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1.
Curr Microbiol ; 81(8): 243, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935166

ABSTRACT

Clostridium perfringens is one of the critical causative agents causing diarrhea in piglets, with significant economic losses to the pig industry. Under normal gut microbiota homeostasis and well-managed barns, diarrhea caused by C. perfringens could be controlled. Some reports show that probiotics, such as Bacillus subtilis, are beneficial in preventing necrotic enteritis (NE) in chickens, but few reports on piglets. Clostridium perfringens was found in the piglets' diarrhea with intestinal microbiota dysbiosis in our survey. Bacillus subtilis G2B9-Q, which was isolated from the feces of healthy pigs, was found to have anti-Clostridium activity after screening. Clostridium perfringens was used to challenge mice by intraperitoneal injection for modeling to evaluate the anti-infective activity of cell-free supernatant (CFS) of B. subtilis G2B9-Q and different concentrations of B. subtilis G2B9-Q by oral administration. The results showed that G2B9-Q can mitigate intestinal lesions caused by C. perfringens infection, reduce inflammatory reactions, and modulate intestinal microbiota. The CFS of G2B9-Q can alleviate the pathological damage of intestinal tissues caused by C. perfringens infection, reduce the concentration of TNF-α and IL-10 in the sera of mice, as well as the relative expression levels of alpha toxin (CPA), perfringolysin O (PFO) toxin, IL-10, IL-22, and TNF-α in the jejunum and colon tissues, and alleviate the changes in gut microbiota structure caused by C. perfringens infection, which showed better therapeutic effects and indicated that the metabolites of G2B9-Q are essential mediators for their beneficial effects. Therefore, the CFS of G2B9-Q could potentially replace antibiotics in treating C. perfringens infection.


Subject(s)
Bacillus subtilis , Clostridium Infections , Clostridium perfringens , Gastrointestinal Microbiome , Probiotics , Animals , Clostridium Infections/immunology , Clostridium Infections/microbiology , Bacillus subtilis/genetics , Clostridium perfringens/immunology , Mice , Probiotics/administration & dosage , Gastrointestinal Microbiome/drug effects , Intestines/microbiology , Intestines/immunology , Swine , Diarrhea/microbiology , Diarrhea/immunology , Feces/microbiology , Disease Models, Animal
2.
Chem Asian J ; 19(11): e202400163, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38606886

ABSTRACT

Pollution from harmful heavy metal ions such as Pb(II) and Cu(II) is causing serious environmental and health problems. In this study, Sodium and nitrogen co-doped porous carbon material (Na/NABc) was successfully prepared from seaweed, sodium hydroxide, and dicyandiamide. The experimental results showed that Na/NABc is an excellent adsorbent for the effective removal of Pb(II) and Cu(II) from water bodies. Specifically, 99.8% of Pb(II) and 64.6% Cu(II) (100 mg/L) were removed within 12 h using 10 mg Na/NABc(10%) at 25 °C. The adsorption of Pb(II) and Cu(II) in aqueous solution by Na/NABc(10%) was efficient and rapid in the first stage. The theoretical maximum removal capacities of Na/NABc for Pb(II) and Cu(II) were 959.6 and 299.1 mg/g, respectively. Pb(II) and Cu(II) ions were adsorbed quickly in the first 60 min, and the kinetics data were generally consistent with a pseudo-second-order model. Na/NABc(10%) had a large distribution coefficient for Pb(II) (8.38 L/mg) and Cu(II) (1.17 L/mg). The possible mechanisms were precipitation, Ion exchange, and surface complexation. The removal rate can reach about 70% after five cycles, and the release of sodium meets the standard. The results of this study demonstrate the potential applicability of Na/NABc(10%) for adsorption of heavy metals from aqueous solution.


