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1.
Proc Natl Acad Sci U S A ; 120(20): e2214942120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155842

RESUMO

Aberrant accumulation of succinate has been detected in many cancers. However, the cellular function and regulation of succinate in cancer progression is not completely understood. Using stable isotope-resolved metabolomics analysis, we showed that the epithelial mesenchymal transition (EMT) was associated with profound changes in metabolites, including elevation of cytoplasmic succinate levels. The treatment with cell-permeable succinate induced mesenchymal phenotypes in mammary epithelial cells and enhanced cancer cell stemness. Chromatin immunoprecipitation and sequence analysis showed that elevated cytoplasmic succinate levels were sufficient to reduce global 5-hydroxymethylcytosinene (5hmC) accumulation and induce transcriptional repression of EMT-related genes. We showed that expression of procollagen-lysine,2-oxoglutarate 5-dioxygenase 2 (PLOD2) was associated with elevation of cytoplasmic succinate during the EMT process. Silencing of PLOD2 expression in breast cancer cells reduced succinate levels and inhibited cancer cell mesenchymal phenotypes and stemness, which was accompanied by elevated 5hmC levels in chromatin. Importantly, exogenous succinate rescued cancer cell stemness and 5hmC levels in PLOD2-silenced cells, suggesting that PLOD2 promotes cancer progression at least partially through succinate. These results reveal the previously unidentified function of succinate in enhancing cancer cell plasticity and stemness.


Assuntos
Neoplasias , Ácido Succínico , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Succinatos , Humanos
2.
Drug Resist Updat ; 76: 101111, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38908233

RESUMO

Gemcitabine (GEM) based induction chemotherapy is a standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). However, approximately 15 % of patients are still resistant to GEM-containing chemotherapy, which leads to treatment failure. Nevertheless, the underlying mechanisms of GEM resistance remain poorly understood. Herein, based on a microarray analysis, we identified 221 dysregulated lncRNAs, of which, DYNLRB2-AS1 was one of the most upregulated lncRNAs in GEM-resistance NPC cell lines. DYNLRB2-AS1 was shown to function as contain an oncogenic lncRNA that promoted NPC GEM resistance, cell proliferation, but inhibited cell apoptosis. Mechanistically, DYNLRB2-AS1 could directly bind to the DHX9 protein and prevent its interaction with the E3 ubiquitin ligase PRPF19, and thus blocking PRPF19-mediated DHX9 degradation, which ultimately facilitated the repair of DNA damage in the presence of GEM. Clinically, higher DYNLRB2-AS1 expression indicated an unfavourable overall survival of NPC patients who received induction chemotherapy. Overall, this study identified the oncogenic lncRNA DYNLRB2-AS1 as an independent prognostic biomarker for patients with locally advanced NPC and as a potential therapeutic target for overcoming GEM chemoresistance in NPC.


Assuntos
RNA Helicases DEAD-box , Desoxicitidina , Gencitabina , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , RNA Longo não Codificante , Animais , Humanos , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ubiquitinação/efeitos dos fármacos
3.
J Am Chem Soc ; 146(11): 7605-7615, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38467427

RESUMO

Cu-SSZ-13 has been commercialized for selective catalytic reduction with ammonia (NH3-SCR) to remove NOx from diesel exhaust. As its synthesis usually requires toxic and costly organic templates, the discovery of alternative Cu-based zeolite catalysts with organotemplate-free synthesis and comparable or even superior NH3-SCR activity to that of Cu-SSZ-13 is of great academic and industrial significance. Herein, we demonstrated that Cu-T with an intergrowth structure of offretite (OFF) and erionite (ERI) synthesized by an organotemplate-free method showed better catalytic performance than Cu-ERI and Cu-OFF as well as Cu-SSZ-13. Structure characterizations and density functional theory calculations indicated that the intergrowth structure promoted more isolated Cu2+ located at the 6MR of the intergrowth interface, resulting in a better hydrothermal stability of Cu-T than Cu-ERI and Cu-OFF. Strikingly, the low-temperature activity of Cu-T significantly increased after hydrothermal aging, while that of Cu-ERI and Cu-OFF substantially decreased. Based on in situ diffuse reflectance infrared Fourier transform spectra analysis and density functional theory calculations, the reason can be attributed to the fact that NH4NO3 formed on the CuxOy species within ERI polymorph of Cu-T underwent a fast SCR reaction pathway with the assistance of Brønsted acid sites at the intergrowth interfaces under standard SCR reaction conditions. Significantly, Cu-T exhibited a wider temperature window at a catalytic activity of over 90% than Cu-SSZ-13 (175-550 vs 175-500 °C for fresh and 225-500 vs 250-400 °C for hydrothermal treatment). This work provides a new direction for the design of high-performance NH3-SCR catalysts in terms of the interplay of the intergrowth structure of zeolites.

