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1.
Langmuir ; 40(37): 19506-19516, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39205649

RESUMO

The efficacy and structural evolution of Mo-doped titania nanoparticles (MTNPs) as advanced photocatalysts for degrading methyl blue (MB) are investigated by X-ray absorption spectroscopy (XAS). The 3 wt % MTNP, characterized by uniform size and anatase structure, exhibits higher efficiency. The spectral analyses unveiled structural variations in the TiO6 octahedral structure and revealed an active site of the distorted square pyramidal structure symmetry (C4v). The in situ XAS spectra illustrate that MTNPs, particularly at 3 wt % doping, effectively enhanced the hole carriers in Ti 3d orbitals with a charge transfer to Mo 4d orbitals and impeded electron-hole pair merging, significantly enhancing the photodegradation under light illumination. This study deepens our understanding of the crucial role of Mo doping in optimizing TiO2 nanoparticle performance for efficient environmental remediation, showcasing the potential of MTNPs as sustainable photocatalytic materials.

2.
J Ovarian Res ; 17(1): 66, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504307

RESUMO

BACKGROUND: Quiescin sulfhydryl oxidase 2 (QSOX2) is a flavin adenine dinucleotide-dependent sulfhydryl oxidase that is known to be involved in protein folding, cell growth regulation, and redox state modification through oxidative activities. Earlier studies demonstrated the tissue and cellular localization of QSOX2 in the male reproductive tract, as well as the highly-regulated mechanism of QSOX2 protein synthesis and expression through the coordinated action of testosterone and epididymal-enriched amino acid, glutamate. However, the presence and the functions of QSOX2 in female reproduction are unknown. In this study, we applied the Cre-loxP gene manipulation system to generate the heterozygous and homozygous Qsox2 knockout mice and examined its effects on ovarian function. RESULTS: We demonstrated that QSOX2 was detected in the follicle-supporting cells (granulosa and cumulus cells) of ovarian follicles of all stages but was absent in the corpus luteum, suggesting its supportive role in folliculogenesis. In comparison with reproductive organogenesis in wild-type mice, there was no difference in testicular and epididymal structure in male Qsox2 knockout; however, Qsox2 knockout disrupted the regular ovulation process in female mice as a drastic decrease in the formation of the corpus luteum was detected, and no pregnancy was achieved when mating males with homozygous Qsox2 knockout females. RNAseq analyses further revealed that Qsox2 knockout altered critical signaling pathways and genes that are responsible for maintaining ovarian functions. CONCLUSION: Our data demonstrated for the first time that Qsox2 is critical for ovarian function in mice.


Assuntos
Células da Granulosa , Oxirredutases , Tamoxifeno , Feminino , Camundongos , Masculino , Animais , Células da Granulosa/metabolismo , Tamoxifeno/farmacologia , Tamoxifeno/metabolismo , Ovário , Ovulação , Camundongos Knockout
3.
Neuroscience ; 542: 33-46, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38354901

RESUMO

The forkhead box protein P2 (Foxp2), initially identified for its role in speech and language development, plays an important role in neural development. Previous studies investigated the function of the Foxp2 gene by deleting or mutating Foxp2 from developmental stages. Little is known about its physiological function in adult brains. Although Foxp2 has been well studied in the dorsal striatum, its function in the nucleus accumbens (NAc) of the ventral striatum remains elusive. Here, we examine the physiological function of Foxp2 in NAc of mouse brains. We conditionally knocked out Foxp2 by microinjections of AAV-EGFP-Cre viruses into the medial shell of NAc of Foxp2 floxed (cKO) mice. Immunostaining showed increased c-Fos positive cells in cKO NAc at basal levels, suggesting an abnormality in Foxp2-deficient NAc cells. Unbiased behavioral profiling of Foxp2 cKO mice showed abnormalities in limbic-associated function. Foxp2 cKO mice exhibited abnormal social novelty without preference for interaction with strangers and familiar mice. In appetitive reward learning, Foxp2 cKO mice failed to learn the time expectancy of food delivery. In fear learning, Foxp2 cKO mice exhibited abnormal increases in freezing levels in response to tone paired with foot shock during fear conditioning. The extinction of the fear response was also altered in Foxp2 cKO mice. In contrast, conditional knockout of Foxp2 in NAc did not affect locomotion, motor coordination, thermal pain sensation, anxiety- and depression-like behaviors. Collectively, our study suggests that Foxp2 has a multifaceted physiological role in NAc in the regulation of limbic function in the adult brain.


