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1.
Front Immunol ; 15: 1384548, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533512

RESUMO

Introduction: Colorectal cancer (CRC) presents a substantial challenge characterized by unacceptably high mortality and morbidity, primarily attributed to delayed diagnosis and reliance on palliative care. The immune response of the host plays a pivotal role in carcinogenesis, with IL-38 emerging as a potential protective factor in CRC. However, the precise involvement of IL-38 among various leucocytes, its interactions with PD-1/PD-L1, and its impact on metastasis require further elucidation. Results: Our investigation revealed a significant correlation between IL-38 expression and metastasis, particularly concerning survival and interactions among diverse leucocytes within draining lymph nodes. In the mesentery lymph nodes, we observed an inverse correlation between IL-38 expression and stages of lymph node invasions (TNM), invasion depth, distance, and differentiation. This aligns with an overall survival advantage associated with higher IL-38 expression in CRC patients' nodes compared to lower levels, as well as elevated IL-38 expression on CD4+ or CD8+ cells. Notably, a distinct subset of patients characterized by IL-38high/PD-1low expression exhibited superior survival outcomes compared to other combinations. Discussion: Our findings demonstrate that IL-38 expression in colorectal regional nodes from CRC patients is inversely correlated with PD-1/PD-L1 but positively correlated with infiltrating CD4+ or CD8+ lymphocytes. The combined assessment of IL-38 and PD-1 expression in colorectal regional nodes emerges as a promising biomarker for predicting the prognosis of CRC.


Assuntos
Antígeno B7-H1 , Neoplasias Colorretais , Humanos , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Antígeno CTLA-4/metabolismo , Relevância Clínica , Fatores de Transcrição Forkhead/metabolismo , Linfonodos , Interleucinas/metabolismo
2.
J Adv Res ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38554999

RESUMO

INTRODUCTION: Osteoarthritis (OA) is a progressive disease that poses a significant threat to human health, particularly in aging individuals: Although sympathetic activation has been implicated in bone metabolism, its role in the development of OA related to aging remains poorly understood. Therefore, this study aimed to investigate how sympathetic regulation impacts aging-related OA through experiments conducted both in vivo and in vitro. METHODS: To analyze the effect of sympathetic regulation on aging-related OA, we conducted experiments using various mouse models. These models included a natural aging model, a medial meniscus instability model, and a load-induced model, which were used to examine the involvement of sympathetic nerves. In order to evaluate the expression levels of ß1-adrenergic receptor (Adrß1) and sirtuin-6 (Sirt6) in chondrocytes of naturally aging OA mouse models, we performed assessments. Additionally, we investigated the influence of ß1-adrenergic receptor knockout or treatment with a ß1-adrenergic receptor blocker on the progression of OA in aging mice and detected exosome release and detected downstream signaling expression by inhibiting exosome release. Furthermore, we explored the impact of sympathetic depletion through tyrosine hydroxylase (TH) on OA progression in aging mice. Moreover, we studied the effects of norepinephrine(NE)-induced activation of the ß1-adrenergic receptor signaling pathway on the release of exosomes and miR-125 from chondrocytes, subsequently affecting osteoblast differentiation in subchondral bone. RESULTS: Our findings demonstrated a significant increase in sympathetic activity, such as NE levels, in various mouse models of OA including natural aging, medial meniscus instability, and load-induced models. Notably, we observed alterations in the expression levels of ß1-adrenergic receptor and Sirt6 in chondrocytes in OA mouse models associated with natural aging, leading to an improvement in the progression of OA. Critically, we found that the knockout of ß1-adrenergic receptor or treatment with a ß1-adrenergic receptor blocker attenuated OA progression in aging mice and the degraded cartilage explants produced more exosome than the nondegraded ones, Moreover, sympathetic depletion through TH was shown to ameliorate OA progression in aging mice. Additionally, we discovered that NE-induced activation of the ß1-adrenergic receptor signaling pathway facilitated the release of exosomes and miR-125 from chondrocytes, promoting osteoblast differentiation in subchondral bone. CONCLUSION: In conclusion, our study highlights the role of sympathetic innervation in facilitating the transfer of exosomal miR-125 from osteoarthritic chondrocytes, ultimately disrupting subchondral bone homeostasis and exacerbating cartilage damage in aging mice. These findings provide valuable insights into the potential contribution of sympathetic regulation to the pathogenesis of aging-related OA.

