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1.
Theranostics ; 14(9): 3565-3582, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948069

RESUMEN

Cancer therapy has moved from single agents to more mechanism-based targeted approaches. In recent years, the combination of HDAC inhibitors and other anticancer chemicals has produced exciting progress in cancer treatment. Herein, we developed a novel prodrug via the ligation of dichloroacetate to selenium-containing potent HDAC inhibitors. The effect and mechanism of this compound in the treatment of prostate cancer were also studied. Methods: The concerned prodrug SeSA-DCA was designed and synthesized under mild conditions. This compound's preclinical studies, including the pharmacokinetics, cell toxicity, and anti-tumor effect on prostate cancer cell lines, were thoroughly investigated, and its possible synergistic mechanism was also explored and discussed. Results: SeSA-DCA showed good stability in physiological conditions and could be rapidly decomposed into DCA and selenium analog of SAHA (SeSAHA) in the tumor microenvironment. CCK-8 experiments identified that SeSA-DCA could effectively inhibit the proliferation of a variety of tumor cell lines, especially in prostate cancer. In further studies, we found that SeSA-DCA could also inhibit the metastasis of prostate cancer cell lines and promote cell apoptosis. At the animal level, oral administration of SeSA-DCA led to significant tumor regression without obvious toxicity. Moreover, as a bimolecular coupling compound, SeSA-DCA exhibited vastly superior efficacy than the mixture with equimolar SeSAHA and DCA both in vitro and in vivo. Our findings provide an important theoretical basis for clinical prostate cancer treatment. Conclusions: Our in vivo and in vitro results showed that SeSA-DCA is a highly effective anti-tumor compound for PCa. It can effectively induce cell cycle arrest and growth suppression and inhibit the migration and metastasis of PCa cell lines compared with monotherapy. SeSA-DCA's ability to decrease the growth of xenografts is a little better than that of docetaxel without any apparent signs of toxicity. Our findings provide an important theoretical basis for clinical prostate cancer treatment.


Asunto(s)
Apoptosis , Puntos de Control del Ciclo Celular , Inhibidores de Histona Desacetilasas , Neoplasias de la Próstata , Fosfatasas cdc25 , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Humanos , Animales , Apoptosis/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Inhibidores de Histona Desacetilasas/química , Línea Celular Tumoral , Puntos de Control del Ciclo Celular/efectos de los fármacos , Fosfatasas cdc25/metabolismo , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Ratones Desnudos , Selenio/farmacología , Selenio/química , Selenio/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Profármacos/farmacología , Profármacos/química , Ratones Endogámicos BALB C
2.
J Neural Eng ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38986464

RESUMEN

Eye-tracking research has proven valuable in understanding numerous cognitive functions. Recently, Frey et al. provided an exciting deep learning method for learning eye movements from functional magnetic resonance imaging (fMRI) data. It employed the multi-step co-registration of fMRI into the group template to obtain eyeball signal, and thus required additional templates and was time consuming. To resolve this issue, in this paper, we propose a framework named MRGazer for predicting eye gaze points from fMRI in individual space. The MRGazer consists of an eyeball extraction module and a residual network-based eye gaze prediction module. Compared to the previous method, the proposed framework skips the fMRI co-registration step, simplifies the processing protocol, and achieves end-to-end eye gaze regression. The proposed method achieved superior performance in eye fixation regression (Euclidean error, EE=2.04°) than the co-registration-based method (EE=2.89°), and delivered objective results within a shorter time (~0.02 second/volume) than prior method (~0.3 second/volume). The code is available at https://github.com/ustc-bmec/MRGazer.

3.
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.

