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1.
IEEE Trans Cybern ; PP2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39024069

RESUMEN

In this article, the stability analysis for generalized neural networks (GNNs) with a time-varying delay is investigated. About the delay, the differential has only an upper boundary or cannot be obtained. For the both two types of delayed GNNs, up to now, the second-order integral inequalities have been the highest-order integral inequalities utilized to derive the stability conditions. To establish the stability conditions on the basis of the high-order integral inequalities, two challenging issues are required to be resolved. One is the formulation of the Lyapunov-Krasovskii functional (LKF), the other is the high-degree polynomial negative conditions (NCs). By transforming the integrals in N -order generalized free-matrix-based integral inequalities (GFIIs) into the multiple integrals, the hierarchical LKFs are constructed by adopting these multiple integrals. Then, the novel modified matrix polynomial NCs are presented for the 2N-1 degree delay polynomials in the LKF differentials. Thus, the hierarchical linear matrix inequalities (LMIs) are set up and the nonlinear problems caused by the GFIIs are solved at the same time. Eventually, the superiority of the provided hierarchical stability criteria is demonstrated by several numeric examples.

2.
ACS Omega ; 9(28): 30404-30414, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39035965

RESUMEN

The urgent need for sustainable and efficient energy conversion technologies has propelled research into novel electrocatalysts for fuel cell applications. This study investigates a carbon paper (CP)-supported Ni2O3 catalyst for the electrocatalytic oxidation of ethanol. We utilized electrodeposition to uniformly deposit/dop Ni2O3 onto the CP, creating an effective electrocatalyst. Our approach allows the tailoring of the doping degree by adjusting the electrodeposition potential. The optimal doping degree, achieved at a medium deposition potential, results in an electrode with high intrinsic activity and a substantial electrochemically active surface area (ECSA), thereby enhancing its electrocatalytic activity. This catalyst efficiently facilitates the oxidation of ethanol to formic acid while maintaining good stability. The enhanced performance is attributed to the effective interface and interaction between Ni2O3 and CP. This work not only provides insights into the design of efficient Ni-based catalysts for ethanol oxidation but also paves the way for developing advanced materials for renewable energy conversion.

3.
Adv Mater ; : e2407923, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39081109

RESUMEN

Solid-state lithium-ion batteries (SSLIBs) have been considered as the priority candidate for next-generation energy storage system, due to their advantages in safety and energy density compare with conventional liquid electrolyte systems. However, the introduction of numerous solid-solid interfaces results in a series of issues, hindering the further development of SSLIBs. Therefore, a thorough understanding on the interfacial issues is essential to promote the practical applications for SSLIBs. In this review, the interface issues are discussed from the perspective of transportation mechanism of electrons and lithium ions, including internal interfaces within cathode/anode composites and solid electrolytes (SEs), as well as the apparent electrode/SEs interfaces. The corresponding interface modification strategies, such as passivation layer design, conductive binders, and thermal sintering methods, are comprehensively summarized. Through establishing the correlation between carrier transport network and corresponding battery electrochemical performance, the design principles for achieving a selective carrier transport network are systematically elucidated. Additionally, the future challenges are speculated and research directions in tailoring interfacial structure for SSLIBs. By providing the insightful review and outlook on interfacial charge transfer, the industrialization of SSLIBs are aimed to promoted.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38875088

RESUMEN

Few-shot object detection (FSOD) identifies objects from extremely few annotated samples. Most existing FSOD methods, recently, apply the two-stage learning paradigm, which transfers the knowledge learned from abundant base classes to assist the few-shot detectors by learning the global features. However, such existing FSOD approaches seldom consider the localization of objects from local to global. Limited by the scarce training data in FSOD, the training samples of novel classes typically capture part of objects, resulting in such FSOD methods being unable to detect the completely unseen object during testing. To tackle this problem, we propose an Extensible Co-Existing Attention (ECEA) module to enable the model to infer the global object according to the local parts. Specifically, we first devise an extensible attention mechanism that starts with a local region and extends attention to co-existing regions that are similar and adjacent to the given local region. We then implement the extensible attention mechanism in different feature scales to progressively discover the full object in various receptive fields. In the training process, the model learns the extensible ability on the base stage with abundant samples and transfers it to the novel stage of continuous extensible learning, which can assist the few-shot model to quickly adapt in extending local regions to co-existing regions. Extensive experiments on the PASCAL VOC and COCO datasets show that our ECEA module can assist the few-shot detector to completely predict the object despite some regions failing to appear in the training samples and achieve the new state-of-the-art compared with existing FSOD methods. Code is released at https://github.com/zhimengXin/ECEA.

