populations to taste bud homeostasis have yet to be fully determined. Some regulatory factors of taste cell differentiation and degeneration have been identified, but our understanding of these aspects of taste bud homoeostasis remains limited. Many patients with various diseases develop taste disorders, including taste loss and taste distortion. Decline in taste function also occurs during aging. Recent studies suggest that disruption or alteration of taste bud homeostasis may contribute to taste dysfunction associated with disease and aging.


Asunto(s)
Envejecimiento , Homeostasis , Papilas Gustativas/citología , Trastornos del Gusto/etiología , Animales , Muerte Celular , Diferenciación Celular , Humanos , Papilas Gustativas/metabolismo , Papilas Gustativas/patología , Trastornos del Gusto/metabolismo , Trastornos del Gusto/patología
12.
J Phys Chem Lett ; 15(22): 5923-5934, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38809779

RESUMEN

The implementation of energy-saving policies has stimulated intensive interest in exploring self-powered optoelectronic devices. The 2D p-n homojunction exhibits effective generation and separation of carriers excited by light, realizing lower power consumption and higher performance photodetectors. Here, a self-powered photodetector with high performance is fabricated based on an F4-TCNQ localized molecular-doped lateral InSe homojunction. Compared with the intrinsic InSe photodetector, the switching light ratio (Ilight/Idark) of the p-n homojunction device can be enhanced by 2.2 × 104, and the temporal response is also dramatically improved to 24/30 µs. Benefiting from the built-in electric field, due to the formation of an InSe p-n homojunction after partial doping of F4-TCNQ on InSe, the device possesses a high responsivity (R) of 93.21 mA/W, with a specific detectivity (D*) of 1.14 × 1011 Jones. These results suggest a promising approach to get a lateral InSe p-n homojunction and reveal the potential application of the device for next generation low-consumption photodetectors.

13.
Zhong Yao Cai ; 36(2): 188-90, 2013 Feb.
Artículo en Zh | MEDLINE | ID: mdl-23901639

RESUMEN

OBJECTIVE: To optimize the extracting condition of fatty constituents from Tabanus bivittatus and analyse by GC-MS. METHODS: Taking fatty yield as index, the extraction technology parameters of fatty constituents of Tabanus bivittatus ere optimized by single factor test and orthogonal test. RESULTS: The optimum extraction parameters were as follows: the ratio of acetone to petroleum ether 1: 2, extraction time 2 h, solid-liquid ratio 1: 50. Twenty-one fatty acids were identified by GC-MS. CONCLUSION: The process is reasonable and with good reproducibility. The main components of fatty acids in Tabanus bivittatus are palmitoleic acid, palmitic acid, linoleic acid, oleic acid and stearic acid.


Asunto(s)
Dípteros/química , Ácidos Grasos/análisis , Materia Medica/análisis , Acetona/química , Animales , Ácidos Grasos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Ácido Linoleico/análisis , Materia Medica/aislamiento & purificación , Ácido Oléico/análisis , Ácido Palmítico/análisis , Reproducibilidad de los Resultados , Solventes/química , Factores de Tiempo
14.
Sci Rep ; 12(1): 17536, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-36266397

RESUMEN

Recently, deep neural network-based cognitive models such as deep knowledge tracing have been introduced into the field of learning analytics and educational data mining. Despite an accurate predictive performance of such models, it is challenging to interpret their behaviors and obtain an intuitive insight into latent student learning status. To address these challenges, this paper proposes a new learner modeling framework named the EAKT, which embeds a structured cognitive model into a transformer. In this way, the EAKT not only can achieve an excellent prediction result of learning outcome but also can depict students' knowledge state on a multi-dimensional knowledge component(KC) level. By performing the fine-grained analysis of the student learning process, the proposed framework provides better explanatory learner models for designing and implementing intelligent tutoring systems. The proposed EAKT is verified by experiments. The performance experiments show that the EAKT can better predict the future performance of student learning(more than 2.6% higher than the baseline method on two of three real-world datasets). The interpretability experiments demonstrate that the student knowledge state obtained by EAKT is closer to ground truth than other models, which means EAKT can more accurately trace changes in the students' knowledge state.


