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1.
Nat Rev Neurosci ; 24(11): 655-671, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37730910

RESUMO

Most animals live under constant threat from predators, and predation has been a major selective force in shaping animal behaviour. Nevertheless, defence responses against predatory threats need to be balanced against other adaptive behaviours such as foraging, mating and recovering from infection. This behavioural balance in ethologically relevant contexts requires adequate integration of internal and external signals in a complex interplay between the brain and the body. Despite this complexity, research has often considered defensive behaviour as entirely mediated by the brain processing threat-related information obtained via perception of the external environment. However, accumulating evidence suggests that the endocrine, immune, gastrointestinal and reproductive systems have important roles in modulating behavioural responses to threat. In this Review, we focus on how predatory threat defence responses are shaped by threat imminence and review the circuitry between subcortical brain regions involved in mediating defensive behaviours. Then, we discuss the intersection of peripheral systems involved in internal states related to infection, hunger and mating with the neurocircuits that underlie defence responses against predatory threat. Through this process, we aim to elucidate the interconnections between the brain and body as an integrated network that facilitates appropriate defensive responses to threat and to discuss the implications for future behavioural research.


Assuntos
Comportamento Animal , Comportamento Predatório , Animais , Adaptação Psicológica , Encéfalo
2.
Nano Lett ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856118

RESUMO

Copper-based catalysts have been attracting increasing attention for CO2 electroreduction into value-added multicarbon chemicals. However, most Cu-based catalysts are designed for ethylene production, while ethanol production with high Faradaic efficiency at high current density still remains a great challenge. Herein, Cu clusters supported on single-atom Cu dispersed nitrogen-doped carbon (Cux/Cu-N/C) show ethanol Faradaic efficiency of ∼40% and partial current density of ∼350 mA cm-2. Quasi in situ X-ray photoelectron spectroscopy and operando X-ray absorption spectroscopy results suggest the generation of surface asymmetrical sites of Cu+ and Cu0 as well as Cu clusters by electrochemical reduction and reconstruction during the CO2 electroreduction process. Density functional theory calculations indicate that the interaction between Cu clusters and the Cu-N/C support enhances *CO adsorption, facilitates the C-C coupling step, and favors the hydrogenation rather than dehydroxylation of the critical intermediate *CHCOH toward ethanol in the bifurcation.

3.
Small ; 20(14): e2306446, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38105592

RESUMO

Copper-based nanozymes exhibit excellent antitumor activity but are easily inactivated due to the disturbance of proteins or other macromolecules with sulfhydryl. A tumor microenvironment-responsive CuMnO@Fe3O4 (CMF) core-shell nanozyme for highly efficient tumor theranostics is developed. A platelet-derived growth factor receptor-ß-recognizing cyclic peptide (PDGFB) target is conjugated to the surface of CMF to fabricate a tumor-specific nanozyme (PCMF). The core-shell nanostructure significantly avoids the oxidation and inactivation of copper-based nanozyme, promoting the antitumor activity of PCMF. The weak acid- and GSH-activated T1 and T2 relaxation rate of PCMF contributes to T1 and T2 dual contrast imaging at the tumor site. In addition, the PCMF disintegrates and produces some metal ions that possess Fenton catalytic activity (i.e., Cu+, Mn2+, and Fe2+) under TME. This process significantly depletes GSH, accelerates Fenton and Fenton-like reactions, enhances cellular reactive oxygen species (ROS) levels, and induces cancer cell apoptosis and ferroptosis. PCMF also exhibits photothermal functions, so it can be used in combined photothermal therapy, ferroptosis therapy, and chemodynamic therapy, improving anticancer activity. This work provides insights into the design of an exquisite nanostructure for high-sensitive and tumor-specific theranostics.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Medicina de Precisão , Cobre , Microambiente Tumoral , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Peróxido de Hidrogênio , Linhagem Celular Tumoral
5.
Mol Psychiatry ; 28(9): 3751-3759, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37848709

