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1.
Opt Express ; 31(4): 5547-5560, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823832

RESUMO

Image-free tracking methods based on single-pixel detectors (SPDs) can track a moving object at a very high frame rate, but they rarely can achieve simultaneous imaging of such an object. In this study, we propose a method for simultaneously obtaining the relative displacements and images of a translational object. Four binary Fourier patterns and two differential Hadamard patterns are used to modulate one frame of the object and then modulated light signals are obtained by SPD. The relative displacements and image of the moving object can be gradually obtained along with the detection. The proposed method does not require any prior knowledge of the object and its motion. The method has been verified by simulations and experiments, achieving a frame rate of 3332 Hz to acquire relative displacements of a translational object at a spatial resolution of 128 × 128 pixels using a 20000-Hz digital micro-mirror device. This proposed method can broaden the application of image-free tracking methods and obtain spatial information about moving objects.

2.
Int J Neuropsychopharmacol ; 26(9): 585-598, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37490542

RESUMO

BACKGROUND: Alzheimer disease (AD) and depression often cooccur, and inhibition of phosphodiesterase-4 (PDE4) has been shown to ameliorate neurodegenerative illness. Therefore, we explored whether PDE4 inhibitor rolipram might also improve the symptoms of comorbid AD and depression. METHODS: APP/PS1/tau mice (10 months old) were treated with or without daily i.p. injections of rolipram for 10 days. The animal groups were compared in behavioral tests related to learning, memory, anxiety, and depression. Neurochemical measures were conducted to explore the underlying mechanism of rolipram. RESULTS: Rolipram attenuated cognitive decline as well as anxiety- and depression-like behaviors. These benefits were attributed at least partly to the downregulation of amyloid-ß, Amyloid precursor protein (APP), and Presenilin 1 (PS1); lower tau phosphorylation; greater neuronal survival; and normalized glial cell function following rolipram treatment. In addition, rolipram upregulated B-cell lymphoma-2 (Bcl-2) and downregulated Bcl-2-associated X protein (Bax) to reduce apoptosis; it also downregulated interleukin-1ß, interleukin-6, and tumor necrosis factor-α to restrain neuroinflammation. Furthermore, rolipram increased cAMP, PKA, 26S proteasome, EPAC2, and phosphorylation of ERK1/2 while decreasing EPAC1. CONCLUSIONS: Rolipram may mitigate cognitive deficits and depression-like behavior by reducing amyloid-ß pathology, tau phosphorylation, neuroinflammation, and apoptosis. These effects may be mediated by stimulating cAMP/PKA/26S and cAMP/exchange protein directly activated by cAMP (EPAC)/ERK signaling pathways. This study suggests that PDE4 inhibitor rolipram can be an effective target for treatment of comorbid AD and depression.


Assuntos
Doença de Alzheimer , Inibidores da Fosfodiesterase 4 , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/farmacologia , Rolipram/farmacologia , Camundongos Transgênicos , Inibidores da Fosfodiesterase 4/farmacologia , Doenças Neuroinflamatórias , Presenilina-1/metabolismo , Presenilina-1/farmacologia , Depressão/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Transtornos da Memória/tratamento farmacológico , Apoptose , Modelos Animais de Doenças
3.
Cell Mol Biol (Noisy-le-grand) ; 69(13): 112-119, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38158679

RESUMO

We aimed to explore microRNA (miR)-320's impacts on learning and memory in mice with vascular cognitive impairment induced via cerebral ischemia. After establishment of a cerebral small vessel disease (CSVD) cognitive impairment model, application of corresponding treatment methods was in the model mice to inject miR-320 antagomir/agomir and their negative controls to the lateral ventricles: Test of the learning and memory abilities of mice was conducted; Detection of oxidative stress, inflammation, miR-320, Vascular endothelial growth factor (VEGF) and endostatin (ES) was implemented; Taking mouse hippocampal neuron cells was to detect the cell advancement. MiR-320 was elevated in the CSVD model; MiR-320 was negatively linked with the learning and memory abilities of mice; Repressing miR-320 was available to memorably elevate the learning and memory abilities of CSVD mice; Depressing miR-320 clearly drove CSVD mouse neovascular protein VEGF, but reduced inflammation, oxidative stress response and ES; Restraining miR-320 was available to contribute to mouse neuronal cell advancement. MiR-320 mitigates the learning and memory abilities of cerebral ischemia-induced vascular cognitive dysfunction mice to a certain extent.


