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1.
J Vis Exp ; (207)2024 May 24.
Article in English | MEDLINE | ID: mdl-38856215

ABSTRACT

This study showcases a comprehensive treatment protocol for high-risk hepatocellular carcinoma (HCC) patients, focusing on the combined use of Y-90 transarterial radioembolization (TARE) and Programmed Cell Death-1 (PD-1) inhibitors as neoadjuvant therapy. Highlighted through a case report, it offers a step-by-step reference for similar therapeutic interventions. A retrospective analysis was conducted on a patient who underwent hepatectomy following Y-90 TARE and PD-1 inhibitor treatment. Key demographic and clinical details were recorded at admission to guide therapy selection. Y-90 TARE suitability and dosage calculation were based on Technetium-99m (Tc-99m) macroaggregated albumin (MAA) perfusion mapping tests. Lesion coverage by Y-90 microspheres was confirmed through single photon emission computed tomography/computed tomography (SPECT/CT) fusion imaging, and adverse reactions and follow-up outcomes were meticulously documented. The patient, with a 7.2 cm HCC in the right hepatic lobe (T1bN0M0, BCLC A, CNLC Ib) and an initial alpha-fetoprotein (AFP) level of 66,840 ng/mL, opted for Y-90 TARE due to high recurrence risk and initial surgery refusal. The therapy's parameters, including the lung shunting fraction (LSF) and non-tumor ratio (TNR), were within therapeutic limits. A total of 1.36 GBq Y-90 was administered. At 1 month post-therapy, the tumor shrank to 6 cm with partial necrosis, and AFP levels dropped to 21,155 ng/mL, remaining stable for 3 months. After 3 months, PD-1 inhibitor treatment led to further tumor reduction to 4 cm and AFP decrease to 1.84 ng/mL. The patient then underwent hepatectomy; histopathology confirmed complete tumor necrosis. At 12 months post-surgery, no tumor recurrence or metastasis was observed in follow-up sessions. This protocol demonstrates the effective combination of Y-90 TARE and PD-1 inhibitor as a bridging strategy to surgery for HCC patients at high recurrence risk, providing a practical guide for implementing this approach.


Subject(s)
Carcinoma, Hepatocellular , Embolization, Therapeutic , Liver Neoplasms , Neoadjuvant Therapy , Yttrium Radioisotopes , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/therapy , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/therapy , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Neoadjuvant Therapy/methods , Embolization, Therapeutic/methods , Yttrium Radioisotopes/therapeutic use , Male , Retrospective Studies , Immune Checkpoint Inhibitors/therapeutic use , Middle Aged , Aged , Radiopharmaceuticals/therapeutic use
2.
Materials (Basel) ; 16(4)2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36837174

ABSTRACT

Arc floating in surface flashover can be controlled by reducing the interfacial charge-transfer resistance of ceramics. However, thus far, only a few studies have been conducted on methods of treating ceramic surfaces directly to reduce the interfacial charge-transfer resistance. Herein, we explore the flash sintering behavior of a ceramic surface (3 mol% yttria-stabilized zirconia (3YSZ)) onto which loose metal (iron) powder was spread prior to flash sintering at room temperature (25 °C). The iron powder acts as a conductive phase that accelerates the start of flash sintering while also doping the ceramic phase during the sintering process. Notably, the iron powder substantially reduces the transition time from the arc stage to the flash stage from 13.50 to 8.22 s. The surface temperature (~1600 °C) of the ceramic substrate is sufficiently high to melt the iron powder. The molten metal then reacts with the ceramic surface, causing iron ions to substitute Zr4+ ions and promoting rapid densification. The YSZ grains in the metal-infiltrated area grow exceptionally fast. The results demonstrate that spreading metal powder onto a ceramic surface prior to flash sintering can enable the metal to enter the ceramic pores, which will be of significance in developing and enhancing ceramic-metal powder processing techniques.