3.
Front Immunol ; 15: 1322256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38524127

RESUMO

Introduction: Wound healing poses a clinical challenge in diabetes mellitus (DM) due to compromised host immunity. CD64, an IgG-binding Fcgr1 receptor, acts as a pro-inflammatory mediator. While its presence has been identified in various inflammatory diseases, its specific role in wound healing, especially in DM, remains unclear. Objectives: We aimed to investigate the involvement of CD64 in diabetic wound healing using a DM animal model with CD64 KO mice. Methods: First, we compared CD64 expression in chronic skin ulcers from human DM and non-DM skin. Then, we monitored wound healing in a DM mouse model over 10 days, with or without CD64 KO, using macroscopic and microscopic observations, as well as immunohistochemistry. Results: CD64 expression was significantly upregulated (1.25-fold) in chronic ulcerative skin from DM patients compared to non-DM individuals. Clinical observations were consistent with animal model findings, showing a significant delay in wound healing, particularly by day 7, in CD64 KO mice compared to WT mice. Additionally, infiltrating CD163+ M2 macrophages in the wounds of DM mice decreased significantly compared to non-DM mice over time. Delayed wound healing in DM CD64 KO mice correlated with the presence of inflammatory mediators. Conclusion: CD64 seems to play a crucial role in wound healing, especially in DM conditions, where it is associated with CD163+ M2 macrophage infiltration. These data suggest that CD64 relies on host immunity during the wound healing process. Such data may provide useful information for both basic scientists and clinicians to deal with diabetic chronic wound healing.


Assuntos
Diabetes Mellitus Experimental , Úlcera Cutânea , Cicatrização , Animais , Camundongos , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Macrófagos/metabolismo , Pele/metabolismo , Cicatrização/genética
4.
Biomed Pharmacother ; 172: 116288, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377739

RESUMO

Synthetic lethality is a phenomenon wherein the simultaneous deficiency of two or more genes results in cell death, while the deficiency of any individual gene does not lead to cell death. In recent years, synthetic lethality has emerged as a significant topic in the field of targeted cancer therapy, with certain drugs based on this concept exhibiting promising outcomes in clinical trials. Nevertheless, the presence of tumor heterogeneity and the intricate DNA repair mechanisms pose challenges to the effective implementation of synthetic lethality. This review aims to explore the concepts, development, and ethical quandaries surrounding synthetic lethality. Additionally, it will provide an in-depth analysis of the clinical application and underlying mechanism of synthetic lethality.


Assuntos
Neoplasias , Mutações Sintéticas Letais , Morte Celular , Reparo do DNA , Neoplasias/tratamento farmacológico , Neoplasias/genética
5.
J Pathol ; 262(3): 334-346, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38180342

RESUMO

Adenocarcinoma of the bladder is a rare urinary bladder carcinoma with limited therapy options due to lack of molecular characterization. Here, we aimed to reveal the mutational and transcriptomic landscapes of adenocarcinoma of the bladder and assess any relationship with prognosis. Between February 2015 and June 2021, a total of 23 patients with adenocarcinoma of the bladder were enrolled. These included 16 patients with primary bladder adenocarcinomas and seven patients with urachal adenocarcinoma. Whole exome sequencing (16 patients), whole genome sequencing (16 patients), bulk RNA sequencing (RNA-seq) (19 patients), and single-cell RNA-seq (5 patients) were conducted for the specimens. Correlation analysis, survival analysis, and t-tests were also performed. Prevalent T>A substitutions were observed among somatic mutations, and major trinucleotide contexts included 5'-CTC-3' and 5'-CTG-3'. This pattern was mainly contributed by COSMIC signature 22 related to chemical carcinogen exposure (probably aristolochic acid), which has not been reported in bladder adenocarcinoma. Moreover, genes with copy number changes were also enriched in the KEGG term 'chemical carcinogenesis'. Transcriptomic analysis suggested high immune cell infiltration and luminal-like features in the majority of samples. Interestingly, a small fraction of samples with an APOBEC-derived mutational signature exhibited a higher risk of disease progression compared with samples with only a chemical carcinogen-related signature, confirming the molecular and prognostic heterogeneity of bladder adenocarcinoma. This study presents mutational and transcriptomic landscapes of bladder adenocarcinoma, and indicates that a chemical carcinogen-related mutational signature may be related to a better prognosis compared with an APOBEC signature in adenocarcinoma of the bladder. © 2024 The Pathological Society of Great Britain and Ireland.


