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1.
Appl Opt ; 63(12): 3212-3218, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856469

RESUMO

In this paper, a broadband terahertz metasurface dedicated to cross-polarization conversion was designed, fabricated, and assessed. The metasurface, comprising two nested double-split rings, features an inherent insensitivity to the angle of incidence. Simulations reveal that the converter achieves a >99% polarization conversion efficiency across the 90-140 GHz range. Moreover, it maintains a >90% polarization conversion ratio (PCR), even at a 50° incidence angle. The sample, featuring 50×70 arrays, was fabricated, and the relevant experimental results align closely with the simulated outcomes. The metasurface characteristics can markedly enhance the performance of cross-polarization converters operating in the terahertz range.

2.
ACS Nano ; 18(28): 18560-18571, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38941591

RESUMO

High-performance thermal interface materials (TIMs) are highly desired for high-power electronic devices to accelerate heat dissipation. However, the inherent trade-off conflict between achieving high thermal conductivity and excellent compliance of filler-enhanced TIMs results in the unsatisfactory interfacial heat transfer efficiency of existing TIM solutions. Here, we report the graphene fiber (GF)-based elastic TIM with metal-level thermal conductivity via mechanical-electric dual-field synergistic alignment engineering. Compared with state-of-the-art carbon fiber (CF), GF features both superb high thermal conductivity of ∼1200 W m-1 K-1 and outstanding flexibility. Under dual-field synergistic alignment regulation, GFs are vertically aligned with excellent orientation (0.88) and high array density (33.5 mg cm-2), forming continuous thermally conductive pathways. Even at a low filler content of ∼17 wt %, GF-based TIM demonstrates extraordinarily high through-plane thermal conductivity of up to 82.4 W m-1 K-1, exceeding most CF-based TIMs and even comparable to commonly used soft indium foil. Benefiting from the low stiffness of GF, GF-based TIM shows a lower compressive modulus down to 0.57 MPa, an excellent resilience rate of 95% after compressive cycles, and diminished contact thermal resistance as low as 7.4 K mm2 W-1. Our results provide a superb paradigm for the directed assembly of thermally conductive and flexible GFs to achieve scalable and high-performance TIMs, overcoming the long-standing bottleneck of mechanical-thermal mismatch in TIM design.

3.
Anal Chim Acta ; 1311: 342734, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38816163

RESUMO

Photodynamic therapy (PDT), characterized by high treatment efficiency, absence of drug resistance, minimal trauma, and few side effects, has gradually emerged as a novel and alternative clinical approach compared to traditional surgical resection, chemotherapy and radiation. Whereas, considering the limited diffusion distance and short lifespan of reactive oxygen species (ROS), as well as the hypoxic tumor microenvironment, it is crucial to design photosensitizers (PSs) with suborganelle specific targeting ability and low-oxygen dependence for accurate and highly efficient photodynamic therapy. In this study, we have meticulously designed three PSs, namely CIH, CIBr, and CIPh, based on molecular engineering. Theoretical calculation demonstrate that the three compounds possess good molecular planarity with calculated S1-T1 energy gaps (ΔES1-T1) of 1.04 eV for CIH, 0.92 eV for CIBr, and 0.84 eV for CIPh respectively. Notably, CIPh showcases remarkable dual subcellular targeting capability towards lipid droplets (LDs) and mitochondria owing to the synergistic effect of lipophilicity derived from coumarin's inherent properties combined with electropositivity conferred by indole salt cations. Furthermore, CIPh demonstrates exclusive release of singlet oxygen (1O2)and highly efficient superoxide anion free radicals(O2⦁-) upon light irradiation supported by its smallest S1-T1 energy gap (ΔES1-T1 = 0.84 eV). This leads to compromised integrity of LDs along with mitochondrial membrane potential, resulting in profound apoptosis induction in HepG2 cells. This successful example of molecular engineering guided by density functional theory (DFT) provides valuable experience for the development of more effective PSs with superior dual targeting specificity. It also provides a new idea for the development of advanced PSs with efficient and accurate ROS generation ability towards fluorescence imaging-guided hypoxic tumor therapy.