3.
Materials (Basel) ; 15(11)2022 May 27.
Article in English | MEDLINE | ID: mdl-35683132

ABSTRACT

(Mg, Co, Ni, Cu, Zn)1-xLixO is a type of high-entropy oxide that has high ionic conductivity at room temperature and is used as a solid electrolyte. (Mg, Co, Ni, Cu, Zn)1-xLixO was successfully synthesized from precursor powder by applying reactive flash sintering for less than 4 min at room temperature (25 °C). AC and DC electric fields were independently applied to sinter ceramic samples; consequently, AC and DC electric field application resulted in relative densities that exceeded 90% and 80%, respectively. X-ray diffraction spectra of samples revealed the existence of a clear halite structure with an insignificant impurity phase, proving that (Mg, Co, Ni, Cu, Zn)1-xLixO crystals were successfully produced.

4.
Front Bioeng Biotechnol ; 10: 826093, 2022.
Article in English | MEDLINE | ID: mdl-35372314

ABSTRACT

Background: Drug-induced liver injury is one of the main reasons of withdrawals of drugs in postmarketing stages. However, an experimental model(s) which can accurately recapitulates liver functions and reflects the level of drug hepatotoxicity is lack. In this study, we assessed drug hepatotoxicity using a novel three-dimensional hepatic plate-like hydrogel fiber (3D-P) co-culture system. Methods: During the 28-days culture period, the liver-specific functions, hepatocyte polarity, sensitivity of drug-induced toxicity of 3D-P co-culture system were evaluated with 2D co-culture, collagen sandwich co-culture, 3D hybrid hydrogel fiber co-culture and human primary hepatocytes as controls. High-content imaging and analysis (HCA) methods were used to explore the hepatotoxicity mechanism of five statins. Results: The 3D-P co-culture system showed enhancing liver-specific functions, cytochrome P450 enzymes (CYPs) metabolic activity and bile excretion, which were considered to result from improved hepatocyte polarity. Three of the statins may cause acute or chronic hepatotoxicity by via different mechanisms, such as cholestatic liver injury. Conclusion: Our 3D-P co-culture system is characterized by its biomimetic hepatic plate-like structure, long-term stable liver specificity, and prominent bile secretion function, making it applicable for acute/chronic drug hepatotoxicity assessments.

5.
Materials (Basel) ; 15(3)2022 Jan 23.
Article in English | MEDLINE | ID: mdl-35160805

ABSTRACT

Ceramic flash sintering with a strong electric field at room temperature is the most attractive method. This paper presents the flash sintering of ZnO ceramics at room temperature by the application of a 3-kV/cm electric field after a dropwise addition of ethanol. This method is simple and easy to control. The density of the specimen exceeded 96% after 30 s of sintering. No significant difference was observed in the initiation voltage of flash sintering with and without the dropwise addition of ethanol. Ethanol burns upon dropwise addition, causing a discharge to first occur far from the location of the dropwise addition, followed by glowing and heating up, which causes the temperature of the entire specimen to rise.

6.
Biomed Res Int ; 2020: 6354183, 2020.
Article in English | MEDLINE | ID: mdl-32190673

ABSTRACT

In vitro 3D hepatocyte culture constitutes a core aspect of liver tissue engineering. However, conventional 3D cultures are unable to maintain hepatocyte polarity, functional phenotype, or viability. Here, we employed microfluidic chip technology combined with natural alginate hydrogels to construct 3D liver tissues mimicking hepatic plates. We comprehensively evaluated cultured hepatocyte viability, function, and polarity. Transcriptome sequencing was used to analyze changes in hepatocyte polarity pathways. The data indicate that, as culture duration increases, the viability, function, polarity, mRNA expression, and ultrastructure of the hepatic plate mimetic 3D hepatocytes are enhanced. Furthermore, hepatic plate mimetic 3D cultures can promote changes in the bile secretion pathway via effector mechanisms associated with nuclear receptors, bile uptake, and efflux transporters. This study provides a scientific basis and strong evidence for the physiological structures of bionic livers prepared using 3D cultures. The systems and cultured liver tissues described here may serve as a better in vitro 3D culture platform and basic unit for varied applications, including drug development, hepatocyte polarity research, bioartificial liver bioreactor design, and tissue and organ construction for liver tissue engineering or cholestatic liver injury.


