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1.
Toxicol Appl Pharmacol ; 487: 116957, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38735590

RESUMEN

Heart failure is associated with histone deacetylase (HDAC) regulation of gene expression, the inhibition of which is thought to be beneficial for heart failure therapy. Here, we explored the cardioprotective effects and underlying mechanism of a novel selenium-containing HDAC inhibitor, Se-SAHA, on isoproterenol (ISO)-induced heart failure. We found that pretreatment with Se-SAHA attenuated ISO-induced cardiac hypertrophy and fibrosis in neonatal rat ventricular myocytes (NRVMs). Se-SAHA significantly attenuated the generation of ISO-induced reactive oxygen species (ROS) and restored the expression levels of superoxide dismutase 2 (SOD2) and heme oxygenase-1 (HO-1) in vitro. Furthermore, Se-SAHA pretreatment prevented the accumulation of autophagosomes. Se-SAHA reversed the high expression of HDAC1 and HDAC6 induced by ISO incubation. However, after the addition of the HDAC agonist, the effect of Se-SAHA on blocking autophagy was inhibited. Using ISO-induced mouse models, cardiac ventricular contractile dysfunction, hypertrophy, and fibrosis was reduced treated by Se-SAHA. In addition, Se-SAHA inhibited HDAC1 and HDAC6 overexpression in ISO-treated mice. Se-SAHA treatment significantly increased the activity of SOD2 and improved the ability to eliminate free radicals. Se-SAHA hindered the excessive levels of the microtubule-associated protein 1 light chain 3 (LC3)-II and Beclin-1 in heart failure mice. Collectively, our results indicate that Se-SAHA exerts cardio-protection against ISO-induced heart failure via antioxidative stress and autophagy inhibition.


Asunto(s)
Autofagia , Insuficiencia Cardíaca , Inhibidores de Histona Desacetilasas , Isoproterenol , Ratones Endogámicos C57BL , Miocitos Cardíacos , Estrés Oxidativo , Ratas Sprague-Dawley , Animales , Isoproterenol/toxicidad , Insuficiencia Cardíaca/inducido químicamente , Insuficiencia Cardíaca/prevención & control , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/tratamiento farmacológico , Autofagia/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Estrés Oxidativo/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Miocitos Cardíacos/metabolismo , Masculino , Ratas , Ratones , Superóxido Dismutasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Antioxidantes/farmacología , Fibrosis , Células Cultivadas , Cardiomegalia/inducido químicamente , Cardiomegalia/prevención & control , Cardiomegalia/patología
2.
Bioorg Chem ; 150: 107532, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38852312

RESUMEN

Staphylococcus aureus is considered to be an extracellular pathogen. However, survival of S.aureus within host cells may cause long-term colonization and clinical failure. Current treatments have poor efficacy in clearing intracellular bacteria. Antibody-antibiotic conjugates (AACs) is a novel strategy for eliminating intracellular bacteria. Herein, we use KRM-1657 as payload of AAC for the first time, and we conjugate it with anti S. aureus antibody via a dipeptide linker (Valine-Alanine) to obtain a novel AAC (ASAK-22). The ASAK-22 exhibits good in vitro pharmacokinetic properties and inhibitory activity against intracellular MRSA, with 100 µg/mL of ASAK-22 capable of eliminating intracellular MRSA to the detection limit. Furthermore, the in vivo results demonstrate that a single administration of ASAK-22 significantly reduces the bacterial burden in the bacteremia model, which is superior to the vancomycin treatment.

