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1.
Nucleic Acids Res ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38908027

RESUMO

The tripartite ParABS system mediates chromosome segregation in the majority of bacterial species. Typically, DNA-bound ParB proteins around the parS sites condense the chromosomal DNA into a higher-order multimeric nucleoprotein complex for the ParA-driven partition. Despite extensive studies, the molecular mechanism underlying the dynamic assembly of the partition complex remains unclear. Herein, we demonstrate that Bacillus subtilis ParB (Spo0J), through the multimerization of its N-terminal domain, forms phase-separated condensates along a single DNA molecule, leading to the concurrent organization of DNA into a compact structure. Specifically, in addition to the co-condensation of ParB dimers with DNA, the engagement of well-established ParB condensates with DNA allows for the compression of adjacent DNA and the looping of distant DNA. Notably, the presence of CTP promotes the formation of condensates by a low amount of ParB at parS sites, triggering two-step DNA condensation. Remarkably, parS-centered ParB-DNA co-condensate constitutes a robust nucleoprotein architecture capable of withstanding disruptive forces of tens of piconewton. Overall, our findings unveil diverse modes of DNA compaction enabled by phase-separated ParB and offer new insights into the dynamic assembly and maintenance of the bacterial partition complex.

2.
Circulation ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38328928

RESUMO

BACKGROUND: Heart failure (HF), which is the terminal stage of many cardiovascular diseases, is associated with low survival rates and a severe financial burden. The mechanisms, especially the molecular mechanism combined with new theories, underlying the pathogenesis of HF remain elusive. We demonstrate that phosphorylation-regulated dynamic liquid-liquid phase separation of HIP-55 (hematopoietic progenitor kinase 1-interacting protein of 55 kDa) protects against HF. METHODS: Fluorescence recovery after photobleaching assay, differential interference contrast analysis, pull-down assay, immunofluorescence, and immunohistochemical analysis were used to investigate the liquid-liquid phase separation capacity of HIP-55 and its dynamic regulation in vivo and in vitro. Mice with genetic deletion of HIP-55 and mice with cardiac-specific overexpression of HIP-55 were used to examine the role of HIP-55 on ß-adrenergic receptor hyperactivation-induced HF. Mutation analysis and mice with specific phospho-resistant site mutagenesis were used to identify the role of phosphorylation-regulated dynamic liquid-liquid phase separation of HIP-55 in HF. RESULTS: Genetic deletion of HIP-55 aggravated HF, whereas cardiac-specific overexpression of HIP-55 significantly alleviated HF in vivo. HIP-55 possesses a strong capacity for phase separation. Phase separation of HIP-55 is dynamically regulated by AKT-mediated phosphorylation at S269 and T291 sites, failure of which leads to impairment of HIP-55 dynamic phase separation by formation of abnormal aggregation. Prolonged sympathetic hyperactivation stress induced decreased phosphorylation of HIP-55 S269 and T291, dysregulated phase separation, and subsequent aggregate formation of HIP55. Moreover, we demonstrated the important role of dynamic phase separation of HIP-55 in inhibiting hyperactivation of the ß-adrenergic receptor-mediated P38/MAPK (mitogen-activated protein kinase) signaling pathway. A phosphorylation-deficient HIP-55 mutation, which undergoes massive phase separation and forms insoluble aggregates, loses the protective activity against HF. CONCLUSIONS: Our work reveals that the phosphorylation-regulated dynamic phase separation of HIP-55 protects against sympathetic/adrenergic system-mediated heart failure.

3.
Pharmacol Res ; 200: 107062, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211637

RESUMO

Extracellular vesicles (EVs) are tiny lipid bilayer-enclosed membrane particles released from a variety of cell types into the surrounding environment. These EVs have massive participated in cell-to-cell communication and interspecies communication. In recent years, plant-derived extracellular vesicles (PDEVs) and "exosome-like" EVs populations found in distinct plants have attracted widespread attention. Especially, research on medicinal plant-derived extracellular vesicles (MPDEVs) are increasing, which are considered a kind of promising natural compound. This review summarizes current knowledge on MPDEVs in terms of bioactive compounds, including small RNA, protein, lipid, and metabolite, have been found on the surface and/or in the lumen of MPDEVs. Moreover, both in vitro and in vivo experiments have shown that MPDEVs exert broad biomedical functions, such as anti-inflammatory, anticancer, antioxidant, modulate microbiota, etc. MPDEVs may be a better substitute than animal-derived extracellular vesicles (ADEVs) because of safety and biocompatibility in the future.