Assuntos
Gotículas Lipídicas , Mitocôndrias , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio , Humanos , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fotoquimioterapia , Sobrevivência Celular/efeitos dos fármacos
4.
Talanta ; 276: 126281, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788386

RESUMO

In the medical field, changes in interleukin-6 (IL-6) concentration serve as essential biomarkers for monitoring and diagnosing various conditions, including acute inflammatory responses such as those seen in trauma and burns, and chronic illnesses like cancer. This paper detailed a label-free electrochemical aptamer sensor designed for IL-6 quantification. A composite material consisting of Ti3C2Tx and MoS2 was successfully synthesized to fabricate this sensor. The synergistic effect of MoS2's catalytic action on hydrogen peroxide (H2O2), used as a signalling marker, when combined with the exceptional conductivity and large specific surface area of Ti3C2Tx, not only enables an increased loading of MoS2 but also significantly boosts the electrochemical response. The in situ-reduced Au NPs provided stable immobilization sites for DNA aptamers (DNAapt) and facilitated electron transfer, ensuring accurate IL-6 recognition. Under optimal conditions, the aptamer sensor exhibited a wide linear range (5 pg/mL to 100 ng/mL) and a low limit of detection (LOD) of 2.9 pg/mL. Its sensing performance in human serum samples highlights its potential as a promising clinical analysis tool.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnicas Eletroquímicas , Interleucina-6 , Nanopartículas Metálicas , Humanos , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Dissulfetos/química , Técnicas Eletroquímicas/métodos , Ouro/química , Peróxido de Hidrogênio/química , Interleucina-6/sangue , Interleucina-6/análise , Limite de Detecção , Nanopartículas Metálicas/química , Molibdênio/química , Titânio/química
5.
Soft Matter ; 20(23): 4591-4607, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38805009

RESUMO

The limitations in previous dissipative particle dynamics (DPD) studies confined simulations to a narrow resin range. This study refines DPD parameter calculation methodology, extending its application to diverse polymer materials. Using a bottom-up approach with molecular dynamics (MD) simulations, we evaluated solubility parameters and bead number density governing nonbonded interactions via the Flory-Huggins parameter and covalent-bonded interactions. Two solubility parameter methods, Hildebrand and Krevelen-Hoftyzer, were compared for DPD simulations. The Hildebrand method, utilizing MD simulations, demonstrates higher consistency and broader applicability in determining solubility parameters for all DPD particles. The DPD/MD curing reaction process was examined in three epoxy systems: DGEBA/4,4'-DDS, DGEBA/MPDA and DGEBA/DETA. Calculations for the curing profile, gelation point, radial distribution function and branch ratio were performed. Compared to MD data for DGEBA/4,4'-DDS, the maximum deviation in secondary reactions between epoxy and amine groups according to DPD simulations with Krevelen-Hoftyzer was 14.8%, while with the Hildebrand method, it was 1.7%. The accuracy of the DPD curing reaction in reproducing the structural properties verifies its expanded application to general polymeric material simulations. The proposed curing DPD simulations, with a short run time and minimal computational resources, contributes to high-throughput screening for optimal resins and investigates mesoscopic inhomogeneous structures in large resin systems.

6.
Small ; : e2400415, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698600

RESUMO

Highly flexible and superelastic aerogels at large deformation have become urgent mechanical demands in practical uses, but both properties are usually exclusive. Here a trans-scale porosity design is proposed in graphene nanofibrous aerogels (GNFAs) to break the trade-off between high flexibility and superelasticity. The resulting GNFAs can completely recover after 1000 fatigue cycles at 60% folding strain, and notably maintain excellent structural integrity after 10000 cycles at 90% compressive strain, outperforming most of the reported aerogels. The mechanical robustness is demonstrated to be derived from the trans-scale porous structure, which is composed of hyperbolic micropores and porous nanofibers to enable the large elastic deformation capability. It is further revealed that flexible and superelastic GNFAs exhibit high sensitivity and ultrastability as an electrical sensors to detect tension and flexion deformation. As proof, The GNFA sensor is implemented onto a human finger and achieves the intelligent recognition of sign language with high accuracy by multi-layer artificial neural network. This study proposes a highly flexible and elastic graphene aerogel for wearable human-machine interfaces in sensor technology.

