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1.
Proc Natl Acad Sci U S A ; 120(20): e2218739120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155879

RESUMO

Carbon-based nanomaterials (CNMs) have recently been found in humans raising a great concern over their adverse roles in the hosts. However, our knowledge of the in vivo behavior and fate of CNMs, especially their biological processes elicited by the gut microbiota, remains poor. Here, we uncovered the integration of CNMs (single-walled carbon nanotubes and graphene oxide) into the endogenous carbon flow through degradation and fermentation, mediated by the gut microbiota of mice using isotope tracing and gene sequencing. As a newly available carbon source for the gut microbiota, microbial fermentation leads to the incorporation of inorganic carbon from the CNMs into organic butyrate through the pyruvate pathway. Furthermore, the butyrate-producing bacteria are identified to show a preference for the CNMs as their favorable source, and excessive butyrate derived from microbial CNMs fermentation further impacts on the function (proliferation and differentiation) of intestinal stem cells in mouse and intestinal organoid models. Collectively, our results unlock the unknown fermentation processes of CNMs in the gut of hosts and underscore an urgent need for assessing the transformation of CNMs and their health risk via the gut-centric physiological and anatomical pathways.


Assuntos
Microbioma Gastrointestinal , Nanoestruturas , Nanotubos de Carbono , Humanos , Animais , Camundongos , Microbioma Gastrointestinal/fisiologia , Nanotubos de Carbono/efeitos adversos , Fermentação , Butiratos/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(23): e2200363119, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35653569

RESUMO

The nanomaterial­protein "corona" is a dynamic entity providing a synthetic­natural interface mediating cellular uptake and subcellular distribution of nanomaterials in biological systems. As nanomaterials are central to the safe-by-design of future nanomedicines and the practice of nanosafety, understanding and delineating the biological and toxicological signatures of the ubiquitous nanomaterial­protein corona are precursors to the continued development of nano­bio science and engineering. However, despite well over a decade of extensive research, the dynamics of intracellular release or exchange of the blood protein corona from nanomaterials following their cellular internalization remains unclear, and the biological footprints of the nanoparticle­protein corona traversing cellular compartments are even less well understood. To address this crucial bottleneck, the current work screened evolution of the intracellular protein corona along the endocytotic pathway from blood via lysosomes to cytoplasm in cancer cells. Intercellular proteins, including pyruvate kinase M2 (PKM2), and chaperones, displaced some of the initially adsorbed blood proteins from the nanoparticle surface, which perturbed proteostasis and subsequently incited chaperone-mediated autophagy (CMA) to disrupt the key cellular metabolism pathway, including glycolysis and lipid metabolism. Since proteostasis is key to the sustainability of cell function, its collapse and the resulting CMA overdrive spell subsequent cell death and aging. Our findings shed light on the consequences of the transport of extracellular proteins by nanoparticles on cell metabolism.


Assuntos
Nanoestruturas , Coroa de Proteína , Coroa de Proteína/metabolismo , Proteômica , Proteostase , Piruvato Quinase/metabolismo
3.
J Am Chem Soc ; 146(15): 10478-10488, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578196

RESUMO

During biomedical applications, nanozymes, exhibiting enzyme-like characteristics, inevitably come into contact with biological fluids in living systems, leading to the formation of a protein corona on their surface. Although it is acknowledged that molecular adsorption can influence the catalytic activity of nanozymes, there is a dearth of understanding regarding the impact of the protein corona on nanozyme activity and its determinant factors. In order to address this gap, we employed the AuNR@Pt@PDDAC [PDDAC, poly(diallyldimethylammonium chloride)] nanorod (NR) as a model nanozyme with multiple activities, including peroxidase, oxidase, and catalase-mimetic activities, to investigate the inhibitory effects of the protein corona on the catalytic activity. After the identification of major components in the plasma protein corona on the NR, we observed that spherical proteins and fibrous proteins induced distinct inhibitory effects on the catalytic activity of nanozymes. To elucidate the underlying mechanism, we uncovered that the adsorbed proteins assembled on the surface of the nanozymes, forming protein networks (PNs). Notably, the PNs derived from fibrous proteins exhibited a screen mesh-like structure with smaller pore sizes compared to those formed by spherical proteins. This structural disparity resulted in a reduced efficiency for the permeation of substrate molecules, leading to a more robust inhibition in activity. These findings underscore the significance of the protein shape as a crucial factor influencing nanozyme activity. This revelation provides valuable insights for the rational design and application of nanozymes in the biomedical fields.


