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1.
Sci Technol Adv Mater ; 24(1): 2260301, 2023.
Article in English | MEDLINE | ID: mdl-37854120

ABSTRACT

This study introduces an approach to overcome the limitations of conventional pressure sensors by developing a thin and lightweight composite film specifically tailored for flexible capacitive pressure sensors, with a particular emphasis on the medium and high pressure range. To accomplish this, we have engineered a composite film by combining polyvinylidene fluoride (PVDF) and graphite nanoplatelets (GNP) derived from expanded graphite (Ex-G). A uniform sized GNPs with an average lateral size of 2.55av and an average thickness of 33.74 av with narrow size distribution was obtained with a gas-induced expansion of expandable graphite (EXP-G) combined with tip sonication in solvent. By this precisely controlled GNP within the composite film, a remarkable improvement in sensor sensitivity has been achieved, surpassing 4.18 MPa-1 within the pressure range of 0.1 to 1.6 MPa. This enhancement can be attributed to the generation of electric charge from the movement of GNP in the polymer matrix. Additionally, stability testing has demonstrated the reliable operation of the composite film over 1000 cycles. Notably, the composite film exhibits exceptional continuous pressure sensing capabilities with a rapid response time of approximately 100 milliseconds. Experimental validation using a 3 × 3 sensor array has confirmed the accurate detection of specific contact points, thus highlighting the potential of the composite film in selective pressure sensing. These findings signify an advancement in the field of flexible capacitive pressure sensors that offer enhanced sensitivity, consistent operation, rapid response time, and the unique ability to selectively sense pressure.

2.
Materials (Basel) ; 15(12)2022 Jun 14.
Article in English | MEDLINE | ID: mdl-35744268

ABSTRACT

Thermoelectric generators are solid-state energy-converting devices that are promising alternative energy sources. However, during the fabrication of these devices, many waste scraps that are not eco-friendly and with high material cost are produced. In this work, a simple powder processing technology is applied to prepare n-type Bi2Te3 pellets by cold pressing (high pressure at room temperature) and annealing the treatment with a canning package to recycle waste scraps. High-pressure cold pressing causes the plastic deformation of densely packed pellets. Then, the thermoelectric properties of pellets are improved through high-temperature annealing (500 ∘C) without phase separation. This enhancement occurs because tellurium cannot escape from the canning package. In addition, high-temperature annealing induces rapid grain growth and rearrangement, resulting in a porous structure. Electrical conductivity is increased by abnormal grain growth, whereas thermal conductivity is decreased by the porous structure with phonon scattering. Owing to the low thermal conductivity and satisfactory electrical conductivity, the highest ZT value (i.e., 1.0) is obtained by the samples annealed at 500 ∘C. Hence, the proposed method is suitable for a cost-effective and environmentally friendly way.

3.
Nanomaterials (Basel) ; 12(12)2022 Jun 10.
Article in English | MEDLINE | ID: mdl-35745351

ABSTRACT

Dopamine is a neurotransmitter that helps cells to transmit pulsed chemicals. Therefore, dopamine detection is crucial from the viewpoint of human health. Dopamine determination is typically achieved via chromatography, fluorescence, electrochemiluminescence, colorimetry, and enzyme-linked methods. However, most of these methods employ specific biological enzymes or involve complex detection processes. Therefore, non-enzymatic electrochemical sensors are attracting attention owing to their high sensitivity, speed, and simplicity. In this study, a simple one-step fabrication of a Bi2Te3-nanosheet/reduced-graphene-oxide (BT/rGO) nanocomposite was achieved using a hydrothermal method to modify electrodes for electrochemical dopamine detection. The combination of the BT nanosheets with the rGO surface was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and Fourier-transform infrared spectroscopy. Electrochemical impedance spectroscopy, cyclic voltammetry, and differential pulse voltammetry were performed to analyze the electrochemical-dopamine-detection characteristics of the BT/rGO nanocomposite. The BT/rGO-modified electrode exhibited higher catalytic activity for electrocatalytic oxidation of 100 µM dopamine (94.91 µA, 0.24 V) than that of the BT-modified (4.55 µA, 0.26 V), rGO-modified (13.24 µA, 0.23 V), and bare glassy carbon electrode (2.86 µA, 0.35 V); this was attributed to the synergistic effect of the electron transfer promoted by the highly conductive rGO and the large specific surface area/high charge-carrier mobility of the two-dimensional BT nanosheets. The BT/rGO-modified electrode showed a detection limit of 0.06 µM for dopamine in a linear range of 10-1000 µM. Additionally, it exhibited satisfactory reproducibility, stability, selectivity, and acceptable recovery in real samples.

