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1.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2575-2584, 2024 May.
Artigo em Zh | MEDLINE | ID: mdl-38812158

RESUMO

Asari Radix et Rhizoma is a common drug for relieving exterior syndrome in clinics, but its toxicity limits its use. In this study, the mechanism of hepatic damage of Asari Radix et Rhizoma was studied by network pharmacology and metabolomics. The hepatic damage-related dataset, namely GSE54257 was downloaded from the GEO database. The Limma package was used to analyze the differentially expressed genes in the dataset GSE54257. Toxic components and target genes of Asari Radix et Rhizoma were screened by TCMSP, ECTM, and TOXNET. The hepatic damage target genes of Asari Radix et Rhizoma were obtained by mapping with the differentially expressed gene of GSE54257, and a PPI network was constructed. GO and KEGG enrichment analysis of target genes were performed, and a "miRNA-target gene-signal pathway" network was drawn with upstream miRNA information. Thirty rats were divided into a blank group, a high-dose Asari Radix et Rhizoma group, and a low-dose Asari Radix et Rhizoma group, which were administered once a day. After continuous administration for 28 days, liver function indexes and liver pathological changes were detected. Five liver tissue samples were randomly collected from the blank group and high-dose Asari Radix et Rhizoma group, and small molecule metabolites were analyzed by ultra-high performance liquid chromatography-mass spectrometry(UHPLC-MS). The orthogonal partial least squares-discriminant analysis(OPLS-DA) method was used to screen differential metabolites, and enrichment analysis, correlation analysis, and cluster analysis were conducted for differential metabolites. Finally, the MetaboAnalyst platform was used to conduct pathway enrichment analysis for differential metabolites. It was found that there were 14 toxic components in Asari Radix et Rhizoma, corresponding to 37 target genes, and 12 genes related to liver toxicity of Asari Radix et Rhizoma were obtained by mapping to differentially expressed genes of GSE54257. The animal test results showed that Asari Radix et Rhizoma could significantly increase the liver function index, reduce the activity of the free radical scavenging enzyme, change the liver oxidative stress level, and induce lipid peroxidation damage in rats. The results of untargeted metabolomics analysis showed that compared with the blank group, nine metabolites were up-regulated, and 16 metabolites were down-regulated in the liver tissue of the Asari Radix et Rhizoma group. These 25 metabolites had strong correlations and good clustering. Pathway enrichment analysis showed that these differential metabolites and the 12 hepatotoxic target genes of Asari Radix et Rhizoma were mainly involved in purine metabolism, as well as the biosynthesis and metabolism of valine, leucine, glycine, serine, and threonine. The study confirmed that the hepatica damage effect of Asari Radix et Rhizoma was the result of multi-component, multi-target, and multi-signaling pathways, and its mechanism may be related to inhibiting nucleotide synthesis and affecting protein metabolism.


Assuntos
Medicamentos de Ervas Chinesas , Fígado , Metabolômica , Animais , Ratos , Medicamentos de Ervas Chinesas/administração & dosagem , Fígado/metabolismo , Fígado/efeitos dos fármacos , Masculino , Farmacologia em Rede , Ratos Sprague-Dawley , Asarum/química , Asarum/genética , Asarum/metabolismo , Rizoma/química , Humanos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/genética
2.
Langmuir ; 39(33): 11797-11806, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37555935

RESUMO

To improve the interfacial bonding of dissimilar composites, the interaction mechanism between the surface state and severe plastic deformation to strengthen the interfacial bonding strength was revealed. In this study, the different surface states of the steel strip were designed by louver blade grinding (LBG) and diamond bowl grinding (DBG), and the cold-rolled composite method was developed to prepare the brass/carbon steel composite strips. The results show that the steel surface after DBG has a large roughness of 9.79 µm, a hard hardening layer of 6.2 GPa, and high cleanliness of 1.34 atomic % oxygen content, while that after LBG has a roughness of 1.31 µm, a hardening layer of 4.2 GPa, and an oxygen content of 2.37 atomic %. The large roughness promotes the breaking of the hardening layer; the hardening layer is beneficial to obtain sufficient interfacial stress to expose the fresh metal; and the high cleanliness reduces the barrier to the fresh metal and contributes to the bonding of the fresh metal. The interface of the cold-rolled brass/carbon steel composite strip after LBG and DBG is mechanical bonding and metallurgical bonding, respectively. In the process of the cold-rolling composite, large shear deformation occurs at the interface of brass and steel, resulting in a high concentration of vacancy and dislocation defects, which provides a channel for interdiffusion of atoms at the interface. Under the diffusion driving force provided by the cold-rolling shear deformation heat, a nanodiffusion layer with a thickness of 60 nm and high interfacial bond strength was formed.