6.
bioRxiv ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38559186

RESUMEN

Paired-class homeodomain transcription factors (HD TFs) play essential roles in vertebrate development, and their mutations are linked to human diseases. One unique feature of paired-class HD is cooperative dimerization on specific palindrome DNA sequences. Yet, the functional significance of HD cooperative dimerization in animal development and its dysregulation in diseases remain elusive. Using the retinal TF Cone-rod Homeobox (CRX) as a model, we have studied how blindness-causing mutations in the paired HD, p.E80A and p.K88N, alter CRX's cooperative dimerization, lead to gene misexpression and photoreceptor developmental deficits in dominant manners. CRXE80A maintains binding at monomeric WT CRX motifs but is deficient in cooperative binding at dimeric motifs. CRXE80A's cooperativity defect impacts the exponential increase of photoreceptor gene expression in terminal differentiation and produces immature, non-functional photoreceptors in the CrxE80A retinas. CRXK88N is highly cooperative and localizes to ectopic genomic sites with strong enrichment of dimeric HD motifs. CRXK88N's altered biochemical properties disrupt CRX's ability to direct dynamic chromatin remodeling during development to activate photoreceptor differentiation programs and silence progenitor programs. Our study here provides in vitro and in vivo molecular evidence that paired-class HD cooperative dimerization regulates neuronal development and dysregulation of cooperative binding contributes to severe dominant blinding retinopathies.

7.
Cell Death Dis ; 15(4): 288, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654006

RESUMEN

Cancer stem cells (CSCs) are believed to be responsible for cancer metastasis and recurrence due to their self-renewal ability and resistance to treatment. However, the mechanisms that regulate the stemness of CSCs remain poorly understood. Recently, evidence has emerged suggesting that long non-coding RNAs (lncRNAs) play a crucial role in regulating cancer cell function in different types of malignancies, including gastric cancer (GC). However, the specific means by which lncRNAs regulate the function of gastric cancer stem cells (GCSCs) are yet to be fully understood. In this study, we investigated a lncRNA known as HNF1A-AS1, which is highly expressed in GCSC s and serves as a critical regulator of GCSC stemness and tumorigenesis. Our experiments, both in vitro and in vivo, demonstrated that HNF1A-AS1 maintained the stemness of GC cells. Further analysis revealed that HNF1A-AS1, transcriptionally activated by CMYC, functioned as a competing endogenous RNA by binding to miR-150-5p to upregulate ß-catenin expression. This in turn facilitated the entry of ß-catenin into the nucleus to activate the Wnt/ß-catenin pathway and promote CMYC expression, thereby forming a positive feedback loop that sustained the stemness of GCSCs. We also found that blocking the Wnt/ß-catenin pathway effectively inhibited the function of HNF1A-AS1, ultimately resulting in the inhibition of GCSC stemness. Taken together, our results demonstrated that HNF1A-AS1 is a regulator of the stemness of GCSCs and could serve as a potential marker for targeted GC therapy.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Células Madre Neoplásicas , ARN Largo no Codificante , Neoplasias Gástricas , Animales , Humanos , Ratones , beta Catenina/metabolismo , Línea Celular Tumoral , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Factor Nuclear 1-alfa del Hepatocito/genética , Ratones Endogámicos BALB C , Ratones Desnudos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Neoplasias Gástricas/patología , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Vía de Señalización Wnt/genética
8.
Hematology ; 29(1): 2331389, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38511642

