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1.
Apoptosis ; 29(5-6): 785-798, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38517601

RESUMO

Osteoarthritis (OA) is a common disease in middle-aged and elderly people. An imbalance in calcium ion homeostasis will contribute to chondrocyte apoptosis and ultimately lead to the progression of OA. Transient receptor potential channel 4 (TRPV4) is involved in the regulation of intracellular calcium homeostasis. TRPV4 is expressed in primary cilia, which can sense mechanical stimuli from outside the cell, and its abnormal expression is closely related to the development of OA. Low-intensity pulsed ultrasound (LIPUS) can alleviate chondrocyte apoptosis while the exact mechanism is unclear. In this project, with the aim of revealing the mechanism of action of LIPUS, we proposed to use OA chondrocytes and animal models, LIPUS intervention, inhibition of primary cilia, use TRPV4 inhibitors or TRPV4 agonist, and use Immunofluorescence (IF), Immunohistochemistry (IHC), Western Blot (WB), Quantitative Real-time PCR (QP) to detect the expression of cartilage synthetic matrix and endoplasmic reticulum stress markers. The results revealed that LIPUS altered primary cilia expression, promoted synthetic matrix metabolism in articular chondrocytes and was associated with primary cilia. In addition, LIPUS exerted a active effect on OA by activating TRPV4, inducing calcium inward flow, and facilitating the entry of NF-κB into the nucleus to regulate synthetic matrix gene transcription. Inhibition of TRPV4 altered primary cilia expression in response to LIPUS stimulation, and knockdown of primary cilia similarly inhibited TRPV4 function. These results suggest that LIPUS mediates TRPV4 channels through primary cilia to regulate the process of knee osteoarthritis in mice.


Assuntos
Condrócitos , Cílios , Osteoartrite do Joelho , Canais de Cátion TRPV , Animais , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética , Cílios/metabolismo , Cílios/patologia , Camundongos , Condrócitos/metabolismo , Condrócitos/patologia , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/terapia , Apoptose/genética , Progressão da Doença , Camundongos Endogâmicos C57BL , Masculino , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Modelos Animais de Doenças , Cálcio/metabolismo , Estresse do Retículo Endoplasmático , Humanos
2.
Small ; : e2309391, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456381

RESUMO

As p-type phase-change degenerate semiconductors, crystalline and amorphous germanium telluride (GeTe) exhibit metallic and semiconducting properties, respectively. However, the massive structural defects and strong interface scattering in amorphous GeTe films significantly reduce their performance. In this work, two-dimensional (2D) p-type GeTe nanosheets are synthesized via a specially designed space-confined chemical vapor deposition (CVD) method, with the thickness of the GeTe nanosheets reduced to 1.9 nm. The space-confined CVD method improves the crystallinity of ultrathin GeTe by lowering the partial pressure of the reactant gas, resulting in GeTe nanosheets with excellent p-type semiconductor properties, such as a satisfactory on/off ratio of 105 . Temperature-dependent electrical measurements demonstrate that variable-range hopping and optical-phonon-assisted hopping mechanisms dominate transport behavior at low and high temperatures, respectively. GeTe devices exhibit significantly high responsivity (6589 and 2.2 A W-1 at 633 and 980 nm, respectively) and detectivity (1.67 × 1011 and 1.3 × 108 Jones at 633 and 980 nm, respectively), making them feasible for broadband photodetectors in the visible to near-infrared range. Furthermore, the fabricated GeTe/WS2 diode exhibits a rectification ratio of 103 at zero gate voltage. These satisfactory p-type semiconductor properties demonstrate that ultrathin GeTe exhibits enormous potential for applications in optoelectronic interconnection circuits.

