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1.
J Org Chem ; 89(20): 15341-15351, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39361833

RESUMO

On the basis of the chiral ion pair between catalytic anionic stereogenic-at-cobalt(III) complexes and halonium ion intermediates, an asymmetric halogenation/semipinacol rearrangement reaction has been established using N-bromosuccinimide as the halogen source. This protocol provides an alternative approach for accessing a diverse set of chiral ß-bromocycloketones in good yields with high enantioselectivities (≤96% yield, 95.5:4.5 er).

2.
Org Lett ; 26(41): 8713-8718, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39364785

RESUMO

An intramolecular organocatalytic cascade dearomatizing spirocycloaddition reaction of indole-ynone compounds containing O-silyl-naphthol substituents has been developed with the use of a chiral bifunctional thiourea. This process was able to provide various structurally diverse polycyclic spiroindolines in high yields (up to 98%) with excellent stereoselectivities (>20:1 dr, up to 98% ee) involving the formation of carbonylvinylidene ortho-quinone methide intermediates.

3.
Cancer Res ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39288082

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal tumor with limited treatment options and poor patient survival. Circular RNAs (circRNAs) play crucial regulatory roles in the occurrence and development of various cancers, including PDAC. Here, using circRNA sequencing of diverse PDAC samples, we identified circRREB1 as an oncogenic circRNA that is significantly upregulated in PDAC and is correlated with an unfavorable patient prognosis. Functionally, loss of circRREB1 markedly inhibited glycolysis and stemness, while elevated circRREB1 elicited the opposite effects. Mechanistically, circRREB1 interacted with PGK1, disrupting the association between PTEN and PGK1 and increasing PGK1 phosphorylation to activate glycolytic flux. Moreover, circRREB1 promoted WNT7B transcription by directly interacting with YBX1 and facilitating its nuclear translocation, consequently activating the Wnt/ß-catenin signaling pathway to maintain PDAC stemness. Overall, these results highlight circRREB1 as a key regulator of metabolic and stemness properties of PDAC.

5.
Ying Yong Sheng Tai Xue Bao ; 35(6): 1716-1724, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-39235031

RESUMO

To investigate the differences on morphological growth patterns of statolith of Todarodes pacificus in the East China Sea during La Niña and normal years, we analyzed the samples of T. pacificus collected in the East China Sea by Chinese light purse seine fishery fleets from February to April in 2020 (a normal year) and 2021 (a La Niña year). The results showed that total statolith length (TSL), lateral dome length (LDL), wing length (WL), and maximum width (MW) could be used as characterization parameters to representing the morphological growth of statolith. The characterization parameters of statolith in T. pacificus differed significantly between different climate years and between different genders. The values of those characterization parameters of statolith were greater in normal year than those in La Niña year, which in both years were larger in females, except for TSL in males in La Niña year. The statolith growth of males were faster than that of females in different climate years. TSL, LDL, and WL increased faster in normal year, while MW increased faster in La Niña year. The relative size of statolith gradually slowed down with the growth of individuals.


Assuntos
Oceanos e Mares , China , Animais , Masculino , Feminino , Clima
6.
Front Cell Infect Microbiol ; 14: 1393432, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39224704

RESUMO

Introduction: The immune response regulates the severity of COVID-19 (sCOVID-19). This study examined the cause-and-effect relationship between immune cell traits (ICTs) and the risk of severe COVID-19. Additionally, we discovered the potential role of plasma metabolome in modulating this risk. Methods: Employing data from a genome-wide association study (GWAS), we conducted a two-sample Mendelian randomization (MR) assessment of 731 genetic ICTs and sCOVID-19 (5,101 cases, 1,383,241 controls) incidence. The MR analysis was utilized to further quantitate the degree of plasma metabolome-mediated regulation of immune traits in sCOVID-19. Results: The inverse variance weighted method recognized 2 plasma metabolites (PMs) responsible for casual associations between immune cells and sCOVID-19 risk. These included Tridecenedioate (C13:1-DC) which regulated the association between CD27 on IgD- CD38br (OR 0.804, 95% CI 0.699-0.925, p = 0.002) and sCOVID-19 risk (mediated proportion: 18.7%); arginine to citrulline ratio which controlled the relationship of CD39 on monocyte (OR 1.053, 95% CI 1.013-1.094, p = 0.009) with sCOVID-19 risk (mediated proportion: -7.11%). No strong evidence that genetically predicted sCOVID-19 influenced the aforementioned immune traits. Conclusion: In this study, we have successfully identified a cause-and-effect relationship between certain ICTs, PMs, and the likelihood of contracting severe COVID-19. Our findings can potentially improve the accuracy of COVID-19 prognostic evaluation and provide valuable insights into the underlying mechanisms of the disease.


