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1.
Artigo em Inglês | MEDLINE | ID: mdl-38627235

RESUMO

A novel double-network conductive hydrogel based on lithium acetate/gelatin/polyacrylamide (PAAM) was synthesized by heating-cooling and subsequent γ-ray radiation-induced polymerization and cross-linking. Owing to the hydrogen bonding interaction between lithium acetate, physical cross-linked gelatin, and chemical cross-linked PAAM, the resultant hydrogel exhibited high tensile strength (1260 kPa), high ionic conductivity (35.2 mS cm-1), notch-insensitivity (tensile strength 415 kPa, elongation at break 872% with transverse notch), and extensive strain monitoring range (0.15-800%) under optimum conditions. The lithium acetate/gelatin/polyacrylamide hydrogel strain sensor attached to the skin can sensitively monitor the subtle movements of the human body. The strain sensor based on the resultant hydrogel with transverse notch can still work for 1200 cycles, due to that the covalent-cross-linked PAAm chain bridges the cracks and stabilizes the deformation, while the physical-cross-linked gelatin was unzipped to make the blunting of notch. The conductive hydrogel with high-sensitivity and high stability is expected to be used as materials for the preparation of flexible strain sensors in the future.

2.
J Am Chem Soc ; 146(15): 10753-10766, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578841

RESUMO

Proteolysis targeting chimera (PROTAC) technology is an innovative strategy for cancer therapy, which, however, suffers from poor targeting delivery and limited capability for protein of interest (POI) degradation. Here, we report a strategy for the in situ formulation of antineoplastic Supra-PROTACs via intracellular sulfatase-responsive assembly of peptides. Coassembling a sulfated peptide with two ligands binding to ubiquitin VHL and Bcl-xL leads to the formation of a pro-Supra-PROTAC, in which the ratio of the two ligands is rationally optimized based on their protein binding affinity. The resulting pro-Supra-PROTAC precisely undergoes enzyme-responsive assembly into nanofibrous Supra-PROTACs in cancer cells overexpressing sulfatase. Mechanistic studies reveal that the pro-Supra-PROTACs selectively cause apparent cytotoxicity to cancer cells through the degradation of Bcl-xL and the activation of caspase-dependent apoptosis, during which the rationally optimized ligand ratio improves the bioactivity for POI degradation and cell death. In vivo studies show that in situ formulation enhanced the tumor accumulation and retention of the pro-Supra-PROTACs, as well as the capability for inhibiting tumor growth with excellent biosafety when coadministrating with chemodrugs. Our findings provide a new approach for enzyme-regulated assembly of peptides in living cells and the development of PROTACs with high targeting delivering and POI degradation efficiency.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Quimera de Direcionamento de Proteólise , Antineoplásicos/farmacologia , Sulfatases , Proteólise , Peptídeos , Ubiquitina-Proteína Ligases
3.
ACS Appl Mater Interfaces ; 16(15): 19112-19120, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38579811

RESUMO

Two-dimensional transition metal dichalcogenide (TMDC) heterostructure is receiving considerable attention due to its novel electronic, optoelectronic, and spintronic devices with design-oriented and functional features. However, direct design and synthesis of high-quality TMDC/MnTe heterostructures remain difficult, which severely impede further investigations of semiconductor/magnetic semiconductor devices. Herein, the synthesis of high-quality vertically stacked WS2/MnTe heterostructures is realized via a two-step chemical vapor deposition method. Raman, photoluminescence, and scanning transmission electron microscopy characterizations reveal the high-quality and atomically sharp interfaces of the WS2/MnTe heterostructure. WS2/MnTe-based van der Waals field effect transistors demonstrate high rectification behavior with rectification ratio up to 106, as well as a typical p-n electrical transport characteristic. Notably, the fabricated WS2/MnTe photodetector exhibits sensitive and broadband photoresponse ranging from UV to NIR with a maximum responsivity of 1.2 × 103 A/W, a high external quantum efficiency of 2.7 × 105%, and fast photoresponse time of ∼50 ms. Moreover, WS2/MnTe heterostructure photodetectors possess a broadband image sensing capability at room temperature, suggesting potential applications in next-generation high-performance and broadband image sensing photodetectors.