Assuntos
Exossomos , Vesículas Extracelulares , Plantas Medicinais , Animais , Vesículas Extracelulares/metabolismo , Exossomos/metabolismo , Comunicação Celular , RNA/metabolismo
4.
Epilepsy Behav ; 150: 109570, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070412

RESUMO

OBJECTIVE: Epidemiological studies have reported an association between epilepsy and dementia. However, the causal relationship between epilepsy and the risk of dementia is not clear. We aimed to inspect the causal effect of epilepsy on memory loss and dementia. METHODS: We analyzed summary data of epilepsy, memory loss, and dementia from the genome-wide association study (GWAS) using the two-sample Mendelian randomization (MR) method. We used the estimated odds ratio of memory loss and dementia associated with each of the genetically defined traits to infer evidence for a causal relationship with the following exposures: all epilepsy, focal epilepsy (including focal epilepsy with hippocampal sclerosis, lesion-negative focal epilepsy, and focal epilepsy with other lesions), and genetic generalized epilepsy (including childhood absence epilepsy, generalized tonic-clonic seizures alone, Juvenile absence epilepsy, and Juvenile myoclonic epilepsy). RESULTS: According to the result of MR using the inverse variance weighted method (IVW), we found that genetically predicted epilepsy did not causally increase the risk of memory loss and dementia (p > 0.05). Results of the MR-Egger and weighted median method were consistent with the IVW method. CONCLUSIONS: No evidence has been found to support the notion that epilepsy can result in memory loss and dementia. The associations observed in epidemiological studies could be attributed, in part, to confounding or nongenetic determinants.


Assuntos
Demência , Epilepsias Parciais , Epilepsia Tipo Ausência , Humanos , Criança , Análise da Randomização Mendeliana , Estudo de Associação Genômica Ampla , Epilepsia Tipo Ausência/complicações , Epilepsia Tipo Ausência/epidemiologia , Epilepsia Tipo Ausência/genética , Amnésia , Demência/complicações , Demência/epidemiologia , Demência/genética
5.
Mol Biol Rep ; 50(2): 1181-1190, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36435921

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies worldwide. Increasing evidence suggests that human papillomavirus (HPV) infection may be associated with the etiology of ESCC. However, the precise role of HPV in ESCC remains unclear. METHODS AND RESULTS: Proliferation and apoptosis of ESCC cells upon infection with HPV16 E6 were detected using CCK-8 assays and Western blot analyses. The migration rate was measured with a wound healing assay, and a Transwell Matrigel invasion assay was used to detect the invasive ability. RT-qPCR was performed to detect the expression of E6AP, p53, and miR-34a. The proliferation rates were significantly higher in HPV16E6-transfected cell groups compared with the negative control groups. Bax protein expression was downregulated in HPV16E6-treated groups compared to the controls. The wound healing and Transwell Matrigel invasion assays indicated that HPV16 E6 infection could increase ESCC cell migration and invasion. Furthermore, E6AP, p53 and miR-34a expression were decreased in HPV16 E6-transfected cell lines. CONCLUSION: Our results not only provide evidence that HPV16 E6 promotes cell proliferation, migration, and invasion in ESCC, but also suggests a correlation between HPV infection and E6AP, p53 and miR-34a expression. Consequently, HPV16 E6 may play an important role in ESCC development.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas do Esôfago/metabolismo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Infecções por Papillomavirus/genética , Proliferação de Células/genética , Invasividade Neoplásica , MicroRNAs/genética , Movimento Celular/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
6.
BMC Psychiatry ; 23(1): 900, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041038