Subject(s)
Charcoal , Copper , Lead , Nitrogen , Seaweed , Sodium , Water Pollutants, Chemical , Copper/chemistry , Lead/chemistry , Lead/isolation & purification , Seaweed/chemistry , Charcoal/chemistry , Water Pollutants, Chemical/isolation & purification , Water Pollutants, Chemical/chemistry , Adsorption , Sodium/chemistry , Nitrogen/chemistry , Water Purification/methods , Kinetics , Water/chemistry
3.
Heliyon ; 10(1): e23651, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38192752

ABSTRACT

The development of mobile networks has led to the emergence of challenges such as high delays in storage, computing and traffic management. To deal with these challenges, fifth-generation networks emphasize the use of technologies such as mobile cloud computing and mobile edge computing. Mobile Edge Cloud Computing (MECC) is an emerging distributed computing model that provides access to cloud computing services at the edge of the network and near mobile users. With offloading tasks at the edge of the network instead of transferring them to a remote cloud, MECC can realize flexibility and real-time processing. During computation offloading, the requirements of Internet of Things (IoT) applications may change at different stages, which is ignored in existing works. With this motivation, we propose a task offloading method under dynamic resource requirements during the use of IoT applications, which focuses on the problem of workload fluctuations. The proposed method uses a learning automata-based offload decision-maker to offload requests to the edge layer. An auto-scaling strategy is then developed using a long short-term memory network which can estimate the expected number of future requests. Finally, an Asynchronous Advantage Actor-Critic algorithm as a deep reinforcement learning-based approach decides to scale down or scale up. The effectiveness of the proposed method has been confirmed through extensive experiments using the iFogSim simulator. The numerical results show that the proposed method has better scalability and performance in terms of delay and energy consumption than the existing state-of-the-art methods.

4.
Bioelectromagnetics ; 45(3): 130-138, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38105659

ABSTRACT

The blood-brain barrier (BBB) is the main obstacle to hydrophilic and large molecules to enter the brain, maintaining the stability of the central nervous system (CNS). But many environmental factors may affect the permeability and structure of the BBB. Electromagnetic pulses (EMP) irradiation has been proven to enhance the permeability of the BBB, but the specific mechanism is still unclear. To explore the potential mechanism of EMP-induced BBB opening, this study investigated the permeability, fine structure and the proteins expression of the tight junction (TJ) of the BBB in the rats exposed to EMP. Using the leakage of fluorescein isothiocyanate-labeled dextran with different molecular mass under different field intensity of EMP exposure, we found that the tracer passing through the BBB is size-dependent in the rat exposed to EMP as field intensity increased. Transmission electron microscopy showed TJ of the endothelial cells in the EMP-exposed group was open, compared with the sham-irradiated group. But the levels of TJ proteins including ZO-1, claudin-5, or occludin were not changed as indicated by western blot. These data suggest that EMP induce BBB opening in a field intensity-dependent manner and probably through dysfunction of TJ proteins instead of their expression. Our findings increase the understanding of the mechanism for EMP working on the brain and are helpful for CNS protection against EMP.


Subject(s)
Blood-Brain Barrier , Tight Junctions , Rats , Animals , Blood-Brain Barrier/metabolism , Rats, Sprague-Dawley , Tight Junctions/metabolism , Endothelial Cells/metabolism , Occludin/metabolism , Electromagnetic Fields/adverse effects
5.
Int J Mol Sci ; 24(21)2023 Oct 29.
Article in English | MEDLINE | ID: mdl-37958713