RESUMEN

OBJECTIVE: Plant homeodomain finger protein 19 (PHF19) regulates hematopoietic stem cell differentiation and promotes multiple myeloma (MM) progression. This study intended to explore the potency of PHF19 at baseline and post induction treatment in estimating treatment response to protease inhibitors and survival in MM patients. METHODS: This retrospective study screened 69 MM patients who received protease inhibitors with bone marrow (BM) samples available at both baseline and post induction treatment. Twenty healthy BM donors were included as healthy controls (HCs). PHF19 in plasma cells from BM was quantified by reverse transcription-quantitative polymerase chain reaction. RESULTS: PHF19 at baseline and post induction treatment in MM patients were increased than in HCs. In MM patients, PHF19 was declined post induction treatment. Elevated PHF19 at baseline and post induction treatment were correlated with renal impairment, beta-2-microglobulin ≥5.5 mg/L, t (4; 14), higher international staging system (ISS) stage, and higher revised ISS (R-ISS) stage. Concerning treatment response, PHF19 at baseline and post induction treatment were negatively associated with complete response and overall response rate. Notably, abnormal PHF19 (above 95% quantile value of PHF19 in HCs) at baseline and post induction treatment were linked with shortened event-free survival (EFS) and overall survival (OS). After adjustment, abnormal PHF19 post induction treatment was independently related to shortened EFS (hazard ratio = 2.474) and OS (hazard ratio = 3.124). CONCLUSION: PHF19 is aberrantly high and declines post induction therapy, which simultaneously reflects unfavorable treatment response to protease inhibitors as well as shorter EFS and OS in MM patients.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple , Humanos , Supervivencia sin Progresión , Estudios Retrospectivos , Inhibidores de Proteasas , Pronóstico , Proteínas de Unión al ADN , Factores de Transcripción
9.
ACS Nano ; 18(8): 6600-6611, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38353590

RESUMEN

Coupling Ni-rich layered oxide cathodes with Si-based anodes is one of the most promising strategies to realize high-energy-density Li-ion batteries. However, unstable interfaces on both cathode and anode sides cause continuous parasitic reactions, resulting in structural degradation and capacity fading of full cells. Herein, lithium tetrafluoro(oxalato) phosphate is synthesized and applied as a multifunctional electrolyte additive to mitigate irreversible volume swing of the SiOx anode and suppress undesirable interfacial evolution of the LiNi0.83Co0.12Mn0.05O2 (NCM) cathode simultaneously, resulting in improved cycle life. Benefiting from its desirable redox thermodynamics and kinetics, the molecularly tailored additive facilitates matching interphases consisting of LiF, Li3PO4, and P-containing macromolecular polymer on both the NCM cathode and SiOx anode, respectively, modulating interfacial chemo-mechanical stability as well as charge transfer kinetics. More encouragingly, the proposed strategy enables 4.4 V 21700 cylindrical batteries (5 Ah) with excellent cycling stability (92.9% capacity retention after 300 cycles) under practical conditions. The key finding points out a fresh perspective on interfacial optimization for high-energy-density battery systems.

10.
Front Cell Neurosci ; 18: 1347436, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38414750

RESUMEN

The vertebrate retina is made up of six specialized neuronal cell types and one glia that are generated from a common retinal progenitor. The development of these distinct cell types is programmed by transcription factors that regulate the expression of specific genes essential for cell fate specification and differentiation. Because of the complex nature of transcriptional regulation, understanding transcription factor functions in development and disease is challenging. Research on the Cone-rod homeobox transcription factor CRX provides an excellent model to address these challenges. In this review, we reflect on 25 years of mammalian CRX research and discuss recent progress in elucidating the distinct pathogenic mechanisms of four CRX coding variant classes. We highlight how in vitro biochemical studies of CRX protein functions facilitate understanding CRX regulatory principles in animal models. We conclude with a brief discussion of the emerging systems biology approaches that could accelerate precision medicine for CRX-linked diseases and beyond.

