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1.
Opt Express ; 31(17): 27520-27528, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710825

RESUMO

In recent years, microsphere-assisted microscopy (MAM) and atomic force microscope (AFM) have been rapidly developed to meet the measurement needs of microstructures. However, the positioning of microspheres, the inability of AFM to touch the underlying sample through the transparent insulating layer, and the challenge of AFM fast positioning limit their use in practical measurements. In this paper, we propose a method that combines MAM with AFM by adhering the microsphere to the cantilever. This method allows MAM and AFM to work in parallel, and their imaging positions can correspond with each other. We use this method to measure memory devices, and the results show that MAM and AFM yield complementary advantages. This approach provides a new tool for analyzing complex structures in devices and has potential for wide application.

2.
Opt Express ; 30(22): 39417-39430, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298895

RESUMO

In the past decade, microsphere-assisted nanoscopy has been developed rapidly to overcome the diffraction limit. However, due to the limited size and high surface curvature of microspheres, the magnified imaging still suffers from problems like limited view scope, imaging distortion, and low contrast. In this paper, we specialize in the imaging mechanism of microspheres and find irradiance as the key factor for microsphere imaging quality. Utilizing a modified optical tweezer system, we achieve precise manipulation of microspheres and further propose a high-quality large-field magnified imaging scheme. The results show that the imaging area of 5 µm microspheres can reach 16×12 µm2 with the minimum identifiable feature of 137 nm. This scheme provides a new solution for extending the measuring scope of microsphere-assisted nanoscope, and will certainly promote the application of this technology in practice.


Assuntos
Diagnóstico por Imagem , Pinças Ópticas , Microesferas
3.
Adv Neural Inf Process Syst ; 34: 3874-3886, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35664437

RESUMO

Associative memories in the brain receive and store patterns of activity registered by the sensory neurons, and are able to retrieve them when necessary. Due to their importance in human intelligence, computational models of associative memories have been developed for several decades now. In this paper, we present a novel neural model for realizing associative memories, which is based on a hierarchical generative network that receives external stimuli via sensory neurons. It is trained using predictive coding, an error-based learning algorithm inspired by information processing in the cortex. To test the model's capabilities, we perform multiple retrieval experiments from both corrupted and incomplete data points. In an extensive comparison, we show that this new model outperforms in retrieval accuracy and robustness popular associative memory models, such as autoencoders trained via backpropagation, and modern Hopfield networks. In particular, in completing partial data points, our model achieves remarkable results on natural image datasets, such as ImageNet, with a surprisingly high accuracy, even when only a tiny fraction of pixels of the original images is presented. Our model provides a plausible framework to study learning and retrieval of memories in the brain, as it closely mimics the behavior of the hippocampus as a memory index and generative model.

4.
Front Immunol ; 11: 574721, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33224140

RESUMO

Aquaculture production of crustaceans (mainly shrimp and crabs) has expanded globally, but disease outbreaks and pathogenic infections have hampered production in the last two decades. As invertebrates, crustaceans lack an adaptive immune system and mainly defend and protect themselves using their innate immune system. The immune system derives energy and metabolites from nutrients, with amino acids constituting one such source. A growing number of studies have shown that amino acids and their metabolites are involved in the activation, synthesis, proliferation, and differentiation of immune cells, as well as in the activation of immune related signaling pathways, reduction of inflammatory response and regulation of oxidative stress. Key enzymes in amino acid metabolism have also been implicated in the regulation of the immune system. Here, we reviewed the role played by amino acids and their metabolites in immune-modulation in crustaceans. Information is inferred from mammals and fish where none exists for crustaceans. Research themes are identified and the relevant research gaps highlighted for further studies.


Assuntos
Aminoácidos/imunologia , Crustáceos/imunologia , Sistema Imunitário/imunologia , Imunidade Inata , Aminoácidos/metabolismo , Animais , Crustáceos/metabolismo , Sistema Imunitário/metabolismo , Transdução de Sinais , Especificidade da Espécie
5.
Dev Comp Immunol ; 113: 103778, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32710907