RESUMO

Pupillary response, an important process in visual perception and social and emotional cognition, has been widely studied for understanding the neural mechanisms of neuropsychiatric disorders. However, there have been few studies on pupil response to social and non-social stimuli in animal models of neurodevelopmental disorders including autism spectrum disorder (ASD) and attention deficit hyperactivity disorder. Here, we developed a pupilometer using a robust eye feature-detection algorithm for real-time pupillometry in dogs. In a pilot study, we found that a brief light flash induced a less-pronounced and slower pupil dilation response in gene-edited dogs carrying mutations in Shank3; mutations of its ortholog in humans were repeatedly identified in ASD patients. We further found that obnoxious, loud firecracker sound of 120 dB induced a stronger and longer pupil dilation response in Shank3 mutant dogs, whereas a high reward food induced a weaker pupillary response in Shank3 mutants than in wild-type control dogs. In addition, we found that Shank3 mutants showed compromised pupillary synchrony during dog-human interaction. These findings of altered pupil response in Shank3 mutant dogs recapitulate the altered sensory responses in ASD patients. Thus, this study demonstrates the validity and value of the pupilometer for dogs, and provides an effective paradigm for studying the underlying neural mechanisms of ASD and potentially other psychiatric disorders.


Assuntos
Transtorno do Espectro Autista , Humanos , Cães , Animais , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/psicologia , Pupila/fisiologia , Projetos Piloto , Emoções , Modelos Animais de Doenças
6.
J Nanobiotechnology ; 22(1): 34, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38238748

RESUMO

Severe tissue injuries pose a significant risk to human health. Conventional wound dressings fall short in achieving effective tissue regeneration, resulting in suboptimal postoperative healing outcomes. In this study, an asymmetric adhesive wound dressing (marked as SIS/PAA/LAP) was developed, originating from acrylate acid (AA) solution with laponite (LAP) nanoparticles polymerization and photo-crosslinked on the decellularized extracellular matrix small intestinal submucosa (SIS) patch. Extensive studies demonstrated that the SIS/PAA/LAP exhibited higher tissue adhesion strength (~ 33 kPa) and burst strength (~ 22 kPa) compared to conventional wound dressings like Tegaderm and tissue adhesive products. Importantly, it maintained favorable cell viability and demonstrated robust angiogenic capacity. In animal models of full-thickness skin injuries in rats and skin injuries in Bama miniature pigs, the SIS/PAA/LAP could be precisely applied to wound sites. By accelerating the formation of tissue vascularization, it displayed superior tissue repair outcomes. This asymmetrically adhesive SIS-based patch would hold promising applications in the field of wound dressings.


Assuntos
Adesivos , Cicatrização , Humanos , Ratos , Animais , Suínos , Adesivos/farmacologia , Pele , Bandagens
7.
Neuroimage ; 280: 120331, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37604295

RESUMO

Designing a transcranial electrical stimulation (tES) strategy requires considering multiple objectives, such as intensity in the target area, focality, stimulation depth, and avoidance zone. These objectives are often mutually exclusive. In this paper, we propose a general framework, called multi-objective optimization via evolutionary algorithm (MOVEA), which solves the non-convex optimization problem in designing tES strategies without a predefined direction. MOVEA enables simultaneous optimization of multiple targets through Pareto optimization, generating a Pareto front after a single run without manual weight adjustment and allowing easy expansion to more targets. This Pareto front consists of optimal solutions that meet various requirements while respecting trade-off relationships between conflicting objectives such as intensity and focality. MOVEA is versatile and suitable for both transcranial alternating current stimulation (tACS) and transcranial temporal interference stimulation (tTIS) based on high definition (HD) and two-pair systems. We comprehensively compared tACS and tTIS in terms of intensity, focality, and steerability for targets at different depths. Our findings reveal that tTIS enhances focality by reducing activated volume outside the target by 60%. HD-tTIS and HD-tDCS can achieve equivalent maximum intensities, surpassing those of two-pair tTIS, such as 0.51 V/m under HD-tACS/HD-tTIS and 0.42 V/m under two-pair tTIS for the motor area as a target. Analysis of variance in eight subjects highlights individual differences in both optimal stimulation policies and outcomes for tACS and tTIS, emphasizing the need for personalized stimulation protocols. These findings provide guidance for designing appropriate stimulation strategies for tACS and tTIS. MOVEA facilitates the optimization of tES based on specific objectives and constraints, advancing tTIS and tACS-based neuromodulation in understanding the causal relationship between brain regions and cognitive functions and treating diseases. The code for MOVEA is available at https://github.com/ncclabsustech/MOVEA.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Humanos , Encéfalo , Cognição , Algoritmos , Evolução Biológica
8.
Small ; 19(25): e2300856, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36932891