Assuntos
Adenocarcinoma , Bexiga Urinária , Humanos , Bexiga Urinária/patologia , Mutação , Adenocarcinoma/genética , Adenocarcinoma/patologia , Carcinógenos , Prognóstico
6.
Nanoscale ; 15(47): 19148-19158, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37938108

RESUMO

Electrochemical oxygen reduction (ORR) for the production of clean hydrogen peroxide (H2O2) is an effective alternative to industrial anthraquinone methods. The development of highly active, stable, and 2e- ORR oxygen reduction electrocatalysts while suppressing the competing 4e- ORR pathway is currently the main challenge. Herein, bimetallic doping was successfully achieved based on graphitic carbon nitride (g-C3N4) with the simultaneous introduction of K and Co, whereby 2D porous K-Co/CNNs nanosheets were obtained. The introduction of Co promoted the selectivity for H2O2, while the introduction of K not only promoted the formation of 2D nanosheets of g-C3N4, but also inhibited the ablation of H2O2 by K-Co/CNNs. Electrochemical studies showed that the selectivity of H2O2 in K-Co/CNNs under neutral electrolyte was as high as 97%. After 24 h, the H2O2 accumulation of K-Co/CNNs was as high as 31.7 g L-1. K-Co/CNNs improved the stability of H2O2 by inhibiting the ablation of H2O2, making it a good 2e- ORR catalyst and providing a new research idea for the subsequent preparation of H2O2.

7.
Small ; : e2307040, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37967337

RESUMO

The practical application of Li-S batteries is still severely restricted by poor cyclic performance caused by the intrinsic polysulfides shuttle effect, which is even more severe under the high-temperature condition owing to the inevitable increase of polysulfides' solubility and diffusion rate. Herein, tungsten-doped vanadium dioxide (W-VO2 ) micro-flowers are employed with first-order metal-insulator phase transition (MIT) property as a robust and multifunctional modification layer to hamper the shuttle effect and simultaneously improve the thermotolerance of the common separator. Tungsten doping significantly reduces the transition temperature from 68 to 35 °C of vanadium dioxide, which renders the W-VO2 easier to turn from the insulating monoclinic phase into the metallic rutile phase. The systematic experiments and theoretical analysis demonstrate that the temperature-induced in-suit MIT property endows the W-VO2 catalyst with strong chemisorption against polysulfides, low energy barrier for liquid-to-solid conversion, and outstanding diffusion kinetics of Li-ion under high temperatures. Benefiting from these advantages, the Li-S batteries with W-VO2 modified separator exhibit significantly improved rate and long-term cyclic performance under 50 °C. Remarkably, even at an elevated temperature (80 °C), they still exhibit superior electrochemical performance. This work opens a rewarding avenue to use phase-changing materials for high-temperature Li-S batteries.