Asunto(s)
Conocimiento , Redes Neurales de la Computación , Humanos , Aprendizaje , Atención , Cognición
15.
Carbohydr Polym ; 297: 120041, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36184148

RESUMEN

Overuse of pesticides is an urgent issue to be solved in sustainable agriculture. Based on the synergistic drug loading effect of ß-cyclodextrin (ß-CD) encapsulation and alginate (Alg) cross-linking, a new environment-responsive drug delivery system (TMX-loaded Alg/ß-CD) was constructed. The relationship between carrier structure and solubility of thiamethoxam (TMX) was researched by molecular simulation. ß-CD has good binding affinity with TMX, which can increase TMX solubility by 40 %. Further co-loading with alginate could double the drug loading of the cyclodextrin inclusion complex up to 41 %. TMX-loaded Alg/ß-CD exhibits excellent environment-responsive controlled-release performance, and TMX sustained release time is 7.5 times longer than that of commercial agents. The pest control efficacy of TMX-loaded Alg/ß-CD is 20 days longer than that of commercial TMX, and the crops has no pesticide residues after using. This study provides a promising strategy for the commercial application of polysaccharide in pest control and pesticide reduction.


Asunto(s)
Plaguicidas , beta-Ciclodextrinas , Alginatos/química , Preparaciones de Acción Retardada/química , Polisacáridos , Tamoxifeno/química , Tiametoxam
16.
ACS Appl Mater Interfaces ; 13(49): 59132-59141, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34852461

RESUMEN

Circularly polarized (CP) light has attracted wide attention for its great potential in broad applications. However, it remains a challenge to generate left-handed and right-handed circularly polarized (LCP and RCP) light from cellulose nanocrystal (CNC)-based materials only with an intrinsic left-handed chiral structure, owing to the pattern of CP light emission primarily based on the chirality of materials. Herein, a separation structure of luminophore layers and chiral CNCs was provided to achieve dual-mode CP light emission by building a luminophore-chiral CNC interface. By directly exciting the back and front of two-layer films, LCP and RCP light could be easily emitted without any assisting means and specific setting angles. In addition, owing to the formation of the luminophore-chiral CNC interface, metal-enhanced fluorescence (MEF) was achieved to offset the brightness loss caused by circular polarization. By incorporating gold triangular nanoprisms in CNC chiral layers, the fluorescence enhancement of the ensemble was as high as 6.5-fold. The decisive role of the luminophore-chiral CNC interface in enhancing luminescence and dual-mode CP light emission was carefully investigated by contrasting the systems with and without luminophore-chiral CNC interfaces in this study. We believe that this dual-mode CP light emission film with MEF enables a promising approach to extending the application of CP light materials.

17.
Eur J Pharmacol ; 908: 174357, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34284012

RESUMEN

Neuroinflammation is considered as an important mechanism of vascular dementia (VaD). Our primary study showed that the bisindole analogue (2-(2-(bis(5-chloro-1H-indol-3-yl)methyl)phenoxy)aniline, compound 4ae) had great anti-inflammation in zebrafish. Rat model of permanent occlusion of the bilateral common carotid arteries (2-vessel occlusion, 2VO) was utilized to evaluate the neuroprotective effect of 4ae. Our results showed that 4ae treatment effectively reduced Iba-1 positive microglia cells in cerebral cortex and hippocampus after cerebral ischemia. Compared with the model group, neuroinflammation characterized by Interleukin (IL)-6 and tumor necrosis factor (TNF)-α, oxidative stress characterized by reactive oxygen species (ROS) and superoxide dismutase (SOD) were both improved significantly after treatment with 4ae. Moreover, 4ae treatment significantly reversed ischemia-induced ACE enhancement, while notably increased the level of ACE2. To further elucidate the role of 4ae on neuroinflammation, we investigated the effects of 4ae on lipopolysaccharide (LPS)-induced inflammation in BV2 microglia cells, a kind of innate immune cells in central nervous system. The results demonstrated that the expressions of CD11b, TNFα and IL-6 and the level of ROS were up-regulated after treatment with LPS. More importantly, 4ae was able to block the activation of BV2 by reducing ROS production and the expression of inflammatory cytokines. In addition, our results suggested that 4ae inhibited the inflammatory response mediated by microglia cells by inhibiting NF-κB. This anti-inflammatory effect on microglia may be a potential mechanism for the neuroprotective effect of 4ae in VaD.


Asunto(s)
Demencia Vascular , Microglía , Animales , Ratas
18.
Microb Pathog ; 49(6): 330-5, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20688146

RESUMEN

Previous studies from our laboratory demonstrated that mice treated with morphine pellets are sensitized to Salmonella enterica, serovar Typhimurium infection. However, the opioid receptor antagonist, naltrexone, only partially blocked the effect of morphine, raising the possibility that the opioid might have some of its effects through a nonopioid receptor. To further clarify whether sensitization to infection is an opioid receptor-dependent phenomenon, µ-opioid receptor knockout (MORKO) mice were used in the present study. Wild-type (WT) and MORKO mice were treated with morphine and their sensitivity to oral Salmonella infection was assessed by mortality, bacterial burdens in gut associated lymphoid tissue and in blood and peritoneal fluid, and by levels of pro-inflammatory cytokines in plasma. MORKO animals treated with morphine were refractory to a sublethal dose of Salmonella, while similar treatment of WT animals resulted in 100% mortality. WT animals treated with morphine had high bacterial loads in all organs tested, while morphine-treated MORKO animals had no culturable Salmonella in any organs. Pro-inflammatory cytokine levels were elevated in morphine-treated WT but not MORKO mice infected with Salmonella. These results provide definitive evidence that the morphine-mediated enhancement of oral Salmonella infection is dependent on the µ-opioid receptor.