3.
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.

4.
Zhongguo Zhong Yao Za Zhi ; 46(4): 951-965, 2021 Feb.
Artigo em Zh | MEDLINE | ID: mdl-33645102

RESUMO

The Qinling-Daba Mountains area is the main producing areas of Gynostemma longipes for medicinal usage, and samples of wild whole plants in Pingli, Shaanxi Province and Qingchuan, Sichuan Province were collected. The ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF-MS~E) was used to profile the chemical compositions and analyze the similarities and differences of G. longipes samples in these areas. Based on the accurate molecular weight and fragment information obtained from Q-TOF-MS~E, the structures of the main components were identified by combining with the mass spectra, chromatographic behaviors of reference standards and related literatures. The results showed that the components of wild G. longipes from different places among Qinling-Daba Mountains area were similar. Forty-five chemical components were identified in the whole plant of G. longipes from Pingli, Shaanxi Province, including 43 triterpenoid saponins and 2 flavonoids which contain all main peaks in its fingerprint. The main components are dammarane-type triterpenoid saponins, such asgypenoside ⅩLⅨ, gypenoside A and its malonylated product of glycosyl.


Assuntos
Medicamentos de Ervas Chinesas , Saponinas , Cromatografia Líquida de Alta Pressão , Gynostemma , Espectrometria de Massas
5.
Pestic Biochem Physiol ; 164: 140-148, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32284120

RESUMO

Chelerythrine (CHE) possesses broad pharmacological activities. In this study, the extract of Chelidonium majus L. were characterized by high performance liquid chromatography (HPLC), infrared radiation (IR) spectroscopy and nuclear magnetic resonance (NMR). It was proved that the extract was CHE. The antifungal activity of CHE against five fungal pathogens of rice was researched in vitro, revealing that CHE inhibited Ustilaginoidea virens (U. virens) and Cochliobolus miyabeanus (C. miyabeanus) with 50% effective concentrations (EC50) of 6.53 × 10-3 mg/mL and 5.62 × 10-3 mg/mL, respectively. When the concentration of CHE was 7.5 × 10-3 mg/mL, the inhibition rate of U. virens reached 56.1%. Moreover, CHE (4 × 10-3 mg/mL) exhibited the greatest efficacy in inhibiting spore of U. virens growth with an inhibition rate as high as 86.7%. CHE displayed the best inhibitory activity against U. virens at the concentration of 7.5 × 10-3 mg/mL, compared with the other two isoquinoline alkaloids and commercial fungicide validamycin. After treating U. virens mycelia with CHE, twisted and atrophied mycelia were observed by optical microscopy. SEM results demonstrated narrow and locally fractured mycelium. TEM observations showed that the cell wall had become thin and broken, and most organelles were difficult to recognize. Furthermore, membrane of mycelia was destroyed and reactive oxygen species (ROS) of spores was accumulated, which induced apoptosis of pathogenic fungi. From these results, our understanding of the mechanisms of antifungal activity of CHE against U. virens was enriched and this research is relevant for developing novel pesticides.


Assuntos
Chelidonium , Oryza , Antifúngicos , Benzofenantridinas
6.
J Cell Biochem ; 120(3): 4238-4247, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30269353

RESUMO

OBJECTIVE: This study aimed to explore the effects of high-mobility group B1 (HMGB1) on coronary microembolization (CME)-induced myocardial inflammation, myocardial apoptosis, and cardiac function injury in rats. METHODS: Forty Sprague-Dawley rats were divided into sham operation group (sham group), microembolization group (CME group), CME + HMGB1 siRNA (HMGB1 siRNA) group, and CME + scrambled siRNA (control siRNA) group (10 rats in each group). The CME model group was constructed by injecting microembolism spheres into the apex of the left ventricle after clamping the ascending aorta. The sham group was constructed by injecting the same amount of saline. The HMGB1 siRNA group was injected with HMGB1 siRNA transfection complex via the tail vein 72 hours before CME modeling. The control siRNA group was injected with the same amount of scrambled siRNA mixture through the tail vein 72 hours before CME modeling. The cardiac function, serum cardiac troponin I level, and apoptotic index were examined 12 hours after the surgery. The levels of HMGB1, nuclear factor-κB (NF-κB) p65, glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), cleaved caspase-12, cleaved caspase-3, tumor necrosis factor-α (TNF-α), and interleukin 1ß (IL-1ß) were detected. RESULTS: Myocardial dysfunction, enhanced serum cardiac troponin I level, and apoptotic index were induced following CME. Moreover, CME increased the expression of HMGB1, NF-κB p65, GRP78, CHOP, cleaved caspase-12, cleaved caspase-3, TNF-α, and IL-1ß. HMGB1 siRNA reversed these effects, whereas scrambled siRNA had no effect. CONCLUSIONS: Inhibition of HMGB1 expression reduced CME-induced myocardial injury and improved cardiac function. Hence, it may serve as a new target for preventing and treating the CME-induced myocardial injury.