11.
Genome Res ; 34(2): 243-255, 2024 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-38355306

RESUMEN

Dozens of variants in the gene for the homeodomain transcription factor (TF) cone-rod homeobox (CRX) are linked with human blinding diseases that vary in their severity and age of onset. How different variants in this single TF alter its function in ways that lead to a range of phenotypes is unclear. We characterized the effects of human disease-causing variants on CRX cis-regulatory function by deploying massively parallel reporter assays (MPRAs) in mouse retina explants carrying knock-ins of two variants, one in the DNA-binding domain (p.R90W) and the other in the transcriptional effector domain (p.E168d2). The degree of reporter gene dysregulation in these mutant Crx retinas corresponds with their phenotypic severity. The two variants affect similar sets of enhancers, and p.E168d2 has distinct effects on silencers. Cis-regulatory elements (CREs) near cone photoreceptor genes are enriched for silencers that are derepressed in the presence of p.E168d2. Chromatin environments of CRX-bound loci are partially predictive of episomal MPRA activity, and distal elements whose accessibility increases later in retinal development are enriched for CREs with silencer activity. We identified a set of potentially pleiotropic regulatory elements that convert from silencers to enhancers in retinas that lack a functional CRX effector domain. Our findings show that phenotypically distinct variants in different domains of CRX have partially overlapping effects on its cis-regulatory function, leading to misregulation of similar sets of enhancers while having a qualitatively different impact on silencers.


Asunto(s)
Proteínas de Homeodominio , Transactivadores , Animales , Humanos , Ratones , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos , Retina/metabolismo , Células Fotorreceptoras Retinianas Conos/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/genética
12.
Immun Inflamm Dis ; 12(1): e1134, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38270318

RESUMEN

INTRODUCTION: This study aimed to investigate the role of immunocompetence in chronic hepatitis B (CHB) patients with normal alanine transaminase (ALT) levels and negative hepatitis B e antigen (HBeAg) in the risk assessments of the progression of liver fibrosis. METHODS: We collected the clinical data of 57 patients with CHB, with normal ALT levels and negative HBeAg from December 2020 to December 2022. With hepatitis B virus (HBV) DNA > 20 IU/mL and ALT ≤ 40 U/L, these patients had never undergone antiviral therapy. The levels of CD4+ , CD4+ CD25+ , CD8+ , and CD4+ CD25+ CD127LOW regulatory T cells (Tregs) in the patients were detected using flow cytometry; the liver stiffness measurement (LSM) values of the patients were detected using Fibroscan. RESULTS: There was a statistically significant difference between the levels of fibrosis-4 (FIB-4) and hepatitis B surface antigen (HBsAg) when the cutoff point was HBsAg ≥ 1500 (p < .001). FIB-4 was negatively correlated with HBsAg (R = -0.291, p = .028) and positively correlated with age (R = 0.787, p < .001). LSM was negatively correlated with Treg but this correlation was not statistically significant (p > .05). Findings based on the analysis using logistic regression were as follows: (i) age was the independent risk factor when FIB-4 was used as the indicator for assessing liver fibrosis; (ii) Treg was the independent risk factor when LSM was used as the indicator for assessing liver fibrosis. When Treg was used to predict liver fibrosis, the cutoff value, diagnostic efficacy, area under the receiver operating characteristic (ROC) curve, and p value of the ROC curve were 6.875, 0.641, 0.84, and .027, respectively. CONCLUSION: Age and Treg are independent risk factors for progressive liver fibrosis. The cutoff value of Treg > 6.81 indicates the need for timely antiviral treatment and can serve as an indicator for evaluating liver fibrosis.


Asunto(s)
Antígenos e de la Hepatitis B , Hepatitis B , Humanos , Alanina Transaminasa , Antígenos de Superficie de la Hepatitis B , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/etiología , Hepatitis Crónica , Inmunocompetencia
13.
Dalton Trans ; 53(5): 2159-2166, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38189199

