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1.
Molecules ; 29(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39125046

RESUMO

Supercapacitors (SCs) are widely recognized as competitive power sources for energy storage. The hierarchical structure of nickel vanadium sulfide nanoparticles encapsulated on graphene nanosheets (NVS/G) was fabricated using a cost-effective and scalable solvothermal process. The reaction contents of the composites were explored and optimized. TEM images displayed the nickel vanadium sulfide nanoparticles (NVS NPs) with 20-30 nm average size anchored to graphene nanosheets. The interconnection of graphene nanosheets encapsulating NVS nanoparticles effectively reduces the ion diffusion path between the electrode and electrolyte, thereby enhancing electrochemical performance. The NVS/G composite demonstrated improved electrochemical performance, achieving a maximum of 1437 F g-1 specific capacitance at 1 A g-1, remarkable rate capability retaining of 1050 F g-1 at 20 A g-1, and exceptional cycle stability with 91.2% capacitance retention following 10,000 cycles. The NVS/G composite was employed as a cathode, and reduced graphene oxide (rGO) was used as an anode material to assemble a device. Importantly, asymmetric SCs using NVS/G//rGO achieved 74.7 W h kg-1 energy density at 0.8 kW kg-1 power density, along with outstanding stability with 88.2% capacitance retention following 10,000 cycles. These superior properties of the NVS/G electrode highlight its significant potential in energy storage applications.

2.
Fitoterapia ; 178: 106143, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39053740

RESUMO

Four undescribed guaiane sesquiterpenes, aquisinenoids I-L (2-5) and five known compounds were isolated from the resins of Aquilaria sinensis. Their structures were deduced based on spectroscopic data analysis, X-ray crystallography and ECD calculations. Biologically, compounds 1, 5, 6 and 9 showed anti-renal fibrosis activity, significantly reducing the levels of fibronectin, collagen I, and α-SMA. Compounds 2-4, 7 and 8 could reduce one or two of these proteins at non-toxic concentrations in TGF-ß1 induced NRK-52E cells.

3.
Nat Commun ; 15(1): 5555, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030177

RESUMO

Neurotransmitters are key modulators in neuro-immune circuits and have been linked to tumor progression. Medullary thyroid cancer (MTC), an aggressive neuroendocrine tumor, expresses neurotransmitter calcitonin gene-related peptide (CGRP), is insensitive to chemo- and radiotherapies, and the effectiveness of immunotherapies remains unknown. Thus, a comprehensive analysis of the tumor microenvironment would facilitate effective therapies and provide evidence on CGRP's function outside the nervous system. Here, we compare the single-cell landscape of MTC and papillary thyroid cancer (PTC) and find that expression of CGRP in MTC is associated with dendritic cell (DC) abnormal development characterized by activation of cAMP related pathways and high levels of Kruppel Like Factor 2 (KLF2), correlated with an impaired activity of tumor infiltrating T cells. A CGRP receptor antagonist could offset CGRP detrimental impact on DC development in vitro. Our study provides insights of the MTC immunosuppressive microenvironment, and proposes CGRP receptor as a potential therapeutic target.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Carcinoma Neuroendócrino , Células Dendríticas , Neoplasias da Glândula Tireoide , Microambiente Tumoral , Microambiente Tumoral/imunologia , Humanos , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/imunologia , Neoplasias da Glândula Tireoide/patologia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Câncer Papilífero da Tireoide/imunologia , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , AMP Cíclico/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Neurotransmissores/metabolismo , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina/farmacologia , Análise de Célula Única
4.
Phys Rev Lett ; 132(24): 243802, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949371

RESUMO

Orbital angular momentum (OAM) provides an additional degree of freedom for optical communication systems, and manipulating on-chip OAM is important in integrated photonics. However, there is no effective method to realize OAM topological charge conversion on chip. In this Letter, we propose a way to convert OAM by encircling two groups of exceptional points in different Riemann sheets. In our framework, any OAM conversion can be achieved on demand just by manipulating adiabatic and nonadiabatic evolution of modes in two on-chip waveguides. More importantly, the chiral OAM conversion is realized, which is of great significance since the path direction can determine the final topological charge order. Our Letter presents a special chiral behavior and provides a new method to manipulate OAM on the chip.