ABSTRACT

Reperfusion after ischemia would cause massive myocardial injury, which leads to oxidative stress (OS). Calcium homeostasis imbalance plays an essential role in myocardial OS injury. CaV1.2 calcium channel mediates calcium influx into cardiomyocytes, and its activity is modulated by a region of calpastatin (CAST) domain L, CSL54-64. In this study, the effect of Ahf-caltide, derived from CSL54-64, on myocardial OS injury was investigated. Ahf-caltide decreased the levels of LDH, MDA and ROS and increased heart rate, coronary flow, cell survival and SOD activity during OS. In addition, Ahf-caltide permeated into H9c2 cells and increased CaV1.2, CaVß2 and CAST levels by inhibiting protein degradation. At different Ca2+ concentrations (25 nM, 10 µM, 1 mM), the binding of CSL to the IQ motif in the C terminus of the CaV1.2 channel was increased in a H2O2 concentration-dependent manner. CSL54-64 was predicted to be responsible for the binding of CSL to CaV1.2. In conclusion, Ahf-caltide exerted a cardioprotective effect on myocardial OS injury by stabilizing CaV1.2 protein expression. Our study, for the first time, proposed that restoring calcium homeostasis by targeting the CaV1.2 calcium channel and its regulating factor CAST could be a novel treatment for myocardial OS injury.


Subject(s)
Calcium , Hydrogen Peroxide , Calcium/metabolism , Hydrogen Peroxide/pharmacology , Hydrogen Peroxide/metabolism , Calcium Channels, L-Type/metabolism , Myocytes, Cardiac/metabolism , Peptides/pharmacology , Oxidative Stress
6.
Opt Lett ; 48(18): 4829-4832, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37707913

ABSTRACT

Recently, research about bound states in the continuum (BICs) has become more and more attractive. Nanostructures with rotational symmetry are usually utilized to realize polarization-independent quasi-BIC resonances. Here, we propose a new, to the best of our knowledge, scheme for a polarization-independent quasi-BIC without the help of rotational symmetry. With the rotation of the polarization direction of the incident light, a quasi-BIC resonance can be consistently observed in a dielectric cubic tetramer metasurface without rotational symmetry. Based on far-field multipolar decomposition and near-field electromagnetic distributions, it is found that different multipoles exhibit different dependences on the polarization direction, and the switch between electric and magnetic quadrupoles results in polarization-independent quasi-BIC resonance. Our findings provide an alternative scheme to design polarization-independent devices and promote wider potential applications.

7.
Aging Dis ; 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37728588

ABSTRACT

Stroke is a leading cause of death and disability in the world. Astrocytes are special glial cells within the central nervous system and play important roles in mediating neuroprotection and repair processes during stroke. Extracellular vesicles (EVs) are lipid bilayer particles released from cells that facilitate intercellular communication in stroke by delivering proteins, lipids, and RNA to target cells. Recently, accumulating evidence suggested that astrocyte-derived EVs (ADEVs) are actively involved in mediating numerous biological processes including neuroprotection and neurorepair in stroke and they are realized as an excellent therapeutic approach for treating stroke. In this review we systematically summarize the up-to-date research on ADEVs in stroke, and prospects for its potential as a novel therapeutic target for stroke. We also provide an overview of the effects and functions of ADEVs on stroke recovery, which may lead to developing clinically relevant therapies for stroke.

8.
FEMS Microbiol Lett ; 3702023 01 17.
Article in English | MEDLINE | ID: mdl-37537148

ABSTRACT

In the surveillance of outbreaks of Clostridioides difficile infection, the rapid detection and diagnosis of C. difficile remain a major challenge. Polymerase spiral reaction (PSR) is a nucleic acid amplification technique that uses mixed primers and the strand displacement activity of Bst DNA polymerase to achieve a pair of primers and a single enzyme in an isothermal environment. The primer design is simple, the reaction is efficient, and a color indicator can be used to visualize the result. In this study, we developed a rapid and visually interpretable PSR to detect C. difficile by analyzing artificially contaminated feces samples and clinical isolates from patient feces samples. We designed two pairs of primers for a PSR that specifically targeted the conserved tcdB gene of C. difficile. The amplification results were visualized with the chromogenic dye hydroxynaphthol blue. The entire process was accomplished in 50 min at 64°C, with high specificity. The limit of detection of C. difficile with PSR was 150 fg/µl genomic DNA or 2 × 10 CFU/ml in artificially contaminated feces samples. With this method, we analyzed four clinical isolates and also compared the PSR with an isolation-and-culture detection method, polymerase chain reaction, and the Sanger sequencing. The four clinical isolates were found positive for tcdB, which confirmed the high specificity of the primers. The positive rates of tcdB in toxigenic C. difficile detected with PSR, PCR, and Sanger sequencing were 100%. The proportions of toxin types in these clinical C. difficile strains were 50% tcdA+tcdB+CDT- and 50% tcdA+tcdB+CDT+. The assay described should extend our understanding of the incidence of C. difficile. This may allow the rapid diagnosis and screening of C. difficile-related disease outbreaks in the field.