Assuntos
Disfunção Cognitiva , MicroRNAs , Animais , Camundongos , Infarto Cerebral , Disfunção Cognitiva/genética , Inflamação/complicações , MicroRNAs/genética , MicroRNAs/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética
4.
Phys Chem Chem Phys ; 25(45): 31418-31430, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37962373

RESUMO

Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) plays a crucial role in inflammation and cell death, so it is a promising candidate for the treatment of autoimmune, inflammatory, neurodegenerative, and ischemic diseases. So far, there are no approved RIPK1 inhibitors available. In this study, four machine learning algorithms were employed (random forest, extra trees, extreme gradient boosting and light gradient boosting machine) to predict small molecule inhibitors of RIPK1. The statistical metrics revealed similar performance and demonstrated outstanding predictive capabilities in all four models. Molecular docking and clustering analysis were employed to confirm six compounds that are structurally distinct from existing RIPK1 inhibitors. Subsequent molecular dynamics simulations were performed to evaluate the binding ability of these compounds. Utilizing the Shapley additive explanation (SHAP) method, the 1855 bit has been identified as the most significant molecular fingerprint fragment. The findings propose that these six small molecules exhibit promising potential for targeting RIPK1 in associated diseases. Notably, the identification of Cpd-1 small molecule (ZINC000085897746) from the Musa acuminate highlights its natural product origin, warranting further attention and investigation.


Assuntos
Aprendizado de Máquina , Simulação de Dinâmica Molecular , Simulação de Acoplamento Molecular
5.
Lab Invest ; 102(7): 702-710, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35013530

RESUMO

Although there have been recent advances in the molecular pathology of ependymomas, little is known about the underlying molecular evolution during its development. Here, we assessed the clinical, pathological and molecular evolutionary process of ependymoma recurrence in a 9-year-old patient who had seven recurrences of supratentorial ependymoma and died from intracranial multiregional recurrences at the age of 19 years old. Whole-genome sequencing (WGS) of 7 tumor samples (1 primary and 6 subsequent recurrent tumors) was performed to elucidate the mutation landscape and identify potential driver mutations for tumor evolution. The genetic profiles of the seven tumor specimens showed significant heterogeneity and suggested a highly branched evolutionary pattern. The mutational signatures and chromothripsis changed with treatments. Strikingly, adhesion G protein-coupled receptor L3 (ADGRL3, also known as Latrophilins 3, LPNH3) was found to be consistently mutated during the entire disease process. However, Sanger sequencing of other 78 ependymoma patients who underwent surgery at our institution showed no genetic alteration of ADGRL3, as found in the present case. The mRNA levels of ADGRL3 were significantly lower in ependymomas (n = 36), as compared with normal brain tissue (n = 3). Grade III ependymomas had the lowest ADGRL3 expression. Moreover, ependymomas with lower mRNA level of ADGRL3 had shorter overall survival. Our findings, therefore, demonstrate a rare evolutionary process of ependymoma involving ADGRL3.


Assuntos
Ependimoma , Adulto , Criança , Ependimoma/genética , Ependimoma/patologia , Ependimoma/cirurgia , Humanos , Mutação , RNA Mensageiro , Receptores Acoplados a Proteínas G/genética , Adulto Jovem
6.
Opt Express ; 30(13): 22608-22623, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36224954

RESUMO

High-flux measurement characteristics of compressed sensing (CS) imaging causes the imaging system prone to be disturbed by quantization. To realize high-quality CS imaging with limited detector bits, an improved imaging method combining sparse measurements and multiple dithers is proposed to reduce the dynamic range of the measured signals and increase that of effective detection. Simulations and experiments show that compared with traditional CS imaging, the proposed system decreases reconstruction errors caused by quantization distortions and may reduce the required number of detector bits to 1. The effects of detector noise and system parameters are discussed to validate the feasibility and performance of this method.