4.
J Am Chem Soc ; 146(35): 24358-24367, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39167721

RESUMO

Crystalline zeolites have been proven to be excellent supports for confining subnanometric metal catalysts to boost the propane dehydrogenation (PDH) reaction. However, the introduced metallic species may suffer from severe sintering and limited stability during the catalytic process, especially when utilizing an industrial impregnation method for metal incorporation. In this study, we developed a new type of support based on amorphous protozeolite (PZ), taking advantage of its adjustable silanol chemistry and zeolitic microporous characteristic for stabilizing atomically dispersed PtSn catalyst via a simple, cost-effective coimpregnation process. The combination of X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, in situ diffuse reflectance infrared Fourier transform spectroscopy under CO atmosphere, and density functional theory calculations confirmed the formation of highly dispersed active Ptδ+-Ox-Sn species in PtSn/PZ. The PtSn/PZ catalyst exhibited a high propane conversion of 45.4% and a high propylene selectivity of 99% (WHSV= 3.6 h-1, 550 °C), with a high apparent rate coefficient of 565 molC3H6·gPt-1·h-1·bar-1 at a high WHSV of 108 h-1, presenting a top-level performance among the state-of-the-art Pt-based catalysts prepared by in situ synthesis and impregnation methods. The silanol density determined the chemical state of PtSn species, showing a change from atomically dispersed Ptδ+-Ox-Sn sites to PtSn alloy with decreasing silanol density of supports. This work provides a general strategy using silanol-rich amorphous protozeolite as support for stabilizing various metal catalysts by the simple impregnation method and also offers an effective way for fine tailoring the chemical state of metallic species via a silanol-engineered approach.

5.
Plant Cell Environ ; 47(5): 1575-1591, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38269615

RESUMO

The spike growth phase is critical for the establishment of fertile floret (grain) numbers in wheat (Triticum aestivum L.). Then, how to shorten the spike growth phase and increase grain number synergistically? Here, we showed high-resolution analyses of floret primordia (FP) number, morphology and spike transcriptomes during the spike growth phase under three light regimens. The development of all FP in a spike could be divided into four distinct stages: differentiation (Stage I), differentiation and morphology development concurrently (Stage II), morphology development (Stage III), and polarization (Stage IV). Compared to the short photoperiod, the long photoperiod shortened spike growth and stimulated early flowering by shortening Stage III; however, this reduced assimilate accumulation, resulting in fertile floret loss. Interestingly, long photoperiod supplemented with red light shortened the time required to complete Stages I-II, then raised assimilates supply in the spike and promoted anther development before polarization initiation, thereby increasing fertile FP number during Stage III, and finally maintained fertile FP development during Stage IV until they became fertile florets via a predicted dynamic gene network. Our findings proposed a light regimen, critical stages and candidate regulators that achieved a shorter spike growth phase and a higher fertile floret number in wheat.


Assuntos
Flores , Triticum , Flores/fisiologia , Triticum/fisiologia , Perfilação da Expressão Gênica , Grão Comestível/genética , Fertilidade , Transcriptoma/genética
6.
Bioorg Chem ; 144: 107149, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38278048

