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After 500 million years of evolution, lamprey is in a natural environment characterized by low temperature and high iron content, and its unique adaptive evolution mode has developed its organizational structure and life mechanism in the process of metamorphosis, which provides a new direction for people to further study the origin and evolution of life. Iron is one of the essential nutrients for the human body and plays an important role in metabolic processes, but when exceeded, it can lead to iron toxicity. For example, the serum iron concentration of pre-metamorphosis larvae is 149 times that of normal males, and the iron content in the liver of juveniles is about 2-3 times that of normal humans. Lamprey has a complete biochemical system to tolerate high concentrations of free iron in the body, and high expression of important genes for iron homeostasis, such as transferrin, ferritin heavy chain, superoxide dismutase, etc., improves iron transport, iron storage and antioxidant capacity. Lamprey has an IRE/IRP regulatory system, which is an important protection mechanism for lamprey to adapt to the high iron content environment in the organization. In addition, lampreys gradually form oral glands during metamorphosis and development, which become the unique iron metabolism organs of lampreys. In this review, we mainly summarize the distribution of iron in various tissues of lamprey and the potential mechanism of adapting to the content of iron in the body, so as to provide a theoretical basis for the subsequent search for the molecular mechanism of iron metabolism.
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Ferro , Lampreias , Animais , Ferro/metabolismo , Lampreias/metabolismo , Homeostase , HumanosRESUMO
Accumulated evidence has demonstrated causative links between neuropathic pain (NP) and immune-mediated inflammatory disorders. However, the role of inflammasome-induced pyroptosis in NP remains elusive. Melatonin possesses a well-documented analgesic action in various pain models. The current study aimed to test our hypothesis that melatonin regulated pyroptosis to alleviate NP by inhibiting NF-κB/NLRP3-dependent signaling. A rat model of spinal nerve ligation (SNL) was established to explore the potential association between melatonin and pyroptosis. Behavioral experiments revealed that SNL provoked severe allodynia which was suppressed by the administration of melatonin, a caspase-1 inhibitor (VX-765), or an NF-κB inhibitor (BAY 11-7085). SNL significantly up-regulated the inflammatory cytokines associated with the excessive activation of NLRP3 components and NF-κB signaling, as well as a marked pyroptosis activation. These effects were partially inhibited by melatonin, VX-765 or BAY 11-7085, and when melatonin and inhibitors were added together, the effect was enhanced. In conclusion, melatonin has potent analgesic and anti-inflammatory effects in SNL models through preventing pyroptosis via the NF-κB/NLRP3 inflammasome signaling pathway.
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Inflamassomos , Melatonina , Animais , Inflamassomos/metabolismo , Melatonina/farmacologia , Melatonina/uso terapêutico , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Ratos , Transdução de Sinais , Nervos Espinhais/metabolismoRESUMO
Digital cameras obtain color information of the scene using a chromatic filter, usually a Bayer filter, overlaid on a pixelated detector. However, the periodic arrangement of both the filter array and the detector array introduces frequency aliasing in sampling and color misregistration during demosaicking process which causes degradation of image quality. Inspired by the biological structure of the avian retinas, we developed a chromatic LED array which has a geometric arrangement of multi-hyperuniformity, which exhibits an irregularity on small-length scales but a quasi-uniformity on large scales, to suppress frequency aliasing and color misregistration in full color image retrieval. Experiments were performed with a single-pixel imaging system using the multi-hyperuniform chromatic LED array to provide structured illumination, and 208 fps frame rate was achieved at 32 × 32 pixel resolution. By comparing the experimental results with the images captured with a conventional digital camera, it has been demonstrated that the proposed imaging system forms images with less chromatic moiré patterns and color misregistration artifacts. The concept proposed verified here could provide insights for the design and the manufacturing of future bionic imaging sensors.