4.
Biomed Pharmacother ; 174: 116542, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38574620

RESUMO

Previous studies have demonstrated that the underlying mechanisms of myocardial ischemia/reperfusion injury (MIRI) are complex and involve multiple types of regulatory cell death, including ferroptosis, apoptosis, and autophagy. Thus, we aimed to identify the mechanisms underlying MIRI and validate the protective role of epigallocatechin-3-gallate (EGCG) and its related mechanisms in MIRI. An in vivo and in vitro models of MIRI were constructed. The results showed that pretreatment with EGCG could attenuate MIRI, as indicated by increased cell viability, reduced lactate dehydrogenase (LDH) activity and apoptosis, inhibited iron overload, abnormal lipid metabolism, preserved mitochondrial function, decreased infarct size, maintained cardiac function, decreased reactive oxygen species (ROS) level, and reduced TUNEL-positive cells. Additionally, EGCG pretreatment could attenuate ferroptosis, apoptosis, and autophagy induced by MIRI via upregulating 14-3-3η protein levels. Furthermore, the protective effects of EGCG could be abolished with pAd/14-3-3η-shRNA or Compound C11 (a 14-3-3η inhibitor) but not pAd/NC-shRNA. In conclusion, EGCG pretreatment attenuated ferroptosis, apoptosis, and autophagy by mediating 14-3-3η and protected cardiomyocytes against MIRI.

5.
Am J Cancer Res ; 14(3): 1139-1156, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590399

RESUMO

Glioma, the most common primary malignant brain tumor, is characterized by infiltrating immune cells that contribute to tumor progression and therapeutic resistance. Tumor-associated macrophages (TAMs) constitute a significant proportion of these infiltrating immune cells and have been implicated in glioma progression. However, the underlying molecular mechanisms by which TAMs promote glioma progression remain elusive. In this study, we investigated the role of PU.1, a crucial transcription factor involved in myeloid cell development, in glioma-associated macrophage polarization and activation. First, bioinformatics and analysis of clinical glioma samples demonstrated a positive correlation between PU.1 expression in TAMs and disease severity. Further experiments using in vitro coculture systems revealed that the expression of PU.1 is increased in glioma cells vs. control cells. Importantly, PU.1-overexpressing macrophages exhibited a protumorigenic phenotype characterized by enhanced migration, invasion, and proliferation. Mechanistically, we found that PU.1-induced activation of the Bruton tyrosine kinase (BTK) signaling pathway led to Akt/mTOR pathway activation in macrophages, which further enhanced their protumorigenic functions. Furthermore, pharmacological inhibition of the BTK or Akt/mTOR pathway reversed the protumorigenic effects of macrophages in vitro and impaired their ability to promote glioma progression in vivo. In conclusion, our study elucidates a novel mechanism by which PU.1 induces the polarization and activation of TAMs in the glioma microenvironment. We highlight the significance of BTK-mediated Akt/mTOR pathway activation in driving the protumorigenic functions of TAMs. Targeting PU.1 and its downstream signaling pathways in TAMs may provide a promising therapeutic strategy to suppress glioma progression and improve patient outcomes.

6.
J Mater Chem B ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38595070

RESUMO

The past few decades have witnessed substantial progress in biomedical materials for addressing health concerns and improving disease therapeutic and diagnostic efficacy. Conventional biomedical materials are typically created through an ex vivo approach and are usually utilized under physiological environments via transfer from preparative media. This transfer potentially gives rise to challenges for the efficient preservation of the bioactivity and implementation of theranostic goals on site. To overcome these issues, the in situ synthesis of biomedical materials on site has attracted great attention in the past few years. Peptides, which exhibit remarkable biocompability and reliable noncovalent interactions, can be tailored via tunable assembly to precisely create biomedical materials. In this review, we summarize the progress in the self-assembly of peptides in living cells for disease diagnosis and therapy. After a brief introduction to the basic design principles of peptide assembly systems in living cells, the applications of peptide assemblies for bioimaging and disease treatment are highlighted. The challenges in the field of peptide self-assembly in living cells and the prospects for novel peptide assembly systems towards next-generation biomaterials are also discussed, which will hopefully help elucidate the great potential of peptide assembly in living cells for future healthcare applications.