RESUMO

CO2 electrolysis is a promising route for achieving net-zero emission through decarbonization. To realize CO2 electrolysis toward practical application, beyond catalyst structures, it is also critical to rationally manipulate catalyst microenvironments such as the water at the electrode/electrolyte interface. Here, the role of interfacial water in CO2 electrolysis over Ni-N-C catalyst modified with different polymers is investigated. Benefiting from a hydrophilic electrode/electrolyte interface, the Ni-N-C catalyst modified with quaternary ammonia poly(N-methyl-piperidine-co-p-terphenyl) shows a Faradaic efficiency of 95% and a partial current density of 665 mA cm-2 for CO production in an alkaline membrane electrode assembly electrolyzer. A scale-up demonstration using a 100 cm2 electrolyzer achieves a CO production rate of 514 mL min-1 at a current of 80 A. In-situ microscopy and spectroscopy measurements indicate that the hydrophilic interface significantly promotes the formation of the *COOH intermediate, rationalizing the high CO2 electrolysis performance.

9.
Lipids Health Dis ; 22(1): 95, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403063

RESUMO

BACKGROUND: Dyslipidemia and inflammation are significant factors for the onset of cardiovascular diseases (CVD); however, studies regarding their interactions on the risk of CVD are scarce. This study aimed to assess the interaction of dyslipidemia and high-sensitivity C-reactive protein (hs-CRP) on CVD. METHODS: This prospective cohort enrolled 4,128 adults at baseline in 2009 and followed them up until May 2022 for collecting CVD events. Cox-proportional hazard regression analysis estimated the hazard ratios (HRs) and 95% confidence intervals (CIs) of the associations of increased hs-CRP (≥ 1 mg/L) and dyslipidemia with CVD. The additive interactions were explored using the relative excess risk of interaction (RERI) and the multiplicative interactions were assessed with HRs (95% CI) while the multiplicative interactions were assessed by the HRs (95% CI) of interaction terms. RESULTS: The HRs of the association between increased hs-CRP and CVD were 1.42 (95% CI: 1.14-1.79) and 1.17 (95% CI: 0.89-1.53) among subjects with normal lipid levels and subjects with dyslipidemia, respectively. Stratified analyses by hs-CRP levels showed that among participants with normal hs-CRP (< 1 mg/L), TC ≥ 240 mg/dL, LDL-C ≥ 160 mg/dL, non-HDL-C ≥ 190 mg/dL, ApoB < 0.7 g/L, and LDL/HDL-C ≥ 2.02 were associated with CVD [HRs (95%CIs): 1.75 (1.21-2.54), 2.16 (1.37-3.41), 1.95 (1.29-2.97), 1.37 (1.01-1.67), and 1.30 (1.00-1.69), all P < 0.05, respectively]. While in the population with increased hs-CRP, only ApoAI > 2.10 g/L had a significant association with CVD [HR (95% CI): 1.69 (1.14-2.51)]. Interaction analyses showed that increased hs-CRP had multiplicative and additive interactions with LDL-C ≥ 160 mg/dL and non-HDL-C ≥ 190 mg/dL on the risk of CVD [HRs (95%CIs): 0.309 (0.153-0.621), and 0.505 (0.295-0.866); RERIs (95%CIs): -1.704 (-3.430-0.021 and - 0.694 (-1.476-0.089), respectively, all P < 0.05]. CONCLUSION: Overall our findings indicate negative interactions between abnormal blood lipid levels and hs-CRP on the risk of CVD. Further large-scale cohort studies with trajectories measurement of lipids and hs-CRP might verify our results as well explore the biological mechanism behind that interaction.


