Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 850
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nature ; 631(8020): 307-312, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38898280

RESUMO

Spin accumulation in semiconductor structures at room temperature and without magnetic fields is key to enable a broader range of optoelectronic functionality1. Current efforts are limited owing to inherent inefficiencies associated with spin injection across semiconductor interfaces2. Here we demonstrate spin injection across chiral halide perovskite/III-V interfaces achieving spin accumulation in a standard semiconductor III-V (AlxGa1-x)0.5In0.5P multiple quantum well light-emitting diode. The spin accumulation in the multiple quantum well is detected through emission of circularly polarized light with a degree of polarization of up to 15 ± 4%. The chiral perovskite/III-V interface was characterized with X-ray photoelectron spectroscopy, cross-sectional scanning Kelvin probe force microscopy and cross-sectional transmission electron microscopy imaging, showing a clean semiconductor/semiconductor interface at which the Fermi level can equilibrate. These findings demonstrate that chiral perovskite semiconductors can transform well-developed semiconductor platforms into ones that can also control spin.

2.
Nature ; 623(7986): 313-318, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37696288

RESUMO

Metal halide perovskite solar cells (PSCs) represent a promising low-cost thin-film photovoltaic technology, with unprecedented power conversion efficiencies obtained for both single-junction and tandem applications1-8. To push PSCs towards commercialization, it is critical, albeit challenging, to understand device reliability under real-world outdoor conditions where multiple stress factors (for example, light, heat and humidity) coexist, generating complicated degradation behaviours9-13. To quickly guide PSC development, it is necessary to identify accelerated indoor testing protocols that can correlate specific stressors with observed degradation modes in fielded devices. Here we use a state-of-the-art positive-intrinsic-negative (p-i-n) PSC stack (with power conversion efficiencies of up to approximately 25.5%) to show that indoor accelerated stability tests can predict our six-month outdoor ageing tests. Device degradation rates under illumination and at elevated temperatures are most instructive for understanding outdoor device reliability. We also find that the indium tin oxide/self-assembled monolayer-based hole transport layer/perovskite interface most strongly affects our device operation stability. Improving the ion-blocking properties of the self-assembled monolayer hole transport layer increases averaged device operational stability at 50 °C-85 °C by a factor of about 2.8, reaching over 1,000 h at 85 °C and to near 8,200 h at 50 °C, with a projected 20% degradation, which is among the best to date for high-efficiency p-i-n PSCs14-17.

3.
Nature ; 611(7935): 278-283, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36049505

RESUMO

Perovskite solar cells (PSCs) with an inverted structure (often referred to as the p-i-n architecture) are attractive for future commercialization owing to their easily scalable fabrication, reliable operation and compatibility with a wide range of perovskite-based tandem device architectures1,2. However, the power conversion efficiency (PCE) of p-i-n PSCs falls behind that of n-i-p (or normal) structure counterparts3-6. This large performance gap could undermine efforts to adopt p-i-n architectures, despite their other advantages. Given the remarkable advances in perovskite bulk materials optimization over the past decade, interface engineering has become the most important strategy to push PSC performance to its limit7,8. Here we report a reactive surface engineering approach based on a simple post-growth treatment of 3-(aminomethyl)pyridine (3-APy) on top of a perovskite thin film. First, the 3-APy molecule selectively reacts with surface formamidinium ions, reducing perovskite surface roughness and surface potential fluctuations associated with surface steps and terraces. Second, the reaction product on the perovskite surface decreases the formation energy of charged iodine vacancies, leading to effective n-type doping with a reduced work function in the surface region. With this reactive surface engineering, the resulting p-i-n PSCs obtained a PCE of over 25 per cent, along with retaining 87 per cent of the initial PCE after over 2,400 hours of 1-sun operation at about 55 degrees Celsius in air.

4.
EMBO J ; 41(6): e108016, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35191555

RESUMO

Interferon regulatory factor 3 (IRF3)-induced type I interferon (I-IFN) production plays key roles in both antiviral and autoimmune responses. IRF3 phosphorylation, dimerization, and nuclear localization are needed for its activation and function, but the precise regulatory mechanisms remain to be explored. Here, we show that the serine/threonine kinase AKT2 interacts with IRF3 and phosphorylates it on Thr207, thereby attenuating IRF3 nuclear translocation in a 14-3-3ε-dependent manner and reducing I-IFN production. We further find that AKT2 expression is downregulated in viral-infected macrophages or in monocytes and tissue samples from systemic lupus erythematosus (SLE) patients and mouse models. Akt2-deficient mice exhibit increased I-IFN induction and reduced mortality in response to viral infection, but aggravated severity of SLE. Overexpression of AKT2 kinase-inactive or IRF3-T207A mutants in zebrafish supports that AKT2 negatively regulates I-IFN production and antiviral response in a kinase-dependent manner. This negative role of AKT2 in IRF3-induced I-IFN production suggests that AKT2 may be therapeutically targeted to differentially regulate antiviral infection and SLE.