Assuntos
Nanoestruturas , Coroa de Proteína , Escleroproteínas , Peroxidase , Adsorção , Corantes , Catálise
4.
Rapid Commun Mass Spectrom ; 38(11): e9740, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38567573

RESUMO

RATIONALE: The mass spectra of compounds containing dimethyl (phenyl)silyl group (-SiMe2Ph) sometimes exhibit unusual ion peaks when measured using Orbitrap gas chromatography-mass spectrometry (GC-MS). This would complicate the mass spectra and may limit the matching of spectral data with preexisting resources for compound annotation. These peaks were identified as products from reactions with residual water. METHODS: A series of dimethyl (phenyl)silyl compounds were dissolved in methanol and investigated using Orbitrap GC-MS. Certain ions reacted with residual water in the C-trap. The reaction was confirmed using accurate mass and elemental composition analysis via MS studies, and the active center of the reaction was determined using density functional theory (DFT) calculations. RESULTS: Two types of gas-phase reactions between gaseous water and cations from a series of silanes were identified. DFT calculations indicate that silicon (Si) acts as the active center for these gas-phase water reactions. Compounds with multiple Si atoms generate a larger number of additional ions, which would complicate the mass spectra. The mass spectra of vinylsilanes and alkylsilanes with -SiMe2Ph indicate that the conjugated group linked to -SiMe2Ph can affect the water adduction process. CONCLUSIONS: Silane ions could react with residual water in the C-trap of an Orbitrap mass spectrometer. The mass spectra of these compounds may exhibit unexplained peaks arising from gas-phase reactions. Although these reactions may decrease spectral matching scores for compound annotation, they offer opportunities for systematic investigations into the mechanistic and kinetic aspects of high-energy ion reactivity.

5.
Proc Natl Acad Sci U S A ; 118(44)2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34716267

RESUMO

The rapid development of nanotechnology has greatly benefited modern science and engineering and also led to an increased environmental exposure to nanoparticles (NPs). While recent research has established a correlation between the exposure of NPs and cardiovascular diseases, the intrinsic mechanisms of such a connection remain unclear. Inhaled NPs can penetrate the air-blood barrier from the lung to systemic circulation, thereby intruding the cardiovascular system and generating cardiotoxic effects. In this study, on-site cardiovascular damage was observed in mice upon respiratory exposure of silica nanoparticles (SiNPs), and the corresponding mechanism was investigated by focusing on the interaction of SiNPs and their encountered biomacromolecules en route. SiNPs were found to collect a significant amount of apolipoprotein A-I (Apo A-I) from the blood, in particular when the SiNPs were preadsorbed with pulmonary surfactants. While the adsorbed Apo A-I ameliorated the cytotoxic and proinflammatory effects of SiNPs, the protein was eliminated from the blood upon clearance of the NPs. However, supplementation of Apo A-I mimic peptide mitigated the atherosclerotic lesion induced by SiNPs. In addition, we found a further declined plasma Apo A-I level in clinical silicosis patients than coronary heart disease patients, suggesting clearance of SiNPs sequestered Apo A-I to compromise the coronal protein's regular biological functions. Together, this study has provided evidence that the protein corona of SiNPs acquired in the blood depletes Apo A-I, a biomarker for prediction of cardiovascular diseases, which gives rise to unexpected toxic effects of the nanoparticles.