7.
Org Biomol Chem ; 22(20): 4089-4095, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38695080

RESUMO

Transition-metal-catalyzed aromatic olefination through direct C-H activation represents an atom and step-economic route for versatile pharmaceutical syntheses, and in many cases, different stoichiometric oxidants are frequently employed for achieving a reasonable catalytic efficiency of the transition metal ions. Herein, we report a Lewis acid promoted Pd(II)-catalyzed acetanilide olefination reaction with atmospheric dioxygen as the oxidant source. The linkage of the Lewis acid to the Pd(II) species through a diacetate bridge significantly improved its catalytic efficiency, and independent kinetic studies on the olefination step revealed that adding the Lewis acid significantly accelerated the olefination rate as well as the C-H activation step. A strong basicity of the internal base in the Pd(II) salt also benefited the olefination reaction plausibly through base-assisted ß-hydride elimination.

8.
Pest Manag Sci ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808579

RESUMO

BACKGROUND: Transketolase (TKL, EC 2.2.1.1) is a key enzyme in the pentose phosphate pathway and Calvin cycle, and is expected to act as a herbicidal site-of-action. On the basis of TKL, we designed and synthesized a series of 1-oxy-propionamide-pyrazole-3-carboxylate analogues and evaluated their herbicidal activities. RESULTS: Methyl 1-methyl-5-((1-oxo-1-((4-(trifluoromethyl)phenyl)amino)propan-2-yl)oxy)-1H-pyrazole-3-carboxylate (C23) and methyl 1-methyl-5-((1-oxo-1-((perfluorophenyl)amino)propan-2-yl)oxy)-1H-pyrazole-3-carboxylate (C33) were found to provide better growth-inhibition activities against Digitaria sanguinalis root than those of nicosulfuron, mesotrione and pretilachlor at 200 mg L-1 using the small-cup method. These compounds were also identified as promising compounds in pre-emergence and postemergence herbicidal-activity experiments, with relatively good inhibitory effects toward Amaranthus retroflexus and D. sanguinalis at 150 g ai ha-1. In addition, enzyme inhibition assays and molecular docking studies revealed that C23 and C33 interact favourably with SvTKL (Setaria viridis TKL). CONCLUSION: C23 and C33 are promising lead TKL inhibitors for the optimization of new herbicides. © 2024 Society of Chemical Industry.

9.
Int J Surg ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38788195

RESUMO

OBJECTIVE: Most bladder cancers are non-muscle invasive bladder cancer (NMIBC), and transurethral resection of bladder tumors (TURBT) is the standard treatment. However, postoperative recurrence remains a significant challenge, and the influence of bladder tumor location on prognosis is still unclear. This study aims to investigate how tumor location affects the prognosis of NMIBC patients undergoing TURBT and to identify the optimal surgical approach. METHODS: A multicenter study was conducted, which included Chinese NMIBC data from 15 hospitals (1996-2019) and data from 17 registries of the Surveillance, Epidemiology, and End Results database (SEER) (2000-2020). Patients initially diagnosed with NMIBC and undergoing TURBT or partial cystectomy were analyzed, with cases lost to follow-up or with missing data excluded. The study investigated the overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) among patients with different tumor locations. Kaplan-Meier, Cox regression, and propensity score matching methods were employed to explore the association between tumor location and prognosis. Stratified populations were analyzed to minimize bias. RESULTS: This study included 118,477 NMIBC patients and highlighted tumor location as a crucial factor impacting post-TURBT prognosis. Both anterior wall and dome tumors independently predicted adverse outcomes in two cohorts. For anterior wall tumors, the Chinese cohort showed hazard ratios (HR) for OS of 4.35 (P < 0.0001); RFS of 2.21 (P < 0.0001); SEER cohort OS HR of 1.10 (P = 0.0001); DSS HR of 1.13 (P = 0.0183). Dome tumors displayed similar trends (Chinese NMIBC cohort OS HR of 7.91 (P < 0.0001); RFS HR of 2.12 (P < 0.0001); SEER OS HR of 1.05 (P = 0.0087); DSS HR of 1.14 (P = 0.0006)). Partial cystectomy significantly improved the survival of dome tumor patients compared to standard TURBT treatment (P < 0.01). CONCLUSION: This study reveals the significant impact of tumor location in NMIBC patients on the outcomes of TURBT treatment, with tumors in the anterior wall and bladder dome showing poor post-TURBT prognosis. Compared to TURBT treatment, partial cystectomy improves the prognosis for bladder dome tumors. This study provides guidance for personalized treatment and prognosis management for NMIBC patients.