3.
Pediatr Cardiol ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809278

RESUMEN

Current study aims to compare the application of two-dimensional (2D) color doppler ultrasound (CDU) and four-dimensional (4D) ultrasound spatiotemporal image correlation (STIC) in fetal congenital heart disease in the second trimester of pregnancy and to analyze the high risk factors of the disease. From August 2019 to July 2021, 135 second-trimester patients with highly suspected congenital heart malformations were selected who underwent prenatal screening at South Taihu Hospital Affiliated to Huzhou University. 2D-CDU, 4D STIC, and postnatal examination were completed in all patients. 2D-CDU, 4D STIC and 2D-CDU combined with 4D STIC were used to detect fetal cardiac malformations and classify cardiac malformations. The sensitivity, specificity, positive predictive value, negative predictive value and coincidence rate of 2D-CDU, 4D STIC and 2D-CDU combined with 4D STIC were compared. The results of 2D-CDU, 4D STIC and 2D-CDU combined with 4D STIC screening were analyzed for consistency using the results of postpartum diagnosis as the gold standard. Moreover, effects of maternal gestational factors on fetal cardiac malformations by univariate and multivariate analysis. 2D-CDU combined with 4D STIC showed significantly higher section display number than 2D-CDU or 4D STIC in the view of ductal arch, aortic arch, and aortic short-axis. A total of 45 cases of fetal congenital heart malformation were detected in 135 patients in the second trimester, 40, 38 or 42 cases were detected by 2D-CDU, 4D STIC or 2D-CDU combined with 4D STIC, respectively. The sensitivity, specificity, positive predictive value, negative predictive value and coincidence rate of 2D-CDU combined with 4D ultrasound in congenital heart malformation screening were higher than those of 2D-CDU or 4D STIC. Kappa agreement analysis showed that the diagnostic results of 4D STIC and 2D-CDU combined with 4D ultrasound in fetuses with suspected congenital heart malformation were in excellent agreement (κ > 0.75), while 2D-CDU was in good agreement with postpartum diagnosis (κ < 0.75). Univariate and multivariate regression analysis revealed that maternal age ≥ 35, drinking during pregnancy, and history of adverse pregnancy and childbirth were all independent risk factors for fetal cardiac malformations, while folic acid supplementation was an independent protective factor for fetal cardiac malformations. 2D-CDU combined with 4D echocardiography may be superior to single 2D-CDU or 4D STIC in the screening of fetal congenital heart malformation in the second trimester. In order to reduce the incidence of fetal heart anomalies, we should strengthen the screening of pregnancy anomalies in high-risk pregnant women and control the risk factors.

4.
Angew Chem Int Ed Engl ; 63(18): e202402202, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38375743

RESUMEN

Poly(ethylene oxide) (PEO)-based electrolytes are often used for Li+ conduction as they can dissociate the Li salts efficiently. However, high entanglement of the chains and lack of pathways for rapid ion diffusion limit their applications in advanced batteries. Recent developments in ionic covalent organic frameworks (iCOFs) showed that their highly ordered structures provide efficient pathways for Li+ transport, solving the limitations of traditional PEO-based electrolytes. Here, we present imidazolate COFs, PI-TMEFB-COFs, having methoxyethoxy chains, synthesized by Debus-Radziszewski multicomponent reactions and their ionized form, Li+@PI-TMEFB-COFs, showing a high Li+ conductivity of 8.81 mS cm-1 and a transference number of 0.974. The mechanism for such excellent electrochemical properties is that methoxyethoxy chains dissociate LiClO4, making free Li+, then those Li+ are transported through the imidazolate COFs' pores. The synthesized Li+@PI-TMEFB-COFs formed a stable interface with Li metal. Thus, employing Li+@PI-TMEFB-COFs as the solid electrolyte to assemble LiFePO4 batteries showed an initial discharge capacity of 119.2 mAh g-1 at 0.5 C, and 82.0 % capacity and 99.9 % Coulombic efficiency were maintained after 400 cycles. These results show that iCOFs with ether chains synthesized via multicomponent reactions can create a new chapter for making solid electrolytes for advanced rechargeable batteries.

5.
Angew Chem Int Ed Engl ; 63(16): e202310318, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38369681

RESUMEN

Existing antibody-drug conjugate (ADC) linkers, whether cleavable or non-cleavable, are designed to release highly toxic payloads or payload derivatives upon internalisation of the ADCs into cells. However, clinical studies have shown that only <1 % of the dosed ADCs accumulate in tumour cells. The remaining >99 % of ADCs are nonspecifically distributed in healthy tissue cells, thus inevitably leading to off-target toxicity. Herein, we describe an intelligent tumour-specific linker strategy to address these limitations. A tumour-specific linker is constructed by introducing a hypoxia-activated azobenzene group as a toxicity controller. We show that this azobenzene-based linker is non-cleavable in healthy tissues (O2 >10 %), and the corresponding payload derivative, cysteine-appended azobenzene-linker-monomethyl auristatin E (MMAE), can serve as a safe prodrug to mask the toxicity of MMAE (switched off). Upon exposure to the hypoxic tumour microenvironment (O2<1 %), this linker is cleaved to release MMAE and fully restores the high cytotoxicity of the ADC (switched on). Notably, the azobenzene linker-containing ADC exhibits satisfactory antitumour efficacy in vivo and a larger therapeutic window compared with ADCs containing traditional cleavable or non-cleavable linkers. Thus, our azobenzene-based linker sheds new light on the development of next-generation ADC linkers.