Assuntos
Vasos Coronários/patologia , Embolia/complicações , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Miocardite/etiologia , Miocardite/metabolismo , Animais , Apoptose/genética , Caspase 12/metabolismo , Caspase 3/metabolismo , Proteínas de Choque Térmico/metabolismo , Interleucina-1beta/metabolismo , Masculino , Miócitos Cardíacos/metabolismo , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley , Volume Sistólico/genética , Fator de Transcrição CHOP/metabolismo , Fator de Transcrição RelA/metabolismo , Transfecção , Troponina I/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
7.
Am J Transplant ; 19(9): 2421-2433, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30947382

RESUMO

Reactivation of latent cytomegalovirus remains an important complication after transplant. Although immunosuppression (IS) has been implicated as a primary cause, we have previously shown that the implantation response of a kidney allograft can lead to early transcriptional activation of latent murine cytomegalovirus (MCMV) genes in an immune-competent host and to MCMV reactivation and dissemination to other organs in a genetically immune-deficient recipient. We now describe a model that allows us to separately analyze the impact of the implantation effect vs that of a clinically relevant IS regimen. Treatment with IS of latently infected mice alone does not induce viral reactivation, but transplant of latently infected allogeneic kidneys combined with IS facilitates MCMV reactivation in the graft and dissemination to other organs. The IS regimen effectively dampens allo-immune inflammatory pathways and depletes recipient anti-MCMV but does not affect ischemia-reperfusion injury pathways. MCMV reactivation similar to that seen in allogeneic transplants combined with also occurs after syngeneic transplants. Thus, our data strongly suggest that while ischemia-reperfusion injury of the implanted graft is sufficient and necessary to initiate transcriptional reactivation of latent MCMV ("first hit"), IS is permissive to the first hit and facilitates dissemination to other organs ("second hit").


Assuntos
Infecções por Citomegalovirus/complicações , Transplante de Rim/efeitos adversos , Muromegalovirus/fisiologia , Insuficiência Renal/cirurgia , Ativação Viral , Animais , Modelos Animais de Doenças , Deleção de Genes , Histonas/metabolismo , Terapia de Imunossupressão , Rim/patologia , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Complicações Pós-Operatórias/virologia , Proteômica , Insuficiência Renal/complicações , Traumatismo por Reperfusão , Transplante Homólogo
8.
J Gen Virol ; 100(12): 1680-1694, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31647403

RESUMO

CD34+ myeloid lineage progenitor cells are an important reservoir of latent human cytomegalovirus (HCMV), and differentiation to macrophages or dendritic cells (DCs) is known to cause reactivation of latent virus. Due to its species-specificity, murine models have been used to study mouse CMV (MCMV) latency and reactivation in vivo. While previous studies have shown that MCMV genomic DNA can be detected in the bone marrow (BM) of latently infected mice, the identity of these cells has not been defined. Therefore, we sought to identify and enrich for cellular sites of MCMV latency in the BM haematopoietic system, and to explore the potential for establishing an in vitro model for reactivation of latent MCMV. We studied the kinetics and cellular characteristics of acute infection and establishment of latency in the BM of mice. We found that while MCMV can infect a broad range of haematopoietic BM cells (BMCs), latent virus is only detectable in haematopoietic stem cells (HSCs), myeloid progenitor cells, monocytes and DC-enriched cell subsets. Using three separate approaches, MCMV reactivation was detected in association with differentiation into DC-enriched BMCs cultured in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) followed by lipopolysaccharide (LPS) treatment. In summary, we have defined the kinetics and cellular profile of MCMV infection followed by the natural establishment of latency in vivo in the mouse BM haematopoietic system, including the haematopoietic phenotypes of cells that are permissive to acute infection, establish and harbour detectable latent virus, and can be stimulated to reactivate following DC enrichment and differentiation, followed by treatment with LPS.