Subject(s)
Biomimetics/methods , Cell Culture Techniques/methods , Cell Polarity/physiology , Hepatocytes/cytology , Hepatocytes/metabolism , Liver/cytology , Liver/metabolism , Alginates , Cell Culture Techniques/instrumentation , Endothelial Cells , Gene Expression , Humans , Hydrogels , Lab-On-A-Chip Devices , Liver, Artificial , RNA, Messenger/metabolism , Tissue Engineering/methods , Transcriptome
7.
Molecules ; 25(4)2020 Feb 13.
Article in English | MEDLINE | ID: mdl-32070039

ABSTRACT

Surface pollution deposition in a high voltage surface can reduce the surface flashover voltage, which is considered to be a serious accident in the transmission of electric power for the high conductivity of pollution in wet weather, such as rain or fog. Accordingly, a rapid and accurate online pollution detection method is of great importance for monitoring the safe status of transmission lines. Usually, to detect the equivalent salt deposit density (ESDD) and non-soluble deposit density (NSDD), the pollution should be collected when power cut off and bring back to lab, time-consuming, low accuracy and unable to meet the online detection. Laser-induced breakdown spectroscopy (LIBS) shows the highest potential for achieving online pollution detection, but its application in high voltage electrical engineering has only just begun to be examined. In this study, a LIBS method for quantitatively detecting the compositions of pollutions on the insulators was investigated, and the spectral characteristics of a natural pollution sample were examined. The energy spectra and LIBS analysis results were compared. LIBS was shown to detect pollution elements that were not detected by conventional energy spectroscopy and had an improved capacity to determine pollution composition. Furthermore, the effects of parameters, such as laser energy intensity and delay time, were investigated for artificial pollutions. Increasing the laser energy intensity and selecting a suitable delay time could enhance the precision and relative spectral intensities of the elements. Additionally, reducing the particle size and increasing the density achieved the same results.


Subject(s)
Environmental Pollution/analysis , Lasers , Spectrum Analysis/methods
8.
Polymers (Basel) ; 11(8)2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31374843

ABSTRACT

Metal cabinets such as switch cabinets and ring network cabinets have the advantages of small footprints and good protection for equipment and offer neat and orderly protection. They are widely used in power systems. In a hot and humid environment, condensation can easily cause equipment to age and even cause insulation failure. Therefore, research on reliable anticondensation methods is of great significance for the safe operation of power equipment. In this study, phase change capsules with phase transition temperatures of 22 and 32 °C were used as fillers and liquid silicone rubber was used as a matrix to prepare liquid silicone rubber composites filled with phase change capsules for a temperature-control coating. Studies have shown that liquid silicone rubber coatings containing phase change capsules can significantly enhance the anticondensation performance of metal cabinets. By using a temperature-control coating on the surface where the cabinet experiences condensation, the temperature difference between the surface and the dew point is reduced, thereby slowing down the condensation rate and even preventing condensation.

9.
Sensors (Basel) ; 19(5)2019 Mar 03.
Article in English | MEDLINE | ID: mdl-30832442

ABSTRACT

Silicone rubber material is widely used in high-voltage external insulation systems due to its excellent hydrophobicity and hydrophobicity transfer performance. However, silicone rubber is a polymeric material with a poor ability to resist electrical tracking and erosion; therefore, some fillers must be added to the material for performance enhancement. The inclined plane test is a standard method used for evaluating the tracking and erosion resistance by subjecting the materials to a combination of voltage stress and contaminate droplets to produce failure. This test is time-consuming and difficult to apply in field inspection. In this paper, a new and faster way to evaluate the tracking and erosion resistance performance is proposed using laser-induced breakdown spectroscopy (LIBS). The influence of filler content on the tracking and erosion resistance performance was studied, and the filler content was characterized by thermogravimetric analysis and the LIBS technique. In this paper, the tracking and erosion resistance of silicone rubber samples was correctly classified using principal component analysis (PCA) and neural network algorithms based on LIBS spectra. The conclusions of this work are of great significance to the performance characterization of silicone rubber composite materials.