Asunto(s)
Antineoplásicos , Inmunoconjugados , Neoplasias , Humanos , Antineoplásicos/farmacología , Compuestos Azo , Línea Celular Tumoral , Microambiente Tumoral
6.
Neuroimage ; 269: 119916, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36736638

RESUMEN

There is growing evidence that blood-oxygen-level-dependent (BOLD) activity in the white matter (WM) can be detected by functional magnetic resonance imaging (fMRI). However, the functional relevance and significance of WM BOLD signals remain controversial. Here we investigated whether 7T BOLD fMRI can reveal fine-scale functional organizations of a WM bundle. Population receptive field (pRF) analyses of the 7T retinotopy dataset from the Human Connectome Project revealed clear contralateral retinotopic organizations of two visual WM bundles: the optic radiation (OR) and the vertical occipital fasciculus (VOF). The retinotopic maps of OR are highly consistent with post-mortem dissections and diffusion tractographies, while the VOF maps are compatible with the dorsal and ventral visual areas connected by the WM. Similar to the grey matter (GM) visual areas, both WM bundles show over-representations of the central visual field and increasing pRF size with eccentricity. Hemodynamic response functions of visual WM were slower and wider compared with those of GM areas. These findings clearly demonstrate that WM BOLD at 7 Tesla is closely coupled with neural activity related to axons, encoding highly specific information that can be used to characterize fine-scale functional organizations of a WM bundle.


Asunto(s)
Sustancia Blanca , Humanos , Sustancia Blanca/fisiología , Campos Visuales , Imagen por Resonancia Magnética , Imagen de Difusión Tensora/métodos , Sustancia Gris
7.
J Am Chem Soc ; 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37916601

RESUMEN

Lithium (Li)-metal batteries (LMBs) possess the highest theoretical energy density among current battery designs and thus have enormous potential for use in energy storage. However, the development of LMBs has been severely hindered by safety concerns arising from dendrite growth and unstable interphases on the Li anode. Covalent organic frameworks (COFs) incorporating either redox-active or anionic moieties on their backbones have high Li-ion (Li+) conductivities and mechanical/chemical stabilities, so are promising for solid electrolyte interphases (SEIs) in LMBs. Here, we synthesized anthraquinone-based silicate COFs (AQ-Si-COFs) that contained both redox-active and anionic sites via condensation of tetrahydroxyanthraquinone with silicon dioxide. The nine Li+-mediated charge/discharge processes enabled the AQ-Si-COF to demonstrate an ionic conductivity of 9.8 mS cm-1 at room temperature and a single-ion-conductive transference number of 0.92. Computational studies also supported the nine Li+ mechanism. We used AQ-Si-COF as the solid electrolyte interphase on the Li anode. The LMB cells with a LiCoO2 cathode attained a maximum reversible capacity of 188 mAh g-1 at 0.25 C during high-voltage operation. Moreover, this LMB cell demonstrated suppressed dendrite growth and stable cyclability, with its capacity decreasing by less than 3% up to 100 cycles. These findings demonstrate the effectiveness of our redox-active and anionic COFs and their practical utility as SEI in LMB.