4.
Neuroimage Clin ; 43: 103618, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38830274

RESUMEN

Extensive neuroimaging abnormalities in subcortical regions build the pathophysiological basis of Wilson's disease (WD). Yet, subcortical topographic organization fails to articulate, leaving a huge gap in understanding the neural mechanism of WD. Thus, how functional abnormalities of WD subcortical regions influence complex clinical symptoms and response to treatment remain unknown. Using resting-state functional MRI data from 232 participants (including 130 WD patients and 102 healthy controls), we applied a connectivity-based parcellation technique to develop a subcortical atlas for WD. The atlas was further used to investigate abnormalities in subcortical function (ASF) by exploring intrasubcortical functional connectivity (FC) and topographic organization of cortico-subcortical FC. We further used support vector machine (SVM) to integrate these functional abnormalities into the ASF score, which serves as a biomarker for characterizing individual subcortical dysfunction for WD. Finally, the baseline ASF score and one-year treatment data of the follow-up WD patients were used to assess treatment response. A group set of subcortical parcellations was evaluated, in which 26 bilateral regions well recapitulated the anatomical nuclei of the subcortical areas of WD. The results of cortico-subcortical FC and intrasubcortical FC reveal that dysfunction of the somatomotor networks-lenticular nucleus-thalamic pathways is involved in complex symptoms of WD. The ASF score was able to characterize disease progression and was significantly associated with treatment response of WD. Our findings provide a comprehensive elaboration of functional abnormalities of WD subcortical regions and reveal their association with clinical presentations, improving our understanding of the functional neural underpinnings in WD. Furthermore, abnormalities in subcortical function could serve as a potential biomarker for understanding the disease progression and evaluating treatment response of WD.

5.
Food Funct ; 15(11): 5955-5971, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38738998

RESUMEN

The structural characteristics of fucoidans exhibit species and regional diversity. Previous studies have demonstrated that Laminaria japonica- and Ascophyllum nodosum-derived fucoidans have type I and type II fucosyl chains, respectively. These chemical differences may contribute to distinct hypolipidemic effects and mechanisms of action. Chemical analysis demonstrated that the percentage contents of sulfate, glucuronic acid, and galactose were higher in L. japonica-derived fucoidans than those of A. nodosum-derived fucoidans. In hyperlipidemic apolipoprotein E-deficient mice, both A. nodosum- and L. japonica-derived fucoidans significantly decreased the plasma and hepatic levels of total cholesterol and triglyceride, leading to the reduction of atherosclerotic plaques. Western blotting experiments demonstrated that these fucoidans significantly enhanced the expression and levels of scavenger receptor B type 1, cholesterol 7 alpha-hydroxylase A1, and peroxisome proliferator-activated receptor (PPAR)-α, contributing to circulating lipoprotein clearance and fatty acid degradation, respectively. Differentially, L. japonica-derived fucoidan significantly increased the LXR/ATP-binding cassette G8 signaling pathway in the small intestine, as revealed by real-time quantitative PCR, which may lead to further cholesterol and other lipid excretion. Collectively, these data are useful for understanding the hypolipidemic mechanisms of action of seaweed-derived fucoidans, and their potential application for the prevention and/or treatment of atherosclerotic cardiovascular diseases.


Asunto(s)
Apolipoproteínas E , Ascophyllum , Hipolipemiantes , Laminaria , Polisacáridos , Animales , Laminaria/química , Ascophyllum/química , Ratones , Polisacáridos/farmacología , Polisacáridos/química , Hipolipemiantes/farmacología , Apolipoproteínas E/genética , Masculino , Ratones Endogámicos C57BL , Triglicéridos/sangre , Triglicéridos/metabolismo , Colesterol/sangre , Colesterol/metabolismo , Ratones Noqueados , PPAR alfa/metabolismo , PPAR alfa/genética , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/química , Hígado/metabolismo , Hígado/efectos de los fármacos , Humanos , Algas Comestibles
6.
J Hazard Mater ; 473: 134591, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38761763

RESUMEN

Selenium (Se(VI)) is environmentally toxic. One of the most popular reducing agents for Se(VI) remediation is zero-valent iron (ZVI). However, most ZVI studies were carried out in water matrices, and the recovery of reduced Se has not been investigated. A water-sediment system constructed using natural sediment was employed here to study in-situ Se remediation and recovery. A combined effect of ZVI and unacclimated microorganisms from natural sediment was found in Se(VI) removal in the water phase with a removal efficiency of 92.7 ± 1.1% within 7 d when 10 mg L-1 Se(VI) was present. Soluble Se(VI) was removed from the water and precipitated to the sediment phase (74.8 ± 0.1%), which was enhanced by the addition of ZVI (83.3 ± 0.3%). The recovery proportion of the immobilized Se was 34.2 ± 0.1% and 92.5 ± 0.2% through wet and dry magnetic separation with 1 g L-1 ZVI added, respectively. The 16 s rRNA sequencing revealed the variations in the microbial communities in response to ZVI and Se, which the magnetic separation could potentially mitigate in the long term. This study provides a novel technique to achieve in-situ Se remediation and recovery by combining ZVI reduction and magnetic separation.