RESUMO

OBJECTIVE: The doctor-patient relationship (DPR) plays a crucial role in the Chinese healthcare system, functioning to improve medical quality and reduce medical costs. This study examined the psychometric properties of the Chinese version of the Difficult Doctor-Patient Relationship Questionnaire (DDPRQ-10) among general hospital inpatients in China. METHODS: The research recruited 38 resident doctors responsible for 120 participants, and factor analyses were used to assess the construct validity of the scale. Convergent validity was evaluated by examining the correlation between DDPRQ-10 and depressive symptoms, burnout, and self-efficacy, using the Patient Health Questionnaire Depression Scale-9 item (PHQ-9), and the Maslach Burnout Inventory (MBI). Both multidimensional item response theory (MIRT) and unidimensional item response theory (IRT) frameworks were used to estimate the parameters of each item. RESULTS: The Chinese version of DDPRQ-10 showed satisfactory internal consistency (Cronbach's alpha = 0.931), and fitted in a modified two-factor model of positive feelings and negative feelings (χ2/df = 1.494, GFI = 0.925, RMSEA = 0.071, SRMR = 0.008, CFI = 0.985, NFI = 0.958, NNFI = 0.980, TLI = 0.980, IFI = 0.986). Significant correlations with PHQ-9 with DDPRQ-10 and both subscales were revealed (r = 0.293 ~ 0.333, p < .001), while DDPRQ-10 score also significantly correlated with doctors' MBI score (r = -0.467, p < .001). The MIRT model of full scale and IRT models of both subscales showed high discrimination of all items (a = 2.30 ~ 10.18), and the test information within the range of low-quality relationship was relatively high. CONCLUSION: The Chinese version of DDPRQ-10 displayed satisfactory reliability and validity and thus was appropriate for measuring the DPR in Chinese medical settings.


Assuntos
Esgotamento Profissional , Relações Médico-Paciente , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , Esgotamento Psicológico/diagnóstico
7.
Angew Chem Int Ed Engl ; 61(39): e202209463, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-35922882

RESUMO

Bloom syndrome protein (BLM) is a conserved RecQ family helicase involved in the maintenance of genome stability. BLM has been widely recognized as a genome "caretaker" that processes structured DNA. In contrast, our knowledge of how BLM behaves on single-stranded (ss) DNA is still limited. Here, we demonstrate that BLM possesses the intrinsic ability for phase separation and can co-phase separate with ssDNA to form dynamically arrested protein/ssDNA co-condensates. The introduction of ATP potentiates the capability of BLM to condense on ssDNA, which further promotes the compression of ssDNA against a resistive force of up to 60 piconewtons. Moreover, BLM is also capable of condensing replication protein A (RPA)- or RAD51-coated ssDNA, before which it generates naked ssDNA by dismantling these ssDNA-binding proteins. Overall, our findings identify an unexpected characteristic of a DNA helicase and provide a new angle of protein/ssDNA co-condensation for understanding the genomic instability caused by BLM overexpression under diseased conditions.


Assuntos
Síndrome de Bloom , RecQ Helicases/metabolismo , Trifosfato de Adenosina/metabolismo , Síndrome de Bloom/genética , DNA , Reparo do DNA , DNA de Cadeia Simples , Instabilidade Genômica , Humanos , RecQ Helicases/genética , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo
8.
Analyst ; 144(2): 512-520, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30489587