8.
Prostate ; 83(5): 470-486, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36576015

RESUMEN

BACKGROUND: Like DNA methylation, histone modifications are considered important processes for epigenetic alterations in gene function, and abnormally high expression of histone deacetylases (HDACs) plays a key role in many human diseases. In addition to regulating the acetylation levels of histone and non-histone proteins and gene transcription, HDAC inhibitors as antitumor drugs can also affect the DNA damage repair (DDR) pathway in tumor cells. Prostate cancer (PCa) is one of the most heritable malignancies in which DDR pathway defects can be detected in a considerable proportion of cases. Such defects are more prevalent in castration-resistant prostate cancer (CRPC) and are highly enriched in metastatic lesions. There is currently evidence that DDR pathway-deficient PCa is associated with high-risk biological behaviors and response sensitivity to platinum-based chemotherapy. Platinum-based drugs have been used in multiple clinical trials as monotherapy or in combination with other chemotherapeutic agents for the treatment of CRPC. METHODS: This study evaluated the combined anticancer effect of (cisplatin) CDDP and the HDAC inhibitors vorinostat (SAHA) on three androgen-dependent cell lines PC-3, DU-145, and C4-2B in vitro. The efficacy and safety of SAHA combined with CDDP in the treatment of CRPC were further verified through animal experiments. RESULTS: The combination of the two drugs increases cytotoxic effects by increasing DNA damage. Our results showed that the SAHA could not only reduce the expression of homologous recombinant repair proteins BRCA2, BRCA1, PARP1, and RAD51, but also decrease enzymes that Reduce the key enzymes of GSH biosynthesis, GSS and GCLC, and GSTP1 which can catalyze the binding of GSH to cisplatin. The intracellular GSH level also decreased with the increase of SAHA concentration, at the same time, the content of intracellular Pt element. CONCLUSION: The combination of CDDP and SAHA can produce synergistic anticancer effects in androgen-independent PCa cells in vitro and in vivo. Our results open up a new avenue for the effective treatment of CRPC. To optimize the chemotherapy regimen for patients with advanced PCa, it is necessary to further study the molecular mechanism of platinum drugs, HDAC inhibitors, and their combined action.


Asunto(s)
Antineoplásicos , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Animales , Humanos , Vorinostat/farmacología , Cisplatino , Inhibidores de Histona Desacetilasas/farmacología , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Andrógenos , Línea Celular Tumoral , Antineoplásicos/farmacología , Daño del ADN
9.
Phytother Res ; 37(10): 4655-4673, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37525965

RESUMEN

The worldwide overall 5-year survival rate of esophageal squamous cell carcinoma (ESCC) patients is less than 20%, and novel therapeutic strategies for these patients are urgently needed. Harmine is a natural ß-carboline alkaloid, which received great interest in cancer research because of its biological and anti-tumor activities. The aim of this study is to examine the effects of harmine on ESCC and its mechanism. We investigated the effects of harmine on proliferation, cell cycle, apoptosis, and tumor growth in vivo. RNA sequencing (RNA-seq), real-time PCR, and western blotting were used to detect the mechanism. Harmine inhibited ESCC cell growth in vitro and tumor growth in vivo. Differentially expressed genes in harmine-treated ESCC cells were mainly involved in protein processing in the endoplasmic reticulum (ER). Real-time PCR and western blotting confirmed harmine-induced cellular ER stress. CRISPR-Cas9 knockout of C/EBP homologous protein (CHOP) abolished harmine-induced expression of death receptor 5 and apoptosis. Harmine also induced the expression of CHOP-mediated sestrin-2, which in turn contributes to autophagosome formation via suppressing the AMP-activated protein kinase-protein kinase B-mammalian target of rapamycin signaling pathway. In conclusion, our results demonstrate that harmine inhibits the growth of ESCC through its regulation of ER stress, suggesting that it is a promising candidate for ESCC treatment.

10.
Drug Dev Ind Pharm ; 49(2): 232-239, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37039088

RESUMEN

OBJECTIVE: Pulmonary aspergillosis, which is a secondary complication of fungal pneumonia, is widely considered to have an increasing incidence and high mortality. Itraconazole (Itz) can inhibit ergosterol biosynthesis to treat pulmonary aspergillosis. Nevereless, Itz's clinical application is limited because of its poor water solubility, low oral bioavailability, and systemic hepatotoxicity. In this study, Itz-loaded nanostructured lipid carriers (Itz-NLCs) were developed to improve the in vitro permeability and bioavailability of Itz via pulmonary administration. METHODS: Itz-NLCs were prepared by the emulsification-evaporation method using oleic acid and glycerol monostearate as liquid and solid lipids, respectively. RESULTS: The Itz-NLCs were optimized with tiny particle size, uniform distribution, and excellent entrapment efficiency (EE, 97.57% ± 0.45%). A Xenopus alveolar membrane was used in the permeation study, and the cumulative permeation percentage of Itz was 10% for Itz-NLCs at 8 h, which was 2.50-fold higher than that for Itz suspensions (4%, p < .001). A rabbit pharmacokinetic investigation revealed that Itz-NLCs have an 83.05% absolute bioavailability after intratracheal instillation. CONCLUSIONS: The purpose of Itz-NLCs is to enhance the bioavailability and permeability of Itz in vitro for administration via the lungs.


