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1.
Sensors (Basel) ; 24(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38610359

RESUMO

Targets faced by inverse synthetic aperture radar (ISAR) are often non-cooperative, with target maneuvering being the main manifestation of this non-cooperation. Maneuvers cause ISAR imaging results to be severely defocused, which can create huge difficulties in target identification. In addition, as the ISAR bandwidth continues to increase, the impact of migration through resolution cells (MTRC) on imaging results becomes more significant. Target non-cooperation may also result in sparse aperture, leading to the failure of traditional ISAR imaging algorithms. Therefore, this paper proposes an algorithm to realize MTRC correction and sparse aperture ISAR imaging for maneuvering targets simultaneously named whale optimization algorithm-fast iterative shrinkage thresholding algorithm (WOA-FISTA). In this algorithm, FISTA is used to perform MTRC correction and sparse aperture ISAR imaging efficiently and WOA is adopted to estimate the rotational parameter to eliminate the effects of maneuvering on imaging results. Experimental results based on simulation and measured datasets prove that the proposed algorithm implements sparse aperture ISAR imaging and MTRC correction for maneuvering targets simultaneously. The proposed algorithm achieves better results than traditional algorithms under different signal-to-noise ratio conditions.

2.
Electrophoresis ; 44(13-14): 1057-1067, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37015868

RESUMO

Liver cancer is generally considered the leading cause of cancer deaths worldwide, and hepatocellular carcinoma (HCC) contributes to more than 90% of liver cancers. The altered lipid metabolism for rapid cancer cell growth and tumor formation has been frequently proven. In this study, an ambient ionization mass spectrometry technique, rapid evaporative ionization mass spectrometry (REIMS) using a monopolar electric knife, called iKnife, was systematically optimized and employed for ex vivo analysis of 12 human HCC tumor tissue specimens together with the paired paracancerous tissue (PT) and noncancerous liver tissue (NCT) specimens. Nine free fatty acids and 34 phospholipids were tentatively identified according to their extract masses and/or tandem mass spectra. With the help of statistical methods, 7 free fatty acids and 10 phospholipids were distributed differently in 3 types of liver tissue specimens (95% confidence interval). The box plots showed these characterized lipid metabolites varied in PT, HCC, and NCT. Compared with PT and NCT, the upregulations of four common fatty acids FA 18:0, FA 20:4, FA 16:0, and FA 18:1, together with phospholipids PC 36:1, PE 38:3, PE (18:0/20:4), PA (O-36:1), PC (32:1), PC 32:0, PE 34:0, and PC (16:0/18:1), were found in HCC specimens. The sensitivity and specificity of the established statistic model for real-time HCC tumor diagnosis were 100% and 90.5%, respectively. This study demonstrated that the described REIMS technique is a potential method for rapid lipidomic analysis and characterization of HCC tumor tissue.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Lipidômica , Neoplasias Hepáticas/diagnóstico , Ácidos Graxos não Esterificados , Fosfolipídeos/química , Espectrometria de Massas em Tandem
3.
Artigo em Inglês | MEDLINE | ID: mdl-37581974

RESUMO

In real networks, communication constraints often prevent the full exchange of information between nodes, which is inevitable. This brief investigates the problem of time delay and randomly missing data in Boolean networks (BNs). A Bernoulli random variable is assigned to each node to characterize the probability of data packet dropout. Time delay and missing data are modeled by independent random variables. A novel data-sending rule that incorporates both communication constraints is proposed. An augmented system, comprising current states, delayed information, and successfully transmitted data, is established for theoretical analysis. Using the semitensor product (STP), the necessary and sufficient condition for asymptotic stability of delayed BNs with random data dropouts is derived. The convergence rate is also obtained.

4.
Probiotics Antimicrob Proteins ; 14(2): 372-383, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35079949

RESUMO

Bacillus sp. DU-106, a potential probiotic, has been proved to activate innate immunity, reduce hypercholesterolemia, and regulate the gut microbiota of mice. In the present study, we investigated the therapeutic effect of strain DU-106 in antibiotic-associated diarrhea (AAD) via analyzing the changes in gut microbial composition in mice. The results indicated that supplementation of strain DU-106 alleviated gastrointestinal symptoms, improved gut barrier integrity and immunoglobulin-A level of mice with AAD. A 16S rRNA sequencing showed that antibiotics decreased bacterial diversity and the abundances of Alistipes, Roseburia, Hungatella, Eubacterium-xylanophilum, Lachnospiraceae-UCG-001, Intestinimonas, and Lachnospiraceae-NK4A136, but increased the abundance of Klebsiella, Bacteroidota, and Verrucomicrobiota. However, strain DU-106 treatment reversed these alternations in mice with AAD. In conclusion, strain DU-106 could alleviate AAD in association with the regulation of intestinal microbiota and could be used as an alternative treatment for AAD.