Assuntos
Células da Medula Óssea/virologia , Diferenciação Celular , Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Ativação Viral , Latência Viral , Animais , Biomarcadores , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/virologia , Interações Hospedeiro-Patógeno , Interleucina-4/farmacologia , Cinética , Camundongos , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo , Células Mieloides/virologia , Tropismo Viral , Replicação Viral
9.
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.

10.
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.

11.
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.

12.
J Gen Virol ; 97(4): 941-954, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26795571

RESUMO

Reactivation of latent human cytomegalovirus is a significant infectious complication of organ transplantation and current therapies target viral replication once reactivation of latent virus has already occurred. The specific molecular pathways that activate viral gene expression in response to transplantation are not well understood. Our studies aim to identify these factors, with the goal of developing novel therapies that prevent transcriptional reactivation in transplant recipients. Murine cytomegalovirus (MCMV) is a valuable model for studying latency and reactivation of CMV in vivo. We previously demonstrated that transplantation of MCMV-latently infected kidneys into allogeneic recipients induces reactivation of immediate early (IE) gene expression and epigenetic reprogramming of the major immediate early promoter (MIEP) within 48 h. We hypothesize that these events are mediated by activation of signalling pathways that lead to binding of transcription factors to the MIEP, including AP-1 and NF-κB. Here we show that transplantation induces rapid activation of several members of the AP-1 and NF-κB transcription factor family and we demonstrate that canonical NF-κB (p65/p50), the junD component of AP-1, and nucleosome remodelling complexes are recruited to the MIEP following transplantation. Proteomic analysis of recipient plasma and transcriptome analysis of kidney RNA identified five extracellular ligands, including TNF, IL-1ß, IL-18, CD40L and IL-6, and three intracellular signalling pathways associated with reactivation of IE gene expression. Identification of the factors that mediate activation of these signalling pathways may eventually lead to new therapies to prevent reactivation of CMV and its sequelae.


Assuntos
Infecções por Herpesviridae/genética , Proteínas Imediatamente Precoces/genética , Transplante de Rim , Muromegalovirus/genética , NF-kappa B/genética , Fator de Transcrição AP-1/genética , Ativação Viral , Animais , Ligante de CD40/genética , Ligante de CD40/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/patologia , Interações Hospedeiro-Patógeno , Proteínas Imediatamente Precoces/imunologia , Interleucina-18/genética , Interleucina-18/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Muromegalovirus/imunologia , NF-kappa B/imunologia , Nucleossomos/genética , Nucleossomos/imunologia , Regiões Promotoras Genéticas , Proteoma/genética , Proteoma/imunologia , Transdução de Sinais , Fator de Transcrição AP-1/imunologia , Transplante Homólogo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/imunologia , Latência Viral
13.
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.

14.
Tumour Biol ; 36(10): 8093-100, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25983002

RESUMO

A key hallmark of cancer cells is their altered metabolism, known as Warburg effect. Lactate dehydrogenase A (LDHA) executes the final step of aerobic glycolysis and has been reported to be involved in the tumor progression. However, the function of LDHA in prostate cancer has not been studied. In current study, we observed overexpression of LDHA in the clinical prostate cancer samples compared with benign prostate hyperplasia tissues as demonstrated by immunohistochemistry and real-time qPCR. Attenuated expression of LDHA by siRNA or inhibition of LDHA activities by FX11 inhibited cell proliferation, migration, invasion, and promoted cell apoptosis of PC-3 and DU145 cells. Mechanistically, decreased Warburg effect as demonstrated by reduced glucose consumption and lactate secretion and reduced expression of MMP-9, PLAU, and cathepsin B were found after LDHA knockdown or FX11 treatment in PC-3 and DU145 cells. Taken together, our study revealed the oncogenic role of LDHA in prostate cancer and suggested that LDHA might be a potential therapeutic target.


Assuntos
Apoptose , Movimento Celular , Proliferação de Células , L-Lactato Desidrogenase/antagonistas & inibidores , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , RNA Interferente Pequeno/genética , Western Blotting , Humanos , Técnicas Imunoenzimáticas , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5 , Masculino , Hiperplasia Prostática/enzimologia , Hiperplasia Prostática/genética , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
15.
J Opt Soc Am A Opt Image Sci Vis ; 32(6): 1084-91, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26367042

RESUMO

The performances of different thermal ghost imaging (GI) algorithms are compared in an experiment of computational GI using a digital micromirror device. Here we present a rather different evaluation criterion named receiver operating characteristic (ROC) analysis that serves as the performance of merit for the quantitative comparison. A ROC curve is created by plotting the true positive rate against the false positive rate at various threshold settings. Both theoretical analysis and experimental results demonstrate that the ROC curve and the area under the curve are better and more intuitive indicators of the performance of the GI, compared with conventional evaluation methods. Additionally, for examining gray-scale objects, the calculation of the volume under the ROC surface is analyzed and serves as a performance metric. Our scheme should attract general interest and open exciting prospects for ROC analysis in thermal GI.