Asunto(s)
Nanoestructuras , Aspergilosis Pulmonar , Animales , Conejos , Itraconazol/farmacología , Portadores de Fármacos , Administración Oral , Lípidos , Disponibilidad Biológica , Tamaño de la Partícula
11.
Int J Mol Sci ; 24(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36835603

RESUMEN

Exhaustion of chimeric antigen receptor (CAR) T cells is one of the limitations for CAR T efficacy in solid tumors and for tumor recurrence after initial CAR T treatment. Tumor treatment with a combination of programmed cell death receptor-1 (PD-1)/programmed cell death ligand-1 (PD-L1) blockage and CD28-based CAR T cells has been intensively studied. However, it remains largely unclear whether autocrine single-chain variable fragments (scFv) PD-L1 antibody can improve 4-1BB-based CAR T cell anti-tumor activity and revert CAR T cell exhaustion. Here, we studied T cells engineered with autocrine PD-L1 scFv and 4-1BB-containing CAR. The antitumor activity and exhaustion of CAR T cells were investigated in vitro and in a xenograft cancer model using NCG mice. CAR T cells with autocrine PD-L1 scFv antibody demonstrate enhanced anti-tumor activity in solid tumors and hematologic malignancies by blocking the PD-1/PD-L1 signaling. Importantly, we found that CAR T exhaustion was largely diminished by autocrine PD-L1 scFv antibody in vivo. As such, 4-1BB CAR T with autocrine PD-L1 scFv antibody combined the power of CAR T cells and the immune checkpoint inhibitor, thereby increasing the anti-tumor immune function and CAR T persistence, providing a cell therapy solution for a better clinical outcome.


Asunto(s)
Receptores Quiméricos de Antígenos , Anticuerpos de Cadena Única , Humanos , Animales , Ratones , Receptores de Antígenos de Linfocitos T/metabolismo , Antígeno B7-H1/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Línea Celular Tumoral , Recurrencia Local de Neoplasia/metabolismo , Linfocitos T , Inmunidad
12.
Neuroimage ; 264: 119772, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36436711

RESUMEN

Multiple sclerosis (MS) is an inflammatory demyelinating disease. Current treatments are focussed on immune suppression to modulate pathogenic activity that causes myelin damage. New treatment strategies are needed to prevent demyelination and promote remyelination. Development of such myelin repair therapies require a sensitive and specific biomarker for efficacy evaluation. Recently, it has been shown that quantification of myelin density is possible using [11C]MeDAS PET. This method, however, requires arterial blood sampling to generate an arterial input function (AIF). As the invasive nature of arterial sampling will reduce clinical applicability, the purpose of this study was to assess whether an image-derived input function (IDIF) can be used as an alternative way to facilitate its routine clinical use. Six healthy controls and 11 MS patients underwent MRI and [11C]MeDAS PET with arterial blood sampling. The application of both population-based whole blood-to-plasma conversion and metabolite corrections were assessed for the AIF. Next, summed images of the early time frames (0-70 s) and the frame with the highest blood-brain contrast were used to generate IDIFs. IDIFs were created using either the hottest 2, 4, 6 or 12 voxels, or an isocontour of the hottest 10% voxels of the carotid artery. This was followed by blood-to-plasma conversion and metabolite correction of the IDIF. The application of a population-based metabolite correction of the AIF resulted in high correlations of tracer binding (Ki) within subjects, but variable bias across subjects. All IDIFs had a sharper and higher peak in the blood curves than the AIF, most likely due to dispersion during blood sampling. All IDIF methods resulted in similar high correlations within subjects (r = 0.95-0.98), but highly variable bias across subjects (mean slope=0.90-1.09). Therefore, both the use of population based blood-plasma and metabolite corrections and the generation of the image-derived whole-blood curve resulted in substantial bias in [11C]MeDAS PET quantification, due to high inter-subject variability. Consequently, when unbiased quantification of [11C]MeDAS PET data is required, individual AIF needs to be used.