10.
Molecules ; 23(12)2018 Nov 30.
Article in English | MEDLINE | ID: mdl-30513654

ABSTRACT

Recently, composite materials with nonlinear dielectric or resistive properties performed well in electric field homogenization and space charge suppression in a high voltage transmission and distribution system. For the purpose of obtaining insulation materials with desirable dielectric and electrical resistance properties, we investigated several fillers with nonlinear electrical properties doped in silicon rubber composites, and their dependency on the temperature and field. The samples of silicone rubber composites with different components were prepared using barium strontium titanate (BST) and zinc oxide (ZnO) as the filler, and high temperature vulcanized silicone rubber (SiR) as the matrix. The investigations revealed that the BST-doped samples showed different dielectric properties compared to ZnO-doped composites, with an increase in the electric field, which was nonlinear. The resistivity of both doped samples was similar. Results demonstrated that it was possible to achieve higher values of permittivity, and lower values of tanδ and resistivity, with respect to unfilled silicone rubber composites over a wide electrical field and temperature range. Discussion of the results attributes these important functional behaviours to the spontaneous polarization of nonlinear nanoparticles and the interaction between the SiR chains and the nonlinear nanoparticles at the interfacial area.


Subject(s)
Electricity , Nanoparticles/chemistry , Nonlinear Dynamics , Oxides/chemistry , Silicone Elastomers/chemistry , Strontium/chemistry , Titanium/chemistry , Zinc Oxide/chemistry , Computer Simulation , Electric Conductivity , Nanoparticles/ultrastructure , X-Ray Diffraction
11.
World J Gastroenterol ; 24(30): 3398-3413, 2018 Aug 14.
Article in English | MEDLINE | ID: mdl-30122879

ABSTRACT

AIM: To develop a novel hepatocyte serum-free medium based on sericin, and to explore the effect of sericin on the hepatocyte transcriptome. METHODS: A controlled trial comparing novel serum-free medium and other media: C3A cells were cultured in our novel serum-free medium, HepatoZYME, complete medium (DMEM/F12 with 100 mL/L FBS), and DMEM/F12, and then cell attachment, proliferation, and function as well as the biocompatibility of the media were assessed. A comparative study of serum-free media with or without 2 mg/mL sericin: the effect of sericin on C3A growth was assessed by cell viability and proliferation, the effect of sericin on C3A cell cycle distribution was determined by flow cytometry, and the effect of sericin on the C3A transcriptome was assessed by gene-chip array and RT-qPCR. RESULTS: More C3A cells attached to the plate containing our serum-free medium than to those containing HepatoZYME and DMEM/F12 at 24 h post-seeding. Both the viability and proliferation rate of C3A cells in sericin-based serum-free medium were superior to those of cells in HepatoZYME and DMEM/F12 (P < 0.001). The content of albumin and urea in our serum-free medium was significantly higher than that in HepatoZYME and DMEM/F12 throughout the whole culture period (P < 0.001) and was similar to that in complete medium at day 3, 4, and 5. In part 2, cell viability and proliferation were greater in the presence of 2 mg/mL sericin (P < 0.001), as was the proportion of cells in S phase (16.21% ± 0.98% vs 12.61% ± 0.90%, P < 0.01). Gene-chip array analysis indicated that the expression of CCR6, EGFR, and FOS were up-regulated by 2 mg/mL sericin, and RT-qPCR revealed that the expression of CCR6, EGFR, FOS, AKT1, JNK1, NFkB1, MMP-9, MEK2, ERK1/2 and MYC was up-regulated by 2 mg/mL sericin (P < 0.05). CONCLUSION: We developed a novel hepatocyte serum-free medium. Sericin probably enhances cell attachment through the CCR6-Akt-JNK-NF-κB pathway and promotes cell proliferation through CCR6-mediated activation of the ERK1/2-MAPK pathway.