7.
Fish Shellfish Immunol ; 131: 368-380, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36243272

RESUMO

Tripartite motif (TRIM) proteins comprise a large family of RING-type ubiquitin E3 ligases that regulate important biological processes. In this study, full-length MnTRIM32 cDNA was obtained from oriental river prawn Macrobrachium nipponense, and eight MnTRIM32 isoforms generated by alternative splicing were identified. The open reading frames of the eight MnTRIM32 isoforms were predicted to be separately composed of 402, 346, 347, 346, 414, 358, 359, and 358 amino acid residues. Protein structural analysis revealed that all MnTRIM32 isoforms contained a RING domain and a coiled coil region. MnTRIM32 was ubiquitously expressed in all tissues tested, with the highest expression in the hepatopancreas. The mRNA levels of MnTRIM32 in the gills, stomach, and intestine of prawns were found to undergo time-dependent enhancement following white spot syndrome virus (WSSV) stimulation. Double-stranded RNA interference studies revealed that MnTRIM32 silencing significantly downregulated the expression levels of interferon (IFN) regulatory factor MnIRF, IFN-like factor MnVago4, and tumor necrosis factor MnTNF. Furthermore, knockdown of MnTRIM32 in WSSV-challenged prawns increased the expression of VP28 and the number of WSSV copies, suggesting that MnTRIM32 plays a positive role in limiting WSSV infection. These findings provided strong evidence for the important role of MnTRIM32 in the antiviral innate immunity of M. nipponense.


Assuntos
Palaemonidae , Vírus da Síndrome da Mancha Branca 1 , Animais , Vírus da Síndrome da Mancha Branca 1/fisiologia , Regulação da Expressão Gênica , Imunidade Inata/genética , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Filogenia
8.
Chemistry ; 27(41): 10628-10636, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-33837576

RESUMO

Quick capacity loss due to the polysulfide shuttle effects and poor rate performance caused by low conductivity of sulfur have always been obstacles to the commercial application of lithium sulfur batteries. Herein, an in-situ doped hierarchical porous biochar materials with high electron-ion conductivity and adjustable three-dimensional (3D) macro-meso-micropore is prepared successfully. Due to its unique physical structure, the resulting material has a specific surface area of 2124.9 m2 g-1 and a cumulative pore volume of 1.19 cm3 g-1 . The presence of micropores can effectively physically adsorb polysulfides and mesopores ensure the accessibility of lithium ions and active sites and give the porous carbon material a high specific surface area. The large pores provide channels for the storage of electrolyte and the transmission of ions on the surface of the substrate. The combined effect of these three kinds of pores and the N doping formed in-situ can effectively promote the cycle and rate performance of the battery. Therefore, prepared cathode can still reach a reversible discharge capacity of 616 mAh g-1 at a rate of 5 C. After 400 charge-discharge cycles at 1 C, the reversible capacity is maintained at 510.0 mAh g-1 . This new strategy has provided a new approach to the research and industrial-scale production of adjustable hierarchical porous biochar materials.

9.
Molecules ; 26(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922589

RESUMO

In vitro experiments have indicated prebiotic activity of isomaltulose, which stimulates the growth of probiotics and the production of short chain fatty acids (SCFAs). However, the absence of in vivo trials undermines these results. This study aims to investigate the effect of isomaltulose on composition and functionality of gut microbiota in rats. Twelve Sprague-Dawley rats were divided into two groups: the IsoMTL group was given free access to water containing 10% isomaltulose (w/w), and the control group was treated with normal water for five weeks. Moreover, 16S rRNA sequencing showed that ingestion of isomaltulose increased the abundances of beneficial microbiota, such as Faecalibacterium and Phascolarctobacterium, and decreased levels of pathogens, including Shuttleworthia. Bacterial functional prediction showed that isomaltulose affected gut microbial functionalities, including secondary bile acid biosynthesis. Targeted metabolomics demonstrated that isomaltulose supplementation enhanced cholic acid concentration, and reduced levels of lithocholic acid, deoxycholic acid, dehydrocholic acid, and hyodeoxycholic acid. Moreover, the concentrations of propionate and butyrate were elevated in the rats administered with isomaltulose. This work suggests that isomaltulose modulates gut microbiota and the production of SCFAs and secondary bile acids in rats, which provides a scientific basis on the use of isomaltulose as a prebiotic.


Assuntos
Ácidos e Sais Biliares/metabolismo , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Isomaltose/análogos & derivados , Probióticos/farmacologia , Animais , Teste de Tolerância a Glucose , Isomaltose/farmacologia , Masculino , RNA Ribossômico 16S/metabolismo , Ratos , Ratos Sprague-Dawley
10.
Opt Express ; 27(21): 29838-29853, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684240

RESUMO

A single-pixel compressive imaging technique that uses differential modulation based on the transformation of discrete orthogonal Krawtchouk moments is proposed. In this method, two sets of Krawtchouk basis patterns are used to differentially modulate the light source, then the Krawtchouk moments of the target object are acquired from the light intensities measured by a single-pixel detector. The target image is reconstructed by applying an inverse Krawtchouk moment transform represented in the matrix form. The proposed technique is verified by both computational simulations and laboratory experiments. The results show that this technique can retrieve an image from compressive measurements and the real-time reconstruction. The background noise can be removed by the differential measurement to realize the excellent image quality. Moreover, the proposed technique is especially suitable for the single-pixel imaging application that requires the extraction of the characteristics at the region-of-interest.