Assuntos
Aprendizagem , Núcleo Accumbens , Camundongos , Animais , Núcleo Accumbens/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Proteínas Repressoras/metabolismo
4.
BMC Palliat Care ; 22(1): 201, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097993

RESUMO

BACKGROUND: Hemodialysis holds the highest incidence and prevalence rate in Taiwan globally. However, the implementation of advance care planning (ACP), advance directives (AD), and patient self-determination acts (PSDA) remains limited. Our objective was to examine the current status of ACP, AD and PSDA and potential opportunities for enhancement. METHODS: We developed a novel questionnaire to assess individuals' knowledge, attitudes, and intentions regarding ACP, AD, and PSDA. We also collected baseline characteristics and additional inquiries for correlation analysis to identify potential factors. Student's t-test and Analysis of Variance were employed to assess significance. RESULTS: Initially, a cohort of 241 patients was initially considered for inclusion in this study. Subsequently, 135 patients agreed to participate in the questionnaire study, resulting in 129 valid questionnaires. Among these respondents, 76 were male (59.9%), and 53 were female (41.1%). Only 13.2% had signed AD. A significant portion (85.3%) indicated that they had not discussed their dialysis prognosis with healthcare providers. Additionally, a mere 14% engaged in conversations about life-threatening decisions. Ninety percent believed that healthcare providers had not furnished information about ACP, and only 30% had discussed such choices with their families. The findings revealed that the average standardized score for ACP and AD goals was 84.97, while the attitude towards PSDA received a standardized score of 69.94. The intention score stood at 69.52 in standardized terms. Potential candidates for ACP initiation included individuals aged 50 to 64, possessing at least a college education, being unmarried, and having no history of diabetes. CONCLUSION: Patients undergoing hemodialysis exhibited a significant knowledge gap concerning ACP, AD, and the PSDA. Notably, a substantial number of dialytic patients had not received adequate information on these subjects. Nevertheless, they displayed a positive attitude, and a considerable proportion expressed a willingness to sign AD. It is imperative for nephrologists to take an active role in initiating ACP discussions with patients from the very beginning.


Assuntos
Planejamento Antecipado de Cuidados , Patient Self-Determination Act , Estados Unidos , Humanos , Masculino , Feminino , Intenção , Conhecimentos, Atitudes e Prática em Saúde , Diretivas Antecipadas , Diálise Renal
5.
Molecules ; 28(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37959865

RESUMO

Lung cancer has a high incidence rate worldwide, necessitating the development of new drugs. Although Magnolia figo (Lour.) DC. is known for its medicinal properties, studies on its efficacy against lung cancer are lacking. This study investigated whether the supercritical fluid extract of M. figo (FMO) can induce apoptosis in A549, a human non-small-cell lung cancer cell line. The cell viability was assessed using an MTT assay. A terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analysis and flow cytometry analysis were conducted. The expression of factors was assessed through Western blotting analyses. Gas chromatography-mass spectrometry (GC-MS) was performed. The results revealed that FMO treatment exhibited cytotoxicity, demonstrating dose-dependent effects. The TUNEL analysis and flow cytometry analysis revealed that FMO induced apoptosis in A549 cells. The Western blotting analysis revealed that FMO upregulated the expression of p53 and Bax protein, and downregulated the expression of Bcl-2 protein. The GC-MS analysis revealed eight components identified in FMO. These findings indicate that FMO can induce A549 apoptosis through the p53/Bcl-2/Bax pathways, confirming the apoptotic effects of M. figo on lung cancer cells. These results highlight the potential, for the first time, of M. figo as a source for developing novel drugs for lung cancer treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Magnolia , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Magnolia/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proliferação de Células
6.
Development ; 150(16)2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37497597