7.
Eur J Pharmacol ; 971: 176524, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38561102

RESUMO

The present study aimed to explore how resveratrol (Res) confers myocardial protection by attenuating ferroptosis. In vivo and in vitro myocardial ischemia/reperfusion injury (MIRI) models were established, with or without Res pretreatment. The results showed that Res pretreatment effectively attenuated MIRI, as evidenced by increased cell viability, reduced lactate dehydrogenase activity, decreased infarct size, and maintained cardiac function. Moreover, Res pretreatment inhibited MIRI-induced ferroptosis, as shown by improved mitochondrial integrity, increased glutathione level, decreased prostaglandin-endoperoxide synthase 2 level, inhibited iron overload, and abnormal lipid peroxidation. Of note, Res pretreatment decreased or increased voltage-dependent anion channel 1/glutathione peroxidase 4 (VDAC1/GPX4) expression, which was increased or decreased via anoxia/reoxygenation (A/R) treatment, respectively. However, the overexpression of VDAC1 via pAd/VDAC1 and knockdown of GPX4 through Si-GPX4 reversed the protective effect of Res in A/R-induced H9c2 cells, whereas the inhibition of GPX4 with RSL3 abolished the protective effect of Res on mice treated with ischemia/reperfusion.Interestingly, knockdown of VDAC1 by Si-VDAC1 promoted the protective effect of Res on A/R-induced H9c2 cells and the regulation of GPX4. Finally, the direct interaction between VDAC1 and GPX4 was determined using co-immunoprecipitation. In conclusion, Res pretreatment could protect the myocardium against MIRI-induced ferroptosis via the VDAC1/GPX4 signaling pathway.


Assuntos
Ferroptose , Traumatismo por Reperfusão Miocárdica , Animais , Camundongos , Miócitos Cardíacos , Resveratrol/farmacologia , Canal de Ânion 1 Dependente de Voltagem , Isquemia , Hipóxia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Reperfusão
8.
Front Med ; 18(1): 19-30, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38561563

RESUMO

The pneumonia caused by novel coronavirus SARS-CoV-2 infection in early December 2019, which was later named coronavirus disease 2019 (COVID-19) by the World Health Organization (WHO), rapidly spread across the world. China has made extraordinary efforts to this unprecedented pandemic, put its response and control at a very high level of infectious disease management (Category B but with measures for Category A), given top priority to the people and their lives, and balanced the pandemic control and socio-economic development. After more than three years' fighting against this disease, China downgraded the management of COVID-19 to Category B infectious disease on January 8, 2023 and the WHO declared the end of public health emergency on May 5, 2023. However, the ending of pandemic does not mean that the disease is no longer a health threat. Experiences against COVID-19 from China and the whole world should be learned to prepare well for the future public health emergencies. This article gives a systematic review of the trajectory of COVID-19 development in China, summarizes the critical policy arrangements and provides evidence for the adjustment during policy making process, so as to share experiences with international community and contribute to the global health for all humanity.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Saúde Pública , Organização Mundial da Saúde , China/epidemiologia
11.
Int J Mol Med ; 53(5)2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577949

