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1.
J Phys Chem Lett ; : 5436-5444, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743952

RESUMEN

The excellent reactivity of frustrated Lewis pairs (FLP) to activate small molecules has gained increasing attention in recent decades. Though the development of surface FLP (SFLP) is prompting the application of FLP in the chemical industry, the design of SFLP with superior activity, high density, and excellent stability for small-molecule activation is still challenging. Herein, we review the progress of designing SFLP by surface engineering, screening natural SFLP, and the dynamic formation of SFLP from theoretical perspectives. We highlight the breakthrough in fine-tuning the activity, density, and stability of the designed SFLP studied by using computational methods. We also discuss future challenges and directions in designing SFLP with outstanding capabilities for small-molecule activation.

2.
Acta Pharmacol Sin ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744938

RESUMEN

Primary Sjögren's syndrome (pSS) is a chronic inflammatory autoimmune disease with an unclear pathogenesis, and there is currently no approved drug for the treatment of this disease. Iguratimod, as a novel clinical anti-rheumatic drug in China and Japan, has shown remarkable efficacy in improving the symptoms of patients with pSS in clinical studies. In this study we investigated the mechanisms underlying the therapeutic effect of iguratimod in the treatment of pSS. Experimental Sjögren's syndrome (ESS) model was established in female mice by immunizing with salivary gland protein. After immunization, ESS mice were orally treated with iguratimod (10, 30, 100 mg·kg-1·d-1) or hydroxychloroquine (50 mg·kg-1·d-1) for 70 days. We showed that iguratimod administration dose-dependently increased saliva secretion, and ameliorated ESS development by predominantly inhibiting B cells activation and plasma cell differentiation. Iguratimod (30 and 100 mg·kg-1·d-1) was more effective than hydroxychloroquine (50 mg·kg-1·d-1). When the potential target of iguratimod was searched, we found that iguratimod bound to TEC kinase and promoted its degradation through the autophagy-lysosome pathway in BAFF-activated B cells, thereby directly inhibiting TEC-regulated B cells function, suggesting that the action mode of iguratimod on TEC was different from that of conventional kinase inhibitors. In addition, we found a crucial role of TEC overexpression in plasma cells of patients with pSS. Together, we demonstrate that iguratimod effectively ameliorates ESS via its unique suppression of TEC function, which will be helpful for its clinical application. Targeting TEC kinase, a new regulatory factor for B cells, may be a promising therapeutic option.

3.
Int J Biol Macromol ; 269(Pt 2): 132271, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38734330

RESUMEN

As an anti-infection antibiotic delivery route, a drug-controlled release system based on a specific condition stimulus response can enhance drug stability and bioavailability, reduce antibiotic resistance, achieve on-demand release and improve targeting and utilization efficiency. In this study, chitosan-coated liposomes containing levofloxacin (Lef@Lip@CS) were prepared with lysozyme in body fluids serving as an intelligent "switch" to enable accurate delivery of antibiotics through the catalytic degradation ability of chitosan. Good liposome encapsulation efficacy (64.89 ± 1.86 %) and loading capacity (5.28 ± 0.18 %) were achieved. The controlled-release behavior and morphological characterization before and after enzymatic hydrolysis confirmed that the levofloxacin release rate depended on the lysozyme concentration and the degrees of deacetylation of chitosan. In vitro bacteriostatic experiments showed significant differences in the effects of Lef@Lip@CS before and after enzyme addition, with 6-h inhibition rate of 72.46 % and 100 %, and biofilm removal rates of 51 % and 71 %, respectively. These findings show that chitosan-coated liposomes are a feasible drug delivery system responsive to lysozyme stimulation.