Asunto(s)
Sedimentos Geológicos , Hierro , Selenio , Contaminantes Químicos del Agua , Selenio/química , Hierro/química , Contaminantes Químicos del Agua/química , Sedimentos Geológicos/microbiología , Sedimentos Geológicos/química , Bacterias/metabolismo , Bacterias/genética , Biodegradación Ambiental , ARN Ribosómico 16S/genética , Fenómenos Magnéticos
7.
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
8.
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.

9.
J Med Chem ; 67(10): 7973-7994, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38728549

RESUMEN

Triple-negative breast cancer is a highly aggressive and heterogeneous breast cancer subtype characterized by early metastasis, poor prognosis, and high recurrence. Targeting histone citrullination-mediated chromatin dysregulation to induce epigenetic alterations shows great promise in TNBC therapy. We report the synthesis, optimization, and evaluation of a novel series of ß-carboline-derived peptidyl arginine deiminase 4 inhibitors that exhibited potent inhibition of TNBC cell proliferation. The most outstanding PAD4 inhibitor, compound 28, hindered the PAD4-H3cit-NET signaling pathway and inhibited the growth of solid tumors and pulmonary metastatic nodules in the 4T1 in situ mouse model. Furthermore, 28 improved the tumor immune microenvironment by reshaping neutrophil phenotype, upregulating the proportions of dendritic cells and M1 macrophages, and reducing the amount of myeloid-derived suppressor cells. In conclusion, our work offered 28 as an efficacious PAD4 inhibitor that exerts a combination of conventional chemotherapy and immune-boosting effects, which represents a potential therapy strategy for TNBC.


Asunto(s)
Antineoplásicos , Carbolinas , Neutrófilos , Arginina Deiminasa Proteína-Tipo 4 , Neoplasias de la Mama Triple Negativas , Microambiente Tumoral , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/inmunología , Carbolinas/farmacología , Carbolinas/química , Carbolinas/uso terapéutico , Carbolinas/síntesis química , Animales , Arginina Deiminasa Proteína-Tipo 4/antagonistas & inhibidores , Femenino , Humanos , Microambiente Tumoral/efectos de los fármacos , Ratones , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Neutrófilos/inmunología , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ratones Endogámicos BALB C , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/uso terapéutico , Fenotipo , Relación Estructura-Actividad
10.
J Thorac Imaging ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38639385

RESUMEN

PURPOSE: Pulmonary inflammatory pseudotumor (PIP) is an inflammatory proliferative tumor-like lesion that frequently exhibits hypermetabolism on 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography imaging (PET/CT) and is readily misdiagnosed as a malignant tumor. The purpose of this study was to identify PIP by combining PET/computed tomography metabolic and blood test characteristics with machine learning. PATIENTS AND METHODS: We recruited 27 patients with PIP and 28 patients with lung cancer (LC). The PET metabolic and blood test parameters were collected, and the differences between the groups were evaluated. In addition, we combined the support vector machine (SVM) classifier with the indicators that differed between the groups to classify PIP and LC. RESULTS: For PET metabolic parameters, our findings showed that, as compared with the LC group, maximal standardized uptake value (P< 0.001, t = -4.780), Mean standardized uptake value SUVmean, P< 0.001, t = -4.946), and SD40% (P< 0.001, t = -4.893) were considerably reduced in the PIP group, whereas CV40% (P= 0.004, t = 3.012) was significantly greater. For blood test parameters, the total white blood cell count (P< 0.001, t= 6.457) and absolute neutrophil count (P< 0.001, t= 6.992) were substantially higher in the PIP group than in the LC group. Furthermore, the performance of SVM trained solely on PET metabolic parameters (mean area under the curve [AUC] = 0.84) was comparable to that of SVM trained solely on blood test parameters (mean AUC = 0.86). Surprisingly, utilizing the combined parameters increased SVM performance significantly (mean AUC = 0.98). CONCLUSION: PET metabolic and blood test parameters differed significantly between the PIP and LC groups, and the SVM paradigm using these significantly different features has the potential to be used to classify PIP and LC, which has important clinical implications.