RESUMO

Native mass spectrometry has been recognized as a powerful tool for probing interactions between small molecules, such as drugs and natural products, and target proteins. However, the presence of heterogeneous proteins and metabolites in real biological systems can alter the conformations of target proteins or compete with candidate ligands, thus necessitating a method for measuring binding stoichiometries in matrices aside from the extensively used pure/recombinant protein systems. Furthermore, some small molecule-protein interactions have a transient and low-affinity nature and thus can be mis-assigned as nonspecific binding complexes that are often formed during the native ESI process. A native-denatured exchange (NDX) approach was recently developed using a reactive desorption electrospray ionization-mass spectrometer (DESI-MS) setup to screen specific interacting partners. The method works by gradually increasing the composition of denaturing solvents contained in the DESI spray and thus conferring a switch from a native to denatured ionization environment. This change impairs three-dimensional structures of target proteins and disrupts specific ligand-protein interactions, leading to decreased holo/apo ratios. In contrast, ligand-protein complexes exhibiting different trends are assigned as nonspecific interactions. Herein, we applied the NDX approach to probe specific ligand-protein interactions in biological matrices. We first used mixtures of model ligands and proteins to examine the use of reactive DESI-MS in recognizing ligand-target binding in mixtures. Subsequently, we used the NDX approach to analyze binding affinity curves of ligands to target proteins spiked in cell lysates with the aid of size exclusion chromatography and demonstrated its use in probing specific ligand-protein interactions from cell matrices.


Assuntos
Ligantes , Proteínas/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia em Gel , Medição da Troca de Deutério , Células HCT116 , Humanos , Muramidase/química , Muramidase/metabolismo , Nucleotídeos/química , Nucleotídeos/metabolismo , Ligação Proteica , Proteínas/química , Ribonuclease Pancreático/química , Ribonuclease Pancreático/metabolismo
9.
Cell Physiol Biochem ; 49(1): 322-334, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30138934

RESUMO

BACKGROUND/AIMS: LncRNA EGFR-AS1 is an antisense transcript of EGFR, which plays a key role in gastric cancer progression. This study was aimed to explore the effects of lncRNA EGFR-AS1 on GC and the underling mechanisms. METHODS: The silencing of EGFR-AS1 expression was performed by using EGFR-AS1 shRNA lentivirus in MGC803 and SGC-7901 GC cell. The levels of lncRNA EGFR-AS1 and EGFR were detected by qPCR and western blot. Cell proliferation was assessed by CCK-8, EdU, and colony formation assays. The EGFR mRNA stability was explored by using RNA synthesis inhibitor α-amanitin. RESULTS: In our study, EGFR-AS1 significantly up-regulated in GC tissues and correlated with tumor size. And the expression of EGFR-AS1 positively correlated with EGFR in tissues. Moreover, knock-down of EGFR-AS1 inhibited the proliferation of GC cells via suppressing EGFR-dependent PI3K/AKT pathway in vitro and in vivo. Mechanismly, depletion of EGFR-AS1 was found to decrease EGFR expression by reduction of EGFR mRNA stability. CONCLUSION: Our findings suggested that EGFR-AS1 might have an oncogenic effect on GC and serve as a potential target of GC.


Assuntos
Receptores ErbB/metabolismo , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Neoplasias Gástricas/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Receptores ErbB/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Estabilidade de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Neoplasias Gástricas/metabolismo
10.
Tumour Biol ; 37(1): 877-85, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26254611

RESUMO

Aberrant DNA methylation of CpG site is among the earliest and most frequent alterations in developmental process and diseases including cancer. To elucidate the functional preferred site of DNMTs, we analyzed the feature of distinct methylated sequences and established the defined relationship between DNMTs and preference genomic DNA sequences. Small interfering RNA (siRNA) construct of DNTM1, DNMT3A, and DNMT3B was transfected into the human hepatocellular carcinoma cell line SMMC-7721, respectively. Distinguishing methylated fragments pool was enriched by SHH method in cells which is knocked down DNMT1, DNMT3A, DNMT3B, separately. The defined binding transcription factors (TFs) containing of 5'CpG islands were obtained with bioinformatics software and website. In SMMC-7721 hepatocellular carcinoma (HCC) cell line, DNMT1, DNMT3A, and DNMT3B were specific suppressed by their corresponding siRNA construct, separately. A 46, 42, 67 distinctive methylated fragments from three different DNMTs were evaluated according to genomic DNA database. Those separated fragments were distributed among genomic DNA regions of all chromosome complements, including coding genes, repeat sequences, and genes with unknown function. The majority of coding genes contain CpG islands in their promoter region. Cluster analysis demonstrated all of preference sequences identified by three DNMTs shares their own conserved sequences. In depleting of different DNMTs cells, 80 % of 103 upregulation genes induced by DNMT1 knock-down contain CpG sites; 76 % of 25 upregulation genes induced by DNMT3A knock-down contain CpG sites; 63 % of 126 upregulation genes induced by DNMT3B knock-down contain CpG sites. Our findings suggested that distinctive DNMTs targeted DNA methylation site to their preference sequences, and this targeting might be associated with diverse roles of DNMTs in tumorigenesis. Meanwhile, the analysis of preference sequences provides an alternative way to find out the individual function of DNMTs.