8.
Heliyon ; 9(10): e20771, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37842584

RESUMO

Objective: To compare the clinical efficacy and safety of electroacupuncture combined with extracorporeal shock wave therapy (EESWT) and extracorporeal shock wave therapy (ESWT) in the treatment of knee osteoarthritis (KOA). Methods: A total of 135 KOA patients who received EESWT treatment were selected as the EESWT group, and 135 KOA patients who received extracorporeal shock wave therapy (ESWT) were selected as the ESWT group. The clinical efficacy, inflammatory factors in joint synovial fluid and adverse events during treatment were compared before and after treatment. Results: The clinical effective rate of patients in the EESWT group (89.63 %) after treatment was significantly higher than that of the ESWT group (74.81 %) (p < 0.01). The lysholm kness (LKSS) score and range of motion (ROM) of the patients in the EESWT group after treatment were higher than those of the ESWT group, while Lequesne index score, visual analogue scale (VAS) score and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were lower than those of the ESWT group (p < 0.01). Compared with ESWT group, the changes in the expression levels of nitric oxide (NO), superoxide dismutase (SOD), interleukin 1ß (IL-1ß), tumor necrosis factor-α (TNF-α), matrix metalloproteinase-3 (MMP-3), and transforming growth factor ß1 (TGF-ß1) in the synovial fluid of the EESWT group after treatment were significantly greater than those of the ESWT group (p < 0.01). No significant difference in the incidence of adverse events between the EESWT group and the ESWT group (p > 0.05). Conclusion: EESWT significantly improves pain symptoms and inflammatory factor levels in KOA patients and is an optional KOA treatment option worthy of clinical attention.

9.
ACS Appl Mater Interfaces ; 15(40): 46971-46981, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37755826

RESUMO

The exploitation of high-performance supercapacitors is crucial to promote energy storage technologies. Benefiting from the three-dimensional conductive micronanostructures and high specific capacity of the PPy@CuCo2S4@NF (polypyrrole/copper cobalt sulfide/nickel foam) composite electrode, this electrode exhibits a high specific capacity of 1403.21 C g-1 at 1 A g-1 and a capacitance retention of 85.79% after 10,000 cycles at 10 A g-1. The assembled PPy@CuCo2S4@NF//AC aqueous hybrid supercapacitor (AHSC) reveals a wide operating potential window of 1.5 V and achieves a high specific capacity of 322.52 C g-1 at 1 A g-1 and a capacitance retention of 86.84% after 15,000 cycles at 10 A g-1. The AHSC also exhibits a high power density of 733.69 W kg-1 at an energy density of 67.19 W h kg-1, surpassing those of previously reported spinel-based supercapacitors. Ex situ X-ray diffraction and X-ray photoelectron spectroscopy results show that the CuCo2S4 spinel structure changes to CuS2 and CoS2 cube structures, and the oxidation states of Cu and Co increase during charging and discharging processes. Density functional theory calculations suggest a superior conductivity for CuCo2S4 compared to that for CuCo2O4, demonstrating that CuCo2S4 has superior electrochemical performance. These findings attest to the considerable potential of the spinel materials for advanced energy storage applications.

10.
MedComm (2020) ; 4(5): e378, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37724132

RESUMO

Uncontrolled and excessive progression of liver fibrosis is thought to be the prevalent pathophysiological cause of liver cirrhosis and hepatocellular cancer, and there are currently no effective antifibrotic therapeutic options available. Intercellular communication and cellular heterogeneity in the liver are involved in the progression of liver fibrosis, but the exact nature of the cellular phenotypic changes and patterns of interregulatory remain unclear. Here, we performed single-cell RNA sequencing on nonparenchymal cells (NPCs) isolated from normal and fibrotic mouse livers. We identified eight main types of cells, including endothelial cells, hepatocytes, dendritic cells, B cells, natural killer/T (NK/T) cells, hepatic stellate cells (HSCs), cholangiocytes and macrophages, and revealed that macrophages and HSCs exhibit the most variance in transcriptional profile. Further analyses of HSCs and macrophage subpopulations and ligand-receptor interaction revealed a high heterogeneity characterization and tightly interregulated network of these two groups of cells in liver fibrosis. Finally, we uncovered a profibrotic Thbs1+ macrophage subcluster, which expands in mouse and human fibrotic livers, activating HSCs via PI3K/AKT/mTOR signaling pathway. Our findings decode unanticipated insights into the heterogeneity of HSCs and macrophages and their intercellular crosstalk at a single-cell level, and may provide potential therapeutic strategies in liver fibrosis.

