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1.
Nanotechnology ; 35(37)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38834034

RESUMO

We investigate the effects of oxygen vacancies on the ferroelectric behavior of Al:HfO2films annealed in O2and N2atmosphere. X-ray photoelectron spectroscopy results showed that the O/Hf atomic ratio was 1.88 for N2-annealed samples and 1.96 for O2-annealed samples, implying a neutralization of oxygen vacancies during O2atmosphere annealing. The O2-annealed films exhibited an increasing remanent polarization from 23µC cm-2to 28µC cm-2after 104cycles, with a negligible leakage current density of ∼2µA cm-2, while the remanent polarization decreased from 29µC cm-2to 20µC cm-2after cycling in the N2-annealed films, with its severe leakage current density decreasing from ∼1200µA cm-2to ∼300µA cm-2.A phase transition from the metastable tetragonal (t) phase to the low-temperature stable orthorhombic (o) phase and monoclinic (m) phase was observed during annealing. As a result of the fierce· competition between the t-to-o transition and the t-to-m transition, clear grain boundaries of several ruleless atomic layers were formed in the N2-annealed samples. On the other hand, the transition from the t-phase to the low-temperature stable phase was found to be hindered by the neutralization of oxygen vacancies, with almost continuous grain boundaries observed. The results elucidate the phase transformation caused by oxygen vacancies in the Al:HfO2films, which may be helpful for the preparation of HfO2-based films with excellent ferroelectricity.

2.
Eur Neurol ; : 1-12, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39074463

RESUMO

INTRODUCTION: Depression has been associated with cognitive performance, but whether sociodemographic and clinical characteristics might influence this association is not well elaborated. This study aimed to further explore this relationship in older adults. METHODS: This cross-sectional study is based on data from the National Health and Nutrition Examination Survey (NHANES) 2013-2014. A total of 1,433 individuals with complete information on depressive symptoms and cognitive function variables were included in this study. Patient Health Questionnaire 9 (PHQ-9) score ≥10 as the cutoff to identify cases of depression in our study. We defined poor cognitive performance as a composite cognitive score <47. Logistic regression models were used to examine the association of depression with cognitive performance (model 1). We progressively adjusted the covariates as confounders (model 2: model 1 + age, and gender; model 3: model 2 + race, education level, family income, drinking, and smoking; model 4: model 3 + overweight, arthritis, hyperlipidemia, diabetes, hypertension, heart failure, coronary heart disease, heart attack, stroke, and cancer). We then conducted subgroup, interaction, and restricted cubic spline (RCS) analyses to examine this association. RESULTS: The prevalence of poor cognitive performance was 36.6% (53/145) in the depression group and 14.1% (182/1,288) in the non-depression group. In the fully adjusted model, depression was significantly associated with poor cognitive performance (adjusted odds ratio: 2.25; 95% confidence interval: 1.31-3.81). The results were robust to sensitivity analyses. Gender and education level may modify the association between depression and poor cognitive performance. RCS analysis revealed that the PHQ-9 score was related to poor cognitive performance in a nonlinear manner (p for nonlinearity <0.001), and exhibited a J-shaped curve. CONCLUSION: Depression is associated with poor cognitive performance in US older adults. Early recognition and treatment of depression may be potential intervention strategies to protect cognitive health.

3.
J Neurosci ; 42(15): 3066-3079, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35197319

RESUMO

The NMDA subtype glutamate receptors (NMDARs) play important roles in both physiological and pathologic processes in the brain. Compared with their critical roles in synaptic modifications and excitotoxicity in excitatory neurons, much less is understood about the functional contributions of NMDARs to the inhibitory GABAergic neurons. By using selective NMDAR inhibitors and potentiators, we here show that NMDARs bidirectionally modulate the intrinsic excitability (defined as spontaneous/evoked spiking activity and EPSP-spike coupling) in inhibitory GABAergic neurons in adult male and female mice. This modulation depends on GluN2C/2D- but not GluN2A/2B-containing NMDARs. We further show that NMDAR modulator EU1794-4 mostly enhances extrasynaptic NMDAR activity, and by using it we demonstrate a significant contribution of extrasynaptic NMDARs to the modulation of intrinsic excitability in inhibitory neurons. Together, this bidirectional modulation of intrinsic excitability reveals a previously less appreciated importance of NMDARs in the second-to-second functioning of inhibitory GABAergic neurons.SIGNIFICANCE STATEMENT NMDA subtype of glutamate receptors (NMDARs) have important roles in brain functions, including both physiological and pathologic ones. The role of NMDARs in inhibitory neurons has been less elucidated compared with that in excitatory neurons. Our results demonstrate the importance of GluN2C/GluN2D-containing but not GluN2A/GluN2B-containing extrasynaptic NMDARs in modulating the intrinsic excitability of inhibitory neurons. These results further suggest distinct contributions of subsynaptic locations and subunit compositions of NMDARs to their functions in excitatory and inhibitory neurons. The above findings have implications for better understanding of brain diseases, such as schizophrenia.