Assuntos
Doenças Cardiovasculares , Dislipidemias , Adulto , Humanos , Proteína C-Reativa/metabolismo , Estudos Prospectivos , LDL-Colesterol , Fatores de Risco , Estudos de Coortes , Lipídeos
10.
BMC Biol ; 20(1): 281, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522765

RESUMO

BACKGROUND: Sex differences ranging from physiological functions to pathological disorders are developmentally hard-wired in a broad range of animals, from invertebrates to humans. These differences ensure that animals can display appropriate behaviors under a variety of circumstances, such as aggression, hunting, sleep, mating, and parental care, which are often thought to be important in the acquisition of resources, including territory, food, and mates. Although there are reports of an absence of sexual dimorphism in the context of innate fear, the question of whether there is sexual dimorphism of innate defensive behavior is still an open question. Therefore, an in-depth investigation to determine whether there are sex differences in developmentally hard-wired innate defensive behaviors in life-threatening circumstances is warranted. RESULTS: We found that innate defensive behavioral responses to potentially life-threatening stimuli between males and females were indistinguishable over their lifespan. However, by using 3 dimensional (3D)-motion learning framework analysis, we found that males and females showed different behavioral patterns after escaping to the refuge. Specifically, the defensive "freezing" occurred primarily in males, whereas females were more likely to return directly to exploration. Moreover, there were also no estrous phase differences in innate defensive behavioral responses after looming stimuli. CONCLUSIONS: Our results demonstrate that visually-evoked innate fear behavior is highly conserved throughout the lifespan in both males and females, while specific post-threat coping strategies depend on sex. These findings indicate that innate fear behavior is essential to both sexes and as such, there are no evolutionary-driven sex differences in defensive ability.


Assuntos
Sinais (Psicologia) , Medo , Humanos , Camundongos , Feminino , Masculino , Animais , Medo/fisiologia , Instinto , Caracteres Sexuais , Adaptação Psicológica
11.
Angew Chem Int Ed Engl ; 62(26): e202303327, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37119055

RESUMO

Electrochemical conversion of nitrate (NO3 - ) into ammonia (NH3 ) represents a potential way for achieving carbon-free NH3 production while balancing the nitrogen cycle. Herein we report a high-performance Cu nanosheets catalyst which delivers a NH3 partial current density of 665 mA cm-2 and NH3 yield rate of 1.41 mmol h-1 cm-2 in a flow cell at -0.59 V vs. reversible hydrogen electrode. The catalyst showed a high stability for 700 h with NH3 Faradaic efficiency of ≈88 % at 365 mA cm-2 . In situ spectroscopy results verify that Cu nanosheets are in situ derived from the as-prepared CuO nanosheets under electrochemical NO3 - reduction reaction conditions. Electrochemical measurements and density functional theory calculations indicate that the high performance is attributed to the tandem interaction of Cu(100) and Cu(111) facets. The NO2 - generated on the Cu(100) facets is subsequently hydrogenated on the Cu(111) facets, thus the tandem catalysis promotes the crucial hydrogenation of *NO to *NOH for NH3 production.


Assuntos
Amônia , Nitratos , Catálise , Eletrodos , Hidrogenação
12.
Angew Chem Int Ed Engl ; 62(45): e202309893, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37747793

RESUMO

Electrochemically converting CO2 to valuable chemicals holds great promise for closing the anthropogenic carbon cycle. Owing to complex reaction pathways and shared rate-determining steps, directing the selectivity of CO2 /CO electrolysis to a specific multicarbon product is very challenging. We report here a strategy for highly selective production of acetate from CO electrolysis by constructing metal-organic interfaces. We demonstrate that the Cu-organic interfaces constructed by in situ reconstruction of Cu complexes show very impressive acetate selectivity, with a high Faradaic efficiency of 84.2 % and a carbon selectivity of 92.1 % for acetate production, in an alkaline membrane electrode assembly electrolyzer. The maximum acetate partial current density and acetate yield reach as high as 605 mA cm-2 and 63.4 %, respectively. Thorough structural characterizations, control experiments, operando Raman spectroscopy measurements, and density functional theory calculation results indicate that the Cu-organic interface creates a favorable reaction microenvironment that enhances *CO adsorption, lowers the energy barrier for C-C coupling, and facilitates the formation of CH3 COOH over other multicarbon products, thus rationalizing the selective acetate production.