RESUMO

The combination of steroid structure and selenocyano group offers high potential for the design and synthesis of new potential anti-tumor drugs. Beginning with estradiol, a series of 2-selenocyano-3-selenocyanoalkyloxyestradiol derivatives with remarkable antiproliferative activity was synthesized. Additionally, a 2,4-bisselenocyanoestradiol was synthesized by directly selenocyanating estradiol diacetate. It was found that the cytotoxicity of 2-selenocyano-3-selenocyanoalkyloxyestradiol derivatives was significantly increased in comparison to the corresponding monoselenocyanate precursor, whereas the cytotoxicity of the 2, 4-bisselenocyanoestradiol derivative was significantly reduced compared to the respective monosubstituted precursor. The introduction of the second selenocyano group at different locations of estradiol shows a various impact on the cytotoxicity of the compounds. Among them, compound 3e showed the best cytotoxicity, with an IC50 value of less than 5 µM against the tested tumor cells, and strong inhibitory activities against HeLa and MCF-7 cell xenograft tumors in zebrafish, suppressing tumor cell migration and neovascularization. Notably, compound 3e was more effective at inhibiting neovascularization of MCF-7 cell xenograft tumors than the positive control 2-methoxyestradiol. Furthermore, compound 3e showed excellent anti-oxidative stress effect in zebrafish. Therefore, these estrogen bisselenocyanate compounds may be promising anti-tumor agents, warranting further investigation.


Assuntos
Antineoplásicos , Peixe-Zebra , Animais , Humanos , Relação Estrutura-Atividade , Células MCF-7 , Antineoplásicos/química , Estradiol/farmacologia , Estrogênios , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Linhagem Celular Tumoral
7.
Acta Pharmacol Sin ; 45(10): 2186-2198, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38858494

RESUMO

T cell engaging bispecific antibodies (TCBs) have recently become significant in cancer treatment. In this study we developed MSLN490, a novel TCB designed to target mesothelin (MSLN), a glycosylphosphatidylinositol (GPI)-linked glycoprotein highly expressed in various cancers, and evaluated its efficacy against solid tumors. CDR walking and phage display techniques were used to improve affinity of the parental antibody M912, resulting in a pool of antibodies with different affinities to MSLN. From this pool, various bispecific antibodies (BsAbs) were assembled. Notably, MSLN490 with its IgG-[L]-scFv structure displayed remarkable anti-tumor activity against MSLN-expressing tumors (EC50: 0.16 pM in HT-29-hMSLN cells). Furthermore, MSLN490 remained effective even in the presence of non-membrane-anchored MSLN (soluble MSLN). Moreover, the anti-tumor activity of MSLN490 was enhanced when combined with either Atezolizumab or TAA × CD28 BsAbs. Notably, a synergistic effect was observed between MSLN490 and paclitaxel, as paclitaxel disrupted the immunosuppressive microenvironment within solid tumors, enhancing immune cells infiltration and improved anti-tumor efficacy. Overall, MSLN490 exhibits robust anti-tumor activity, resilience to soluble MSLN interference, and enhanced anti-tumor effects when combined with other therapies, offering a promising future for the treatment of a variety of solid tumors. This study provides a strong foundation for further exploration of MSLN490's clinical potential.


Assuntos
Proteínas Ligadas por GPI , Mesotelina , Humanos , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/antagonistas & inibidores , Animais , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Biespecíficos/farmacologia , Paclitaxel/uso terapêutico , Paclitaxel/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/terapia , Camundongos , Feminino , Células HT29 , Camundongos Endogâmicos BALB C , Camundongos Nus , Linhagem Celular Tumoral , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia
8.
World J Surg Oncol ; 22(1): 250, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285422