Assuntos
N-Metilaspartato , Receptores de N-Metil-D-Aspartato , Animais , Feminino , Neurônios GABAérgicos , Ácido Glutâmico , Masculino , Camundongos , Sinapses/fisiologia
4.
Development ; 147(9)2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32291272

RESUMO

Powerful regeneration ability enables plant survival when plants are wounded. For example, adventitious roots can regenerate from the cutting site in detached Arabidopsis thaliana leaf explants, even in the absence of any exogenous plant hormone treatment. This process is known as de novo root regeneration (DNRR). Although the developmental program underlying DNRR is known, the precise regulatory mechanisms underlying DNRR are not completely understood. Here, we show that ethylene treatment or genetic activation of transcription factor ETHYLENE INSENSITIVE 3 (EIN3) strongly suppresses DNRR rates, while a mutant lacking EIN3 and its homolog EIL1 (ein3 eil1) displays a higher DNRR capacity. Previous reports have shown that the sequential induction of WUSCHEL RELATED HOMEOBOX 11 (WOX11)/WOX12 and WOX5/WOX7 expression is required for the establishment of DNRR. We found that EIN3 directly targets WOX11 and WOX5 promoter regions to suppress their transcription. Furthermore, older plants show enhanced EIN3 activity, and repressed expression of WOX11 and WOX5 Taken together, these results illustrate that plant aging at least partially takes advantage of EIN3 as a negative regulator to suppress DNRR through inhibiting the activation of WOX genes.


Assuntos
Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Western Blotting , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Etilenos/farmacologia , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Microscopia Confocal , Folhas de Planta/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Eur Neurol ; 86(1): 34-44, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36470230

RESUMO

INTRODUCTION: Constipation is a common nonmotor symptom of Parkinson's disease (PD) and has been reported to increase the risk of developing PD. However, previous studies have yielded conflicting results. Understanding this correlation may promote early diagnosis and treatment of PD, which could help patients improve their quality of life. This study aimed to investigate the association between constipation and PD onset. METHODS: The study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analyses of Observational Studies in Epidemiology (MOOSE) guidelines. We searched the Medline, Embase, Scopus, SINOMED, and Cochrane databases as well as specific journals from inception to September 2021 for observational studies that evaluated the association between constipation and the risk of PD. The Newcastle-Ottawa Scale was used to evaluate the methodological quality of the included studies. Associations were summarized as odds ratios (ORs) using a random-effects model. Subgroup, meta-regression, and sensitivity analyses were performed. RESULTS: Seventeen studies comprising 3,024,193 participants (case-control = 1,636,831; cohort = 1,387,362) were eligible for inclusion. The pooled OR for the association between constipation and PD was 2.36 (95% confidence interval: 1.93-2.88), although strong heterogeneity was observed (I2 = 90%, p < 0.01). Subgroup and meta-regression analyses indicated that study design and disease duration were the major sources of heterogeneity. A sensitivity analysis confirmed the stability of the outcomes. In addition, the prevalence of among those with prodromal PD was 20%, whereas it was only 11% in the control group (p < 0.01). Moreover, there were no significant age-based differences in constipation between the prodromal stage of PD patients and the controls (p > 0.05). CONCLUSION: Constipation has a relatively high incidence in the prodromal phase of PD and is associated with an increased risk of developing PD.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/epidemiologia , Qualidade de Vida , Constipação Intestinal/epidemiologia , Constipação Intestinal/etiologia , Incidência , Razão de Chances
6.
Postepy Dermatol Alergol ; 40(6): 734-740, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38282887