Subject(s)
Bacterial Toxins , Clostridioides difficile , Clostridium Infections , Humans , Bacterial Toxins/genetics , Clostridioides difficile/genetics , Clostridioides/genetics , Polymerase Chain Reaction/methods , Clostridium Infections/diagnosis , Feces/chemistry , Nucleotidyltransferases , Bacterial Proteins/genetics , Bacterial Proteins/analysis , Enterotoxins/genetics
9.
Nanoscale ; 15(34): 14146-14154, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37591823

ABSTRACT

Chirality plays an important role in biological processes, and enantiomers often possess similar physical properties and different physiological functions. Thus, chiral detection of enantiomers has become a hot topic in recent years, and methods to enhance chiral molecular recognition are in urgent demand. In this work, a polarization detection method was used for different chiral drugs based on a specially designed metasurface composed of asymmetric double-opened rings and the surface enhancement effect of gold nanoparticles (GNPs). The experiment results show that the frequency shifts caused by the nearfield interaction of the metasurface and biomolecules have been significantly improved by GNPs, and both the limit of detection and detection precision of the metasurface can reach the 10-5 g ml-1 level. Moreover, the polarization sensing characterized by right circular polarization (RCP), the polarization elliptical angle (PEA), and the polarization rotation angle (PRA) shows that the enantiomers of three drugs can be distinguished, especially using the PEA spectrum; the maximum difference between enantiomers is over 30° with a precision of 6.6 × 10-7 g mL-1. Our THz polarization sensing and the GNP enhancement method inspire an efficient strategy for the highly sensitive detection of enantiomers.


Subject(s)
Gold , Metal Nanoparticles
10.
Clin Lab ; 69(7)2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37436374

ABSTRACT

BACKGROUND: The similarity between Crohn's disease (CD) and non-CD, especially with ulcerative colitis (UC) or intestinal tuberculosis (ITB), makes the diagnostic error rate not low. Therefore, there is an urgent need for an efficient, fast, and simple predictive model that can be applied in clinical practice. The purpose of this study is to establish the risk prediction model for CD based on five routine laboratory tests by logistic-regression algorithm, to construct the early warning model for CD and the corresponding visual nomograph, and to provide an accurate and convenient reference for the risk determination and differential diagnosis of CD, in order to assist clinicians to better manage CD and reduce patient suffering. METHODS: Using a retrospective analysis, a total of 310 cases were collected from 2020 to 2022 at The Sixth Affiliated Hospital, Sun Yat-sen University, who were diagnosed by comprehensive clinical diagnosis, including 100 patients with CD, 50 patients with ulcerative colitis (UC), 110 patients with non-inflammatory bowel disease (non-IBD) diseases (65 cases of intestinal tuberculosis, radioactive enterocolitis 39, and colonic diverticulitis 6), and 50 healthy individuals (NC) in the non-CD group. Risk prediction models were established by measuring ESR, Hb, WBC, ALb, and CH levels in hematology. The models were evaluated and visualized using logistic-regression algorithm. RESULTS: 1) ESR, WBC, and WBC/CH ratios in the CD group were higher than those in the non-CD group, while ALb, Hb, CH, WBC/ESR ratio, and Hb/WBC ratio were lower than those in the non-CD group, and the differences were statistically significant (all p < 0.05). 2) CD occurrence had a strong correlation with the WBC/CH ratio, with the correlation coefficient exceeding 0.4; CD occurrence was correlated with other indicators. 3) A risk prediction model containing age, gender, ESR, ALb, Hb, CH, WBC, WBC/CH, WBC/ESR, and Hb/WBC characteristics was constructed using a logistic-regression algorithm. The sensitivity, specificity, positive predictive value, negative predictive value, and area under the curve of the model were 83.0%, 76.2%, 59.0%, 90.5%, and 0.86, respectively. The model based on the corresponding index also had high diagnostic accuracy (AUC = 0.88) for differentiating CD from ITB. Visual nomograph based on the logistic-regression algorithm was also constructed for clinical application reference. CONCLUSIONS: In this study, a CD risk prediction model was established and visualized by five conventional hema-tological indices: ESR, Hb, WBC, ALb, and CH, in addition to a high diagnostic accuracy for the differential diagnosis of CD and ITB.