RESUMO

Several studies have shown that berberine (BBR) is effective in protecting against myocardial ischemia­reperfusion injury (MI/RI). However, the precise molecular mechanism remains elusive. The present study observed the mechanism and the safeguarding effect of BBR against hypoxia/reoxygenation (H/R) myocardial injury in H9c2 cells. BBR pretreatment significantly improved the decrease of cell viability, P62 protein, Rho Family GTPase 3 (RhoE) protein, ubiquinone subunit B8 protein, ubiquinol­cytochrome c reductase core protein U, the Bcl­2­associated X protein/B­cell lymphoma 2 ratio, glutathione (GSH) and the GSH/glutathione disulphide (GSSG) ratio induced by H/R, while reducing the increase in lactate dehydrogenase, microtubule­associated protein 1 light 3 protein, caspase­3 activity, reactive oxygen species, GSSG and malonaldehyde caused by H/R. Transmission electron microscopy and LysoTracker Red DND­99 staining results showed that BBR pretreatment inhibited H/R­induced excessive autophagy by mediating RhoE. BBR also inhibited mitochondrial permeability transition, maintained the stability of the mitochondrial membrane potential, reduced the apoptotic rate, and increased the level of caspase­3. However, the protective effects of BBR were attenuated by pAD/RhoE­small hairpin RNA, rapamycin (an autophagy activator) and compound C (an AMP­activated protein kinase inhibitor). These new findings suggested that BBR protects the myocardium from MI/RI by inhibiting excessive autophagy, maintaining mitochondrial function, improving the energy supply and redox homeostasis, and attenuating apoptosis through the RhoE/AMP­activated protein kinase pathway.


Assuntos
Proteínas Quinases Ativadas por AMP , Autofagia , Berberina , Traumatismo por Reperfusão Miocárdica , Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose , Berberina/farmacologia , Caspase 3/metabolismo , Dissulfeto de Glutationa/metabolismo , Isquemia/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/etiologia , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Animais , Ratos
12.
Phytomedicine ; 128: 155365, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38552436

RESUMO

BACKGROUND: Ferroptosis, a form of regulated cell death (RCD) that relies on excessive reactive oxygen species (ROS) generation, Fe2+accumulation, abnormal lipid metabolism and is involved in various organ ischemia/reperfusion (I/R) injury, expecially in myocardium. Mitochondria are the powerhouses of eukaryotic cells and essential in regulating multiple RCD. However, the links between mitochondria and ferroptosis are still poorly understood. Salidroside (Sal), a natural phenylpropanoid glycoside isolated from Rhodiola rosea, has mult-bioactivities. However, the effects and mechanism in alleviating ferroptosis caused by myocardial I/R injury remains unclear. PURPOSE: This study aimed to investigate whether pretreated with Sal could protect the myocardium against I/R damage and the underlying mechanisms. In particular, the relationship between Sal pretreatment, AMPKα2 activity, mitochondria and ROS generation was explored. STUDY DESIGN AND METHODS: Firstly, A/R or I/R injury models were employed in H9c2 cells and Sprague-Dawley rats. And then the anti-ferroptotic effects and mechanism of Sal pretreatment was detected using multi-relevant indexes in H9c2 cells. Further, how does Sal pretreatment in AMPKα2 phosphorylation was explored. Finally, these results were validated by I/R injury in rats. RESULTS: Similar to Ferrostatin-1 (a ferroptosis inhibitor) and MitoTEMPO, a mitochondrial free radical scavenger, Sal pretreatment effectively alleviated Fe2+ accumulation, redox disequilibrium and maintained mitochondrial energy production and function in I/R-induced myocardial injury, as demonstrated using multifunctional, enzymatic, and morphological indices. However, these effects were abolished by downregulation of AMPKα2 using an adenovirus, both in vivo and in vitro. Moreover, the results also provided a non-canonical mechanism that, under mild mitochondrial ROS generation, Sal pretreatment upregulated and phosphorylated AMPKα2, which enhanced mitochondrial complex I activity to activate innate adaptive responses and increase cellular tolerance to A/R injury. CONCLUSION: Overall, our work highlighted mitochondria are of great impotance in myocardial I/R-induced ferroptosis and demonstrated that Sal pretreatment activated AMPKα2 against I/R injury, indicating that Sal could become a candidate phytochemical for the treatment of myocardial I/R injury.