RESUMEN

The cationic and neutral boron-diamide precursors are employed to target the inclusion of N2 and N-P molecular fragments. The species (HCN(Dipp))2BNH25, and (H2CN(Dipp))2BNH26 were prepared. While efforts to oxidize with [NO]+ gave mixtures of products, reactions with N2H4 gave the salts [(HCN(Dipp))2B(NHNH3)][O3SCF3] 7 [(H2CN(Dipp))2B(NHNH3)][O3SCF3] 8. Excess N2H4 gave the neutral species (HCN(Dipp))2B(NHNH2) 9 and (H2CN(Dipp))2B(NHNH2) 10, respectively. The species (H2CN(Dipp))2B(N3) 11 was prepared for comparative purposes. Turning to related NP species, compound 6 was converted to (HCN(Dipp))2B(NHPCl2) 12, while (HCN(Dipp))2BNK(SiMe3) 14 was used to give (HCN(Dipp))2BN(SiMe3)PCl215. Replacement of one of the chlorides gave (HCN(Dipp))2BN(SiMe3)PCl(OSO2CF3) 16 which converts to [(HCN(Dipp))2BNPCl]217. Similarly heating 15 afforded 17. The insights for the synthesis of further boron-N2 and boron-NP derivatives are discussed.

14.
Autophagy ; 20(2): 329-348, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37776538

RESUMEN

Chemotherapeutic resistance is one of the most common reasons for poor prognosis of patients with nasopharyngeal carcinoma (NPC). We found that CENPN can promote the growth, proliferation and apoptosis resistance of NPC cells, but its relationship with chemotherapeutic resistance in NPC is unclear. Here we verified that the CENPN expression level in NPC patients was positively correlated with the degree of paclitaxel (PTX) resistance and a poor prognosis through analysis of clinical cases. VAMP8 expression was significantly increased after knockdown of CENPN by transcriptome sequencing. We found in cell experiments that CENPN inhibited macroautophagy/autophagy and VAMP8 expression and significantly increased PTX resistance. Overexpression of CENPN reduced the inhibitory effects of PTX on survival, cell proliferation, cell cycle progression and apoptosis resistance in NPC cells by inhibiting autophagy. In turn, knockdown of CENPN can affect the phenotype of NPC cells by increasing autophagy to achieve PTX sensitization. Sequential knockdown of CENPN and VAMP8 reversed the PTX-sensitizing effect of CENPN knockdown alone. Experiments in nude mice confirmed that knockdown of CENPN can increase VAMP8 expression, enhance autophagy and increase the sensitivity of NPC cells to PTX. Mechanistic studies showed that CENPN inhibited the translocation of p-CREB into the nucleus of NPC cells, resulting in the decreased binding of p-CREB to the VAMP8 promoter, thereby inhibiting the transcription of VAMP8. These results demonstrate that CENPN may be a marker for predicting chemotherapeutic efficacy and a potential target for inducing chemosensitization to agents such as PTX.Abbreviations: 3-MA: 3-methyladenine; ATG5: autophagy related 5; CENPN: centromere protein N; CQ: chloroquine; CREB: cAMP responsive element binding protein; ChIP: chromatin immunoprecipitation assay; IC50: half-maximal inhibitory concentration; LAMP2A: lysosomal associated membrane protein 2A; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; NPC: nasopharyngeal carcinoma; NPG: nasopharyngitis; oeCENPN: overexpressed CENPN; PTX: paclitaxel; RAPA: rapamycin; RNA-seq: transcriptome sequencing; shCENPN: small hairpin RNA expression vector targeting the human CENPN gene; shCENPN-shVAMP8: sequential knockdown targeting the human CENPN gene and VAMP8 gene; shVAMP8: small hairpin RNA expression vector targeting the human VAMP8 gene; TEM: transmission electron microscopy; TIR: tumor inhibitory rate; VAMP8: vesicle associated membrane protein 8.


Asunto(s)
Neoplasias Nasofaríngeas , Paclitaxel , Animales , Ratones , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Ratones Desnudos , Autofagia/genética , Línea Celular Tumoral , ARN Interferente Pequeño/farmacología , Proteínas R-SNARE/metabolismo , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Proteínas Cromosómicas no Histona/farmacología
15.
Int Arch Allergy Immunol ; 185(2): 124-132, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37913762