Subject(s)
Cell Culture Techniques/methods , Hepatocytes/drug effects , Sericins/pharmacology , Transcriptome/drug effects , Cell Adhesion/drug effects , Cell Division/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Culture Media, Serum-Free/chemistry , Culture Media, Serum-Free/pharmacology , Gene Expression Profiling/methods , Hepatocytes/metabolism , Humans , Oligonucleotide Array Sequence Analysis/methods
12.
Sensors (Basel) ; 18(8)2018 Aug 10.
Article in English | MEDLINE | ID: mdl-30103396

ABSTRACT

The fast detection of classical contaminants and their distribution on high-voltage transmission line insulators is essential for ensuring the safe operation of the power grid. The analysis of existing insulator contamination has traditionally relied on taking samples during a power cut, taking the samples back to the lab and then testing them with elemental analysis equipment, especially for sugars, bird droppings, and heavy metal particulates, which cannot be analysed by the equivalent salt deposit density (ESDD) or non-soluble deposit density (NSDD) methods. In this study, a novel method called laser-induced breakdown spectroscopy (LIBS) offering the advantages of no sample preparation, being nearly nondestructive and having a fast speed was applied for the analysis of metal contamination. Several LIBS parameters (laser energy and delay time) were optimized to obtain better resolution of the spectral data. The limit of detection (LOD) of the observed elements was obtained using a calibration curve. Compared to calibration curves, multivariate analysis methods including principal component analysis (PCA), k-means and partial least squares regression (PLSR) showed their superiority in analyzing metal contamination in insulators. Then, the elemental distribution of natural pollution was predicted using LIBS to fully capture information about the bulk elements (Na, Ni, Cu, Mn, Ca, etc.) of entire areas with PLSR. The results showed that LIBS could be a promising method for accurate direct online quantification of metal contamination in insulators.

13.
J Mater Sci Mater Med ; 29(5): 49, 2018 Apr 19.
Article in English | MEDLINE | ID: mdl-29675647

ABSTRACT

Liver is one of the most important organ in the body. But there are many limitations about liver transplantation for liver failure. It is quite important to develop the xenogeneic biological liver for providing an alternation to transplantation or liver regeneration. In this paper, we proposed a method to construct a novel kind of agarose 3D-culture concave microwell array for spheroids formation of hepatic cells. Using the 3D printing method, the microwell array was fabricated with an overall size of 6.4 mm × 6.4 mm, containing 121 microwells with 400 µm width/400 µm thickness. By exploiting the Polydimethylsiloxane (PDMS) membranes as a bridge, we finally fabricated the agarose one. We co-cultured three types of liver cells with bionics design in the microwell arrays. Using the methods described above, the resulting co-formed hepatocyte spheroids maintained the high viability and stable liver-specific functions. This engineered agarose concave microwell array could be a potentially useful tool for forming the elements for biological liver support. After developing the complete system, we also would consider to scale up the application of this system. It will be not only applied to the therapy of human organ damage, but also to the development of disease models and drug screening models.