13.
Int J Nanomedicine ; 19: 2611-2623, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505166

RESUMO

Background: The photodynamic therapy (PDT) showed promising potential in treating tongue squamous cell carcinoma (TSCC). The Food and Drug Administration approved Verteporfin (Ver) is a powerful alternative in this field for its penetrating power and high production of reactive oxygen species (ROS). However, its applications in the treatment of TSCC are still rare. Methods: Ver was loaded onto Poly (lactic-co-glycolic acid) (PLGA) nanoparticles, followed by the modification with RGD peptide as the ligand. The nanostructured was named as RPV. In vitro assessments were conducted to evaluate the cytotoxicity of RPV through the Live/Dead assay analysis and Cell Counting Kit-8 (CCK-8) assay. Using the reactive oxygen species assay kit, the potential for inducing targeted tumor cell death upon laser irradiation by promoting ROS production was investigated. In vivo experiments involved with the biological distribution of RPV, the administration with RPV followed by laser irradiation, and the measurement of the tumor volumes. Immunohistochemical analysis was used to detect the Ki-67 expression, and apoptosis induced by RPV-treated group. Systemic toxicity was evaluated through hematoxylin-eosin staining and blood routine analysis. Real-time monitoring was employed to track RPV accumulation at tumor sites. Results: The in vitro assessments demonstrated the low cytotoxicity of RPV and indicated its potential for targeted killing TSCC cells under laser irradiation. In vivo experiments revealed significant tumor growth inhibition with RPV treatment and laser irradiation. Immunohistochemical analysis showed a notable decrease in Ki-67 expression, suggesting the effective suppression of cell proliferation, and TUNEL assay indicated the increased apoptosis in the RPV-treated group. Pathological examination and blood routine analysis revealed no significant systemic toxicity. Real-time monitoring exhibited selective accumulation of RPV at tumor sites. Conclusion: The findings collectively suggest that RPV holds promise as a safe and effective therapeutic strategy for TSCC, offering a combination of targeted drug delivery with photodynamic therapy.


Assuntos
Carcinoma de Células Escamosas , Nanopartículas , Fotoquimioterapia , Neoplasias da Língua , Humanos , Verteporfina/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Neoplasias da Língua/tratamento farmacológico , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia , Espécies Reativas de Oxigênio/metabolismo , Antígeno Ki-67 , Linhagem Celular Tumoral , Língua/metabolismo , Língua/patologia , Fármacos Fotossensibilizantes
14.
Interact J Med Res ; 13: e43585, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526532

RESUMO

BACKGROUND: The novel coronavirus SARS-CoV-2 caused the global COVID-19 pandemic. Emerging reports support lower mortality and reduced case numbers in highland areas; however, comparative studies on the cumulative impact of environmental factors and viral genetic diversity on COVID-19 infection rates have not been performed to date. OBJECTIVE: The aims of this study were to determine the difference in COVID-19 infection rates between high and low altitudes, and to explore whether the difference in the pandemic trend in the high-altitude region of China compared to that of the lowlands is influenced by environmental factors, population density, and biological mechanisms. METHODS: We examined the correlation between population density and COVID-19 cases through linear regression. A zero-shot model was applied to identify possible factors correlated to COVID-19 infection. We further analyzed the correlation of meteorological and air quality factors with infection cases using the Spearman correlation coefficient. Mixed-effects multiple linear regression was applied to evaluate the associations between selected factors and COVID-19 cases adjusting for covariates. Lastly, the relationship between environmental factors and mutation frequency was evaluated using the same correlation techniques mentioned above. RESULTS: Among the 24,826 confirmed COVID-19 cases reported from 40 cities in China from January 23, 2020, to July 7, 2022, 98.4% (n=24,430) were found in the lowlands. Population density was positively correlated with COVID-19 cases in all regions (ρ=0.641, P=.003). In high-altitude areas, the number of COVID-19 cases was negatively associated with temperature, sunlight hours, and UV index (P=.003, P=.001, and P=.009, respectively) and was positively associated with wind speed (ρ=0.388, P<.001), whereas no correlation was found between meteorological factors and COVID-19 cases in the lowlands. After controlling for covariates, the mixed-effects model also showed positive associations of fine particulate matter (PM2.5) and carbon monoxide (CO) with COVID-19 cases (P=.002 and P<.001, respectively). Sequence variant analysis showed lower genetic diversity among nucleotides for each SARS-CoV-2 genome (P<.001) and three open reading frames (P<.001) in high altitudes compared to 300 sequences analyzed from low altitudes. Moreover, the frequencies of 44 nonsynonymous mutations and 32 synonymous mutations were significantly different between the high- and low-altitude groups (P<.001, mutation frequency>0.1). Key nonsynonymous mutations showed positive correlations with altitude, wind speed, and air pressure and showed negative correlations with temperature, UV index, and sunlight hours. CONCLUSIONS: By comparison with the lowlands, the number of confirmed COVID-19 cases was substantially lower in high-altitude regions of China, and the population density, temperature, sunlight hours, UV index, wind speed, PM2.5, and CO influenced the cumulative pandemic trend in the highlands. The identified influence of environmental factors on SARS-CoV-2 sequence variants adds knowledge of the impact of altitude on COVID-19 infection, offering novel suggestions for preventive intervention.