RESUMEN

INTRODUCTION: The incidence of allergic rhinitis (AR) is increasing year by year, and the pathogenesis is complex, in which diet may play an important role. The role of polyunsaturated fatty acids (PUFAs) in AR is still controversial. Previous studies have looked at the effects of PUFA during pregnancy, childhood, and adolescence. In this study, we aimed to determine the association between dietary intake of PUFA and AR in adults. METHODS: We used the NHANES database from 2005 to 2006 to include a total of 4,211 adult subjects. We collected dietary PUFA intake data and information on AR. Logistic regression and restricted cubic spline models were constructed to examine the association between PUFA intake and AR in adults. The t test was used to compare daily PUFA intakes in patients with and without AR. RESULTS: In the fully adjusted model (OR: 1.016; 95% CI: 1.003; 1.028), PUFA intake was positively correlated with allergic symptoms, hay fever, and AR in adults (p < 0.05). In addition, daily PUFA intake was significantly higher in people with allergic symptoms, hay fever, and AR than in people without the disease (p < 0.01). CONCLUSIONS: Our results suggest a positive association between dietary PUFA intake and AR in adults to a certain extent. Future studies on dietary PUFA dose will provide new strategies for the prevention and treatment of allergic diseases such as AR related to non-pharmaceutical interventions.


Asunto(s)
Rinitis Alérgica Estacional , Rinitis Alérgica , Adulto , Embarazo , Femenino , Adolescente , Humanos , Niño , Estudios Transversales , Encuestas Nutricionales , Dieta , Rinitis Alérgica/epidemiología , Ácidos Grasos Insaturados
16.
Dalton Trans ; 53(2): 439-443, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38093643

RESUMEN

Reactions of (tBuO2CN)2 with Lewis acids and FLPs have previously been shown to prompt the formation of diazene compounds. In this work, we show that the reaction of (tBuO2CN)2 with 9-BBN leads to a bicyclic heterocyclic product (tBuOCO(BBN)CN)21. In contrast, the reactions of (tBuO2CN)2 with BF3 or [Et3Si][B(C6F5)4] lead to the isolation of [tBuNHNH2tBu][BF4] 2 and [tBuN(H)NtBu][B(C6F5)4] 3, respectively. The mechanism for the formation of 2 is probed computationally, demonstrating that steric and electronic considerations of the Lewis acid impact the reaction pathway.

17.
Hear Res ; 440: 108913, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37939412

RESUMEN

Aging is an inevitable phase in mammals that leads to health impairments, including hearing loss. Age-related hearing loss (AHL) leads to psychosocial problems and cognitive decline in the elderly. In this study, mean thresholds of auditory brainstem responses (ABR) and distortion-product otoacoustic emissions (DPOAE) increased at multiple frequencies in aged rats (14 months old) compared to young rats (2 months old). Using untargeted ultra-high performance liquid chromatography-mass spectroscopy (LC-MS), we quantified molecular metabolic markers in the cochlea of aged rats with hearing loss. A total of 137 different metabolites were identified in two groups, highlighting several prominent metabolic pathways related to purine metabolism; glycine, serine, and threonine metabolism; arginine and proline metabolism; and pyrimidine metabolism. In addition, the beneficial effects of purine supplementation were demonstrated in a mimetic model of senescent marginal cells (MCs). Overall, altered metabolic profiling is both the cause and manifestation of pathology, and our results suggest that cellular senescence and dysfunctional cochlear metabolism may contribute to the progression of AHL. These findings are seminal in elucidating the pathophysiological mechanisms underlying AHL and serve as a basis for future clinical predictions and interventions in AHL.


Asunto(s)
Emisiones Otoacústicas Espontáneas , Presbiacusia , Humanos , Anciano , Ratas , Animales , Lactante , Emisiones Otoacústicas Espontáneas/fisiología , Cóclea/fisiología , Envejecimiento/fisiología , Potenciales Evocados Auditivos del Tronco Encefálico , Biomarcadores , Purinas , Umbral Auditivo/fisiología , Mamíferos
18.
J Transl Med ; 21(1): 792, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940975