4.
Mol Neurobiol ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769227

RESUMEN

Accumulating evidence suggests that prenatal stress (PNS) increases offspring susceptibility to depression, but the underlying mechanisms remain unclear. We constructed a mouse model of prenatal stress by spatially restraining pregnant mice from 09:00-11:00 daily on Days 5-20 of gestation. In this study, western blot analysis, quantitative real-time PCR (qRT‒PCR), immunofluorescence, immunoprecipitation, chromatin immunoprecipitation (ChIP), and mifepristone rescue assays were used to investigate alterations in the GR/P300-MKP1 and downstream ERK/CREB/TRKB pathways in the brains of prenatally stressed offspring to determine the pathogenesis of the reduced neurogenesis and depression-like behaviors in offspring induced by PNS. We found that prenatal stress leads to reduced hippocampal neurogenesis and depression-like behavior in offspring. Prenatal stress causes high levels of glucocorticoids to enter the fetus and activate the hypothalamic‒pituitary‒adrenal (HPA) axis, resulting in decreased hippocampal glucocorticoid receptor (GR) levels in offspring. Furthermore, the nuclear translocation of GR and P300 (an acetylation modifying enzyme) complex in the hippocampus of PNS offspring increased significantly. This GR/P300 complex upregulates MKP1, which is a negative regulator of the ERK/CREB/TRKB signaling pathway associated with depression. Interestingly, treatment with a GR antagonist (mifepristone, RU486) increased hippocampal GR levels and decreased MKP1 expression, thereby ameliorating abnormal neurogenesis and depression-like behavior in PNS offspring. In conclusion, our study suggested that the regulation of the MKP1 signaling pathway by GR/P300 is involved in depression-like behavior in prenatal stress-exposed offspring and provides new insights and ideas for the fetal hypothesis of mental health.

5.
Mol Biotechnol ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775936

RESUMEN

Microplastics (MPs) are persistent environmental pollutants that enter the circulatory system and subsequently reduce sperm quantity and quality. However, the influence of polystyrene MPs (PS-MPs) on the ovary and relevant mechanisms remain elusive. Herein, we aimed to examine the impact of PS-MPs on oxidative disorders in ovarian tissues and elucidate the underlying mechanisms. Healthy female rats were treated with different concentrations of 0.5 µm PS-MPs (diluted in deionized H2O) for 90 days. Upon examination of hematoxylin-eosin-stained ovarian tissue sections, the number of growing follicles was reduced in PS-MP-treated rats when compared with that in control rats. Enzyme-linked immunosorbent assays revealed that PS-MP exposure markedly reduced anti-Müllerian hormone (AMH) levels. Treatment with PS-MPs downregulated superoxide dismutase, glutathione, and catalase activities in ovarian tissues while upregulating malondialdehyde levels. Furthermore, exposure to PS-MP blocked the Keap1/Nrf2/HO-1 signal transduction pathway. PS-MPs also triggered apoptosis in the ovarian tissue, as evidenced by increased TUNEL staining and expression levels of cleaved caspase-9, Bax, and Bcl-2. To reactivate the Keap1/Nrf2/HO-1 pathway, rats were co-administered PS-MPs and omaveloxolone (Oma), an Nrf2 activator, for 1 week. We found that Oma could counteract the PS-MP-mediated effects on oxidative disorder, apoptosis, AMH production, and follicle number in rat ovarian tissues. To develop an in vitro model, granulosa cells (GCs) were treated with 10 µM H2O2 for 12 h to induce oxidative stress. H2O2-stimulated GCs exhibited attenuated cell growth and upregulated apoptosis and oxidative stress. Oma administration could ameliorate the H2O2-induced effects in terms of regulating cell viability, apoptosis, and oxidative stress in GCs. In summary, PS-MPs could induce apoptosis and oxidative stress via the Keap1/Nrf2/HO-1 signaling pathway in both rats and GCs.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38717983

RESUMEN

Current electrically heated fabrics provide heat in cold climates, suffer from abundant wasted radiant heat energy to the external environment, and are prone to damage by water. Thus, constructing energy-efficient and superhydrophobic conductive fabrics is in high demand. Therefore, we propose an effective and facile methodology to prepare a superhydrophobic, highly conductive, and trilayered fabric with a connected carbon nanotube (CNT) layer and a titanium dioxide (TiO2) nanoparticle heat-reflecting layer. We construct polyamide/fluorinated polyurethane (PA/FPU) nanofibrous membranes via first electrospinning, then performing blade-coating with the polyurethane (PU) solution with CNTs, and finally fabricating FPU/TiO2 nanoparticles via electrospraying. This strategy causes CNTs to be connected to form a conductive layer and enables TiO2 nanoparticles to be bound together to form a porous, heat-reflecting layer. As a consequence, the as-prepared membranes demonstrate high conductivity with an electrical conductivity of 63 S/m, exhibit rapid electric-heating capacity, and exhibit energy-efficient asymmetrical heating behavior, i.e., the heating temperature of the PA/FPU nanofibrous layer reaches more than 83 °C within 90 s at 24 V, while the heating temperature of the FPU/TiO2 layer only reaches 53 °C, as well as prominent superhydrophobicity with a water contact angle of 156°, indicating promising utility for the next generation of electrical heating textiles.