RESUMO

Several researches reported that piscidin members of teleosts owned strong antiparasitic activity. Cryptocaryon irritans, a type of ectoparasite, could infect most of the marine teleosts. Larimichthys crocea could severely suffer from marine white spot disease caused by C. irritans, and their mortality rate was significantly high. Concentrating on this problem, we have done many related works. Piscidin 5 like (termed Lc-P5L) was another piscidin member isolated from a comparative transcriptome of C. irritans-immuned L. crocea. In the paper, quantitative Real-time PCR (qRT-PCR) showed Lc-P5L was upregulated in examined tissues, including gill, head kidney, muscle, liver, spleen and intestine after challenged by C. irritans, the significant upregulation time was in accordance to key developmental stages of C. irritans, which implied different infection stages could result in host immune response. Furthermore, using microscope techniques, we observed theronts or trophonts became weakly motile, cilia became detached, cells were out of shape, membranes eventually lysed in different cell positions and cytoplasmic contents leaked. Laser confocal scanning microscope (LCSM) observed theronts macronucleus grew swell and depolymerized after treated by recombinant Lc-P5L (rLc-P5L). Data suggested rLc-P5L was significantly lethal to C. irritans, and the death state of the parasite incubated with rLc-P5L was remarkably similar to other piscidin members or other antiparasitic peptides (APPs). Thus, these data provided new insights into L. crocea immunity against C. irritans and potential of rLc-P5L as a therapeutic agent against pathogen invasion.


Assuntos
Antiparasitários/farmacologia , Infecções por Cilióforos/imunologia , Cilióforos/efeitos dos fármacos , Cilióforos/fisiologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/farmacologia , Perciformes/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antiparasitários/metabolismo , Citotoxicidade Imunológica , Resistência à Doença/genética , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/genética , Estágios do Ciclo de Vida , Microscopia Confocal , Transcriptoma
6.
Fish Shellfish Immunol ; 100: 397-406, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32201349

RESUMO

Hemocyanin is a multifunctional respiratory glycoprotein, which has also been implicated in other biological functions in shrimp. Moreover, recent studies have revealed that hemocyanin is also involved in a broad range of immune-related activities in shrimp. However, in spite of the considerable interest in unraveling the reasons behind the multiple immune-related functions of hemocyanin, little is known about its transcriptional regulation. Here, DNA pull-down and Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS) analyses were used to isolate and identify the putative transcription factor(s) that are involved in the transcriptional regulation of the small subunit hemocyanin gene of Penaeus vannamei (PvHMCs). Krüppel-like factor (designated PvKruppel), a zinc finger transcription factor homolog in P. vannamei, was identified among the putative transcription factors, while bioinformatics analysis revealed the presence of Krüppel-like factor binding site (KLF motif) on the core promoter region of PvHMCs. Mutational analysis and electrophoretic mobility shift assay (EMSA) confirmed that PvKruppel could bind to the KLF motif on the core promoter region of PvHMCs. Moreover, in response to lipopolysaccharide (LPS), Vibrio parahaemolyticus and white spot syndrome virus (WSSV) challenge, transcript levels of PvKruppel and PvHMCs were negatively correlated. Furthermore, overexpression of PvKruppel significantly reduced the promoter activity of PvHMCs, while PvKruppel knockdown by RNA interference or lipopolysaccharides (LPS) stimulation resulted in a significant increase in the transcript level of PvHMCs. Taken together, our present study provides mechanistic insights into the transcriptional regulation of PvHMCs by PvKruppel during shrimp immune response to pathogens.


Assuntos
Proteínas de Artrópodes/genética , Hemocianinas/genética , Fatores de Transcrição Kruppel-Like/genética , Penaeidae/genética , Penaeidae/imunologia , Vibrioses/veterinária , Animais , Proteínas de Artrópodes/imunologia , Cromatografia Líquida , Regulação da Expressão Gênica , Hemocianinas/imunologia , Interações Hospedeiro-Patógeno , Fatores de Transcrição Kruppel-Like/imunologia , Espectrometria de Massas em Tandem , Transcrição Gênica , Vibrioses/imunologia , Vibrio parahaemolyticus/patogenicidade
7.
Dev Comp Immunol ; 107: 103642, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32061940

RESUMO

The respiratory glycoprotein, hemocyanin (HMC) has multiple immune-related functions, including antiviral activity. In this study, in silico methods were used to predict seven miRNAs targeting Litopenaeus vannamei HMC (LvHMC), out of which miR-589-5p was selected for further investigation because of its role in immune response. Transcript levels of miR-589-5p were ubiquitously distributed in all shrimp tissues examined, and significantly induced in hemocytes and hepatopancreas upon challenge with white-spot syndrome virus (WSSV) as well as by marine bacterial pathogens, which suggest that miR-589-5p is involved in shrimp immune response to pathogens. Morever, using Drosophila S2 cells stably overexpressing EGFP-LvHMC, flow cytometry and dual luciferase reporter assays, miR-589-5p was shown to significantly inhibit the in vitro expression of LvHMC. In addition, in vivo knockdown of miR-589-5p using antagomir-589-5p resulted in significant down-regulation in LvHMC expression, while overexpression of miR-589-5p using agomir-589-5p decreased the level of LvHMC expression in shrimp hemocytes and hepatopancreas. Further, the increased expression of miR-589-5p resulted in high shrimp mortality following WSSV challenge, coupled with an increase in the number of WSSV copies in hemocytes and hepatopancreas. These results suggest that miR-589-5p is involved in shrimp immune response to WSSV by negatively regulating the expression of LvHMC.