RESUMO

Morphological development of the lung requires complex signal crosstalk between the mesenchymal and epithelial progenitors. Elucidating the genetic cascades underlying signal crosstalk is essential to understanding lung morphogenesis. Here, we identified Nolz1 as a mesenchymal lineage-specific transcriptional regulator that plays a key role in lung morphogenesis. Nolz1 null mutation resulted in a severe hypoplasia phenotype, including a decreased proliferation of mesenchymal cells, aberrant differentiation of epithelial cells and defective growth of epithelial branches. Nolz1 deletion also downregulated Wnt2, Lef1, Fgf10, Gli3 and Bmp4 mRNAs. Mechanistically, Nolz1 regulates lung morphogenesis primarily through Wnt2 signaling. Loss-of-function and overexpression studies demonstrated that Nolz1 transcriptionally activated Wnt2 and downstream ß-catenin signaling to control mesenchymal cell proliferation and epithelial branching. Exogenous Wnt2 could rescue defective proliferation and epithelial branching in Nolz1 knockout lungs. Finally, we identified Fgf9 as an upstream regulator of Nolz1. Collectively, Fgf9-Nolz1-Wnt2 signaling represents a novel axis in the control of lung morphogenesis. These findings are relevant to lung tumorigenesis, in which a pathological function of Nolz1 is implicated.


Assuntos
Pulmão , Transdução de Sinais , Transdução de Sinais/fisiologia , Diferenciação Celular/genética , Células Epiteliais , Morfogênese/genética , Mesoderma , Regulação da Expressão Gênica no Desenvolvimento
7.
J Org Chem ; 88(13): 8441-8453, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37276376

RESUMO

Herein, we present a facile synthetic methodology to produce a range of N-(CH2-aryl/alkyl)-substituted N-(pyridin-2-yl)benzamides via palladium-mediated C(sp3)-H bond activation. The N-methyl-N-(pyridin-2-yl)benzamide precursor was first reacted with palladium(II) acetate in a stoichiometric manner to obtain the key dinuclear palladacycle intermediates, whose structures were elucidated by mass spectrometric, NMR spectroscopic, and X-ray crystallographic studies in detail. The subsequent C(sp3)-H bond functionalizations on the N-methyl group of the starting substrate show facile productions of the corresponding N-(CH2-aryl/alkyl)-substituted N-(pyridin-2-yl)benzamides with good functional group tolerance. A plausible mechanism was proposed based on density functional theory calculations in conjunction with kinetic isotope effect experiments. Finally, the synthetic transformation from the prepared N-(CH2-aryl)-N-(pyridin-2-yl)benzamides through debenzoylation to N-(CH2-aryl)-2-aminopyridine was successfully demonstrated.


Assuntos
Benzamidas , Paládio , Paládio/química , Catálise , Alquilação
8.
eNeuro ; 10(6)2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37253589

RESUMO

Synaptic modification in postnatal development is essential for the maturation of neural networks. Developmental maturation of excitatory synapses occurs at the loci of dendritic spines that are dynamically regulated by growth and pruning. Striatal spiny projection neurons (SPNs) receive excitatory input from the cerebral cortex and thalamus. SPNs of the striatonigral direct pathway (dSPNs) and SPNs of the striatopallidal indirect pathway (iSPNs) have different developmental roots and functions. The spatial and temporal dynamics of dendritic spine maturation of these two types of SPNs remain elusive. Here, we delineate the developmental trajectories of dendritic spines of dSPNs and iSPNs in the caudoputamen and nucleus accumbens (NAc). We labeled dendritic spines of SPNs by microinjecting Cre-dependent AAV-eYFP viruses into newborn Drd1-Cre or Adora2a-Cre mice, and analyzed spinogenesis at three levels, including different SPN cell types, subregions and postnatal times. In the dorsolateral striatum, spine pruning of dSPNs and iSPNs occurred at postnatal day (P)30-P50. In the dorsomedial striatum, the spine density of both dSPNs and iSPNs reached its peak between P30 and P50, and spine pruning occurred after P30 and P50, respectively, for dSPNs and iSPNs. In the NAc shell, spines of dSPNs and iSPNs were pruned after P21-P30, but no significant pruning was observed in iSPNs of lateral NAc shell. In the NAc core, the spine density of dSPNs and iSPNs reached its peak at P21 and P30, respectively, and subsequently declined. Collectively, the developmental maturation of dendritic spines in dSPNs and iSPNs follows distinct spatiotemporal trajectories in the dorsal and ventral striatum.


Assuntos
Espinhas Dendríticas , Núcleo Accumbens , Camundongos , Animais , Camundongos Transgênicos , Corpo Estriado/metabolismo , Neurônios/fisiologia
9.
Brain ; 146(8): 3542-3557, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37137515

RESUMO

Human speech and language are among the most complex motor and cognitive abilities. The discovery of a mutation in the transcription factor FOXP2 in KE family members with speech disturbances has been a landmark example of the genetic control of vocal communication in humans. Cellular mechanisms underlying this control have remained unclear. By leveraging FOXP2 mutation/deletion mouse models, we found that the KE family FOXP2R553H mutation directly disables intracellular dynein-dynactin 'protein motors' in the striatum by induction of a disruptive high level of dynactin1 that impairs TrkB endosome trafficking, microtubule dynamics, dendritic outgrowth and electrophysiological activity in striatal neurons alongside vocalization deficits. Dynactin1 knockdown in mice carrying FOXP2R553H mutations rescued these cellular abnormalities and improved vocalization. We suggest that FOXP2 controls vocal circuit formation by regulating protein motor homeostasis in striatal neurons, and that its disruption could contribute to the pathophysiology of FOXP2 mutation/deletion-associated speech disorders.


Assuntos
Corpo Estriado , Fala , Humanos , Camundongos , Animais , Fala/fisiologia , Corpo Estriado/metabolismo , Neurônios/metabolismo , Neostriado/metabolismo , Distúrbios da Fala , Mutação/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Vocalização Animal/fisiologia
10.
Small ; 19(2): e2203881, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36404110

RESUMO

Carbon@titania yolk-shell nanostructures are successfully synthesized at different calcination conditions. These unique structure nanomaterials can be used as a photocatalyst to degrade the emerging water pollutant, acetaminophen (paracetamol). The photodegradation analysis studies have shown that the samples with residual carbon nanospheres have improved the photocatalytic efficiency. The local electronic and atomic structure of the nanostructures are analyzed by X-ray absorption spectroscopy (XAS) measurements. The spectra confirm that the hollow shell has an anatase phase structure, slight lattice distortion, and variation in Ti 3d orbital orientation. In situ XAS measurements reveal that the existence of amorphous carbon nanospheres inside the nano spherical shell inhibit the recombination of electron-hole pairs; more mobile holes are formed in the p-d hybridized bands near the Fermi surface and enables the acceleration of the carries that significantly enhance the photodegradation of paracetamol under UV-visible irradiation. The observed charge transfer process from TiO2  hybridized orbital to the carbon nanospheres reduces the recombination rate of electrons and holes, thus increasing the photocatalytic efficiency.


Assuntos
Carbono , Nanoestruturas , Fotólise , Carbono/química , Acetaminofen , Espectroscopia por Absorção de Raios X , Catálise , Nanoestruturas/química
11.
Front Neuroanat ; 15: 669631, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054439

RESUMO

Schizophrenia is a devastating neuropsychiatric disease with a globally 1% life-long prevalence. Clinical studies have linked Zswim6 mutations to developmental and neurological diseases, including schizophrenia. Zswim6's function remains largely unknown. Given the involvement of Zswim6 in schizophrenia and schizophrenia as a neurodevelopmental disease, it is important to understand the spatiotemporal expression pattern of Zswim6 in the developing brain. Here, we performed a comprehensive analysis of the spatiotemporal expression pattern of Zswim6 in the mouse forebrain by in situ hybridization with radioactive and non-radioactive-labeled riboprobes. Zswim6 mRNA was detected as early as E11.5 in the ventral forebrain. At E11.5-E13.5, Zswim6 was highly expressed in the lateral ganglionic eminence (LGE). The LGE consisted of two progenitor populations. Dlx+;Er81+ cells in dorsal LGE comprised progenitors of olfactory bulb interneurons, whereas Dlx+;Isl1+ progenitors in ventral LGE gave rise to striatal projection neurons. Zswim6 was not colocalized with Er81 in the dorsal LGE. In the ventral LGE, Zswim6 was colocalized with striatal progenitor marker Nolz-1. Zswim6 was highly expressed in the subventricular zone (SVZ) of LGE in which progenitors undergo the transition from proliferation to differentiation. Double labeling showed that Zswim6 was not colocalized with proliferation marker Ki67 but was colocalized with differentiation marker Tuj1 in the SVZ, suggesting Zswim6 expression in early differentiating neurons. Zswim6 was also expressed in the adjacent structures of medial and caudal ganglionic eminences (MGE, CGE) that contained progenitors of cortical interneurons. At E15.5 and E17.5, Zswim6 was expressed in several key brain regions that were involved in the pathogenesis of schizophrenia, including the striatum, cerebral cortex, hippocampus, and medial habenular nucleus. Zswim6 was persistently expressed in the postnatal brain. Cell type analysis indicated that Zswim6 mRNA was colocalized with D1R-expressing striatonigral and D2R-expressing striatopallidal neurons of the adult striatum with a higher colocalization in striatopallidal neurons. These findings are of particular interest as striatal dopamine D2 receptors are known to be involved in the pathophysiology of schizophrenia. In summary, the comprehensive analysis provides an anatomical framework for the study of Zswim6 function and Zswim6-associated neurological disorders.

12.
Nano Lett ; 21(6): 2444-2452, 2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33651617

RESUMO

Silver, king among plasmonic materials, features low inelastic absorption in the visible-infrared (vis-IR) spectral region compared to other metals. In contrast, copper is commonly regarded as too lossy for actual applications. Here, we demonstrate vis-IR plasmons with quality factors >60 in long copper nanowires (NWs), as determined by electron energy-loss spectroscopy. We explain this result by noticing that most of the electromagnetic energy in these plasmons lies outside the metal, thus becoming less sensitive to inelastic absorption. Measurements for silver and copper NWs of different diameters allow us to elucidate the relative importance of radiative and nonradiative losses in plasmons spanning a wide spectral range down to <20 meV. Thermal population of such low-energy modes becomes significant and generates electron energy gains associated with plasmon absorption, rendering an experimental determination of the NW temperature. Copper is therefore emerging as an attractive, cheap, abundant material platform for high-quality plasmonics in elongated nanostructures.

13.
Nanomaterials (Basel) ; 10(10)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007846

RESUMO

Without using templates, seeds and surfactants, this study successfully prepared multi-oxide-layer coated Ag nanowires that enable tunable surface plasmon resonance without size or shape changes. A spontaneously grown ultra-thin titania layer onto the Ag nanowire surface causes a shift in surface plasmon resonance towards low energy (high wavelength) and also acts as a preferential site for the subsequent deposition of various oxides, e.g., TiO2 and CeO2. The difference in refractive indices results in further plasmonic resonance shifts. This verifies that the surface plasma resonance wavelength of one-dimensional nanostructures can be adjusted using refractive indices and shell oxide thickness design.

14.
J Comp Neurol ; 528(14): 2404-2419, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32144752

RESUMO

GABAergic interneurons play an essential role in modulating cortical networks. The progenitor domains of cortical interneurons are localized in developing ventral forebrain, including the medial ganglionic eminence (MGE), caudal ganglionic eminence (CGE), preoptic area (POA), and preoptic hypothalamic border domain (POH). Here, we characterized the expression pattern of Zswim5, an MGE-enriched gene in the mouse forebrain. At E11.5-E13.5, prominent Zswim5 expression was detected in the subventricular zone (SVZ) of MGE, POA, and POH, but not CGE of ventral telencephalon where progenitors of cortical interneurons resided. At E15.5 and E17.5, Zswim5 expression remained in the MGE/pallidum primordium and ventral germinal zone. Zswim5 mRNA was markedly decreased after birth and was absent in the adult forebrain. Interestingly, the Zswim5 expression pattern resembled the tangential migration pathways of cortical interneurons. Zswim5-positive cells in the MGE appeared to migrate from the MGE through the SVZ of LGE to overlying neocortex. Indeed, Zswim5 was co-localized with Nkx2.1 and Lhx6, markers of progenitors and migratory cortical interneurons. Double labeling showed that Ascl1/Mash1-positive cells co-expressed Zswim5. Zswim5 expressing cells contained none or at most low levels of Ki67 but co-expressed Tuj1 in the SVZ of MGE. These results suggest that Zswim5 is immediately upregulated as progenitors exiting cell cycle become postmitotic. Given that recent studies have elucidated that the cell fate of cortical interneurons is determined shortly after becoming postmitotic, the timing of Zswim5 expression in early postmitotic interneurons suggests a potential role of Zswim5 in regulation of neurogenesis and tangential migration of cortical interneurons.


Assuntos
Interneurônios/metabolismo , Neurogênese/fisiologia , Prosencéfalo/metabolismo , Fatores de Transcrição/metabolismo , Animais , Movimento Celular/fisiologia , Camundongos , Células-Tronco Neurais/metabolismo , Prosencéfalo/citologia , Transcriptoma , Dedos de Zinco/fisiologia
15.
Proc Natl Acad Sci U S A ; 117(13): 7418-7429, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32170006

RESUMO

The striatal complex of basal ganglia comprises two functionally distinct districts. The dorsal district controls motor and cognitive functions. The ventral district regulates the limbic function of motivation, reward, and emotion. The dorsoventral parcellation of the striatum also is of clinical importance as differential striatal pathophysiologies occur in Huntington's disease, Parkinson's disease, and drug addiction disorders. Despite these striking neurobiologic contrasts, it is largely unknown how the dorsal and ventral divisions of the striatum are set up. Here, we demonstrate that interactions between the two key transcription factors Nolz-1 and Dlx1/2 control the migratory paths of striatal neurons to the dorsal or ventral striatum. Moreover, these same transcription factors control the cell identity of striatal projection neurons in both the dorsal and the ventral striata including the D1-direct and D2-indirect pathways. We show that Nolz-1, through the I12b enhancer, represses Dlx1/2, allowing normal migration of striatal neurons to dorsal and ventral locations. We demonstrate that deletion, up-regulation, and down-regulation of Nolz-1 and Dlx1/2 can produce a striatal phenotype characterized by a withered dorsal striatum and an enlarged ventral striatum and that we can rescue this phenotype by manipulating the interactions between Nolz-1 and Dlx1/2 transcription factors. Our study indicates that the two-tier system of striatal complex is built by coupling of cell-type identity and migration and suggests that the fundamental basis for divisions of the striatum known to be differentially vulnerable at maturity is already encoded by the time embryonic striatal neurons begin their migrations into developing striata.


Assuntos
Gânglios da Base/citologia , Corpo Estriado/citologia , Estriado Ventral/citologia , Animais , Gânglios da Base/metabolismo , Diferenciação Celular , Corpo Estriado/metabolismo , Feminino , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Interneurônios/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Núcleo Accumbens/citologia , Núcleo Accumbens/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estriado Ventral/metabolismo
16.
Nanomaterials (Basel) ; 9(11)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671883

RESUMO

This study presents the preparation, characterization, and properties of a new composite containing cerium oxide nanoparticles and a conjugated polymer. CeO2 nanoparticles prepared using the co-precipitation method were dispersed into the conjugated polymer, prepared using the palladium-catalyzed Suzuki-Miyaura cross-coupling reaction. The interface interactions between the two components and the resultant optoelectronic properties of the composite are demonstrated. According to transmission electron microscopy and X-ray absorption spectroscopy, the dispersion of CeO2 nanoparticles in the polymer matrix strongly depends on the CeO2 nanoparticle concentration and results in different degrees of charge transfer. The photo-induced charge transfer and recombination processes were studied using steady-state optical spectroscopy, which shows a significant fluorescence quenching and red shifting in the composite. The higher photo-activity of the composite as compared to the single components was observed and explained. Unexpected room temperature ferromagnetism was observed in both components and all composites, of which the origin was attributed to the topology and defects.

17.
Nanoscale ; 11(8): 3574-3582, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30663762

RESUMO

We investigate the role of interfaces and surfaces in the magnetic and surface enhanced Raman spectroscopy (SERS) properties of CeO2 hollow spheres decorated with Ag nanoparticles (H-CeO2@Ag). The composites, H-CeO2@Ag, were synthesized using a newly developed two-step process. The CeO2 hollow sphere diameter ranges from 100 nm to 2 µm and the grafted Ag nanoparticle (NP) size varies from 5 to 50 nm with a controllable coverage ratio. Spectroscopic and microscopic characterization confirms the formation of an interface between the Ag and ceria and shows different charge rearrangements occurring at both the interface and the surface. Room temperature ferro-magnetism was observed in all composites, and is associated mostly with ceria surface defects. A strong SERS effect was reported with a detection limit down to 10-14 M for the rhodamine 6G analyte. Scanning transmission electron microscopy and electron energy loss spectroscopy investigation reveals that hot-spots are associated with the silver NP surfaces and also with the Ag/CeO2 interface. This interfacial hot spot occurs for metallic particles above 30 nm and is strongly red shifted with respect to the Ag surface plasmon. The strong SERS activity is then attributed to the presence of several types of hot-spots and the geometrical features (buoyant hollow sphere and size dispersion) of the composite.

18.
J Vis Exp ; (137)2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-30059031

RESUMO

Many genes are expressed in embryonic brains, and some of them are continuously expressed in the brain after birth. For such persistently expressed genes, they may function to regulate the developmental process and/or physiological function in neonatal brains. To investigate neurobiological functions of specific genes in the brain, it is essential to inactivate genes in the brain. Here, we describe a simple stereotaxic method to inactivate gene expression in the striatum of transgenic mice at neonatal time windows. AAV-eGFP-Cre viruses were microinjected into the striatum of Ai14 reporter gene mice at postnatal day (P) 2 by stereotaxic brain surgery. The tdTomato reporter gene expression was detected in P14 striatum, suggesting a successful Cre-loxP mediated DNA recombination in AAV-transduced striatal cells. We further validated this technique by microinjecting AAV-eGFP-Cre viruses into P2Foxp2fl/fl mice. Double labeling of GFP and Foxp2 showed that GFP-positive cells lacked Foxp2 immunoreactivity in P9 striatum, suggesting the loss of Foxp2 protein in AAV-eGFP-Cre transduced striatal cells. Taken together, these results demonstrate an effective genetic deletion by stereotaxically microinjected AAV-eGFP-Cre viruses in specific neuronal populations in the neonatal brains of floxed transgenic mice. In conclusion, our stereotaxic technique provides an easy and simple platform for genetic manipulation in neonatal mouse brains. The technique can not only be used to delete genes in specific regions of neonatal brains, but it also can be used to inject pharmacological drugs, neuronal tracers, genetically modified optogenetics and chemogenetics proteins, neuronal activity indicators and other reagents into the striatum of neonatal mouse brains.


Assuntos
Encéfalo/cirurgia , Corpo Estriado/cirurgia , Animais , Corpo Estriado/metabolismo , Expressão Gênica , Camundongos , Camundongos Transgênicos
19.
Neuroscience ; 388: 214-223, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30031127

RESUMO

Genetic mutations of FOXP1 and FOXP2 are associated with neurodevelopmental diseases. It is important to characterize the cell types that express Foxp1 and Foxp2 in the brain. Foxp1 and Foxp2 are expressed at high levels in the striatum of mouse brains. There are two populations of striatal projection neurons (SPNs), dopamine D1 receptor (D1R)-expressing striatonigral neurons and D2 receptor (D2R)-expressing striatopallidal neurons. In addition to SPNs, there are different types of striatal interneurons. Here, we quantitatively analyze the expression pattern of Foxp1 and Foxp2 with respect to specific cell types of projection neurons and interneurons in the striatum of adult mouse brains. Double immunostaining and in situ hybridization showed that Foxp1 and Foxp2 were specifically expressed in SPNs, but not in interneurons. For Foxp1, 50-57% of Foxp1-positive neurons co-expressed D1R mRNA, and 45-52% of Foxp1-positive neurons co-expressed D2R mRNA in the striatum at rostrocaudal levels. For Foxp2, 65-77% of Foxp2-positive neurons co-expressed D1R mRNA, and 21-26% of Foxp2-positive neurons co-expressed D2R mRNA in the striatum at rostrocaudal levels. Neither Foxp1 nor Foxp2 was found to co-localize with parvalbumin, somatostatin, nNOS, calretinin and ChAT in interneurons of the striatum. Moreover, none of parvalbumin-, somatostatin-, nNOS-, and calretinin-positive interneurons co-expressed Foxp1 or Foxp2 in the cerebral cortex. As Foxp1 and Foxp2 can form heterodimers for transcriptional regulation, the differential and overlapping expression pattern of Foxp1 and Foxp2 in SPNs implicates coordinate and distinct roles of Foxp1 and Foxp2 in developmental construction and physiologic functions of striatal circuits in the brain.


Assuntos
Corpo Estriado/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Neurônios/metabolismo , Proteínas Repressoras/metabolismo , Animais , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Corpo Estriado/citologia , Expressão Gênica , Camundongos Endogâmicos ICR , Neurônios/citologia , RNA Mensageiro/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo
20.
Nanoscale ; 9(30): 10764-10772, 2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28717799

RESUMO

Enhancement of room temperature ferromagnetism (RTFM) has been achieved with core-shell metal-oxide nanoparticles (Ag@CeO2). To enhance the magnetic properties, interfacial charge transfer is achieved via the formation of a core-shell interface. Furthermore, by varying the shell thicknesses, additional control of the RTFM can be obtained. The Ag@CeO2 core-shell nanoparticles are synthesized successfully via a two-step method. Ag nanoparticles (NPs) are first synthesized on a TiO2 substrate by a thermally assisted photoreduction method, and then CeO2 NPs are deposited on the surface of Ag NPs by chemical reduction. No surfactants or organic compounds are used during the synthesis. At the interface between the core and the shell, electron transfers from the Ag-p orbital to the Ag-d and Ce-f orbitals are evidenced by X-ray absorption spectroscopy and electron energy loss spectroscopy. Such interfacial charge transfer results in enhanced room temperature ferromagnetism in the Ag@CeO2 core-shell NPs compared to the magnetism arising for bare Ag or CeO2 NPs. This study suggests that tailoring the interface, the surface and their coupling in nanostructured metal-oxide core shell nanoparticles is an effective way to enhance their magnetic properties.

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