RESUMO

Introduction: Recent studies have confirmed the possibility of using upadacitinib for treating atopic dermatitis (AD). However, there is no meta-analysis to summarize and quantify the efficacy and safety of the drug, especially for adolescents with AD. Aim: To evaluate the overall efficacy and safety of upadacitinib in adults and adolescents with AD. Material and methods: We developed this systematic review and meta-analysis according to PRISMA guidelines. Risk-of-bias assessment tool, RoB2 (revised version 2019) was used for quality assessment. Results: Four RCTs were enrolled in the analysis, 3 of which on both adults and adolescents, while the other on adults only. For either adults or adolescents, the group treated with upadacitinib all had better performance than controls: EASI-75 (adults): RR = 4.68, 95% CI: 4.09, 5.35; NRS4 (adults): RR = 4.07, 95% CI: 3.15, 5.25; EASI-75 (adolescents): RR = 4.16, 95% CI: 2.70, 6.42; NRS4 (adolescents): RR = 4.52, 95% CI: 2.49, 8.21. Furthermore, upadacitinib 30 mg was more effective than 15 mg. For serious AEs, upper respiratory tract infection and headache, there was no significant difference between the upadacitinib group and controls. However, the treatment of upadacitinib may increase the risk of nasopharyngitis, increase blood creatine phosphokinase and cause acne. Conclusions: Upadacitinib seems to be a promising drug for AD. More long-term and larger-sized randomized clinical trials are required to further assess the safety and efficacy of upadacitinib for AD.

7.
Small ; 18(35): e2203292, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35859534

RESUMO

An effective therapeutic strategy against methicillin-resistant Staphylococcus aureus (MRSA) that does not promote further drug resistance is highly desirable. While phototherapies have demonstrated considerable promise, their application toward bacterial infections can be limited by negative off-target effects to healthy cells. Here, a smart targeted nanoformulation consisting of a liquid perfluorocarbon core stabilized by a lipid membrane coating is developed. Using vancomycin as a targeting agent, the platform is capable of specifically delivering an encapsulated photosensitizer along with oxygen to sites of MRSA infection, where high concentrations of pore-forming toxins trigger on-demand payload release. Upon subsequent near-infrared irradiation, local increases in temperature and reactive oxygen species effectively kill the bacteria. Additionally, the secreted toxins that are captured by the nanoformulation can be processed by resident immune cells to promote multiantigenic immunity that protects against secondary MRSA infections. Overall, the reported approach for the on-demand release of phototherapeutic agents into sites of infection could be applied against a wide range of high-priority pathogens.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Lipossomos/farmacologia , Testes de Sensibilidade Microbiana , Fototerapia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/prevenção & controle
8.
Nanotechnology ; 32(21)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33601350

RESUMO

The Al:HfO2ferroelectric nanofilms with different total thicknesses and distributions of Al-rich strips are prepared using atomic layer deposition (ALD) in an uncapped configuration. The synergistic interplay between the number of Al-rich layers and the thickness of total film offers the additional flexibility to boost the ferroelectricity of the resulting Al:HfO2nanofilms. By carefully optimizing both the ALD cycles for dopant layer and the total film thickness in the preparation, the HfO2nanofilms in post-deposition annealing can exhibit excellent ferroelectricity. The highest remanent polarization (2Pr) of 51.8µC cm-2is obtained in a 19.4 nm thick Al:HfO2nanofilm at the dopant concentration of 11.1 mol% with a three ALD cycles for Al-rich strips. Remarkable remanent polarization value observed in the uncapped electrode clamping film paves a new way to explore the origin of ferroelectricity in hafnium oxide nanofilms. The observed ferroelectricity of the nanofilm is affected neither by the presence of an interface between the upper electrode and the film nor the choices of the materials of upper electrode in the measurement, ensuring a high flexibility in the designing and fabrication of the relevant devices in the future.

