Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.701
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 121(24): e2321619121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38833475

RESUMO

Angiotensin-convertingenzyme 2 (ACE2) has dual functions, regulating cardiovascular physiology and serving as the receptor for coronaviruses. Bats, the only true flying mammals and natural viral reservoirs, have evolved positive alterations in traits related to both functions of ACE2. This suggests significant evolutionary changes in ACE2 during bat evolution. To test this hypothesis, we examine the selection pressure in ACE2 along the ancestral branch of all bats (AncBat-ACE2), where powered flight and bat-coronavirus coevolution occurred, and detect a positive selection signature. To assess the functional effects of positive selection, we resurrect AncBat-ACE2 and its mutant (AncBat-ACE2-mut) created by replacing the positively selected sites. Compared to AncBat-ACE2-mut, AncBat-ACE2 exhibits stronger enzymatic activity, enhances mice's performance in exercise fatigue, and shows lower affinity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our findings indicate the functional pleiotropy of positive selection in the ancient ACE2 of bats, providing an alternative hypothesis for the evolutionary origin of bats' defense against coronaviruses.


Assuntos
Enzima de Conversão de Angiotensina 2 , Quirópteros , Seleção Genética , Quirópteros/virologia , Quirópteros/genética , Animais , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Camundongos , Pleiotropia Genética , Evolução Molecular , SARS-CoV-2/genética , COVID-19/virologia , COVID-19/genética , Coronavirus/genética , Humanos , Filogenia
2.
Plant J ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39348559

RESUMO

Leaves, as primary photosynthetic organs essential for high crop yield and quality, have attracted significant attention. The functions of DNA topoisomerase 1α (TOP1α) in various biological processes, including leaf development, in Brassica napus remain unknown. Here, four paralogs of BnaTOP1α, namely BnaA01.TOP1α, BnaA02.TOP1α, BnaC01.TOP1α and BnaC02.TOP1α, were identified and cloned in the B. napus inbred line 'K407'. Expression pattern analysis revealed that BnaA02.TOP1α and BnaC02.TOP1α, but not BnaA01.TOP1α and BnaC01.TOP1α, were persistently and highly expressed in B. napus true leaves. Preliminary analysis in Arabidopsis thaliana revealed that BnaA02.TOP1α and BnaC02.TOP1α paralogs, but not BnaA01.TOP1α and BnaC01.TOP1α, performed biological functions. Targeted mutations of four BnaTOP1α paralogs in B. napus using the CRISPR-Cas9 system revealed that BnaA02.TOP1α and BnaC02.TOP1α served as functional paralogs and redundantly promoted true leaf number and size, thereby promoting true leaf biomass accumulation. Moreover, BnaA02.TOP1α modulated the levels of endogenous gibberellins, cytokinins and auxins by indirectly regulating several genes related to their metabolism processes. BnaA02.TOP1α directly activated BnaA03.CCS52A2 and BnaC09.AN3 by facilitating the recruitment of RNA polymerase II and modulating H3K27me3, H3K36me2 and H3K36me3 levels at these loci and indirectly activated the BnaA08.PARL1 expression, thereby positively controlling the true leaf size in B. napus. Additionally, BnaA02.TOP1α indirectly activated the BnaA07.PIN1 expression to positively regulate the true leaf number. These results reveal the important functions of BnaTOP1α and provide insights into the regulatory network controlling true leaf biomass accumulation in B. napus.

3.
Plant Physiol ; 195(4): 2997-3009, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38687890

RESUMO

Seed germination is a critical checkpoint for plant growth under unfavorable environmental conditions. In Arabidopsis (Arabidopsis thaliana), the abscisic acid (ABA) and gibberellic acid (GA) signaling pathways play important roles in modulating seed germination. However, the molecular links between salinity stress and ABA/GA signaling are not well understood. Herein, we showed that the expression of DIVARICATA1 (DIV1), which encodes a MYB-like transcription factor, was induced by GA and repressed by ABA, salinity, and osmotic stress in germinating seeds. DIV1 positively regulated seed germination in response to salinity stress by directly regulating the expression of DELAY OF GERMINATION 1-LIKE 3 (DOGL3) and GA-STIMULATED ARABIDOPSIS 4 (GASA4) and indirectly regulating the expression of several germination-associated genes. Moreover, NUCLEAR FACTOR-YC9 (NF-YC9) directly repressed the expression of DIV1 in germinating seeds in response to salinity stress. These results help reveal the function of the NF-YC9-DIV1 module and provide insights into the regulation of ABA and GA signaling in response to salinity stress during seed germination in Arabidopsis.


Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Germinação , Giberelinas , Estresse Salino , Sementes , Fatores de Transcrição , Germinação/efeitos dos fármacos , Germinação/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/efeitos dos fármacos , Sementes/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Giberelinas/metabolismo , Giberelinas/farmacologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transdução de Sinais , Salinidade , Pressão Osmótica
4.
Plant Cell ; 34(5): 1724-1744, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35137215

RESUMO

Plant innate immunity is capable of combating diverse and ever evolving pathogens. The plasticity of innate immunity could be boosted by RNA processing. Arabidopsis thaliana CONSTITUTIVE EXPRESSER OF PATHOGENESIS-RELATED GENES 5 (CPR5), a key negative immune regulator, is a component of the nuclear pore complex. Here we further identified CPR5 as a component of RNA processing complexes. Through genetic screening, we found that RNA splicing activator NineTeen Complex and RNA polyadenylation factor CLEAVAGE AND POLYADENYLATION SPECIFICITY FACTOR, coordinately function downstream of CPR5 to activate plant immunity. CPR5 and these two regulators form a complex that is localized in nuclear speckles, an RNA processing organelle. Intriguingly, we found that CPR5 is an RNA-binding protein belonging to the Transformer 2 (Tra2) subfamily of the serine/arginine-rich family. The RNA recognition motif of CPR5 protein binds the Tra2-targeted RNA sequence in vitro and is functionally replaceable by those of Tra2 subfamily proteins. In planta, it binds RNAs of CPR5-regulated alternatively spliced genes (ASGs) identified by RNA-seq. ARGONAUTE 1 (AGO1) is one of the ASGs and, consistent with this, the ago1 mutant suppresses the cpr5 phenotype. These findings reveal that CPR5 is an RNA-binding protein linking RNA processing with plant immunity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Membrana/metabolismo , Imunidade Vegetal/genética , Processamento Pós-Transcricional do RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
5.
Breast Cancer Res ; 26(1): 18, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287356

RESUMO

BACKGROUNDS: Since breast cancer patients respond diversely to immunotherapy, there is an urgent need to explore novel biomarkers to precisely predict clinical responses and enhance therapeutic efficacy. The purpose of our present research was to construct and independently validate a biomarker of tumor microenvironment (TME) phenotypes via a machine learning-based radiomics way. The interrelationship between the biomarker, TME phenotypes and recipients' clinical response was also revealed. METHODS: In this retrospective multi-cohort investigation, five separate cohorts of breast cancer patients were recruited to measure breast cancer TME phenotypes via a radiomics signature, which was constructed and validated by integrating RNA-seq data with DCE-MRI images for predicting immunotherapy response. Initially, we constructed TME phenotypes using RNA-seq of 1089 breast cancer patients in the TCGA database. Then, parallel DCE-MRI images and RNA-seq of 94 breast cancer patients obtained from TCIA were applied to develop a radiomics-based TME phenotypes signature using random forest in machine learning. The repeatability of the radiomics signature was then validated in an internal validation set. Two additional independent external validation sets were analyzed to reassess this signature. The Immune phenotype cohort (n = 158) was divided based on CD8 cell infiltration into immune-inflamed and immune-desert phenotypes; these data were utilized to examine the relationship between the immune phenotypes and this signature. Finally, we utilized an Immunotherapy-treated cohort with 77 cases who received anti-PD-1/PD-L1 treatment to evaluate the predictive efficiency of this signature in terms of clinical outcomes. RESULTS: The TME phenotypes of breast cancer were separated into two heterogeneous clusters: Cluster A, an "immune-inflamed" cluster, containing substantial innate and adaptive immune cell infiltration, and Cluster B, an "immune-desert" cluster, with modest TME cell infiltration. We constructed a radiomics signature for the TME phenotypes ([AUC] = 0.855; 95% CI 0.777-0.932; p < 0.05) and verified it in an internal validation set (0.844; 0.606-1; p < 0.05). In the known immune phenotypes cohort, the signature can identify either immune-inflamed or immune-desert tumor (0.814; 0.717-0.911; p < 0.05). In the Immunotherapy-treated cohort, patients with objective response had higher baseline radiomics scores than those with stable or progressing disease (p < 0.05); moreover, the radiomics signature achieved an AUC of 0.784 (0.643-0.926; p < 0.05) for predicting immunotherapy response. CONCLUSIONS: Our imaging biomarker, a practicable radiomics signature, is beneficial for predicting the TME phenotypes and clinical response in anti-PD-1/PD-L1-treated breast cancer patients. It is particularly effective in identifying the "immune-desert" phenotype and may aid in its transformation into an "immune-inflamed" phenotype.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Radiômica , Antígeno B7-H1/genética , Estudos Retrospectivos , Microambiente Tumoral/genética , Fenótipo , Imunoterapia , Aprendizado de Máquina , Biomarcadores
6.
Anal Chem ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39376149