11.
Med Eng Phys ; 126: 104140, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38621843

RESUMEN

Oral cancer is a common malignant tumor, and total closed resection is a common treatment. However, it has always been a challenge to determine the exact extent of excision during surgery. The application of medical image examination in surgery can provide important reference information, but the current methods still have some limitations. This study explored the application of gels based on medical image examination in the total closed resection of oral cancer patients to improve the accuracy of resection range and surgical treatment effect. The study collected medical image data of patients with oral cancer for image enhancement and determination of resection boundaries. By comparing the results of the experimental group and the control group, the application effect of gel in operation was evaluated. Through the application of medical image inspection technology, the determination of surgical resection boundary is more accurate, and the positive incisal margin of patients is effectively avoided. Gel technology improves the success rate and efficacy of surgery, and this method helps to improve the accuracy of surgery and the certainty of the scope of resection, which is of great significance for improving the surgical treatment effect and the survival rate of patients.


Asunto(s)
Márgenes de Escisión , Neoplasias de la Boca , Humanos , Neoplasias de la Boca/diagnóstico por imagen , Neoplasias de la Boca/cirugía
12.
Pharmaceutics ; 16(3)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38543229

RESUMEN

Protein arginine deiminase 4 (PAD4) plays an important role in cancer progression by participating in gene regulation, protein modification, and neutrophil extracellular trap (NET) formation. Many reversible and irreversible PAD4 inhibitors have been reported recently. In this review, we summarize the structure-activity relationships of newly investigated PAD4 inhibitors to bring researchers up to speed by guiding and describing new scaffolds as optimization and development leads for new effective, safe, and selective cancer treatments. In addition, some recent reports have shown evidence that PAD4 inhibitors are expected to trigger antitumor immune responses, regulate immune cells and related immune factors, enhance the effects of immune checkpoint inhibitors, and enhance their antitumor efficacy. Therefore, PAD4 inhibitors may potentially change tumor immunotherapy and provide an excellent direction for the development and clinical application of immunotherapy strategies for related diseases.

13.
Heliyon ; 10(5): e26197, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38495127

RESUMEN

Intermittent exotropia (IXT) is characterized by intermittently outward deviation of the eye and involved with vergence dysfunction. This study aimed to investigate the brain areas related to voluntary convergence and cortical activation changes between IXT patients and normal subjects. A total of 21 subjects, including 11 IXT patients and 10 age- and sex-matched normal subjects, were recruited for this study. A voluntary convergence task was employed, with changes in brain function measured by functional magnetic resonance imaging (fMRI). Correlations between cortical activation and clinical measurements were conducted by Pearson's correlation analysis. fMRI results showed that during voluntary convergence, the medial frontal gyrus (MFG) and bilateral occipital cortex were activated in the normal group, whereas only activation of the occipital cortex in IXT patients. Compared with the normal, IXT patients showed hypo-activation of both the MFG and cuneus during the task. The activation of MFG was negatively correlated to the duration of IXT. This study demonstrates that both MFG and occipital cortex may participate in voluntary convergence in normal subjects, while IXT patients have an aberrant cortical function of the MFG and cuneus, and the duration of IXT likely influences the severity of MFG. These findings may provide valuable insights for understanding the relationship between convergence and IXT.

14.
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.

15.
NPJ Vaccines ; 9(1): 43, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38396073

RESUMEN

The advent of SARS-CoV-2 variants with defined mutations that augment pathogenicity and/or increase immune evasiveness continues to stimulate global efforts to improve vaccine formulation and efficacy. The extraordinary advantages of lipid nanoparticles (LNPs), including versatile design, scalability, and reproducibility, make them ideal candidates for developing next-generation mRNA vaccines against circulating SARS-CoV-2 variants. Here, we assess the efficacy of LNP-encapsulated mRNA booster vaccines encoding the spike protein of SARS-CoV-2 for variants of concern (Delta, Omicron) and using a predecessor (YN2016C isolated from bats) strain spike protein to elicit durable cross-protective neutralizing antibody responses. The mRNA-LNP vaccines have desirable physicochemical characteristics, such as small size (~78 nm), low polydispersity index (<0.13), and high encapsulation efficiency (>90%). We employ in vivo bioluminescence imaging to illustrate the capacity of our LNPs to induce robust mRNA expression in secondary lymphoid organs. In a BALB/c mouse model, a three-dose subcutaneous immunization of mRNA-LNPs vaccines achieved remarkably high levels of cross-neutralization against the Omicron B1.1.529 and BA.2 variants for extended periods of time (28 weeks) with good safety profiles for all constructs when used in a booster regime, including the YN2016C bat virus sequences. These findings have important implications for the design of mRNA-LNP vaccines that aim to trigger durable cross-protective immunity against the current and newly emerging variants.

16.
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
17.
J Chromatogr A ; 1716: 464643, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38232639

RESUMEN

Peptidyl arginine deiminase 4 (PAD4) is an important biocatalytic enzymes involved in the conversion of protein arginine to citrulline, its dysregulation has a great impact on many physiological processes. Recently, PAD4 has emerged as a potential therapeutic target for the treatment of various diseases including rheumatoid arthritis (RA). Traditional Chinese Medicines (TCMs), also known as herbal plants, have gained great attention by the scientific community due to their good therapeutic performance and far fewer side effects observed in the clinical treatment. However, limited researches have been reported to screen natural PAD4 inhibitors from herbal plants. The color developing reagent (COLDER) or fluorescence based methods have been widely used in PAD4 activity assay and inhibitor screening. However, both methods measure the overall absorbance or fluorescence in the reaction solution, which are easy to be affected by the background interference due to colorful extracts from herbal plants. In this study, a simple, and robust high-performance liquid chromatography ultraviolet-visible (HPLC-UV) based method was developed to determine PAD4 activity. The proposed strategy was established based on COLDER principle, while used hydrophilic l-arginine instead of hydrophobic N-benzoyl-l-arginine ethyl ester (BAEE) as a new substrate to determine PAD4 inhibition activity of herbal extracts. The herbal extracts and PAD4 generated hydrophobic l-citrulline were successfully separated by the HPLC, and the developed method was optimized and validated with a known PAD4 inhibitor (GSK484) in comparison with COLDER assay. The IC50 value of GSK484 measured by HPLC-UV method was 153 nM, and the detection limit of the citrulline was 0.5 nmol, respectively, with a linear range of 0.5 nmol to 20 nmol. The IC50 value of the HPLC-UV method was improved by nearly three times compared with COLDER assay (527 nM), and the results indicated the reliability of PAD4 inhibition via HPLC-UV method. The inhibitory effect against PAD4 were fast and accurately screened for the twenty-four extracts from eight herbs. Among them, Ephedra Herba extracts showed significant inhibitory activity against the PAD4 with the IC50 values of three extracts (ethanol, ethyl acetate and water) ranging from 29.11 µg/mL to 41.36 µg/mL, which may help researchers to discover novel natural compounds holding high PAD4 inhibition activity.


Asunto(s)
Productos Biológicos , Medicamentos Herbarios Chinos , Inhibidores Enzimáticos , Arginina Deiminasa Proteína-Tipo 4 , Cromatografía Líquida de Alta Presión , Citrulina , Arginina Deiminasa Proteína-Tipo 4/antagonistas & inhibidores , Reproducibilidad de los Resultados , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Medicamentos Herbarios Chinos/química
18.
Polymers (Basel) ; 16(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38201819

RESUMEN

A large number of non-degradable materials have severely damaged the ecological environment. Now, people are increasingly pursuing the use of environmentally friendly materials to replace traditional chemical materials. Polyhydroxyalkonates (PHAs) are receiving increasing attention because of the unique biodegradability and biocompatibility they offer. However, the applications of PHAs are still limited due to high production costs and insufficient study. This project examines the optimal electrospinning parameters for the production of PHA-based fibrous membranes for air filtration. A common biodegradable polyester, Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), was electrospun into a nanofibrous membrane with a well-controlled surface microstructure. In order to produce smooth, bead-free fibers with micron-scale diameters, the effect of the process parameters (applied electric field, solution flow rate, inner diameter of hollow needle, and polymer concentration) on the electrospun fiber microstructure was optimized. The well-defined fibrous structure was optimized at an applied electric field of 20 kV, flow rate of 0.5 mL/h, solution concentration of 12 wt.%, and needle inner diameter of 0.21 mm. The morphology of the electrospun PHBV fibrous membrane was observed by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) and Raman spectroscopy were used to explore the chemical signatures and phases of the electrospun PHBV nanofiber. The ball burst strength (BBS) was measured to assess the mechanical strength of the membrane. The small pore size of the nanofiber membranes ensured they had good application prospects in the field of air filtration. The particle filtration efficiency (PFE) of the optimized electrospun PHBV fibrous membrane was above 98% at standard atmospheric pressure.