RESUMO

BACKGROUND: To investigate the prognostic differences following the achievement of a pathological complete response (pCR) through neoadjuvant chemotherapy across different molecular subtypes of breast invasive ductal carcinoma. METHODS: Data from the Surveillance, Epidemiology, and End Results (SEER) were identified for patients undergoing neoadjuvant chemotherapy who achieved pathological complete response for invasive ductal carcinoma of the breast between 2010 and 2019.Comparing the clinicopathological characteristics of patients across different molecular subtypes. Univariate and Cox multivariate analyses were utilized to identify independent predictors of overall survival (OS) and cancer-specific survival (CSS). The Kaplan-Meier method is used to compare OS and CSS among different molecular subtypes. After propensity score matching, subgroup analysis results were presented through forest plots. RESULTS: This study included 9,380 patients diagnosed with invasive ductal carcinoma, who were categorized into four molecular subtypes: 2,721 (29.01%) HR + /HER-2 + , 1,661 (17.71%) HR + /HER2-, 2,082 (22.20%) HR-/HER2 + , and 2,916 (31.08%) HR-/HER-2-. HR + /HER-2- subgroup exhibited a significantly higher proportion of patients under 50 years old than the other subtype groups (54.67% vs 40.2%, 50.35% and 51.82%, p < 0.01), and had a higher N2 + N3 stage (11.2% vs 7.24%, 8.69% and 7.48%, p < 0.01). Univariate and multivariate analysis revealed that molecular subtype was the independent risk factor for OS and CSS in patients(p < 0.05). The Kaplan-Meier curves indicated that the HR + /HER-2 + subtype had the highest OS and CSS(p < 0.05). Next, were the HR-/HER-2 + and HR-/HER-2- subtypes, with the HR + /HER-2- group having the lowest OS and CSS(p < 0.05). After propensity score matching, the OS and CSS of patients in the HR + /HER-2 + group remained higher compared to HR + /HER-2- group(p < 0.05). CONCLUSIONS: Patients with invasive ductal carcinoma of different molecular subtypes exhibit varying prognoses after achieving pCR to neoadjuvant chemotherapy. Those in the HR + /HER-2- group are younger, have a higher lymph node stage, and the lowest OS and CSS, whereas patients in the HR + /HER-2 + group have the highest OS and CSS.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Terapia Neoadjuvante , Receptor ErbB-2 , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Terapia Neoadjuvante/métodos , Terapia Neoadjuvante/mortalidade , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/metabolismo , Pessoa de Meia-Idade , Taxa de Sobrevida , Prognóstico , Receptor ErbB-2/metabolismo , Seguimentos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Adulto , Receptores de Progesterona/metabolismo , Programa de SEER , Receptores de Estrogênio/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/análise , Quimioterapia Adjuvante/métodos , Estudos Retrospectivos
9.
Plant Dis ; 108(4): 996-1004, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613135

RESUMO

Bacterial wilt caused by Ralstonia solanacearum (RS) is one of the most devastating diseases in patchouli (Pogostemon cablin [Blanco] Benth.), which results in low yield and quality of patchouli. However, no stable and effective control methods have been developed yet. To evaluate the potential of dominant bacterial endophytes in biocontrol, the endophytic bacterial diversity of patchouli was investigated based on Illumina sequencing analysis, and the ability of isolates belonging to the dominant bacterial genera to control RS wilt of patchouli was explored in pot experiments. A total of 245 bacterial genera were detected in patchouli plants, with the highest relative abundance of operational taxonomic units belonging to the genus Pseudomonas detected in roots, leaves, and stems. The Pseudomonas isolates S02, S09, and S26 showed antagonistic activity against RS in vitro and displayed many plant growth-promoting characteristics, including production of indole-3-acetic acid, siderophores, and 1-aminocyclopropane-1-carboxylic acid deaminase and phosphate- and potassium-solubilizing capability. Inoculation of patchouli plants with the isolates S02, S09, and S26 significantly improved shoot growth and decreased the incidence of bacterial wilt caused by RS. The results suggest that screening of dominant bacterial endophytes for effective biocontrol agents based on Illumina sequencing analysis is more efficient than random isolation and screening procedures.


Assuntos
Endófitos , Doenças das Plantas , Ralstonia solanacearum , Ralstonia solanacearum/fisiologia , Ralstonia solanacearum/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Endófitos/genética , Endófitos/fisiologia , Endófitos/isolamento & purificação , Pseudomonas/genética , Pseudomonas/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Agentes de Controle Biológico
10.
J Adv Nurs ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373552

RESUMO

AIM: To explore the lived experience of donors and recipients involved in peer-to-peer human milk donation. DESIGN: An exploratory descriptive qualitative study. METHOD: Semi-structured interviews were conducted between November 2022 and April 2023. A total of 50 women consisting of 34 donors and 16 recipients were recruited using purposive sampling from specific social media groups in Hong Kong that focus on breast milk donation and sharing. Data were analysed based on thematic analysis. RESULTS: Five key themes were identified in this study: Motivation; Milk sharing as a social act; Not a Norm; Recommendation to formal milk banks; and Formal donation as the preferred route. CONCLUSION: The findings indicate informal milk sharing is seen as an inferior alternative to formal milk donation systems. The establishment of formal milk banks is viewed as a way to address the shortcomings of informal sharing. IMPLICATIONS FOR THE PROFESSION: The findings have implications for the healthcare field, particularly in improving the experiences of those involved in informal milk sharing. The insights gained from the experiences of informal milk sharers can directly inform and enhance the services provided by formal milk banks. IMPACT: Given the growing prevalence of online informal milk sharing, healthcare professionals should enhance their understanding of this practice. However, the practice has remained understudied, particularly in Asian region. This study brings together the experiences of both milk donors and recipients, providing a comprehensive view on the phenomenon. REPORTING METHOD: The Standards for Reporting Qualitative Research (SRQR). PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