10.
Nano Lett ; 24(14): 4256-4264, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557048

RESUMO

Biological materials exhibit fascinating mechanical properties for intricate interactions at multiple interfaces to combine superb toughness with wondrous strength and stiffness. Recently, strong interlayer entanglement has emerged to replicate the powerful dissipation of natural proteins and alleviate the conflict between strength and toughness. However, designing intricate interactions in a strong entanglement network needs to be further explored. Here, we modulate interlayer entanglement by introducing multiple interactions, including hydrogen and ionic bonding, and achieve ultrahigh mechanical performance of graphene-based nacre fibers. Two essential modulating trends are directed. One is modulating dynamic hydrogen bonding to improve the strength and toughness up to 1.58 GPa and 52 MJ/m3, simultaneously. The other is tailoring ionic coordinating bonding to raise the strength and stiffness, reaching 2.3 and 253 GPa. Modulating various interactions within robust entanglement provides an effective approach to extend performance limits of bioinspired nacre and optimize multiscale interfaces in diverse composites.

11.
iScience ; 27(5): 109674, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38646169

RESUMO

Cancer-associated fibroblasts (CAFs) have been shown to play a key role in prostate cancer treatment resistance, but the role of CAFs in the initial course of enzalutamide therapy for prostate cancer remains unclear. Our research revealed that CAFs secrete CCL5, which promotes the upregulation of androgen receptor (AR) expression in prostate cancer cells, leading to resistance to enzalutamide therapy. Furthermore, CCL5 also enhances the expression of tumor programmed death-ligand 1 (PD-L1), resulting in immune escape. Mechanistically, CCL5 binds to the receptor CCR5 on prostate cancer cells and activates the AKT signaling pathway, leading to the upregulation of AR and PD-L1. The CCR5 antagonist maraviroc to inhibit the CAFs mediated CCL5 signaling pathway can effectively reduce the expression of AR and PD-L1, and improve the efficacy of enzalutamide. This study highlights a promising therapeutic approach targeting the CCL5-CCR5 signaling pathway to improve the effectiveness of enzalutamide.

12.
Biochem Biophys Res Commun ; 714: 149956, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663095

RESUMO

BACKGROUND: Maize is a major cereal crop world widely, however, the yield of maize is frequently limited by dehydration and even death of plants, which resulted from osmotic stress such as drought and salinity. Dissection of molecular mechanisms controlling stress tolerance will enable plant scientists and breeders to increase crops yield by manipulating key regulatory components. METHODS: The candidate OSR1 gene was identified by map-based cloning. The expression level of OSR1 was verified by qRT-PCR and digital PCR in WT and osr1 mutant. Electrophoretic mobility shift assay, transactivation activity assay, subcellular localization, transcriptome analysis and physiological characters measurements were conducted to analyze the function of OSR1 in osmotic stress resistance in maize. RESULTS: The osr1 mutant was significantly less sensitive to osmotic stress than the WT plants and displayed stronger water-holding capacity, and the OSR1 homologous mutant in Arabidopsis showed a phenotype similar with maize osr1 mutant. Differentially expressed genes (DEGs) were identified between WT and osr1 under osmotic stress by transcriptome analysis, the expression levels of many genes, such as LEA, auxin-related factors, PPR family members, and TPR family members, changed notably, which may primarily involve in osmotic stress or promote root development. CONCLUSIONS: OSR1 may serve as a negative regulatory factor in response to osmotic stress in maize. The present study sheds new light on the molecular mechanisms of osmotic stress in maize.