Assuntos
COVID-19 , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Metaboloma , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/sangue , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Índice de Gravidade de Doença , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único
7.
ACS Nano ; 18(33): 22245-22256, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39116272

RESUMO

The spatial organization characteristics and redox status of the extracellular space (ECS) are crucial in the development of brain diseases. However, it remains a challenge to simultaneously capture dynamic changes in microstructural features and redox states at the submicron level within the ECS. Here, we developed a reversible glutathione (GSH)-responsive nanoprobe (RGN) for mapping the spatial organization features and redox status of the ECS in brain tissues with nanoscale resolution. The RGN is composed of polymer nanoparticles modified with GSH-responsive molecules and amino-functionalized methoxypoly(ethylene glycol), which exhibit exceptional single-particle brightness and excellent free diffusion capability in the ECS of brain tissues. Tracking single RGNs in acute brain slices allowed us to dynamically map spatial organizational features and redox levels within the ECS of brain tissues in disease models. This provides a powerful super-resolution imaging method that offers a potential opportunity to study the dynamic changes in the ECS microenvironment and to understand the physiological and pathological roles of the ECS in vivo.


Assuntos
Encéfalo , Espaço Extracelular , Glutationa , Nanopartículas , Oxirredução , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Animais , Espaço Extracelular/metabolismo , Espaço Extracelular/química , Glutationa/química , Glutationa/metabolismo , Nanopartículas/química , Camundongos , Polietilenoglicóis/química
8.
Adv Sci (Weinh) ; 11(34): e2309473, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38978348

RESUMO

Melatonin (N-acetyl-5-methoxytryptamine) is reported to improve mood disorders in perimenopausal women and gut microbiome composition is altered during menopausal period. The possible role of microbiome in the treatment effect of melatonin on menopausal depression remains unknown. Here, it is shown that melatonin treatment reverses the gut microbiota dysbiosis and depressive-like behaviors in ovariectomy (OVX) operated mice. This effect of melatonin is prevented by antibiotic cocktails (ABX) treatment. Transferring microbiota harvested from adolescent female mice to OVX-operated mice is sufficient to ameliorate depressive-like behaviors. Conversely, microbiota transplantation from OVX-operated mice or melatonin-treated OVX-operated mice to naïve recipient mice exhibits similar phenotypes to donors. The colonization of Alistipes Inops, which is abundant in OVX-operated mice, confers the recipient with depressive-like behaviors. Further investigation indicates that the expansion of Alistipes Inops induced by OVX leads to the degradation of intestinal tryptophan, which destroys systemic tryptophan availability. Melatonin supplementation restores systemic tryptophan metabolic disorders by suppressing the growth of Alistipes Inops, which ameliorates depressive-like behaviors. These results highlight the previously unrecognized role of Alistipes Inops in the modulation of OVX-induced behavioral disorders and suggest that the application of melatonin to inhibit Alistipes Inops may serve as a potential strategy for preventing menopausal depressive symptoms.


Assuntos
Comportamento Animal , Depressão , Modelos Animais de Doenças , Microbioma Gastrointestinal , Melatonina , Ovariectomia , Triptofano , Animais , Melatonina/farmacologia , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Triptofano/metabolismo , Triptofano/farmacologia , Feminino , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Depressão/metabolismo , Camundongos Endogâmicos C57BL , Disbiose/tratamento farmacológico
9.
World J Gastrointest Surg ; 16(6): 1609-1617, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38983327