11.
Int Orthop ; 48(10): 2567-2577, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39212693

RESUMO

PURPOSE: This study aims to assess the impact of repairing the hip joint capsule during posterior-lateral approach total hip arthroplasty (THA) on postoperative hip joint function and late dislocation incidence. METHODS: A retrospective cohort study included 413 patients, divided into experimental (hip joint capsule repair, n = 204) and control (hip joint capsule excision, n = 209) groups. Patients were followed for five years, evaluating postoperative hip range of motion (ROM), dislocation rate, VAS and HHS scores, inflammatory and coagulation markers, hospitalization, blood loss, and body composition. Statistical analysis included the Student's t-test, Chi-square test, and logistic regression for dislocation risk factors. RESULTS: Joint capsule repair improved postoperative hip flexion and extension within six months and at two years postoperatively, internal and external rotation within three months, and abduction and adduction throughout the entire follow-up period (P < 0.05). Capsular repair also reduced early and late dislocation rates (P < 0.05). Significant differences in HHS and VAS scores, inflammatory and coagulation indicators, hospitalization, blood loss, and body composition were noted (P < 0.05). Multivariate logistic regression indicated hip joint repair, rheumatoid arthritis, epilepsy, and sarcopenia as dislocation risk factors (P < 0.05). CONCLUSIONS: Capsular repair during posterior-lateral THA improves postoperative hip function and mobility while reducing dislocation rates, blood loss, pain, inflammation, and economic burden. Patients with rheumatoid arthritis, epilepsy, or sarcopenia require individualized planning and enhanced postoperative care to minimize complications.


Assuntos
Artroplastia de Quadril , Articulação do Quadril , Cápsula Articular , Amplitude de Movimento Articular , Humanos , Artroplastia de Quadril/métodos , Artroplastia de Quadril/efeitos adversos , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular/fisiologia , Idoso , Cápsula Articular/cirurgia , Articulação do Quadril/cirurgia , Articulação do Quadril/fisiopatologia , Luxação do Quadril/prevenção & controle , Luxação do Quadril/etiologia , Luxação do Quadril/epidemiologia , Luxação do Quadril/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Adulto , Resultado do Tratamento , Fatores de Risco
12.
Angew Chem Int Ed Engl ; 63(15): e202319996, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38316641

RESUMO

Metal halide perovskites (MHPs), renowned for their outstanding optoelectronic properties, hold significant promise as photocatalysts for hydrogen evolution reaction (HER). However, the low stability and insufficient exposure of catalytically active sites of bulky MHPs seriously impair their catalytic efficiency. Herein, we utilized an extra-large-pore zeolite ZEO-1 (JZO) as a host to confine and stabilize the CsPbBr3 nanocrystals (3.4 nm) for boosting hydrogen iodide (HI) splitting. The as-prepared CsPbBr3@ZEO-1 featured sufficiently exposed active sites, superior stability in acidic media, along with intrinsic extra-large pores of ZEO-1 that were favorable for molecule/ion adsorption and diffusion. Most importantly, the unique nanoconfinement effect of ZEO-1 led to the narrowing of the band gap of CsPbBr3, allowing for more efficient light utilization. As a result, the photocatalytic HER rate of the as-prepared CsPbBr3@ZEO-1 photocatalyst was increased to 1734 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3) under visible light irradiation compared with bulk CsPbBr3 (11 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3)), and the long-term durability (36 h) can be achieved. Furthermore, Pt was incorporated with well-dispersed CsPbBr3 nanocrystals into ZEO-1, resulting in a significant enhancement in activity (4826 µmol ⋅ h-1 ⋅ g-1 (CsPbBr3)), surpassing most of the Pt-integrated perovskite-based photocatalysts. Density functional theory (DFT) calculations and charge-carrier dynamics investigation revealed that the dramatically boosted photocatalytic performance of Pt/CsPbBr3@ZEO-1 could be attributed to the promotion of charge separation and transfer, as well as to the substantially lowered energy barrier for HER. This work highlights the advantage of extra-large-pore zeolites as the nanoscale platform to accommodate multiple photoactive components, opening up promising prospects in the design and exploitation of novel zeolite-confined photocatalysts for energy harvesting and storage.