16.
Opt Express ; 22(20): 24268-75, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25322001

RESUMO

We present a new technique to denoise ghost imaging (GI) in which conventional intensity correlation GI and an iteration process have been combined to give an accurate estimate of the actual noise affecting image quality. The blurring influence of the speckle areas in the beam is reduced in the iteration by setting a threshold. It is shown that with an appropriate choice of threshold value, the quality of the iterative GI reconstructed image is much better than that of differential GI for the same number of measurements. This denoising method thus offers a very effective approach to promote the implementation of GI in real applications.

17.
Opt Express ; 22(6): 7133-44, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24664061

RESUMO

Compressed sensing is a theory which can reconstruct an image almost perfectly with only a few measurements by finding its sparsest representation. However, the computation time consumed for large images may be a few hours or more. In this work, we both theoretically and experimentally demonstrate a method that combines the advantages of both adaptive computational ghost imaging and compressed sensing, which we call adaptive compressive ghost imaging, whereby both the reconstruction time and measurements required for any image size can be significantly reduced. The technique can be used to improve the performance of all computational ghost imaging protocols, especially when measuring ultra-weak or noisy signals, and can be extended to imaging applications at any wavelength.

18.
Opt Lett ; 39(8): 2314-7, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24978981

RESUMO

An experiment demonstrating lensless ghost imaging (GI) with sunlight has been performed. A narrow spectral line is first filtered out and its intensity correlation measured. With this true thermal light source, an object consisting of two holes is imaged. The realization of lensless GI with sunlight is a step forward toward the practical application of GI with ordinary daylight as the source of illumination.

19.
J Surg Res ; 187(2): 640-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24332550

RESUMO

BACKGROUND: Smad3 is a principal intracellular mediator of signaling for transforming growth factor ß, a cytokine involved in pleiotropic pathophysiological processes including inflammation and immunity. The function of Smad3 in regulating inducible nitric oxide synthase (iNOS) expression and septic shock has not been characterized. METHODS: Smad3(-/-) (referred hereafter as KO) and wild-type (WT) mice were injected intraperitoneally with lipopolysaccharide (LPS) to induce the septic hypotension. Mortality, blood pressure, and plasma levels of nitrite were measured. The iNOS messenger RNA and protein levels in lung, kidney, and spleen were also analyzed. RESULTS: Mice lacking functional Smad3 respond to LPS with greater mortality than their WT littermates. The high mortality of KO mice is accompanied by enhanced hypotension after intraperitoneal injection of LPS. Both KO and WT mice displayed an increase in plasma nitrite during the experimental period; however, LPS administration caused more dramatic changes in KO mice than WT mice. Likewise, the iNOS messenger RNA and protein levels in lung, kidney, and spleen were more strongly increased in KO mice than in WT mice after LPS administration. CONCLUSIONS: Defects in the Smad3 gene may increase susceptibility to the development of septic hypotension because of enhanced iNOS production.


Assuntos
Endotoxemia/metabolismo , Hipotensão/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Sepse/metabolismo , Proteína Smad3/genética , Animais , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Endotoxemia/induzido quimicamente , Endotoxemia/mortalidade , Feminino , Hipotensão/induzido quimicamente , Hipotensão/mortalidade , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Knockout , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/genética , RNA Mensageiro/metabolismo , Sepse/induzido quimicamente , Sepse/mortalidade , Proteína Smad3/deficiência
20.
Appl Opt ; 52(33): 7882-8, 2013 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-24513737

RESUMO

We present a protocol for the amplification and distribution of a one-time-pad cryptographic key over a point-to-multipoint optical network based on computational ghost imaging (GI) and compressed sensing (CS). It is shown experimentally that CS imaging can perform faster authentication and increase the key generation rate by an order of magnitude compared with the scheme using computational GI alone. The protocol is applicable for any number of legitimate user, thus, the scheme could be used in real intercity networks where high speed and high security are crucial.

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