15.
Food Res Int ; 182: 114149, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519161

RESUMO

The effects of cysteine (Cys), glutathione (GSH) and cystine (GCys) on sulfides and meaty aroma were studied based on concentration monitoring and metabolomics. In multi-component models, Cys and GSH demonstrated a greater capacity to decrease dimethyl trisulfide (DMTS) levels and increase the proportion of 2-methyl-3-furanthiol (MFT), compared with GCys. Moreover, no discernible difference between Cys and GSH in dynamic profiles of volatiles to further analyze the synergistic effect of both. Results of single factor experiment and optimization revealed that the optimal thermal processing was a second-order thermal procedure. Aroma profiles revealed that the addition of Cys and GSH mixture increased the meaty intensity during the optimal thermal processing. Metabolomics based on Encyclopedia of Genes and Genomes pathway annotation confirmed that Cys and GSH significantly affected the degradation of methionine and thiamine in amino acid and protein metabolic pathways, resulting in various amounts of DMTS and MFT. Research on effect and potentially metabolic mechanisms revealed that the combination of Cys and GSH at ratio of 3:7 had higher and more effective control capacity for free radical reaction of sulfides than either one alone during second-order thermal processing, which would lay theoretical foundation for the development of high-quality thermal process products.


Assuntos
Cisteína , Odorantes , Cisteína/metabolismo , Glutationa/metabolismo , Cistina , Sulfetos
16.
Biomed Pharmacother ; 173: 116413, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461687

RESUMO

Myocardial fibrosis is a significant pathological basis of heart failure. Overactivation of the ERK1/2 and JNK1/2 signaling pathways of MAPK family members synergistically promotes the proliferation of myocardial fibroblasts and accelerates the development of myocardial fibrosis. In addition to some small molecule inhibitors and Western drugs, many Chinese medicines can also inhibit the activity of ERK1/2 and JNK1/2, thus slowing down the development of myocardial fibrosis, and are generally safe and effective. However, the specific biological mechanisms of ERK1/2 and JNK1/2 signaling pathways in myocardial fibrosis still need to be fully understood, and there is no systematic review of existing drugs and methods to inhibit them from improving myocardial fibrosis. This study aims to summarize the roles and cross-linking mechanisms of ERK1/2 and JNK1/2 signaling pathways in myocardial fibrosis and to systematically sort out the small-molecule inhibitors, Western drugs, traditional Chinese medicines, and non-pharmacological therapies that inhibit ERK1/2 and JNK1/2 to alleviate myocardial fibrosis. In the future, we hope to conduct more in-depth research from the perspective of precision-targeted therapy, using this as a basis for developing new drugs that provide new perspectives on the prevention and treatment of heart failure.