13.
Angew Chem Int Ed Engl ; 63(44): e202410017, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39072969

RESUMO

As a fundamental industrial catalytic process, the semihydrogenation of alkynes presents a challenge in striking a balance between activity and selectivity due to the issue of over-hydrogenation. Herein, we develop an efficient catalytic system based on single-atom Pd catalysts supported on boron-containing amorphous zeolites (Pd/AZ-B), achieving the tradeoff breaking between the activity and selectivity for the selective hydrogenation of alkynes. Advanced characterizations and theoretical density functional theory calculations confirm that the incorporated B atoms in the Pd/AZ-B can not only alter the geometric and electronic properties of Pd atoms by controlling the electron migration from Pd but also mitigate the interaction between alkene and the catalyst supports. This boosts the exceptional catalytic efficacy in the semihydrogenation of phenylacetylene to styrene under mild conditions (298 K, 2 bar H2), achieving a recorded turnover frequency (TOF) value of 24198 h-1 and demonstrating 95 % selectivity to styrene at full conversion of phenylacetylene. By comparison, the heteroatom-free amorphous zeolite-anchored Pd nanoparticles and the commercial Lindlar catalyst have styrene selectivities of 73 % and 15 %, respectively, under identical reaction conditions. This work establishes a solid foundation for developing highly active and selective hydrogenation catalysts by controllably optimizing their electronic and steric properties.

14.
J Am Chem Soc ; 145(39): 21231-21241, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37748094

RESUMO

Zeolite nonclassical growth via particle attachment has been proposed for two decades, yet the attachment mechanism and kinetic regulation remain elusive. Here, nonclassical growth of an MFI-type zeolite has been achieved by using amorphous protozeolite (PZ) nanoparticles containing encapsulated TPA+ templates and abundant silanols (Si-OH) as sole precursors under hydrothermal conditions. The silanol characteristics of the precursor were studied by two-dimensional (2D) solid-state nuclear magnetic resonance (NMR) correlation spectroscopy, which were proven to play critical roles in determining precursor attachment behavior and crystal growth orientation. Under mechanical ball-milling or tablet-pressing process, pressure drove the fusion of spherical PZ into platelet-like integrated PZ (IPZ) coupled with transformations of external silanols from evenly distributed to curvature-dependent distributed and internal silanols from isolated to spatially proximate. Compared to isolated silanols, the spatially proximate silanols possessed a stronger correlation with TPA+, benefiting the formation of Si-O-Si bonds via silanol condensation. Subsequently, driven by minimization of surface energy, particle attachment of the platelet-like IPZ precursor preferentially occurred at high-curvature surfaces with high-density silanols, leading to anisotropic rates of nonclassical growth and thus the formation of high-aspect-ratio MFI-type zeolite nanosheets. Advanced electron microscopy provided direct evidence of attachment of amorphous IPZ precursors to crystalline intermediate surfaces along the c-axis direction with the formation of amorphous-crystalline interfaces, followed by interface elimination and structural evolution to a single-crystalline phase. Our findings not only unravel the zeolite nonclassical growth mechanism but also reveal the critical role of silanol chemistry in kinetic regulation, which is of great importance for pursuing a tailored zeolite synthesis.

15.
J Am Chem Soc ; 145(50): 27740-27747, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38059924

RESUMO

Mass adoption of electric vehicles and the depletion of finite metal resources make it imperative to recycle lithium-ion batteries (LIBs). However, current recycling routes of pyrometallurgy and hydrometallurgy are mainly developed for LiCoO2 and suffer from great energy inputs and extensive processing; thus, alternative versatile and green approaches are in urgent demand. Here, we report an ingenious and versatile strategy for recycling LIBs via catalyst reconstruction, using hydrogen evolution reaction as a proof of concept. Layered, spinel, and polyanion oxide cathode materials, as catalysts, are structurally transformed into hydroxides assisted by protons or hydroxide ions, facilitating complete metal extraction (e.g., Li, Co, Ni, Mn, Fe) with high leaching efficiencies approaching 100%. This recycling method is generally applicable to almost all commercial cathode systems and extended to actual spent pouch cells. Such a green hydrogen coupling approach provides a versatile and sustainable alternative to conventional approaches and has a broad impact beyond battery recycling.