3.
Inorg Chem ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922608

RESUMO

The oxygen reduction reaction (ORR) plays a vital role in many next-generation electrochemical energy conversion and storage devices, motivating the search for low-cost ORR electrocatalysts possessing high activity and excellent durability. In this work, we demonstrate that iron-cobalt phosphide (FeCoP) nanoparticles encapsulated in a N-doped carbon framework (FeCoP@NC) represent a very promising catalyst for the ORR in alkaline media. The core-shell structured FeCoP@NC catalyst offered outstanding ORR activity with a half-wave potential (E1/2) of 0.86 V vs reversible hydrogen electrode (RHE) and excellent stability in a 0.1 M KOH electrolyte, outperforming commercial Pt/C and many recently reported noble-metal-free ORR electrocatalysts. The superiority of FeCoP@NC as an ORR electrocatalyst relative to Pt/C was further verified in prototype zinc-air batteries (ZABs), with the aqueous and flexible ZABs prepared using FeCoP@NC offering excellent stability, impressive open circuit voltages (1.56 and 1.44 V, respectively), and high maximum power densities (183.5 and 69.7 mW cm-2, respectively). Density functional theory calculations revealed that encapsulating FeCoP nanoparticles in N-doped carbon shells resulted in favorable electron penetration effects, which synergistically regulated the adsorption/desorption of ORR intermediates for optimal ORR performance while also boosting the electronic conductivity. Our findings offer valuable new insights for rational design of transition metal phosphide-based catalysts for the ORR and other electrochemical applications.

4.
Langenbecks Arch Surg ; 408(1): 315, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37584830

RESUMO

BACKGROUND: The prognostic significance of lymph node ratio (LNR) in N1b papillary thyroid cancer is unclear. Therefore, the impact of LNR on disease-specific mortality (DSM) and overall survival (OS) in patients with N1b papillary thyroid cancer (PTC) needs to be defined. METHODS: We used the Surveillance, Epidemiology, and End Results (SEER) database of patients who had undergone thyroidectomy and lymph node dissection. Factors associated with DSM and OS were analyzed and identified using univariate and multivariate Cox proportional risk models. X-tile software was used to find the best cutoff value of LNR. Kaplan-Meier estimates for DSM were plotted for LNR and were compared with the log-rank test. The ROC curve evaluated the validity of the model. RESULTS: A total of 3223 patients with N1b PTC were identified in the SEER database between 1975 and 2019. The best cutoff value for LNR was 0.6. The multivariate Cox proportional risk model showed that age, race, T3/T4 classification, distant metastasis, extent of surgery, number of metastatic lymph nodes, and LNR > 0.6 were independent risk factors for DSM (all p < 0.05). Age, sex, T4 classification, distant metastasis, extent of surgery, and LNR > 0.6 were independent risk factors for OS (all p < 0.05). The Kaplan-Meier method plotted a cumulative risk curve and showed that patients with LNR > 0.6 had a significantly higher risk of DSM than patients with LNR ≤ 0.6 (p = 0.002). CONCLUSION: LNR was a powerful predictor of DSM and OS in N1b PTC patients. LNR could be a useful tool for the stratification of PTC patients with lateral neck metastases.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/cirurgia , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Razão entre Linfonodos , Metástase Linfática/patologia , Linfonodos/patologia , Prognóstico , Estudos Retrospectivos , Estadiamento de Neoplasias
5.
Nano Lett ; 22(5): 2112-2119, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35226511

RESUMO

Transition metal dichalcogenide monolayers exhibit ultrahigh surface sensitivity since they expose all atoms to the surface and thereby influence their optoelectronic properties. Here, we report an intriguing lightening of the photoluminescence (PL) from the edge to the interior over time in the WS2 monolayers grown by physical vapor deposition method, with the whole monolayer brightened eventually. Comprehensive optical studies reveal that the PL enhancement arises from the p doping induced by oxygen adsorption. First-principles calculations unveil that the dissociation of chemisorbed oxygen molecule plays a significant role; i.e., the dissociation at one site can largely promote the dissociation at a nearby site, facilitating the photoluminescence lightening. In addition, we further manipulate such PL brightening rate by controlling the oxygen concentration and the temperature. The presented results uncover the extraordinary surface chemistry and related mechanism in WS2 monolayers, which deepens our insight into their unique PL evolution behavior.