Assuntos
Interferon beta/biossíntese , Lúpus Eritematoso Sistêmico , Peixe-Zebra , Animais , Antivirais , Humanos , Lúpus Eritematoso Sistêmico/genética , Camundongos , Fosforilação , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Peixe-Zebra/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(42): e2213718119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215477

RESUMO

Transcription factors (TFs) play critical roles in hematopoiesis, and their aberrant expression can lead to various types of leukemia. The t(8;21) leukemogenic fusion protein AML1-ETO (AE) is the most common fusion protein in acute myeloid leukemia and can enhance hematopoietic stem cell renewal while blocking differentiation. A key question in understanding AE-mediated leukemia is what determines the choice of AE to activate self-renewal genes or repress differentiation genes. Toward the resolution of this problem, we earlier showed that AE resides in the stable AETFC complex and that its components colocalize on up- or down-regulated target genes and are essential for leukemogenesis. In the current study, using biochemical and genomic approaches, we show that AE-containing complexes are heterogeneous, and that assembly of the larger AETFC (containing AE, CBFß, HEB, E2A, LYL1, LMO2, and LDB1) requires LYL1. Furthermore, we provide strong evidence that the LYL1-containing AETFC preferentially binds to active enhancers and promotes AE-dependent gene activation. Moreover, we show that coactivator CARM1 interacts with AETFC and facilitates gene activation by AETFC. Collectively, this study describes a role of oncoprotein LYL1 in AETFC assembly and gene activation by recruiting CARM1 to chromatin for AML cell survival.


Assuntos
Leucemia Mieloide Aguda , Proteínas de Fusão Oncogênica , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas Adaptadoras de Sinalização CARD , Cromatina , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Guanilato Ciclase , Humanos , Proteínas com Homeodomínio LIM/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteína-Arginina N-Metiltransferases , Ativação Transcricional
6.
Oncologist ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842680

RESUMO

BACKGROUND: Patients with intrahepatic cholangiocarcinoma (ICC) are prone to recurrence and poor survival. Targeted therapy related to isocitrate dehydrogenase (IDH) is an extremely important treatment. IDH1 and IDH2 mutations are generally thought to have similar effects on the tumor landscape. However, it is doubtful whether these 2 mutations have exactly the same effects on tumor cells and the tumor microenvironment. METHODS: All collected tumor samples were subjected to simultaneous whole-exon sequencing and proteome sequencing. RESULTS: IDH1 mutations accounted for 12.2%, and IDH2 mutations accounted for 5.5%, all missense mutations. Tumors with IDH mutations had lower proportions of KRAS and TP53 mutations. Mutated genes were obviously enriched in the kinase pathway in the tumors with IDH2 mutations. The signaling pathways were mainly enriched in the activation of cellular metabolic activities and an increase of inhibitory immune cells in the tumors with IDH mutations. Moreover, tumors had unique enrichment in DNA repair in IDH1 mutants and secretion of biological molecules in IDH2 mutants. Inhibitory immune cells might be more prominent in IDH2 mutants, and the expression of immune checkpoints PVR and HLA-DQB1 was more prominent in IDH1 mutants. IDH mutants were more related to metabolism-related and inflammation-immune response clusters, and some belonged to the DNA replication and repair cluster. CONCLUSIONS: These results revealed the differential IDH1 and IDH2 mutation-related landscapes, and we have provided an important reference database to guide ICC treatment.