RESUMO

BACKGROUND: Laparoscopic pancreaticoduodenectomy (LPD) is a surgical procedure for treating pancreatic cancer; however, the risk of complications remains high owing to the wide range of organs involved during the surgery and the difficulty of anastomosis. Pancreatic fistula (PF) is a major complication that not only increases the risk of postoperative infection and abdominal hemorrhage but may also cause multi-organ failure, which is a serious threat to the patient's life. This study hypothesized the risk factors for PF after LPD. AIM: To identify the risk factors for PF after laparoscopic pancreatoduodenectomy in patients with pancreatic cancer. METHODS: We retrospectively analyzed the data of 201 patients admitted to the Fudan University Shanghai Cancer Center between August 2022 and August 2023 who underwent LPD for pancreatic cancer. On the basis of the PF's incidence (grades B and C), patients were categorized into the PF (n = 15) and non-PF groups (n = 186). Differences in general data, preoperative laboratory indicators, and surgery-related factors between the two groups were compared and analyzed using multifactorial logistic regression and receiver-operating characteristic (ROC) curve analyses. RESULTS: The proportions of males, combined hypertension, soft pancreatic texture, and pancreatic duct diameter ≤ 3 mm; surgery time; body mass index (BMI); and amylase (Am) level in the drainage fluid on the first postoperative day (Am > 1069 U/L) were greater in the PF group than in the non-PF group (P < 0.05), whereas the preoperative monocyte count in the PF group was lower than that in the non-PF group (all P < 0.05). The logistic regression analysis revealed that BMI > 24.91 kg/m² [odds ratio (OR) =13.978, 95% confidence interval (CI): 1.886-103.581], hypertension (OR = 8.484, 95%CI: 1.22-58.994), soft pancreatic texture (OR = 42.015, 95%CI: 5.698-309.782), and operation time > 414 min (OR = 15.41, 95%CI: 1.63-145.674) were risk factors for the development of PF after LPD for pancreatic cancer (all P < 0.05). The areas under the ROC curve for BMI, hypertension, soft pancreatic texture, and time prediction of PF surgery were 0.655, 0.661, 0.873, and 0.758, respectively. CONCLUSION: BMI (> 24.91 kg/m²), hypertension, soft pancreatic texture, and operation time (> 414 min) are considered to be the risk factors for postoperative PF.

11.
Braz J Cardiovasc Surg ; 39(4): e20230438, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39038201

RESUMO

OBJECTIVES: The aims of the present study were to compare the long-term outcomes for ascending aortic dilatation and adverse aortic events after isolated aortic valve replacement between patients with bicuspid aortic valve (BAV) and tricuspid aortic valve ( TAV). METHODS: This retrospective study included 310 patients who had undergone isolated aortic valve replacement with an ascending aorta diameter ≤ 45 mm between January 2010 and September 2021. The patients were divided into BAV group (n=90) and TAV group (n=220). The differences in the dilation rate of the ascending aorta and long-term outcomes were analyzed. RESULTS: Overall survival was 89 ± 4% in the BAV group vs. 75 ± 6% in the TAV group at 10 years postoperatively (P=0.007), yet this difference disappeared after adjusting exclusively for age (P=0.343). The mean annual growth rate of the ascending aorta was similar between the two groups during follow-up (0.5 ± 0.6 mm/year vs. 0.4 ± 0.5 mm/year; P=0.498). Ten-year freedom from adverse aortic events was 98.1% in the BAV group vs. 95.0% in the TAV group (P=0.636). Multivariable analysis revealed preoperative ascending aorta diameter to be a significant predictor of adverse aortic events (hazard ratio: 1.76; 95% confidence interval: 1.33 to 2.38; P<0.001). CONCLUSION: Our study revealed that the long-term survival and the risks of adverse aortic events between BAV and TAV patients were similar after isolated aortic valve replacement. BAV was not a risk factor of adverse aortic events.