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Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Algoritmos , Biônica , Cor , ColorimetriaRESUMO
Single-pixel imaging techniques extend the time dimension to reconstruct a target scene in the spatial domain based on single-pixel detectors. Structured light illumination modulates the target scene by utilizing multi-pattern projection, and the reflected or transmitted light is measured by a single-pixel detector as total intensity. To reduce the imaging time and capture high-quality images with a single-pixel imaging technique, orthogonal patterns have been used instead of random patterns in recent years. The most representative among them are Hadamard patterns and Fourier sinusoidal patterns. Here, we present an alternative Fourier single-pixel imaging technique that can reconstruct high-quality images with an intensity correlation algorithm using acquired Fourier positive-negative images. We use the Fourier matrix to generate sinusoidal and phase-shifting sinusoid-modulated structural illumination patterns, which correspond to Fourier negative imaging and positive imaging, respectively. The proposed technique can obtain two centrosymmetric images in the intermediate imaging course. A high-quality image is reconstructed by applying intensity correlation to the negative and positive images for phase compensation. We performed simulations and experiments, which obtained high-quality images, demonstrating the feasibility of the methods. The proposed technique has the potential to image under sub-sampling conditions.
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Whereas modern digital cameras use a pixelated detector array to capture images, single-pixel imaging reconstructs images by sampling a scene with a series of masks and associating the knowledge of these masks with the corresponding intensity measured with a single-pixel detector. Though not performing as well as digital cameras in conventional visible imaging, single-pixel imaging has been demonstrated to be advantageous in unconventional applications, such as multi-wavelength imaging, terahertz imaging, X-ray imaging, and three-dimensional imaging. The developments and working principles of single-pixel imaging are reviewed, a mathematical interpretation is given, and the key elements are analyzed. The research works of three-dimensional single-pixel imaging and their potential applications are further reviewed and discussed.
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Single-pixel imaging uses a single-pixel detector, rather than a focal plane detector array, to image a scene. It provides advantages for applications such as multi-wavelength, three-dimensional imaging. However, low frame rates have been a major obstacle inhibiting the use of computational ghost imaging technique in wider applications since its invention one decade ago. To address this problem, a computational ghost imaging scheme, which utilizes an LED-based, high-speed illumination module is presented in this work. At 32 × 32 pixel resolution, the proof-of-principle system achieved continuous imaging with 1000 fps frame rate, approximately two orders larger than those of other existing ghost imaging systems. The proposed scheme provides a cost-effective and high-speed imaging technique for dynamic imaging applications.
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Digital cameras use detector arrays with regular geometry for optical sampling. Though regular arrangement was demonstrated to be optimal for two-dimensional sampling, it causes aliasing at high frequencies exceeding its Nyquist limit. Here, we proposed a randomization procedure to generate 2D hyperuniform patterns that can be used to suppress aliasing in image retrieval. Experiments are performed using a single-pixel camera, where the sampling patterns do not necessarily follow a fixed Cartesian geometry. Results demonstrate that the images reconstructed by hyperuniform patterns have a lower root mean squared error and exhibit less moiré fringes at high frequencies than the images reconstructed by regular square patterns do. Furthermore, the same conclusion can be applied to the production of conventional detector arrays, where manufacturing imperfection could be utilized to suppress frequency aliasing in image retrieval.
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Single-pixel cameras provide a means to perform imaging at wavelengths where pixelated detector arrays are expensive or limited. The image is reconstructed from measurements of the correlation between the scene and a series of masks. Although there has been much research in the field in recent years, the fact that the signal-to-noise ratio (SNR) scales poorly with increasing resolution has been one of the main limitations prohibiting the uptake of such systems. Microscanning is a technique that provides a final higher resolution image by combining multiple images of a lower resolution. Each of these low resolution images is subject to a sub-pixel sized lateral displacement. In this work we apply a digital microscanning approach to an infrared single-pixel camera. Our approach requires no additional hardware, but is achieved simply by using a modified set of masks. Compared to the conventional Hadamard based single-pixel imaging scheme, our proposed framework improves the SNR of reconstructed images by â¼ 50 % for the same acquisition time. In addition, this strategy also provides access to a stream of low-resolution 'preview' images throughout each high-resolution acquisition.