Assuntos
Proteínas de Artrópodes/metabolismo , Infecções por Vírus de DNA/imunologia , Hemocianinas/metabolismo , Hemócitos/fisiologia , MicroRNAs/genética , Penaeidae/imunologia , Vírus da Síndrome da Mancha Branca 1/fisiologia , Animais , Proteínas de Artrópodes/genética , Linhagem Celular , Drosophila , Regulação da Expressão Gênica , Hemocianinas/genética , Hepatopâncreas , Imunidade Inata/genética
8.
Chem Commun (Camb) ; 55(16): 2364-2367, 2019 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-30724917

RESUMO

The anions in electrolytes are the carriers of lithium ions for lithium-organic redox flow batteries. Herein, we reported that the interactions between the electrolyte anions and electron-deficient redox-active organic molecules (anion-π interactions) have strong influences on the battery properties due to the anion-π-induced formation of radical anions or sandwich-like aggregates.

9.
Chem Commun (Camb) ; 54(84): 11941-11944, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30288505

RESUMO

A super-π-acidic nanosized polycyclic aromatic hydrocarbon with six imide groups at the corners was prepared from the pre-synthesized 7,8-dichlorobenzo[ghi]perylenetriimide through a combination reaction of Ullmann-type and C-H transformation, which exhibited enhanced anion-π interactions with various anions.

10.
Fish Shellfish Immunol ; 75: 109-114, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29408708

RESUMO

Larimichthys crocea, the special marine economy fish, owns the largest annual yield for a single species in China. One of the most significant factors affecting large yellow croaker culture is the diseases, especially the threat of marine white spot disease which caused by a protozoan Cryptocaryon irritans. Antimicrobial peptides (AMPs) have been demonstrated to be active against bacterium, fungi and parasites, showing their potential usefulness in aquaculture as substitutes for antibiotics. Many researches have been carried out about the AMPs concentrating on the activity resist on C. irritans, and piscidin-like of L. crocea owning widely antibacterial spectrum and strong activity against C. irritans was screened in our team. In the paper, taking advantage of the large yellow croaker hepatic comparison transcriptome in response to C. irritans at 3d post infection, seven kinds of AMPs have been excavated from the differently expressed genes, including LEAP2 like, LEAP-2A, hepcidin, hepcidin-like, piscidin-5-like, piscidin-5-like type 4 and bactericidal permeability increasing protein (BPI). Hepcidin, hepcidin-like, piscidin-5-like, piscidin-5-like type4 and BPI were up-regulated to protect large yellow croaker from being damaged by C. irritans infection; while LEAP2 like and LEAP-2A were down-regulated, they might be as a negative-feedback regulation factor or some other regulatory mechanisms to adjust the immune response in the process of C. irritans infection. The differential expression changes were verified with quantitative real-time PCR (qRT-PCR) to illustrate the reliability of the sequenced data. Hearteningly, piscidin-5-like type 4 was a novel type which was high similar to other piscidin-5-like types. Interestingly, the infection may well cause alternative splicing of LEAP-2A mRNA, which was a surprised phenomenon and finding after C. irritans infection, but more further study was needed to be conducted. Therefore, the data showed that these AMPs were involved in the immune response to the C. irritans infection. In all, these results implied that the immune response of AMPs to C. irritans infection was a complex and sophisticated regulatory process.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/imunologia , Doenças dos Peixes/imunologia , Imunidade Inata , Perciformes/genética , Perciformes/imunologia , Transcriptoma , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
11.
Chemistry ; 23(65): 16612-16620, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-28967155

RESUMO

The search for high-performance electrode materials in organic rechargeable batteries remains a key challenge. Reported herein is a molecular structural modification of perylene imides, a promising class of redox-active electrode materials, for improved battery performance. The Diels-Alder extension of perylene imides at the lateral position led to the simultaneous incorporation of two electron-withdrawing carbonyl groups and extension of the π system, which is supposed to favor high specific capacity, operating voltage, and electronic conductivity. After the chiral dimerization of the extended species with 1,2-diaminocyclohexane, it was anticipated that the porosity and coulombic interactions with lithium ions would be promoted, which would be beneficial for fast reaction kinetics and long cycling life. As expected, in lithium batteries, the obtained chiral and π-extended tweezer, which features six imide groups and a porous solid-state network of 42.2 % accessible cell volume, was found to deliver a reversible capacity of 92.1 mA h g-1 at a charge/discharge rate of 1 C within an operating voltage window of 1.60-2.80 V versus Li+ /Li, around 75 and 50 % of which was maintained after 100 and 300 galvanostatic cycles, respectively, much better than those of unmodified species.