Subject(s)
Colitis, Ulcerative , Crohn Disease , Tuberculosis, Gastrointestinal , Humans , Crohn Disease/diagnosis , Colitis, Ulcerative/diagnosis , Retrospective Studies , Biomarkers/analysis , Tuberculosis, Gastrointestinal/diagnosis , Diagnosis, Differential
11.
Front Bioeng Biotechnol ; 11: 1134665, 2023.
Article in English | MEDLINE | ID: mdl-37284241

ABSTRACT

Commercial gadolinium (Gd)-based contrast agents (GBCAs) play important role in clinical diagnostic of hepatocellular carcinoma, but their diagnostic efficacy remained improved. As small molecules, the imaging contrast and window of GBCAs is limited by low liver targeting and retention. Herein, we developed a liver-targeting gadolinium (Ⅲ) chelated macromolecular MRI contrast agent based on galactose functionalized o-carboxymethyl chitosan, namely, CS-Ga-(Gd-DTPA)n, to improve hepatocyte uptake and liver retention. Compared to Gd-DTPA and non-specific macromolecular agent CS-(Gd-DTPA)n, CS-Ga-(Gd-DTPA)n showed higher hepatocyte uptake, excellent cell and blood biocompatibility in vitro. Furthermore, CS-Ga-(Gd-DTPA)n also exhibited higher relaxivity in vitro, prolonged retention and better T1-weighted signal enhancement in liver. At 10 days post-injection of CS-Ga-(Gd-DTPA)n at a dose of 0.03 mM Gd/Kg, Gd had a little accumulation in liver with no liver function damage. The good performance of CS-Ga-(Gd-DTPA)n gives great confidence in developing liver-specifc MRI contrast agents for clinical translation.

12.
Molecules ; 28(11)2023 May 23.
Article in English | MEDLINE | ID: mdl-37298734

ABSTRACT

The development of highly active and low-cost catalysts for use in oxygen reduction reaction (ORR) is crucial to many advanced and eco-friendly energy techniques. N-doped carbons are promising ORR catalysts. However, their performance is still limited. In this work, a zinc-mediated template synthesis strategy for the development of a highly active ORR catalyst with hierarchical porous structures was presented. The optimal catalyst exhibited high ORR performance in a 0.1 M KOH solution, with a half-wave potential of 0.89 V vs. RHE. Additionally, the catalyst exhibited excellent methanol tolerance and stability. After a 20,000 s continuous operation, no obvious performance decay was observed. When used as the air-electrode catalyst in a zinc-air battery (ZAB), it delivered an outstanding discharging performance, with peak power density and specific capacity as high as 196.3 mW cm-2 and 811.5 mAh gZn-1, respectively. Its high performance and stability endow it with potential in practical and commercial applications as a highly active ORR catalyst. Additionally, it is believed that the presented strategy can be applied to the rational design and fabrication of highly active and stable ORR catalysts for use in eco-friendly and future-oriented energy techniques.


