Reconstruction of central arterial pressure waveform based on CBi-SAN network from radial pressure waveform.

The central arterial pressure (CAP) is an important physiological indicator of the human cardiovascular system which represents one of the greatest threats to human health. Accurate non-invasive detection and reconstruction of CAP waveforms are crucial for the reliable treatment of cardiovascular system diseases. However, the traditional methods are reconstructed with relatively low accuracy, and some deep learning neural network models also have difficulty in extracting features, as a result, these methods have potential for further advancement. In this study, we proposed a novel model (CBi-SAN) to implement an end-to-end relationship from radial artery pressure (RAP) waveform to CAP waveform, which consisted of the convolutional neural network (CNN), the bidirectional long-short-time memory network (BiLSTM), and the self-attention mechanism to improve the performance of CAP reconstruction. The data on invasive measurements of CAP and RAP waveform were used in 62 patients before and after medication to develop and validate the performance of CBi-SAN model for reconstructing CAP waveform. We compared it with traditional methods and deep learning models in mean absolute error (MAE), root mean square error (RMSE), and Spearman correlation coefficient (SCC). Study results indicated the CBi-SAN model performed great performance on CAP waveform reconstruction (MAE: 2.23 ± 0.11 mmHg, RMSE: 2.21 ± 0.07 mmHg), concurrently, the best reconstruction effect was obtained in the central artery systolic pressure (CASP) and the central artery diastolic pressure(CADP) (RMSECASP: 2.94 ± 0.48 mmHg, RMSECADP: 1.96 ± 0.06 mmHg). These results implied the performance of the CAP reconstruction based on CBi-SAN model was superior to the existing methods, hopped to be effectively applied to clinical practice in the future.

Deep learning-based lung image registration: A review.

Lung image registration can effectively describe the relative motion of lung tissues, thereby helping to solve series problems in clinical applications. Since the lungs are soft and fairly passive organs, they are influenced by respiration and heartbeat, resulting in discontinuity of lung motion and large deformation of anatomic features. This poses great challenges for accurate registration of lung image and its applications. The recent application of deep learning (DL) methods in the field of medical image registration has brought promising results. However, a versatile registration framework has not yet emerged due to diverse challenges of registration for different regions of interest (ROI). DL-based image registration methods used for other ROI cannot achieve satisfactory results in lungs. In addition, there are few review articles available on DL-based lung image registration. In this review, the development of conventional methods for lung image registration is briefly described and a more comprehensive survey of DL-based methods for lung image registration is illustrated. The DL-based methods are classified according to different supervision types, including fully-supervised, weakly-supervised and unsupervised. The contributions of researchers in addressing various challenges are described, as well as the limitations of these approaches. This review also presents a comprehensive statistical analysis of the cited papers in terms of evaluation metrics and loss functions. In addition, publicly available datasets for lung image registration are also summarized. Finally, the remaining challenges and potential trends in DL-based lung image registration are discussed.

Development of a sensitive chicken IgY-based enzyme-linked immunosorbent assay for detection of mebendazole in pork and mutton.

Chicken egg yolk IgY has proven to be qualified for analysis of targets in immunoassays. In order to explore the feasibility of chicken IgY-based ELISA for detection of mebendazole (MEB), the chicken IgY against MEB was generated in the laying hens. An enzyme-linked immunosorbent assay (ELISA) based on chicken IgY was developed for detection of MEB with a half-maximum signal inhibition concentration (IC50) of 3.65 ng mL-1 and a limit of detection of 0.25 ng mL-1. The assay showed a lower cross reactivity (less than 1%) with other structures analogues (except amino-MEB with the values of 70.7%). The average recoveries of MEB spiked in pork and mutton muscle samples ranged from 93.6% to 106.3% with relative standard deviation less than 8.78% and 10.85% for intra-assay and inter-assay, respectively, and agreed well with those of high-performance liquid chromatography. Our results indicate that generated IgY could be used as a robust reagent for routine screening analysis of small molecular compounds residues in food samples.

Multivalent nanobody-biotin amplified enzyme-linked immunosorbent assay for the environmental detection of 3-phenoxybenzoic acid.