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The Hanbury Brown and Twiss (HBT) effect is a classical intensity correlation effect, but it is also widely used in the quantum optics regime, and has led to many important breakthroughs in both basic and applied physics, among which ghost imaging (GI) has aroused particular interest. In this article, the positive and negative intensity correlations in HBT correlation are analyzed, based on which we describe experiments on thermal light nonlocal imaging of a reflective object using the positive and negative correlations of correspondence imaging. An improvement of 16.3% in the signal-to-noise ratio of the reconstructed image has been achieved, indicating that this method may have promising potential in future GI applications where noise is a serious problem and smaller sampling numbers are necessary.
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Porcine epidemic diarrhea virus (PEDV) infection results in significant mortality among newborn piglets, leading to substantial economic setbacks in the pig industry. Short-chain fatty acids (SCFA), the metabolites of intestinal probiotics, play pivotal roles in modulating intestinal function, enhancing the intestinal barrier, and bolstering immune responses through diverse mechanisms. The protective potential of Lactobacillus delbrueckii, Lactobacillus johnsonii, and Lactococcus lactis was first noted when administered to PEDV-infected piglets. Histological evaluations, combined with immunofluorescence studies, indicated that piglets receiving L. lactis displayed less intestinal damage, with diminished epithelial cell necrosis and milder injury levels. Differences in immunofluorescence intensity revealed a significant disparity in antigen content between the L. lactis and PEDV groups, suggesting that L. lactis might suppress PEDV replication, the intestine. We then assessed short-chain fatty acid content through targeted metabolomics, finding that acetate levels markedly varied from other groups. This protective impact was confirmed by administering acetate to PEDV-infected piglets. Data suggested that piglets receiving acetate exhibited resistance to PEDV. Flow cytometry analyses were conducted to evaluate the expression of innate and adaptive immune cells in piglets. Sodium acetate appeared to bolster innate immune defenses against PEDV, marked by elevated NK cell and macrophage counts in mesenteric lymph nodes, along with increased NK cells in the spleen and macrophages in the bloodstream. Acetic acid was also found to enhance the populations of CD8+ IFN-γ T cells in the blood, spleen, and mesenteric lymph, CD4+ IFN-γ T cells in mesenteric lymph nodes and spleen, and CD4+ IL-4+T cells in the bloodstream. Transcriptome analyses were carried out on the jejunal mucosa from piglets with PEDV-induced intestinal damage and from healthy counterparts with intact barriers. Through bioinformatics analysis, we pinpointed 189 significantly upregulated genes and 333 downregulated ones, with the PI3K-AKT, ECM-receptor interaction, and pancreatic secretion pathways being notably enriched. This transcriptomic evidence was further corroborated by western blot and qPCR. Short-chain fatty acids (SCFA) were found to modulate G protein-coupled receptor 41 (GPR41) and 43 (GPR43) in porcine intestinal epithelial cells (IPEC-J2). Post-acetic acid exposure, there was a notable upsurge in the ZO-1 barrier protein expression in IPEC-J2 compared to the unexposed control group (WT), while GPR43 knockdown inversely affected ZO-1 expression. Acetic acid amplified the concentrations of phosphorylated PI3K and AKT pivotal components of the PI3K/AKT pathway. Concurrently, the co-administration of AKT agonist SC79 and PI3K inhibitor LY294002 revealed acetic acid's role in augmenting ZO-1 expression via the P13K/AKT signaling pathway. This study demonstrates that acetic acid produced by Lactobacillus strains regulates intestinal barrier and immune functions to alleviate PEDV infection. These findings provide valuable insights for mitigating the impact of PEDV in the pig industry.