6.
Small ; 18(48): e2204553, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36135974

RESUMO

Growth of semiconductor heterojunction nanoarrays directly on conductive substrates represents a promising strategy toward high-performance photoelectrodes for photoelectrochemical (PEC) water splitting. By controlling the growth conditions, heterojunction nanoarrays with different morphologies and semiconductor components can be fabricated, resulting in greatly enhanced light-absorption properties, stabilities, and PEC activities. Herein, recent progress in the development of self-supported heterostructured semiconductor nanoarrays as efficient photoanode catalysts for water oxidation is reviewed. Synthetic methods for the fabrication of heterojunction nanoarrays with specific compositions and structures are first discussed, including templating methods, wet chemical syntheses, electrochemical approaches and chemical vapor deposition (CVD) methods. Then, various heterojunction nanoarrays that have been reported in recent years based on particular core semiconductor scaffolds (e.g., TiO2 , ZnO, WO3 , Fe2 O3 , etc.) are summarized, placing strong emphasis on the synergies generated at the interface between the semiconductor components that can favorably boost PEC water oxidation. Whilst strong progress has been made in recent years to enhance the visible-light responsiveness, photon-to-O2 conversion efficiency and stability of photoanodes based on heterojunction nanoarrays, further advancements in all these areas are needed for PEC water splitting to gain any traction alongside photovoltaic-electrochemical (PV-EC) systems as a viable and cost-effective route toward the hydrogen economy.


Assuntos
Semicondutores , Água , Gases , Hidrogênio , Condutividade Elétrica
7.
Inorg Chem ; 61(48): 19624-19632, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36383489

RESUMO

We, for the first time, offer a unique and disruptive strategy to prepare N-doped three-dimensional porous carbon framework-supported well-defined Fe4[Fe(CN)6]3 nanocubes (indicated as PB@N-PCFs). The carbon frameworks hold an ultrawide interlayer spacing of 0.385-0.402 nm for the (002) planes of graphite and ultrahigh graphitization. Furthermore, PB@N-PCFs are used as a carrier to grow NiFe-layered-double-hydroxide nanosheet arrays (denoted as NiFe-LDH/PB@N-PCFs) in situ, where the interlayer spacing for the (002) planes of graphite can be expanded as high as 0.457 nm in the carbon frameworks. Moreover, NiFe-LDH/PB@N-PCFs shows excellent electrocatalytic performance toward oxygen evolution in terms of activity, kinetics, and durability, elegantly rivaling the state-of-the-art RuO2. More profoundly, after 3000 cycle cyclic voltammetry scans, NiFe-LDH/PB@N-PCFs still display far more desirable activity with respect to initial NiFe-LDH/PB@N-PCFs. We believe that the PB@N-PCFs and PB@N-PCFs-based composites with ultrahighly graphitized and large interlayer spacing N-PCFs can find more places in electrochemistry-related applications such as Na/K-ion batteries, electrocatalysis, and electrochemical sensors.

8.
Langenbecks Arch Surg ; 407(4): 1647-1652, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35146548

RESUMO

PURPOSE: Extensive lymph node metastasis (ELM) can occur in some patients with T1 papillary thyroid cancer (PTC). However, the risk factors for ELM in patients with T1 PTC have not been fully explored. In this study, we aimed to examine the association between extranodal extension (ENE) and ELM in patients with T1 PTC. PATIENTS AND METHODS: We identified 645 consecutive patients who had T1 PTC initially resected at our centre. Clinical and pathological data were reviewed. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for ELM. RESULTS: ELM was identified in 3.9% of T1 PTC patients, and ENE was identified in 8.1% of patients. ENE was associated with male sex, large tumour size, more positive nodes, and comprehensive surgical treatment. In multivariate analysis, three variables were independently associated with ELM, including ENE (odds ratio [OR], 11.15; 95% confidence interval [CI], 4.54 to 27.30; P < 0.001), age (OR, 0.96; 95% CI, 0.93 to 0.99; P = 0.022), and tumour size (OR, 1.18; 95% CI, 1.06 to 1.31; P = 0.002). Bilateral multifocality and sex were not independently associated with ELM. CONCLUSION: ENE is a strong independent predictor of ELM in patients with T1 PTC. Patients with ENE-positive nodes might need extensive neck dissection.