7.
World J Gastrointest Surg ; 16(4): 1203-1207, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38690061

RESUMEN

BACKGROUND: Gastric wall necrosis is a rare complication of endoscopic treatment for bleeding gastric ulcer, which may exacerbate the patient's condition once it occurs and may even require surgical intervention for treatment. CASE SUMMARY: A 59-year-old man was admitted to our department with melena. Endoscopy revealed a giant ulcer in the gastric antrum with a visible vessel in its center, which was treated with sclerosants and tissue glue injection and resulted in necrosis of the gastric wall. CONCLUSION: Injection of sclerosants and tissue glue may lead to gastric wall necrosis, which is a serious complication. Therefore, before administering this treatment to patients, we should consider other more effective methods of hemostasis to avoid gastric wall necrosis.

8.
Clin Exp Gastroenterol ; 17: 157-164, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38745764

RESUMEN

Purpose: Hemorrhoids (HEM) are the most common perianal disease, but current observational studies have yielded inconsistent results in investigating the risk factors. Our further exploration of the risk factors will help prevent the disease. Patients and Methods: We conducted a two-sample bidirectional Mendelian randomization (MR) analysis using publicly available genome-wide association studies (GWAS) statistics from multiple consortia. The inverse-variance weighted (IVW) method was used for the primary analysis. We applied four complementary methods, including weighted median, weighted mode, MR-Egger regression, and Cochrane's Q value, to detect and correct the effects of horizontal pleiotropy. Results: Genetically determined constipation (OR = 0.97, 95% CI: 0.91-1.03, P = 0.28) and diarrhea (OR = 1.00, 95% CI: 0.99-1.01, P = 0.90) did not have a causal effect on HEM but stool frequency (OR = 1.28, 95% CI: 1.05-1.55, P = 0.01), waist-to-hip ratio adjusted for BMI (OR = 1.11, 95% CI: 1.06-1.64, P = 1.59×10-5), and order Burkholderiales (OR = 1.09, 95% CI = 1.04-1.14, p = 1.63×10-4) had a causal effect on. Furthermore, we found a significant causal effect of constipation on HEM in the reverse MR analysis (OR = 1.21, 95% CI: 1.13-1.28, P = 3.72×10-9). The results of MR-Egger regression, Weighted Median, and Weighted Mode methods were consistent with those of the IVW method. Horizontal pleiotropy was unlikely to distort the causal estimates, as indicated by the sensitivity analysis. Conclusion: Our MR analysis reveals a causal association between stool frequency and waist-to-hip ratio with HEM, despite variations in results reported by observational studies. Unexpectedly, we found a relationship between the order Burkholderiales in the gut flora and HEM, although the mechanism is unclear.

9.
Front Bioeng Biotechnol ; 12: 1382085, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38572358

RESUMEN

In this study, a high-efficiency superparamagnetic drug delivery system was developed for preclinical treatment of bladder cancer in small animals. Two types of nanoparticles with magnetic particle imaging (MPI) capability, i.e., single- and multi-core superparamagnetic iron oxide nanoparticles (SPIONs), were selected and coupled with bladder anti-tumor drugs by a covalent coupling scheme. Owing to the minimal particle size, magnetic field strengths of 270 mT with a gradient of 3.2 T/m and 260 mT with a gradient of 3.7 T/m were found to be necessary to reach an average velocity of 2 mm/s for single- and multi-core SPIONs, respectively. To achieve this, a method of constructing an in vitro magnetic field for drug delivery was developed based on hollow multi-coils arranged coaxially in close rows, and magnetic field simulation was used to study the laws of the influence of the coil structure and parameters on the magnetic field. Using this method, a magnetic drug delivery system of single-core SPIONs was developed for rabbit bladder therapy. The delivery system consisted of three coaxially and equidistantly arranged coils with an inner diameter of Φ50 mm, radial height of 85 mm, and width of 15 mm that were positioned in close proximity to each other. CCK8 experimental results showed that the three types of drug-coupled SPION killed tumor cells effectively. By adjusting the axial and radial positions of the rabbit bladder within the inner hole of the delivery coil structure, the magnetic drugs injected could undergo two-dimensional delivery motions and were delivered and aggregated to the specified target location within 12 s, with an aggregation range of about 5 mm × 5 mm. In addition, the SPION distribution before and after delivery was imaged using a home-made open-bore MPI system that could realistically reflect the physical state. This study contributes to the development of local, rapid, and precise drug delivery and the visualization of this process during cancer therapy, and further research on MPI/delivery synchronization technology is planned for the future.