7.
Anal Chem ; 96(22): 9209-9217, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38769607

RESUMO

To tackle the predicament of the traditional turn-off mechanism, exploring an activated turn-on system remains an intriguing and crucial objective in biosensing fields. Herein, a dark DNA Ag nanocluster (NC) with hairpin-structured DNA containing a six-base cytosine loop (6C loop) as a template is atypically synthesized. Intriguingly, the dark DNA Ag NCs can be lit to display strong red-emission nanoclusters. Building upon these exciting findings, an unprecedented and upgraded turn-on biosensing system [entropy-driven catalysis circuit (EDCC)-Ag NCs/graphene oxide (GO)] has been created, which employs an EDCC to precisely manipulate the conformational transition of DNA Ag NCs on the GO surface from adsorption to desorption. Benefiting from the effective quenching of GO and signal amplification capability of the EDCC, the newly developed EDCC-Ag NCs/GO biosensing system displays a high signal-to-background (S/B) ratio (26-fold) and sensitivity (limit of detection as low as 0.4 pM). Meanwhile, it has good specificity, excellent stability, and reliability in both buffer and biological samples. To the best of our knowledge, it is the first example that adopts an EDCC to precisely modulate the configuration transformation of DNA Ag NCs on the GO surface to obtain a biosensor with low background, strong fluorescence, high contrast, and sensitivity. This exciting finding may provide a new route to fabricate a novel turn-on biosensor based on hairpin-templated DNA Ag NCs in the optical imaging and bioanalytical fields.


Assuntos
Técnicas Biossensoriais , DNA , Grafite , Nanopartículas Metálicas , Prata , Propriedades de Superfície , Grafite/química , Prata/química , Técnicas Biossensoriais/métodos , DNA/química , Nanopartículas Metálicas/química , Catálise , Entropia , Humanos
8.
Biol Reprod ; 110(3): 450-464, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38035769

RESUMO

Adenosylhomocysteinase (AHCY), a key enzyme in the methionine cycle, is essential for the development of embryos and the maintenance of mouse embryonic stem cells (mESCs). However, the precise underlying mechanism of Ahcy in regulating pluripotency remains unclear. As the only enzyme that can hydrolyze S-adenosylhomocysteine in mammals, AHCY plays a critical role in the metabolic homeostasis, epigenetic remodeling, and transcriptional regulation. Here, we identified Ahcy as a direct target of OCT4 and unveiled that AHCY regulates the self-renewal and differentiation potency of mESCs through multiple mechanisms. Our study demonstrated that AHCY is required for the metabolic homeostasis of mESCs. We revealed the dual role of Ahcy in both transcriptional activation and inhibition, which is accomplished via the maintenance of H3K4me3 and H3K27me3, respectively. We found that Ahcy is required for H3K4me3-dependent transcriptional activation in mESCs. We also demonstrated that AHCY interacts with polycomb repressive complex 2 (PRC2), thereby maintaining the pluripotency of mESCs by sustaining the H3K27me3-regulated transcriptional repression of related genes. These results reveal a previously unrecognized OCT4-AHCY-PRC2 axis in the regulation of mESCs' pluripotency and provide insights into the interplay between transcriptional factors, cellular metabolism, chromatin dynamics and pluripotency regulation.


Assuntos
Histonas , Células-Tronco Embrionárias Murinas , Animais , Camundongos , Adenosil-Homocisteinase/genética , Adenosil-Homocisteinase/metabolismo , Diferenciação Celular , Histonas/metabolismo , Mamíferos/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Complexo Repressor Polycomb 2/genética
9.
Plant Biotechnol J ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600703

RESUMO

Sterols have long been associated with diverse fields, such as cancer treatment, drug development, and plant growth; however, their underlying mechanisms and functions remain enigmatic. Here, we unveil a critical role played by a GmNF-YC9-mediated CCAAT-box transcription complex in modulating the steroid metabolism pathway within soybeans. Specifically, this complex directly activates squalene monooxygenase (GmSQE1), which is a rate-limiting enzyme in steroid synthesis. Our findings demonstrate that overexpression of either GmNF-YC9 or GmSQE1 significantly enhances soybean stress tolerance, while the inhibition of SQE weakens this tolerance. Field experiments conducted over two seasons further reveal increased yields per plant in both GmNF-YC9 and GmSQE1 overexpressing plants under drought stress conditions. This enhanced stress tolerance is attributed to the reduction of abiotic stress-induced cell oxidative damage. Transcriptome and metabolome analyses shed light on the upregulation of multiple sterol compounds, including fucosterol and soyasaponin II, in GmNF-YC9 and GmSQE1 overexpressing soybean plants under stress conditions. Intriguingly, the application of soybean steroids, including fucosterol and soyasaponin II, significantly improves drought tolerance in soybean, wheat, foxtail millet, and maize. These findings underscore the pivotal role of soybean steroids in countering oxidative stress in plants and offer a new research strategy for enhancing crop stress tolerance and quality from gene regulation to chemical intervention.