12.
Dalton Trans ; 44(2): 653-8, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25385547

RESUMO

Interpenetration is an intrinsic behaviour for the porous coordination networks. To prevent the interpenetration, a common strategy is the imposition of geometric or steric restrictions by incorporating bulky moieties into organic tectons. So far, most of the available incorporations have been achieved through a covalent connection, while few involved in the non-covalent weak interactions. In this paper, we have reported that such interpenetration can be prevented by the less common lone pair-π interactions. By imposing the lone pair-π interactions through the addition of lone-pair-bearing N-methylpyrrolidin-2-one or iodine, combinations of rigid naphthalene diimide tectons bearing two divergently oriented pyridyl units at both imide extremities with ZnSiF6 led to non-interpenetrated cuboid 3-D coordination networks that should have been interpenetrated. In addition, such close-contacting lone pair-π interactions between electron donors and acceptors have also been demonstrated to play a key role in their photochromic properties.

13.
Chin J Integr Med ; 21(3): 217-22, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25078360

RESUMO

OBJECTIVE: To analyze the diagnostic consistency of Chinese medicine (CM) specialists in patients with cardiovascular disease and to study syndrome classification and identification based on the multi-label learning method. METHODS: Using self-developed CM clinical scales to collect cases, inquiry information, complexity, tongue manifestation and pulse manifestation were assessed. The number of cases collected was 2,218. Firstly, each case was differentiated by two CM specialists according to the same diagnostic criteria. The consistency of the diagnosis based on Cohen's Kappa coefficient was analyzed. Secondly, take the same diagnosis syndromes of two specialists as the results of the cases. According to injury information in the CM scale "yes" or "no" was assigned "1" or "0", and according to the syndrome type in each case "yes" or "no" was assigned "1" or "0". CM information data on cardiovascular disease cases were established. We studied CM syndrome classification and identification based on the relevant feature for each label (REAL) learning method, and the diagnostic rate of the syndrome was studied using the REAL method when the number of features selected was 5, 10, 15, 20, 30, 50, 70, and 100, respectively. RESULTS: The syndromes with good diagnostic consistency were Heart (Xin)-qi deficiency, Heart-yang deficiency, Heart-yin deficiency, phlegm, stagnation of blood and stagnation of qi. Syndromes with poor diagnostic consistency were heart-blood deficiency and blood deficiency of Heart and Liver (Gan). The highest diagnostic rates using the REAL method were Heart-yang deficiency followed by Heart-qi deficiency. A different number of features, such as 5, 10, 15, 20, 30, 40, 50, 70, and 100, respectively, were selected and the diagnostic accuracy based on five features showed the highest diagnostic accuracy. The top five features which had a strong correlation with the syndromes were in accordance with the CM theory. CONCLUSIONS: CM syndrome differentiation is strongly subjective and it is difficult to obtain good diagnostic consistency. The REAL method fully considers the relationship between syndrome types and injury symptoms, and is suitable for the establishment of models for CM syndrome classification and identification. This method can probably provide the prerequisite for objectivity and standardization of CM differentiation.


Assuntos
Doenças Cardiovasculares/diagnóstico , Medicina Tradicional Chinesa/métodos , Especialização , Humanos , Modelos Teóricos , Síndrome
14.
Dalton Trans ; 43(48): 17908-11, 2014 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-25337900

RESUMO

Metal-ion-directed assembly of naphthalene diimide tectons cooperatively enhanced by anion-π interactions of giant anions, PMo12O40(3-), leads to a novel organic-inorganic hybrid with ultrafast-responsive photochromic properties, which is attributed to the polyoxometalate-sensitized photo-induced radical generation of naphthalene diimide units.

15.
Artigo em Chinês | MEDLINE | ID: mdl-21485176

RESUMO

The ensemble empirical mode decomposition (EEMD) can be used to overcome the mode mixing problem of empirical mode decomposition (EMD) effectively. The EEMD method and Hilbert-Huang Transform (HHT) can be used to analyze pulse signals of Traditional Chinese Medicine (TCM). The amplitudes of the added white noise were about 0.1 and 0.2 time standard deviation of the investigated signal respectively. The difference of average frequency and average energy of every mode between normal pulse, slippery pulse, wiry pulse and wiry-slippery pulse were demonstrated based on different amplitudes of the added white noise. The results showed that it is more in line with clinical practice when the amplitude of the added white noise is about 0.2 time standard deviation of the investigated signal.


Assuntos
Algoritmos , Medicina Tradicional Chinesa/métodos , Pulso Arterial , Processamento de Sinais Assistido por Computador , Artefatos , Diagnóstico Diferencial , Humanos
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