10.
Acta Pharmacol Sin ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589686

RESUMEN

Cardiopulmonary progenitor cells (CPPs) constitute a minor subpopulation of cells that are commonly associated with heart and lung morphogenesis during embryonic development but completely subside after birth. This fact offers the possibility for the treatment of pulmonary heart disease (PHD), in which the lung and heart are both damaged. A reliable source of CPPs is urgently needed. In this study, we reprogrammed human cardiac fibroblasts (HCFs) into CPP-like cells (or induced CPPs, iCPPs) and evaluated the therapeutic potential of iCPP-derived exosomes for acute lung injury (ALI). iCPPs were created in passage 3 primary HCFs by overexpressing GLI1, WNT2, ISL1 and TBX5 (GWIT). Exosomes were isolated from the culture medium of passage 6-8 GWIT-iCPPs. A mouse ALI model was established by intratracheal instillation of LPS. Four hours after LPS instillation, ALI mice were treated with GWIT-iCPP-derived exosomes (5 × 109, 5 × 1010 particles/mL) via intratracheal instillation. We showed that GWIT-iCPPs could differentiate into cell lineages, such as cardiomyocyte-like cells, endothelial cells, smooth muscle cells and alveolar epithelial cells, in vitro. Transcription analysis revealed that GWIT-iCPPs have potential for heart and lung development. Intratracheal instillation of iCPP-derived exosomes dose-dependently alleviated LPS-induced ALI in mice by attenuating lung inflammation, promoting endothelial function and restoring capillary endothelial cells and the epithelial cells barrier. This study provides a potential new method for the prevention and treatment of cardiopulmonary injury, especially lung injury, and provides a new cell model for drug screening.

11.
Exp Cell Res ; 438(2): 114053, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38663476

RESUMEN

Bladder cancer is a common tumor that impacts the urinary system and marked by a significant fatality rate and an unfavorable prognosis. Promising antineoplastic properties are exhibited by brusatol, which is obtained from the dried ripe fruit of Brucea javanica. The present study aimed to evaluate the influence of brusatol on the progression of bladder cancer and uncover the molecular mechanism involved. We used Cell Counting Kit-8, colony formation and EdU assays to detect cell numbers, viability and proliferation. We used transwell migration assay to detect cell migration ability. The mechanism of brusatol inhibition of bladder cancer proliferation was studied by flow cytometry and western blotting. It was revealed that brusatol could reduce the viability and proliferation of T24 and 5637 cells. The transwell migration assay revealed that brusatol was able to attenuate the migration of T24 and 5637 cells. We found that treatment with brusatol increased the levels of reactive oxygen species, malondialdehyde and Fe2+, thereby further promoting ferroptosis in T24 and 5637 cells. In addition, treatment with RSL3 (an agonistor of ferroptosis) ferrostatin-1 (a selective inhibitor of ferroptosis) enhanced or reversed the brusatol-induced inhibition. In vivo, treatment with brusatol significantly suppressed the tumor growth in nude mice. Mechanistically, brusatol induced ferroptosis by upregulating the expression of ChaC glutathione-specific gamma-glutamylcyclotransferase (Chac1) and decreasing the expression of SLC7A11 and Nrf2 in T24 and 5637 cells. To summarize, the findings of this research demonstrated that brusatol hindered the growth of bladder cancer and triggered ferroptosis via the Chac1/Nrf2/SLC7A11 pathway.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Movimiento Celular , Proliferación Celular , Factor 2 Relacionado con NF-E2 , Cuassinas , Neoplasias de la Vejiga Urinaria , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/genética , Cuassinas/farmacología , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Animales , Ratones , Proliferación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Ratones Desnudos , Transducción de Señal/efectos de los fármacos , Ferroptosis/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Especies Reactivas de Oxígeno/metabolismo , Progresión de la Enfermedad , Ratones Endogámicos BALB C , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos
12.
Shock ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38668801