10.
J Virol ; 97(11): e0122623, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37861337

RESUMO

IMPORTANCE: Although a virus can regulate many cellular responses to facilitate its replication by interacting with host proteins, the host can also restrict virus infection through these interactions. In the present study, we showed that the host eukaryotic translation elongation factor 1 alpha (eEF1A), an essential protein in the translation machinery, interacted with two proteins of a fish rhabdovirus, Siniperca chuatsi rhabdovirus (SCRV), and inhibited virus infection via two different mechanisms: (i) inhibiting the formation of crucial viral protein complexes required for virus transcription and replication and (ii) promoting the ubiquitin-proteasome degradation of viral protein. We also revealed the functional regions of eEF1A that are involved in the two processes. Such a host protein inhibiting a rhabdovirus infection in two ways is rarely reported. These findings provided new information for the interactions between host and fish rhabdovirus.


Assuntos
Doenças dos Peixes , Proteínas de Peixes , Fator 1 de Elongação de Peptídeos , Infecções por Rhabdoviridae , Rhabdoviridae , Animais , Peixes , Fator 1 de Elongação de Peptídeos/genética , Fator 1 de Elongação de Peptídeos/metabolismo , Rhabdoviridae/fisiologia , Infecções por Rhabdoviridae/metabolismo , Infecções por Rhabdoviridae/veterinária , Proteínas Virais/genética , Proteínas Virais/metabolismo , Proteínas de Peixes/metabolismo , Doenças dos Peixes/metabolismo
11.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36259363

RESUMO

Robust strategies to identify patients at high risk for tumor metastasis, such as those frequently observed in intrahepatic cholangiocarcinoma (ICC), remain limited. While gene/protein expression profiling holds great potential as an approach to cancer diagnosis and prognosis, previously developed protocols using multiple diagnostic signatures for expression-based metastasis prediction have not been widely applied successfully because batch effects and different data types greatly decreased the predictive performance of gene/protein expression profile-based signatures in interlaboratory and data type dependent validation. To address this problem and assist in more precise diagnosis, we performed a genome-wide integrative proteome and transcriptome analysis and developed an ensemble machine learning-based integration algorithm for metastasis prediction (EMLI-Metastasis) and risk stratification (EMLI-Prognosis) in ICC. Based on massive proteome (216) and transcriptome (244) data sets, 132 feature (biomarker) genes were selected and used to train the EMLI-Metastasis algorithm. To accurately detect the metastasis of ICC patients, we developed a weighted ensemble machine learning method based on k-Top Scoring Pairs (k-TSP) method. This approach generates a metastasis classifier for each bootstrap aggregating training data set. Ten binary expression rank-based classifiers were generated for detection of metastasis separately. To further improve the accuracy of the method, the 10 binary metastasis classifiers were combined by weighted voting based on the score from the prediction results of each classifier. The prediction accuracy of the EMLI-Metastasis algorithm achieved 97.1% and 85.0% in proteome and transcriptome datasets, respectively. Among the 132 feature genes, 21 gene-pair signatures were developed to establish a metastasis-related prognosis risk-stratification model in ICC (EMLI-Prognosis). Based on EMLI-Prognosis algorithm, patients in the high-risk group had significantly dismal overall survival relative to the low-risk group in the clinical cohort (P-value < 0.05). Taken together, the EMLI-ICC algorithm provides a powerful and robust means for accurate metastasis prediction and risk stratification across proteome and transcriptome data types that is superior to currently used clinicopathological features in patients with ICC. Our developed algorithm could have profound implications not just in improved clinical care in cancer metastasis risk prediction, but also more broadly in machine-learning-based multi-cohort diagnosis method development. To make the EMLI-ICC algorithm easily accessible for clinical application, we established a web-based server for metastasis risk prediction (http://ibi.zju.edu.cn/EMLI/).


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Proteoma , Algoritmos , Colangiocarcinoma/genética , Aprendizado de Máquina , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos/patologia , Medição de Risco
12.
Clin Chem ; 70(6): 830-840, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38581343

RESUMO

BACKGROUND: Microsatellite instability (MSI) indicates DNA mismatch repair deficiency in certain types of cancer, such as colorectal cancer. The current gold standard technique, PCR-capillary electrophoresis (CE), requires matching normal samples and specialized instrumentation. We developed VarTrace, a rapid and low-cost quantitative PCR (qPCR) assay, to evaluate MSI using solely the tumor sample DNA, obviating the requirement for matching normal samples. METHODS: One hundred and one formalin-fixed paraffin-embedded (FFPE) tumor samples were tested using VarTrace and compared with the Promega OncoMate assay utilizing PCR-CE. Tumor percentage limit of detection was evaluated on contrived samples derived from clinical high MSI (MSI-H) samples. Analytical sensitivity, specificity, limit of detection, and input requirements were assessed using synthetic commercial reference standards. RESULTS: VarTrace successfully analyzed all 101 clinical FFPE samples, demonstrating 100% sensitivity and 98% specificity compared to OncoMate. It detected MSI-H with 97% accuracy down to 10% tumor. Analytical studies using synthetic samples showed a limit of detection of 5% variant allele frequency and a limit of input of 0.5 ng. CONCLUSIONS: This study validates VarTrace as a swift, accurate, and economical assay for MSI detection in samples with low tumor percentages without the need for matching normal DNA. VarTrace's capacity for highly sensitive MSI analysis holds potential for enhancing the efficiency of clinical work flows and broadening the availability of this test.