4.
Transl Androl Urol ; 10(2): 954-962, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33718095

ABSTRACT

Proteolysis-TArgeting Chimeras (PROTACs) technology, as a strategy to chemically knock down transcription factors at the protein levels, can hijack the ubiquitin-proteasome degradation system to initiate the intracellular ubiquitin-proteasome hydrolysis process to degrade proteins. In the past, the development of drugs that target transcription factors has been greatly restricted, and even historically transcription factors have been regarded as "undruggable targets". PROTAC technology breaks through this limitation with its unique targeting design. With several generations of technical innovation, PROTACs have become more mature and continue to make breakthroughs in the field of targeted therapy including prostate cancer (PCa), with a new strategy for the development of anti-tumor targeted drugs. PROTACs have all the advantages of existing small molecule inhibitors, are easy to administer orally, have good cell permeability, and have wider targeting profiles compared to conventional inhibitors. The disadvantage of PROTACs is the noncancer specificity, off-target and sustained-release control, due to its catalytic role. Some androgen receptor (AR) and CDK4/6 degraders have advanced the field of PCa treatment, which is being further modified given the effects of these degraders in preclinical and clinical studies. This review summarizes in detail the technological progress and challenges that have been faced with PROTACs, the progress of research on PCa, and the prospective future of PROTACs development.

5.
J Cancer ; 12(24): 7349-7357, 2021.
Article in English | MEDLINE | ID: mdl-35003355

ABSTRACT

The role of lysyl oxidase (LOX) in prostate cancer remains controversial. Studies have shown that LOX may inhibit the progression of prostate cancer (PCa), whereas other studies demonstrate that LOX may act as a tumor activator in PCa. Here, we report that low LOX expression contributes to CRPC progression through upregulation of IGFBP3. We showed that LOX expression decreased in the more advanced and aggressive castration-resistant prostate cancer (CRPC), compared to castration-sensitive prostate cancer (CSPC). We demonstrated that LOX was negatively correlated with IGFBP3 and may directly bind to the promoter of IGFBP3 and thus decrease the expression of IGFBP3. Inhibition of IGFBP3 by siRNA suppressed the growth and migration of CRPC cells, suggesting a critical role for IGFBP3 in CRPC. The preclinical study in a mouse model suggested that introducing back LOX inhibited the progression of CRPC. In summary, we identified a new function of LOX in PCa and discovered that LOX downregulation contributed to progression via IGFBP3, and that the restoration of LOX may be a promising therapeutic strategy for PCa.

6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(4): 497-503, 2020 Aug 30.
Article in Chinese | MEDLINE | ID: mdl-32895102

ABSTRACT

Objective To develop an ideal surgical procedure for neobladder reconstruction in experimental porcine models. Methods Six experimental female pigs weighting 28-33 kg underwent transplantation of autologous peritoneum for bladder reconstruction under general anesthesia.The flaps were used to reconstruct the orthotopic neobladder by suturing with the edges of the triangle and neck of the remnant bladder.The ureteral catheters were removed on the 5 th postoperative day and the balloon catheter was removed on the 7 th postoperative day.Voiding behaviour was monitored.The animals were euthanized at week 12 for routine pathology,immunohistochemistry,and electron microscopy. Results All the pigs survived after the surgery,and no postoperative complication such as peritonitis,intestinal obstruction,or urinary fistula was observed.All the peritoneum-ileum composite free valves survived after transplantation.Voiding behaviour was normal after catheter removal,and the urine was clear.At autopsy,reconstructed bladders were healthy.Pathological examination showed the neobladder had been covered by continuous urothelium while the peritoneum disappeared and showed no ileal mucosa regrowth and residual.Scanning electron microscope showed the transitional cells of neobladder were complete and orderly,and the urothelium around suture border was continuous and showed no malposition. Conclusions Reconstruction of bladder by autologous peritoneum and ileal seromuscular flaps is an ideal approach in the experimental pigs as it can prevent regrowth of ileal epithelial cells and avoid the complications of conventional enterocystoplasty.Its clinical application deserves further investigations.


Subject(s)
Ileum , Peritoneum , Urinary Bladder Neoplasms , Animals , Cystectomy , Female , Postoperative Complications , Surgical Flaps , Swine
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