9.
Neural Plast ; 2020: 8857543, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061953

RESUMO

The descending motor nerve conduction of voluntary swallowing is mainly launched by primary motor cortex (M1). M1 can activate and regulate peripheral nerves (hypoglossal) to control the swallowing. Acupuncture at "Lianquan" acupoint (CV23) has a positive effect against poststroke dysphagia (PSD). In previous work, we have demonstrated that electroacupuncture (EA) could regulate swallowing-related motor neurons and promote swallowing activity in the essential part of central pattern generator (CPG), containing nucleus ambiguus (NA), nucleus of the solitary tract (NTS), and ventrolateral medulla (VLM) under the physiological condition. In the present work, we have investigated the effects of EA on the PSD mice in vivo and sought evidence for PSD improvement by electrophysiology recording and laser speckle contrast imaging (LSCI). Four main conclusions can be drawn from our study: (i) EA may enhance the local field potential in noninfarction area of M1, activate the swallowing-related neurons (pyramidal cells), and increase the motor conduction of noninfarction area in voluntary swallowing; (ii) EA may improve the blood flow in both M1 on the healthy side and deglutition muscles and relieve PSD symptoms; (iii) EA could increase the motor conduction velocity (MCV) in hypoglossal nerve, enhance the EMG of mylohyoid muscle, alleviate the paralysis of swallowing muscles, release the substance P, and restore the ability to drink water; and (iv) EA can boost the functional compensation of M1 in the noninfarction side, strengthen the excitatory of hypoglossal nerve, and be involved in the voluntary swallowing neural control to improve PSD. This research provides a timely and necessary experimental evidence of the motor neural regulation in dysphagia after stroke by acupuncture in clinic.


Assuntos
Transtornos de Deglutição/fisiopatologia , Deglutição/fisiologia , Eletroacupuntura , Nervo Hipoglosso/fisiologia , Córtex Motor/fisiologia , Acidente Vascular Cerebral/complicações , Animais , Transtornos de Deglutição/etiologia , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL
10.
Glia ; 67(3): 525-538, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30506868

RESUMO

The identification of factors that regulate myelination provides important insight into the molecular mechanisms that coordinate nervous system development and myelin regeneration after injury. In this study, we investigated the role of amyloid precursor protein (APP) and its paralogue amyloid precursor-like protein 2 (APLP2) in myelination using APP and APLP2 knockout (KO) mice. Given that BACE1 regulates myelination and myelin sheath thickness in both the peripheral and central nervous systems, we sought to determine if APP and APLP2, as alternate BACE1 substrates, also modulate myelination, and therefore provide a better understanding of the events regulating axonal myelination. In the peripheral nervous system, we identified that adult, but not juvenile KO mice, have lower densities of myelinated axons in their sciatic nerves while in the central nervous system, axons within both the optic nerves and corpus callosum of both KO mice were significantly hypomyelinated compared to wild-type (WT) controls. Biochemical analysis demonstrated significant increases in BACE1 and myelin oligodendrocyte glycoprotein and decreased NRG1 and proteolipid protein levels in both KO brain tissue. The acute cuprizone model of demyelination/remyelination revealed that whereas axons in the corpus callosum of WT and APLP2-KO mice underwent similar degrees of demyelination and subsequent remyelination, the myelinated callosal axons in APP-KO mice were less susceptible to cuprizone-induced demyelination and showed a failure in remyelination after cuprizone withdrawal. These data identified APP and APLP2 as modulators of normal myelination and demyelination/remyelination conditions. Deletion of APP and APLP2 identifies novel interplays between the BACE1 substrates in the regulation of myelination.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Doenças Desmielinizantes/metabolismo , Bainha de Mielina/metabolismo , Remielinização/fisiologia , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Axônios/metabolismo , Corpo Caloso/metabolismo , Cuprizona , Doenças Desmielinizantes/induzido quimicamente , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Knockout , Oligodendroglia/metabolismo , Nervo Óptico/metabolismo
12.
Small ; 15(18): e1805308, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30938487

RESUMO

Assembling nanosized building blocks into macroscopic 3D complex structures is challenging. Here, nanosized metal and semiconductor building blocks with a variety of sizes and shapes (spheres, stars, and rods) are successfully assembled into a broad range of hierarchical (nanometer to micrometer) assemblies of functional materials in centimeter size using butterfly wings as templates. This is achieved by the introduction of steric hindrance to the assembly process, which compensates for attraction from the environmentally sensitive hydrogen bonds and prevents the aggregation of nanosized building blocks. Of these materials, Au nanostar assemblies show a superior enhancement in surface-enhanced Raman scattering (SERS) performance (rhodamine 6G, 1506 cm-1 ) under 532, 633, and 780 nm excitation-this is 3.1-4.4, 3.6-3.9, and 2.9-47.3 folds surpassing Au nanosphere assemblies and commercial SERS substrates (Q-SERS), respectively. This method provides a versatile route for the assembly of various nanosized building blocks into different 3D superstructures and for the construction of hybrid nanomaterials and nanocomposites.