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BACKGROUND: The gut microbiota is a critical factor in the regulation of host health, but the relationship between the differential resistance of hosts to pathogens and the interaction of gut microbes is not yet clear. Herein, we investigated the potential correlation between the gut microbiota of piglets and their disease resistance using single-cell transcriptomics, 16S amplicon sequencing, metagenomics, and untargeted metabolomics. RESULTS: Porcine epidemic diarrhea virus (PEDV) infection leads to significant changes in the gut microbiota of piglets. Notably, Landrace pigs lose their resistance quickly after being infected with PEDV, but transplanting the fecal microbiota of Min pigs to Landrace pigs alleviated the infection status. Macrogenomic and animal protection models identified Lactobacillus reuteri and Lactobacillus amylovorus in the gut microbiota as playing an anti-infective role. Moreover, metabolomic screening of the secondary bile acids' deoxycholic acid (DCA) and lithocholic acid (LCA) correlated significantly with Lactobacillus reuteri and Lactobacillus amylovorus, but only LCA exerted a protective function in the animal model. In addition, LCA supplementation altered the distribution of intestinal T-cell populations and resulted in significantly enriched CD8+ CTLs, and in vivo and in vitro experiments showed that LCA increased SLA-I expression in porcine intestinal epithelial cells via FXR receptors, thereby recruiting CD8+ CTLs to exert antiviral effects. CONCLUSIONS: Overall, our findings indicate that the diversity of gut microbiota influences the development of the disease, and manipulating Lactobacillus reuteri and Lactobacillus amylovorus, as well as LCA, represents a promising strategy to improve PEDV infection in piglets. Video Abstract.
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Infecções por Coronavirus , Microbioma Gastrointestinal , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Suínos , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Doenças dos Suínos/prevenção & controle , Resistência à DoençaRESUMO
OBJECTIVE: The mechanism of action of Sanhua Decoction (SHD) in the treatment of ischemic stroke (IS) was analyzed based on the network pharmacology technology, and the pharmacodynamics and key targets were verified using the rat middle cerebral artery occlusion (MCAO) model. METHODS: The GEO database was used to collect IS-related gene set S D , and DrugBank and TTD databases were used to obtain the therapeutic drug target set S T . IS disease gene set S I was collected from DisGeNET, GeneCards, and OMIM databases. These three different gene sets obtained from various sources were merged, duplicates were removed, and the resulting IS disease gene set S IS was imported into the STRING database to establish the protein-protein interaction (PPI) network. Two methods were used to screen the key targets of IS disease based on the PPI network analysis. The TCMSP database and PubChem were applied to retrieve the main chemical components of SHD, and the ACD/Labs software and the SwissADME online system were utilized for ADMET screening. HitPick, SEA, and SwissTarget Prediction online systems were used to predict the set of potential targets for SHD to treat IS. The predicted set of potential targets and the IS disease gene set were intersected. Subsequently, the set of potential targets for SHD treatment of IS was identified, the target information was confirmed through the UniProt database, and finally, the component-target data set for SHD treatment of IS was obtained. clusterProfiler was used for GO function annotation and KEGG pathway enrichment analysis on the target set of SHD active ingredients. A rat MCAO model was established to evaluate the pharmacodynamics of SHD in the treatment of IS, and Western blot analysis assessed the level of proteins in the related pathways. RESULTS: This study obtained 1,009 IS disease gene sets. PPI network analysis identified 12 key targets: AGT, SAA1, KNG1, APP, GNB3, C3, CXCR4, CXCL12, CXCL8, CXCL1, F2, and EDN1. Database analyses retrieved 40 active ingredients and 47 target genes in SHD. The network proximity algorithm was used to optimize the six key components in SHD. KEGG enrichment showed that the signaling pathways related to IS were endocrine resistance, estrogen, TNF signal pathway, and AGEs/RAGE. Compound-disease-target regulatory network analysis showed that AKT1, IL-6, TNF-α, TP53, VEGFA, and APP were related to the treatment of IS with SHD. Animal experiments demonstrated that SHD significantly reduces the neurological function of rat defect symptoms (P < 0.05), the area of cerebral avascular necrosis, and neuronal necrosis while increasing the levels of IL-6 and APP proteins (P < 0.05) and reducing the levels of AKT1 and VEGFA proteins (P < 0.05). CONCLUSION: The effective components of SHD may regulate multiple signaling pathways through IL-6, APP, AKT1, and VEGFA to reduce brain damage and inflammatory damage and exert a neuroprotective role in the treatment of IS diseases. Thus, this study provides a feasible method to study the pharmacological mechanism of traditional Chinese medicine compound prescriptions and a theoretical basis for the development of SHD into a new drug for IS treatment.