Assuntos
Insuficiência Cardíaca , Sistema de Sinalização das MAP Quinases , Humanos , Transdução de Sinais , Insuficiência Cardíaca/tratamento farmacológico , Miocárdio , Fibrose
17.
BMJ Open ; 14(3): e071513, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38448067

RESUMO

OBJECTIVES: This study sought to examine the relationship between Toxoplasma gondii seropositivity and cognitive function in older adults. DESIGN: An observational cross-sectional study. SETTING: The National Health and Nutrition Examination Survey (NHANES) study took place at participants' homes and mobile examination centres. PARTICIPANTS: A total of 2956 older adults aged 60 and above from the NHANES from 2011 to 2014 were included in the study. Exposure of interest: participants had serum Toxoplasma gondii antibody analysed in the laboratory. A value>33 IU/mL was categorised as seropositive for Toxoplasma gondii infection; <27 IU/mL was categorised as seronegative for Toxoplasma gondii infection. PRIMARY AND SECONDARY OUTCOME MEASURES: Cognitive tests included the Consortium to Establish a Registry for Alzheimer's Disease Word Learning subtest (CERAD-WL) for immediate and delayed memory, the Animal Fluency Test (AFT), and the Digit Symbol Substitution Test (DSST). RESULTS: About half of the 2956 participants (mean age 70.0) were female (51.0%), non-Hispanic White (48.3%), and completed some college or above (48.3%). A total of 703 participants were positive for Toxoplasma gondii infection (23.8%). Adjusted linear regression showed that compared with participants with negative Toxoplasma gondii infection, those with positive Toxoplasma gondii infection had lower CERAD-WL immediate memory (beta (ß) -0.16, 95% CI -0.25 to -0.07), CERAD-WL delayed memory (ß -0.15, 95% CI -0.24 to -0.06), AFT (ß -0.15, 95% CI -0.24 to -0.06), DSST (ß -0.34, 95% CI -0.43 to -0.26), and global cognition (ß -0.24, 95% CI -0.32 to -0.16) z-scores after controlling for the covariates. CONCLUSIONS: Toxoplasma gondii seropositivity is associated with worse immediate and delayed verbal learning, language proficiency, executive functioning, processing speed, sustained attention, working memory, as well as global cognition in older adults. Public health measures aiming at preventing Toxoplasma gondii infection may help preserve cognitive functioning in older adults.


Assuntos
Doença de Alzheimer , Toxoplasma , Toxoplasmose , Animais , Feminino , Humanos , Idoso , Masculino , Estudos Transversais , Inquéritos Nutricionais , Cognição , Toxoplasmose/epidemiologia
18.
Neuropharmacology ; 251: 109905, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38521229

RESUMO

Oxidative stress plays important roles in the pathogenesis of early brain injury (EBI) after subarachnoid hemorrhage (SAH). Tat-NR2B9c has shown efficacy as a neuroprotective agent in several studies. Here, we identified the neuroprotective role of Tat-NR2B9c after SAH and its related mechanisms. The results showed that Tat-NR2B9c treatment attenuated oxidative stress, therefore alleviated neuronal apoptosis and neurological deficits after SAH. Tat-NR2B9c treatment could alleviate mitochondrial vacuolization induced by SAH. Compared to SAH + vehicle group, Tat-NR2B9c resulted in the decrease of Acetylated superoxide dismutase2 (Ac-SOD2), Bcl-2-associated X protein (Bax) and cleaved-caspase3 (CC3) protein expression, and the up-regulation of Sirtunin 3 (Sirt3) and Bcl-2 protein level. Moreover, Tat-NR2B9c attenuated excitotoxicity by inhibiting the interaction of PSD95-NR2B-nNOS. Our results demonstrated that Tat-NR2B9c inhibited oxidative stress via inhibition of PSD95-NR2B-nNOS complex formation after SAH. Tat-NR2B9c may serve as a potential treatment for SAH induced brain injury.