13.
BMC Psychiatry ; 19(1): 314, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653237

RESUMO

BACKGROUND: N-methyl-D-aspartate receptor (NMDAR) hypofunction has been proposed to underlie the pathogenesis of schizophrenia. Specifically, reduced function of NMDARs leads to altered balance between excitation and inhibition which further drives neural network malfunctions. Clinical studies suggested that NMDAR modulators (glycine, D-serine, D-cycloserine and glycine transporter inhibitors) may be beneficial in treating schizophrenia patients. Preclinical evidence also suggested that these NMDAR modulators may enhance synaptic NMDAR function and synaptic plasticity in brain slices. However, an important issue that has not been addressed is whether these NMDAR modulators modulate neural activity/spiking in vivo. METHODS: By using in vivo calcium imaging and single unit recording, we tested the effect of D-cycloserine, sarcosine (glycine transporter 1 inhibitor) and glycine, on schizophrenia-like model mice. RESULTS: In vivo neural activity is significantly higher in the schizophrenia-like model mice, compared to control mice. D-cycloserine and sarcosine showed no significant effect on neural activity in the schizophrenia-like model mice. Glycine induced a large reduction in movement in home cage and reduced in vivo brain activity in control mice which prevented further analysis of its effect in schizophrenia-like model mice. CONCLUSIONS: We conclude that there is no significant impact of the tested NMDAR modulators on neural spiking in the schizophrenia-like model mice.


Assuntos
Ciclosserina/farmacologia , Lobo Frontal/efeitos dos fármacos , Sarcosina/farmacologia , Esquizofrenia/tratamento farmacológico , Animais , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Glicina/antagonistas & inibidores , Camundongos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Esquizofrenia/induzido quimicamente
14.
Angew Chem Int Ed Engl ; 57(21): 6115-6119, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29633442

RESUMO

MXenes, 2D compounds generated from layered bulk materials, have attracted significant attention in energy-related fields. However, most syntheses involve HF, which is highly corrosive and harmful to lithium-ion battery and supercapacitor performance. Here an alkali-assisted hydrothermal method is used to prepare a MXene Ti3 C2 Tx (T=OH, O). This route is inspired from a Bayer process used in bauxite refining. The process is free of fluorine and yields multilayer Ti3 C2 Tx with ca. 92 wt % in purity (using 27.5 m NaOH, 270 °C). Without the F terminations, the resulting Ti3 C2 Tx film electrode (ca. 52 µm in thickness, ca. 1.63 g cm-3 in density) is 314 F g-1 via gravimetric capacitance at 2 mV s-1 in 1 m H2 SO4 . This surpasses (by ca. 214 %) that of the multilayer Ti3 C2 Tx prepared via HF treatments. This fluorine-free method also provides an alkali-etching strategy for exploring new MXenes for which the interlayer amphoteric/acidic atoms from the pristine MAX phase must be removed.

15.
Neural Plast ; 2017: 2875904, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28163934

RESUMO

The N-methyl-D-aspartate receptors (NMDARs) are subtype glutamate receptors that play important roles in excitatory neurotransmission and synaptic plasticity. Their hypo- or hyperactivation are proposed to contribute to the genesis or progression of various brain diseases, including stroke, schizophrenia, depression, and Alzheimer's disease. Past efforts in targeting NMDARs for therapeutic intervention have largely been on inhibitors of NMDARs. In light of the discovery of NMDAR hypofunction in psychiatric disorders and perhaps Alzheimer's disease, efforts in boosting NMDAR activity/functions have surged in recent years. In this review, we will focus on enhancing NMDAR functions, especially on the recent progress in the generation of subunit-selective, allosteric positive modulators (PAMs) of NMDARs. We shall also discuss the usefulness of these newly developed NMDAR-PAMs.


Assuntos
Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/fisiologia , Regulação Alostérica/efeitos dos fármacos , Regulação Alostérica/fisiologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/fisiopatologia , Animais , Agonistas de Aminoácidos Excitatórios/farmacologia , Agonistas de Aminoácidos Excitatórios/uso terapêutico , Antagonistas de Aminoácidos Excitatórios/farmacologia , Humanos , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/fisiopatologia , Plasticidade Neuronal/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
16.
J Neurosci ; 34(42): 14128-46, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25319708