Assuntos
Apolipoproteína A-I/deficiência , Doenças Cardiovasculares/etiologia , Nanopartículas/efeitos adversos , Adsorção/efeitos dos fármacos , Animais , Apolipoproteína A-I/sangue , Sistema Cardiovascular , Pulmão , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nanopartículas/química , Nanotecnologia , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Transdução de Sinais/efeitos dos fármacos , Dióxido de Silício/efeitos adversos , Dióxido de Silício/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-38290453

RESUMO

The objective of this study is to assess the efficacy of non-invasive brain stimulation (NIBS) in preventing and treating dysphagia in patients who have experienced a cerebral stroke (CS). Both Chinese and international guidelines for the management of dysphagia resulting from CS mention various non-pharmacological treatments, such as acupuncture, mechanical myoelectric stimulation, and NIBS. However, due to limited evidence, these treatments are often suggested as measures rather than interventions. Therefore, this study assesses the impact of NIBS on the severity and improvement of dysphagia in CS patients. The researchers provide evidence-based recommendations for clinical practice by conducting a comprehensive literature review and meta-analysis. The researchers analyze the impact of NIBS on the severity of dysphagia and its overall improvement in CS patients. Employing a systematic computer-based search, the researchers retrieved randomized controlled trials and cohort studies published between the inception of relevant databases and December 1, 2022, about the utilization of NIBS in managing dysphagia in CS patients. This effort included nine articles for meta-analysis, with sample sizes ranging from 14 to 59, allowing an assessment of the effectiveness of NIBS in CS patients. The analysis revealed a mean difference (MD) score of 1.05 in the NIBS studies for the prevention and treatment of dysphagia severity in stroke patients, indicating a notable alleviation of dysphagia severity in CS patients through NIBS. The MD for the dysphagia score was also 1.05, and the MD for the functional dysphagia score was 1.78, suggesting that NIBS provided relief from dysphagia in CS patients. In summary, this meta-analysis thoroughly evaluated NIBS efficacy in CS patients and provided evidence-based recommendations for clinical practice. Future research needs to collect additional indicators to elucidate the nuances of various interventions, contributing to a more robust theoretical foundation for clinical therapy.

7.
J Formos Med Assoc ; 123(4): 510-516, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307799

RESUMO

PURPOSE: Loneliness is a critical issue affecting the general population. Current evidence from national surveys of loneliness is scarce. The study aimed to examine the impact of COVID-19 pandemic on the prevalence of loneliness and its associating suicide risks in Taiwan. METHODS: Four annual telephone interview surveys were performed by the Taiwan Suicide Prevention Center in 2015-2017 and 2020 during COVID outbreak. Each year the sample was randomly selected by stratifying the general public in different geographical areas and fulfilled a questionnaire collecting information including loneliness, psychological distress, and suicide risk assessment. All the data were analyzed using SPSS25 analysis. RESULTS: A total of 8460 participants were recruited. The average prevalence of loneliness was 12.6 %. Feelings of loneliness was significantly correlated with psychological distress and most risk factors relating to suicide. The odds of loneliness for lifetime suicidal ideation, lifetime suicide attempt, and future suicide intent were 4.9, 5.1, and 9.2, respectively. During the COVID-19 period, loneliness and suicidality demonstrated a noteworthy decline trend, whereas "no one trustworthy to talk to" was the only item that showed significant increase under the pandemic and also impacted on loneliness. CONCLUSION: Nearly one in ten Taiwanese people felt lonely before and during COVID-19. Loneliness was closely linked with various suicide risk factors such as lifetime suicide ideation and attempt or future intention. Although psychological distress and suicide risk were not increased during COVID-19, maintaining trustful relationships to seek support appeared to be critical to prevent the risks of loneliness or suicide.


Assuntos
COVID-19 , População do Leste Asiático , Solidão , Humanos , Solidão/psicologia , Taiwan/epidemiologia , Pandemias , COVID-19/epidemiologia , Ideação Suicida , Fatores de Risco
8.
Nano Lett ; 23(17): 7859-7868, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37433066