Assuntos
Carcinoma Papilar , Carcinoma , Neoplasias da Glândula Tireoide , Carcinoma/cirurgia , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Extensão Extranodal , Humanos , Linfonodos/patologia , Metástase Linfática/patologia , Masculino , Esvaziamento Cervical , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia
9.
Proc Natl Acad Sci U S A ; 116(27): 13404-13413, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31213539

RESUMO

BRUCE/Apollon is a membrane-associated inhibitor of apoptosis protein that is essential for viability and has ubiquitin-conjugating activity. On initiation of apoptosis, the ubiquitin ligase Nrdp1/RNF41 promotes proteasomal degradation of BRUCE. Here we demonstrate that BRUCE together with the proteasome activator PA28γ causes proteasomal degradation of LC3-I and thus inhibits autophagy. LC3-I on the phagophore membrane is conjugated to phosphatidylethanolamine to form LC3-II, which is required for the formation of autophagosomes and selective recruitment of substrates. SIP/CacyBP is a ubiquitination-related protein that is highly expressed in neurons and various tumors. Under normal conditions, SIP inhibits the ubiquitination and degradation of BRUCE, probably by blocking the binding of Nrdp1 to BRUCE. On DNA damage by topoisomerase inhibitors, Nrdp1 causes monoubiquitination of SIP and thus promotes apoptosis. However, on starvation, SIP together with Rab8 enhances the translocation of BRUCE into the recycling endosome, formation of autophagosomes, and degradation of BRUCE by optineurin-mediated autophagy. Accordingly, deletion of SIP in cultured cells reduces the autophagic degradation of damaged mitochondria and cytosolic protein aggregates. Thus, by stimulating proteasomal degradation of LC3-I, BRUCE also inhibits autophagy. Conversely, SIP promotes autophagy by blocking BRUCE-dependent degradation of LC3-I and by enhancing autophagosome formation and autophagic destruction of BRUCE. These actions of BRUCE and SIP represent mechanisms that link the regulation of autophagy and apoptosis under different conditions.


Assuntos
Autofagia , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Animais , Apoptose , Autofagossomos/metabolismo , Dano ao DNA , Fibroblastos , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Camundongos , Ubiquitinação
10.
Nano Lett ; 21(8): 3426-3434, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33872022

RESUMO

High-index semiconductor nanoantennae represent a powerful platform for nonlinear photon generation. Devices with reduced footprints are pivotal for higher integration capacity and energy efficiency in photonic integrated circuitry (PIC). Here, we report on a deep subwavelength nonlinear antenna based on dilute nitride GaNP nanowires (NWs), whose second harmonic generation (SHG) shows a 5-fold increase by incorporating ∼0.45% of nitrogen (N), in comparison with GaP counterpart. Further integrating with a gold (Au) thin film-based hybrid cavity achieves a significantly boosted SHG output by a factor of ∼380, with a nonlinear conversion efficiency up to 9.4 × 10-6 W-1. In addition, high-density zinc blende (ZB) twin phases were found to tailor the nonlinear radiation profile via dipolar interference, resulting in a highly symmetric polarimetric pattern well-suited for coupling with polarization nano-optics. Our results manifest dilute nitride nanoantenna as promising building blocks for future chip-based nonlinear photonic technology.

11.
Nano Lett ; 15(1): 80-7, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25495154

RESUMO

Topological insulators (TIs) are a new type of electronic materials in which the nontrivial insulating bulk band topology governs conducting boundary states with embedded spin-momentum locking. Such edge states are more robust in a two-dimensional (2D) TI against scattering by nonmagnetic impurities than in its three-dimensional (3D) variant, because in 2D the two helical edge states are protected from the only possible backscattering. This makes the 2D TI family a better candidate for coherent spin transport and related applications. While several 3D TIs are already synthesized experimentally, physical realization of 2D TI is so far limited to hybrid quantum wells with a tiny bandgap that does not survive temperatures above 10 K. Here, combining first-principles calculations and scanning tunneling microscopy/spectroscopy (STM/STS) experimental studies, we report nontrivial 2D TI phases in 2-monolayer (2-ML) and 4-ML Bi(110) films with large and tunable bandgaps determined by atomic buckling of Bi(110) films. The gapless edge states are experimentally detected within the insulating bulk gap at 77 K. The band topology of ultrathin Bi(110) films is sensitive to atomic buckling. Such buckling is sensitive to charge doping and could be controlled by choosing different substrates on which Bi(110) films are grown.