The 3-phenoxybenzoic acid (3-PBA) metabolized from pyrethroids is more toxic and has a longer half-life to degradation in a natural environment compared to its parent compounds. Few reports have focused on the environmental detection of 3-PBA. In this study, anti-3-PBA nanobodies in trivalent form (Nb3) were biotinylated. A sensitive enzyme-linked immunosorbent assay (ELISA) based on the combination of Nb3-biotin and streptavidin-horseradish peroxidase (SA-HRP) was developed for the environmental detection of 3-PBA. After optimization, the ELISA showed a half-maximum signal inhibition concentration (IC50) of 0.39 ng mL-1 in phosphate-buffered saline (pH 7, 20% MeOH) and a limit of detection (LOD) of 0.02 ng mL-1, which was more sensitive than the parent Nb-based ELISAs with IC50 and LOD values of 1.4 ng mL-1 and 0.1 ng mL-1, respectively. The Nb3-biotin amplified assay showed negligible cross-reactivity with its structural analogues (<0.1%). The average recoveries of 3-PBA from spiked canal water and soil samples ranged from 86.54-109.25% at 0.5-50 ng mL-1 (or ng g-1 (dw)). The 3-PBA residues in canal water and soil samples determined using this assay were in the ranges

An EPDM/MVQ polymer blend based magnetorheological elastomer with good thermostability and mechanical performance.

Magnetorheological elastomers (MREs) with outstanding magnetic-control properties are highly desirable for applications such as vibration attenuation, smart sensing, and soft robots. However, the low strength and thermolability of these materials still restrict their application in attenuating the vibration of large-scale devices. In this paper, we prepared an MRE based on ethylene-propylene-diene monomer (EPDM)/methylvinyl silicone rubber (MVQ) polymer blends. The resulting MRE showed good thermostability and mechanical properties. Good interfacial interaction and particle dispersion were achieved by modifying the surface of carbonyl iron powder (CIP) with silica coating by the sol-gel method. The compatibility between the EPDM and MVQ was promoted using silane coupling agents. Moreover, the resulting MRE had high mechanical strength and elongation at break. The dynamic viscoelastic properties of the MRE were tested using a rheometer. The influences of frequency, strain, matrices, temperature, and magnetic fields were discussed comprehensively, and relevant physical mechanisms were proposed. Finally, thermal aging tests were performed to evaluate the heat resistance of the MRE. Analytical results showed that the resulting MRE could be significantly applied to reduce the vibration of large devices because of its excellent mechanical properties and thermostability.

Collagen scaffolds tethered with bFGF promote corpus spongiosum regeneration in a beagle model.

Regeneration of the corpus spongiosum helps prevent complications following urethral reconstruction, but currently there is a lack of effective therapeutic methods in clinic. In previous studies, we fabricated a fusion protein collagen-binding domain (CBD)-basic fibroblast growth factor (bFGF) that specifically binds to and releases from collagen biomaterials. We demonstrated that CBD-bFGF could promote angiogenesis and tissue regeneration in vivo. In this study, we established a beagle model with extensive urethral defects, and reconstructed the defects with collagen biomaterials that were unmodified or modified with CBD-bFGF. The results demonstrate that CBD-bFGF promotes corpus spongiosum regeneration resulting in improved outcomes following urethral reconstruction. Modifying collagen biomaterials with CBD-bFGF may represent an effective strategy for urethral substitution in urethral reconstruction.

Uranium biosorption from aqueous solution by the submerged aquatic plant Hydrilla verticillata.

The biosorption characteristics of U(VI) from aqueous solution onto a nonliving aquatic macrophyte, Hydrilla verticillata (dry powder), were investigated under various experimental conditions by using batch methods. Results showed that the adsorption reached equilibrium within 60 min and the experimental data were well fitted by the pseudo-first-order kinetic model. U(VI) adsorption was strongly pH dependent, and the optimum pH for U(VI) removal was 5.5. Isotherm adsorption data displayed good correlation with the Langmuir model, with a maximum monolayer adsorption capacity of 171.52 mg/g. Thermodynamic studies suggested that U(VI) adsorption onto H. verticillata was an exothermic and spontaneous process in nature. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy indicated that the amino and hydroxyl groups on the algal surface played an important role in U(VI) adsorption. The mechanisms responsible for U(VI) adsorption could involve electrostatic attraction and ion exchange. In conclusion, H. verticillata biomass showed good potential as an adsorption material for the removal of uranium contaminants in aqueous solution.