5.
Sensors (Basel) ; 24(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39001006

RESUMO

Infrared small target detection technology plays a crucial role in various fields such as military reconnaissance, power patrol, medical diagnosis, and security. The advancement of deep learning has led to the success of convolutional neural networks in target segmentation. However, due to challenges like small target scales, weak signals, and strong background interference in infrared images, convolutional neural networks often face issues like leakage and misdetection in small target segmentation tasks. To address this, an enhanced U-Net method called MST-UNet is proposed, the method combines multi-scale feature decomposition and fusion and attention mechanisms. The method involves using Haar wavelet transform instead of maximum pooling for downsampling in the encoder to minimize feature loss and enhance feature utilization. Additionally, a multi-scale residual unit is introduced to extract contextual information at different scales, improving sensory field and feature expression. The inclusion of a triple attention mechanism in the encoder structure further enhances multidimensional information utilization and feature recovery by the decoder. Experimental analysis on the NUDT-SIRST dataset demonstrates that the proposed method significantly improves target contour accuracy and segmentation precision, achieving IoU and nIoU values of 80.09% and 80.19%, respectively.

6.
Endocrine ; 85(2): 827-836, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38834859

RESUMO

PURPOSE: There is still controversy in different guidelines regarding the necessity of routine preoperative calcitonin (Ctn) testing in medullary thyroid cancer (MTC). The level of preoperative Ctn may influence the extent of surgery. METHODS: This retrospective multicenter cohort study involved 149 MTC patients from 6 centers between 2013 to 2023. Clinical characteristics, surgical procedure and clinical outcomes were compared between Ctn-screened and Non-screened group. Kaplan-Meier method was used to estimate recurrence-free survival (RFS) and overall survival (OS). RESULTS: In total, 127 MTC patients with preoperative Ctn screening and 22 MTC patients without screening were analyzed. MTC patients with preoperative Ctn screening underwent more radical surgical procedures including total thyroidectomy and lymph node dissection, compared to those without screening (84.3% vs. 68.2% and 91.3% vs. 72.7%, respectively). The rate of recurrence and death were lower in the Ctn-screened group (16.1% vs. 36.4%, 0.8% vs. 18.2%, respectively). The survival curve showed a significantly better overall survival in Ctn-screened group than Non-screened group (HR:17.932, 95% CI 1.888-170.294, p-value = 0.001), while no significant difference was observed of RFS between two groups (HR:1.6, 95% CI 0.645-3.966, p-value = 0.307). CONCLUSION: Preoperative Ctn screening can prompt surgeons choosing more radical initial surgical treatment for MTC patients, potentially leading to better long-term outcomes. Further evaluation of the cost-effectiveness of routine Ctn screening in thyroid nodule patients is warranted.


Assuntos
Calcitonina , Carcinoma Neuroendócrino , Neoplasias da Glândula Tireoide , Tireoidectomia , Humanos , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/mortalidade , Estudos Retrospectivos , Feminino , Masculino , Calcitonina/sangue , Pessoa de Meia-Idade , Carcinoma Neuroendócrino/sangue , Carcinoma Neuroendócrino/cirurgia , Carcinoma Neuroendócrino/mortalidade , Carcinoma Neuroendócrino/diagnóstico , Adulto , Prognóstico , Idoso , Cuidados Pré-Operatórios/métodos
7.
bioRxiv ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38853824