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Medicamentos de Ervas Chinesas , AVC Isquêmico , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Interleucina-6 , AVC Isquêmico/tratamento farmacológico , Medicina Tradicional Chinesa/métodos , Simulação de Acoplamento Molecular , Farmacologia em Rede , RatosRESUMO
The current study aimed to investigate the role and underlying mechanism of Resolvin D1 (RvD1) alleviating spinal nerve ligation (SNL)-induced neuropathic pain (NP) and its interplay with regulatory cascades of Nod-like Receptor Protein 3 (NLRP3) inflammasome. Sprague-Dawley male rat models of SNL-stimulated NP were established, which were pre-treated with different doses of RvD1, WRW4 (ALX/FPR2 inhibitor) or U0126 (ERK inhibitor) for three successive days following the operation. Pain behavior was assessed by measuring changes in the mechanical sensitivity of the hind paws during an observation period of seven consecutive days. The spinal cord (SC) and dorsal root ganglions (DRGs) tissues were collected on postoperative day 7. Immunohistochemistry (IHC) and Western blot were performed to determine the expression levels of NLRP3 inflammasome complex, ALX/FPR2 receptor and extracellular signal-related kinase (ERK). The pro-inflammatory mediators (IL-1ß and IL-18) were measured by enzyme-linked immunosorbent assay (ELISA). The results showed that RvD1 could alleviate mechanical allodynia significantly in the SNL-induced NP rat models. Also, RvD1 inhibited the expression of p-ERK, the NLRP3 inflammasomes complex and its corresponding downstream pro-inflammatory mediators which were significantly enhanced in the SC and DRGs of the rat SNL models. While these changes were partially reversed by pre-administration of WRW4 and further strengthened by co-treated with U0126. Our results suggest that RvD1 dependent on ALX/FPR2 may have an analgesic and anti-inflammatory influence on SNL-induced NP driven by inhibiting NLRP3 inflammasome via ERK signaling pathway. These data also provide strong support for the recent modulation of neuro-inflammatory priming and highlight the potential for specialized pro-resolving mediators (SPMs) as novel therapeutic avenues for NP.
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Ácidos Docosa-Hexaenoicos , Hiperalgesia , Neuralgia , Animais , Ácidos Docosa-Hexaenoicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hiperalgesia/tratamento farmacológico , Inflamassomos , Mediadores da Inflamação , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neuralgia/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Receptores de Lipoxinas/metabolismoRESUMO
Alcoholic liver disease (ALD) is a major worldwide chronic liver disease accompanied by hepatic inflammation, gut leakiness, and abnormal oxidative stress. Our previous study demonstrated substantial hepatoprotective activity of the active Poria cocos polysaccharide (PCP-1C). The present study explored whether PCP-1C protects against ALD among hepatic inflammation, gut leakiness, and abnormal oxidative stress. The results showed that PCP-1C significantly improved alcohol-induced liver injury by decreasing serum biochemical parameters, alleviating hepatic steatosis, and reducing lipid accumulation caused by ALD. Moreover, PCP-1C treatment reduced hepatic inflammation by inhibiting the toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway and also improved hepatocyte apoptosis by inhibiting the cytochrome P450 2E1 (CYP2E1)/reactive oxygen species (ROS)/mitogen-activated protein kinases (MAPKs) signaling pathway. Regarding intestinal protection, PCP-1C could repair the intestinal barrier and reduce lipopolysaccharide (LPS) leakage. Generally, PCP-1C exerts a positive therapeutic effect on ALD, which may play a pivotal of decreasing inflammatory factor release, inhibiting oxidative stress and apoptosis, and improving intestinal barrier injury.