Assuntos
Instabilidade de Microssatélites , Humanos , Inclusão em Parafina , Neoplasias/genética , Neoplasias/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Neoplasias Colorretais/genética , Neoplasias Colorretais/diagnóstico , Sensibilidade e Especificidade , Eletroforese Capilar/métodos , Formaldeído , DNA de Neoplasias/genética , Limite de Detecção , Reação em Cadeia da Polimerase/métodos
13.
FASEB J ; 37(2): e22693, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36607250

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most common, heterogenous endocrine disorders and is the leading cause of ovulatory obstacle associated with abnormal folliculogenesis. Dysfunction of ovarian granulosa cells (GCs) is recognized as a major factor that underlies abnormal follicle maturation. Angiopoietin-like 4 (ANGPTL4) expression in GCs differs between patients with and without PCOS. However, the role and mechanism of ANGPTL4 in impaired follicular development are still poorly understood. Here, the case-control study was designed to investigate the predictive value of ANGPTL4 in PCOS while cell experiments in vitro were set for mechanism research. Results found that ANGPTL4 levels in serum and in follicular fluid, and its expression in GCs, were upregulated in patients with PCOS. In KGN and SVOG cells, upregulation of ANGPTL4 inhibited the proliferation of GCs by blocking G1/S cell cycle progression, as well as the molecular activation of the EGFR/JAK1/STAT3 cascade. Moreover, the STAT3-dependent CDKN1A(p21) promoter increased CDKN1A transcription, resulting in remarkable suppression effect on GCs. Together, our results demonstrated that overexpression of ANGPTL4 inhibited the proliferation of GCs through EGFR/JAK1/STAT3-mediated induction of p21, thus providing a novel epigenetic mechanism for the pathogenesis of PCOS.


Assuntos
Síndrome do Ovário Policístico , Feminino , Humanos , Síndrome do Ovário Policístico/metabolismo , Estudos de Casos e Controles , Células da Granulosa/metabolismo , Proliferação de Células , Receptores ErbB/metabolismo , Proteína 4 Semelhante a Angiopoietina/genética , Proteína 4 Semelhante a Angiopoietina/metabolismo , Proteína 4 Semelhante a Angiopoietina/farmacologia , Janus Quinase 1/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
14.
Pancreatology ; 24(2): 241-248, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38195328

RESUMO

BACKGROUND: To provide data on the safety and efficacy of a combination chemotherapy regimen consisting of S-1, oxaliplatin, and irinotecan (SOXIRI) as a first-line therapy in unresectable pancreatic ductal adenocarcinoma (UPDA) patients. METHODS: Patients with UPDA and no prior treatment chemotherapy in the UPDA setting were enrolled. The primary endpoint was the objective response rate (ORR). Secondary endpoints were overall survival (OS), progression-free survival (PFS) and adverse events. Patients received 80 mg/m2 S-1 twice a day for 2 weeks in an alternate-day administration cycle, 85 mg/m2 oxaliplatin on Day 1, and 150 mg/m2 irinotecan on Day 1 of a 2-week cycle. RESULTS: In these 62 enrolled patients, the ORR was 27.4 %, median OS was 12.1 months, and median PFS was 6.5 months. Major grade 3 or 4 toxicity included neutropenia (22.3 %), leucopenia (16.1 %), nausea (9.7 %), vomiting (9.7 %), thrombocytopenia (6.5 %), anorexia (8.5 %), anemia (4.8 %), and diarrhea (1.6 %). No treatment-related deaths occurred. In addition, the analysis of 32 patients suffering pain revealed that the rate of pain relief was 34.4 %. CONCLUSION: SOXIRI might be a standard regimen with an acceptable toxicity profile and favorable efficacy for use as chemotherapy in patients with UPDA.