11.
ACS Appl Mater Interfaces ; 15(38): 44996-45004, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37700536

RESUMO

Transition metal sulfide (TMS) CoS2 is considered an ideal anode material for new-generation lithium-ion batteries (LIBs) because of its high specific capacity, high electrochemical activity, and low cost. However, CoS2 is prone to volume expansion and structural collapse when it participates in the internal conversion reaction of the battery, which limits its practical application. After analyzing the failure mechanism of CoS2 as the anode material of LIBs, the concept of nanoengineered materials is introduced here. CoS2 particles are nanosized and stabilized by constructing a composite structure on an alkali-treated two-dimensional Ti3C2 Mxene conductive network. Both experiments and theoretical calculations show that special Ti-O-Co bonds are formed at the interface of the Ti3C2/CoS2 composite through oxygen-containing functional groups. Ti-O-Co bonding with adjustable electronic characteristics can effectively promote the utilization rate of anode materials, electronic conductivity, and ionic diffusivity and thus enhance the redox reaction kinetics of the device. When the Ti3C2/CoS2 composite is used as the anode material for LIBs, it still provides a high specific capacity of 405.8 mAh g-1 after 100 cycles at 0.1 A g-1. After running for 1000 cycles at a high current of 1 A g-1, the capacity retention is still close to 100%. Also, high cycle stability under the condition of highly active material loading (10.58 mg cm-2) and low electrolyte/active material ratio (10 µL mg-1) is achieved. This work provides a new idea for the development of commercial LIBs as anode materials.

12.
Free Radic Biol Med ; 208: 319-333, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37640169

RESUMO

Although spinal cord injury (SCI) represents a primary etiology of disability, currently, there are exist limited viable therapies modalities. Acquiring comprehension of the diverse pathways that drive mitochondrial aberration may facilitate the identification of noteworthy targets for ameliorating the deleterious consequences precipitated by SCI. Our objective was to determine the efficiency of exosomes produced from Schwann cells (SCDEs) in protecting against mitochondrial dysfunction. This evaluation was conducted using a rat model of compressed SCI and in vitro experiments involving rat pheochromocytoma cells (PC12) exposed to oxygen-glucose deprivation (OGD). The conducted experiments yielded evidence that SCDEs effectively mitigated oxidative stress (OS) and inflammation subsequent to SCI, while concurrently diminishing necroptosis. Subsequent in vitro inquiry assessed the impact of SCDEs on PC12, with a specific emphasis on mitochondrial functionality, necrotic cell prevalence, and mitophagy. The study findings revealed that SCDEs enhanced mitophagy in PC12 cells, leading to a decrease in the generation of reactive oxygen species (ROS) and inflammatory cytokines (CK) provoked by OGD-induced injury. This, in turn, mitigated mitochondrial dysfunction and necroptosis. Mechanistically, SCDEs facilitated cellular mitophagy through activation of the AMPK signaling pathway. In conclusion, our data strongly support the notion that SCDEs hold considerable promise as a therapeutic approach for managing SCI. Furthermore, our investigation serves to elucidate the pivotal role of AMPK-mediated mitophagy in reducing cell damage, thereby unveiling novel prospects for enhancing neuro-pathological outcomes following SCI.


Assuntos
Exossomos , Traumatismos da Medula Espinal , Ratos , Animais , Mitofagia , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Exossomos/metabolismo , Necroptose , Transdução de Sinais , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/metabolismo , Mitocôndrias/metabolismo , Oxigênio/metabolismo , Células de Schwann/metabolismo , Células de Schwann/patologia
13.
ACS Appl Mater Interfaces ; 15(33): 39384-39395, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37555537