16.
Cancer Sci ; 114(6): 2429-2444, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36928924

RESUMO

Transforming growth factor-ß (TGF-ß) is known to promote breast cancer cell migration, invasion, and dissemination; however, the underlying molecular mechanisms are not yet well characterized. Here, we report that TGF-ß induces pleckstrin-2 (PLEK2) expression by Smad3 and signal transducer and activator of transcription 3 (STAT3) activating PLEK2 promoter activity. Higher PLEK2 expression is associated with poor prognosis in breast cancer patients. Overexpression and knockout experiments in MDA-MB-231 and MCF-7 breast cancer cells revealed that PLEK2 promotes cell migration, invasion, and dissemination in 2D and 3D cell culture. Moreover, PLEK2 promotes metastasis of breast cancer cells in vivo. Pleckstrin-2 localizes to the cell membrane and cell protrusions following TGF-ß treatment. Furthermore, inhibition of PI3K phosphorylation abolishes TGF-ß- and PLEK2-induced cell invasion. The carboxyl-terminal PH domain of PLEK2 is critical for TGF-ß- and PLEK2-induced Akt activation and plays an important role in cell invasion. Pleckstrin-2 interacts with PPM1B and promotes its ubiquitin-dependent degradation. The PLEK2-PPM1B axis utilizes nuclear factor-κB signaling to promote cell migration and invasion. Our data implicate the TGF-ß-STAT3/Smad3-PLEK2-PPM1B signaling cascade in TGF-ß-induced breast cancer cell migration and invasion. These findings suggest that PLEK2/PPM1B could represent novel targets for the intervention of breast cancer metastasis.


Assuntos
Neoplasias da Mama , Fator de Crescimento Transformador beta , Feminino , Humanos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proteínas de Membrana/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Proteína Fosfatase 2C , Fator de Crescimento Transformador beta/metabolismo , Fatores de Crescimento Transformadores
17.
Chemistry ; 29(33): e202300614, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37013359

RESUMO

A precise investigation of NbO has been carried out by advanced electron microscopy combined with powder and single crystal X-ray diffraction (XRD). The structure of pristine NbO has been determined as Pm-3 m space group (SG) with a = 4.211 Šand the positions of Nb and O at the 3c and 3d Wyckoff positions, respectively, which is consistent with previous report based on powder XRD data. Electron beams induced a structural transition, which was investigated and explained by combining electron diffraction and atomic-resolution imaging. The results revealed that the electron beam stimulated both Nb and O atom-migrations within each fcc sublattice, and that the final structure was SG Fm-3 m with a = 4.29 Å, Nb and O at the 4a and 4b with 75 % occupancy and same chemical composition. Antiphase planar defects were discovered in the pristine NbO and related to the structural transformation. Theoretical calculations performed by density functional theory (DFT) supported the experimental conclusions.


Assuntos
Elétrons , Nióbio , Nióbio/química , Pós , Cristalografia por Raios X , Microscopia Eletrônica
18.
Neurochem Res ; 48(1): 238-249, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36063295

RESUMO

Lead (Pb) is considered to be a major environmental pollutant and occupational health hazard worldwide which may lead to neuroinflammation. However, an effective treatment for Pb-induced neuroinflammation remains elusive. The aim of this study was to investigate the mechanisms of Pb-induced neuroinflammation, and the therapeutic effect of sodium para-aminosalicylic acid (PAS-Na, a non-steroidal anti-inflammatory drug) in rat cerebral cortex. The results indicated that Pb exposure induced pathological damage in cerebral cortex, accompanied by increased levels of inflammatory factors tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß). Moreover, Pb decreased the expression of silencing information regulator 2 related enzyme 1 (SIRT1) and brain-derived neurotrophic factor (BDNF), and increased the levels of high mobile group box 1 (HMGB1) expression and p65 nuclear factor-κB (NF-κB) phosphorylation. PAS-Na treatment ameliorated Pb-induced histopathological changes in rat cerebral cortex. Moreover, PAS-Na reduced the Pb-induced increase of TNF-α and IL-1ß levels concomitant with a significant increase in SIRT1 and BDNF levels, and a decrease in HMGB1 and the phosphorylation of p65 NF-κB expression. Thus, PAS-Na may exert anti-inflammatory effects by mediating the SIRT1/HMGB1/NF-κB pathway and BDNF expression. In conclusion, in this novel study PAS-Na was shown to possess an anti-inflammatory effect on cortical neuroinflammation, establishing its efficacy as a potential treatment for Pb exposures.