RESUMO

Peritoneal metastasis is very common in gastrointestinal, reproductive, and genitourinary tract cancers in late stages or postsurgery, causing poor prognosis, so effective and nontoxic prophylactic strategies against peritoneal metastasis are highly imperative. Herein, we demonstrate the first gene transfection as a nontoxic prophylaxis preventing peritoneal metastasis or operative metastatic dissemination. Lipopolyplexes of TNF-related-apoptosis-inducing-ligand (TRAIL) transfected peritonea and macrophages to express TRAIL for over 15 days. The expressed TRAIL selectively induced tumor cell apoptosis while exempting normal tissue, providing long-term tumor surveillance. Therefore, tumor cells inoculated in the pretransfected peritoneal cavity quickly underwent apoptosis and, thus, barely formed tumor nodules, significantly prolonging the mouse survival time compared with chemotherapy prophylaxis. Furthermore, lipopolyplex transfection showed no sign of toxicity. Therefore, this peritoneal TRAIL-transfection is an effective and safe prophylaxis, preventing peritoneal metastasis.


Assuntos
Proteínas Reguladoras de Apoptose , Neoplasias Peritoneais , Animais , Camundongos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/farmacologia , Ligantes , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/prevenção & controle , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/farmacologia , Apoptose/genética , Fator de Necrose Tumoral alfa/genética , Transfecção , Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética
9.
J Environ Sci (China) ; 138: 32-45, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135399

RESUMO

The air quality in China has improved significantly in the last decade and, correspondingly, the characteristics of PM2.5 have also changed. We studied the interannual variation of PM2.5 in Chengdu, one of the most heavily polluted megacities in southwest China, during the most polluted season (winter). Our results show that the mass concentrations of PM2.5 decreased significantly year-by-year, from 195.8 ± 91.0 µg/m3 in winter 2016 to 96.1 ± 39.3 µg/m3 in winter 2020. The mass concentrations of organic matter (OM), SO42-, NH4+ and NO3- decreased by 49.6%, 57.1%, 49.7% and 28.7%, respectively. The differential reduction in the concentrations of chemical components increased the contributions from secondary organic carbon and NO3- and there was a larger contribution from mobile sources. The contribution of OM and NO3- not only increased with increasing levels of pollution, but also increased year-by-year at the same level of pollution. Four sources of PM2.5 were identified: combustion sources, vehicular emissions, dust and secondary aerosols. Secondary aerosols made the highest contribution and increased year-by-year, from 40.6% in winter 2016 to 46.3% in winter 2020. By contrast, the contribution from combustion sources decreased from 14.4% to 8.7%. Our results show the effectiveness of earlier pollution reduction policies and emphasizes that priority should be given to key pollutants (e.g., OM and NO3-) and sources (secondary aerosols and vehicular emissions) in future policies for the reduction of pollution in Chengdu during the winter months.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Material Particulado/análise , Estações do Ano , Monitoramento Ambiental , China , Aerossóis/análise
10.
Anal Chem ; 95(4): 2129-2133, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36576397

RESUMO

Three-dimensional nondestructive, nanoresolution, and in situ visualization of protein spatial localization in a large, thick single cell remains challenging. In this study, we designed a multifunctional iron oxide (Fe@BFK) nanoprobe that possesses fluorescence and hard X-ray imaging signals. This probe can specifically target the human epidermal growth factor receptor 2 (HER2) protein and help optimize the label condition and selection of suitable samples for X-ray imaging. Combining 30 nm resolution synchrotron radiation hard X-ray nanocomputed tomography and the X-ray-sensitive Fe@BFK nanoprobe, a 3D localization of HER2 on SK-BR-3 cells was obtained for the first time. HER2 was mainly localized and cluster-distributed on the cell membrane with a heterogeneous pattern. This study provides a novel method for the in situ and nondestructive synchrotron radiation imaging of the desired protein localization in large, thick cells and evaluation of the true cellular distribution of a nanoprobe with high resolution.