12.
Tissue Eng Regen Med ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842768

RESUMO

BACKGROUND: The therapeutic potential of exosomes from human umbilical cord mesenchymal stem cells (HUMSCs-Exo) for delivering specific circular RNAs (circRNAs) in treating premature ovarian failure (POF) is not well understood. This study aimed to explore the efficacy of HUMSCs-Exo in delivering hsa_circ_0002021 for POF treatment, focusing on its effects on granulosa cell (GC) senescence and ovarian function. METHODS: Bioinformatic analysis was conducted on circRNA profiles using the GSE97193 dataset from GEO, targeting granulosa cells from varied age groups. To simulate granulosa cell senescence, KGN cells were treated with cyclophosphamide (CTX). HUMSCs were transfected with pcDNA 3.1 vectors to overexpress hsa_circ_0002021, and the HUMSCs-Exo secreted were isolated. These exosomes were characterized by transmission electron microscopy (TEM) and Western blotting to confirm exosomal markers CD9 and CD63. Co-culture of these exosomes with CTX-treated KGN cells was performed to assess ß-galactosidase activity, oxidative stress markers, ROS levels, and apoptosis via flow cytometry. Interaction between hsa_circ_0002021, microRNA-125a-5p (miR-125a-5p), and cyclin-dependent kinase 6 (CDK6) was investigated using dual-luciferase assays and RNA immunoprecipitation (RIP). A POF mouse model was induced with CTX, treated with HUMSCs-Exo, and analyzed histologically and via immunofluorescence staining. Gene expression was quantified using RT-qPCR and Western blot. RESULTS: hsa_circ_0002021 was under expressed in both in vivo and in vitro POF models and was effectively delivered by HUMSCs-Exo to KGN cells, showing a capability to reduce GC senescence. Overexpression of hsa_circ_0002021 in HUMSCs-Exo significantly enhanced these anti-senescence effects. This circRNA acts as a competitive adsorbent of miR-125a-5p, regulating CDK6 expression, which is crucial in modulating cell cycle and apoptosis. Enhanced expression of hsa_circ_0002021 in HUMSCs-Exo ameliorated GC senescence in vitro and improved ovarian function in POF models by modulating oxidative stress and cellular senescence markers. CONCLUSION: This study confirms that hsa_circ_0002021, when delivered through HUMSCs-Exo, can significantly mitigate GC senescence and restore ovarian function in POF models. These findings provide new insights into the molecular mechanisms of POF and highlight the therapeutic potential of circRNA-enriched exosomes in treating ovarian aging and dysfunction.

13.
Adv Mater ; 36(14): e2312425, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38146671

RESUMO

2D transition metal dichalcogenides (TMDCs) are considered as promising materials in post-Moore technology. However, the low photoluminescence quantum yields (PLQY) and single carrier polarity due to the inevitable defects during material preparation are great obstacles to their practical applications. Here, an extraordinary defect engineering strategy is reported based on first-principles calculations and realize it experimentally on WS2 monolayers by doping with IIIA atoms. The doped samples with large sizes possess both giant PLQY enhancement and effective carrier polarity modulation. Surprisingly, the high PL emission maintained even after one year under ambient environment. Moreover, the constructed p-n homojunctions shows high rectification ratio (≈2200), ultrafast response times and excellent stability. Meanwhile, the doping strategy is universally applicable to other TMDCs and dopants. This smart defect engineering strategy not only provides a general scheme to eliminate the negative influence of defects, but also utilize them to achieve desired optoelectronic properties for multifunctional applications.