Effects of ligand density and pore size on the adsorption of bovine IgG with DEAE ion-exchange resins.

Immunoglobulin G is an important plasma protein with many applications in therapeutics and diagnostics, which can be purified effectively by ion exchange chromatography. The ligand densities and pore properties of ion-exchange resins have significant effects on the separation behaviors of protein, however, the understandings are quite limited. In this work, with bovine immunoglobulin as the model IgG, the adsorption isotherms and adsorption kinetics were investigated systematically with series of diethylaminoethyl ion-exchange resins with different ligand densities and pore sizes. The Langmuir equation and pore diffusion model were used to fit the experimental data. The influences of ligand density and pore size on the saturated adsorption capacity, the dissociation constant and the effective diffusivity were discussed. The adsorption capacities increased with the increase of ligand density and the decrease of pore size, and an integrative parameter was proposed to describe the combined effects of ligand density and pore size. It was also found that the effective pore diffusion coefficient of the adsorption kinetics was influenced by pore sizes of resins, but was relatively independent on the ligand densities of resins. For a given protein, the ligand density and pore size should be optimized for improving the protein adsorption.

Protein adsorption on DEAE ion-exchange resins with different ligand densities and pore sizes.

Ion exchange chromatography (IEC) is a common and powerful technique for the purification of proteins. The ligand density and pore properties of ion-exchange resins have significant effects on the separation behaviors of protein, however, the understandings are quite limited. In the present work, the adsorption isotherms of bovine serum albumin (BSA) and human serum albumin (HSA) were investigated systematically with series of diethylaminoethyl (DEAE) ion-exchange resins, which have different ligand densities and pore sizes. The Langmuir equation was used to fit the experimental data and the influences of ligand density and pore size on the saturated adsorption capacity and the dissociation constant were discussed. The zeta potentials and hydrodynamic diameters of proteins at different pHs were also measured, and the surface charge characteristics of proteins and the adsorption mechanism were discussed. The results demonstrated that the ligand density, pore size, and protein properties affect the protein adsorption capacities in an integrative way. An integrative parameter was introduced to describe the complicated effects of ligand density and pore size on the protein adsorption. For a given protein, the ligand density and pore size should be optimized for improving the protein adsorption.

[Effects of lycopene on blood cells and fibrinolytic activity in hyperlipidemic rats].

OBJECTIVE: To explore the effects of lycopene on blood cells and fibrinolytic activity in hyperlipidemic rats. METHODS: Forty adult male SD rats were divided randomly into five groups: normal control group, high fat model group, fluvastatin sodium group, lycopene low-dose group and lycopene high-dose group based on the level of serum TC. Normal control group was fed with normal animal diet, other groups were fed with high fat diet. Fluvastatin sodium and lycopene were given by intragastric administration in the last two weeks of experiment. The level of serum lipid, SOD, MDA, blood cell parameters, platelet (granule membrane protein (GMP-140), tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) were measured. The pathological changes of aorta were observed and atherosclerosis index was calculated. RESULTS: Hyperlipidemia was induced in rats after feeding high fat diet for one week. In comparison with high fat diet model group, serum TC, TG, LDL-C and MDA were decreased but HDL-C and SOD were increased in lycopene groups. White blood cell count, mean volume of red blood cells and platelets, GMP-140 and PAI-1 were decreased, but red blood cell count and tPA were increased; atherosclerosis index were decreased, foam cells were decreased in intima, pathological changes in aorta were reduced in lycopene groups. The effects were obvious in lycopene 44 mg/kg bw group. CONCLUSION: The effect of lycopene on protecting blood cell, promoting fibrinolytic activity and reducing aortic lesions in hyperlipidemic rats might be the result of reducing blood lipids and improving antioxidation.