Assuntos
Regulação da Expressão Gênica de Plantas , Pressão Osmótica , Proteínas de Plantas , Fatores de Transcrição , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Mutação , Estresse Fisiológico/genética , Perfilação da Expressão Gênica
13.
Phys Med Biol ; 69(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38640915

RESUMO

Objective. Beam hardening (BH) artifacts in computed tomography (CT) images originate from the polychromatic nature of x-ray photons. In a CT system with a bowtie filter, residual BH artifacts remain when polynomial fits are used. These artifacts lead to worse visuals, reduced contrast, and inaccurate CT numbers. This work proposes a pixel-by-pixel correction (PPC) method to reduce the residual BH artifacts caused by a bowtie filter.Approach. The energy spectrum for each pixel at the detector after the photons pass through the bowtie filter was calculated. Then, the spectrum was filtered through a series of water slabs with different thicknesses. The polychromatic projection corresponding to the thickness of the water slab for each detector pixel could be obtained. Next, we carried out a water slab experiment with a mono energyE= 69 keV to get the monochromatic projection. The polychromatic and monochromatic projections were then fitted with a 2nd-order polynomial. The proposed method was evaluated on digital phantoms in a virtual CT system and phantoms in a real CT machine.Main results. In the case of a virtual CT system, the standard deviation of the line profile was reduced by 23.8%, 37.3%, and 14.3%, respectively, in the water phantom with different shapes. The difference of the linear attenuation coefficients (LAC) in the central and peripheral areas of an image was reduced from 0.010 to 0.003cm-1and 0.007cm-1to 0 in the biological tissue phantom and human phantom, respectively. The method was also validated using CT projection data obtained from Activion16 (Canon Medical Systems, Japan). The difference in the LAC in the central and peripheral areas can be reduced by a factor of two.Significance. The proposed PPC method can successfully remove the cupping artifacts in both virtual and authentic CT images. The scanned object's shapes and materials do not affect the technique.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Humanos
14.
Int J Surg ; 110(6): 3190-3202, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38498388

RESUMO

BACKGROUND: The management of oligometastatic prostate cancer, defined by its few metastatic sites, poses distinct clinical dilemmas. Debates persist regarding the most effective treatment approach, with both cytoreductive surgery and radiotherapy being key contenders. The purpose of this research is to thoroughly evaluate and compare the effectiveness of these two treatments in managing patients with oligometastatic prostate cancer. METHODS: A comprehensive search of the literature was carried out to find pertinent publications that compared the results of radiation and cytoreductive surgery for oligometastatic prostate cancer. A meta-analysis was conducted in order to evaluate both short-term and long-term survival. Furthermore, utilizing institutional patient data, a retrospective cohort research was conducted to offer practical insights into the relative performances of the two treatment regimens. RESULTS: Five relevant studies' worth of data were included for this meta-analysis, which included 1425 patients with oligometastatic prostate cancer. The outcomes showed that, in comparison to radiation, cytoreductive surgery was linked to a substantially better cancer-specific survival (CSS) [hazard ratio (HR): 0.70, 95% (CI): 0.59-0.81, P <0.001] and overall survival (OS) [HR, 0.80; 95% (CI), 0.77-0.82; P <0.01]. The two therapy groups' Progression-Free Survival (PFS) and Castration-Resistant Prostate Cancer-Free Survival (CRPCFS), however, did not differ significantly (HR: 0.56, 95% CI: 0.17-1.06; HR: 0.67, 95% CI: 0.26-1.02, respectively). Out of the 102 patients who were recruited in the retrospective cohort research, 36 had cytoreductive surgery (CRP), 36 had radiation therapy (primary lesion), and 30 had radiation therapy (metastatic lesion). The follow-up time was 46.3 months (18.6-60.0) on average. The enhanced OS in the CRP group [OS interquartile range (IQR): 45-60 months] in comparison to the radiation group (OS IQR: 39.0-59.0 months and 25.8-55.0 months, respectively) was further supported by the cohort research. Furthermore, CRP had a better OS than both radiation (primary region) and radiotherapy (metastatic region), with the latter two therapeutic methods having similar OS. CONCLUSION: This meta-analysis and retrospective research provide valuable insights into the comparative efficacy of cytoreductive surgery and radiotherapy for oligometastatic prostate cancer. While short-term survival (PFS, CRPCFS) was similar between the two groups, cytoreductive surgery exhibited superior CSS and OS. Adverse event rates were manageable in both modalities. These findings contribute to informed treatment decision-making for clinicians managing oligometastatic prostate cancer patients. Further prospective studies and randomized controlled trials are essential to corroborate these results and guide personalized therapeutic approaches for this distinct subset of patients.