Subject(s)
Carbon , Zinc , Humans , Porosity , Drug Tolerance , Hypoxia , Reactive Oxygen Species , Oxygen
13.
RSC Adv ; 13(22): 15327-15333, 2023 May 15.
Article in English | MEDLINE | ID: mdl-37223644

ABSTRACT

Algae biochar (ABC), coconut shell biochar (CSBC), and coconut coat biochar (CCBC) were prepared by wet pyrolysis in a phosphoric acid solvent under normal pressure. Materials were characterized for their micromorphology, specific surface area, and surface functional groups by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) nitrogen adsorption-desorption spectrum technique and Fourier transform infrared diffraction (FT-IR). The evaluation of the liquid-phase adsorption performance using methylene blue (MB) as a pigment model, and the effects of temperature, pH, adsorbent dosage, and pollutant concentration of the MB adsorption onto modified biochars were fully investigated. The adsorption mechanism was proposed based on the adsorption kinetics curve and adsorption isotherm. The synthetic biochar showed great adsorption properties toward cationic dyes rather than anionic dyes. Specifically, the adsorption abilities for algal biochar, coconut shell biochar, and coconut coat biochar were determined to be 97.5%, 95.4% and 21.2%, respectively. The isothermal adsorption of MB by the three kinds of biochar conformed to the Langmuir equation, and the adsorption process fitted to the quasi-second-order kinetic equation, which suggested that ABC and CSBC effectively adsorbed MB dye molecules through hydrogen bonding, π-π stacking, and electrostatic interactions.

14.
Sensors (Basel) ; 23(7)2023 Apr 04.
Article in English | MEDLINE | ID: mdl-37050792

ABSTRACT

The differential microphone array, or differential beamformer, has attracted much attention for its frequency-invariant beampattern, high directivity factor and compact size. In this work, the design of differential beamformers with small inter-element spacing planar microphone arrays is concerned. In order to exactly control the main lobe beamwidth and sidelobe level and obtain minimum main lobe beamwidth with a given sidelobe level, we design the desired beampattern by applying the Chebyshev polynomials at first, via exploiting the structure of the frequency-independent beampattern of a theoretical Nth-order differential beamformer. Next, the so-called null constrained and least square beamformers, which can obtain approximately frequency-invariant beampattern at relatively low frequencies and can be steered to any direction without beampattern distortion, are proposed based on planar microphone arrays to approximate the designed desired beampatterns. Then, for dealing with the white noise amplification at low-frequency bands and beampattern divergence problems at high-frequency bands of the null constrained and least square beamformers, the so-called minimum norm and combined solutions are deduced, which can compromise among the white noise gain, directivity factor and beampattern distortion flexibly. Preliminary simulation results illustrate the properties and advantages of the proposed differential beamformers.

15.
Biomed Opt Express ; 14(3): 1096-1106, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36950227

ABSTRACT

The efficient sensing of amino acids, especially the distinction of their chiral enantiomers, is important for biological, chemical, and pharmaceutical research. In this work, a THz phase shift sensing method was performed for amino acid detection based on a polarization-dependent electromagnetically induced transparency (EIT) metasurface. More importantly, a method for binding the specific amino acids to the functional proteins modified on the metasurface was developed based on the isoelectric point theory so that the specific recognition for Arginine (Arg) was achieved among the four different amino acids. The results show that via high-Q phase shift, the detection precision for L-Arg is 2.5 × 10-5 g /ml, much higher than traditional sensing parameters. Due to the specific electrostatic adsorption by the functionalized metasurface to L-Arg, its detection sensitivity and precision are 22 times higher than the other amino acids. Furthermore, by comparing nonfunctionalized and functionalized metasurfaces, the D- and L-chiral enantiomers of Arg were distinguished due to their different binding abilities to the functionalized metasurface. Therefore, this EIT metasurface sensor and its specific binding method improve both detection precision and specificity in THz sensing for amino acids, and it will promote the development of THz highly sensitive detection of chiral enantiomers.