Assuntos
Carcinoma Hepatocelular/genética , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Análise por Conglomerados , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferase 1 , DNA Metiltransferase 3A , Epigênese Genética , Perfilação da Expressão Gênica , Humanos , Neoplasias Hepáticas/metabolismo , Hibridização de Ácido Nucleico , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Regulação para Cima , DNA Metiltransferase 3B
11.
World J Surg Oncol ; 13: 101, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25889078

RESUMO

BACKGROUND: MicroRNAs (miRNAs) play an important role in a tumor-suppressive or oncogenic manner in carcinogenesis. Alteration expression patterns of miRNAs in gastric cancer (GC) are associated with cancer initiation and progression. In the present study, we evaluated miR-29a-3p expression pattern and its function in gastric carcinogenesis. METHODS: The expression of miR-29a-3p in GC tissue samples and cell lines was detected by quantitative real-time PCR (qRT-PCR). After transfected with miR-29a-3p mimics or inhibitor, the cell proliferation, cell migration, and invasion ability were assessed by CCK-8 assay, wound healing assay, and Trans-well assay, respectively. The level of CDK2, CDK4, CDK6, and CyclinD1 were determined by qRT-PCR and Western blot. RESULTS: Compared with the corresponding non-tumor tissues, miR-29a-3p showed a significant down-regulated expression in tumor tissues. In vitro functional assays demonstrated that enforced miR-29a-3p expression inhibited cell proliferation by reducing the expression of CDK2, CDK4, and CDK6. Wound healing and Transwell assays revealed that miR-29a-3p suppressed tumor metastasis in GC. CONCLUSIONS: Our preliminary results suggest that altered expression of miR-29a-3p is involved in gastric cancer process. The present study provides the first insight into the specific role of miR-29a-3p in gastric carcinogenesis.


Assuntos
Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Apoptose , Western Blotting , Regulação para Baixo , Humanos , Invasividade Neoplásica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
12.
Mol Biol Rep ; 41(9): 5693-700, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24913034

RESUMO

miRNAs have emerged as crucial regulators in the regulation of development as well as human diseases, especially tumorigenesis. The aims of this study are to evaluate miR-30b-5p expression pattern and mechanism in gastric carcinogenesis due to which remains to be determined. Expression of miR-30b-5p was analyzed in 51 gastric cancer cases and 4 cell lines by qRT-PCR. The effect of DNA methylation on miR-30b-5p expression was assessed by MSP and BGS. In order to know whether DNMT1 increased miR-30b-5p promoter methylation, DNMT1 was depleted in cell lines AGS and BGC-823. The role of miR-30b-5p on cell migration was evaluated by wound healing assays. Decreased expression of miR-30b-5p was found in gastric cancer samples. In tumor, the expression level of miR-30b-5p was profound correlated with lymph node metastasis (P = 0.019). The level of miR-30b-5p may be restored by DNA demethylation and DNMT1 induced miR-30b-5p promoter methylation. In vitro functional assays implied that enforced miR-30b-5p expression affected cell migration, consistent with tissues analysis. Our findings uncovered that miR-30b-5p is significantly diminished in gastric cancer tissues, providing the first insight into the epigenetic mechanism of miR-30b-5p down-regulation, induced by DNMT1, and the role of miR-30b-5p in gastric cancer carcinogenesis. Overexpression of miR-30b-5p inhibited cell migration. Thus, miR-30b-5p may represent a potential therapeutic target for gastric cancer therapy.