Assuntos
Procedimentos Cirúrgicos de Citorredução , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Estudos Retrospectivos , Resultado do Tratamento , Metástase Neoplásica/radioterapia
15.
Biomed Opt Express ; 15(3): 1437-1452, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38495700

RESUMO

This study presents denoiseGAN, a novel semi-supervised generative adversarial network, for denoising adaptive optics (AO) retinal images. By leveraging both synthetic and real-world data, denoiseGAN effectively addresses various noise sources, including blur, motion artifacts, and electronic noise, commonly found in AO retinal imaging. Experimental results demonstrate that denoiseGAN outperforms traditional image denoising methods and the state-of-the-art conditional GAN model, preserving retinal cell structures and enhancing image contrast. Moreover, denoiseGAN aids downstream analysis, improving cell segmentation accuracy. Its 30% faster computational efficiency makes it a potential choice for real-time AO image processing in ophthalmology research and clinical practice.

16.
J Exp Clin Cancer Res ; 43(1): 67, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429845

RESUMO

BACKGROUND: Docetaxel resistance represents a significant obstacle in the treatment of prostate cancer. The intricate interplay between cytokine signalling pathways and transcriptional control mechanisms in cancer cells contributes to chemotherapeutic resistance, yet the underlying molecular determinants remain only partially understood. This study elucidated a novel resistance mechanism mediated by the autocrine interaction of interleukin-11 (IL-11) and its receptor interleukin-11 receptor subunit alpha(IL-11RA), culminating in activation of the JAK1/STAT4 signalling axis and subsequent transcriptional upregulation of the oncogene c-MYC. METHODS: Single-cell secretion profiling of prostate cancer organoid was analyzed to determine cytokine production profiles associated with docetaxel resistance.Analysis of the expression pattern of downstream receptor IL-11RA and enrichment of signal pathway to clarify the potential autocrine mechanism of IL-11.Next, chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) was performed to detect the nuclear localization and DNA-binding patterns of phosphorylated STAT4 (pSTAT4). Coimmunoprecipitation and reporter assays were utilized to assess interaction between pSTAT4 and the cotranscription factor CREB-binding protein (CBP) as well as their role in c-MYC transcriptional activity. RESULTS: Autocrine secretion of IL-11 was markedly increased in docetaxel-resistant prostate cancer cells. IL-11 stimulation resulted in robust activation of JAK1/STAT4 signalling. Upon activation, pSTAT4 translocated to the nucleus and associated with CBP at the c-MYC promoter region, amplifying its transcriptional activity. Inhibition of the IL-11/IL-11RA interaction or disruption of the JAK1/STAT4 pathway significantly reduced pSTAT4 nuclear entry and its binding to CBP, leading to downregulation of c-MYC expression and restoration of docetaxel sensitivity. CONCLUSION: Our findings identify an autocrine loop of IL-11/IL-11RA that confers docetaxel resistance through the JAK1/STAT4 pathway. The pSTAT4-CBP interaction serves as a critical enhancer of c-MYC transcriptional activity in prostate cancer cells. Targeting this signalling axis presents a potential therapeutic strategy to overcome docetaxel resistance in advanced prostate cancer.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Interleucina-11 , Neoplasias da Próstata , Humanos , Masculino , Docetaxel/farmacologia , Regulação da Expressão Gênica , Interleucina-11/genética , Interleucina-11/metabolismo , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Transdução de Sinais , Fator de Transcrição STAT4/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética
17.
Retina ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38484106