14.
Oral Oncol ; 146: 106563, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37690364

RESUMO

OBJECTIVES: To investigate the impact of the lymph node ratio (LNR) on postoperative thyroglobulin (Tg) levels in patients with papillary thyroid carcinoma (PTC). PATIENTS AND METHODS: This was a retrospective, cohort study. The association between clinicopathological variables and postoperative unstimulated Tg (uTg) levels, preablative-stimulated Tg (sTg) levels, and postablative unstimulated Tg levels was analysed. RESULTS: A total of 300 patients with PTC were identified. Multivariate logistic analysis showed that M classification (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.62-3.34), and postoperative thyroid-stimulating hormone levels (OR, 1.01; 95% CI, 1.01-1.02) were independently associated with postoperative uTg levels. One hundred and sixteen patients underwent radioactive iodine (RAI) therapy. Multivariate analysis showed that LNR in the central neck (OR, 1.24; 95% CI, 1.02-1.51), LNR in the lateral neck (OR, 1.73; 95% CI, 1.09-2.77), RAI dose (OR, 1.43; 95% CI, 1.21-1.69), and M classification (OR, 1.79; 95% CI, 1.22-2.61) were independently associated with preablative sTg levels. Tumour size (OR, 1.01; 95% CI, 1.00-1.01), LNR in the central neck (OR, 1.28; 95% CI, 1.08-1.51), LNR in the lateral neck (OR, 1.66; 95% CI, 1.10-2.49), RAI dose (OR, 1.54; 95% CI, 1.34-1.79), and M classification (OR, 1.56; 95% CI, 1.12-2.19) were also independently associated with postablative uTg levels. CONCLUSION: LNR was independently associated with postoperative Tg levels in patients with PTC. Patients with high LNR were more likely to have incomplete biochemical responses after surgery.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Papilar/cirurgia , Carcinoma Papilar/patologia , Estudos de Coortes , Radioisótopos do Iodo/uso terapêutico , Razão entre Linfonodos , Linfonodos/patologia , Estudos Retrospectivos , Tireoglobulina/sangue , Tireoglobulina/química , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia
15.
Cells ; 12(18)2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37759433

RESUMO

Autophagy is critical to acrosome biogenesis and mitochondrial quality control, but the underlying mechanisms remain unclear. The ubiquitin ligase Nrdp1/RNF41 promotes ubiquitination of the mitophagy-associated Parkin and interacts with the pro-autophagic protein SIP/CacyBP. Here, we report that global deletion of Nrdp1 leads to formation of the round-headed sperm and male infertility by disrupting autophagy. Quantitative proteome analyses demonstrated that the expression of many proteins associated with mitochondria, lysosomes, and acrosomes was dysregulated in either spermatids or sperm of the Nrdp1-deficient mice. Deletion of Nrdp1 increased the levels of Parkin but decreased the levels of SIP, the mitochondrial fission protein Drp1 and the mitochondrial protein Tim23 in sperm, accompanied by the inhibition of autophagy, the impairment of acrosome biogenesis and the disruption of mitochondrial arrangement in sperm. Thus, our results uncover an essential role of Nrdp1 in spermiogenesis and male fertility by promoting autophagy, providing important clues to cope with the related male reproductive diseases.


Assuntos
Acrossomo , Espermatogênese , Ubiquitina-Proteína Ligases , Animais , Masculino , Camundongos , Autofagia , Mitocôndrias/metabolismo , Sêmen/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
16.
Nanoscale ; 15(9): 4438-4447, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36752096

RESUMO

Low-dimensional group IV-VI metal chalcogenide-based semiconductors hold great promise for opto-electronic device applications owing to their diverse crystalline phases and intriguing properties related to thermoelectric and ferroelectric effects. Herein, we demonstrate a universal chemical vapor deposition (CVD) growth method to synthesize stable germanium chalcogenide-based (GeS, GeS2, GeSe, GeSe2) nanosheets, which increases the library of the p-type semiconductor. The phase transition between different crystalline polytypes can be deterministically controlled by hydrogen concentration in the reaction chamber. Structural characterization and synthesis experiments identify the behavior, where the higher hydrogen concentration promotes the transiton from germanium dichalcogenides to germanium monochalcogenides. The angle-polarized and temperature-dependent Raman spectra demonstrate the strong interlayer coupling and lattice orientation. Based on the optimized growth scheme and systematic comparison of electrical properties, GeSe nanosheet photodetectors were demonstrated, which exhibit superior device performance on SiO2/Si and HfO2/Si substrate with a high photoresponsivity up to 104 A W-1, fast response time less than 15 ms, and high mobility of 3.2 cm2 V-1 s-1, which is comparable to the mechanically exfoliated crystals. Our results manifest the hydrogen-mediated deposition strategy as a facile control knob to engineer crystalline phases of germanium chalcogenides for high performance optoelectronic devices.

