An Iterative Deconvolution-Time Reversal Method with Noise Reduction, a High Resolution and Sidelobe Suppression for Active Sonar in Shallow Water Environments.

Matched filtering is widely used in active sonar because of its simplicity and ease of implementation. However, the resolution performance generally depends on the transmitted waveform. Moreover, its detection performance is limited by the high-level sidelobes and seriously degraded in a shallow water environment due to time spread induced by multipath propagation. This paper proposed a method named iterative deconvolution-time reversal (ID-TR), on which the energy of the cross-ambiguity function is modeled, as a convolution of the energy of the auto-ambiguity function of the transmitted signal with the generalized target reflectivity density. Similarly, the generalized target reflectivity density is a convolution of the spread function of channel with the reflectivity density of target as well. The ambiguity caused by the transmitted signal and the spread function of channel are removed by Richardson-Lucy iterative deconvolution and the time reversal processing, respectively. Moreover, this is a special case of the Richardson-Lucy algorithm that the blur function is one-dimensional and time-invariant. Therefore, the iteration deconvolution is actually implemented by the iterative temporal time reversal processing. Due to the iterative time reversal method can focus more and more energy on the strongest target with the iterative number increasing and then the peak-signal power increases, the simulated result shows that the noise reduction can achieve 250 dB in the "ideal" free field environment and 100 dB in a strong multipaths waveguide environment if a 1-ms linear frequency modulation with a 4-kHz frequency bandwidth is transmitted and the number of iteration is 10. Moreover, the range resolution is approximately a delta function. The results of the experiment in a tank show that the noise level is suppressed by more than 70 dB and the reverberation level is suppressed by 3 dB in the case of a single target and the iteration number being 8.

[Effect of Huangdi Anxiao Capsules on zebrafish vascular lesions induced by high glucose and high fat].

Zebrafish of different strains with 5 dpf (5 days post-fertilization) were selected and fed with 0.2% high-fat diet for 8 h and 3% glucose solution for 16 halternatively during the day and night for 4 consecutive days. The zebrafish model was established and randomly divided into model group, Huangdi Anxiao Capsules (260 mg·L⁻¹) group and pioglitazone (32 mg·L⁻¹) group. The drug treatment groups were given the water-soluble drugs, with a volume of 25 mL, and incubated in a 28 °C incubator for 4 days. To detect the exposure to the corresponding drugs, the normal control group was set up. Thirty zebrafish were included in each group. The effect of Huangdi Anxiao Capsules on vascular wall thickness, fluorescence intensity of islet beta cells, fluorescence intensity of macrophages, and blood flow velocity of zebrafish were detected. The expressions of vascular endothelial growth factor (vegfaa) and angiotensin converting enzyme (ACE) were detected by RT-PCR. The results showed that compared with the model group, Huangdi Anxiao Capsules can significantly reduce the thickness of the blood vessel wall, increase the fluorescence intensity of islet ß cells and macrophages, increase the blood flow velocity in vivo, and decrease the ACE and vegfaa expressions in zebrafish. It is suggested that Huangdi Anxiao Capsules may alleviate zebrafish vascular lesions by regulating the expressions of ACE and vegfaa.

Uncovering the Mechanism of Astragalus membranaceus in the Treatment of Diabetic Nephropathy Based on Network Pharmacology.

BACKGROUND: Diabetic nephropathy (DN), characterized by hyperglycemia, hypertension, proteinuria, and edema, is a unique microvascular complication of diabetes. Traditional Chinese medicine (TCM) Astragalus membranaceus (AM) has been widely used for DN in China while the pharmacological mechanisms are still unclear. This work is aimed at undertaking a network pharmacology analysis to reveal the mechanism of the effects of AM in DN. Materials and Methods. In this study, chemical constituents of AM were obtained via Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), and the potential targets of AM were identified using the Therapeutic Target Database (TTD). DisGeNET and GeneCards databases were used to collect DN-related target genes. DN-AM common target protein interaction network was established by using the STRING database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were carried out to further explore the DN mechanism and therapeutic effect of AM. The network diagrams of the active component-action target and protein-protein interaction (PPI) networks were constructed using Cytoscape software. RESULTS: A total of 16 active ingredients contained and 78 putative identified target genes were screened from AM, of which 42 overlapped with the targets of DN and were considered potential therapeutic targets. The analysis of the network results showed that the AM activity of component quercetin, formononetin, calycosin, 7-O-methylisomucronulatol, and quercetin have a good binding activity with top ten screened targets, such as VEGFA, TNF, IL-6, MAPK, CCL3, NOS3, PTGS2, IL-1ß, JUN, and EGFR. GO and KEGG analyses revealed that these targets were associated with inflammatory response, angiogenesis, oxidative stress reaction, rheumatoid arthritis, and other biological process. CONCLUSIONS: This study demonstrated the multicomponent, multitarget, and multichannel characteristics of AM, which provided a novel approach for further research of the mechanism of AM in the treatment of DN.