RESUMO

PURPOSE: To investigate the temporal sequence of changes in the photoreceptor cell mosaic in patients with Stargardt disease type 1 (STGD1), using adaptive optics scanning laser ophthalmoscopy (AOSLO). METHODS: Two brothers with genetically confirmed STGD1 underwent comprehensive eye exams, spectral-domain optical coherence tomography (SD-OCT), fundus auto fluorescence (FAF) and AOSLO imaging 3 times over the course of 28 months. Confocal images of the cones and rods were obtained from the central fovea to 10 degrees inferiorly. Photoreceptors were counted in sampling windows at 100 µm intervals of 200 µm × 200 µm for cones and 50 µm × 50 µm for rods, using custom cell marking software with manual correction. Photoreceptor density and spacing were measured and compared across imaging sessions using one-way ANOVA. RESULTS: AOSLO revealed the younger brother had a 30% decline in foveal cone density after 8 months, followed by complete loss of foveal cones at 28 months; the older brother had no detectable foveal cones at baseline. In the peripheral macula, cone and rod spacings were greater than normal in both patients. The ratio of the cone spacing to rod spacing was greater than normal across all eccentricities, with a greater divergence closer to the foveal center. CONCLUSIONS: Cone cell loss may be an early pathogenetic step in Stargardt disease. AOSLO provides the capability to track individual photoreceptor changes longitudinally in Stargardt disease. SUMMARY STATEMENT: The pathogenetic mechanism of Stargardt disease remains poorly understood. We used high resolution AOSLO to track the progression of the disease and found cone cell loss may be an early pathogenetic step in Stargardt disease.

18.
World J Gastroenterol ; 30(2): 146-157, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38312116

RESUMO

BACKGROUND: Eosinophilic gastroenteritis (EGE) is a chronic recurrent disease with abnormal eosinophilic infiltration in the gastrointestinal tract. Glucocorticoids remain the most common treatment method. However, disease relapse and glucocorticoid dependence remain notable problems. To date, few studies have illuminated the prognosis of EGE and risk factors for disease relapse. AIM: To describe the clinical characteristics of EGE and possible predictive factors for disease relapse based on long-term follow-up. METHODS: This was a retrospective cohort study of 55 patients diagnosed with EGE admitted to one medical center between 2013 and 2022. Clinical records were collected and analyzed. Kaplan-Meier curves and log-rank tests were conducted to reveal the risk factors for long-term relapse-free survival (RFS). RESULTS: EGE showed a median onset age of 38 years and a slight female predominance (56.4%). The main clinical symptoms were abdominal pain (89.1%), diarrhea (61.8%), nausea (52.7%), distension (49.1%) and vomiting (47.3%). Forty-three (78.2%) patients received glucocorticoid treatment, and compared with patients without glucocorticoid treatments, they were more likely to have elevated serum immunoglobin E (IgE) (86.8% vs 50.0%, P = 0.022) and descending duodenal involvement (62.8% vs 27.3%, P = 0.046) at diagnosis. With a median follow-up of 67 mo, all patients survived, and 56.4% had at least one relapse. Six variables at baseline might have been associated with the overall RFS rate, including age at diagnosis < 40 years [hazard ratio (HR) 2.0408, 95% confidence interval (CI): 1.0082-4.1312, P = 0.044], body mass index (BMI) > 24 kg/m2 (HR 0.3922, 95%CI: 0.1916-0.8027, P = 0.014), disease duration from symptom onset to diagnosis > 3.5 mo (HR 2.4725, 95%CI: 1.220-5.0110, P = 0.011), vomiting (HR 3.1259, 95%CI: 1.5246-6.4093, P = 0.001), total serum IgE > 300 KU/L at diagnosis (HR 0.2773, 95%CI: 0.1204-0.6384, P = 0.022) and glucocorticoid treatment (HR 6.1434, 95%CI: 2.8446-13.2676, P = 0.003). CONCLUSION: In patients with EGE, younger onset age, longer disease course, vomiting and glucocorticoid treatment were risk factors for disease relapse, whereas higher BMI and total IgE level at baseline were protective.