RESUMEN

OBJECTIVE: This study aimed to explore the impact of heat stress (HS) on glutamate transmission-dependent expression levels of interleukin-1ß (IL-1ß) and IL-18 in BV-2 microglial cells. METHODS: BV-2 microglial cells were cultured in vitro, with cells maintained at 37 °C serving as the control. The HS group experienced incubation at 40 °C for 1 h, followed by further culturing at 37 °C for 6 or 12 h. The experimental group was pre-incubated with glutamate, the glutamate antagonist riluzole, or the mGluR5 agonist, 2-Chloro-5-hydroxyphenylglycine (CHPG), before HS. Glutamate content in BV-2 culture supernatant was assessed using colorimetric assay. Moreover, mRNA expression levels of EAAT3 and/or mGluR5 in BV-2 cells were determined via quantitative polymerase chain reaction. Interleukins (IL-1ß and IL-18) in cell culture supernatant were measured using enzyme-linked immunosorbent assay. Western blot analysis was employed to assess protein levels of IL-1ß and IL-18 in BV-2 cells. RESULTS: HS induced a significant release of glutamate and increased the expression levels of mGluR5 and EAAT3 in BV-2 cells. It also triggered the expression levels and release of pro-inflammatory factors, such as IL-1ß and IL-18, synergizing with the effects of glutamate treatment. Preincubation with both riluzole and CHPG significantly reduced HS-induced glutamate release and mitigated the increased expression levels and release of IL-1ß and IL-18 induced by HS. CONCLUSION: The findings confirmed that microglia could be involved in HS primarily through glutamate metabolisms, influencing the expression levels and release of IL-1ß and IL-18.

13.
Ecotoxicol Environ Saf ; 276: 116307, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38593497

RESUMEN

In recent decades, there has been increasing interest in elucidating the role of sulfur-containing compounds in plant metabolism, particularly emphasizing their function as signaling molecules. Among these, thiocyanate (SCN-), a compound imbued with sulfur and nitrogen, has emerged as a significant environmental contaminant frequently detected in irrigation water. This compound is known for its potential to adversely impact plant growth and agricultural yield. Although adopting exogenous SCN- as a nitrogen source in plant cells has been the subject of thorough investigation, the fate of sulfur resulting from the assimilation of exogenous SCN- has not been fully explored. There is burgeoning curiosity in probing the fate of SCN- within plant systems, especially considering the possible generation of the gaseous signaling molecule, hydrogen sulfide (H2S) during the metabolism of SCN-. Notably, the endogenous synthesis of H2S occurs predominantly within chloroplasts, the cytosol, and mitochondria. In contrast, the production of H2S following the assimilation of exogenous SCN- is explicitly confined to chloroplasts and mitochondria. This phenomenon indicates complex interplay and communication among various subcellular organelles, influencing signal transduction and other vital physiological processes. This review, augmented by a small-scale experimental study, endeavors to provide insights into the functional characteristics of H2S signaling in plants subjected to SCN--stress. Furthermore, a comparative analysis of the occurrence and trajectory of endogenous H2S and H2S derived from SCN--assimilation within plant organisms was performed, providing a focused lens for a comprehensive examination of the multifaceted roles of H2S in rice plants. By delving into these dimensions, our objective is to enhance the understanding of the regulatory mechanisms employed by the gasotransmitter H2S in plant adaptations and responses to SCN--stress, yielding invaluable insights into strategies for plant resilience and adaptive capabilities.