To Explore the Pathogenesis of Vascular Lesion of Type 2 Diabetes Mellitus Based on the PI3K/Akt Signaling Pathway.

BACKGROUND: Type 2 diabetes mellitus (T2DM) has become a chronic disease, serious harm to human health. Complications of the blood pipe are the main cause of disability and death in diabetic patients, including vascular lesions that directly affects the prognosis of patients with diabetes and survival. This study was to determine the influence of high glucose and related mechanism of vascular lesion of type 2 diabetes mellitus pathogenesis. METHODS: In vivo aorta abdominalis of GK rats was observed with blood pressure, heart rate, hematoxylin and eosin (H&E), Masson, and Verhoeff staining. In vitro cells were cultured with 30 mM glucose for 24 h. RT-QPCR was used to detect the mRNA expression of endothelial markers PTEN, PI3K, Akt, and VEGF. Immunofluorescence staining was used to detect the expression of PTEN, PI3K, Akt, and VEGF. PI3K and Akt phosphorylation levels were detected by Western blot analysis. RESULTS: Heart rate, systolic blood pressure, diastolic blood pressure, and mean blood pressure in the GK control group were higher compared with the Wistar control group and no difference compared with the GK experimental model group. Fluorescence intensity of VEGF, Akt, and PI3K in the high-sugar stimulus group was stronger than the control group; PTEN in the high-sugar stimulus group was weakening than the control group. VEGF, Akt, and PI3K mRNA in the high-sugar stimulus group were higher than the control group; protein expressions of VEGF, Akt, and PI3K in the high-sugar stimulus group were higher than the control group. PTEN mRNA in the high-sugar stimulus group was lower than the control group. Protein expression of PTEN in the high-sugar stimulus group was lower than the control group. CONCLUSIONS: Angiogenesis is an important pathogenesis of T2DM vascular disease, and PTEN plays a negative regulatory role in the development of new blood vessels and can inhibit the PI3K/Akt signaling pathway.

Potential role of lncRNAs in contributing to pathogenesis of chronic glomerulonephritis based on microarray data.

BACKGROUND: Chronic glomerulonephritis (CGN) is the most common form of primary glomerular disease with unclear molecular mechanisms, which related to immune-mediated inflammatory diseases. Our study intended to identify potential long non-coding RNAs (lncRNAs) and genes, and to determine the potential molecular mechanisms of CGN pathogenesis. METHODS: The microarray of GSE64265 and GSE46295 were downloaded from the Gene Expression Omnibus database, GSE64265 including 3 rats control kidney tissues and 5 rats model kidney tissues, GSE46295 including 3 rats control kidney tissues and 3 rats model kidney tissues, which was on the basis of GPL1355 platform. Identification of differentially expressed lncRNAs and mRNAs were performed between the 2 groups. Gene ontology (GO) and pathway enrichment analyses were performed to analyze the biological functions and pathways for the differentially expressed mRNAs. LncRNA-mRNA weighted co-expression network was constructed using the WGCNA package to analyses for the genes in the modules. The protein-protein interaction (PPI) network was visualized. RESULTS: A total of 40 significantly up-regulated and 24 down-regulated lncRNAs, 653 up-regulated and 128 down-regulated mRNAs were identified. Additionally, Cdk1, with the highest connectivity degree in PPI network, was noteworthy enriched in cell cycle. Seven lncRNAs: NONRATT026650, LOC102547664, NONRATT77021989, NONRATT012453, LOC102551856, LOC102553536 and NONRATT7047175 were observed in the modules of lncRNA-mRNA weighted co-expression network. CONCLUSIONS: LncRNAs NONRATT026650, LOC102547664, NONRATT77021989, NONRATT012453, LOC102551856, LOC102553536 and NONRATT7047175 were differentially expressed and might play important roles in the development of CGN. Key genes, such as Cd44, Rftn1, Runx1, may be crucial biomarkers for CGN.