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There are some limitations of traditional influenza vaccines concerning novel mutant strains. Therefore, it is particularly important to develop preventive means for antigen-unrelated types of influenza viruses. Recent studies have shown that probiotics can modulate the immune system and reduce the severity of viral infections. In this study, we investigated the potential of Lactiplantibacillus plantarum 0111 against influenza virus H9N2. Challenge experiments showed that L. plantarum 0111 pretreatments could effectively improve mice's survival rate and weight loss and reduce the inflammatory cytokines IL-6 and TNF-α in the lungs and bronchoalveolar lavage fluid (BALF) along with the degree of lung and intestinal injury. FMT experiment demonstrates that the protective effect produced by L. plantarum 0111 is associated with gut microorganisms. In addition, 16S high-throughput sequencing of the mouse intestinal microbiota showed that L. plantarum 0111 remodeled the intestinal microbiota after H9N2 infection and maintained the gut microbiota balance. In a mouse model, the oral administration of L. plantarum 0111 increased IFN-ß expression in the serum and BALF. At the same time, the transcript levels of IFN-ß and related ISGs in the intestine and lungs of mice were also increased. In addition, the activation and polarization of T cells in mesenteric lymph nodes (MLNs) and the spleen were detected by flow cytometry, and the results showed that L. plantarum 0111 modulated cytokines in T cells and increased IgA expression in B cells in the MLNs and spleen. Thus, L. plantarum 0111 may improve gut microbiota-mediated immune responses and thus, resist infection by the influenza virus, and it could be used as an effective preventive measure against the influenza virus.
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OBJECTIVE: To evaluate the myocardial protective effect of Gualou Xiebai Banxia decoction GXBD) and explore the mechanisms of inhibition of NF-kappa B activation and blockade of inflammatory responses induced by ischemia-reperfusion in rats. METHODS: Twenty-four Sprague Dawley (SD) rats were randomly divided into three groups. Rats in the treatment group received GXBD (13 g crude drug/kg) for three weeks, while rats in the model control and normal control groups received equal volumes of distilled water. On the 22nd day, rats in the ischemia-reperfusion (I/R) control and GXBD-treated groups underwent 30 min occlusion of the left anterior descending (LAD) coronary artery, followed by 120 min reperfusion. Electrocardiogram was recorded, and the activities of cardiac enzymes, cytokines, and NF-kappaB were assessed after I/R. RESULTS: Compared with the I/R control group, GXBD treatment restored the activity of the specific myocardial-injury marker creatine kinase (CK) and lactate dehydrogenase (LDH), and inhibited the inflammatory response involving the nuclear factor-kappaB (NF-KB) pathway, including down-regulation of interleukin (IL)-1beta and IL-6, and up-regulation of IL-10 gene expression. CONCLUSION: GXBD strongly reduced myocardial impairment in our I/R model, including inhibition of NF-kappaB activation and inflammatory cytokine responses.
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Medicamentos de Ervas Chinesas/administração & dosagem , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , NF-kappa B/imunologia , Animais , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Masculino , Traumatismo por Reperfusão Miocárdica/imunologia , NF-kappa B/genética , Ratos , Ratos Sprague-DawleyRESUMO
Computational ghost imaging systems reconstruct images using a single element detector, which measures the level of correlation between the scene and a set of projected patterns. The sequential nature of these measurements means that increasing the system frame-rate reduces the signal-to-noise ratio (SNR) of the captured images. Furthermore, a higher spatial resolution requires the projection of more patterns, and so both frame-rate and SNR suffer from the increase of the spatial resolution. In this work, we combat these limitations by developing a hybrid few-pixel imaging system that combines structured illumination with a quadrant photodiode detector. To further boost the SNR of our system, we employ digital micro-scanning of the projected patterns. Experimental results show that our proposed imaging system is capable of reconstructing images 4 times faster and with ~33% higher SNR than a conventional single-element computational ghost imaging system utilizing orthogonal Hadamard pattern projection. Our work demonstrates a computational imaging system in which there is a flexible trade-off between frame-rate, SNR and spatial resolution, and this trade-off can be optimized to match the requirements of different applications.