RESUMO

Efficient electrocatalysts and catalytic mechanisms remain a pressing need in Li-S electrochemistry to address lithium polysulfide (LiPS) shuttling and enhance conversion kinetics. This study presents the development of multifunctional VO2@rGO heterostructures, incorporating interfacial built-in electric field (BIEF) enhancement, as a Mott-Schottky electrocatalyst for Li-S batteries. Electrochemical experiments and theoretical analysis demonstrate that the interfacial BIEF between VO2 and rGO induces self-driven charge redistribution, resulting in accelerated charge transport rates, enhanced LiPS chemisorption, reduced energy barriers for Li2S nucleation/decomposition, and improved Li-ion diffusion behavior. The Mott-Schottky electrocatalyst, combining the strengths of VO2's anchoring ability, rGO's metallic conductivity, and BIEF's optimized charge transport, exhibits an outstanding "trapping-conversion" effect. The modified Li-S battery with a VO2@rGO-modified separator achieves a highly reversible capacity of 558.0 mAh g-1 at 2 C over 600 cycles, with an average decay rate of 0.048% per cycle. This research offers valuable insights into the design of Mott-Schottky electrocatalysts and their catalytic mechanisms, advancing high-efficiency Li-S batteries and other multielectron energy storage and conversion devices.

14.
J Orthop Surg Res ; 18(1): 410, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37277880

RESUMO

BACKGROUND: This study aimed to accurately evaluate the matching of proximal and distal femoral segments and fitting of the femur-femoral stem in patients with Crowe type IV developmental dysplasia of the hip (DDH) who have undergone subtrochanteric osteotomy at different locations with an implanted Wagner cone stem to improve the rate of the bone union at the osteotomy site. METHODS: Three-dimensional femur morphology of 40 patients with Crowe type IV DDH was evaluated at each cross-section to determine the femoral cortical bone area. This study focused on five osteotomy lengths (2.5, 3, 3.5, 4, and 4.5 cm). The overlapped area between the proximal and distal cortical bone segments was defined as the contact area (S, mm2), and the contact area to distal cortical bone area ratio was defined as the coincidence rate (R). Three indicators were used to evaluate the matching and fitting of the osteotomy sites with the implanted Wagner cone stems: (1) higher S and R between the proximal and distal segments; (2) the effective fixation length of the femoral stem at the distal segments being at least 1.5 cm; and (3) osteotomy did not involve the isthmus. RESULTS: In all groups, S significantly decreased in the two proximal levels above the 0.5 cm level below the lesser trochanter (LT) compared with those below this level. In comparison, at osteotomy lengths from 2.5 to 4 cm, R significantly decreased in the three proximal levels. The optimal osteotomy levels ranged from 1.5 and 2.5 cm below the LT for an appropriately sized stem. CONCLUSIONS: Subtrochanteric osteotomy at the optimal level not only ensures fitting of the femur-femoral stem but also meets the requirements of a higher S and R to ensure adequate reduction and stabilization at the osteotomy site, which may contribute to the bone union. Although the optimal osteotomy level varies with the size of the femoral stem and the length of the subtrochanteric osteotomy, the optimal osteotomy levels for an appropriately sized Wagner cone femoral stem implantation range from 1.5 to 2.5 cm below the LT.


Assuntos
Artroplastia de Quadril , Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Sinostose , Humanos , Artroplastia de Quadril/métodos , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/cirurgia , Displasia do Desenvolvimento do Quadril/cirurgia , Estudos Retrospectivos , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Osteotomia/métodos , Sinostose/cirurgia
15.
Small ; 19(37): e2301085, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194979

RESUMO

Polysulfide shuttle effect and sluggish sulfur reaction kinetics severely impede the cycling stability and sulfur utilization of lithium-sulfur (Li-S) batteries. Modulating d-band electronic structures of molybdenum disulfide electrocatalysts via p/n doping is promising to boost polysulfide conversion and suppress polysulfide migration in lithium-sulfur batteries. Herein, p-type V-doped MoS2 (V-MoS2 ) and n-type Mn-doped MoS2 (Mn-MoS2 ) catalysts are well-designed. Experimental results and theoretical analyses reveal that both of them significantly increase the binding energy of polysulfides on the catalysts' surface and accelerate the sluggish conversion kinetics of sulfur species. Particularly, the p-type V-MoS2 catalyst exhibits a more obvious bidirectional catalytic effect. Electronic structure analysis further demonstrates that the superior anchoring and electrocatalytic activities are originated from the upward shift of the d-band center and the optimized electronic structure induced by duplex metal coupling. As a result, the Li-S batteries with V-MoS2 modified separator exhibit a high initial capacity of 1607.2 mAh g-1 at 0.2 C and excellent rate and cycling performance. Moreover, even at a high sulfur loading of 6.84 mg cm-2 , a favorable initial areal capacity of 8.98 mAh cm-2 is achieved at 0.1 C. This work may bring widespread attention to atomic engineering in catalyst design for high-performance Li-S batteries.