Assuntos
Adenocarcinoma , Neutropenia , Neoplasias Pancreáticas , Humanos , Irinotecano , Oxaliplatina , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Dor
15.
Cell Commun Signal ; 22(1): 275, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755602

RESUMO

BACKGROUND: Diabetic retinopathy (DR) is a major cause of blindness and is characterized by dysfunction of the retinal microvasculature. Neutrophil stasis, resulting in retinal inflammation and the occlusion of retinal microvessels, is a key mechanism driving DR. These plugging neutrophils subsequently release neutrophil extracellular traps (NETs), which further disrupts the retinal vasculature. Nevertheless, the primary catalyst for NETs extrusion in the retinal microenvironment under diabetic conditions remains unidentified. In recent studies, cellular communication network factor 1 (CCN1) has emerged as a central molecule modulating inflammation in pathological settings. Additionally, our previous research has shed light on the pathogenic role of CCN1 in maintaining endothelial integrity. However, the precise role of CCN1 in microvascular occlusion and its potential interaction with neutrophils in diabetic retinopathy have not yet been investigated. METHODS: We first examined the circulating level of CCN1 and NETs in our study cohort and analyzed related clinical parameters. To further evaluate the effects of CCN1 in vivo, we used recombinant CCN1 protein and CCN1 overexpression for gain-of-function, and CCN1 knockdown for loss-of-function by intravitreal injection in diabetic mice. The underlying mechanisms were further validated on human and mouse primary neutrophils and dHL60 cells. RESULTS: We detected increases in CCN1 and neutrophil elastase in the plasma of DR patients and the retinas of diabetic mice. CCN1 gain-of-function in the retina resulted in neutrophil stasis, NETs extrusion, capillary degeneration, and retinal leakage. Pre-treatment with DNase I to reduce NETs effectively eliminated CCN1-induced retinal leakage. Notably, both CCN1 knockdown and DNase I treatment rescued the retinal leakage in the context of diabetes. In vitro, CCN1 promoted adherence, migration, and NETs extrusion of neutrophils. CONCLUSION: In this study, we uncover that CCN1 contributed to retinal inflammation, vessel occlusion and leakage by recruiting neutrophils and triggering NETs extrusion under diabetic conditions. Notably, manipulating CCN1 was able to hold therapeutic promise for the treatment of diabetic retinopathy.


Assuntos
Proteína Rica em Cisteína 61 , Retinopatia Diabética , Armadilhas Extracelulares , Camundongos Endogâmicos C57BL , Neutrófilos , Retinopatia Diabética/patologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/genética , Armadilhas Extracelulares/metabolismo , Animais , Neutrófilos/metabolismo , Humanos , Proteína Rica em Cisteína 61/metabolismo , Proteína Rica em Cisteína 61/genética , Camundongos , Masculino , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/complicações , Retina/patologia , Retina/metabolismo , Feminino , Pessoa de Meia-Idade
16.
Mol Pharm ; 21(1): 113-125, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081040

RESUMO

Although chemotherapy remains the standard therapy for tumor treatment, serious side effects can occur because of nontargeted distribution and damage to healthy tissues. Hollow mesoporous silica nanoparticles (HMSNs) modified with lipids offer potential as delivery systems to improve therapeutic outcomes and reduce adverse effects. Herein, we synthesized HMSNs with integrated disulfide bonds (HMSN) for loading with the chemotherapeutic agent oxaliplatin (OXP) which were then covered with the synthesized hypoxia-sensitive lipid (Lip) on the surface to prepare the dual-sensitive lipid-composite nanoparticles (HMSN-OXP-Lip). The empty lipid-composite nanoparticles (HMSN-Lip) would consume glutathione (GSH) in cells because of the reduction of disulfide bonds in HMSN and would also inhibit GSH production because of NADPH depletion driven by Lip cleavage. These actions contribute to increased levels of ROS that induce the immunogenic cell death (ICD) effect. Simultaneously, HMSN-Lip would disintegrate in the presence of high concentrations of GSH. The lipid in HMSN-OXP-Lip could evade payload leakage during blood circulation and accelerate the release of the OXP in the tumor region in the hypoxic microenvironment, which could significantly induce the ICD effect to activate an immune response for an enhanced therapeutic effect. The tumor inhibitory rate of HMSN-OXP-Lip was almost twice that of free OXP, and no apparent side effects were observed. This design provides a dual-sensitive and efficient strategy for tumor therapy by using lipid-composite nanoparticles that can undergo sensitive drug release and biodegradation.