13.
Mol Psychiatry ; 26(9): 4719-4741, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32555286

RESUMO

The prevailing view is that parvalbumin (PV) interneurons play modulatory roles in emotional response through local medium spiny projection neurons (MSNs). Here, we show that PV activity within the nucleus accumbens shell (sNAc) is required for producing anxiety-like avoidance when mice are under anxiogenic situations. Firing rates of sNAcPV neurons were negatively correlated to exploration time in open arms (threatening environment). In addition, sNAcPV neurons exhibited high excitability in a chronic stress mouse model, which generated excessive maladaptive avoidance behavior in an anxiogenic context. We also discovered a novel GABAergic pathway from the anterior dorsal bed nuclei of stria terminalis (adBNST) to sNAcPV neurons. Optogenetic activation of these afferent terminals in sNAc produced an anxiolytic effect via GABA transmission. Next, we further demonstrated that chronic stressors attenuated the inhibitory synaptic transmission at adBNSTGABA → sNAcPV synapses, which in turn explains the hyperexcitability of sNAc PV neurons on stressed models. Therefore, activation of these GABAergic afferents in sNAc rescued the excessive avoidance behavior related to an anxious state. Finally, we identified that the majority GABAergic input neurons, which innervate sNAcPV cells, were expressing somatostatin (SOM), and also revealed that coordination between SOM- and PV- cells functioning in the BNST → NAc circuit has an inhibitory influence on anxiety-like responses. Our findings provide a potentially neurobiological basis for therapeutic interventions in pathological anxiety.


Assuntos
Interneurônios , Parvalbuminas , Animais , Ansiedade , Neurônios GABAérgicos , Camundongos , Somatostatina
14.
Pharmacol Res ; 185: 106481, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36195307

RESUMO

Coptis Chinensis Franch is widely used in the treatment of diabetes, and berberine is the primary bioactive component in it. Evidence from previous studies has shown that berberine supplementation is effective for treating diabetic nephropathy (DN) in animal models. In this systematic review and meta-analysis, we evaluated the effects and potential mechanisms of action of berberine in animal models of DN. Relevant studies were searched from the English language databases PubMed, Web of Science, and Embase starting from the establishment of the database till June 2022. Twenty-five studies were included, and the risk of bias tool from SYRCLE was used to assess the methodological quality. Statistical analysis was conducted using STATA 15.1. Fasting blood glucose (FBG), blood urea nitrogen (BUN), serum creatinine (SCR), and the kidney index (KI) were the primary outcomes to be analyzed. The overall results showed that berberine improves the indicators of renal function, such as BUN, SCR, proteinuria, and KI. Meanwhile, berberine also improved inflammatory indicators, such as IL-6 and TNF-α, and oxidative stress indicators, such as the superoxide dismutase activity and malondialdehyde content. Additionally, berberine lowered the levels of known risk factors, including triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL). These beneficial effects of berberine in DN may be related to its anti-fibrotic, anti-inflammatory, and anti-oxidative stress properties. However, to assess the anti-diabetic nephropathy effects and safety of berberine in a more accurate manner, additional large-scale, long-term, and high-quality preclinical trials are needed to confirm these findings before clinical application.


Assuntos
Berberina , Diabetes Mellitus , Nefropatias Diabéticas , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Creatinina , Triglicerídeos , LDL-Colesterol , Diabetes Mellitus/tratamento farmacológico
15.
Microb Ecol ; 84(4): 1245-1255, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34757460