Assuntos
DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Gástricas/genética , Linhagem Celular Tumoral , Movimento Celular , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/genética , Regulação para Baixo , Deleção de Genes , Humanos , Metástase Linfática , MicroRNAs/genética , Regiões Promotoras Genéticas
13.
Nat Commun ; 15(1): 2147, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459060

RESUMO

The burgeoning comprehension of protein phase separation (PS) has ushered in a wealth of bioinformatics tools for the prediction of phase-separating proteins (PSPs). These tools often skew towards PSPs with a high content of intrinsically disordered regions (IDRs), thus frequently undervaluing potential PSPs without IDRs. Nonetheless, PS is not only steered by IDRs but also by the structured modular domains and interactions that aren't necessarily reflected in amino acid sequences. In this work, we introduce PSPire, a machine learning predictor that incorporates both residue-level and structure-level features for the precise prediction of PSPs. Compared to current PSP predictors, PSPire shows a notable improvement in identifying PSPs without IDRs, which underscores the crucial role of non-IDR, structure-based characteristics in multivalent interactions throughout the PS process. Additionally, our biological validation experiments substantiate the predictive capacity of PSPire, with 9 out of 11 chosen candidate PSPs confirmed to form condensates within cells.


Assuntos
Proteínas Intrinsicamente Desordenadas , Proteínas Intrinsicamente Desordenadas/metabolismo , Sequência de Aminoácidos
14.
PeerJ ; 12: e17677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974410

RESUMO

Background: The study aims to evaluate the diagnostic efficacy of contrast-enhanced ultrasound (CEUS) and shear-wave elastography (SWE) in detecting small malignant breast nodules in an effort to inform further refinements of the Breast Imaging Reporting and Data System (BI-RADS) classification system. Methods: This study retrospectively analyzed patients with breast nodules who underwent conventional ultrasound, CEUS, and SWE at Gongli Hospital from November 2015 to December 2019. The inclusion criteria were nodules ≤ 2 cm in diameter with pathological outcomes determined by biopsy, no prior treatments, and solid or predominantly solid nodules. The exclusion criteria included pregnancy or lactation and low-quality images. Imaging features were detailed and classified per BI-RADS. Diagnostic accuracy was assessed using receiver operating characteristic curves. Results: The study included 302 patients with 305 breast nodules, 113 of which were malignant. The diagnostic accuracy was significantly improved by combining the BI-RADS classification with CEUS and SWE. The combined approach yielded a sensitivity of 88.5%, specificity of 87.0%, positive predictive value of 80.0%, negative predictive value of 92.8%, and accuracy of 87.5% with an area under the curve of 0.877. Notably, 55.8% of BI-RADS 4A nodules were downgraded to BI-RADS 3 and confirmed as benign after pathological examination, suggesting the potential to avoid unnecessary biopsies. Conclusion: The integrated use of the BI-RADS classification, CEUS, and SWE enhances the accuracy of differentiating benign and malignant small breast nodule, potentially reducing the need for unnecessary biopsies.


Assuntos
Neoplasias da Mama , Meios de Contraste , Técnicas de Imagem por Elasticidade , Ultrassonografia Mamária , Humanos , Feminino , Técnicas de Imagem por Elasticidade/métodos , Estudos Retrospectivos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Pessoa de Meia-Idade , Adulto , Ultrassonografia Mamária/métodos , Idoso , Sensibilidade e Especificidade , Curva ROC , Mama/diagnóstico por imagem , Mama/patologia
15.
Chem Sci ; 15(27): 10508-10518, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38994413