Assuntos
Neoplasias da Mama , Neuropatia Hereditária Motora e Sensorial , Nanopartículas , Humanos , Feminino , Doxorrubicina , Morte Celular Imunogênica , Nanopartículas/química , Dióxido de Silício/química , Glutationa , Lipídeos , Neuropatia Hereditária Motora e Sensorial/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Dissulfetos , Linhagem Celular Tumoral , Microambiente Tumoral
17.
Diabetes Obes Metab ; 26(4): 1395-1406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38287130

RESUMO

AIM: Novel long-acting drugs for type 2 diabetes mellitus may optimize patient compliance and glycaemic control. Exendin-4-IgG4-Fc (E4F4) is a long-acting glucagon-like peptide-1 receptor agonist. This first-in-human study investigated the safety, tolerability, pharmacokinetic, pharmacodynamic and immunogenicity profiles of a single subcutaneous injection of E4F4 in healthy subjects. METHODS: This single-centre, randomized, double-blind, placebo-controlled phase 1 clinical trial included 96 subjects in 10 sequential cohorts that were provided successively higher doses of E4F4 (0.45, 0.9, 1.8, 3.15, 4.5, 6.3, 8.1, 10.35, 12.6 and 14.85 mg) or placebo (ChinaDrugTrials.org.cn: ChiCTR2100049732). The primary endpoint was safety and tolerability of E4F4. Secondary endpoints were pharmacokinetic, pharmacodynamic and immunogenicity profiles of E4F4. Safety data to day 15 after the final subject in a cohort had been dosed were reviewed before commencing the next dose level. RESULTS: E4F4 was safe and well tolerated among healthy Chinese participants in this study. There was no obvious dose-dependent relationship between frequency, severity or causality of treatment-emergent adverse events. Cmax and area under the curve of E4F4 were dose proportional over the 0.45-14.85 mg dose range. Median Tmax and t1/2 ranged from 146 to 210 h and 199 to 252 h, respectively, across E4F4 doses, with no dose-dependent trends. For the intravenous glucose tolerance test, area under the curve of glucose in plasma from time 0 to 180 min showed a dose-response relationship in the 1.8-10.35 mg dose range, with an increased response at the higher doses. CONCLUSION: E4F4 exhibited an acceptable safety profile and linear pharmacokinetics in healthy subjects. The recommended phase 2 dose is 4.5-10.35 mg once every 2 weeks.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Exenatida/efeitos adversos , Voluntários Saudáveis , Área Sob a Curva , Teste de Tolerância a Glucose , Método Duplo-Cego , Relação Dose-Resposta a Droga
18.
Int J Colorectal Dis ; 39(1): 110, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39009899

RESUMO

PURPOSE: Ulcerative colitis (UC) is an inflammatory bowel disease with an unclear etiology that can lead to irreversible changes in distal colonic function in chronic patients. This study investigated anorectal function in recurrent UC patients and identified influencing factors. METHODS: This prospective study enrolled 33 recurrent UC patients and 40 newly diagnosed patients from January 2019 to December 2022. Data collection included clinical records, scores, and anorectal function assessments. Regression analyses were used to identify factors impacting anorectal function. RESULTS: Recurrent UC patients had higher baseline CRP and fecal calprotectin levels, increased anxiety and depression, and more severe fecal incontinence. They also had lower BMIs, serum Hb and albumin (ALB) levels, and Inflammatory Bowel Disease Questionnaire scores than did initial-onset UC patients. Multivariate linear regression analysis revealed that long disease duration (coef. - 0.376, P < 0.001) and high fecal calprotectin level (coef. - 0.656, P < 0.001) independently influenced the initial sensation threshold in recurrent UC patients. Additionally, high fecal calprotectin (coef. - 0.073, P = 0.013) and high Zung Self-Rating Anxiety Scale score (coef. - 0.489, P = 0.001) were identified as two independent determinants of the defecation volume threshold. For the defecation urgency threshold, the independent factors included high disease duration (coef. - 0.358, P = 0.017) and high fecal calprotectin level (coef. - 0.499, P = 0.001). Similarly, the sole independent factor identified for the maximum capacity threshold was high fecal calprotectin (coef. - 0.691, P = 0.001). CONCLUSION: Recurrent UC patients had increased rectal sensitivity and compromised anorectal function, which significantly impacted quality of life. Proactively managing the disease, reducing UC relapses, and addressing anxiety are effective measures for improving anorectal function in these patients.