Assuntos
Lesões Encefálicas , Fármacos Neuroprotetores , Hemorragia Subaracnóidea , Ratos , Animais , Hemorragia Subaracnóidea/tratamento farmacológico , Estresse Oxidativo , Peptídeos/farmacologia , Lesões Encefálicas/metabolismo , Fármacos Neuroprotetores/farmacologia , Apoptose
19.
Mikrochim Acta ; 191(4): 181, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446252

RESUMO

Silica nanoparticles (SiNPs) with a chemically modified surface typically have a complicated chemical composition, which can significantly differ from their intended design. In this study, we systematically studied the effects of two surface modification methods on active-targeting of intracellular organelles of SiNPs: (1) the widely used step-by-step approach, which involves modifying SiNPs in two steps, i.e., the outer surface of SiNPs was firstly modified with amino groups and then these amino groups were linked with targeting groups, and (2) a newly developed one-step approach in which the ligand-silane complex is initially synthesized, followed by chemically immobilizing the complex on the surface of SiNPs. In the one-step approach, the molar ratio of reactants was precisely tuned so that there are no reactive groups left on the outer surface of SiNPs. Two essential organelles, mitochondria and the nucleus, were selected to compare the targeting performances of SiNPs synthesized via these two approaches. By characterizing physicochemical properties, including structural properties, the number of amino groups, surface charge, polydispersity, and cell colocalization, we demonstrated that SiNPs synthesized via the one-step approach with no residual linkage groups on their surface showed significantly improved mitochondria- and nucleus-targeting performances. This precise control of surface properties allows for optimized biological behavior and active-targeting efficiency of SiNPs. We anticipate that such simple and efficient synthetic strategies will enable the synthesis of effective SiNPs for active-targeting organelles in various biological applications.


Assuntos
Mitocôndrias , Nanopartículas , Corantes , Silanos , Dióxido de Silício
20.
Clin Nucl Med ; 49(5): 409-418, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465929

RESUMO

PURPOSE: In this study, we evaluated and compared the diagnostic performances of 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT for primary and metastatic cholangiocarcinoma (CCA) lesions. We also investigated the performance of PET/MR for visualizing and characterizing CCA and liver metastasis lesions. PATIENTS AND METHODS: Forty-four patients with suspected CCA were recruited and underwent 68 Ga-FAPI-04 and 18 F-FDG PET/CT within 1 week, including 30 patients who underwent simultaneous abdominal 68 Ga-FAPI-04 PET/MR scanning. The findings were confirmed by histopathology or radiographic follow-up. RESULTS: Compared with 18 F-FDG PET/CT, 68 Ga-FAPI-04 PET/CT showed higher sensitivity (94.3% vs 88.6%) and the same accuracy (86.4% vs 86.4%) in evaluating primary tumors. However, its specificity was lower (55.6% vs 77.8%). 68 Ga-FAPI-04 PET was superior to 18 F-FDG PET in both patient-based and lesion-based evaluations except for metastatic lesions in the liver and bone. For intrahepatic CCA, 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT (100% vs 100%) had similar detection rates, with similar uptake levels between tracers ( P > 0.05). However, for extrahepatic CCA, 68 Ga-FAPI-04 PET/CT had a higher detection rate (89.5% vs 78.9%), and 68 Ga-FAPI-04 had a higher uptake ( P < 0.05). PET/MR was more effective than PET/CT in terms of lesion conspicuity and diagnostic confidence for primary tumors and liver metastases. In addition, multisequence MRI identified more liver metastases than 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT. CONCLUSIONS: Compared with 18 F-FDG PET/CT, 68 Ga-FAPI-04 PET/CT showed a higher sensitivity in detecting primary CCA tumors, involved lymph nodes, and peritoneal metastases. Compared with 68 Ga-FAPI-04 PET/CT, PET/MR detected primary and liver metastatic lesions more accurately. For extrahepatic CCA, the combination of 68 Ga-FAPI-04 PET/CT and abdominal PET/MRI may replace 18 F-FDG PET/CT.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neoplasias Hepáticas , Quinolinas , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Peritônio , Colangiocarcinoma/diagnóstico por imagem , Radioisótopos de Gálio , Imageamento por Ressonância Magnética , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos
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