RESUMO

Hsp90α, a pivotal canonical chaperone, is renowned for its broad interaction with numerous protein clients to maintain protein homeostasis, chromatin remodeling, and cell growth. Recent studies indicate its role in modifying various components of membraneless organelles (MLOs) such as stress granules and processing bodies, suggesting its participation in the regulation of protein condensates. In this study, we found that Hsp90α possesses an inherent ability to form dynamic condensates in vitro. Utilizing LC-MS/MS, we further pinpointed proteins in cell lysates that preferentially integrate into Hsp90α condensates. Significantly, we observed a prevalence of RG motif repeats in client proteins of Hsp90α condensates, many of which are linked to various MLOs. Moreover, each of the three domains of Hsp90α was found to undergo phase separation, with numerous solvent-exposed negatively charged residues on these domains being crucial for driving Hsp90α condensation through multivalent weak electrostatic interactions. Additionally, various clients like TDP-43 and hnRNPA1, along with poly-GR and PR dipeptide repeats, exhibit varied impacts on the dynamic behavior of Hsp90α condensates. Our study spotlights various client proteins associated with Hsp90α condensates, illustrating its intricate adaptive nature in interacting with diverse clients and its functional adaptability across multiple MLOs.

16.
Nat Cell Biol ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951706

RESUMO

α-Synuclein (α-Syn) aggregation is closely associated with Parkinson's disease neuropathology. Physiologically, α-Syn promotes synaptic vesicle (SV) clustering and soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex assembly. However, the underlying structural and molecular mechanisms are uncertain and it is not known whether this function affects the pathological aggregation of α-Syn. Here we show that the juxtamembrane region of vesicle-associated membrane protein 2 (VAMP2)-a component of the SNARE complex that resides on SVs-directly interacts with the carboxy-terminal region of α-Syn through charged residues to regulate α-Syn's function in clustering SVs and promoting SNARE complex assembly by inducing a multi-component condensed phase of SVs, α-Syn and other components. Moreover, VAMP2 binding protects α-Syn against forming aggregation-prone oligomers and fibrils in these condensates. Our results suggest a molecular mechanism that maintains α-Syn's function and prevents its pathological amyloid aggregation, the failure of which may lead to Parkinson's disease.

17.
Nat Commun ; 14(1): 5717, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37714826

RESUMO

Despite the extremely high hardness of recently proposed high-entropy carbides (HECs), the low fracture toughness limits their applications in harsh mechanical environment. Here, we introduce a metastability engineering strategy to achieve superhard HECs with enhanced toughness via in-situ metastable particles. This is realized by developing a (WTaNbZrTi)C HEC showing a solid solution matrix with uniformly dispersed in-situ tetragonal and monoclinic ZrO2 particles. Apart from a high hardness of 21.0 GPa, the HEC can obtain an enhanced fracture toughness of 5.89 MPa·m1/2, significantly exceeding the value predicted by rule of mixture and that of other reported HECs. The toughening effect is primarily attributed to the transformation of the metastable tetragonal ZrO2 particles under mechanical loading, which promotes crack tip shielding mechanisms including crack deflection, crack bridging and crack branching. The work demonstrates the concept of using in-situ metastable particles for toughening bulk high-entropy ceramics by taking advantage of their compositional flexibility.

18.
Front Psychiatry ; 14: 1138361, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36993920

RESUMO

Background: Frontline healthcare workers (FHWs) experienced psychological stress and heavy workload during COVID-19 pandemic. This study examined the psychological symptoms and occupational burnout of FHWs in a fever clinic during different periods of the pandemic. Methods: A cross-sectional survey of FHWs in the fever clinic of a tertiary hospital was carried out during both the outbreak period and regular period of COVID-19. Psychological measurement instruments including Generalized Anxiety Disorder 7-item, the 9-Question Patient Health Questionnaire, the Maslach Burnout Inventory-Human Service Survey, and the General Self-Efficacy Scale were used to evaluate anxiety, depression, burnout, and self-efficacy, respectively. The correlation between clinical variables was explored. Results: A total of 162 participants were involved in this study, including 118 FHWs during the outbreak period (Group 1) and 44 FHWs during the regular period (Group 2). Anxiety symptoms were more prevalent in Group 2 (x 2 = 27.477) while depressive symptoms were significantly more prevalent in Group 1 (x 2 = 69.538). Burnout rate was higher in Group 2 (x 2 = 29.526). Self-efficacy was higher in Group 1 (t = 3.194). Burnout was positively correlated with anxiety symptoms (r 2 = 0.424) and negatively correlated with self-efficacy (r 2 = -0.312). Conclusion: Anxiety, depressive symptoms and burnout were prevalent in FHWs during different periods of the COVID-19 pandemic. There is a tendency to be less depressed, but more anxious and burned out over time, although the severity of the pandemic is decreasing. Self-efficacy may be an important factor in protecting FHWs from occupational burnout. Support and intervention plans for FHWs should be made at the institutional level.