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The aim of this study is to investigate absorption-promoting mechanism of enhancers and the transport pathway of large hydrophilous molecular across rat nasal epithelium by electron spin resonance (ESR) and confocal laser scanning microscopy (CLSM) technologies. In the experiment, recombinant hirudin-2 (rHV2) was chosen as a large hydrophilic molecular model drug. After nasal administration in rats the bioavailability of rHV2 with or without various enhancers was compared. The effects of enhancers on membrane lipid fluidity and protein conformation were measured with 5-deoxyl-stearic acid (5-DSA), 16-deoxyl-stearic acid (16-DSA) and 3-maleidoproxyl (MSL) labeling ESR. The effects of enhancers on cytoskeletal F-actin of rat nasal epithelium and FITC-rHV2 transport pathway across rat nasal epithelium were performed by CLSM combined with fluorescence labeling. 0.5% Chitosan (CS), 5% hydroxyl-propyl-beta-cyclodextrin ( HP-beta-CD) and 1% ammonium glycyrrhizinate (AMGZ) were all able to significantly increase the nasal absorption of rHV2. CS could result in the paracellular pathway transport of FITC-rHV2 which seemed related to a transient effect on tight junctions. HP-beta-CD could cause paracellular and transcellular route transport of FITC-rHV2 by influencing upon membrane protein as well as lipid fluidity. AMGZ seemed to enhance the transcellular route transport of FITC-rHV2, and could exert some influence on membrane protein but not on lipid fluidity. So how it brought out this result needs further research. Present experiment may become a useful reference for promoting mechanism of enhancers and the transport pathway of large hydrophilic molecular across nasal epithelium research.
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Quitosana/farmacologia , Hirudinas/farmacocinética , Mucosa Nasal/metabolismo , Proteínas Recombinantes/farmacocinética , 2-Hidroxipropil-beta-Ciclodextrina , Absorção , Administração Intranasal , Animais , Área Sob a Curva , Disponibilidade Biológica , Transporte Biológico/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Ácido Glicirrízico/farmacologia , Hirudinas/sangue , Masculino , Microscopia Confocal , Cavidade Nasal , Coelhos , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/sangue , beta-Ciclodextrinas/farmacologiaRESUMO
Single-pixel imaging is an alternate imaging technique particularly well-suited to imaging modalities such as hyper-spectral imaging, depth mapping, 3D profiling. However, the single-pixel technique requires sequential measurements resulting in a trade-off between spatial resolution and acquisition time, limiting real-time video applications to relatively low resolutions. Compressed sensing techniques can be used to improve this trade-off. However, in this low resolution regime, conventional compressed sensing techniques have limited impact due to lack of sparsity in the datasets. Here we present an alternative compressed sensing method in which we optimize the measurement order of the Hadamard basis, such that at discretized increments we obtain complete sampling for different spatial resolutions. In addition, this method uses deterministic acquisition, rather than the randomized sampling used in conventional compressed sensing. This so-called 'Russian Dolls' ordering also benefits from minimal computational overhead for image reconstruction. We find that this compressive approach performs as well as other compressive sensing techniques with greatly simplified post processing, resulting in significantly faster image reconstruction. Therefore, the proposed method may be useful for single-pixel imaging in the low resolution, high-frame rate regime, or video-rate acquisition.
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In contrast to conventional multipixel cameras, single-pixel cameras capture images using a single detector that measures the correlations between the scene and a set of patterns. However, these systems typically exhibit low frame rates, because to fully sample a scene in this way requires at least the same number of correlation measurements as the number of pixels in the reconstructed image. To mitigate this, a range of compressive sensing techniques have been developed which use a priori knowledge to reconstruct images from an undersampled measurement set. Here, we take a different approach and adopt a strategy inspired by the foveated vision found in the animal kingdom-a framework that exploits the spatiotemporal redundancy of many dynamic scenes. In our system, a high-resolution foveal region tracks motion within the scene, yet unlike a simple zoom, every frame delivers new spatial information from across the entire field of view. This strategy rapidly records the detail of quickly changing features in the scene while simultaneously accumulating detail of more slowly evolving regions over several consecutive frames. This architecture provides video streams in which both the resolution and exposure time spatially vary and adapt dynamically in response to the evolution of the scene. The degree of local frame rate enhancement is scene-dependent, but here, we demonstrate a factor of 4, thereby helping to mitigate one of the main drawbacks of single-pixel imaging techniques. The methods described here complement existing compressive sensing approaches and may be applied to enhance computational imagers that rely on sequential correlation measurements.