RESUMEN

OBJECTIVE: Investigating the impact of centromere protein N (CENP-N) on radiosensitivity of nasopharyngeal carcinoma (NPC) cells. METHODS: Using immunohistochemistry and immunofluorescence to detect CENP-N expression in tissues from 35 patients with radiosensitive or radioresistant NPC. Assessing the effect of combined CENP-N knockdown and radiotherapy on various cellular processes by CCK-8, colony formation, flow cytometry, and Western blotting. Establishing a NPC xenograft model. When the tumor volume reached 100 mm3, a irradiation dose of 6 Gy was given, and the effects of the combined treatment were evaluated in vivo using immunofluorescence and Western blotting techniques. RESULTS: The level of CENP-N was significantly reduced in radiosensitive tissues of NPC (p < 0.05). Knockdown of CENP-N enhanced NPC radiosensitivity, resulting in sensitizing enhancement ratios (SER) of 1.44 (5-8 F) and 1.16 (CNE-2Z). The combined treatment showed significantly higher levels of proliferation suppression, apoptosis, and G2/M phase arrest (p < 0.01) compared to either CENP-N knockdown alone or radiotherapy alone. The combined treatment group showed the highest increase in Bax and γH2AX protein levels, whereas the protein Cyclin D1 exhibited the greatest decrease (p < 0.01). However, the above changes were reversed after treatment with AKT activator SC79. In vivo, the mean volume and weight of tumors in the radiotherapy group were 182 ± 54 mm3 and 0.16 ± 0.03 g. The mean tumor volume and weight in the combined treatment group were 84 ± 42 mm3 and 0.04 ± 0.01 g. CONCLUSION: Knockdown of CENP-N can enhance NPC radiosensitivity by inhibiting AKT/mTOR.


Asunto(s)
Neoplasias Nasofaríngeas , Proteínas Proto-Oncogénicas c-akt , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/radioterapia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Línea Celular Tumoral , Tolerancia a Radiación/genética , Serina-Treonina Quinasas TOR , Proliferación Celular/efectos de la radiación , Apoptosis/genética
19.
Elife ; 122023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37963072

RESUMEN

Homeodomain transcription factors (HD TFs) are instrumental to vertebrate development. Mutations in HD TFs have been linked to human diseases, but their pathogenic mechanisms remain elusive. Here, we use Cone-Rod Homeobox (CRX) as a model to decipher the disease-causing mechanisms of two HD mutations, p.E80A and p.K88N, that produce severe dominant retinopathies. Through integrated analysis of molecular and functional evidence in vitro and in knock-in mouse models, we uncover two novel gain-of-function mechanisms: p.E80A increases CRX-mediated transactivation of canonical CRX target genes in developing photoreceptors; p.K88N alters CRX DNA-binding specificity resulting in binding at ectopic sites and severe perturbation of CRX target gene expression. Both mechanisms produce novel retinal morphological defects and hinder photoreceptor maturation distinct from loss-of-function models. This study reveals the distinct roles of E80 and K88 residues in CRX HD regulatory functions and emphasizes the importance of transcriptional precision in normal development.


Asunto(s)
Enfermedades de la Retina , Transactivadores , Animales , Humanos , Ratones , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Mutación Missense , Retina/metabolismo , Enfermedades de la Retina/patología , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
20.
Res Sq ; 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38014002

RESUMEN

Single-cell sequencing has revolutionized the scale and resolution of molecular profiling of tissues and organs. Here, we present an integrated multimodal reference atlas of the most accessible portion of the mammalian central nervous system, the retina. We compiled around 2.4 million cells from 55 donors, including 1.4 million unpublished data points, to create a comprehensive human retina cell atlas (HRCA) of transcriptome and chromatin accessibility, unveiling over 110 types. Engaging the retina community, we annotated each cluster, refined the Cell Ontology for the retina, identified distinct marker genes, and characterized cis-regulatory elements and gene regulatory networks (GRNs) for these cell types. Our analysis uncovered intriguing differences in transcriptome, chromatin, and GRNs across cell types. In addition, we modeled changes in gene expression and chromatin openness across gender and age. This integrated atlas also enabled the fine-mapping of GWAS and eQTL variants. Accessible through interactive browsers, this multimodal cross-donor and cross-lab HRCA, can facilitate a better understanding of retinal function and pathology.

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