17.
J Phys Chem Lett ; 14(7): 1740-1747, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36758156

RESUMO

PtNi nanoalloys have demonstrated electrocatalysis superior to that of benchmark Pt/C catalysts for the oxygen reduction reaction (ORR), yet the underlying mechanisms remain underexplored. Herein, a PtNi/NC catalyst comprising PtNi nanoparticles (∼5.2 nm in size) dispersed on N-doped carbon frameworks was prepared using a simple pyrolysis strategy. Benefiting from the individual components and a hierarchical structure, the PtNi/NC catalyst exhibited outstanding ORR activity and stability (E1/2 = 0.82 V vs RHE and 8 mV negative shift after 20000 cycles), outperforming a commercial 20 wt % Pt/C catalyst (E1/2 = 0.81 V and 32 mV negative shift). A prototype zinc-air battery constructed using PtNi/NC as the air electrode catalyst achieved highly enhanced electrochemical performance, outperforming a battery constructed using Pt/C as the ORR catalyst. Density functional theory calculations revealed that the improved ORR activity of the PtNi nanoalloys originated from charge redistribution with a suitable metal d-band center to promote the formation of the ORR intermediates.

18.
J Phys Chem Lett ; 14(26): 6099-6109, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37364134

RESUMO

Herein, a simple two-step synthetic method was developed for the synthesis of NiFe2O4 nano-microrods supported on Ketjenblack carbon (NiFe2O4/KB). A sodium tartrate-assisted hydrothermal method was employed for the synthesis of a NiFe-MOF/KB precursor, which was then pyrolyzed under N2 at 500 °C to yield NiFe2O4/KB. Benefiting from the presence of high-valence Ni3+ and Fe3+, high conductivity, and a large electrochemically active surface area, NiFe2O4/KB delivered outstanding OER electrocatalytic performance under alkaline conditions, including a very low overpotential of 258 mV (vs RHE) at 10 mA cm-2, a small Tafel slope of 43.01 mV dec-1, and excellent durability in 1.0 M KOH. Density functional theory calculations verified the superior alkaline OER electrocatalytic activity of NiFe2O4 to IrO2. While both catalysts possessed a similar metallic ground state, NiFe2O4 offered a lower energy barrier in the rate-determining OER step (*OOH → O2) compared to IrO2, resulting in faster OER kinetics.

19.
Endocrine ; 78(3): 484-490, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36018538

RESUMO

BACKGROUND: The purpose of this study was to explore the impact of the lymph node ratio on prognosis in papillary thyroid cancer patients with lymph node metastasis. METHODS: Data from papillary thyroid cancer patients with positive nodes who were initially treated at our institution during 2015-2016 were analysed. Univariate and multivariate Cox proportional hazard models were adopted to predict prognostic factors. A receiver operating characteristic (ROC) curve was used to find the best cut-off value of the lymph node ratio (LNR). Kaplan-Meier curves were used to show the relationship between the LNR in the lateral neck and recurrence-free survival. RESULTS: The median follow-up time was 64.6 months, and recurrence occurred in 16 of 662 patients (2.27%). Univariate analysis showed that male sex, primary tumour size (>17 mm), visible extrathyroidal extension, LNR in the central neck (>0.5), LNR in the lateral neck (>0.10), and visible extranodal extension were significantly correlated with recurrence-free survival (RFS) (p < 0.05). Multivariate analysis using the Cox proportional hazards model showed that the LNR in the lateral neck was an independent risk factor for RFS (p = 0.039; HR 14.76). CONCLUSION: The LNR in the lateral neck was an independent risk factor for recurrence-free survival. For patients with a high lymph node ratio in the lateral neck, more frequent follow-up might be needed.


Assuntos
Esvaziamento Cervical , Neoplasias da Glândula Tireoide , Humanos , Masculino , Câncer Papilífero da Tireoide/patologia , Razão entre Linfonodos , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia , Linfonodos/patologia , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Prognóstico , Fatores de Risco , Estadiamento de Neoplasias
20.
Front Oncol ; 12: 993725, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36544713

RESUMO

Medullary thyroid carcinoma (MTC) is one of the common malignant endocrine tumors, which seriously affects human health. Although surgical resection offers a potentially curative therapeutic option to some MTC patients, most patients do not benefit from it due to the difficulty to access the tumors and tumor metastasis. The survival rate of MTC patients has improved with the recent advances in the research, which has improved our understanding of the molecular mechanism underlying MTC and enabled the development and approval of novel targeted drugs. In this article, we reviewed the molecular mechanisms related to MTC progression and the principle for the design of molecular targeted drugs, and proposed some future directions for prospective studies exploring targeted drugs for MTC.

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