16.
Opt Express ; 31(2): 1269-1281, 2023 Jan 16.
Article in English | MEDLINE | ID: mdl-36785166

ABSTRACT

Active manipulation of terahertz (THz) beam deflection and intensity is highly desired for possible applications in wireless communication, radar, and remote sensing. Here, by integrating the phase-gradient metasurfaces and tunable liquid crystal materials, we demonstrate an active THz beam deflection device based on polarization mode conversion. The resonant modes in the photonic cavity formed by the double-layer metasurface and the tunable anisotropic liquid crystal material in the cavity not only improve the polarization conversion efficiency of the device, but also actively regulate the resonance matching conditions. As a consequence, a beam deflection of 47.5° with 50% diffraction intensity at 0.69 THz is achieved in the x-to-y polarization conversion mode, and this beam can be actively modulated with an ultrahigh modulation depth of 99.6% by rotating the anisotropic optical axis of liquid crystals. Moreover, the proposed device can also work as the deflection of 32.5° in the y-to-x polarization conversion mode at 0.94 THz with a maximum diffraction intensity of 38% and an intensity modulation depth of 97.8%. This work provides a new approach based on liquid crystal photonic devices for wavefront manipulation and active modulation for THz waves.

17.
Curr Med Imaging ; 19(12): 1427-1435, 2023.
Article in English | MEDLINE | ID: mdl-36757033

ABSTRACT

BACKGROUND: PET imaging is one of the most widely used neurological disease screening and diagnosis techniques. AIMS: Since PET involves the radiation and tolerance of different people, the improvement that has always been focused on is to cut down radiation, in the meantime, ensuring that the generated images with low-dose tracer and generated images with standard-dose tracer have the same details of images. METHODS: We propose a lightweight low-dose PET super-resolution network (SRPET-Net) based on a convolutional neural network. In this research, We propose a method for accurately recovering highresolution (HR) PET images from low-resolution (LR) PET images. The network learns the details and structure of the image between low-dose PET images and standard-dose PET images and, afterward, reconstructs the PET image by the trained network model. RESULTS: The experiments indicate that the SRPET-Net can achieve a superior peak signal-to-noise ratio (PSNR) and structural similarity index measurement (SSIM) values. Moreover, our method has less memory consumption and lower computational cost. CONCLUSION: In our follow-up work, the technology can be applied to medical imaging in many different directions.


Subject(s)
Deep Learning , Humans , Neural Networks, Computer , Image Processing, Computer-Assisted/methods , Positron-Emission Tomography , Signal-To-Noise Ratio
18.
Comput Math Methods Med ; 2022: 1968829, 2022.
Article in English | MEDLINE | ID: mdl-36277017

ABSTRACT

Background: Lymph node metastasis is an important route of lung cancer metastasis and can significantly affect the survival of lung cancer. Methods: All the analysis was conducted out in the R software. Expression profile and clinical information of lung adenocarcinoma (LUAD) patients were downloaded from The Cancer Genome Atlas database. Results: In our study, we firstly identified the characteristic genes of lymph node metastasis in LUAD through two machine learning algorithms, least absolute shrinkage and selection operator (LASSO) logistic regression, and SVM-RFE algorithms. Ten characteristic genes were finally identified, including CRHR2, ITIH1, PRSS48, MAS1L, CYP4Z1, LMO1, TCP10L2, KRT78, IGFBP1, and PITX3. Next, we performed univariate Cox regression, LASSO regression, and multivariate Cox regression sequentially to construct a prognosis model based on MAS1L, TCP10L2, and CRHR2, which had a good prognosis prediction efficiency in both training and validation cohorts. Univariate and multivariate analysis indicated that our model is a risk factor independent of other clinical features. Pathway enrichment analysis showed that in the high-risk patients, the pathway of MYC target, unfolded protein response, interferon alpha response, DNA repair, reactive oxygen species pathway, and glycolysis were significantly enriched. Among three model genes, MAS1L aroused our interest and therefore was selected for further analysis. KM survival curves showed that the patients with higher MAS1L might have better disease-free survival and progression-free survival. Further, pathway enrichment, genomic instability, immune infiltration, and drug sensitivity analysis were performed to in-deep explore the role of MAS1L in LUAD. Conclusions: Results showed that the signature based on MAS1L, TCP10L2, and CRHR2 is a useful tool to predict prognosis and lung cancer lymph node metastasis.


Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Humans , Lymphatic Metastasis/genetics , Reactive Oxygen Species/metabolism , Kaplan-Meier Estimate , Gene Expression Regulation, Neoplastic , Adenocarcinoma of Lung/pathology , Lung Neoplasms/metabolism , Machine Learning , Interferon-alpha/genetics , Interferon-alpha/metabolism , Cytochrome P450 Family 4/genetics , Cytochrome P450 Family 4/metabolism
19.
Appl Opt ; 61(21): 6391-6397, 2022 Jul 20.
Article in English | MEDLINE | ID: mdl-36256255

ABSTRACT

Terahertz (THz) waves have attracted much attention in the field of biosensing due to advantages including non-destructiveness, being label-free, and high-sensitivity detection. Here we have experimentally demonstrated a THz polarization sensing method based on reflective metasurface sensors for detecting concentrations of protein solutions and their crystallization process. The protein with varying concentrations has been detected by five different polarization parameters, which show different spectral responses and sensing sensitivities. The sensing accuracy can reach the order of ng/mm2. Furthermore, the crystallization process of the protein sample from the dissolved state to the crystalline has been dynamically measured by polarization sensing, of which the highest sensitivity can reach 0.67 °/%. Therefore, this new sensing platform can have broad development prospects in the trace matter detection of the biological sample.


Subject(s)
Crystallization , Biosensing Techniques
20.
Molecules ; 27(19)2022 Oct 05.
Article in English | MEDLINE | ID: mdl-36235140

ABSTRACT

To build a portable and sensitive method for monitoring the concentration of the flavonoid rutin, a new electrochemical sensing procedure was established. By using nitrogen-doped carbonized polymer dots (N-CPDs) anchoring few-layer black phosphorene (N-CPDs@FLBP) 0D-2D heterostructure and gold nanoparticles (AuNPs) as the modifiers, a carbon ionic liquid electrode and a screen-printed electrode (SPE) were used as the substrate electrodes to construct a conventional electrochemical sensor and a portable wireless intelligent electrochemical sensor, respectively. The electrochemical behavior of rutin on the fabricated electrochemical sensors was explored in detail, with the analytical performances investigated. Due to the electroactive groups of rutin, and the specific π-π stacking and cation-π interaction between the nanocomposite with rutin, the electrochemical responses of rutin were greatly enhanced on the AuNPs/N-CPDs@FLBP-modified electrodes. Under the optimal conditions, ultra-sensitive detection of rutin could be realized on AuNPs/N-CPDs@FLBP/SPE with the detection range of 1.0 nmol L-1 to 220.0 µmol L-1 and the detection limit of 0.33 nmol L-1 (S/N = 3). Finally, two kinds of sensors were applied to test the real samples with satisfactory results.


Subject(s)
Ionic Liquids , Metal Nanoparticles , Nanocomposites , Carbon/chemistry , Electrochemical Techniques/methods , Electrodes , Gold/chemistry , Limit of Detection , Metal Nanoparticles/chemistry , Nanocomposites/chemistry , Nitrogen , Polymers , Rutin/chemistry
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