Assuntos
Ácido Aminossalicílico , Proteína HMGB1 , Ratos , Animais , NF-kappa B/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína HMGB1/metabolismo , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo , Doenças Neuroinflamatórias , Sódio , Sirtuína 1/metabolismo , Chumbo/toxicidade , Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Anti-Inflamatórios
19.
Clin Chem Lab Med ; 61(12): 2229-2236, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-37441737

RESUMO

OBJECTIVES: To evaluate the consistency of 14 high-risk HPVs (hr-HPVs) detection between extended HPV DNA genotyping and a well-validated partial HPV genotyping kit, and to explore the diagnostic accuracy of risk stratification strategy based on extended HPV genotyping for cervical cancer (CC) screening. METHODS: Baseline data from a clinical trial of recombinant HPV 9-valent vaccine in China was analyzed. All enrolled women aged 20-45 years received cervical cytology, HPV detection by extended and partial HPV genotyping kits. Those who met the indications would further receive colposcopy. The primary endpoints were cervical intraepithelial neoplasia 2/3 or worse (CIN2+/CIN3+). RESULTS: A total of 8,000 women were enrolled between April 2020 and July 2020 and 83/33 cases were diagnosed as CIN2+/CIN3+. The overall agreement between the extended and partial HPV genotyping was 92.66 %. And the agreement further increased with the progression of lesions, which lead to similarly high sensitivity and negative predictive value of these kits. A stratified triage strategy of CC screening was constructed based on the immediate CIN2+/CIN3+ risk of specific HPV. Compared with the conventional HPV primary CC screening strategy, the risk-based strategy had higher specificity for CIN (CIN2+: 94.84 vs. 92.46 %, CIN3+: 96.05 vs. 91.92 %), and needed fewer colposcopies for detecting one cervical disease. CONCLUSIONS: Extended HPV genotyping had good agreement with a well-validated partial HPV genotyping CC primary screening kit in hr-HPV detection. Extended HPV genotyping could facilitate risk-based stratified management strategy and improve the diagnostic accuracy of primary CC screening.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , DNA Viral/genética , Detecção Precoce de Câncer , Genótipo , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico
20.
Environ Res ; 236(Pt 2): 116856, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37574102

RESUMO

Extraction and utilization of effective phosphorus from solid waste have been an important approach for alleviating phosphorus resource shortage. The extraction of available phosphorus by microbial method with low cost, mild conditions and simple process has been drawing attention from the majority of research scholars. However, relevant studies on special microbial communities for effective phosphorus extraction from solid waste are less. In this work,a functional Bacillus_cereus strain screened from phosphate tailings, phosphate ore and forest rhizosphere soil was inoculated into phosphate tailings (PT), modified phosphate tailings (IS) and highland red soil (SS). Compared with SS, the water-holding properties, fertility, leaching toxicity and microbial community diversity of PT and IS with and without bacteria were analyzed. PT+, SS+ and IS+ (after adding bacteria to PT, SS and IS) showed moderately alkaline pH, and the available phosphorus content enhanced by 31.73%, 20.05% and 39.41% respectively. The leaching toxicity phosphate of PT+ and IS + decreased by 4.89 mg/kg and 2.61 mg/kg respectively, while that of SS + increased by 5.45 mg/kg, indicating differences in the phosphorus solubilization mechanism of Bacillus_cereus for different soils. Furthermore, the modification and bacteria treatment improved the relative abundance of Pedobacter, Alcaligenaceae and Pseudomonas, thus enhancing the phosphorus solubility of the PT bacterial community. This work may achieve efficient utilization and ecological restoration of phosphorus tailings-based soil and contribute to long-term sustainable agricultural development.

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