Assuntos
Aorta , Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Feminino , Estudos Retrospectivos , Doença da Válvula Aórtica Bicúspide/cirurgia , Doença da Válvula Aórtica Bicúspide/complicações , Pessoa de Meia-Idade , Valva Aórtica/cirurgia , Valva Aórtica/anormalidades , Idoso , Implante de Prótese de Valva Cardíaca/mortalidade , Aorta/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/mortalidade , Valva Tricúspide/cirurgia , Progressão da Doença , Fatores de Risco , Resultado do Tratamento , Complicações Pós-Operatórias
12.
Midwifery ; 135: 104052, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38875972

RESUMO

BACKGROUND: A pragmatic randomised controlled trial has confirmed the effectiveness of Urinary Incontinence for Women (UIW) app-based intervention in improving postpartum urinary incontinence (UI) severity among pregnant women. However, the causal mechanisms underlying this intervention effect remain unclear. OBJECTIVE: To examine the mediating role of self-efficacy with pelvic floor muscle training (PFMT) on the effect of the UIW app-based intervention in improving postpartum UI severity. METHODS: This was a secondary causal mediation analysis of a single-center, 2-arm, unblinded pragmatic randomised controlled trial. Singleton pregnant women without UI before pregnancy aged ≥18 years and between 24 and 28 weeks of gestation were recruited from a tertiary public hospital in China and randomised to receive the UIW app intervention plus oral PFMT instructions (n = 63) or oral PFMT instructions alone (n = 63). The primary outcome was postpartum changes in UI severity at 6 weeks. Changes in self-efficacy with PFMT 2 months after randomisation were a hypothesised mediator. Causal mediation analysis was used to estimate the average causal mediation effect (ACME), average direct effect (ADE), average total effect (ATE), and proportion mediated. A sensitivity analysis was conducted to examine the robustness of the ACME in relation to potential unmeasured confounding. RESULTS: Data from 103 participants were analyzed. The ATE of UIW app-based intervention on postpartum UI severity was 2.91 points (95 % confidence intervals [CI] 1.69 to 4.12), with ADE of 1.97 points (95 % CI 0.63 to 3.41) and the ACME 0.94 points (95 % CI 0.27 to 1.72). The proportion of ATE mediated by self-efficacy with PFMT was 0.32 (95 % CI 0.08 to 0.67). Sensitivity analysis revealed the robust ACME with respect to the potential effects of unmeasured confounding. CONCLUSION: An increase in self-efficacy with PFMT partially mediated the effect of the UIW app intervention on improvements in postpartum UI severity. TRIAL REGISTRATION: The original trial was prospectively registered in the Chinese Clinical Trial Registry under the reference number ChiCTR1800016171 on 16/05/2018. Further details can be accessed at: http://www.chictr.org.cn/showproj.aspx?proj=27455.


Assuntos
Terapia por Exercício , Análise de Mediação , Aplicativos Móveis , Diafragma da Pelve , Autoeficácia , Incontinência Urinária , Humanos , Feminino , Adulto , Gravidez , Aplicativos Móveis/normas , Incontinência Urinária/terapia , Incontinência Urinária/psicologia , Diafragma da Pelve/fisiopatologia , China , Terapia por Exercício/métodos , Terapia por Exercício/normas , Gestantes/psicologia , Período Pós-Parto
13.
Micromachines (Basel) ; 15(6)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38930769

RESUMO

The surface morphology of perovskite films significantly influences the performance of perovskite light-emitting diodes (PeLEDs). However, the thin perovskite thickness (~10 nm) results in low surface coverage on the substrate, limiting the improvement of photoelectric performance. Here, we propose a molecular additive strategy that employs pentafluorophenyl diphenylphosphinate (FDPP) molecules as additives. P=O and Pentafluorophenyl (5F) on FDPP can coordinate with Pb2+ to slow the crystallization process of perovskite and enhance surface coverage. Moreover, FDPP reduces the defect density of perovskite and enhances the crystalline quality. The maximum brightness, power efficiency (PE), and external quantum efficiency (EQE) of the optimal device reached 24,230 cd m-2, 82.73 lm W-1, and 21.06%, respectively. The device maintains an EQE of 19.79% at 1000 cd m-2 and the stability is further enhanced. This study further extends the applicability of P=O-based additives.