16.
PLoS One ; 18(4): e0282907, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37098014

RESUMO

To control COVID-19 pandemic, complete lockdown was initiated in 2020. We investigated the impact of lockdown on tertiary-level academic performance, by comparing educational outcomes amongst first-year students during second semester of their medical course prior to and during lockdown. Evidence: The demographics, including educational outcomes of the two groups were not significantly different during semester one (prior to the lockdown). The academic performance amongst women was better than men prior to lockdown. However, the scores were improved significantly for both sexes during lockdown in 2020, following the complete online teaching, compared to that in 2019, showing no significant difference between men and women in 2020, for English and Chinese History. There were significant different scores between men and women in lab-based Histology Practice in 2019 (in-person tuition) and 2020 (online digital tuition), although only a significant improvement in women was observed between 2019 and 2020. Implication: the forced change to online delivery of the second semester of the first-year medical program in 2020 due to the COVID-19 pandemic did not result in any decline in assessment outcomes in any of the subjects undertaken. We believe extensive online digital media should continue to be available to students in future.


Assuntos
COVID-19 , Masculino , Humanos , Feminino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Internet , Pandemias , Controle de Doenças Transmissíveis , Escolaridade
17.
Zootaxa ; 5256(4): 358-370, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-37045219

RESUMO

Three new species of the genus Brachyllus Brenske, 1896 are described from China including Brachyllus songhaitiani Zhao, Qi, Su & Liao, new species from Fujian and Jiangxi, B. dongzhiweii Zhao, new species from Xizang and B. tangzhaoyangi Zhao, new species from Guangxi. Brachyllus langeri Keith, 2008 is downgraded to a subspecies of B. rougeriei Keith, 2003 and reported from China for the first time. Newly collected material of B. deuveianus Keith, 2003 allows better definition of its variability. A distribution map for this genus is also presented.


Assuntos
Besouros , Animais , China
18.
Nanoscale Horiz ; 8(5): 695-704, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36942884

RESUMO

Neutral electrosynthesis of H2O2via the 2e- ORR is attractive for numerous applications, but the low activity and high cost of electrocatalysts have become important constraints. Therefore, the development of cheap and efficient electrocatalysts for the 2e- ORR is necessary. Herein, we report the embedding of transition metal single atoms (TM SAs) in g-C3N4 nanosheets (CNNS). The introduction of TM SAs increases the N-CN content and reduces the C-C/CC content in CNNS, which contributes to the increased selectivity of TM SA/CNNS for the 2e- ORR. TM SA is the main reason for the enhanced activity of the 2e- ORR. Based on the results obtained by replacing a series of TM SA, the Ni0.10 SA/CNNS with optimal N-CN content exhibited the best selectivity (∼98%) and highest yield of H2O2 (∼503 mmol gcat-1 h-1), which is ∼14.6 times higher than that of CNNS (∼34.4 mmol gcat-1 h-1). Other TM SA/CNNS also exhibited high activity and selectivity. This study demonstrates the ability of TM SA to modulate the selectivity and activity of CNNS, making it a promising candidate for the 2e- ORR and providing more reference ideas for the preparation of H2O2.