RESUMO

Recent findings indicate a correlation between the peripheral adaptive immune system and neuroinflammation in Alzheimer's disease (AD). To characterize the composition of adaptive immune cells in the peripheral blood of AD patients, we utilized single-cell mass cytometry (CyTOF) to profile peripheral blood mononuclear cells (PBMCs). Concurrently, we assessed the concentration of proteins associated with AD and neuroinflammation in the plasma of the same subjects. We found that the abundance of proinflammatory CXCR3 + CD127 + Type 1 T helper (Th1) cells in AD patients was negatively correlated with the abundance of neurofilament light chain (NfL) protein. This correlation is apolipoprotein E (ApoE) ε4-dependent. Analyzing public single-cell RNA-sequencing (scRNA-seq) data, we found that, contrary to the scenario in the peripheral blood, the cell frequency of CXCR3 + CD127 + Th1 cells in the cerebrospinal fluid (CSF) of AD patients was increased compared to healthy controls (HCs). Moreover, the proinflammatory capacity of CXCR3 + CD127 + Th1 cells in the CSF of AD patients was further increased compared to HCs. These results reveal an association of a peripheral T-cell change with neuroinflammation in AD and suggest that dysregulation of peripheral adaptive immune responses, particularly involving CXCR3 + CD127 + Th1 cells, may potentially be mediated by factors such as ApoE ε4 genotype. One sentence summary: An apolipoprotein E (ApoE) ε4-dependent alteration of CD4 T cell subpopulation in peripheral blood is associated with neuroinflammation in patients with Alzheimer's disease.

8.
ACS Nano ; 18(27): 18022-18035, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38934514

RESUMO

Precise synthesis of all-inorganic lead halide perovskite nanowire heterostructures and superlattices with designable modulation of chemical compositions is essential for tailoring their optoelectronic properties. Nevertheless, controllable synthesis of perovskite nanostructure heterostructures remains challenging and underexplored to date. Here, we report a rational strategy for wafer-scale synthesis of one-dimensional periodic CsPbCl3/CsPbI3 superlattices. We show that the highly parallel array of halide perovskite nanowires can be prepared roughly as horizontally guided growth on an M-plane sapphire. A periodic patterning of the sapphire substrate enables position-selective ion exchange to obtain highly periodic CsPbCl3/CsPbI3 nanowire superlattices. This patterning is further confirmed by micro-photoluminescence investigations, which show that two separate band-edge emission peaks appear at the interface of a CsPbCl3/CsPbI3 heterojunction. Additionally, compared with the pure CsPbCl3 nanowires, photodetectors fabricated using these periodic heterostructure nanowires exhibit superior photoelectric performance, namely, high ION/IOFF ratio (104), higher responsivity (49 A/W), and higher detectivity (1.51 × 1013 Jones). Moreover, a spatially resolved visible image sensor based on periodic nanowire superlattices is demonstrated with good imaging capability, suggesting promising application prospects in future photoelectronic imaging systems. All these results based on the periodic CsPbCl3/CsPbI3 nanowire superlattices provides an attractive material platform for integrated perovskite devices and circuits.

9.
J Alzheimers Dis ; 99(3): 1065-1075, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38788073

RESUMO

Background: Diagnostic codes can be instrumental for case identification in Alzheimer's disease (AD) research; however, this method has known limitations and cannot distinguish between disease stages. Clinical notes may offer more detailed information including AD severity and can complement diagnostic codes for case identification. Objective: To estimate prevalence of mild cognitive impairment (MCI) and AD using diagnostics codes and clinical notes available in the electronic healthcare record (EHR). Methods: This was a retrospective study in the Veterans Affairs Healthcare System (VAHS). Health records from Veterans aged 65 years or older were reviewed during Fiscal Years (FY) 2010-2019. Overall, 274,736 and 469,569 Veterans were identified based on a rule-based algorithm as having at least one clinical note for MCI and AD, respectively; 201,211 and 149,779 Veterans had a diagnostic code for MCI and AD, respectively. During FY 2011-2018, likely MCI or AD diagnosis was defined by≥2 qualifiers (i.e., notes and/or codes)≥30 days apart. Veterans with only 1 qualifier were considered as suspected MCI/AD. Results: Over the 8-year study, 147,106 and 207,225 Veterans had likely MCI and AD, respectively. From 2011 to 2018, yearly MCI prevalence increased from 0.9% to 2.2%; yearly AD prevalence slightly decreased from 2.4% to 2.1%; mild AD changed from 22.9% to 26.8%, moderate AD changed from 26.5% to 29.1%, and severe AD changed from 24.6% to 30.7. Conclusions: The relative distribution of AD severities was stable over time. Accurate prevalence estimation is critical for healthcare resource allocation and facilitating patients receiving innovative medicines.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Veteranos , Humanos , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/diagnóstico , Estados Unidos/epidemiologia , Idoso , Masculino , Feminino , Prevalência , Veteranos/estatística & dados numéricos , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Registros Eletrônicos de Saúde , United States Department of Veterans Affairs
10.
Materials (Basel) ; 17(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38793377