Assuntos
Tomografia por Raios X , Humanos , Fluorescência
11.
Inorg Chem ; 62(41): 16882-16889, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37796722

RESUMO

Vinylsilanes are valuable building blocks and important structural units in organic chemistry. Herein, catalytic alkyne hydrosilylation was reported to be promoted by a porphyrin metal-organic framework with the incorporation of Pd nanoparticles (Pd@Ir-PCN-222). Catalytic results showed that Pd@Ir-PCN-222 displayed high catalytic efficiency, giving rise to the E isomer vinylsilane with an excellent turnover frequency (TOF) of 2564 h-1. The mechanism studies revealed that the enhancement of the catalytic activity originated from the cooperation between iridium porphyrin and the Pd nanoparticle in confined spaces. The iridium porphyrin was prone to absorb and condense the hydrosilane and alkyne in the inner cavities of Ir-PCN-222, not only accelerating the reaction but also promoting the Pd nanoparticle to activate the Si-H and C≡C bonds of hydrosilane and alkyne, respectively.

12.
Environ Sci Technol ; 57(21): 7891-7901, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37163641

RESUMO

Exposure to atmospheric particulate matter (PM) is a frequent occurrence to humans, and their adverse outcomes have become a global concern. Although PM-induced inflammation is a common phenomenon, a clear picture of the mechanisms underlying exosome-mediated inflammation of PM has not yet emerged. Here, we show that exosomes can mediate the cascade reactions for the transfer of PM and inflammatory responses of macrophages. Specifically, two fine PM2.5, namely F1 (<0.49 µm) and F2 (0.95-1.5 µm), stimulated a substantial release of exosomes from macrophages (THP-1 cells) with the order of F1 > F2, via regulation of the P2X7 receptor (P2X7R). Inhibiting P2X7R with a specific inhibitor largely prevented the secretion of exosomes. In particular, we found that exosomes served as a mediator for the transfer of PM2.5 to the recipient macrophages and activated NF-κB signaling through toll-like receptor 4 (TLR-4), thereby stimulating inflammatory cytokine release and altering the inflammatory phenotype of recipients. Importantly, the exosomes derived from PM2.5-treated macrophages induced the inflammatory responses of lung in mice. Our results highlight that exosomes undergo a secretion-particle transfer-adverse outcome chain in macrophages treated with PM2.5. Given the ubiquitous atmospheric particulate matter, these new findings underscore an urgent need for assessing the secretion of exosomes and their impact on human health via exosome-centric physiological pathways.


Assuntos
Exossomos , Material Particulado , Camundongos , Humanos , Animais , Material Particulado/toxicidade , Exossomos/metabolismo , Citocinas/metabolismo , Macrófagos/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo
13.
Angew Chem Int Ed Engl ; 62(11): e202217448, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36585377

RESUMO

The deficient catalytic activity of nanozymes and insufficient endogenous H2 O2 in the tumor microenvironment (TME) are major obstacles for nanozyme-mediated catalytic tumor therapy. Since electron transfer is the basic essence of catalysis-mediated redox reactions, we explored the contributing factors of enzymatic activity based on positive and negative charges, which are experimentally and theoretically demonstrated to enhance the peroxidase (POD)-like activity of a MoS2 nanozyme. Hence, an acidic tumor microenvironment-responsive and ultrasound-mediated cascade nanocatalyst (BTO/MoS2 @CA) is presented that is made from few-layer MoS2 nanosheets grown on the surface of piezoelectric tetragonal barium titanate (T-BTO) and modified with pH-responsive cinnamaldehyde (CA). The integration of pH-responsive CA-mediated H2 O2 self-supply, ultrasound-mediated charge-enhanced enzymatic activity, and glutathione (GSH) depletion enables out-of-balance redox homeostasis, leading to effective tumor ferroptosis with minimal side effects.


Assuntos
Ferroptose , Neoplasias , Humanos , Molibdênio , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Catálise , Glutationa , Microambiente Tumoral , Peróxido de Hidrogênio
14.
J Am Chem Soc ; 144(21): 9184-9205, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35536591

RESUMO

An inconvenient hurdle in the practice of nanomedicine is the protein corona, a spontaneous collection of biomolecular species by nanoparticles in living systems. The protein corona is dynamic in composition and may entail improved water suspendability and compromised delivery and targeting to the nanoparticles. How much of this nonspecific protein ensemble is determined by the chemistry of the nanoparticle core and its surface functionalization, and how much of this entity is dictated by the biological environments that vary spatiotemporally in vivo? How do we "live with" and exploit the protein corona without significantly sacrificing the efficacy of nanomedicines in diagnosing and curing human diseases? This article discusses the chemical and biophysical signatures of the protein corona and ponders challenges ahead for the field of nanomedicine.