19.
Aging Cell ; 22(6): e13807, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36890785

RESUMO

Ferroptosis is an iron-dependent cell death that has been found to aggravate the progression of osteoarthritis (OA) and gut microbiota- OA axis refers to the bidirectional information network between the gut microbiota and OA, which may provide a new way to protect the OA. However, the role of gut microbiota-derived metabolites in ferroptosis-relative osteoarthritis remains unclear. The objective of this study was to analyze the protective effect of gut microbiota and its metabolite capsiate (CAT) on ferroptosis-relative osteoarthritis in vivo and in vitro experiments. From June 2021 to February 2022, 78 patients were evaluated retrospectively and divided into two groups: The health group (n = 39) and the OA group (n = 40). Iron and oxidative stress indicators were determined in peripheral blood samples. And then in vivo and in vitro experiments, a surgically destabilized medial meniscus (DMM) mice model was established and treated with CAT or Ferric Inhibitor-1 (Fer-1). Solute Carrier Family 2 Member 1 (SLC2A1) short hairpin RNA (shRNA) was utilized to inhibit SLC2A1 expression. Serum iron was increased significantly but total iron binding capacity was decreased significantly in OA patients than healthy people (p < 0.0001). The least absolute shrinkage and selection operator clinical prediction model suggested that serum iron, total iron binding capacity, transferrin, and superoxide dismutase were all independent predictors of OA (p < 0.001). Bioinformatics results suggested that SLC2A1, Metastasis-Associated Lung Adenocarcinoma Transcript 1 (MALAT1), and HIF-1α (Hypoxia Inducible Factor 1 Alpha)-related oxidative stress signaling pathways play an important role in iron homeostasis and OA. In addition, gut microbiota 16s RNA sequencing and untargeted metabolomics were used to find that gut microbiota metabolites CAT in mice with osteoarthritis were negatively correlated with Osteoarthritis Research Society International (OARSI) scores for chondrogenic degeneration (p = 0.0017). Moreover, CAT reduced ferroptosis-dependent osteoarthritis in vivo and in vitro. However, the protective effect of CAT against ferroptosis-dependent osteoarthritis could be eliminated by silencing SLC2A1. SLC2A1 was upregulated but reduced the SLC2A1 and HIF-1α levels in the DMM group. HIF-1α, MALAT1, and apoptosis levels were increased after SLC2A1 knockout in chondrocyte cells (p = 0.0017). Finally, downregulation of SLC2A1 expression by Adeno-associated Virus (AAV) -SLC2A1 shRNA improves osteoarthritis in vivo. Our findings indicated that CAT inhibited HIF-1a expression and reduced ferroptosis-relative osteoarthritis progression by activating SLC2A1.


Assuntos
Ferroptose , Microbioma Gastrointestinal , Osteoartrite do Joelho , RNA Longo não Codificante , Camundongos , Animais , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Modelos Estatísticos , RNA Longo não Codificante/metabolismo , Estudos Retrospectivos , Prognóstico , Condrócitos/metabolismo , RNA Interferente Pequeno/metabolismo
20.
Sci Total Environ ; 857(Pt 3): 159651, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36280085

RESUMO

Rapid anthropogenic nutrient enrichment has caused widespread ecological problems in aquatic ecosystems and the resulting eutrophication has dramatically changed fish communities throughout the world. However, few studies addressed how fish communities responded to eutrophication in terms of multidimensional functional and taxonomic structure, especially how eutrophication acted as an environment filter on functional traits. The aim of the present study was to investigate the effects of eutrophication on fish species composition, community metrics and species functional traits in 26 shallow lakes from the middle reaches of Yangtze River basin, China. This study validated that eutrophication is an important factor shaping the fish community structure. Regression analyses showed that eutrophication favored higher total biomass and lower functional diversity of fish communities but had little effect on species richness. Despite the fact that some pelagic zooplanktivorous species were more abundant in the most eutrophic lakes, multivariate analyses of the relationships between species traits and environmental variables revealed weak relationships between feeding traits and eutrophication. In contrast, species with a benthic life stage were negatively associated with eutrophication while those with a large body size and high absolute fecundity showed the opposite trend. Due to demersal habitat degradation, and to a lesser degree, to changes in trophic resources availability, eutrophication caused functional simplification of fish communities by increasing functional traits homogeneity among the most tolerant species. Some relationships between functional traits and eutrophication well established in the western palearctic have not been observed in this study, emphasizing the importance of biases resulting from specific evolutionary histories. This work will provide useful insights on on-going restoration and management of shallow lakes in the Yangtze River basin.


Assuntos
Ecossistema , Eutrofização , Animais , Lagos , Peixes , Rios/química , China
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