RESUMO

Hot-rolled backup rolls are widely used in steel rolling and usually need to be repaired by arc hardfacing after becoming worn. However, a corrugated-groove defect commonly occurs on the roll surface due to the uneven hardness distribution in the hardfacing layers, affecting the proper usage of the roll. Accordingly, a new swing-arc submerged arc welding (SA-SAW) process is proposed to attempt to solve this drawback. The microstructure and hardness are then investigated experimentally for both SAW and SA-SAW hardfacing layers. It is revealed that a self-tempering effect occurs in the welding pass bottom and the welding pass side neighboring the former pass for both processes, refining the grain in the two areas. In all the zones, including the self-tempering zone (STZ), heat-affected zone (HAZ), and not-heat-affected zone in the welding pass, both SAW and SA-SAW passes crystallize in a type of columnar grain, where the grains are the finest in STZ and the coarsest in HAZ. In addition, the arc swing improves the microstructure homogeneity of the hardfacing layers by obviously lowering the tempering degree in HAZ while promoting the even distribution of the arc heat. Accordingly, the hardness of the SA-SAW bead overall increases and distributes more uniformly with a maximum difference of < 80 HV0.5 along the horizontal direction of the bead. This hardness difference in SA-SAW is accordingly decreased by ~38.5% compared to that of the SAW bead, further indicating the practicability of the new process.

11.
IEEE Trans Pattern Anal Mach Intell ; 46(8): 5227-5244, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38568772

RESUMO

The foundation model has recently garnered significant attention due to its potential to revolutionize the field of visual representation learning in a self-supervised manner. While most foundation models are tailored to effectively process RGB images for various visual tasks, there is a noticeable gap in research focused on spectral data, which offers valuable information for scene understanding, especially in remote sensing (RS) applications. To fill this gap, we created for the first time a universal RS foundation model, named SpectralGPT, which is purpose-built to handle spectral RS images using a novel 3D generative pretrained transformer (GPT). Compared to existing foundation models, SpectralGPT 1) accommodates input images with varying sizes, resolutions, time series, and regions in a progressive training fashion, enabling full utilization of extensive RS Big Data; 2) leverages 3D token generation for spatial-spectral coupling; 3) captures spectrally sequential patterns via multi-target reconstruction; and 4) trains on one million spectral RS images, yielding models with over 600 million parameters. Our evaluation highlights significant performance improvements with pretrained SpectralGPT models, signifying substantial potential in advancing spectral RS Big Data applications within the field of geoscience across four downstream tasks: single/multi-label scene classification, semantic segmentation, and change detection.

12.
Diabetes Metab Syndr Obes ; 17: 1289-1299, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505538

RESUMO

Diabetic nephropathy (DN) is one of the most common microvascular complications in diabetes and can potentially develop into end-stage renal disease. Its pathogenesis is complex and not fully understood. Podocytes, glomerular endothelial cells (GECs), glomerular mesangial cells (GMCs) and renal tubular epithelial cells (TECs) play important roles in the normal function of glomerulus and renal tubules, and their injury is involved in the progression of DN. Although our understanding of the mechanisms leading to DN has substantially improved, we still need to find more effective therapeutic targets. Autophagy, pyroptosis and ferroptosis are programmed cell death processes that are associated with inflammation and are closely related to a variety of diseases. Recently, a growing number of studies have reported that autophagy, pyroptosis and ferroptosis regulate the function of podocytes, GECs, GMCs and TECs. This review highlights the contributions of autophagy, pyroptosis, and ferroptosis to DN injury in these cells, offering potential therapeutic targets for DN treatment.

