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1.
Phys Rev Lett ; 132(9): 096201, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489654

RESUMO

In conventional sliding electrical contacts (SECs), large critical current density (CCD) requires a high ratio between actual and apparent contact area, while low friction and wear require the opposites. Structural superlubricity (SSL) has the characteristics of zero wear, near zero friction, and all-atoms in real contact between the contacting surfaces. Here, we show a measured current density up to 17.5 GA/m^{2} between microscale graphite contact surfaces while sliding under ambient conditions. This value is nearly 146 times higher than the maximum CCD of other SECs reported in literatures (0.12 GA/m^{2}). Meanwhile, the coefficient of friction for the graphite contact is less than 0.01 and the sliding interface is wear-free according to the Raman characterization, indicating the presence of the SSL state. Furthermore, we estimate the intrinsic CCD of single crystalline graphite to be 6.69 GA/m^{2} by measuring the scaling relation of CCD. Theoretical analysis reveals that the CCD is limited by thermal effect due to the Joule heat. Our results show the great potential of the SSL contacts to be used as SECs, such as micro- or nanocontact switches, conductive slip rings, or pantographs.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38047454

RESUMO

Two-dimensional (2D) van der Waals (vdW) layered materials have attracted considerable attention due to their potential applications in various fields. Among these materials, graphite is widely employed to achieve structural superlubricity (SSL), where the interfacial friction between two solids is almost negligible and the wear is zero. However, the development of integrated SSL systems using graphite flakes still faces a major obstacle stemming from the inherent delamination-induced instability in vdW layered materials. To address this issue, we propose a nondestructive filtering technique that utilizes electrical measurement to identify robust graphite flakes without delamination. Our experimental results confirm that all the filtered graphite flakes exhibit delamination-free behavior after more than 7000 cycles of sliding on a series of 2D and 3D substrates. Besides, we employ three types of characterizing methods to confirm that the filtering process does not impair the graphite flakes. Moreover, with focused ion beam (FIB) assisted slicing characterization and statistical analysis, we have discovered that all of the filtered flakes possess a graphite layer thickness below 100 nm. This is consistent with the thickness of the single crystalline graphite layer of our samples reported in the literature, suggesting the absence of incommensurate interfaces in the filtered graphite flakes. Our work contributes to a deeper understanding of the relationship between graphite conductance and incommensurate interfaces. In addition, we present a possible solution to address the delamination problem in layered materials, and this technique shows the potential to characterize the internal microstructure of grains and the distribution of grain boundaries in vdW materials on a large scale.

3.
Sci Rep ; 12(1): 21467, 2022 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-36509838

RESUMO

Although immunotherapy has revolutionized bladder cancer (BLCA) therapy, only few patients demonstrate durable clinical benefits due to the heterogeneity. Emerging evidence has linked pyroptosis to shaping tumor microenvironment (TME) and predicting therapy response. However, the relationship between pyroptosis and immunotherapy response in BLCA remains elusive. In this study, we performed a comprehensive bioinformatic analysis to dissect the role of pyroptosis in BLCA. Differentially expressed pyroptosis-related genes (DEPRGs) between tumor and normal tissues were identified using publicly available datasets. Kaplan-Meier analysis was performed to screen for DEPRGs associated with survival. Consensus clustering was used for BLCA subtyping. TME characteristics were evaluated by CIBERSORT, ESTIMATE and immune checkpoint genes (ICGs). Following univariate COX regression and LASSO analyses with pyroptosis-related DEGs, the risk model and nomogram were constructed with TCGA dataset and validated in the GEO dataset. Furthermore, therapeutic responses in high- and low-risk groups were compared using TIDE and GDSC databases. Two pyroptosis-related subtypes (Cluster 1 and 2) were identified based on expression patterns of GSDMA and CHMP4C. Bioinformatic analyses showed that cluster 1 had poor survival, more M0/M1/M2 macrophages, higher immune/stromal/ESTIMATE scores, and higher expression levels of ICGs. A 15-gene signature for predicting prognosis could classify patients into high- and low-risk groups. Furthermore, the correlation of risk scores with TIDE score and IC50 showed that patients in low-risk group were more sensitive to immunotherapy, whereas patients in high-risk group could better benefit from chemotherapy. Our study identified two novel pyroptosis-related subtypes and constructed a risk model, which can predict the prognosis, improve our understanding the role of PRGs in BLCA, and guide chemotherapy and immunotherapy.