Asunto(s)
Esclerosis Múltiple , Tomografía de Emisión de Positrones , Humanos , Tomografía de Emisión de Positrones/métodos , Vaina de Mielina , Algoritmos , Imagen por Resonancia Magnética , Arterias , Esclerosis Múltiple/diagnóstico por imagen
13.
Hum Brain Mapp ; 43(8): 2683-2692, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35212436

RESUMEN

Decoding brain cognitive states from neuroimaging signals is an important topic in neuroscience. In recent years, deep neural networks (DNNs) have been recruited for multiple brain state decoding and achieved good performance. However, the open question of how to interpret the DNN black box remains unanswered. Capitalizing on advances in machine learning, we integrated attention modules into brain decoders to facilitate an in-depth interpretation of DNN channels. A four-dimensional (4D) convolution operation was also included to extract temporo-spatial interaction within the fMRI signal. The experiments showed that the proposed model obtains a very high accuracy (97.4%) and outperforms previous researches on the seven different task benchmarks from the Human Connectome Project (HCP) dataset. The visualization analysis further illustrated the hierarchical emergence of task-specific masks with depth. Finally, the model was retrained to regress individual traits within the HCP and to classify viewing images from the BOLD5000 dataset, respectively. Transfer learning also achieves good performance. Further visualization analysis shows that, after transfer learning, low-level attention masks remained similar to the source domain, whereas high-level attention masks changed adaptively. In conclusion, the proposed 4D model with attention module performed well and facilitated interpretation of DNNs, which is helpful for subsequent research.


Asunto(s)
Conectoma , Imagen por Resonancia Magnética , Atención , Encéfalo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación
14.
Eur J Nucl Med Mol Imaging ; 49(10): 3492-3507, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35366079

RESUMEN

PURPOSE: Multiple sclerosis (MS) is a disease characterized by inflammatory demyelinated lesions. New treatment strategies are being developed to stimulate myelin repair. Quantitative myelin imaging could facilitate these developments. This first-in-man study aimed to evaluate [11C]MeDAS as a PET tracer for myelin imaging in humans. METHODS: Six healthy controls and 11 MS patients underwent MRI and dynamic [11C]MeDAS PET scanning with arterial sampling. Lesion detection and classification were performed on MRI. [11C]MeDAS time-activity curves of brain regions and MS lesions were fitted with various compartment models for the identification of the best model to describe [11C]MeDAS kinetics. Several simplified methods were compared to the optimal compartment model. RESULTS: Visual analysis of the fits of [11C]MeDAS time-activity curves showed no preference for irreversible (2T3k) or reversible (2T4k) two-tissue compartment model. Both volume of distribution and binding potential estimates showed a high degree of variability. As this was not the case for 2T3k-derived net influx rate (Ki), the 2T3k model was selected as the model of choice. Simplified methods, such as SUV and MLAIR2 correlated well with 2T3k-derived Ki, but SUV showed subject-dependent bias when compared to 2T3k. Both the 2T3k model and the simplified methods were able to differentiate not only between gray and white matter, but also between lesions with different myelin densities. CONCLUSION: [11C]MeDAS PET can be used for quantification of myelin density in MS patients and is able to distinguish differences in myelin density within MS lesions. The 2T3k model is the optimal compartment model and MLAIR2 is the best simplified method for quantification. TRIAL REGISTRATION: NL7262. Registered 18 September 2018.


Asunto(s)
Esclerosis Múltiple , Sustancia Blanca , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Humanos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Vaina de Mielina/patología , Tomografía de Emisión de Positrones/métodos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología
15.
Chemistry ; 28(4): e202103114, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34820923

RESUMEN

We designed, synthesized, and characterized a tri-block copolymer. Its hydrophobic part, a chain of histone deacetylase inhibitor (HDACi) prodrug, was symmetrically flanked by two identical PEG blocks, whereas the built-in HDACi was a linear molecule, terminated with a thiol at one end, and a hydroxyl group at the other. Such a feature facilitated end-to-end linkage of prodrugs through alternatively aligned disulfides and carbonates. The disulfides served dual roles: redox sensors of smart nanomedicine, and warheads of masked HDACi drugs. This approach, carefully designed to benefit both control-release and efficacy, is conceptually novel for optimizing drug units in nanomedicine. Micelles from this designer polyprodrug released only PEG, CO2 and HDACi, and synergized with DOX against HCT116 cells, demonstrating its widespread potential in combination therapy. Our work highlights, for the first time, the unique advantage of thiol-based drug molecules in nanomedicine design.