13.
Front Pharmacol ; 15: 1268464, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464713

RESUMO

Scopoletin is a coumarin synthesized by diverse medicinal and edible plants, which plays a vital role as a therapeutic and chemopreventive agent in the treatment of a variety of diseases. In this review, an overview of the pharmacology, pharmacokinetics, and toxicity of scopoletin is provided. In addition, the prospects and outlook for future studies are appraised. Scopoletin is indicated to have antimicrobial, anticancer, anti-inflammation, anti-angiogenesis, anti-oxidation, antidiabetic, antihypertensive, hepatoprotective, and neuroprotective properties and immunomodulatory effects in both in vitro and in vivo experimental trials. In addition, it is an inhibitor of various enzymes, including choline acetyltransferase, acetylcholinesterase, and monoamine oxidase. Pharmacokinetic studies have demonstrated the low bioavailability, rapid absorption, and extensive metabolism of scopoletin. These properties may be associated with its poor solubility in aqueous media. In addition, toxicity research indicates the non-toxicity of scopoletin to most cell types tested to date, suggesting that scopoletin will neither induce treatment-associated mortality nor abnormal performance with the test dose. Considering its favorable pharmacological activities, scopoletin has the potential to act as a drug candidate in the treatment of cancer, liver disease, diabetes, neurodegenerative disease, and mental disorders. In view of its merits and limitations, scopoletin is a suitable lead compound for the development of new, efficient, and low-toxicity derivatives. Additional studies are needed to explore its molecular mechanisms and targets, verify its toxicity, and promote its oral bioavailability.

14.
Neural Plast ; 2024: 5599046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529366

RESUMO

Low back pain (LBP) is a leading cause of global disabilities. Numerous molecular, cellular, and anatomical factors are implicated in LBP. Current issues regarding neurologic alterations in LBP have focused on the reorganization of peripheral nerve and spinal cord, but neural mechanisms of exactly what LBP impacts on the brain required further researches. Based on existing clinical studies that chronic pain problems were accompanying alterations in brain structures and functions, researchers proposed logical conjectures that similar alterations occur in LBP patients as well. With recent extensive studies carried out using noninvasive neuroimaging technique, increasing number of abnormalities and alterations has been identified. Here, we reviewed brain alterations including white matters, grey matters, and neural circuits between brain areas, which are involved in chronic LBP. Moreover, brain structural and functional connectivity abnormalities are correlated to the happening and transition of LBP. The negative emotions related to back pain indicate possible alterations in emotional brain regions. Thus, the aim of this review is to summarize current findings on the alterations corresponding to LBP in the brain. It will not only further our understanding of etiology of LBP and understanding of negative emotions accompanying with back pain but also provide ideas and basis for new accesses to the diagnosis, treatment, and rehabilitation afterward based on integral medicine.


Assuntos
Dor Lombar , Humanos , Encéfalo/diagnóstico por imagem , Emoções , Medula Espinal
15.
Int Immunopharmacol ; 130: 111755, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38408417

RESUMO

A growing amount of epidemiological evidence proposes diabetes mellitus (DM) to be an independent risk factor for osteoarthritis (OA). Sirtuin 3 (SIRT3), which is mainly located in mitochondria, belongs to the family of nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylases and is involved in the physiological and pathological processes of cell regulation. The aim of this study was to investigate the effects of SIRT3 on diabetic OA and underlying mechanisms in the prevention of type 2 DM (T2DM)-induced articular cartilage damage. High-fat and high-sugar diets combined with streptozotocin (STZ) injection were used for establishing an experimental T2DM rat model. The destabilization of medial meniscus (DMM) surgery was applied to induce the rat OA model. Primary rat chondrocytes were cultivated with a concentration of gradient glucose. Treatment with intra-articular injection of SIRT3 overexpression lentivirus was achieved in vivo, and intervention with SIRT3 knockdown was performed using siRNA transfection in vitro. High glucose content was found to activate inflammatory response, facilitate apoptosis, downregulate autophagy, and exacerbate mitochondrial dysfunction in a dose-dependent manner in rat chondrocytes, which can be deteriorated by SIRT3 knockdown. In addition, articular cartilage damage was found to be more severe in T2DM-OA rats than in DMM-induced OA rats, which can be mitigated by the intra-articular injection of SIRT3 overexpression lentivirus. Targeting SIRT3 is a potential therapeutic strategy for the alleviation of diabetic OA.