Subject(s)
Cell Culture Techniques/instrumentation , Hepatocytes/cytology , Microtechnology/methods , Sepharose/chemistry , Spheroids, Cellular/cytology , Tissue Array Analysis/instrumentation , Cells, Cultured , Coculture Techniques , Dimethylpolysiloxanes/chemistry , Hepatocytes/physiology , Humans , Liver/cytology , Liver/physiology , Membranes, Artificial , Spheroids, Cellular/physiology
14.
J Biomater Appl ; 32(1): 93-103, 2017 07.
Article in English | MEDLINE | ID: mdl-28504559

ABSTRACT

Background/aims The critical part of a bio-artificial liver device is establishment of a bioreactor filled with liver cells. However, it is still unclear how to maintain benign cell function while achieving the sufficient cell quantity. In the current study, we aim to establish a novel carrier for the culture of HepG2 cells, a liver cell line, by modifying polypropylene nonwoven fabrics with native type I collagen. Methods "Piranha" solution, KH-550 and glutaraldehyde subsequently were used to bridge native type I collagen and polypropylene nonwoven fabrics. The type I collagen-coupled polypropylene nonwoven fabric was characterized by XPS, SEM, ATR-FTIR and water contact angle measurement. Furthermore, the biocompatibility between HepG2 cells and fiber film is evaluated by the ability of cell proliferation, albumin secretion, as well as urea synthesis. Results The coating of collagen onto polypropylene fabrics was more efficient using the chemical covalent binding method than direct immersion, which was validated by the presence of collagen-related elements and chemical bond. The adding of collagen in polypropylene fabrics promoted hydrophilicity and HepG2 cell adherence. Additionally, enhanced cell proliferation, increased albumin secretion and urea synthesis were observed in HepG2 cells growing on collagen-coated polypropylene fabrics. Conclusions The collagen coated polypropylene nonwoven fabrics, acting as a feasible substrate for HepG2 cell culture, may be used as a promising liver cell carrier for artificial liver reactor.


Subject(s)
Biocompatible Materials/chemistry , Collagen Type I/chemistry , Hepatocytes/cytology , Polypropylenes/chemistry , Animals , Cattle , Cell Culture Techniques , Cell Proliferation , Glutaral/chemistry , Hep G2 Cells , Hepatocytes/metabolism , Humans , Immobilized Proteins/chemistry , Liver, Artificial , Surface Properties , Textiles
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(8): 2122-5, 2009 Aug.
Article in Chinese | MEDLINE | ID: mdl-19839322

ABSTRACT

Inactivation effect of pulsed electric field (PEF) on polyphenol oxidase (PPO) and lipoxygenase (LOX) was investigated using a laboratory PEF system with a coaxial treatment chamber. Circular dichroism (CD) and fluorescence analysis were used to study the conformation change of the protein. The experimental results show that PPO and LOX can be effectively inactivated by the PEF treatment. Inactivation effect of PPO and LOX increases with the increase in the applied electric strength and the treatment time. Activity of PPO and LOX can be reduced by 60.3% and 21.7% at 20 kV x cm(-1) after being treated for 320 micros respectively. The decrease of the negative peaks (208 and 215 nm in PPO spectra, 208 nm and 218 nm in LOX spectra) in CD spectra of PPO and LOX shows that PEF treatment caused a loss of alpha-helix and increase in beta-sheet content, indicating that conformation changes occur in the secondary structure of PPO and LOX enzyme. This effect was strengthened as the applied electric field increased: alpha-helical content of PPO and LOX was 56% and 29% after being treated at 8 kV x cm(-1), however, when the electric field was increased up to 20 kV x cm(-1), alpha-helical content of PPO and LOX decreased to 21% and 16% respectively. The decrease rate of alpha-helix and increase rate of beta-sheet in PPO are higher than LOX, indicating that the second conformation of PPO is less resistant to PEF treatment than LOX. The fluorescence intensity of LOX increases after PEF treatment. At the same time, increasing the applied pulsed electric field increases the fluorescence intensity emitted. Fluorescence measurements confirm that tertiary conformation changes occur in the local structure of LOX. However the possible mechanism of the conformation change induced by the PEF treatment is beyond the scope of the present investigation.


Subject(s)
Catechol Oxidase/chemistry , Lipoxygenase/chemistry , Circular Dichroism , Electricity , Fluorescence , Protein Structure, Secondary
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