11.
Opt Express ; 27(16): 22138-22146, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510507

RESUMO

Compressive sensing (CS) has been used in LiDAR systems utilizing one single-photon-counting avalanche diode. We demonstrate an unexpected grayscale inversed image of an object at an unchosen depth, which appears in the reconstruction of the infrared single-pixel LiDAR system due to the pile-up effect. A correction algorithm and the sparse measurement are proposed and experimentally verified to effectively reduce the photon pile-up influence, so that the negative images can be completely removed. The correction methods in this research can improve the accuracy and the flexibility of the single-pixel LiDAR systems employing detectors with a low maximum light count.

12.
Artigo em Inglês | MEDLINE | ID: mdl-30453089

RESUMO

Restenosis is a major problem after percutaneous coronary intervention (PCI) treatment. Inflammation is one of the major core mechanisms involved in the occurrence of restenosis, and plays an important role in intimal hyperplasia. Detoxification and activating blood circulation decoction (DABCD) is a traditional Chinese medicine that is used in the treatment and prevention of atherosclerotic and inflammatory diseases. Our previous studies demonstrated that DABCD-mediated cardioprotection involves anti-inflammatory mechanisms and could be developed as a novel drug for the treatment of vascular smooth muscle cell (VSMC) proliferation and aortic restenosis. A rat model of postoperative restenosis after PCI was generated by balloon injury to determine the protective effects and potential mechanisms of DABCD. The injured segments of aortae were collected on days 14 and 28 after the operation to observe the morphological changes in the vascular structure and measure the proportion of inflammatory factors in plasma and vascular tissues, as well as test the proliferative activity of VSMCs. The expression of related proteins, namely, Toll-like receptor (TLR) 4 and nuclear factor (NF)-κB, in the mechanistic study was clarified by western blot analysis. We tested the hypothesis that the cardioprotective effects of DABCD on aortic restenosis are associated with the inhibition of aortic intimal hyperplasia in this model. Our results showed that DABCD has protective effect on rat aortic restenosis and the anti-inflammatory mechanism of DABCD on balloon-induced restenosis in rat may be due to its ability to inhibit TLR4-mediated NF-κB signaling pathways. DABCD may be a potential therapeutic agent against restenosis.


Assuntos
Oclusão com Balão/efeitos adversos , Circulação Sanguínea/efeitos dos fármacos , Reestenose Coronária/fisiopatologia , Medicamentos de Ervas Chinesas/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Reestenose Coronária/etiologia , Reestenose Coronária/metabolismo , Reestenose Coronária/patologia , Citocinas/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Músculo Liso Vascular/patologia , Ratos , Ratos Sprague-Dawley
13.
Arch Womens Ment Health ; 22(2): 279-287, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29980903

RESUMO

Postpartum depression is a common complication of childbearing and up to 12 months postpartum. This study aimed to determine the prevalence of postpartum depressive mood (PDM) in China by performing a meta-analysis of published studies. Studies that reported the prevalence of PDM in China were identified by searching the PubMed, Embase, CNKI, and CQVIP databases. Three thousand, one hundred, and two articles were obtained, and after careful evaluation, 26 studies were finally included in the meta-analysis. The combined studies included a total of 7618 cases with 1621 cases of PDM. The studies were assessed on the basis of heterogeneity testing and the potential for publication bias. Stata software 11.0 was used to perform the meta-analysis. The random-effect model showed that the prevalence of PDM was 21% with a 95% confidence interval (CI) of 17-25%. PDM was the highest 0 to 1.5 months after delivery. PDM levels decreased to 10.4% (95% CI 9.7-11.1%, P < 0.001) after publication bias were corrected. Sensitivity analyses evaluated the stability of our results and showed no significant change when any single study was excluded. Subgroup analyses showed that region, instruments used, cut-off score, and time points for depression assessment were positively associated with PDM prevalence. The prevalence of PDM differed among regions, with South Central China and East China exhibiting the lowest prevalence. The prevalence was higher in regions with poor economic development, suggesting that more attention should be devoted to Southwest and North China and that the prevalence of PDM should be evaluated 0 to 1.5 months after delivery.