Asunto(s)
Sulfuro de Hidrógeno , Plantas , Transducción de Señal , Tiocianatos , Sulfuro de Hidrógeno/metabolismo , Tiocianatos/metabolismo , Plantas/metabolismo , Gasotransmisores/metabolismo , Cloroplastos/metabolismo , Inactivación Metabólica
14.
J Proteome Res ; 23(5): 1859-1870, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38655723

RESUMEN

To understand how upregulated isoglutaminyl cyclase (isoQC) is involved in the initiation of diseases such as cancer, we developed a human KYSE30 carcinoma cell model in which isoQC was stably overexpressed. GO and KEGG analysis of the DEGs (228) and DEPs (254) respectively implicated isoQC on the proliferation invasion and metastasis of cells and suggested that isoQC might participate in the regulation of MAPK, RAS, circadian rhythm, and related pathways. At the functional level, isoQC-overexpressing KYSE30 cells showed enhanced proliferation, migration, and invasion capacity. Next, we decided to study the precise effect of isoQC overexpression on JNK, p-JNK, AKT, p-AKT, ERK, p-ERK, and PER2, as RNA levels of these proteins are significantly correlated with signal levels indicated in RNA-Seq analysis, and these candidates are the top correlated DEPs enriched in RT-qPCR analysis. We saw that only p-ERK expression was inhibited, while PER2 was increased. These phenotypes were inhibited upon exposure to PER2 inhibitor KL044, which allowed for the restoration of p-ERK levels. These data support upregulated isoQC being able to promote cancer cell proliferation and migration in vitro, likely by helping to regulate the MAPK and RAS signaling pathways, and the circadian protein PER2 might be a potential mediator.


Asunto(s)
Aminoaciltransferasas , Movimiento Celular , Proliferación Celular , Sistema de Señalización de MAP Quinasas , Humanos , Proliferación Celular/genética , Movimiento Celular/genética , Sistema de Señalización de MAP Quinasas/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Invasividad Neoplásica , Regulación hacia Arriba , Neoplasias/genética , Neoplasias/patología , Neoplasias/metabolismo
15.
Angew Chem Int Ed Engl ; : e202405405, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578834

RESUMEN

The surface frustrated Lewis pairs (SFLPs) open up new opportunities for substituting noble metals in the activation and conversion of stable molecules. However, the applications of SFLPs on a larger scale are impeded by the complex construction process, low surface density, and sensitivity to the reaction environment. Herein, wurtzite-structured crystals such as GaN, ZnO, and AlP are found for developing natural, dense, and stable SFLPs. It is revealed that the SFLPs can naturally exist on the (100) and (110) surfaces of wurtzite-structured crystals. All the surface cations and anions serve as the Lewis acid and Lewis base in SFLPs, respectively, contributing to the surface density of SFLPs as high as 7.26×1014 cm-2. Ab initio molecular dynamics simulations indicate that the SFLPs can keep stable under high temperatures and the reaction atmospheres of CO and H2O. Moreover, outstanding performance for activating the given small molecules is achieved on these natural SFLPs, which originates from the optimal orbital overlap between SFLPs and small molecules. Overall, these findings not only provide a simple method to obtain dense and stable SFLPs but also unfold the nature of SFLPs toward the facile activation of small molecules.

16.
Clin Epigenetics ; 16(1): 42, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491513

RESUMEN

BACKGROUND: Congenital heart disease (CHD) is a prevalent congenital cardiac malformation, which lacks effective early biological diagnosis and intervention. MicroRNAs, as epigenetic regulators of cardiac development, provide potential biomarkers for the diagnosis and treatment of CHD. However, the mechanisms underlying miRNAs-mediated regulation of cardiac development and CHD malformation remain to be further elucidated. This study aimed to explore the function of microRNA-20b-5p (miR-20b-5p) in cardiac development and CHD pathogenesis. METHODS AND RESULTS: miRNA expression profiling identified that miR-20b-5p was significantly downregulated during a 12-day cardiac differentiation of human embryonic stem cells (hESCs), whereas it was markedly upregulated in plasma samples of atrial septal defect (ASD) patients. Our results further revealed that miR-20b-5p suppressed hESCs-derived cardiac differentiation by targeting tet methylcytosine dioxygenase 2 (TET2) and 5-hydroxymethylcytosine, leading to a reduction in key cardiac transcription factors including GATA4, NKX2.5, TBX5, MYH6 and cTnT. Additionally, knockdown of TET2 significantly inhibited cardiac differentiation, which could be partially restored by miR-20b-5p inhibition. CONCLUSIONS: Collectively, this study provides compelling evidence that miR-20b-5p functions as an inhibitory regulator in hESCs-derived cardiac differentiation by targeting TET2, highlighting its potential as a biomarker for ASD.