RESUMO

Keloids represent pathologic conditions characterized by the presence of hyalinized collagen bundles and chronic inflammatory reactions. Recently, increased ROS production and disrupted apoptosis mechanisms in keloids have been reported, although the detailed mechanisms remain unclear. Herein, we developed a specific fluorescence probe, Pro-NBS, to investigate ClO- levels in keloids. The probe demonstrated high specificity for ClO- over other ROS and exhibited a strong linear detection relationship. Based on its performance, we focused on the TGF-ß pathway in the development of keloids. ROS upregulation was observed in keloid-derived fibroblasts. Using ClO- as an intrinsic overexpression marker, our probe effectively distinguished between normal fibroblasts and keloid-derived fibroblasts both in vitro and in vivo. Furthermore, Pro-NBS showed potential for monitoring the progression and evaluating the systematic therapy of abnormal scarring or keloids.

7.
Anal Chem ; 96(37): 14800-14808, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39213642

RESUMO

Mitochondrial polarity is a critical indicator of numerous pathological and biological processes; thus, the development of fluorescent probes capable of targeting mitochondria and visually monitoring its polarity is of great significance. In this study, fluorescent probes were designed with a N, N-dialkylamino rhodol scaffold as the fluorophore sensitive to polarity environments, in which the alkyl chain length was adjusted rationally to obtain distinct polarity recognition modes. By integrating mitochondria targeting groups, three fluorogenic chemical probes ROML-1, ROML-2, and ROML-3 have been obtained, featuring the capability to target mitochondria and monitor its polarity precisely, dynamically and visually. The probes displayed a distinctive response to the alterations in polarity. ROML-1 and ROML-2 followed a turn-on pattern while ROML-3 was ratiometric. It has been demonstrated that the hypersensitivity to polarity and ratio fluorescence property of ROML-3 was attributed to methyl groups rather than ethyl or butyl groups. The introduction of short methyl chains made the dihedral angle between the dialkylamino substituent and fluorophore of ROML-3 (spirocyclic form) rotatable and enlarged the energy gap between the ground state and excited state, which has been validated by the results of density functional theory (DFT) calculations. Furthermore, ROML-3 was used to monitor mitochondrial polarity via confocal microscopy imaging, which revealed that compared to healthy cells the polarity of mitochondria in cancer cells was enhanced; meanwhile, the polarity of mitochondria in senescent cells was higher in contrast with young cells. The present probe ROML-3 has been proven to be an efficient tool to monitor mitochondrial polarity dynamics, which demonstrated potential significance in biomedical research and disease diagnosis.


Assuntos
Corantes Fluorescentes , Mitocôndrias , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Mitocôndrias/química , Humanos , Teoria da Densidade Funcional , Estrutura Molecular , Imagem Óptica , Células HeLa
8.
Small ; 20(22): e2307961, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38126911

RESUMO

Activating the stimulator of the interferon gene (STING) is a promising immunotherapeutic strategy for converting "cold" tumor microenvironment into "hot" one to achieve better immunotherapy for malignant tumors. Herein, a manganese-based nanotransformer is presented, consisting of manganese carbonyl and cyanine dye, for MRI/NIR-II dual-modality imaging-guided multifunctional carbon monoxide (CO) gas treatment and photothermal therapy, along with triggering cGAS-STING immune pathway against triple-negative breast cancer. This nanosystem is able to transfer its amorphous morphology into a crystallographic-like formation in response to the tumor microenvironment, achieved by breaking metal-carbon bonds and forming coordination bonds, which enhances the sensitivity of magnetic resonance imaging. Moreover, the generated CO and photothermal effect under irradiation of this nanotransformer induce immunogenic death of tumor cells and release damage-associated molecular patterns. Simultaneously, the Mn acts as an immunoactivator, potentially stimulating the cGAS-STING pathway to augment adaptive immunity, resulting in promoting the secretion of type I interferon, the proliferation of cytotoxic T lymphocytes and M2-macrophages repolarization. This nanosystem-based gas-photothermal treatment and immunoactivating therapy synergistic effect exhibit excellent antitumor efficacy both in vitro and in vivo, reducing the risk of triple-negative breast cancer recurrence and metastasis; thus, this strategy presents great potential as multifunctional immunotherapeutic agents for cancer treatment.


Assuntos
Imunoterapia , Manganês , Terapia Fototérmica , Neoplasias de Mama Triplo Negativas , Neoplasias de Mama Triplo Negativas/terapia , Imunoterapia/métodos , Manganês/química , Humanos , Animais , Terapia Fototérmica/métodos , Linhagem Celular Tumoral , Feminino , Imageamento por Ressonância Magnética/métodos , Camundongos , Microambiente Tumoral , Nanopartículas/química , Fototerapia/métodos
9.
New Phytol ; 241(2): 764-778, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37904576

RESUMO

Bioactive triterpenes feature complex fused-ring structures, primarily shaped by the first-committed enzyme, 2,3-oxidosqualene cyclases (OSCs) in plant triterpene biosynthesis. Triterpenes with B,C-ring-opened skeletons are extremely rare with unknown formation mechanisms, harbouring unchartered chemistry and biology. Here, through mining the genome of Chenopodium quinoa followed by functional characterization, we identified a stress-responsive and neofunctionalized OSC capable of generating B,C-ring-opened triterpenes, including camelliol A and B and the novel (-)-quinoxide A as wax components of the specialized epidermal bladder cells, namely the quinoxide synthase (CqQS). Protein structure analysis followed by site-directed mutagenesis identified key variable amino acid sites underlying functional interconversion between pentacyclic ß-amyrin synthase (CqbAS1) and B,C-ring-opened triterpene synthase CqQS. Mutation of one key residue (N612K) in even evolutionarily distant Arabidopsis ß-amyrin synthase could generate quinoxides, indicating a conserved mechanism for B,C-ring-opened triterpene formation in plants. Quantum computation combined with docking experiments further suggests that conformations of conserved W613 and F413 of CqQS might be key to selectively stabilizing intermediate carbocations towards B,C-ring-opened triterpene formation. Our findings shed light on quinoa triterpene skeletal diversity and mechanisms underlying B,C-ring-opened triterpene biosynthesis, opening avenues towards accessing their chemistry and biology and paving the way for quinoa trait engineering and quality improvement.


Assuntos
Chenopodium quinoa , Transferases Intramoleculares , Triterpenos , Chenopodium quinoa/metabolismo , Triterpenos/metabolismo , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo
10.
Plant Physiol ; 192(1): 488-503, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36542529

RESUMO

Leaf senescence is the final stage of leaf development and is affected by various exogenous and endogenous factors. Transcriptional regulation is essential for leaf senescence, however, the underlying molecular mechanisms remain largely unclear. In this study, we report that the transcription factor MYB59, which was predominantly expressed in early senescent rosette leaves, negatively regulates leaf senescence in Arabidopsis (Arabidopsis thaliana). RNA sequencing revealed a large number of differentially expressed genes involved in several senescence-related biological processes in myb59-1 rosette leaves. Chromatin immunoprecipitation and transient dual-luciferase reporter assays demonstrated that MYB59 directly repressed the expression of SENESCENCE ASSOCIATED GENE 18 and indirectly inhibited the expression of several other senescence-associated genes to delay leaf senescence. Moreover, MYB59 was induced by salicylic acid (SA) and jasmonic acid (JA). MYB59 inhibited SA production by directly repressing the expression of ISOCHORISMATE SYNTHASE 1 and PHENYLALANINE AMMONIA-LYASE 2 and restrained JA biosynthesis by directly suppressing the expression of LIPOXYGENASE 2, thus forming two negative feedback regulatory loops with SA and JA and ultimately delaying leaf senescence. These results help us understand the novel function of MYB59 and provide insights into the regulatory network controlling leaf senescence in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Senescência Vegetal , Ácido Salicílico/metabolismo , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas
11.
Eur J Clin Invest ; 54(6): e14179, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38363025

RESUMO

BACKGROUND: Emerging data suggested that lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease. Previous studies indicated fibrinogen (Fib) had synergetic effect on Lp(a)-induced events. However, combined impact of Fib and Lp(a) on ischemic stroke has not been elucidated. METHODS: In this prospective study, we consecutively enrolled 8263 patients with stable coronary artery diseases (CAD) from 2011 to 2017. Patients were categorized into three groups according to tertiles of Lp(a) levels [Lp(a)-low, Lp(a)-medium, and Lp(a)-high] and further divided into nine groups by Lp(a) and Fib levels. All subjects were followed up for the occurrence of ischemic stroke. RESULTS: During a median follow-up of 37.7 months, 157 (1.9%) ischemic strokes occurred. Stroke incidence increased by Lp(a) (1.1 vs. 2.1 vs. 2.5%, Cochran-Armitage p < .001) and Fib (1.1 vs. 2.0 vs. 2.6%, Cochran-Armitage p < .001) categories. When further classified into nine groups by Lp(a) and Fib levels, the incidence of ischemic stroke in group 9 [Lp(a)-high and Fib-high] was significantly higher than that in group 1 [Lp(a)-low and Fib-low] (3.1 vs. 6%, p < .001). The group 9 was associated with a highest risk for ischemic stroke (adjusted HR 4.907, 95% CI: 2.154-11.18, p < .001), compared with individuals in the Lp(a)-high (adjusted HR 2.290, 95% CI: 1.483-3.537, p < .001) or Fib-high (adjusted HR 1.184, 95% CI: 1.399-3.410, p = .001). Furthermore, combining Lp(a) with Fib increased C-statistics by .045 (p = .004). CONCLUSIONS: Current study first demonstrated that elevated Lp(a) combining with Fib evaluation enhanced the risk of ischemic stroke in patients with CAD beyond Lp(a) or Fib alone.


Assuntos
Doença da Artéria Coronariana , Fibrinogênio , AVC Isquêmico , Lipoproteína(a) , Humanos , Lipoproteína(a)/sangue , Lipoproteína(a)/metabolismo , Fibrinogênio/metabolismo , Masculino , Feminino , Doença da Artéria Coronariana/epidemiologia , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , AVC Isquêmico/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Incidência , Fatores de Risco
12.
BMC Cancer ; 24(1): 1120, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251968

RESUMO

BACKGROUND: Transcatheter arterial chemoembolization (TACE) combined with targeted therapy and immunotherapy can significantly improve the prognosis of patients with hepatocellular carcinoma (HCC). T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is a novel immunosuppressive molecule. This study aimed to analyze the clinical correlation between TIGIT expression on T cells and patients with HCC. METHODS: Clinical data from 140 patients with HCC were retrospectively collected, and TIGIT expression on T cells was examined in each patient. Patients were subsequently divided into high- and low-expression groups, and their prognosis was analyzed. RESULTS: Patients with a high TIGIT expression on their T cells at baseline had a larger tumor volume, later staging, higher proportion of regulatory T cells, higher blood concentrations of interleukin (IL)-6 and IL-10, and lower interferon-γ concentrations. Following TACE, CD155 concentration decreased; however, TACE did not affect TIGIT expression on T cells. Additionally, among patients receiving TACE combined with apatinib and camrelizumab treatment, patients with a high TIGIT expression on T cells had significantly shorter progression-free survival (PFS) and overall survival times than those of patients in the low-expression group. Patients receiving TACE combined with apatinib and camrelizumab treatment with higher TIGIT expression have shorter PFS time than those receiving TACE combined with apatinib treatment. CONCLUSIONS: Patients with HCC that have a high TIGIT expression on their T cells exhibited poorer baseline characteristics, immunosuppressive status, and prognosis after receiving TACE combined with apatinib and camrelizumab and maybe more suited to receive TACE combined with apatinib treatment instead.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Receptores Imunológicos , Humanos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Masculino , Feminino , Prognóstico , Receptores Imunológicos/metabolismo , Pessoa de Meia-Idade , Estudos Retrospectivos , Quimioembolização Terapêutica/métodos , Idoso , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto , Receptores Virais/metabolismo
13.
Pharmacol Res ; 208: 107388, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39243915

RESUMO

Scientific risk assessment of exogenous and endogenous toxic substances in traditional Chinese medicine (TCM) is of great significance. The present review comprises a comprehensive summary of progress in the health risk assessment of harmful exogenous substances in TCMs. Such substances include heavy metals, pesticide residues, biotoxins, and endogenous toxic components involving pyrrolizidine alkaloids. The review also discusses the strengths and weaknesses of various bioaccessibility and bioavailability models, and their applications in risk assessment. Future avenues of risk assessment research are highlighted, including further exploration of risk assessment parameters, innovation of bioaccessibility and bioavailability techniques, enhancement of probabilistic risk assessment combined with bioavailability, improvement of cumulative risk assessment strategies, and formulation of strategies for reducing relative bioavailability (RBA) values in TCMs. Such efforts represent an attempt to develop a risk assessment system that is capable of evaluating the exogenous and endogenous toxic substances in TCMs to ensure its safe use in clinics, and to promote the sustainable development of the TCM industry.


Assuntos
Disponibilidade Biológica , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medição de Risco , Humanos , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/toxicidade , Medicamentos de Ervas Chinesas/efeitos adversos , Animais , Resíduos de Praguicidas/farmacocinética , Resíduos de Praguicidas/toxicidade , Resíduos de Praguicidas/análise , Metais Pesados
14.
Eur Radiol ; 34(2): 899-913, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37597033

RESUMO

OBJECTIVE: This study aimed to establish a MRI-based deep learning radiomics (DLR) signature to predict the human epidermal growth factor receptor 2 (HER2)-low-positive status and further verified the difference in prognosis by the DLR model. METHODS: A total of 481 patients with breast cancer who underwent preoperative MRI were retrospectively recruited from two institutions. Traditional radiomics features and deep semantic segmentation feature-based radiomics (DSFR) features were extracted from segmented tumors to construct models separately. Then, the DLR model was constructed to assess the HER2 status by averaging the output probabilities of the two models. Finally, a Kaplan‒Meier survival analysis was conducted to explore the disease-free survival (DFS) in patients with HER2-low-positive status. The multivariate Cox proportional hazard model was constructed to further determine the factors associated with DFS. RESULTS: First, the DLR model distinguished between HER2-negative and HER2-overexpressing patients with AUCs of 0.868 and 0.763 in the training and validation cohorts, respectively. Furthermore, the DLR model distinguished between HER2-low-positive and HER2-zero patients with AUCs of 0.855 and 0.750, respectively. Cox regression analysis showed that the prediction score obtained using the DLR model (HR, 0.175; p = 0.024) and lesion size (HR, 1.043; p = 0.009) were significant, independent predictors of DFS. CONCLUSIONS: We successfully constructed a DLR model based on MRI to noninvasively evaluate the HER2 status and further revealed prospects for predicting the DFS of patients with HER2-low-positive status. CLINICAL RELEVANCE STATEMENT: The MRI-based DLR model could noninvasively identify HER2-low-positive status, which is considered a novel prognostic predictor and therapeutic target. KEY POINTS: • The DLR model effectively distinguished the HER2 status of breast cancer patients, especially the HER2-low-positive status. • The DLR model was better than the traditional radiomics model or DSFR model in distinguishing HER2 expression. • The prediction score obtained using the model and lesion size were significant independent predictors of DFS.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Intervalo Livre de Doença , Estudos Retrospectivos , Radiômica , Imageamento por Ressonância Magnética
15.
Inorg Chem ; 63(15): 6734-6742, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38570330

RESUMO

The design of multimetal catalysts holds immense significance for efficient CO2 capture and its conversion into economically valuable chemicals. Herein, heterobimetallic catalysts (MiMo)L were exploited for the CO2 reduction reactions (CO2RR) using relativistic density functional theory (DFT). The octadentate Pacman-like polypyrrolic ligand (H4L) accommodates two metal ions (Mo, W, Nd, and U) inside (Mi) and outside (Mo) its month, rendering a weak bimetal coupling-assisted MN4 catalytically active site. Adsorption reactions have access to energetically stable coordination modes of -OCO, -OOC, and -(OCO)2, where the donor atom(s) are marked in bold. Among all of the species, (UiMoo)L releases the most energy. Along CO2RR, it favors to produce CO. The high-efficiency CO2 reduction is attributed to the size matching of U with the ligand mouth and the effective manipulation of the electron density of both ligand and bimetals. The mechanism in which heterobimetals synergetically capture and reduce CO2 has been postulated. This establishes a reference in elaborating on the complicated heterogeneous catalysis.

16.
Inorg Chem ; 63(8): 3870-3881, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38356223

RESUMO

Metal-organic frameworks (MOFs) have shown promising potential as proton-conducting materials due to their tunable structures and high porosity. In this study, two novel MOFs had been successfully synthesized, one containing sulfate groups (MOF-1; [Zn4(TIPE)2(SO4)4(H2O)]·5H2O) and the other containing sulfonate groups (MOF-2; [Zn2(TIPE)(5-sip)(NO3)0.66]·0.34NO3·17.5H2O) (TIPE = 1,1,2,2-tetrakis(4-(1H-imidazole-1-yl)phenyl)ethene, H35-sip = 5-sulfoisophthalicacid), and the effect of the two groups on the proton conductivity of Zn-based MOFs had been investigated and compared for the first time. The proton conductivity of these MOFs was systematically measured at different temperatures and humidity conditions. Remarkably, the results revealed significant differences in proton conductivity between the two sets of MOFs. At 90 °C and 98% RH, MOF-1 and MOF-2 achieved optimal proton conductivity of 4.48 × 10-3 and 5.69 × 10-2 S·cm-1, respectively. This was due to the structural differences arising from the presence of different functional groups, which subsequently affected the porosity and hydrophilicity, thereby influencing the proton conductivity. Overall, this comparative study revealed the influence of sulfate and sulfonate groups on the proton conductivity of Zn-based MOFs. This research provided a feasible idea for the development of advanced MOF materials with enhanced proton conductivity and opened up new possibilities for their application in proton devices.

17.
Cell Mol Biol (Noisy-le-grand) ; 70(7): 174-179, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39097877

RESUMO

AGO2 plays a vital role in small RNA-guided gene silencing, which has been implied in the tumorigenesis of different types of tumors. Fundamentally, increased expression of AGO2 protein is associated with cancer progression and metastasis. This study aims to investigate the molecular mechanism by which AGO2 promotes tumorigenesis in colorectal cancer (CRC). Databases were used to analyze the expression levels of AGO2 in CRC and confirmed by a quantitative reverse transcriptase-PCR (qRT-PCR) assay in CRC tissues and normal adjacent tissues collected from 25 CRC patients. CRISPR/Cas9-mediated genome editing was used to knockout the AGO2 in HCT116 cells as a model system for colorectal cancers. The cell proliferation, migration and invasion ability of HCT116 cells were detected by CCK-8 assay, Wound scratch assay and Transwell assay. Moreover, the quantities of miRNA binding with AGO2 were detected by RNA-Binding Protein Immunoprecipitation (RIP-Assay). We demonstrated that AGO2 was aberrantly high-expressed in 25 matched-tissue pairs of colorectal cancer and para-carcinoma tissue. The following functional experiments verified that knockout of AGO2 suppressed cell proliferation, migration and tumorigenesis to hamper the aggressiveness of CRC. Our study also suggests a possible link between AGO2 and miRNA in RISC. AGO2 was elevated in CRC and knockout of AGO2 suppressed proliferation and tumorigenicity of CRC cells. Moreover, RISC formation and the function of miRNAs are also subject to AGO2. AGO2 may be a meaningful target for CRC therapy.


Assuntos
Proteínas Argonautas , Sistemas CRISPR-Cas , Carcinogênese , Movimento Celular , Proliferação de Células , Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Humanos , Proteínas Argonautas/metabolismo , Proteínas Argonautas/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Proliferação de Células/genética , Sistemas CRISPR-Cas/genética , Movimento Celular/genética , Carcinogênese/genética , Carcinogênese/patologia , Células HCT116 , MicroRNAs/genética , MicroRNAs/metabolismo , Técnicas de Inativação de Genes
18.
Phys Chem Chem Phys ; 26(19): 14336-14344, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38699833

RESUMO

Investigating the effects of electrolyte ions on the adsorption configuration of methanol at a charged interface is important for studying the interface structure of electrolyte solutions and the oxidation mechanism of methanol in fuel cells. This study uses sum frequency generation (SFG) and heterodyne-detected second harmonic generation (HD-SHG) to investigate the adsorption configuration of methanol at the air/aqueous interface of 0.1 M NaClO4 solution, 0.1 M HClO4 solution and pure water. The results elucidate that the ion effect in the electrolyte solution affects the interface's charged state and the methanol's adsorption conformation at the interface. The negatively charged surface of the 0.1 M NaClO4 solution and the positively charged surface of the 0.1 M HClO4 solution arise from the corresponding specific ionic effects of the electrolyte solution. The orientation angle of methyl with respect to the surface normal is 43.4° ± 0.1° at the 0.1 M NaClO4 solution surface and 21.5° ± 0.2° at the 0.1 M HClO4 solution surface. Examining these adsorption configurations in detail, we find that at the negatively charged surface the inclined orientation angle (43.4°) of methanol favors the hydroxymethyl production by breaking the C-H bond, while at the positively charged surface the upright orientation angle (21.5°) of methanol promotes the methoxy formation by breaking the O-H bond. These findings not only illuminate the intricate ion effects on small organic molecules but also contribute to a molecular-level comprehension of the oxidation mechanism of methanol at electrode interfaces.

19.
J Nat Prod ; 87(7): 1786-1797, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38986603

RESUMO

Carabranolides present characteristic NMR resonances for the cyclopropane moiety, which distinctly differ from those of other compounds and were used for an NMR-guided isolation in this study. As a result, 11 undescribed carabranolides (1-11), along with five known ones (12-16), were isolated from the fruits of Carpesium abrotanoides L. Compounds 1-11 are new esters of carabrol at C-4 with different carboxylic acids. Their structures were elucidated by HRESIMS and NMR spectroscopic data analysis. The biological evaluation showed that compounds 2-4, 15, and 16 exhibited significant inhibitory activity against LPS-induced NO release with an IC50 value of 5.6-9.1 µM and dose-dependently decreased iNOS protein expression in RAW264.7 cells.


Assuntos
Anti-Inflamatórios , Asteraceae , Frutas , Óxido Nítrico , Animais , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Asteraceae/química , Frutas/química , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Células RAW 264.7 , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
20.
Bioorg Chem ; 143: 106998, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38035513

RESUMO

Androgen receptor (AR) plays a crucial role in various physiological processes. Dysregulation of AR signaling has been implicated in several diseases, such as prostate cancer and androgenetic alopecia. Therefore, the development of drugs that specifically target AR has gained significant attention in the field of drug discovery. This review provides an overview of the synthetic routes of clinically approved small molecule drugs targeting AR and discusses the clinical applications of these drugs in the treatment of AR-related diseases. The review also highlights the challenges and future perspectives in this field, including the need for improved drug design and the exploration of novel therapeutic targets. Through an integrated analysis of the therapeutic applications, synthetic methodologies, and mechanisms of action associated with these approved drugs, this review facilitates a holistic understanding of the versatile roles and therapeutic potential of AR-targeted interventions. Overall, this comprehensive review serves as a valuable resource for medicinal chemists interested in the development of small-molecule drugs targeting AR.


Assuntos
Neoplasias da Próstata , Receptores Androgênicos , Masculino , Humanos , Neoplasias da Próstata/tratamento farmacológico , Descoberta de Drogas , Desenho de Fármacos , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA