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1.
Nature ; 590(7846): 416-422, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33597761

RESUMO

Crystallization by particle attachment (CPA) is a frequently occurring mechanism of colloidal crystallization that results in hierarchical morphologies1-4. CPA has been exploited to create nanomaterials with unusual properties4-6 and is implicated in the development of complex mineral textures1,7. Oriented attachment7,8-a form of CPA in which particles align along specific crystallographic directions-produces mesocrystals that diffract as single crystals do, although the constituent particles are still discernible2,9. The conventional view of CPA is that nucleation provides a supply of particles that aggregate via Brownian motion biased by attractive interparticle potentials1,9-12. However, mesocrystals often exhibit regular morphologies and uniform sizes. Although many crystal systems form mesocrystals1-9 and individual attachment events have been directly visualized10, how random attachment events lead to well defined, self-similar morphologies remains unknown, as does the role of surface-bound ligands, which are ubiquitous in nanoparticle systems3,9,11. Attempts to understand mesocrystal formation are further complicated in many systems by the presence of precursor nanoparticles with a phase distinct from that of the bulk1,13,14. Some studies propose that such particles convert before attachment15, whereas others attribute conversion to the attachment process itself16 and yet others conclude that transformation occurs after the mesocrystals exceed a characteristic size14,17. Here we investigate mesocrystal formation by iron oxides, which are important colloidal phases in natural environments18,19 and classic examples of systems forming ubiquitous precursor phases and undergoing CPA accompanied by phase transformations15,19-21. Combining in situ transmission electron microscopy (TEM) at 80 degrees Celsius with 'freeze-and-look' TEM, we tracked the formation of haematite (Hm) mesocrystals in the presence of oxalate (Ox), which is abundant in soils, where iron oxides are common. We find that isolated Hm particles rarely appear, but once formed, interfacial gradients at the Ox-covered surfaces drive Hm particles to nucleate repeatedly about two nanometres from the surfaces, to which they then attach, thereby generating mesocrystals. Comparison to natural and synthetic systems suggests that interface-driven pathways are widespread.

2.
Proc Natl Acad Sci U S A ; 119(19): e2106965119, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35522709

RESUMO

Protein scaffolds direct the organization of amorphous precursors that transform into mineralized tissues, but the templating mechanism remains elusive. Motivated by models for the biomineralization of tooth enamel, wherein amyloid-like amelogenin nanoribbons guide the mineralization of apatite filaments, we investigated the impact of nanoribbon structure, sequence, and chemistry on amorphous calcium phosphate (ACP) nucleation. Using full-length human amelogenin and peptide analogs with an amyloid-like domain, films of ß-sheet nanoribbons were self-assembled on graphite and characterized by in situ atomic force microscopy and molecular dynamics simulations. All sequences substantially reduce nucleation barriers for ACP by creating low-energy interfaces, while phosphoserines along the length of the nanoribbons dramatically enhance kinetic factors associated with ion binding. Furthermore, the distribution of negatively charged residues along the nanoribbons presents a potential match to the Ca­Ca distances of the multi-ion complexes that constitute ACP. These findings show that amyloid-like amelogenin nanoribbons provide potent scaffolds for ACP mineralization by presenting energetically and stereochemically favorable templates of calcium phosphate ion binding and suggest enhanced surface wetting toward calcium phosphates in general.


Assuntos
Proteínas do Esmalte Dentário , Nanotubos de Carbono , Amelogenina/química , Proteínas Amiloidogênicas , Sítios de Ligação , Fosfatos de Cálcio
3.
Nano Lett ; 24(4): 1153-1159, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38232325

RESUMO

Twin structures possess distinct physical and chemical properties by virtue of their specific twin configuration. However, twinning and detwinning processes are not fully understood on the atomic scale. Integrating in situ high resolution transmission electron microscopy and molecular dynamic simulations, we find tensile strain in the asymmetrical 5-fold twins of Au nanoparticles leads to twin boundary migration through dislocation sliding (slipping of an atomic layer) along twin boundaries and dislocation reactions at the 5-fold axis under an electron beam. Migration of one or two layers of twin planes is governed by energy barriers, but overall, the total energy, including surface, lattice strain, and twin boundary energy, is relaxed after consecutive twin boundary migration, leading to a detwinning process. In addition, surface rearrangement of 5-fold twinned nanoparticles can aid in the detwinning process.

4.
Nano Lett ; 24(33): 10244-10250, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39116288

RESUMO

The effectiveness of the room-temperature strengthening strategy for aluminum (Al) is compromised at increased temperatures due to grain and precipitate phase coarsening. Overcoming the heightened activity of grain boundaries and dislocations poses a significant challenge in enhancing the high-temperature strength through traditional precipitation strengthening. This study presents novel strengthening strategies that integrate intergranular reinforcements, intragranular reinforcements, refined grain, and stacking faults within an (Al2O3+Al3Ti)/Al composite prepared using sol-gel and powder metallurgy technology. Excellent high-temperature tensile properties are achieved; also, a remarkable fatigue performance at increased temperatures that surpasses those of other existing Al alloys and composites is revealed. These superior characteristics can be attributed to its exceptionally stable microstructure and the synergistic strengthening mechanisms mentioned above. This work offers new insights into designing and fabricating thermally stable Al matrix composites for high-temperature applications.

5.
Int J Cancer ; 154(11): 1877-1889, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429857

RESUMO

In recent years, breast cancer (BC) has surpassed lung cancer as the most common malignant tumor worldwide and remains the leading cause of cancer death in women. The etiology of BC usually involves dysregulation of epigenetic mechanisms and aberrant expression of certain non-coding RNAs (ncRNAs). N6-methyladenosine (m6A), the most prevalent RNA modification in eukaryotes, widely exists in ncRNAs to affect its biosynthesis and function, and is an important regulator of tumor-related signaling pathways. Interestingly, ncRNAs can also regulate or target m6A modification, playing a key role in cancer progression. However, the m6A-ncRNAs regulatory network in BC has not been fully elucidated, especially the regulation of m6A modification by ncRNAs. Therefore, in this review, we comprehensively summarize the interaction mechanisms and biological significance of m6A modifications and ncRNAs in BC. Meanwhile, we also focused on the clinical application value of m6A modification in BC diagnosis and prognosis, intending to explore new biomarkers and potential therapeutic targets.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Feminino , Humanos , Neoplasias da Mama/genética , Adenosina/genética , Epigênese Genética , RNA não Traduzido/genética
6.
Small ; 20(26): e2310423, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38263809

RESUMO

Infrared nonlinear optical (IR NLO) materials play significant roles in laser technology. The novel functional building units (FBUs) are of great importance in constructing NLO materials with strong second harmonic generation (SHG). Herein, polysulfide anion [Sx]2- (x = 2, 3, 4, 5) units are investigated on NLO-related properties and structure-performance relationships. Theoretical calculations uncover that the [Sx]2- (x = 2, 3, 4, 5) units are potential IR NLO FBUs with large polarizability anisotropy (δ), hyperpolarizability (ß) and wide HOMO-LUMO gap. Fourteen crystals including [Sx]2- (x = 2, 3, 4, 5) units are calculated and analyzed. The results show that these units can result in a wide IR transmittance range, significant SHG effects, wide band gap Eg (Na2S4: Eg = 3.09 eV), and large birefringence Δn [BaS3 (P21212): Δn = 0.70]. More importantly, it is highlighted that the crystal materials including with [Sx]2- (x = 2, 3, 4, 5) groups are good candidates for the exploration of the outstanding IR NLO materials.

7.
Psychol Res ; 88(7): 2080-2095, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39088012

RESUMO

Cognitive control has been investigated in attentional conflict tasks for a long time. One representative phenomenon of adaptive cognitive control in these tasks is the congruency sequence effect (CSE), which means that a previous conflict will lead to reduced congruency effects at the current moment, reflecting increased control of attention toward the task at hand. One debating question is whether CSE can generalize between different conditions. Since a similar phenomenon (i.e., validity sequence effect, VSE) has been found in spatial cueing tasks, this study investigated whether the two sequential effects could generalize between each other. A cross-task sequence effect is found from previous flanker trials to current cueing trials when the task sets of the two tasks are either very similar or sufficiently dissimilar, and this C-VSE effect is influenced by the response mode of the experimental design. In addition, the VSE between trial n-2 and trial n is eliminated by the existence of an intermediate flanker trial, but the CSE between trial n-2 and trial n is still significant even with an intermediate cueing trial. Possible explanations of these findings are discussed. The findings suggest a close connection between orienting and executive control processes in attention networks and provide a new perspective and method for investigating the potential mechanisms of cognitive control.


Assuntos
Atenção , Conflito Psicológico , Sinais (Psicologia) , Função Executiva , Humanos , Masculino , Atenção/fisiologia , Feminino , Adulto , Adulto Jovem , Função Executiva/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Generalização Psicológica/fisiologia
8.
Altern Ther Health Med ; 30(11): 331-339, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39110050

RESUMO

Objective: Multiple system atrophy (MSA) is a rare and fatal adult-onset neurodegenerative disease with multiple clinical and pathological variants. The etiology of MSA remains uncertain. Orthostatic hypotension (OH) is the main characteristic of MSA. An upright position can trigger a syncope attack, making it impossible for the patient to stand and walk briefly. Case Study: We report the case of a 67-year-old man with initial symptoms of recurrent syncope and this patient was hospitalized several times, despite multiple therapeutic interventions, his symptoms persisted. Eventually, this patient died at the age of 68 with a diagnosis of MSA. Conclusion: For those patients with neurogenic OH, an underlying neurodegenerative disease should always be considered. Prompt diagnosis, early aggressive treatment, and prediction of complications may have a huge impact on the prognosis of MSA. This article also reviews relevant reported cases to enrich the experience of treating MSA in the clinic.


Assuntos
Hipotensão Ortostática , Atrofia de Múltiplos Sistemas , Humanos , Atrofia de Múltiplos Sistemas/complicações , Atrofia de Múltiplos Sistemas/fisiopatologia , Hipotensão Ortostática/etiologia , Hipotensão Ortostática/complicações , Idoso , Masculino , Evolução Fatal , Síncope/etiologia
9.
Ecotoxicol Environ Saf ; 283: 116834, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39106569

RESUMO

Radiotherapy is a common treatment for abdominal and pelvic tumors, while the radiation-induced intestinal injury (RIII) is one of the major side-effects of radiotherapy, which reduces the life quality and impedes the treatment completion of cancer patients. Previous studies have demonstrated that environmental pollutant microplastics led to various kinds of injury in the gut, but its effects on RIII are still uncovered. In this study, we fed the C57BL/6J mice with distilled water or 50 µg/d polystyrene microplastics (PSMPs) for 17 days and exposed the mice to total abdominal irradiation (TAI) at day 14. Then the severity of RIII was examined by performing histopathological analysis and microbial community analysis. The results demonstrated that PSMPs significantly aggravated RIII in small intestine rather than colon of mice upon TAI. PSMPs increased levels of the histopathological damage and the microbial community disturbance in mice small intestine, shown by the overabundance of Akkermansiaceae and the decrease of microflora including Lactobacillaceae, Muribaculaceae and Bifidobacteriaceae. In conclusion, our results suggested that more microplastics exposure might led to more severe RIII, which should be considered in patients' daily diet adjustment and clinical radiotherapy plan evaluation. Furthermore, this study also called for the further researches to uncover the underlying mechanism and develop novel strategies to attenuate RIII in mice intestine.


Assuntos
Camundongos Endogâmicos C57BL , Microplásticos , Poliestirenos , Animais , Microplásticos/toxicidade , Camundongos , Poliestirenos/toxicidade , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos da radiação , Intestinos/efeitos da radiação , Intestinos/efeitos dos fármacos , Intestinos/patologia , Intestino Delgado/efeitos da radiação , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/patologia , Lesões por Radiação/patologia
10.
J Am Chem Soc ; 145(48): 26016-26027, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37976467

RESUMO

Proton transfer is critically important to many electrocatalytic reactions, and directed proton delivery could open new avenues for the design of electrocatalysts. However, although this approach has been successful in molecular electrocatalysis, proton transfer has not received the same attention in heterogeneous electrocatalyst design. Here, we report that a metal oxide proton relay can be built within heterogeneous electrocatalyst architectures and improves the kinetics of electrochemical hydrogen evolution and oxidation reactions. The volcano-type relationship between activity enhancement and pKa of amine additives confirms this improvement; we observe maximum rate enhancement when the pKa of a proton relay matches the pH of the electrolyte solution. Density-functional-theory-based reactivity studies reveal a decreased proton transfer energy barrier with a metal oxide proton relay. These findings demonstrate the possibility of controlling the proton delivery and enhancing the reaction kinetics by tuning the chemical properties and structures at heterogeneous interfaces.

11.
Breast Cancer Res ; 25(1): 126, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858183

RESUMO

Breast cancer metastasis is a complex, multi-step process, with high cellular heterogeneity between primary and metastatic breast cancer, and more complex interactions between metastatic cancer cells and other cells in the tumor microenvironment. High-resolution single-cell transcriptome sequencing technology can visualize the heterogeneity of malignant and non-malignant cells in the tumor microenvironment in real time, especially combined with spatial transcriptome analysis, which can directly compare changes between different stages of metastatic samples. Therefore, this study takes single-cell analysis as the first perspective to deeply explore special or rare cell subpopulations related to breast cancer metastasis, systematically summarizes their functions, molecular features, and corresponding treatment strategies, which will contribute to accurately identify, understand, and target tumor metastasis-related driving events, provide a research basis for the mechanistic study of breast cancer metastasis, and provide new clues for its personalized precision treatment.


Assuntos
Neoplasias da Mama , Melanoma , Humanos , Feminino , Neoplasias da Mama/patologia , Transcriptoma , Perfilação da Expressão Gênica , Microambiente Tumoral/genética , Análise de Célula Única , Melanoma Maligno Cutâneo
12.
Ecotoxicol Environ Saf ; 256: 114846, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37018856

RESUMO

Aflatoxin B1 (AFB1) is an extremely hazardous and unavoidable pollutant for cereals and feedstuff. AFB1 can cause testicular lesion, and how to alleviate its testicular toxicity has received much attention in recent years. Lycopene (LYC), a foodborne nutrient derived from red fruits and vegetables, has protective effects against sperm abnormality and testicular lesions. To confirm the beneficial effects and mechanisms of LYC on AFB1-induced testicular lesion, 48 male mice were exposed to 0.75 mg/kg AFB1 or/and 5 mg/kg LYC for consecutive 30 days. Results demonstrated the LYC significantly restored the lesions of testicular microstructure and ultrastructure, and sperm abnormalities in AFB1-exposed mice. Furthermore, LYC effectively attenuated AFB1-induced oxidative stress and mitochondrial damage, including ameliorative mitochondrial structural, and elevated mitochondrial biogenesis for maintaining mitochondrial function. Meanwhile, LYC resisted AFB1-induced mitochondrial-dependent apoptosis. In addition, LYC promoted nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation, and upregulated the Nrf2 signaling pathway. Collectively, our findings demonstrate LYC ameliorates AFB1-induced testicular lesion by attenuating oxidative stress and mitochondrial damage, which is related to the activation of Nrf2.


Assuntos
Aflatoxina B1 , Fator 2 Relacionado a NF-E2 , Masculino , Animais , Camundongos , Licopeno/metabolismo , Licopeno/farmacologia , Aflatoxina B1/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Sementes/metabolismo , Estresse Oxidativo
13.
Ecotoxicol Environ Saf ; 264: 115459, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37703808

RESUMO

Aluminum is a neurotoxic food contaminant. Aluminum trichloride (AlCl3) causes hippocampal mitochondrial damage, leading to hippocampal injury. Damaged mitochondria can release mitochondrial reactive oxygen species (mtROS) and activate nucleotide-binding oligomerization domain-like receptor-containing 3 (NLRP3) inflammasomes and apoptosis. E3 ubiquitin ligase PARK2 (Parkin)-mediated mitophagy can attenuate mitochondrial damage. However, the role of mitophagy in AlCl3-induced mice hippocampal damage and its regulatory mechanism remain elusive. First, C57BL/6 N mice were treated with 0, 44.825, 89.65, and 179.3 mg/kg body weight AlCl3 drinking water for 90 d. Apoptosis, NLRP3-inflammasome activation and mitochondrial damage were increased in AlCl3-induced hippocampal damage. In addition, Parkin-mediated mitophagy peaked in the middle-dose group and was slightly attenuated in the high-dose group. Subsequently, we used wild-type and Parkin knockout (Parkin-/-) mice to investigate the AlCl3-induced hippocampal damage. The results showed that Parkin-/- inhibited mitophagy, and aggravated AlCl3-induced mitochondrial damage, NLRP3-inflammasome activation, apoptosis and hippocampal damage. Finally, we administered MitoQ (mtROS inhibitor) and MCC950 (NLRP3 inhibitor) to AlCl3-treated Parkin-/- mice to investigate the mechanism of Parkin-mediated mitophagy. The results showed that inhibition of mtROS and NLRP3 attenuated hippocampal NLRP3-inflammasome activation, apoptosis, and damage in AlCl3-treated Parkin-/- mice. These findings indicate that Parkin-mediated mitophagy protects against AlCl3-induced hippocampal apoptosis in mice via the mtROS-NLRP3 pathway.


Assuntos
Cloreto de Alumínio , Hipocampo , Inflamassomos , Mitofagia , Animais , Camundongos , Cloreto de Alumínio/toxicidade , Apoptose , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética
14.
Int J Mol Sci ; 24(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139168

RESUMO

Plasma membrane H+-ATPases (PMAs) play an important role in the pathogenicity of pathogenic fungi. Lipid droplets are important storage sites for neutral lipids in fungal conidia and hyphae and can be used by plant pathogenic fungi for infection. However, the relationship between plasma membrane H+-ATPase, lipid droplets and virulence remains unclear. Here, we characterized a plasma membrane H+-ATPase, CsPMA2, that plays a key role in lipid droplet formation, appresorial development and virulence in C. siamense. Deletion of CsPMA2 impaired C. siamense conidial size, conidial germination, appressorial development and virulence but did not affect hyphal growth. ΔCsPMA2 increased the sensitivity of C. siamense to phytic acid and oxalic acid. CsPMA2 was localized to lipids on the plasma membrane and intracellular membrane. Deletion of CsPMA2 significantly inhibited the accumulation of lipid droplets and significantly affected the contents of some species of lipids, including 12 species with decreased lipid contents and 3 species with increased lipid contents. Furthermore, low pH can inhibit CsPMA2 expression and lipid droplet accumulation. Overall, our data revealed that the plasma membrane H+-ATPase CsPMA2 is involved in the regulation of lipid droplet formation and affects appressorial development and virulence in C. siamense.


Assuntos
Colletotrichum , Gotículas Lipídicas , Virulência , Gotículas Lipídicas/metabolismo , Proteínas Fúngicas/metabolismo , Lipídeos , Membrana Celular/metabolismo , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo
15.
Am J Physiol Gastrointest Liver Physiol ; 322(2): G256-G267, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34935515

RESUMO

The molecular mechanism underlying hyperuricemia-induced lipid metabolism disorders is not clear. The purpose of the current study was to investigate the mechanism of lipid disturbances in a hyperuricemia mice model. RNA-Seq showed that differentially expressed genes (DEGs) in the fatty acid synthesis signaling pathway were mainly enriched and CXCL-13 was significantly enriched in protein-protein interaction networks. Western blotting, Q-PCR, and immunofluorescence results further showed that hyperuricemia upregulated CXCL-13 and disturbed lipid metabolism in vivo and in vitro. Furthermore, CXCL-13 alone also promoted the accumulation of lipid droplets and upregulated the expression of FAS and SREBP1, blocking AMPK signaling and activating the PKC and P38 signaling pathways. Silencing CXCL-13 reversed uric-acid-induced lipid droplet accumulation, which further downregulated FAS and SREBP1 expression, inhibited the p38 and PKC signaling, and activated AMPK signaling. In conclusion, hyperuricemia induces lipid metabolism disorders via the CXCL-13 pathway, making CXCL-13 a key regulatory factor linking hyperuricemia and lipid metabolism disorders. These results may provide novel insights for the treatment of hyperuricemia.NEW & NOTEWORTHY The underlying molecular mechanism of hyperuricemia-induced lipid metabolism disorders is still unclear. The study aimed to investigate the mechanism of lipid disturbance in hyperuricemia mice model. To our knowledge, we proposed for the first time that CXCL-13 may be a key regulator of hyperuricemia and lipid metabolism disorders. These results may provide new insights for the clinical treatment of hyperuricemia.


Assuntos
Quimiocina CXCL13/metabolismo , Hiperuricemia/metabolismo , Metabolismo dos Lipídeos/fisiologia , Transdução de Sinais/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Células Hep G2/metabolismo , Humanos , Fígado/metabolismo , Camundongos , Regulação para Cima
16.
Fungal Genet Biol ; 158: 103649, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34921997

RESUMO

In phytopathogenic fungi, the HOG MAPK pathway has roles in osmoregulation, fungicide sensitivity, and other processes. The ATF1/CREB-activating transcription factor Atf1 is a regulator that functions downstream of the HOG MAPK pathway. Here, we identified a gene, designated CsAtf1, that encodes a bZIP transcription factor in Colletotrichum siamense, which is the main pathogen that causes Colletotrichum leaf fall disease in rubber trees in China. CsAtf1 localizes to the nucleus. Its mRNA expression correlates positively with that of CsPbs2 and CsHog1 in the HOG MAPK pathway in response to activator (anisomycin), inhibitor (SB203580) and fludioxonil treatments. The CsAtf1 deletion mutant showed slightly retarded mycelial growth, small conidia, slow spore germination, and abnormal appressorium formation. This mutant showed the increased spore germination rate after fludioxonil treatment and more resistance to the fungicide fludioxonil than did the wild-type fungus. However, unlike deletion of Pbs2 or Hog1, which resulted in greater sensitivity to osmotic stress, the CsAtf1 deletion induced slightly increased resistance to osmotic stress and the cell wall stress response. The ΔCsAtf1 strain also exhibited significantly reduced virulence on rubber tree leaves. These data revealed that CsAtf1 plays a key role in the regulation of fludioxonil sensitivity and in pathogenicity regulation in C. siamense.


Assuntos
Colletotrichum , Hevea , Fatores de Transcrição de Zíper de Leucina Básica , Colletotrichum/genética , Dioxóis , Proteínas Fúngicas/genética , Doenças das Plantas , Pirróis , Virulência/genética
17.
Psychol Res ; 86(6): 1944-1957, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34709462

RESUMO

Sequential modulations have been found in both conflict and spatial orienting tasks. The former is called congruency sequence effects (CSE) and the latter is called validity sequence effects (VSE). Although the two effects have similar phenomenon descriptions, the relationship of the cognitive control mechanisms under the two effects is still unclear. Using a modified attentional network test (ANT), a flanker task and an arrow cueing task are integrated into a single task, which enables the test of the possible interactions between CSE and VSE. Since a confound-minimized design is used, the observed sequence effects cannot be attributed to the feature integration of low-level stimulus features or the contingency learning. It was found that the CSE are only significant when the arrow cue in preceding trial is invalid, and the VSE are only significant when the target letter in preceding trial is congruent with the distractor letters. The findings suggest that the sequential modulations during orienting and executive control of attention networks are highly interacted with each other, and the sequence effects in these networks are possibly controlled by a complex and multifaceted adaptive control mechanism.


Assuntos
Sinais (Psicologia) , Função Executiva , Condicionamento Clássico , Humanos , Tempo de Reação
18.
Environ Toxicol ; 37(10): 2341-2353, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35716031

RESUMO

Dibutyl phthalate (DBP) is a plasticizer widely used in daily production, which causes serious environmental pollution, and damage to brain, liver, kidney, and lung by producing excessive reactive oxygen species (ROS) after entering the body. DBP can also cause skeletal dysplasia, but it is unclear whether ROS is involved. In addition, overproduction of ROS can activate mitophagy, which is an important mechanism for regulating mitochondrial quality and cell homeostasis. In order to investigate whether DBP can damage MC3T3-E1 cells (osteoblast cell line) and whether ROS and mitophagy are involved, DBP toxicity experiment, Parkin gene silencing experiment, and N-acetylcysteine (NAC) intervention experiment were performed on MC3T3-E1 cells in turn. First, we found that DBP caused MC3T3-E1 cell viability decline and osteogenic dysfunction, accompanied by the overproduction of ROS and the activation of mitophagy. Then, we found that silencing Parkin expression alleviated DBP-induced apoptosis and osteogenic dysfunction of MC3T3-E1 cells. In addition, NAC treatment inhibited the PINK1/Parkin-mediated mitophagy and alleviated the apoptosis and osteogenic dysfunction of MC3T3-E1 cells caused by DBP. Our research results showed that DBP could cause MC3T3-E1 cell damage by increasing ROS to promote the PINK1/Parkin-mediated mitophagy.


Assuntos
Dibutilftalato , Mitofagia , Acetilcisteína/farmacologia , Dibutilftalato/toxicidade , Mitofagia/genética , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
19.
Environ Toxicol ; 37(7): 1653-1661, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35289972

RESUMO

T-2 toxin is one of the most common mycotoxins found in grain foods, animal feed, and other agricultural by-products causing food contamination and health threat. The skeletal system is the main target tissue for T-2 toxin. T-2 toxin exposure is also recognized as a potential contributor to multiple types of bone diseases, including Kashin-Beck disease. However, the mechanisms of T-2 toxin-induced bone toxicity remain unclear. In this study, 60 male C57BL/6 mice were exposed T-2 toxin with 0, 0.5, 1 or 2 mg/kg body weight by intragastric administration for 28 days, respectively. Femora were collected for the detections of femur lesion, bone formation factors, oxidative stress, autophagy, apoptosis, and Wnt/ß-catenin signaling. Our research showed that T-2 toxin caused bone formation disorders, presenting as the reduction of the BMD and femur length, bone structure changes and abnormal bone formation proteins expressions, along with enhanced oxidative stress. Meanwhile, T-2 toxin increased expressions of autophagy-related proteins (Beclin 1, ATG5, p62, and LC3), and promoted apoptosis in mouse femur. Moreover, T-2 toxin suppressed the Wnt/ß-catenin signaling and expressions of downstream target genes. Taken together, our data indicated T-2 toxin-induced femur lesion was accompanied by autophagy and apoptosis, which was associated with Wnt/ß-catenin signaling.


Assuntos
Fêmur , Toxina T-2 , Via de Sinalização Wnt , Animais , Apoptose , Autofagia , Fêmur/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Toxina T-2/toxicidade , beta Catenina/metabolismo
20.
BMC Plant Biol ; 21(1): 82, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33557748

RESUMO

BACKGROUND: Fusarium crown rot is major disease in wheat. However, the wheat defense mechanisms against this disease remain poorly understood. RESULTS: Using tandem mass tag (TMT) quantitative proteomics, we evaluated a disease-susceptible (UC1110) and a disease-tolerant (PI610750) wheat cultivar inoculated with Fusarium pseudograminearum WZ-8A. The morphological and physiological results showed that the average root diameter and malondialdehyde content in the roots of PI610750 decreased 3 days post-inoculation (dpi), while the average number of root tips increased. Root vigor was significantly increased in both cultivars, indicating that the morphological, physiological, and biochemical responses of the roots to disease differed between the two cultivars. TMT analysis showed that 366 differentially expressed proteins (DEPs) were identified by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment in the two comparison groups, UC1110_3dpi/UC1110_0dpi (163) and PI610750_3dpi/PI610750_0dpi (203). It may be concluded that phenylpropanoid biosynthesis (8), secondary metabolite biosynthesis (12), linolenic acid metabolites (5), glutathione metabolism (8), plant hormone signal transduction (3), MAPK signaling pathway-plant (4), and photosynthesis (12) contributed to the defense mechanisms in wheat. Protein-protein interaction network analysis showed that the DEPs interacted in both sugar metabolism and photosynthesis pathways. Sixteen genes were validated by real-time quantitative polymerase chain reaction and were found to be consistent with the proteomics data. CONCLUSION: The results provided insight into the molecular mechanisms of the interaction between wheat and F. pseudograminearum.


Assuntos
Resistência à Doença/genética , Fusarium/patogenicidade , Variação Genética , Genótipo , Doenças das Plantas/genética , Triticum/crescimento & desenvolvimento , Triticum/genética , Grão Comestível/genética , Grão Comestível/microbiologia , Proteômica , Triticum/microbiologia
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