Asunto(s)
Dioxigenasas , MicroARNs , Humanos , Diferenciación Celular , Dioxigenasas/genética , ADN/metabolismo , Metilación de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , MicroARNs/genética , MicroARNs/metabolismo
17.
Adv Healthc Mater ; : e2400125, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38513154

RESUMEN

Microglia-mediated inflammation is involved in the pathogenesis of Alzheimer's disease (AD), whereas human fibroblast growth factor 21 (hFGF21) has demonstrated the ability to regulate microglia activation in Parkinson's disease, indicating a potential therapeutic role in AD. However, challenges such as aggregation, rapid inactivation, and the blood-brain barrier hinder its effectiveness in treating AD. This study develops targeted delivery of hFGF21 to activated microglia using BV2 cell membrane-coated PEGylated liposomes (hFGF21@BCM-LIP), preserving the bioactivity of hFGF21. In vitro, hFGF21@BCM-LIP specifically targets Aß1-42-induced BV2 cells, with uptake hindered by anti-VCAM-1 antibody, indicating the importance of VCAM-1 and integrin α4/ß1 interaction in targeted delivery to BV2 cells. In vivo, following subcutaneous injection near the lymph nodes of the neck, hFGF21@BCM-LIP diffuses into lymph nodes and distributes along the meningeal lymphatic vasculature and brain parenchyma in amyloid-beta (Aß1-42)-induced mice. Furthermore, the administration of hFGF21@BCM-LIP to activated microglia improves cognitive deficits caused by Aß1-42 and reduces levels of tau, p-Tau, and BACE1. It also decreases interleukin-6  (IL-6) and tumor necrosis factor-α (TNF-α) release while increasing interleukin-10 (IL-10) release both in vivo and in vitro. These results indicate that hFGF21@BCM-LIP can be a promising treatment for AD, by effectively crossing the blood-brain barrier and targeting delivery to brain microglia via the neck-meningeal lymphatic vasculature-brain parenchyma pathways.

18.
Int J Biol Macromol ; 265(Pt 1): 130894, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38490388

RESUMEN

Bamboo fibers (BF), as an important sustainable natural material, are becoming a hot alternative to synthetic fibers for the reinforcement of polypropylene (PP)-based composites. However, the weak interfacial compatibility between BF and PP as matrix and their inherent flammability limit the practical application of BF/PP composites (BPC). Here, a fire-safe BPC was fabricated by constructing flame-retardant interfacial layers containing tannic acid (TA)-Fe3+ complex and halloysite nanotubes (HNTs) on the fiber matrix followed by a hot-pressing process. The results showed that the interfacial chelating of TA with Fe3+ improved the dispersion of HNTs on the fibers and the interfacial interactions within the fiber matrix, resulting in the as-fabricated composite with significantly improved mechanical properties and water resistance. In addition, the flame-retardant composite exhibited higher thermal stability and enhanced residual char content. Moreover, the composite possessed significant flame-retardant performances with a reduction of 23.75 % in the total heat release and 32.44 % in the total smoke production, respectively, owing to the flame retarding in gaseous phase and condensed phase of TA-Fe3+@HNTs layers. This work offers a green and eco-friendly strategy to address the inherent problems of BPC material in terms of fire safety and interfacial compatibility, thus broadening their applications in the automotive interior and construction industries.