Assuntos
Bacillus , Microbioma Gastrointestinal , Probióticos , Animais , Antibacterianos/farmacologia , Bacillus/genética , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Camundongos , Probióticos/uso terapêutico , RNA Ribossômico 16S/genética
5.
Front Chem ; 10: 964744, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910733

RESUMO

Salvia miltiorrhiza Bunge (SMB) has unambiguous biological functions in cardiovascular diseases, thus has been processed into different medicine forms. However, universal analytical method for fast quantification of bioactive compounds in SMB and SMB derived products is still missing. In this study, a polarity switching strategy was developed and optimized, which enabled the detection of the target compound in both positive and negative ion modes in a single run. The MS2 features of each compound were characterized to select the most prominent transitions for quantitative and qualitative analysis. Afterwards, the performance of this method was validated in terms of linearity (≥0.9916), limit of detection (LOD, 0.003-0.135 ngml-1), limit of quantification (LOQ, 0.010-0.450 ngml-1), precision (48.23 ± 2.58 ngml-1 to 53.72 ± 3.11 ngml-1), recovery (RSD 2.04%-5.79%), and stability (RSD ≤7.52%). Finally, the bioactive compounds in SMB and SMB derived products were determined, among which salvianate A, salvianolic acid A, and rosmarinic acid were the main components in all samples. In conclusion, the polarity switching UPLC-MS/MS method is efficient in accurate determining the bioactive compounds, which greatly shorten the time for analysis when compared with conventional methods. It has great potential quality control of SMB and SMB derived products.

6.
J Pharm Biomed Anal ; 189: 113467, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32683191

RESUMO

Jia-Wei-Qi-Fu-Yin (JWQFY) is a newly developed anti-Alzheimer's disease (AD) prescription modified from a classical traditional Chinese medicine formula, Qi-Fu-Yin (QFY). However, a systematic understanding of its chemical constituents and molecular mechanisms is still elusive. To address this problem, comprehensive chemical profiling followed by network pharmacology-based analysis of JWQFY was performed. Firstly, a total of 136 compounds were characterized by high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF MS), 17 of them were specifically identified in JWQFY comparing with QFY. Seventy compounds were further quantified via a validated HPLC coupled with triple quadrupole tandem mass spectrometry (QQQ MS) method. Then the protein targets of the seventy compounds were gathered from public databases for network construction. As a result, fifty-seven compounds were filtered, which interacted with 655 targets. Thirty-four of them were mapped into the KEGG pathway of AD, indicating JWQFY might exert anti-AD effects by anti-inflammation, neuronal apoptosis intervening, Aß production inhibition and phosphorylating tau protein moderating. Furthermore, in the compound-target-AD network, a list of hub compounds and hub targets was identified based on their topological features, including the degree, node betweenness and closeness. Four of the hub compounds were specifically originated from JWQFY, supporting the modification rationality of this formula. This study provided a scientific basis for understanding the bioactive compounds and the multi-target mechanism of JWQFY.


Assuntos
Doença de Alzheimer , Medicamentos de Ervas Chinesas , Doença de Alzheimer/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas em Tandem
7.
Hepatobiliary Pancreat Dis Int ; 1(3): 434-7, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14607722

RESUMO

OBJECTIVES: To evaluate endoscopic duodenal sphincterotomy and improve its success rate. METHODS: Needle-shaped knife was used for endoscopic sphincterotomy (EST) in 476 patients with biliary or pancreatic diseases from March 1995 to October 2000. RESULTS: Direct incision was made in 243 patients, papillary fenestration in 89, and opposite incision in 144. The papilla located beside and in the diverticulum in 56 and 12 patients, respectively. EST emergency was made in 147 patients. ERCP after EST because of the difficulty in intubation was made successfully in 62 patients. Mild complications occurred in 14 patients (2.94%), all of whom were cured after symptomatic treatment. CONCLUSIONS: EST with needle-shaped knife has such advantages as safety in operation and convenience in incision. It is suitable for the papilla with different shape, with a higher success rate.


Assuntos
Doenças dos Ductos Biliares/cirurgia , Pancreatopatias/cirurgia , Esfinterotomia Endoscópica/instrumentação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colangite/etiologia , Desenho de Equipamento , Feminino , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/etiologia , Estudos Retrospectivos , Esfinterotomia Endoscópica/efeitos adversos
8.
Zhonghua Gan Zang Bing Za Zhi ; 10(1): 21-4, 2002 Feb.
Artigo em Zh | MEDLINE | ID: mdl-11856494

RESUMO

OBJECTIVE: To evaluate the effect of glycogen on calcium concentration of rabbit donor liver during ischemia-reperfusion period. METHODS: Donor group (n=21) was divided into 3 subgroups randomly: Group A (n=7): fasting for 24 hours before harvesting; Group B (n=7): normal laboratory chew; Group C (n=7): normal laboratory chew plus glucose supplement intravenously. Based on the self-created animal model for ischemia-reperfusion, the levels of glycogen content, ATP level, viability of Ca(2+)ATPase and plasmic free Ca(2+) concentration ([Ca(2+)]i) of liver tissue were measured. RESULTS: Before cold preservation, there was a significant difference of glycogen content among the three groups at all time points except at the end of rewarming period. ATP level and Ca(2+)ATPase viability were significantly higher in group C than in other two groups. But the plasmic free Ca(2+) concentration was lower in groups with higher glycogen content. CONCLUSIONS: Donor liver with high glycogen content can provide relatively sufficient ATP, maintain better Ca(2+)ATPase viability and prevent plasmic free Ca(2+) concentration overloading. This maybe an important mechanism for glycogen to ameliorate ischemia-reperfusion injury to the donor livers.


Assuntos
Trifosfato de Adenosina/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Glicogênio/metabolismo , Hepatopatias/metabolismo , Transplante de Fígado/fisiologia , Traumatismo por Reperfusão/metabolismo , Animais , Citosol/química , Feminino , Hepatopatias/enzimologia , Masculino , Modelos Animais , Coelhos , Traumatismo por Reperfusão/enzimologia
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