Assuntos
Enterite , Eosinofilia , Gastrite , Glucocorticoides , Humanos , Feminino , Adulto , Masculino , Glucocorticoides/uso terapêutico , Estudos Retrospectivos , Enterite/diagnóstico , Enterite/complicações , Prognóstico , Doença Crônica , Vômito , Recidiva , Imunoglobulina E
19.
Biomater Sci ; 12(3): 650-659, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38168678

RESUMO

Androgen deprivation therapy is administered to suppress the growth of prostate cancer (PCa). However, some cells continue to proliferate independent of hormones, leading to the development of castration-resistant prostate cancer (CRPC). Overexpression of the epidermal growth factor receptor (EGFR) has been observed in CRPC and is associated with an unfavorable prognosis. Gefitinib (GEF) is an EGFR inhibitor used to treat patients with CRPC. Nevertheless, some clinical studies have reported that gefitinib does not result in prostate-specific antigen (PSA) or objectively measurable CRPC reactions. This lack of response may be attributed to the limited solubility in water, high side effects, low tumor aggregation, and insufficient tumor-specific reactions of GEF. In order to tackle these obstacles, we present a practical and efficient approach to administer GEF, encompassing the utilization of biocompatible nanostructures as a vehicle for drug delivery to augment its bioaccessibility and curative potency. Despite their small particle size, poly(D,L-lactide-co-glycolide) acid nanoparticles (PLGA NPs) exhibit a high drug-loading capacity, low toxicity, biocompatibility, biodegradability, and minimal immunogenicity. The drug delivery efficiency can be improved by employing GEF@PLGA NPs, which could also enhance drug cytotoxicity and impede the advancement of prostate cancer. Moreover, through experiments in vivo, it has been verified that GEF@PLGA NPs exhibit selective accumulation in the tumor and effectively restrain tumor growth. Therefore, the GEF@PLGA NPs hold great promise for the treatment of PCa.


Assuntos
Nanopartículas , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Gefitinibe , Antagonistas de Androgênios , Nanopartículas/química , Receptores ErbB , Tamanho da Partícula , Linhagem Celular Tumoral
20.
Org Biomol Chem ; 22(4): 823-830, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38174952

RESUMO

Aniline derivatives are important nitrogen-containing compounds with wide applications in chemicals, pharmaceuticals and agrochemicals. In the work described herein, nickel(II)/Lewis acid (LA) catalysed olefin hydroamination with anilines was explored for use in aniline derivative syntheses. The Ni(II)/LA catalysis proceeded smoothly under mild conditions, whereas using Ni(OAc)2 alone, the catalyst was inactive. Remarkably, the Markovnikov addition type products were obtained when substituted styrenes were used as the olefin source, while the anti-Markovnikov addition type products were obtained when the electron-deficient olefins such as acrylonitrile and acrylates were used. The mechanistic studies revealed that hydroamination of the styrene derivates proceeded via the amino-Ni(II)/LA attacking the carbocation intermediate which was generated by the protonation of the olefin, whereas for acrylonitrile and acrylates, it proceeded by a direct amino-Ni(II)/LA attack on the olefin by nucleophilic addition. In addition, the hydroarylation product was generated by the Hofmann-Martius rearrangement of the hydroamination product.

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