Assuntos
Canal Anal , Colite Ulcerativa , Fezes , Complexo Antígeno L1 Leucocitário , Reto , Recidiva , Humanos , Colite Ulcerativa/fisiopatologia , Colite Ulcerativa/psicologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Complexo Antígeno L1 Leucocitário/análise , Complexo Antígeno L1 Leucocitário/metabolismo , Fezes/química , Canal Anal/fisiopatologia , Reto/fisiopatologia , Defecação/fisiologia , Estudos Prospectivos , Incontinência Fecal/fisiopatologia , Incontinência Fecal/etiologia , Incontinência Fecal/psicologia , Ansiedade/fisiopatologia
19.
Surg Endosc ; 38(7): 3819-3827, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38811429

RESUMO

BACKGROUND: Upper gastrointestinal foreign body ingestion is a common digestive tract emergency, of which completely embedded ones were challenging for most endoscopists. We aim to evaluate the efficacy and safety of endoscopic submucosal fenestration in the treatment of completely embedded upper gastrointestinal foreign bodies. METHODS: From December 2018 to December 2021, 19 patients with completely embedded upper gastrointestinal foreign bodies who underwent endoscopic submucosal fenestration in Zhongshan Hospital, Fudan University were included. The safety, efficacy, and outcome were retrospectively reviewed. RESULTS: Among the 19 patients, 15 foreign bodies were embedded in the esophagus, 3 located in the gastric wall, and 1 located in the duodenal bulb. The foreign bodies were successfully managed in 12 cases, and 7 failed after attempts of repeated exploration. Two cases confirmed completely traversing into the mediastinum were successfully removed after transfer to surgery. One case had retrieval of a foreign body in a half-year examination. Till now, 3 failed patients had great relief of symptoms and only one patient claimed occasional thoracodynia. Of note, there were neither serious adverse events, nor long-term complications during the follow-up. CONCLUSION: In disposing of foreign bodies completely embedded in the upper gastrointestinal tract, ESF is a safe and effective alternative to surgery.


Assuntos
Corpos Estranhos , Humanos , Corpos Estranhos/cirurgia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem , Idoso , Trato Gastrointestinal Superior/cirurgia , Ressecção Endoscópica de Mucosa/métodos , Ressecção Endoscópica de Mucosa/efeitos adversos , Esôfago/cirurgia , Adolescente , Duodeno/cirurgia
20.
J Nanobiotechnology ; 22(1): 275, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778401

RESUMO

BACKGROUND: Acute gouty is caused by the excessive accumulation of Monosodium Urate (MSU) crystals within various parts of the body, which leads to a deterioration of the local microenvironment. This degradation is marked by elevated levels of uric acid (UA), increased reactive oxygen species (ROS) production, hypoxic conditions, an upsurge in pro-inflammatory mediators, and mitochondrial dysfunction. RESULTS: In this study, we developed a multifunctional nanoparticle of polydopamine-platinum (PDA@Pt) to combat acute gout by leveraging mild hyperthermia to synergistically enhance UA degradation and anti-inflammatory effect. Herein, PDA acts as a foundational template that facilitates the growth of a Pt shell on the surface of its nanospheres, leading to the formation of the PDA@Pt nanomedicine. Within this therapeutic agent, the Pt nanoparticle catalyzes the decomposition of UA and actively breaks down endogenous hydrogen peroxide (H2O2) to produce O2, which helps to alleviate hypoxic conditions. Concurrently, the PDA component possesses exceptional capacity for ROS scavenging. Most significantly, Both PDA and Pt shell exhibit absorption in the Near-Infrared-II (NIR-II) region, which not only endow PDA@Pt with superior photothermal conversion efficiency for effective photothermal therapy (PTT) but also substantially enhances the nanomedicine's capacity for UA degradation, O2 production and ROS scavenging enzymatic activities. This photothermally-enhanced approach effectively facilitates the repair of mitochondrial damage and downregulates the NF-κB signaling pathway to inhibit the expression of pro-inflammatory cytokines. CONCLUSIONS: The multifunctional nanomedicine PDA@Pt exhibits exceptional efficacy in UA reduction and anti-inflammatory effects, presenting a promising potential therapeutic strategy for the management of acute gout.


Assuntos
Gota , Indóis , Polímeros , Espécies Reativas de Oxigênio , Ácido Úrico , Gota/tratamento farmacológico , Gota/metabolismo , Gota/terapia , Espécies Reativas de Oxigênio/metabolismo , Animais , Camundongos , Polímeros/química , Indóis/química , Indóis/farmacologia , Nanopartículas/química , Platina/química , Platina/farmacologia , Platina/uso terapêutico , Humanos , Peróxido de Hidrogênio/metabolismo , Hipertermia Induzida/métodos , Células RAW 264.7 , Terapia Fototérmica/métodos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA