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1.
Nature ; 634(8033): 482-491, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39261729

RESUMO

The licensing step of DNA double-strand break repair by homologous recombination entails resection of DNA ends to generate a single-stranded DNA template for assembly of the repair machinery consisting of the RAD51 recombinase and ancillary factors1. DNA end resection is mechanistically intricate and reliant on the tumour suppressor complex BRCA1-BARD1 (ref. 2). Specifically, three distinct nuclease entities-the 5'-3' exonuclease EXO1 and heterodimeric complexes of the DNA endonuclease DNA2, with either the BLM or WRN helicase-act in synergy to execute the end resection process3. A major question concerns whether BRCA1-BARD1 directly regulates end resection. Here, using highly purified protein factors, we provide evidence that BRCA1-BARD1 physically interacts with EXO1, BLM and WRN. Importantly, with reconstituted biochemical systems and a single-molecule analytical tool, we show that BRCA1-BARD1 upregulates the activity of all three resection pathways. We also demonstrate that BRCA1 and BARD1 harbour stand-alone modules that contribute to the overall functionality of BRCA1-BARD1. Moreover, analysis of a BARD1 mutant impaired in DNA binding shows the importance of this BARD1 attribute in end resection, both in vitro and in cells. Thus, BRCA1-BARD1 enhances the efficiency of all three long-range DNA end resection pathways during homologous recombination in human cells.


Assuntos
Proteína BRCA1 , Quebras de DNA de Cadeia Dupla , Exodesoxirribonucleases , Recombinação Homóloga , RecQ Helicases , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Humanos , Proteína BRCA1/metabolismo , Proteína BRCA1/genética , DNA/metabolismo , DNA/genética , DNA Helicases , Reparo do DNA , Enzimas Reparadoras do DNA , DNA de Cadeia Simples/metabolismo , Exodesoxirribonucleases/metabolismo , Ligação Proteica , Rad51 Recombinase/metabolismo , Reparo de DNA por Recombinação , RecQ Helicases/metabolismo , RecQ Helicases/genética , Imagem Individual de Molécula , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/metabolismo , Regulação para Cima , Helicase da Síndrome de Werner/metabolismo , Helicase da Síndrome de Werner/genética
2.
Nature ; 619(7970): 640-649, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37344589

RESUMO

Homologous recombination (HR) fulfils a pivotal role in the repair of DNA double-strand breaks and collapsed replication forks1. HR depends on the products of several paralogues of RAD51, including the tetrameric complex of RAD51B, RAD51C, RAD51D and XRCC2 (BCDX2)2. BCDX2 functions as a mediator of nucleoprotein filament assembly by RAD51 and single-stranded DNA (ssDNA) during HR, but its mechanism remains undefined. Here we report cryogenic electron microscopy reconstructions of human BCDX2 in apo and ssDNA-bound states. The structures reveal how the amino-terminal domains of RAD51B, RAD51C and RAD51D participate in inter-subunit interactions that underpin complex formation and ssDNA-binding specificity. Single-molecule DNA curtain analysis yields insights into how BCDX2 enhances RAD51-ssDNA nucleoprotein filament assembly. Moreover, our cryogenic electron microscopy and functional analyses explain how RAD51C alterations found in patients with cancer3-6 inactivate DNA binding and the HR mediator activity of BCDX2. Our findings shed light on the role of BCDX2 in HR and provide a foundation for understanding how pathogenic alterations in BCDX2 impact genome repair.


Assuntos
Proteínas de Ligação a DNA , Recombinação Homóloga , Complexos Multiproteicos , Humanos , Microscopia Crioeletrônica , Replicação do DNA , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , DNA de Cadeia Simples/ultraestrutura , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/ultraestrutura , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Complexos Multiproteicos/ultraestrutura , Neoplasias/genética , Nucleoproteínas/metabolismo , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Rad51 Recombinase/química , Rad51 Recombinase/metabolismo , Rad51 Recombinase/ultraestrutura , Especificidade por Substrato
3.
Nucleic Acids Res ; 51(13): 6634-6653, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37254808

RESUMO

Mammalian erythroid development can be divided into three stages: hematopoietic stem and progenitor cell (HSPC), erythroid progenitor (Ery-Pro), and erythroid precursor (Ery-Pre). However, the mechanisms by which the 3D genome changes to establish the stage-specific transcription programs that are critical for erythropoiesis remain unclear. Here, we analyze the chromatin landscape at multiple levels in defined populations from primary human erythroid culture. While compartments and topologically associating domains remain largely unchanged, ∼50% of H3K27Ac-marked enhancers are dynamic in HSPC versus Ery-Pre. The enhancer anchors of enhancer-promoter loops are enriched for occupancy of respective stage-specific transcription factors (TFs), indicating these TFs orchestrate the enhancer connectome rewiring. The master TF of erythropoiesis, GATA1, is found to occupy most erythroid gene promoters at the Ery-Pro stage, and mediate conspicuous local rewiring through acquiring binding at the distal regions in Ery-Pre, promoting productive erythroid transcription output. Knocking out GATA1 binding sites precisely abrogates local rewiring and corresponding gene expression. Interestingly, knocking down GATA1 can transiently revert the cell state to an earlier stage and prolong the window of progenitor state. This study reveals mechanistic insights underlying chromatin rearrangements during development by integrating multidimensional chromatin landscape analyses to associate with transcription output and cellular states.


Assuntos
Cromatina , Eritropoese , Fator de Transcrição GATA1 , Animais , Humanos , Diferenciação Celular , Cromatina/genética , Fator de Transcrição GATA1/genética , Fator de Transcrição GATA1/metabolismo , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/genética
4.
Plant J ; 114(3): 570-590, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36815286

RESUMO

Leaf senescence involves massive multidimensional alterations, such as nutrient redistribution, and is closely related to crop yield and quality. No apical meristem, Arabidopsis transcription activation factor, and Cup-shaped cotyledon (NAC)-type transcription factors integrate various signals and modulate an enormous number of target genes to ensure the appropriate progression of leaf senescence. However, few leaf senescence-related NACs have been functionally characterized in wheat. Based on our previous RNA-sequencing (RNA-seq) data, we focused on a NAC family member, TaNAC69-B, which is increasingly expressed during leaf senescence in wheat. Overexpression of TaNAC69-B led to precocious leaf senescence in wheat and Arabidopsis, and affected several agricultural traits in transgenic wheat. Moreover, impaired expression of TaNAC69-B by virus-induced gene silencing retarded the leaf senescence in wheat. By RNA-seq and quantitative real-time polymerase chain reaction analysis, we confirmed that some abscisic acid (ABA) biosynthesis genes, including AAO3 and its ortholog in wheat, TraesCS2B02G270600 (TaAO3-B), were elevated by the overexpression of TaNAC69-B. Consistently, we observed more severe ABA-induced leaf senescence in TaNAC69-B-OE wheat and Arabidopsis plants. Furthermore, we determined that TaNAC69-B bound to the NAC binding site core (CGT) on the promoter regions of AAO3 and TaAO3-B. Moreover, we confirmed elevated ABA levels in TaNAC69-B-OE wheat lines. Although TaNAC69-B shares 39.83% identity (amino acid) with AtNAP, TaNAC69-B did not completely restore the delayed leaf senescence in the atnap mutant. Collectively, our results revealed a positive feedback loop, consisting of TaNAC69-B, ABA biosynthesis and leaf senescence, that is essential for the regulation of leaf senescence in wheat.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Triticum/metabolismo , Senescência Vegetal , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Folhas de Planta/metabolismo , Ácido Abscísico/metabolismo
5.
BMC Genomics ; 25(1): 232, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438880

RESUMO

BACKGROUND: The rose is one of the most important ornamental flowers in the world for its aesthetic beauty but can be attacked by many pests such as aphids. Aphid infestation causes tremendous damage on plant tissues leading to harmed petals and leaves. Rose cultivars express different levels of resistance to aphid infestation yet the information remains unclear. Not only that, studies about the transcriptional analysis on defending mechanisms against aphids in rose are limited so far. RESULTS: In this study, the aphid resistance of 20 rose cultivars was evaluated, and they could be sorted into six levels based on the number ratio of aphids. And then, a transcriptome analysis was conducted after aphid infestation in one high resistance (R, Harmonie) and one highly susceptibility (S, Carefree Wonder) rose cultivar. In open environment the majority of rose cultivars had the highest aphid number at May 6th or May 15th in 2020 and the resistance to infestation could be classified into six levels. Differential expression analysis revealed that there were 1,626 upregulated and 767 downregulated genes in the R cultivar and 481 upregulated and 63 downregulated genes in the S cultivar after aphid infestation. Pathway enrichment analysis of the differentially expressed genes revealed that upregulated genes in R and S cultivars were both enriched in defense response, biosynthesis of secondary metabolites (phenylpropanoid, alkaloid, and flavonoid), carbohydrate metabolism (galactose, starch, and sucrose metabolism) and lipid processing (alpha-linolenic acid and linolenic acid metabolism) pathways. In the jasmonic acid metabolic pathway, linoleate 13S-lipoxygenase was specifically upregulated in the R cultivar, while genes encoding other crucial enzymes, allene oxide synthase, allene oxide cyclase, and 12-oxophytodienoate reductase were upregulated in both cultivars. Transcription factor analysis and transcription factor binding search showed that WRKY transcription factors play a pivotal role during aphid infestation in the R cultivar. CONCLUSIONS: Our study indicated the potential roles of jasmonic acid metabolism and WRKY transcription factors during aphid resistance in rose, providing clues for future research.


Assuntos
Afídeos , Oxilipinas , Animais , Perfilação da Expressão Gênica , Ciclopentanos , Fatores de Transcrição
6.
BMC Genomics ; 25(1): 492, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760719

RESUMO

Rapeseed (Brassica napus L.), accounts for nearly 16% of vegetable oil, is the world's second produced oilseed. However, pod shattering has caused significant yield loses in rapeseed production, particularly during mechanical harvesting. The GH28 genes can promote pod shattering by changing the structure of the pod cell wall in Arabidopsis. However, the role of the GH28 gene family in rapeseed was largely unknown. Therefore, a genome-wide comprehensive analysis was conducted to classify the role of GH28 gene family on rapeseed pod shattering. A total of 37 BnaGH28 genes in the rapeseed genome were identified. These BnaGH28s can be divided into five groups (Group A-E), based on phylogenetic and synteny analysis. Protein property, gene structure, conserved motif, cis-acting element, and gene expression profile of BnaGH28 genes in the same group were similar. Specially, the expression level of genes in group A-D was gradually decreased, but increased in group E with the development of silique. Among eleven higher expressed genes in group E, two BnaGH28 genes (BnaA07T0199500ZS and BnaC06T0206500ZS) were significantly regulated by IAA or GA treatment. And the significant effects of BnaA07T0199500ZS variation on pod shattering resistance were also demonstrated in present study. These results could open a new window for insight into the role of BnaGH28 genes on pod shattering resistance in rapeseed.


Assuntos
Brassica napus , Filogenia , Proteínas de Plantas , Brassica napus/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Genoma de Planta , Sintenia , Perfilação da Expressão Gênica
7.
Cancer Cell Int ; 24(1): 179, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783335

RESUMO

BACKGROUND: Radiotherapy (RT) has been identified as a vital treatment for esophageal squamous cell carcinoma (ESCC), while the development of radioresistance remains a major obstacle in ESCC management. The aim of this study was to investigate the effect of NIMA-related kinase 2 (NEK2) on radioresistance in ESCC cells and to reveal potential molecular mechanisms. METHODS: Human esophageal epithelial cells (HEEC) and human ESCC cell lines were obtained from the Research Center of the Fourth Hospital of Hebei Medical University (Shijiazhuang, China). Cell Counting Kit-8 (CCK-8) and flow cytometry assays were applied to assess the proliferation ability, cell cycle, apoptosis rates, and ROS production of ESCC cells. The colony-forming assay was used to estimate the effect of NEK2 on radiosensitivity. Autophagy was investigated by western blotting analysis, GFP-mRFP-LC3 fluorescence assay, and transmission electron microscopy (TEM). RESULTS: In the present study, our results showed that NEK2 was associated with radioresistance, cell cycle arrest, apoptosis, ROS production, and survival of ESCC. NEK2 knockdown could significantly inhibit growth while enhancing radiosensitivity and ROS production in ESCC cells. Interestingly, NEK2 knockdown inhibited ESCC cell autophagy and reduced autophagic flux, ultimately reversing NEK2-induced radioresistance. Mechanistically, NEK2 bound to and regulated the stability of tripartite motif-containing protein 21 (TRIM21). The accumulation of NEK2-induced light chain 3 beta 2 (LC3B II) can be reversed by the knockdown of TRIM21. CONCLUSION: These results demonstrated that NEK2 activated autophagy through TRIM21, which may provide a promising therapeutic strategy for elucidating NEK2-mediated radioresistance in ESCC.

8.
Faraday Discuss ; 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39431431

RESUMO

Despite significant advances in nanopore nucleic acid sequencing and sensing, protein detection remains challenging due to the inherent complexity of protein molecular properties (i.e., net charges, polarity, molecular conformation & dimension) and sophisticated environmental parameters (i.e., biofluids), resulting in unsatisfactory electrical signal resolution for protein detection such as poor accessibility, selectivity and sensitivity. The selection of an appropriate electroanalytical approach is strongly desired which should be capable of offering easily detectable and readable signals regarding proteins particularly depending on the practical application. Herein, a molecular sandwich-based cooperative DNAzyme catalytic reaction nanopore detecting approach was designed. Specifically, this approach uses Mg2+ catalyzed DNAzyme (10-23) toward nucleic acids digestion for efficient antigen protein examination. The proposed strategy operates by initial formation of a molecular sandwich containing capture antibody-antigen-detection antibody for efficient entrapment of target proteins (herein taking the HIV p24 antigen for example) and immobilization on magnetic beads surfaces. After that, the DNAzyme was linked to the detection antibody via a biotin-streptavidin interaction. In the presence of Mg2+, the DNAzyme catalytic reaction was triggered to digest nucleic acid substrates and release unique cleavage fragments as reporters capable of transducing more easily detectable nucleic acids as a substitute for the complicated and hard to yield protein signals, in a nanopore. Notably, experimental validation confirms the detecting stability and sensitivity for the target antigen referenced with other antigen proteins, meanwhile it demonstrates a detection efficacy in a human serum environment at very low concentration (LoD ∼1.24 pM). This cooperative DNAzyme nanopore electroanalytical approach denotes an advance in protein examination, and may benefit in vitro testing of proteinic biomarkers for disease diagnosis and prognosis assessment.

9.
Inorg Chem ; 63(9): 4078-4085, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38390829

RESUMO

Providing efficient electronic transport channels has always been a promising strategy to mitigate the recombination of photogenerated charge carriers. In this study, a heterostructure composed of a semiconductor/photoinactive-metal-organic framework (MOF) was constructed to provide innovative channels for electronic transport. Prepared using a previously reported method ( Angew. Chem., Int. Ed. 2016, 55, 15301-15305) with slight modifications to temperature and reaction time, the CuS@HKUST-1 hollow cuboctahedron was synthesized. The CuS@HKUST-1 heterostructure possessed a well-defined cuboctahedral morphology with a uniform size of about 500 nm and a hollow structure with a thickness of around 50 nm. The CuS nanoparticles were uniformly distributed on the HKUST-1 shell. Structural characterization in cooperation with density functional theory (DFT) calculations revealed that CuS can effectively transfer photogenerated electrons to HKUST-1. CuS@HKUST-1 hollow cuboctahedrons were first introduced to the photocatalytic cycloaddition reaction of CO2 with epoxides, demonstrating excellent photocatalytic activity and stability at mild conditions (room temperature, solvent-free, and 1 atm CO2 pressure). The high photocatalytic performance of the CuS@HKUST-1 hollow cuboctahedron could be attributed to (1) the unique hollow cuboctahedron morphology, which provided a large specific surface area (693.1 m2/g) and facilitated the diffusion and transfer of reactants and products; and (2) CuS@HKUST-1 providing electronic transport channels from CuS to HKUST-1, which could enhance the adsorption and activation of CO2. Cu2+ carrying surplus electrons can activate CO2 to CO2-. The charge separation and transfer in the photocatalytic process can also be effectively promoted. This work provides a cost-effective and environmentally friendly approach for CO2 utilization reactions under ambient conditions, addressing the critical issue of rising atmospheric CO2 levels.

10.
Anal Bioanal Chem ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39419834

RESUMO

C-reactive protein (CRP) is a protein made by the liver, which is released into the bloodstream in response to inflammation. Furthermore, CRP is a potential risk factor for heart disease. Hence, it is of great importance to develop a rapid, sensitive, accurate, and cost-effective method for CRP detection. Herein, we report an enzyme-free fluorescent assay for the rapid and ultra-sensitive detection of CRP with a limit of detection (LOD) reaching as low as 3.08 pg/mL (i.e., ~ 27 fM). The high sensitivity of our method was simply achieved via dual-functionalized gold nanoparticles (AuNPs). By regulating the molar ratio of DNA to CRP antibody immobilized on the AuNP surface, hundreds to thousands-fold amplification in the analyte signal could be instantly accomplished. Furthermore, our sensor was selective: non-target proteins such as interleukin-6, interleukin-1ß, procalcitonin, bovine serum albumin, and human serum albumin did not interfere with the target CRP detection. Moreover, simulated serum samples were successfully analyzed. Given the excellent sensitivity, selectivity, and high resistance to complicated matrices, the enzyme-free CRP detection strategy developed in this work can be used as a generic platform to construct sensors for a wide variety of protein biomarkers and hence offers potential as a tool for rapid, accurate, and low-cost medical diagnosis.

11.
J Appl Microbiol ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39349994

RESUMO

AIMS: This study aimed to investigate the antibacterial and anti-inflammatory effects of the antimicrobial peptide Microcin C7 for Porphyromonas gingivalis-associated diseases. METHODS AND RESULTS: Reverse-phase high-performance liquid chromatography revealed that Microcin C7 could remain 25.5% at 12 hours in saliva. At a concentration of <10 mg mL-1, Microcin C7 showed better cytocompatibility, as revealed by hemolysis test and subchronic systemic toxicity test. Moreover, the minimum inhibitory concentration and minimum bactericidal concentration of Microcin C7 were analyzed using a broth microdilution method, bacterial growth curve, scanning electron microscopy, and confocal laser microscopy and determined to be 0.16 mg mL-1 and 5 mg mL-1, respectively. Finally, in a rat model, 5 mg mL-1 Microcin C7 showed better performance in decreasing the expression of inflammatory factors (IL-1ß, IL-6, IL-8, and TNF-α) and alveolar bone resorption than other concentrations. CONCLUSIONS: Microcin C7 demonstrated favorable biocompatibility, antibacterial activity, anti-inflammatory effect, and could decrease the alveolar bone resorption in a rat model, indicating the promising potential for clincal translation and application on P. gingivalis-associated diseases.

12.
BMC Med Imaging ; 24(1): 14, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191331

RESUMO

BACKGROUND: Accurately distinguishing between invasive thymic epithelial tumors (TETs) and anterior mediastinal lymphoma before surgery is crucial for subsequent treatment choices. But currently, the diagnosis of invasive TET is sometimes difficult to distinguish from anterior mediastinal lymphoma. OBJECTIVE: To assess the application of fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computer tomography (PET/CT) in the differential diagnosis of TETs and anterior mediastinal lymphomas. METHODS: 18F-FDG PET/CT images of 133 invasive TETs and anterior mediastinal lymphomas patients were retrospectively analyzed. In particular, the tumor's longest diameter and maximum standardized uptake value (SUVmax) were evaluated. The SUVmax and longest diameter values of the two groups were analyzed by using the receiver operating characteristic (ROC) curve to determine the optimal threshold and diagnostic efficiency. RESULTS: Age, myasthenia gravis, SUVmax and tumor longest diameter differed significantly between invasive TETs and anterior mediastinal lymphomas patients. The tumor location, calcification, relationship with adjacent vessels and distant metastasis differed significantly between the groups. The ROC analysis showed an AUC for SUVmax and tumor longest diameter of 0.841 and 0.737. Respectively, the cutoff values with the best diagnostic performance were 9.65 (sensitivity: 77.78%, specificity: 81.97%) and 6.65 (sensitivity: 80.56%, specificity: 62.30%) for SUVmax and tumor longest diameter. The diagnostic model of SUVmax, calcification, relationship with surrounding blood vessels, lymph node metastasis and lung metastasis in the highest AUC of 0.935 (sensitivity: 90.16%, specificity: 88.89%). In addition, we incorporated splenic involvement and metastatic sub-diaphragmatic lymph node into Model 2 as a new predictive model 3 for differential diagnosis and found a significant improvement in the diagnostic performance of Model 3. CONCLUSION: The diagnostic model composed of 18F-FDG PET parameters is improving the differential diagnosis of invasive TETs and anterior mediastinal lymphomas.


Assuntos
Calcinose , Linfoma , Neoplasias do Timo , Humanos , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Diagnóstico Diferencial , Estudos Retrospectivos , Neoplasias do Timo/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Computadores
13.
Ecotoxicol Environ Saf ; 279: 116468, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38776783

RESUMO

Deoxynivalenol (DON), a type B trichothecene mycotoxin, commonly occurs in cereal grains, and poses significant health risks to humans and animals. Numerous studies reveal its obvious toxic effects on male reproductive performance as well as its ability to transfer from the lactating mother to the suckling offspring through colostrum and milk. The objective of this study was to evaluate the toxic effect of lactational DON exposure on testicular morphology, hormonal levels, inflammation, apoptosis and proliferation of germ cells, tight junction, and sperm quality in male offspring. Sixty-six male offspring mice from lactating dams exposed to DON were euthanized at PND 21 and PND 70 to investigate the reproductive toxicity. Our results indicated that maternal DON exposure had a significant impact on the weight and volume of the testes, caused testicular histopathology, and reduced testosterone levels by downregulating expressions of StAR, CYP11A1, and CYP17A1 in male offspring. We also found that maternal DON exposure led to testicular inflammation in male offspring, which was attributed to increased levels of inflammatory markers, including IL-1ß, IL-6, TNF-α, and IFN-γ. Maternal DON exposure resulted in impaired tight junctions of Sertoli cells in male offspring, as evidenced by decreased expressions of ZO-1, Occludin, and Claudin-3. In addition, maternal DON exposure caused a reduction in the number of Sertoli cells and germ cells, ultimately leading to decreased sperm count and quality in adult male offspring. Collectively, these findings provide compelling evidence that maternal exposure to DON during lactation causes testicular toxicity in both pubertal and adult male offspring.


Assuntos
Lactação , Exposição Materna , Testículo , Tricotecenos , Animais , Feminino , Masculino , Testículo/efeitos dos fármacos , Testículo/patologia , Camundongos , Tricotecenos/toxicidade , Exposição Materna/efeitos adversos , Testosterona/sangue , Gravidez , Apoptose/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente
14.
Dent Traumatol ; 40(4): 435-443, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38459650

RESUMO

BACKGROUND/AIM: Results of studies investigating the association between traumatic brain injury (TBI) and maxillofacial fractures (MFs) have varied considerably. The present study aimed to evaluate the correlation between TBIs and MFs, as well as the impact of age, sex, trauma mechanism, and season on TBIs. MATERIALS AND METHODS: This 12-year retrospective study of 2841 patients used univariate and multivariate logistic regression to assess the association between MFs and other factors impacting TBIs. RESULTS: Among 2841 patients, 1978 TBIs occurred in 829 (29.2%), with intracranial injuries (n = 828) is the most common. Of 829 patients with TBIs, 688 were male and 141 were female, corresponding to a male-to-female ratio of 4.9:1.0. The most common age group was 40-49 years (24.6%). Vehicles (including motor vehicles and electric vehicles) accidents were the primary causes of injuries. Multivariate regression analyses revealed an increased risk for TBIs among males (odds ratio [OR] 0.632, p < 0.001). Patients >40 years of age were at higher risk for TBIs, especially those ≥70 years (OR 3.966, p = 0.001). Vehicle accidents were a high-risk factor for TBIs (OR 6.894, p < 0.001), and winter was the most prevalent season for such injuries (OR 1.559, p = 0.002). Risk for TBI increased by 136.4% in combined midfacial and mandibular fractures (p = 0.016) and by 101.6% in multiple midfacial fractures (p = 0.045). TBIs were less common in single mandibular fractures, notably in single-angle fractures, with a risk of only 0.204-fold. CONCLUSION: TBIs in MFs were significantly correlated with sex, age, aetiology, season and fracture location. Maxillofacial surgeons and emergency physicians must be aware of the possible association between TBIs and MFs to assess and manage this complicated relationship in a timely manner.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismos Maxilofaciais , Humanos , Masculino , Estudos Retrospectivos , Feminino , Adulto , Pessoa de Meia-Idade , Lesões Encefálicas Traumáticas/epidemiologia , Lesões Encefálicas Traumáticas/complicações , Idoso , Adolescente , Criança , Fatores de Risco , Traumatismos Maxilofaciais/epidemiologia , Pré-Escolar , Estações do Ano , Idoso de 80 Anos ou mais , Fatores Sexuais , Lactente , Fatores Etários , Fraturas Cranianas/epidemiologia , Fraturas Cranianas/complicações
15.
Dev Biol ; 487: 122-133, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525303

RESUMO

In females, the establishment of the primordial follicle pool is accompanied by a remarkable programmed oocyte loss for unclear reasons. In this study, the role of autophagy was investigated to serve as a protective mechanism for oocyte survival during chicken folliculogenesis. Inhibition of autophagy by 3-methyladenine (3-MA) led to a remarkable delay in germ cell cyst breakdown that resulted in fewer primordial follicles and retarded sequent follicular development either in vivo or in the ovarian organ culture. Furthermore, the glycolysis level was downregulated in ovaries treated with 3-MA, while Recilisib (a specific activator of Akt) reversed this inhibiting effect of 3-MA on primordial folliculogenesis. Collectively, these data indicate that autophagy functions to maintain germ cell cyst breakdown and primordial follicle assembly by regulating ovarian glycolysis involving Akt signaling in the ovaries of newly-hatched chickens.


Assuntos
Galinhas , Ovário , Animais , Autofagia/fisiologia , Galinhas/metabolismo , Feminino , Células Germinativas/metabolismo , Glicólise , Oócitos , Ovário/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
16.
J Hepatol ; 78(4): 770-782, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36708811

RESUMO

BACKGROUND & AIMS: The tumour microenvironment (TME) is a crucial mediator of cancer progression and therapeutic outcome. The TME subtype correlates with patient response to immunotherapy in multiple cancers. Most previous studies have focused on the role of different cellular components in the TME associated with immunotherapy efficacy. However, the specific structure of the TME and its role in immunotherapy efficacy remain largely unknown. METHODS: We combined spatial transcriptomics with single-cell RNA-sequencing and multiplexed immunofluorescence to identify the specific spatial structures in the TME that determine the efficacy of immunotherapy in patients with hepatocellular carcinoma (HCC) receiving anti-PD-1 treatment. RESULTS: We identified a tumour immune barrier (TIB) structure, a spatial niche composed of SPP1+ macrophages and cancer-associated fibroblasts (CAFs) located near the tumour boundary, which is associated with the efficacy of immune checkpoint blockade. Furthermore, we dissected ligand‒receptor networks among malignant cells, SPP1+ macrophages, and CAFs; that is, the hypoxic microenvironment promotes SPP1 expression, and SPP1+ macrophages interact with CAFs to stimulate extracellular matrix remodelling and promote TIB structure formation, thereby limiting immune infiltration in the tumour core. Preclinically, the blockade of SPP1 or macrophage-specific deletion of Spp1 in mice led to enhanced efficacy of anti-PD-1 treatment in mouse liver cancer, accompanied by reduced CAF infiltration and increased cytotoxic T-cell infiltration. CONCLUSIONS: We identified that the TIB structure formed by the interaction of SPP1+ macrophages and CAFs is related to immunotherapy efficacy. Therefore, disruption of the TIB structure by blocking SPP1 may be considered a relevant therapeutic approach to enhance the therapeutic effect of immune checkpoint blockade in HCC. IMPACT AND IMPLICATIONS: Only a limited number of patients with hepatocellular carcinoma (HCC) benefit from tumour immunotherapy, which significantly hinders its application. Herein, we used multiomics to identify the spatial structure of the tumour immune barrier (TIB), which is formed by the interaction of SPP1+ macrophages and cancer-associated fibroblasts in the HCC microenvironment. This structure constrains immunotherapy efficacy by limiting immune cell infiltration into malignant regions. Preclinically, we revealed that blocking SPP1 or macrophage-specific deletion of Spp1 in mice could destroy the TIB structure and sensitize HCC cells to immunotherapy. These results provide the first key steps towards finding more effective therapies for HCC and have implications for physicians, scientists, and drug developers in the field of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Microambiente Tumoral , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos
17.
Chemistry ; 29(30): e202300321, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-36890654

RESUMO

Exploring cost-efficient/durability bifunctional electrocatalysts are of upmost importance for the practical application of metal-air batteries. However, preparing bifunctional electrocatalysts with the above three advantages remains conceptually challenging. This work reports the preparation of N-doped carbon confined NiCo alloy hollow spheres (NiCo@N-C HS) as bifunctional oxygen electrocatalyst for Zn-air battery with a higher energy density (788.7 mWh gZn -1 ) and outstanding cycling stability (over 200 h), which are more durable than the commercialized Pt/C+RuO2 -based device. Electrochemical results and theoretical calculation demonstrate that the synergy in the NiCo@N-C accelerates the electronic transmission for improving activation of O2 * and OH* intermediates and optimizing reacted free energy pathways, while the hollow structures exposure more active sites for improving the reaction kinetics and enhancing the activity of ORR/OER reaction. This work provides crucial understanding for constructing low-cost transition metal-based catalyst to overcome the efficiency and durability barriers of metal-air batteries for widespread applications.

18.
Trends Analyt Chem ; 1622023 May.
Artigo em Inglês | MEDLINE | ID: mdl-38106545

RESUMO

Biomarker detection has attracted increasing interest in recent years due to the minimally or non-invasive sampling process. Single entity analysis of biomarkers is expected to provide real-time and accurate biological information for early disease diagnosis and prognosis, which is critical to the effective disease treatment and is also important in personalized medicine. As an innovative single entity analysis method, nanopore sensing is a pioneering single-molecule detection technique that is widely used in analytical bioanalytical fields. In this review, we overview the recent progress of nanopore biomarker detection as new approaches to disease diagnosis. In highlighted studies, nanopore was focusing on detecting biomarkers of different categories of communicable and noncommunicable diseases, such as pandemic Covid-19, AIDS, cancers, neurologic diseases, etc. Various sensitive and selective nanopore detecting strategies for different types of biomarkers are summarized. In addition, the challenges, opportunities, and direction for future development of nanopore-based biomarker sensors are also discussed.

19.
Cell Biol Int ; 47(3): 598-611, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36378583

RESUMO

Oxidative stress is a major cause of ovarian aging and follicular atresia. There is growing evidence that showed potential roles of rutin in antidiabetic, anti-inflammatory, antitumor, antibacterial and antioxidant, although it is yet unclear what the underlying mechanism is. Here, we looked into the potential effects of rutin on oxidative stress in the prehierarchical small white follicles (SWFs) from 580-day-old (D580) laying chickens. According to the findings, aging D580 layer ferroptosis was much higher than it was for laying hens during the peak period (280-day-old, D280). In both naturally aged and d-gal-induced chicken SWFs, rutin treatment concurrently boosted cell proliferation and prevented apoptosis. In addition, rutin inhibited the increased ferroptosis in aging hens. Meanwhile, rutin markedly suppressed the elevated ferroptosis and descending antioxidant capacity of D280-culture-SWFs from chicken elicited by d-gal. Rutin's activation of the Nrf2/HO-1 pathway hastened the SWFs' verbal battle with oxidative damage and reduced ferroptosis. Furthermore, activation of the ferroptosis signal increased the oxidative damage in SWFs. In conclusion, rutin alleviated oxidative stress that was induced by ferroptosis in aging chicken SWFs through Nrf2/HO-1 pathway. These findings point to a novel mechanism by which rutin protects SWFs from oxidative stress by suppressing ferroptosis, which is presumably a fresh approach to slowing ovarian aging in laying hens.


Assuntos
Antioxidantes , Ferroptose , Feminino , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Rutina/farmacologia , Galinhas/metabolismo , Atresia Folicular , Estresse Oxidativo , Envelhecimento
20.
Inorg Chem ; 62(16): 6518-6526, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37040307

RESUMO

Reasonable development of high-efficiency and robust electrocatalysts for efficient electrocatalytic water splitting at high current density is hopeful for renewable energy, but the real challenge is substituting the precious metal catalysts. Herein, ultrathin Fe-modified Ni2P/Ni5P4 nanosheet arrays hybridized with N-doped carbon grown on Ni foam (Fe-Ni2P/Ni5P4@N-C) were synthesized via a solvothermal-pyrolysis strategy. Theoretical calculations and in situ Raman characterizations confirm that the Fe sites can facilitate the surface reconstruction of highly active NiOOH species and significantly lower the energy barrier for the formation of the *OOH intermediate owing to the electron coupling effect between Fe and the Ni2P/Ni5P4 heterostructure. On account of the structural advantages and compositional synergy, the optimized Fe-Ni2P/Ni5P4@N-C exhibits superior hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activities with an overpotential of 105 and 280 mV to reach 10 and 50 mA cm-2, respectively, and can work stably for 60 h at 100 mA cm-2. Impressively, the electrolyzer with Fe-Ni2P/Ni5P4@N-C only needs 1.56 V to achieve 10 mA cm-2 current density for water splitting. This protocol not only provides inspiration for designing transitional metal electrocatalysts for water splitting but also puts forward a pathway for practical application.

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