RESUMO

Parenchymal oligodendrocyte progenitor cells (pOPCs) are considered the principal cell type responsible for oligodendrogenesis and remyelinaton in demyelinating diseases. Recent studies have demonstrated that neural precursor cells (NPCs) from the adult subventricular zone (SVZ) can also generate new oligodendrocytes after demyelination. However, the relative contribution of NPCs versus pOPCs to remyelination is unknown. We used in vivo genetic fate mapping to assess the behavior of each progenitor type within the corpus callosi (CCs) of mice subjected to cuprizone-induced demyelination. Nestin-CreER(T2) and Pdgfra-CreER(T2) transgenic mice were crossed with fluorescent Cre reporter strains to map the fate of NPCs and pOPCs respectively. In cuprizone-challenged mice, substantial numbers of NPCs migrated into the demyelinated CC and contributed to oligodendrogenesis. This capacity was most prominent in rostral regions adjacent to the SVZ where NPC-derived oligodendrocytes significantly outnumbered those generated from pOPCs. Sixty-two percent of all nodes of Ranvier in this region were flanked by at least one paranode generated from an NPC-derived oligodendrocyte. Remarkably, g-ratios (ratio of the axon diameter to the diameter of the axon plus myelin sheath) of myelinated axons in regions subject to significant NPC-derived remyelination were equivalent to those of unchallenged controls, and immunoelectron microscopy revealed that NPC-derived myelin was significantly thicker than that generated by pOPCs, regardless of axonal caliber. We also demonstrate that a reduced efficiency of remyelination in the caudal CC was associated with long-term impairment in the maturation of oligodendrogenic NPCs but only transient delay in pOPC differentiation. Collectively, our data define a major distinct role for NPCs in remyelination, identifying them as a key target for enhancing myelin repair in demyelinating diseases.


Assuntos
Células-Tronco Adultas/fisiologia , Ventrículos Laterais/fisiologia , Bainha de Mielina/fisiologia , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/fisiologia , Oligodendroglia/fisiologia , Fatores Etários , Animais , Diferenciação Celular/fisiologia , Feminino , Ventrículos Laterais/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ratos
17.
Biology (Basel) ; 13(9)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39336105

RESUMO

Owing to global climate change or the ever-more frequent human activities in the offshore areas, it is highly probable that an imbalance in the offshore ecosystem has been induced. However, the importance of maintaining and protecting marine ecosystems' balance cannot be overstated. In recent years, various marine disasters have occurred frequently, such as harmful algal blooms (green tides and red tides), storm surge disasters, wave disasters, sea ice disasters, and tsunami disasters. Additionally, overpopulation of certain marine organisms (particularly marine faunas) has led to marine disasters, threatening both marine ecosystems and human safety. The marine ecological disaster monitoring system in China primarily focuses on monitoring and controlling the outbreak of green tides (mainly caused by outbreaks of some Ulva species) and red tides (mainly caused by outbreaks of some diatom and dinoflagellate species). Currently, there are outbreaks of Cnidaria (Hydrozoa and Scyphozoa organisms; outbreak species are frequently referred to as jellyfish), Annelida (Urechis unicinctus Drasche, 1880), Mollusca (Philine kinglipini S. Tchang, 1934), Arthropoda (Acetes chinensis Hansen, 1919), and Echinodermata (Asteroidea organisms, Ophiuroidea organisms, and Acaudina molpadioides Semper, 1867) in China. They not only cause significant damage to marine fisheries, tourism, coastal industries, and ship navigation but also have profound impacts on marine ecosystems, especially near nuclear power plants, sea bathing beaches, and infrastructures, posing threats to human lives. Therefore, this review provides a detailed introduction to the marine organisms (especially marine fauna species) causing marine biological disasters in China, the current outbreak situations, and the biological backgrounds of these outbreaks. This review also provides an analysis of the causes of these outbreaks. Furthermore, it presents future prospects for marine biological disasters, proposing corresponding measures and advocating for enhanced resource utilization and fundamental research. It is recommended that future efforts focus on improving the monitoring of marine biological disasters and integrating them into the marine ecological disaster monitoring system. The aim of this review is to offer reference information and constructive suggestions for enhancing future monitoring, early warning systems, and prevention efforts related to marine ecological disasters in support of the healthy development and stable operation of marine ecosystems.