RESUMO

The pine wood nematode (PWN), Bursaphelenchus xylophilus, is a destructive invasive species that exerts devastating effects on most native pines in invaded regions, while many of the non-native pines have resistance to PWN. Recently, increasingly more research is focused on how microbial communities can improve host resistance against pathogens. However, the relationship between the microbial community structures and varying levels of pathogen resistance observed in different pine tree species remains unclear. Here, the bacterial and fungal communities of introduced resistant pines Pinus elliottii, P. caribaea, and P. taeda and native susceptible pines healthy and wilted P. massoniana infected by PWN were analyzed. The results showed that 6057 bacterial and 3931 fungal OTUs were annotated. The pine samples shared 944 bacterial OTUs primarily in the phyla Proteobacteria, Acidobacteria, Firmicutes, Bacteroidetes, and Chloroflexi and 111 fungal OTUs primarily in phyla Ascomycota and Basidiomycota, though different pines had unique OTUs. There were significant differences in microbial community diversity between different pines, especially between the bacterial communities of resistant and susceptible pines, and fungal communities between healthy pines (resistant pines included) and the wilted P. massoniana. Resistant pines had a greater abundance of bacteria in the genera Acidothermus (class unidentified_Actinobacteria) and Prevotellaceae (class Alphaproteobacteria), but a lower abundance of Erwinia (class Gammaproteobacteria). Healthy pines had a higher fungal abundance of Cladosporium (class Dothideomycetes) and class Eurotiomycetes, but a lower abundance of Graphilbum, Sporothrix, Geosmithia (class Sordariomycetes), and Cryptoporus (classes Agaricomycetes and Saccharomycetes). These differences in microbial abundance between resistant and healthy pines might be associated with pathogen resistance of the pines, and the results of this study contribute to the studies exploring microbial-based control of PWN.


Assuntos
Microbiota , Nematoides , Pinus , Animais , Pinus/microbiologia , Bactérias/genética , Espécies Introduzidas , Doenças das Plantas
16.
Nutr Metab Cardiovasc Dis ; 32(3): 550-559, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34961647

RESUMO

BACKGROUND AND AIMS: The purpose of this study is to explore the relationship between Chinese visceral adipose index (CVAI) and the risk of coronary heart disease (CHD) in Chinese through a large cohort study. METHODS AND RESULTS: This study included 42,165 adults who were without CHD at baseline and who completed at least one annual follow-up between 2009 and 2016. We used the Cox proportional hazards model to estimate Hazard Ratios (HRs) and 95% Confidence Intervals (CIs) for the association between CVAI and risk of CHD. During the median follow-up of 3.36 years (154,808 person years), 520 participants developed CHD, including 374 males and 146 females. Compared with the first quartile of CVAI, the risk of CHD was significantly increased in the fourth quartile of CVAI in multivariate model (HR [95% CI]: 9.92 [5.45, 18.04], P < 0.001). Sensitivity analysis by excluding incident CHD developed in the first two years of follow-up reinforced our results. Gender stratification analyses showed that the relationship between CVAI and CHD risk was higher in males than that in females. The restricted cubic spline showed a non-linear dose-response relationship between CVAI and CHD risk. In addition, CVAI was associated with CHD risk in the subgroups of participants without T2DM, without hypertension, and without fatty liver. CONCLUSION: CVAI was significantly associated with the risk of CHD. Individuals should keep CVAI at normal level to prevent CHD.


Assuntos
Doença das Coronárias , Obesidade Abdominal , Adulto , China/epidemiologia , Estudos de Coortes , Doença das Coronárias/diagnóstico , Doença das Coronárias/epidemiologia , Feminino , Humanos , Masculino , Fatores de Risco
17.
J Nanobiotechnology ; 20(1): 98, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236363

RESUMO

Iron oxide nanoparticles (IONPs)-based contrast agents are widely used for T2-weighted magnetic resonance imaging (MRI) in clinical diagnosis, highlighting the necessity and importance to evaluate their potential systematic toxicities. Although a few previous studies have documented the toxicity concerns of IONPs to major organs, limited data are available on the potential reproductive toxicity caused by IONPs, especially when administrated via intravenous injection to mimic clinical use of MRI contrast agents. Our study aimed to determine whether exposure to IONPs would affect male reproductive system and cause other related health concerns in ICR mice. The mice were intravenously injected with different concentrations IONPs once followed by routine toxicity tests of major organs and a series of reproductive function-related analyses at different timepoints. As a result, most of the contrast agents were captured by reticuloendothelial system (RES) organs such as liver and spleen, while IONPs have not presented adverse effects on the normal function of these major organs. In contrast, although IONPs were not able to enter testis through the blood testicular barrier (BTB), and they have not obviously impaired the overall testicular function or altered the serum sex hormones levels, IONPs exposure could damage Sertoli cells in BTB especially at a relative high concentration. Moreover, IONPs administration led to a short-term reduction in the quantity and quality of sperms in a dose-dependent manner, which might be attributed to the increase of oxidative stress and apoptotic activity in epididymis. However, the semen parameters have gradually returned to the normal range within 14 days after the initial injection of IONPs. Collectively, these results demonstrated that IONPs could cause reversible damage to the reproductive system of male mice without affecting the main organs, providing new guidance for the clinical application of IONPs as T2-MRI contrast agents.