Assuntos
Microambiente Tumoral , Neoplasias da Bexiga Urinária , Humanos , Microambiente Tumoral/genética , Imunoterapia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Bexiga Urinária , Nomogramas , Prognóstico , Proteínas Citotóxicas Formadoras de Poros
4.
Front Oncol ; 12: 889028, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35965513

RESUMO

Recurrence of urothelial carcinoma in a patient with solitary kidney is always a clinical challenge. In the immune checkpoint inhibitor era, neoadjuvant immunotherapy in combination with the Yang-Monti technique might be a good option for the patient with a high-risk tumor when kidney-sparing surgery for renal function preservation is desired. We report the case of a 74-year-old man with solitary kidney who was diagnosed with recurrence of urothelial carcinoma in the right ureter. He was initially deemed unfit for segmental resection of the ureter. Neoadjuvant immunotherapy with tislelizumab was performed in this patient with a partial response to urothelial carcinoma. He underwent segmental resection of the ureter with negative margins, and the ureteral defect was bridged by modified ileal replacement, which is the Yang-Monti technique. This patient has remained disease-free with adequate kidney function for longer than 18 months.

5.
Urol Case Rep ; 41: 101981, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34976739

RESUMO

Collecting duct carcinoma (CDC) is a rare form of renal carcinoma that has a poor prognosis. To date, there has been no report that the survival time of a patient with metastatic CDC could be more than six years. We present a case of rapidly advanced recurrence of CDC after nephrectomy that completely responded surgical intervention followed by targeted therapy with sorafenib and nivolumab.

6.
Zhonghua Nan Ke Xue ; 20(9): 816-9, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25306810

RESUMO

OBJECTIVE: To investigate the safety and efficiency of the disposable circumcision suture device (DCSD) in the surgical treatment of phimosis and redundant prepuce. METHODS: We randomly assigned 249 outpatients with phimosis or redundant prepuce to be treated with DCSD (n = 129) and by conventional circumcision (CC, n = 120), respectively. Then we compared the safety and efficiency of the two strategies. RESULTS: Comparisons between DCSD and CC showed that the operation time was (4.02 +/- 0.69) vs (30.8 +/- 4.05) min, blood loss was (1.07 +/- 1.29) vs (8.72 +/- 2.15) ml, intraoperative pain score was 0.81 +/- 0.81 vs 2.42 +/- 1.15, 24-hour postoperative pain score was 1.84 +/- 1.02 vs 4.99 +/- 1.36, postoperative complication rate was 13. 95% (18/129) vs 9.17% (11/120), wound healing time was (13.99 +/- 9.06) vs (17.48 +/- 3.49) d, satisfaction with the penile appearance was 98.4% (127/129) vs 95% (109/120), and treatment cost was (2215.62 +/- 17.67) vs (576.47 + 15.58) Y RMB. DCSD exhibited obvious superiority over CC for shorter operation time, less blood loss, milder intraoperative pain, sooner wound healing, and better penile appearance, but it also had a higher rate of postoperative complications (P > 0.05) and involved more treatment cost than the latter (P < 0.05). CONCLUSION: The disposable circumcision suture device affords ideal clinical effects and therefore deserves clinical popularization.


Assuntos
Circuncisão Masculina/instrumentação , Fimose/cirurgia , Grampeadores Cirúrgicos , Equipamentos Descartáveis , Seguimentos , Humanos , Masculino , Resultado do Tratamento
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