19.
Adv Healthc Mater ; 13(6): e2302786, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37837308

RESUMEN

Animal-derived basement-membrane matrices such as Geltrex are used to grow cells and tissues. Particularly, these are commonly applied to support tumor growth in animals for cancer research. However, a material derived from an animal source has an undefined composition, and may thus have unavoidable batch-to-batch variation in properties. To overcome these issues, a series of synthetic short peptides to form hydrogels is designed in combination with gelatin to promote cell adhesion and growth. The peptides have sequences of (X1Y1X2Y2)2 , where X1 and X2 are hydrophobic residues, while Y1 and Y2 are hydrophilic residues. The peptides spontaneously fold and self-assemble into a ß-sheet secondary structure upon contact with salts, and then aggregate to form hydrophilic networks of hydrogels. Hybrid hydrogels formed by mixing the peptide IEVEIRVK (IVK8) with gelatin are injectable and enzymatically degradable. The hybrid hydrogels at optimal compositions support SW480 and HepG2 tumor spheroid growth in vitro as effectively as Geltrex. More importantly, the peptide/gelatin hydrogels support tumor growth in a SW480 human colorectal adenocarcinoma xenograft mouse model. Altogether, the results illustrate that the synthetic peptide/gelatin hybrid hydrogel is a promising scaffold that can be used to support cell and tissue growth both in vitro and in vivo.


Asunto(s)
Neoplasias Colorrectales , Gelatina , Humanos , Animales , Ratones , Membrana Basal , Modelos Animales de Enfermedad , Hidrogeles/farmacología , Péptidos/farmacología
20.
Anim Nutr ; 15: 320-331, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38053803

RESUMEN

This study was conducted to evaluate the effects of dietary crude protein (CP) and rumen-protected lysine (RPL) supplementation on lactation performance, amino acid (AA) balance, nitrogen (N) utilization and hindgut microbiota in dairy cows. Treatments were in a 2 × 2 factorial arrangement, and the main effects were CP concentration (16% vs. 18%) and RPL supplementation (with or without RPL at 40 g/cow per day). Forty cows were randomly allocated to 4 groups: low-CP diet (LP), low-CP diet plus RPL (LPL), high-CP diet (HP), high-CP diet plus RPL (HPL). The experiment was conducted for 8 weeks. Results showed that RPL increased the dry matter intake (P < 0.01), milk protein yield (P = 0.04) and energy corrected milk (P = 0.04), and tended to increase milk fat yield (P = 0.06) and fat corrected milk (P = 0.05). Cows in the HP group tended to have higher milk urea N (P = 0.07). Plasma concentrations of Arg, Ile, Lys, Met, Pro, total essential AA and total nonessential AA were increased by RPL (P < 0.05). The total essential AA, total nonessential AA and most AA (except Ile, Phe, Gly and Pro) were increased in the HP group (P < 0.05). N excretion was increased in the HP group through an increase in urea N excretion (P < 0.01) and an upward trend in plasma urea N (P = 0.07). In addition, RPL tended to increase milk protein N secretion (P = 0.08), milk N (P = 0.07) and microbial protein synthesis (P = 0.06), and decreased plasma urea N (P < 0.001). In the hindgut, the bacterial community were different between the LP and LPL groups (P < 0.01). The probiotic abundances of Christensenellaceae_R-7_group and Acinetobacter were increased by RPL (P = 0.03 and 0.03, respectively). The pathogenic abundances of Clostridium_sensu_stricto_1 (P < 0.001) and Turicibacter (P < 0.01) were decreased by RPL. In conclusion, supplementing RPL with low dietary CP could balance AA supply and increase milk protein yield, resulting in an improvement in N utilization efficiency, and altered the composition of the hindgut microbiota to favor the lactation performance of dairy cows.

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