14.
BMC Pediatr ; 24(1): 398, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38890657

RESUMO

BACKGROUND: Autophagy is crucial for controlling the manifestation of tuberculosis. This study intends to discover autophagy-related molecular clusters as biomarkers for discriminating between latent tuberculosis (LTBI) and active tuberculosis (ATB) in children through gene expression profile analysis. METHODS: The expression of autophagy modulators was examined in pediatric patients with LTBI and ATB utilizing public datasets from the Gene Expression Omnibus (GEO) collection (GSE39939 and GSE39940). RESULTS: In a training dataset (GSE39939), patients with LTBI and ATB exhibited the expression of autophagy-related genes connected with their active immune responses. Two molecular clusters associated with autophagy were identified. Compared to Cluster 1, Cluster 2 was distinguished through decreased adaptive cellular immune response and enhanced inflammatory activation, according to single-sample gene set enrichment analysis (ssGSEA). Per the study of gene set variation, Cluster 2's differentially expressed genes (DEGs) played a role in synthesizing transfer RNA, DNA repair and recombination, and primary immunodeficiency. The peak variation efficiency, root mean square error, and area under the curve (AUC) (AUC = 0.950) were all lowered in random forest models. Finally, a seven-gene-dependent random forest profile was created utilizing the CD247, MAN1C1, FAM84B, HSZFP36, SLC16A10, DTX3, and SIRT4 genes, which performed well against the validation dataset GSE139940 (AUC = 0.888). The nomogram calibration and decision curves performed well in identifying ATB from LTBI. CONCLUSIONS: In summary, according to the present investigation, autophagy and the immunopathology of TB might be correlated. Furthermore, this investigation established a compelling prediction expression profile for measuring autophagy subtype development risks, which might be employed as possible biomarkers in children to differentiate ATB from LTBI.


Assuntos
Autofagia , Tuberculose Latente , Humanos , Tuberculose Latente/diagnóstico , Tuberculose Latente/genética , Autofagia/genética , Criança , Perfilação da Expressão Gênica , Tuberculose/genética , Tuberculose/diagnóstico , Diagnóstico Diferencial , Biomarcadores/metabolismo , Masculino , Pré-Escolar , Feminino
15.
Redox Biol ; 73: 103200, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38781729

RESUMO

Currently, chemotherapy remains occupying a pivotal place in the treatment of pancreatic ductal adenocarcinoma (PDAC). Nonetheless, the emergence of drug resistance in recent years has limited the clinical efficacy of chemotherapeutic agents, especially gemcitabine (GEM). Through bioinformatics analysis, AT-rich Interactive Domain-containing Protein 3A (ARID3A), one of transcription factors, is discovered to possibly participate in this progress. This study thoroughly investigates the potential role of ARID3A in the malignant progression and GEM chemoresistance of PDAC and explores the underlying mechanisms. The results indicate that ARID3A knockdown suppresses tumor development and enhances the sensitivity of PDAC cells to GEM in vitro and vivo. Mechanically, CUT&Tag profiling sequencing, RNA-sequencing and functional studies demonstrates that decreased ARID3A expression alleviates the transcriptional inhibition of phosphatase and tensin homolog (PTEN), consequently leading to glutathione peroxidase 4 (GPX4) depletion and increased lipid peroxidation levels. Activated ferroptosis induced by the inhibition of GPX4 subsequently restricts tumor progression and reduces GEM resistance in PDAC. This research identifies the ferroptosis regulatory pathway of ARID3A-PTEN-GPX4 axis and reveals its critical role in driving the progression and chemoresistance of pancreatic cancer. Notably, both inhibition of ARID3A and enhancement of ferroptosis can increase chemosensitivity to GEM, which offers a promising opportunity for developing therapeutic strategies to combat acquired chemotherapy resistance in pancreatic cancer.


Assuntos
Proteínas de Ligação a DNA , Resistencia a Medicamentos Antineoplásicos , Ferroptose , Regulação Neoplásica da Expressão Gênica , PTEN Fosfo-Hidrolase , Neoplasias Pancreáticas , Fatores de Transcrição , Ferroptose/efeitos dos fármacos , Ferroptose/genética , Humanos , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Camundongos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Gencitabina , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética
16.
Comput Struct Biotechnol J ; 23: 1689-1704, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38689717