Asunto(s)
Susceptibilidad a Enfermedades/inducido químicamente , Morfina/toxicidad , Receptores Opioides mu/efectos de los fármacos , Salmonelosis Animal/microbiología , Salmonella typhimurium/patogenicidad , Animales , Líquido Ascítico/microbiología , Carga Bacteriana , Sangre/microbiología , Citocinas/sangre , Modelos Animales de Enfermedad , Femenino , Tejido Linfoide/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Opioides mu/deficiencia , Análisis de Supervivencia
19.
Chem Senses ; 35(6): 501-9, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20457570

RESUMEN

A healthy taste system is important to the maintenance of nutrition and overall quality of life, and taste disorders are associated with many inflammatory states. We previously determined the immune cells in normal human gustatory tissue; they are predominantly dendritic cells and CD4 T cells with a few macrophages and B lymphocytes present. There are, however, few reports of the subtypes of resident lymphocytes in or near taste tissues. The present study further characterized the distribution and population of the major subtypes of T cells in situ within biopsies of healthy human fungiform papillae (FP). Immunohistochemical analyses indicated that T-helper (Th)1 cells (CCR5+) were more predominant in FP than Th2 T cells (CCR4+). CD45RO+ memory T cells were the principal T cells in gustatory tissue, whereas CD45RA+ naive T cells were uncommon. Regarding subcompartments of the tissue, most intraepithelial lymphocytes of FPs were gamma/delta T cells, whereas the major subtype of lymphocytes in the lamina propria were alpha/beta T cells. Regulatory T cells that express CTLA-4 (CD152) and interleukin-2 receptors (IL-2R, CD25) were found at low levels in FP. The T cells stand ready to respond to inflammatory and infectious insults and may play a role in the taste alterations observed during acute and chronic inflammatory states.


Asunto(s)
Memoria Inmunológica , Subgrupos de Linfocitos T/inmunología , Papilas Gustativas/inmunología , Células TH1/inmunología , Adulto , Antígenos CD/metabolismo , Antígeno CTLA-4 , Femenino , Humanos , Inmunohistoquímica , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Antígenos Comunes de Leucocito/metabolismo , Masculino , Receptores CCR4/metabolismo , Receptores CCR5/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células TH1/metabolismo , Células Th2/inmunología , Células Th2/metabolismo , Lengua/citología
20.
Indian J Exp Biol ; 48(6): 554-8, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20882756

RESUMEN

Anti-bone resorption activity of pilose antler blood (Cervus nippon Temminck) were evaluated in ovariectomized Wistar rats. The rats were randomly divided into sham operated group (SHAM), ovariectomized group (OVX) and pilose antler blood treated group. The ovariectomized rats were treated with pilose antler blood orally in 4000 microl/kg daily doses for 10 weeks. Compared with SHAM group, serum 17 beta-estradiol level decreased significantly and osteocalcin level increased significantly in OVX group, indicating successful model of osteoporosis. The experiments showed that the bone mineral density of the lumbar spine and left femur in OVX group decreased remarkably compared to SHAM group but normalized by treatment with pilose antler blood. Additionally, serum levels of insulin-like growth factor-land testosterone were lower obviously in OVX group than those in SHAM group but preserved by pilose antler blood treatment. However, no obvious changes in serum levels of calcium, phosphorus, total alkaline phosphatase and osteoprotegerin were observed among three groups. These results suggested that administration of pilose antler blood was effective in alleviating osteoporosis in ovariectomized rats.


Asunto(s)
Cuernos de Venado/química , Resorción Ósea/tratamiento farmacológico , Materia Medica/farmacología , Osteoporosis/tratamiento farmacológico , Ovariectomía , Fosfatasa Alcalina/sangre , Animales , Peso Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Calcio/sangre , Estradiol/sangre , Femenino , Masculino , Materia Medica/aislamiento & purificación , Osteocalcina/sangre , Fósforo/sangre , Ratas , Ratas Wistar
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