Assuntos
Nanopartículas , Coroa de Proteína , Humanos , Nanomedicina , Nanopartículas/química , Coroa de Proteína/química , Proteínas
15.
Trends Analyt Chem ; 153: 116659, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35527799

RESUMO

Viral infections have been proven a severe threat to human beings, and the pandemic of Coronavirus Disease 2019 (COVID-19) has become a societal health concern, including mental distress and morbidity. Therefore, the early diagnosis and differentiation of viral infections are the prerequisite for curbing the local and global spread of viruses. To this end, carbon nanotubes (CNTs) based virus detection strategies are developed that provide feasible alternatives to conventional diagnostic techniques. Here in this review, an overview of the design and engineering of CNTs-based sensors for virus detection is summarized, followed by the nano-bio interactions used in developing biosensors. Then, we classify the viral sensors into covalently engineered CNTs, non-covalently engineered CNTs, and size-tunable CNTs arrays for viral detection, based on the type of CNTs-based nano-bio interfaces. Finally, the current challenges and prospects of CNTs-based sensors for virus detection are discussed.

16.
Environ Sci Technol ; 56(12): 8319-8325, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35576522

RESUMO

Nanoparticles (NPs) can make their way to the brain and cause in situ damage, which is a concern for nanomaterial application and airborne particulate matter exposure. Our recent study indicated that respiratory exposure to silica nanoparticles (SiO2 NPs) caused unexpected cardiovascular toxic effects. However, the toxicities of SiO2 NPs in other organs have warranted further investigation. To confirm the accumulation of SiO2 NPs in the brain, we introduced SiO2 NPs with different diameters into mice via intranasal instillation (INI) and intravenous injection (IVI) in parallel. We found that SiO2 NPs may target the brain through both olfactory and systemic routes, but the size of SiO2 NPs and delivery routes both significantly affected their brain accumulation. Surprisingly, while equivalent SiO2 NPs were found in the brain regions, brain lesions were distinctly much higher in INI than in the IVI group. Mechanistically, we showed that SiO2 NPs introduced via INI induced brain apoptosis and autophagy, while the SiO2 NPs introduced via IVI only induced autophagy in the brain.


Assuntos
Nanopartículas , Dióxido de Silício , Animais , Apoptose , Encéfalo , Camundongos , Nanopartículas/toxicidade , Material Particulado , Dióxido de Silício/toxicidade
17.
Environ Sci Technol ; 56(17): 12179-12189, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35947795

RESUMO

Uptake kinetics and delivery mechanisms of nanoparticles (NPs) in crop plants need to be urgently understood for the application of nanotechnology in agriculture as delivery systems for eco-friendly nanoagrochemicals. Here, we investigated the uptake kinetics, translocation pathway, and key internalization process of graphene in wheat (Triticum aestivum L.) by applying three specific hydroponic cultivation methods (submerging, hanging, and split-root). Quantification results on the uptake of carbon-14 radiolabeled graphene in each tissue indicated that graphene could enter the root of wheat and further translocate to the shoot with a low delivery rate (<2%). Transmission electron microscopy (TEM) images showed that internalized graphene was transported to adjacent cells through the plasmodesmata, clearly indicating the symplastic pathway of graphene translocation. The key site for the introduction of graphene into root cells for translocation through the symplastic pathway is evidenced to be the apex of growing root hair, where the newly constructed primary cell wall is much thinner. The confirmation of uptake kinetics and delivery mechanisms is useful for the development of nanotechnology in sustainable agriculture, especially for graphene serving as the delivery vector for pesticides, genes, and sensors.