Assuntos
Condrócitos , Osteoartrite , Sirtuína 3 , Animais , Ratos , Apoptose , Autofagia , Cartilagem Articular/patologia , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Osteoartrite/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo
16.
Front Public Health ; 12: 1295433, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371232

RESUMO

Background: One of the biggest challenges facing older adults is cognitive decline and social participation has always been considered a protective factor. However, it is not clear whether social participation predicts cognitive function in this population, rather than depressive symptoms, self-reported health, and activities of daily life, with sufficient capacity to detect unique effects. Methods: This study included adults aged 45 and above in China (N = 5,258) who participated in a large national older adult health survey and provided data from 2011, 2013, 2015, and 2018. The unique associations between the predictors of social participation and cognitive function over time and context were evaluated in the Latent Growth Model (LGM). Results: Among the 5,258 participants in our study, an overall cognitive decline was observed. Social participation predicts two dimensions of cognitive function, with a degree of impact comparable to depressive symptoms, self-reported health, and activities of daily life. Among them, social participation exhibits a noteworthy prognostic impact on episodic memory during the same period. The regression coefficient is approximately 0.1 (p < 0.05) after controlling other mixed variables (depressive symptoms, self-reported health, and activities of daily life). In contrast, social participation is also a significant predictor of mental intactness in the same period, with a regression coefficient of 0.06 (p < 0.05), even if all mixed variables are controlled. Conclusion: Over time, the correlation strength of social participation is comparable to other recognized cognitive function prediction indicators, indicating that promoting social participation among middle-aged and older Chinese adults is a meaningful way to improve cognitive function degradation, which has important policy and practical significance.


Assuntos
Disfunção Cognitiva , Participação Social , Pessoa de Meia-Idade , Humanos , Idoso , Participação Social/psicologia , Estudos Longitudinais , Envelhecimento/psicologia , Cognição , Disfunção Cognitiva/epidemiologia
17.
Angew Chem Int Ed Engl ; 63(12): e202318784, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38291557

RESUMO

Plitidepsin (or dehydrodidemnin B), an approved anticancer drug, belongs to the didemnin family of cyclic depsipeptides, which are found in limited quantities in marine tunicate extracts. Herein, we introduce a new approach that integrates microbial and chemical synthesis to generate plitidepsin and its analogues. We screened a Tistrella strain library to identify a potent didemnin B producer, and then introduced a second copy of the didemnin biosynthetic gene cluster into its genome, resulting in a didemnin B titer of approximately 75 mg/L. Next, we developed two straightforward chemical strategies to convert didemnin B into plitidepsin, one of which involved a one-step synthetic route giving over 90 % overall yield. Furthermore, we synthesized 13 new didemnin derivatives and three didemnin probes, enabling research into structure-activity relationships and interactions between didemnin and proteins. Our study highlights the synergistic potential of biosynthesis and chemical synthesis in overcoming the challenge of producing complex natural products sustainably and at scale.


Assuntos
Antineoplásicos , Depsipeptídeos , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/metabolismo , Depsipeptídeos/farmacologia , Antineoplásicos/farmacologia , Relação Estrutura-Atividade
19.
Endocrine ; 84(2): 646-655, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38175390