Assuntos
Depressão Pós-Parto/epidemiologia , Povo Asiático/psicologia , China/epidemiologia , Feminino , Humanos , Prevalência
14.
Sensors (Basel) ; 18(5)2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29751680

RESUMO

This paper reports an efficient method for sound extraction from high-speed light spot videos reconstructed from the coded light spot images captured with a low-speed camera based on compressive sensing, but at the expense of consuming time. The proposed method first gets the high-speed video of the light spot that is illuminated on the vibrating target caused by sound. Then the centroid of the light spot is used to recover the sound. Simulations of the proposed method are carried out and experimental results are demonstrated. The results show that high-speed videos with a frame rate of 2000 Hz can be reconstructed with a low-speed (100 Hz) charge-coupled device (CCD) camera, which is randomly modulated by a digital micro-mirror device (DMD) 20 times during each exposure time. This means a speed improvement of 20 times is achieved. The effects of synchronization between CCD image recording and DMD modulation, the optimal sampling patterns of DMD, and sound vibration amplitudes on the performance of the proposed method are evaluated. Using this compressive camera, speech (counting from one to four in Chinese) was recovered well. This has been confirmed by directly listening to the recovered sound, and the intelligibility value (0⁻1) that evaluated the similarity between them was 0.8185. Although we use this compressive camera for sound detection, we expect it to be useful in applications related to vibration and motion.

15.
J Gene Med ; 19(6-7)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28636766

RESUMO

BACKGROUND: Our previous genome-wide association study of IgA nephropathy (IgAN) in a Chinese Han population suggested that the TNFSF13 gene may be a novel susceptibility gene for IgAN. In the present study, we aimed to further evaluate the associations of single-nucleotide polymorphisms (SNPs) and expression level of the TNFSF13 gene with the risk and clinical parameters of IgAN. METHODS: Six candidate SNPs were selected for genotyping by Sequenom MassARRAY iPLEX in 1000 IgAN cases and 1000 controls. Unconditional logistic regression was used to calculate the odds ratio (OR) and 95% confidence interval (95% CI) with adjustment for age and sex. Serum APRIL (encoded by the TNFSF13 gene) level was detected by an enzyme-linked immunosorbent assay. RESULTS: We found that rs3803800 was significantly associated with the susceptibility of IgAN after Bonferroni correction [padditive  = 0.0009, OR (95% CI) = 1.25 (1.09-1.42); precessive  = 0.0006, OR (95% CI) = 1.54 (1.20-1.96)]; however, the association remained only in women after further sex-stratified analysis. Genotype-phenotype correlation analysis showed significant associations of rs3803800 with severe clinicopathological manifestations in IgAN patients after adjusting for age and sex, as well as the other two SNPs (rs4246413 and rs4968210) that were also associated with specific clinical phenotypes. Compared with healthy controls, serum APRIL levels were significantly higher in IgAN patients (p = 0.0001) and associated with severity of disease. CONCLUSIONS: The results of the present study indicate that the genetic variations and gene expression level of TNFSF13 are associated with the susceptibility and severity of IgAN in a Han Chinese population.


Assuntos
Glomerulonefrite por IGA/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Estudos de Casos e Controles , China , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Glomerulonefrite por IGA/fisiopatologia , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Fatores Sexuais
16.
Opt Express ; 25(4): 3286-3296, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28241544

RESUMO

We experimentally demonstrate that the sensitivity of photon-counting imaging can be improved by 2 orders of magnitude with the compressed sensing (CS) theory. The maximum sensitivity of CS imaging under the quantum limit, which is approximately 1 photon in each pixel during one measurement, is quantitatively obtained through theoretical derivation and proved experimentally. The influences of dark noise and shot noise on photon-counting imaging are also studied to confirm the fundamental constrains on the imaging sensitivity of different imaging methods, which can guide the effort for further enhancing the ultra-weak light imaging ability.

17.
Chembiochem ; 16(1): 100-9, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25404066

RESUMO

CalE6 is a previously uncharacterized protein involved in the biosynthesis of calicheamicins in Micromonospora echinospora. It is a pyridoxal-5'-phosphate-dependent enzyme and exhibits high sequence homology to cystathionine γ-lyases and cystathionine γ-synthases. However, it was found to be active towards methionine and to convert this amino acid into α-ketobutyrate, ammonium, and methanethiol. The crystal structure of the cofactor-bound holoenzyme was resolved at 2.0 Å; it contains two active site residues, Gly105 and Val322, specific for methionine γ-lyases. Modeling of methionine into the active site allows identification of the active site residues responsible for substrate recognition and catalysis. These findings support that CalE6 is a putative methionine γ-lyase producing methanethiol as a building block in biosynthesis of calicheamicins.