Assuntos
Grafite , Radioisótopos de Carbono/metabolismo , Grafite/metabolismo , Raízes de Plantas/metabolismo , Plântula/metabolismo , Triticum
18.
J Formos Med Assoc ; 121(12): 2416-2423, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36031488

RESUMO

BACKGROUND: The current study aimed to assess the prevalence of bullying victimization (BV) and its association with psychopathology and suicidality in a nationwide general population. METHODS: The target population were all the people living in Taiwan, the study samples were obtained by the following processes. A computer-assisted telephone interview was performed to identify potential respondents using telephone numbers selected with the stratified proportional randomization method. Self-reported data were evaluated. Moreover, data obtained using the validated Brief Symptom Rating Scale (BSRS-5) and Concise Mental Health Checklist (CMHC) were used to evaluate psychopathological symptoms and overall suicidal risks, respectively. Results were further analyzed using the chi-square tests and logistic regression model. RESULTS: In total, 1930 respondents from a national general population survey were included in the analysis. The weighted prevalence of lifetime BV in the general population was 13.5%. Based on the chi-square analysis, individuals exposed to BV were at high risk for psychopathology (a BSRS-5 score of ≥6 (x2 = 45.5, P ≤ .001) and high BSRS-5 scores for all five items). Bullying exposure was significantly associated with lifetime suicide ideation and suicide attempt (x2 = 85.7, P ≤ .001; x2 = 17.0, P ≤ .001, respectively). The help-seeking behavior of respondents exposed to bullying did not differ significantly (x2 = 4.6, P = .327). CONCLUSION: Bullying exposure is associated with recent psychopathology and lifetime suicidality. Multifactorial interactive processes contribute to long-term harmful health implications in adulthood. Nevertheless, further research on the relevant mechanisms associated with bullying and potential interventions that can decrease morbidity must be conducted.


Assuntos
Bullying , Vítimas de Crime , Transtornos Mentais , Suicídio , Humanos , Adulto , Ideação Suicida , Prevalência , Taiwan/epidemiologia , Bullying/psicologia , Vítimas de Crime/psicologia , Transtornos Mentais/epidemiologia , Transtornos Mentais/diagnóstico , Nível de Saúde
19.
Nano Lett ; 21(14): 6005-6013, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34242035

RESUMO

Nanomaterial-biology interaction is the critical step in the fate of biomedical nanomedicines, influencing the consequent biological outcomes. Herein, we present two-dimensional carbon-based nanomaterials-graphdiyne oxide (GDYO) nanosheets that interact with an intracellular protein corona consisting of signal transducer and activator of transcription 3 (STAT3), inducing the reeducation of immunosuppressive macrophages. The interaction at the GDYO-STAT3 interface, driven by structure matching, hydrogen bonding, and salt bridges, simultaneously triggers the immune response in the tumor microenvironment, facilitating cancer immunotherapy. For the first time, our data reveal an interaction mechanism between the nanoparticle-protein interfaces inevitably formed inside the cells that determines the macrophage phenotype. Our results suggest that GDYO nanosheets could be applied for local immunomodulation due to their function and structural organization of the intracellular protein corona occurred inside macrophages.


Assuntos
Coroa de Proteína , Grafite , Imunidade , Imunomodulação , Óxidos
20.
Angew Chem Int Ed Engl ; 61(48): e202204502, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-35972794

RESUMO

Nanocatalytic therapy, involving the nanozyme-triggered production of reactive oxygen species (ROS) in the tumor microenvironment (TME), has demonstrated potential in tumor therapy, but nanozymes still face challenges of activity and specificity that compromise the therapeutic efficacy. Herein, we report a strategy based on a single-atom nanozyme to initiate cascade enzymatic reactions in the TME for tumor-specific treatment. The cobalt-single-atom nanozyme, with Co-N coordination on N-doped porous carbon (Co-SAs@NC), displays catalase-like activity that decomposes cellular endogenous H2 O2 to produce O2 , and subsequent oxidase-like activity that converts O2 into cytotoxic superoxide radicals to efficiently kill tumor cells. By incorporation with doxorubicin, the therapy achieves a significantly enhanced antitumor effect in vivo. Our findings show that cascade TME-specific catalytic therapy combined with chemotherapy is a promising strategy for efficient tumor therapy.


Assuntos
Cobalto , Microambiente Tumoral , Cobalto/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Carbono , Catálise
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