RESUMO

Background: Mounting evidence underscores the importance of cell communication within the tumor microenvironment, which is pivotal in tumor proliferation, invasion, and metastasis. Exosomes play a crucial role in cell-to-cell communication. Although single-cell RNA sequencing (scRNA-seq) provides insights into individual cell transcriptional characteristics, it falls short of comprehensively capturing exosome-mediated intercellular communication. Method: We analyzed Pancreatic Ductal Adenocarcinoma (PDAC) tissues, separating supernatant and precipitate for exosome purification and single-cell nucleus suspension. We then constructed Single-nucleus RNA sequencing (snRNA-seq) and small RNA-seq libraries from these components. Our bioinformatic analysis integrated these sequences with ligand-receptor analysis and public miRNA data to map the cell communication network. Results: We established intercellular communication networks using bioinformatic analysis to track exosome miRNA effects and ligand-receptor pairs. Significantly, hsa-miR-1293 emerged as a prognostic biomarker for pancreatic cancer, linked to immune evasion, increased myeloid-derived suppressor cells, and poorer prognosis. Targeting this miRNA may enhance anti-tumor immunity and improve outcomes. Conclusion: Our study offers a novel approach to constructing intercellular communication networks using snRNA-seq and exosome-small RNA sequencing. By integrating miRNA tracing with ligand-receptor analysis, we illuminate the complex interactions in the pancreatic cancer microenvironment, highlighting the pivotal role of miRNAs and identifying potential biomarkers and therapeutic targets.

17.
Elife ; 132024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717135

RESUMO

Eukaryotic chromatin is organized into functional domains, that are characterized by distinct proteomic compositions and specific nuclear positions. In contrast to cellular organelles surrounded by lipid membranes, the composition of distinct chromatin domains is rather ill described and highly dynamic. To gain molecular insight into these domains and explore their composition, we developed an antibody-based proximity biotinylation method targeting the RNA and proteins constituents. The method that we termed antibody-mediated proximity labelling coupled to mass spectrometry (AMPL-MS) does not require the expression of fusion proteins and therefore constitutes a versatile and very sensitive method to characterize the composition of chromatin domains based on specific signature proteins or histone modifications. To demonstrate the utility of our approach we used AMPL-MS to characterize the molecular features of the chromocenter as well as the chromosome territory containing the hyperactive X chromosome in Drosophila. This analysis identified a number of known RNA-binding proteins in proximity of the hyperactive X and the centromere, supporting the accuracy of our method. In addition, it enabled us to characterize the role of RNA in the formation of these nuclear bodies. Furthermore, our method identified a new set of RNA molecules associated with the Drosophila centromere. Characterization of these novel molecules suggested the formation of R-loops in centromeres, which we validated using a novel probe for R-loops in Drosophila. Taken together, AMPL-MS improves the selectivity and specificity of proximity ligation allowing for novel discoveries of weak protein-RNA interactions in biologically diverse domains.


Assuntos
Cromatina , Espectrometria de Massas , RNA , Animais , Cromatina/metabolismo , Cromatina/química , RNA/metabolismo , RNA/química , Espectrometria de Massas/métodos , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Biotinilação , Centrômero/metabolismo , Anticorpos/metabolismo , Anticorpos/química , Cromossomo X/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/química , Coloração e Rotulagem/métodos
18.
ACS Appl Mater Interfaces ; 16(22): 28011-28028, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38783516

RESUMO

In vivo real-time qualitative and quantitative analysis is essential for the diagnosis and treatment of diseases such as tumors. Near-infrared-II (NIR-II, 1000-1700 nm) bioimaging is an emerging visualization modality based on fluorescent materials. The advantages of NIR-II region fluorescent materials in terms of reduced photon scattering and low tissue autofluorescence enable NIR-II bioimaging with high resolution and increasing depth of tissue penetration, and thus have great potential for in vivo qualitative and quantitative analysis. In this review, we first summarize recent advances in NIR-II imaging, including fluorescent probe selection, quantitative analysis strategies, and imaging. Then, we describe in detail representative applications to illustrate how NIR-II fluorescence imaging has become an important tool for in vivo quantitative analysis. Finally, we describe the future possibilities and challenges of NIR-II fluorescence imaging.


Assuntos
Corantes Fluorescentes , Imagem Óptica , Corantes Fluorescentes/química , Imagem Óptica/métodos , Humanos , Animais , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Neoplasias/diagnóstico por imagem , Raios Infravermelhos
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