RESUMO

PURPOSE: Accurate preoperative diagnosis of lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) remains an unsolved problem. This study aimed to construct a nomogram and scoring system for predicting LNM based on the clinical characteristics of patients with PTC. METHODS: 1400 patients with PTC who underwent thyroidectomy and lymph node dissection at the First Affiliated Hospital of Sun Yat-sen University were retrospectively enrolled and randomly divided into training and internal testing sets. Furthermore, 692 patients with PTC from three other medical centers were collected as external testing sets. Least absolute shrinkage and selection operator (LASSO) was used to screen the predictors, and a nomogram was constructed. In addition, a scoring system was constructed using 10-fold cross-validation. The performances of the two models were verified among datasets and compared with preoperative ultrasound (US). RESULTS: Six independent predictors were included in the multivariate logistic model: age, sex, US diagnosis of LNM, tumor diameter, location, and thyroid peroxidase antibody level. The areas under the receiver operating characteristic curve (AUROC) (95% confidence interval) of this nomogram in the training, internal testing, and three external testing sets were 0.816 (0.791-0.840), 0.782 (0.727-0.837), 0.759 (0.699-0.819), 0.749 (0.667-0.831), and 0.777 (0.726-0.828), respectively. The AUROC of the scoring system were 0.810 (0.785-0.835), 0.772 (0.718-0.826), 0.736 (0.675-0.798), 0.717 (0.635-0.799) and 0.756 (0.704-0.808), respectively. The prediction performances were both significantly superior to those of preoperative US (P < 0.001). CONCLUSION: The nomogram and scoring system performed well in different datasets and significantly improved the preoperative prediction of LNM than US alone.


Assuntos
Metástase Linfática , Nomogramas , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Feminino , Masculino , Metástase Linfática/patologia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Pessoa de Meia-Idade , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/cirurgia , Adulto , Estudos Retrospectivos , Linfonodos/patologia , Tireoidectomia , Pescoço/patologia , Adulto Jovem , Idoso , Excisão de Linfonodo
20.
Chem Biol Interact ; 390: 110890, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38278314

RESUMO

Osteoarthritis (OA) is the most common type of arthritis and is an age-related joint disease that is particularly prevalent in subjects over 65 years old. The chronic rise of senescent cells has a close correlation with age-related diseases such as OA, and the senescence-associated secretory phenotype (SASP) is implicated in OA cartilage degeneration pathogenesis. Sirtuin 6 (SIRT6) is likely to be a key senescence-related regulator. Fisetin (FST) is a natural flavonol of the flavonoid family that is recommended as a senolytic drug to extend health and lifespan. However, the potential chondroprotective effects of FST on OA rats are largely unclarified. The aim of this study is to investigate the ameliorative effects of FST on OA joint cartilage and the relationship with SIRT6 and the detailed mechanisms from anti-inflammatory and anti-senescent perspectives. Rats were subjected to destabilization of the medial meniscus (DMM) surgery as a means of inducing the experimental OA model in vivo. Chondrocytes treated with IL-1ß were utilized for mimicking the OA cell model in vitro. Intra-articular injection of FST, OSS_128,167 (OSS, SIRT6 inhibitor), and MDL800 (MDL, SIRT6 agonist) in vivo or administering them in IL-1ß-induced rat chondrocytes in vitro were performed in order to determine the effects FST has on OA and the link with SIRT6. This study found SIRT6 level to be negatively correlated with OA severity. SIRT6 downregulation was validated in the joint cartilages of DMM rats and IL-1ß-treated chondrocytes. It was also notably demonstrated that FST can activate SIRT6. Both the administration of FST and activation of SIRT6 using MDL were found to rescue cartilage erosion, decrease extracellular matrix (ECM) degradation, prevent cartilage from apoptosis, and improve detrimental senescence-related phenotype. The alleviative effects of FST against inflammation, ECM degradation, apoptosis, and senescence in IL-1ß-stimulated chondrocytes were also confirmed. SIRT6 loss occurs in articular cartilage in OA pathogenesis, which is linked to aging. FST attenuates injury-induced aging-related phenotype changes in chondrocytes through the targeting of SIRT6.


Assuntos
Cartilagem Articular , Osteoartrite , Sirtuínas , Humanos , Ratos , Animais , Idoso , Condrócitos , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Flavonóis/farmacologia , Flavonóis/metabolismo , Interleucina-1beta/metabolismo , Cartilagem Articular/metabolismo , Sirtuínas/metabolismo , Senescência Celular
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