Assuntos
Meios de Contraste , Compostos Férricos , Animais , Meios de Contraste/toxicidade , Compostos Férricos/toxicidade , Genitália , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos ICR
18.
Inflammopharmacology ; 30(6): 2035-2050, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36227442

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic, potentially cancerous disease with limited treatment options. Quercetin may be a novel treatment for IBD. However, its efficacy and safety are unknown. Our goal was to conduct a systematic evaluation to summarize the preclinical effects of quercetin, which may help guide future studies. METHODS: The literature was drawn from three English databases (PubMed, Embase, and Web of Science), and the quality of the included literature was assessed using the SYRCLE list (10 items). The meta-analysis was performed using STATA 15.1 software. RESULTS: A total of 11 animal studies with 199 animals were involved. The current meta-analysis showed that quercetin could reduce histological score (HS), Disease Activity Index (DAI), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), nitric oxide(NO), malondialdehyde (MDA), myeloperoxidase (MPO) activity and increase colon length (CL), weight change degree (WCD), interleukin-10 (IL-10), glutathione (GSH), superoxide dismutase (SOD) activity and catalase (CAT) activity, which may involve anti-inflammatory, anti-oxidative stress, cytoprotective, barrier protection, flora regulation. CONCLUSIONS: In conclusion, preclinical evidence suggests that quercetin is an ideal agent for IBD treatment. However, the validity of the findings may be compromised by the low methodological quality and the small number of studies included. There may be some discrepancies between the results of the current analysis and the real situation. More rigorous experimental designs and more comprehensive studies are needed to test the protection of quercetin against IBD.


Assuntos
Doenças Inflamatórias Intestinais , Quercetina , Animais , Antioxidantes/metabolismo , Glutationa/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Malondialdeído , Óxido Nítrico , Estresse Oxidativo , Quercetina/farmacologia , Quercetina/uso terapêutico
19.
Angew Chem Int Ed Engl ; 61(40): e202209629, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35909076

RESUMO

The design of efficient copper(Cu)-based catalysts is critical for CO2 electroreduction into multiple carbon products. However, most Cu-based catalysts are favorable for ethylene production while selective production of ethanol with high Faradaic efficiency and current density still remains a great challenge. Herein, we design a carbon-coated CuOx (CuOx @C) catalyst through one-pot pyrolysis of Cu-based metal-organic framework (MOF), which exhibits high selectivity for CO2 electroreduction to ethanol with Faradaic efficiency of 46 %. Impressively, the partial current density of ethanol reaches 166 mA cm-2 , which is higher than that of most reported catalysts. Operando Raman spectra indicate that the carbon coating can efficiently stabilize Cu+ species under CO2 electroreduction conditions, which promotes the C-C coupling step. Density functional theory (DFT) calculations reveal that the carbon layer can tune the key intermediate *HOCCH goes the hydrogenation pathway toward ethanol production.

20.
Angew Chem Int Ed Engl ; 61(5): e202114238, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-34859554

RESUMO

The electrochemical CO2 reduction reaction (CO2 RR) over Cu-based catalysts shows great potential for converting CO2 into multicarbon (C2+ ) fuels and chemicals. Herein, we introduce an A2 M2 O7 structure into a Cu-based catalyst through a solid-state reaction synthesis method. The Cu2 P2 O7 catalyst is electrochemically reduced to metallic Cu with a significant structure evolution from grain aggregates to highly porous structure under CO2 RR conditions. The reconstructed Cu2 P2 O7 catalyst achieves a Faradaic efficiency of 73.6 % for C2+ products at an applied current density of 350 mA cm-2 , remarkably higher than the CuO counterparts. The reconstructed Cu2 P2 O7 catalyst has a high electrochemically active surface area, abundant defects, and low-coordinated sites. In situ Raman spectroscopy and density functional theory calculations reveal that CO adsorption with bridge and atop configurations is largely improved on Cu with defects and low-coordinated sites, which decreased the energy barrier of the C-C coupling reaction for C2+ products.

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