Assuntos
Proteínas de Bactérias/química , Liases de Carbono-Enxofre/química , Coenzimas/química , Holoenzimas/química , Micromonospora/enzimologia , Fosfato de Piridoxal/química , Sequência de Aminoácidos , Aminoglicosídeos/biossíntese , Compostos de Amônio/química , Compostos de Amônio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Butiratos/química , Butiratos/metabolismo , Carbono-Oxigênio Liases/química , Carbono-Oxigênio Liases/genética , Carbono-Oxigênio Liases/metabolismo , Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/metabolismo , Domínio Catalítico , Coenzimas/metabolismo , Cristalografia por Raios X , Enedi-Inos , Expressão Gênica , Holoenzimas/genética , Holoenzimas/metabolismo , Metionina/química , Metionina/metabolismo , Micromonospora/genética , Modelos Moleculares , Dados de Sequência Molecular , Família Multigênica , Fosfato de Piridoxal/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Compostos de Sulfidrila/química , Compostos de Sulfidrila/metabolismo
18.
Opt Express ; 23(26): 33802-11, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26832041

RESUMO

We present an experimental demonstration of edge detection based on ghost imaging (GI) in the gradient domain. Through modification of a random light field, gradient GI (GGI) can directly give the edge of an object without needing the original image. As edges of real objects are usually sparser than the original objects, the signal-to-noise ratio (SNR) of the edge detection result will be dramatically enhanced, especially for large-area, high-transmittance objects. In this study, we experimentally perform one- and two-dimensional edge detection with a double-slit based on GI and GGI. The use of GGI improves the SNR significantly in both cases. Gray-scale objects are also studied by the use of simulation. The special advantages of GI will make the edge detection based on GGI be valuable in real applications.

19.
J Org Chem ; 80(9): 4672-82, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25836059

RESUMO

Bidentate directing group (DG) strategy is a promising way to achieve sp(2) and more inert sp(3) C-H bond activations in transition metal (TM) catalysis. In this work, we systematically explored the assisting effects exerted by bidentate DGs in the C-H bond activations. Through DFT calculations and well-defined comparative analysis, we for the first time unified the rationale of the reactivity promoted by bidentate DG in sp(2) and sp(3) C-H activations, which are generally consistent with available experimental discoveries about the C-H activation reactivity up to date. In addition to the general rationale of the reactivity, the assisting effects of several typical bidentate DGs were also quantitatively evaluated and compared to reveal their relative promoting ability for C-H activation reactivity. Finally, the effect of the ligating group charge and the position of the ligating group charge in bidentate DGs were also investigated, based on which new types of DGs were designed and proposed to be potentially effective in C-H activation. The deeper understanding and new insight about the bidentate DG strategy gained in this work would help to enhance its further experimental development in sp(2) and sp(3) C-H bond activations.

20.
Bioorg Med Chem Lett ; 25(22): 5449-53, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26428871

RESUMO

Despite a potential application of PRMT1 inhibitors in cancer treatment, very few of PRMT1 inhibitors have been reported. To obtain novel potent PRMT1 inhibitors, structure optimizations towards a hit compound, 4-((6-chloro-5-nitropyrimidin-4-yl)amino)benzimidamide, were carried out. A series of 4-((5-nitropyrimidin-4-yl)amino)benzimidamide derivatives were synthesized. Structure-activity relationship analysis led to the discovery of a number of PRMT1 inhibitors. The most potent compound corresponds to compound 6d, which showed an IC50 value of 2.0 µM against PRMT1. This compound also displayed a considerable anti-proliferative activity against three tumor cell lines, DLD-1, T24 and SH-SY-5Y, with IC50 values of 4.4 µM, 13.1 µM and 11.4 µM, respectively.


Assuntos
Benzimidazóis/química , Benzimidazóis/farmacologia , Descoberta de Drogas , Modelos Biológicos , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Amidas/química , Amidas/farmacologia , Animais , Sítios de Ligação , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Nitrocompostos/química , Nitrocompostos/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Relação Estrutura-Atividade
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