Asunto(s)
Industria de la Construcción , Retardadores de Llama , Nanotubos , Polifenoles , Arcilla , Polipropilenos
19.
BMC Cancer ; 24(1): 297, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438912

RESUMEN

BACKGROUD: We aimed to develop a novel preoperative nomogram to predict lymph node metastasis (LNM) in perihilar cholangiocarcinoma (pCCA) patients. METHODS: 160 pCCA patients were enrolled at Lihuili Hospital from July 2006 to May 2022. A novel nomogram model was established to predict LNM in pCCA patients based on the independent predictive factors selected by the multivariate logistic regression model. The precision of the nomogram model was evaluated through internal and external validation with calibration curve statistics and the concordance index (C-index). Receiver operating characteristic (ROC) curve and decision curve analysis (DCA) were used to evaluate and determine the clinical utility of the nomogram. RESULTS: Multivariate logistic regression demonstrated that age (OR = 0.963, 95% CI: 0.930-0.996, P = 0.030), CA19-9 level (> 559.8 U/mL vs. ≤559.8 U/mL: OR = 3.162, 95% CI: 1.519-6.582, P = 0.002) and tumour diameter (OR = 1.388, 95% CI: 1.083-1.778, P = 0.010) were independent predictive factors of LNM in pCCA patients. The C-index was 0.763 (95% CI: 0.667-0.860) and 0.677 (95% CI: 0.580-0.773) in training cohort and validation cohort, respectively. ROC curve analysis indicated the comparative stability and adequate discriminative ability of nomogram. The sensitivity and specificity were 0.820 and 0.652 in training cohort and 0.704 and 0.649 in validation cohort, respectively. DCA revealed that the nomogram model could augment net benefits in the prediction of LNM in pCCA patients. CONCLUSIONS: The novel prediction model is useful for predicting LNM in pCCA patients and showed adequate discriminative ability and high predictive accuracy.


Asunto(s)
Neoplasias de los Conductos Biliares , Tumor de Klatskin , Humanos , Tumor de Klatskin/cirugía , Metástasis Linfática , Antígeno CA-19-9 , Calibración , Neoplasias de los Conductos Biliares/cirugía
20.
Phytomedicine ; 128: 155423, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38518646

RESUMEN

BACKGROUND: Polycystic ovary syndrome is a metabolic and hormonal disorder that is closely linked to oxidative stress. Within individuals diagnosed with PCOS, changes occur in the ovaries, resulting in an excessive buildup of iron and peroxidation of lipids, both of which may be associated with the occurrence of ferroptosis. Baicalein, a flavonoid found in the roots of Scutellaria baicalensis and widely known as Chinese skullcap, is known for its anti-inflammatory and anti-ferroptotic properties, which protect against various diseases. Nevertheless, there has been no investigation into the impact of baicalein on polycystic ovary syndrome. PURPOSE: This study aimed to correlate ferroptosis with polycystic ovary syndrome and to assess the effects of baicalein on ovarian dysfunction and placental development in pregnant patients. STUDY DESIGN AND METHODS: Polycystic ovary syndrome was induced in a rat model through the administration of dehydroepiandrosterone, and these rats were treated with baicalein. Oxidative stress and inflammation levels were assessed in serum and ovaries, and tissue samples were collected for histological and protein analyses. Furthermore, different groups of female rats were mated with male rats to observe pregnancy outcomes and tissue samples were obtained for histological, protein, and RNA sequencing. Then, RNA sequencing of the placenta was performed to determine the key genes involved in ferroptosis negative regulation (FNR) signatures. RESULTS: Baicalein was shown to reduce ovarian oxidative stress and pathology. Baicalein also ameliorated polycystic ovary syndrome by decreasing lipid peroxidation and chronic inflammation and modulating mitochondrial functions and ferroptosis in the ovaries. Specifically, glutathione peroxidase and ferritin heavy chain 1 were considerably downregulated in polycystic ovary syndrome gravid rats compared to their expression in the control group, and most of these differences were reversed after baicalein intervention. CONCLUSIONS: Our findings, initially, indicated that baicalein could potentially enhance the prognosis of individuals suffering from polycystic ovary syndrome by reducing oxidative stress and ferroptosis, thus potentially influencing the formulation of a therapeutic approach to address this condition.


Asunto(s)
Ferroptosis , Flavanonas , Ovario , Estrés Oxidativo , Placenta , Síndrome del Ovario Poliquístico , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Femenino , Flavanonas/farmacología , Ferroptosis/efectos de los fármacos , Animales , Estrés Oxidativo/efectos de los fármacos , Embarazo , Placenta/efectos de los fármacos , Placenta/metabolismo , Ovario/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Scutellaria baicalensis/química , Modelos Animales de Enfermedad , Peroxidación de Lípido/efectos de los fármacos , Masculino
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