Asunto(s)
Inhibidores de Histona Desacetilasas , Profármacos , Doxorrubicina , Micelas , Polietilenglicoles
16.
Proc Natl Acad Sci U S A ; 116(33): 16378-16383, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31346089

RESUMEN

Triosephosphate isomerase (TIM) barrel proteins have not only a conserved architecture that supports a myriad of enzymatic functions, but also a conserved folding mechanism that involves on- and off-pathway intermediates. Although experiments have proven to be invaluable in defining the folding free-energy surface, they provide only a limited understanding of the structures of the partially folded states that appear during folding. Coarse-grained simulations employing native centric models are capable of sampling the entire energy landscape of TIM barrels and offer the possibility of a molecular-level understanding of the readout from sequence to structure. We have combined sequence-sensitive native centric simulations with small-angle X-ray scattering and time-resolved Förster resonance energy transfer to monitor the formation of structure in an intermediate in the Sulfolobus solfataricus indole-3-glycerol phosphate synthase TIM barrel that appears within 50 µs and must at least partially unfold to achieve productive folding. Simulations reveal the presence of a major and 2 minor folding channels not detected in experiments. Frustration in folding, i.e., backtracking in native contacts, is observed in the major channel at the initial stage of folding, as well as late in folding in a minor channel before the appearance of the native conformation. Similarities in global and pairwise dimensions of the early intermediate, the formation of structure in the central region that spreads progressively toward each terminus, and a similar rate-limiting step in the closing of the ß-barrel underscore the value of combining simulation and experiment to unravel complex folding mechanisms at the molecular level.


Asunto(s)
Indol-3-Glicerolfosfato Sintasa/química , Conformación Proteica , Pliegue de Proteína , Triosa-Fosfato Isomerasa/química , Secuencia de Aminoácidos , Transferencia Resonante de Energía de Fluorescencia , Indol-3-Glicerolfosfato Sintasa/genética , Modelos Moleculares , Estructura Secundaria de Proteína , Dispersión del Ángulo Pequeño , Sulfolobus solfataricus/enzimología , Termodinámica , Triosa-Fosfato Isomerasa/genética
17.
Int J Mol Sci ; 23(21)2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36362052

RESUMEN

Neutrophils play a pivotal role in innate immunity by releasing neutrophils extracellular traps (NETs). Excessive NETs are detrimental to the local tissue and further exacerbate inflammation. Protein arginine deiminases (PAD) mediate histone citrullination and NET formation that, in turn, exacerbate endotoxin shock damages. In this study, we further investigated the molecular mechanism underlying PAD and NETs in endotoxic stress in mice. The control group mice were injected with solvent, the LPS endotoxic shock group mice were intraperitoneally injected with LPS at 35 mg/kg only, while the LPS and PAD inhibitor YW3-56 treatment group mice were injected with YW3-56 at 10 mg/kg prior to the LPS injection. YW3-56 significantly prolonged the survival time of the LPS-treated mice. NETs, cfDNA, and inflammatory factors were detected by ELISA in serum, paitoneal cavity, and lung at 24 h after LPS administration. Lung injuries were detected by immunostaining, and lung tissue transcriptomes were analyzed by RNA-seq at 24 h after LPS administration. We found that YW3-56 altered neutrophil tissue homeostasis, inhibited NET formation, and significantly decreased cytokines (IL-6, TNFα and IL-1ß) levels, cytokines gene expression, and lung tissue injury. In summary, NET formation inhibition offers a new avenue to manage inflammatory damages under endotoxic stress.