19.
Front Psychiatry ; 14: 1117174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36873225

RESUMO

Objective: The patient-doctor relationship has been considered as a crucial concept in primary healthcare, while the medical reform launched by the Chinese government in 2009 has brought significant changes to the healthcare system, which made it urgent to introduce reliable measurement instruments for assessing today's doctor-patient relationship in China. This study examined the psychometric properties of the Chinese version of the Patient-Doctor-Relationship Questionnaire-9 item (PDRQ-9) scale among general hospital inpatients in China. Materials and methods: A total of 203 participants responded to the survey, of which 39 completed retest after 7 days. Factor analyses were used to test the construct validity of the scale. Convergent validity was evaluated by the correlation between PDRQ-9 and depressive symptoms measured using PHQ-9 (Patient Health Questionnaire Depression Scale-9 item). Both multidimensional item response theory (MIRT) and unidimensional item response theory (IRT) framework were used to estimate the parameters of each item. Results: The two-factor model of relationship quality and treatment quality was supported (χ2/df = 1.494, GFI = 0.925, RMSEA = 0.071, RMR = 0.008, CFI = 0.985, NFI = 0.958, NNFI = 0.980, TLI = 0.980, IFI = 0.986). The PDRQ-9 and both subscales showed significant correlation with PHQ-9 (r = -0.196∼-0.309) and good internal consistency (Cronbach's alpha = 0.865∼0.933). ANCOVA analysis adjusted with age revealed significant difference in PDRQ-9 ratings between patients with or without significant depressive symptoms (P = 0.019). The 7-day test-retest reliability of the scale was 0.730. The MIRT model of full scale and IRT models of both subscales showed high discrimination of all items (a = 2.46∼38.46), and the test information within the range of low-quality relationship was relatively high. Conclusion: The Chinese version of PDRQ-9 is a valid and reliable rating scale, which can measure the doctor-patient relationship among Chinese patients.

20.
J Psychiatr Res ; 164: 66-71, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37327502

RESUMO

OBJECTIVE: To identify susceptible biomarkers for the development of bipolar disorder (BD), we conducted a Mendelian Randomization (MR) design to screen circulating proteins for the potential risk of bipolar disorder systematically. METHODS: We performed a two-sample Mendelian randomization (MR) analysis to estimate the causality of 4782 human circulating proteins on the risk of bipolar disorder. 376 circulating biomarkers were selected in MR estimation (4406 circulating proteins with less than 3 SNPs were excluded) with 5368 European descents. GWAS meta-analysis of the potential role of all-cause bipolar disorder arose from the Psychiatric Genomics Consortium (41,917 cases, 371,549 controls). RESULTS: After IVW and sensitivity analysis, 4 circulating proteins having causal effects on bipolar disorder were identified. ISG15, as a key player in the innate immune response, decreased the risk of bipolar disorder causally (OR = 0.92, 95% CI = 0.89-0.94, P = 1.46e-09). Furthermore, MLN decreased the risk of bipolar disorder causally (OR = 0.94, 95% CI = 0.91-0.97, P = 1.04e-04). In addition, SFTPC (OR = 0.91, 95% CI = 0.86-0.96, P = 4.47e-04) and VCY (OR = 0.86, 95% CI = 0.77-0.96, P = 8.55e-03) presented a suggestive association with bipolar disorder. CONCLUSIONS: Our findings indicated that ISG15 and MLN showed evidence of causality in bipolar disorder and provided a promising target for the diagnosis and treatment of diseases.


Assuntos
Transtorno Bipolar , Humanos , Transtorno Bipolar/genética , Análise da Randomização Mendeliana , Imunidade Inata , Polimorfismo de Nucleotídeo Único/genética , Estudo de Associação Genômica Ampla
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