Asunto(s)
Trampas Extracelulares , Inflamación , Choque Séptico , Animales , Ratones , Citocinas/metabolismo , Trampas Extracelulares/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Lipopolisacáridos/metabolismo , Neutrófilos/metabolismo , Desiminasas de la Arginina Proteica/antagonistas & inhibidores , Desiminasas de la Arginina Proteica/metabolismo , Choque Séptico/inducido químicamente , Choque Séptico/tratamiento farmacológico , Choque Séptico/metabolismo
18.
Hum Brain Mapp ; 42(6): 1910-1919, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33417309

RESUMEN

White matter hyperintensities (WMH) are common in elderly individuals and cause brain network deficits. However, it is still unclear how the global brain network is affected by the focal WMH. We aimed to investigate the diffusion of WMH-related deficits along the connecting white matters (WM). Brain magnetic resonance imaging data and neuropsychological evaluations of 174 participants (aged 74 ± 5 years) were collected and analyzed. For each participant, WMH lesions were segmented using a deep learning method, and 18 major WM tracts were reconstructed using automated quantitative tractography. The diffusion characteristics of distal WM tracts (with the WMH penumbra excluded) were calculated. Multivariable linear regression analysis was performed. We found that a high burden of tract-specific WMH was related to worse diffusion characteristics of distal WM tracts in a wide range of WM tracts, including the forceps major (FMA), forceps minor (FMI), anterior thalamic radiation (ATR), cingulum cingulate gyrus (CCG), corticospinal tract (CST), inferior longitudinal fasciculus (ILF), superior longitudinal fasciculus-parietal (SLFP), superior longitudinal fasciculus-temporal (SLFT), and uncinate fasciculus (UNC). Furthermore, a higher mean diffusivity (MD) of distal tracts was linked to worse attention and executive function in the FMI, right CCG, left ILF, SLFP, SLFT, and UNC. The effect of WMH on the microstructural integrity of WM tracts may propagate along tracts to distal regions beyond the penumbra and might eventually affect attention and executive function.


Asunto(s)
Envejecimiento/patología , Imagen de Difusión Tensora/métodos , Fibras Nerviosas Mielínicas/patología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/patología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Atención/fisiología , Aprendizaje Profundo , Función Ejecutiva/fisiología , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Leucoaraiosis/diagnóstico por imagen , Leucoaraiosis/patología , Masculino , Tractos Piramidales/diagnóstico por imagen , Tractos Piramidales/patología
19.
Cancer Invest ; 39(6-7): 539-549, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33979257

RESUMEN

The study aimed to investigate the influence of LINC00958 on the EMT process of hepatocellular carcinoma (HCC). In our study, The LINC00958 was up-regulated in HCC tissues and cell lines. LINC00958 silencing inhibited cell proliferation, migration, and EMT process of HCC. The analysis of TCGA and StarBase showed that NUDT19 was a direct target of LINC00958 and was positively regulated by LINC00958. Besides, NUDT19 activated mTORC1/P70S6K signalling pathway. Both NUDT19 overexpression and mTORC1 activator MYH1485 reversed the inhibitory effect of LINC00958 silencing on proliferation, migration, and EMT process of HCC. In conclusion, LINC00958 silencing inhibited the proliferation, migration, and EMT process of HCC via inhibiting NUDT19 mediated mTORC1/P70S6K signalling pathway.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Pirofosfatasas/genética , ARN Largo no Codificante/genética , Regulación hacia Arriba , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética , Transducción de Señal
20.
Bioorg Chem ; 110: 104741, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33647739

RESUMEN

Platinum(II)-based chemotherapeutics are commonly used to treat various types of solid tumors, such as lung cancers. However, these compounds can cause serious side effects, including nephrotoxicity and ototoxicity, which affect the quality of life of patients. In our work, four novel dual target platinum(IV) complexes were designed and synthesized. In vitro results indicated that the title platinum(IV) complexes exhibited effective antitumor activities against the tested cancer cells and had lower toxicity and resistance factors than oxaliplatin and cisplatin. Further mechanistic experiments demonstrated that complex 11 accumulated in mitochondria and induced an elevation in ROS and an ER stress response via mitochondrial dysfunction. Notably, complex 11 significantly modulated the expression levels of proapoptosis proteins including cleaved-Caspase-3, Bax, and p53, and decreased the level of the prosurvival protein Bcl-2. Together, these results suggested that complex 11 might be a potential lead compound for future cancer therapy due to its potency and selectivity.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Daño del ADN/efectos de los fármacos , Compuestos Organoplatinos/química , Compuestos Organoplatinos/farmacología , Células A549 , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Humanos , Estructura Molecular
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