18.
Sci Adv ; 10(1): eadf9951, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38170781

RESUMO

The main bottlenecks that hinder the performance of rechargeable zinc electrochemical cells are their limited cycle lifetime and energy density. To overcome these limitations, this work studied the mechanism of a dual-ion Zn-Cu electrolyte to suppress dendritic formation and extend the device cycle life while concurrently enhancing the utilization ratio of zinc and thereby increasing the energy density of zinc ion capacitors (ZICs). The ZICs achieved a best-in-class energy density of 41 watt hour per kilogram with a negative-to-positive (n/p) electrode capacity ratio of 3.10. At the n/p ratio of 5.93, the device showed a remarkable cycle life of 22,000 full charge-discharge cycles, which was equivalent to 557 hours of discharge. The cumulative capacity reached ~581 ampere hour per gram, surpassing the benchmarks of lithium and sodium ion capacitors and highlighting the promise of the dual-ion electrolyte for delivering high-performance, low-maintenance electrochemical energy supplies.

19.
Int J Nanomedicine ; 19: 8059-8070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39130687

RESUMO

Introduction: Asthma, a chronic respiratory disease closely associated with inflammation, presents ongoing treatment challenges. IALLIPF (le-Ala-Leu-Leu-Ile-Pro-Phe) is one of millet prolamins peptides (MPP) which shows anti-oxidant bioactivity by reducing the production of reactive oxygen species (ROS). Tryptophan (Trp, W) is an amino acid that has been demonstrated to possess anti-inflammatory effects. We introduce a novel cathepsin B-activatable bioactive peptides nanocarrier, PEG-IALLIPF-GFLG-W (MPP-Trp), designed for immunotherapy of asthma. Methods: MPP-Trp is synthesized, purified, and its characteristics are investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The yield of nitric oxide (NO) and pro-inflammatory cytokines (TNF-α, IL-6 and IL-1ß) are examined to evaluate anti-inflammatory effects of IALLIPF, Trp and MPP-Trp. The immunomodulatory effects of IALLIPF, Trp and MPP-Trp on Th1/Th2 cell populations and cytokines are investigated by flow cytometry, qRT-PCR and ELISA assays. We explore the therapeutic effect of MPP-Trp in the mouse model of asthma by the analysis of lung histology and ELISA. It is necessary to study the biocompatibility of MPP-Trp by CCK8 assay and histopathologic analysis using hematoxylin and eosin (HE) staining. Results: In asthmatic peripheral blood mononuclear cells (PBMCs), IALLIPF, Trp and MPP-Trp are able to significantly alleviate inflammation by inhibiting the yield of nitric oxide (NO) and pro-inflammatory cytokines (TNF-α, IL-6 and IL-1ß), especially MPP-Trp. MPP-Trp significantly upregulates Th1 cell levels while notably reducing Th2 cell levels. Furthermore, MPP-Trp effectively elevates the expression and production of interferon-gamma (IFN-γ), an essential cytokine from Th1 cells. Additionally, MPP-Trp markedly diminishes the mRNA expression and levels of key asthma pathogenesis cytokines, such as interleukin-4 (IL-4), interleukin-13 (IL-13), and interleukin-5 (IL-5), in asthma PBMCs. MPP-Trp ameliorates pulmonary pathological alterations and significantly inhibits OVA-induced inflammation in mice with asthma. It has little influence on the cell viability in Asthma-PBMCs treated with various concentrations or durations of MPP-Trp. No pathological changes, including in the heart, liver, spleen, lung, and kidney tissues, are observed in non-sensitized and non-challenged mice treated with MPP-Trp (20 mg/kg). Discussion: Our research demonstrates that MPP-Trp has immunomodulatory effects on Th1/Th2 cell populations, essential in managing asthma. It considerably alleviates OVA-induced asthma by shifting the immune response towards a Th1-dominant profile, thereby reducing Th2-driven inflammation. Therefore, this novel bioactive peptide nanocarrier, MPP-Trp, holds promise as a candidate for asthma immunotherapy.


Assuntos
Asma , Catepsina B , Citocinas , Imunoterapia , Animais , Asma/tratamento farmacológico , Asma/imunologia , Camundongos , Citocinas/metabolismo , Imunoterapia/métodos , Catepsina B/metabolismo , Camundongos Endogâmicos BALB C , Nanopartículas/química , Óxido Nítrico , Portadores de Fármacos/química , Feminino , Modelos Animais de Doenças , Pulmão/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/administração & dosagem , Células Th2/imunologia , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/administração & dosagem , Humanos , Triptofano/química , Triptofano/farmacologia , Triptofano/administração & dosagem , Células Th1/imunologia , Células Th1/efeitos dos fármacos
20.
CNS Neurosci Ther ; 30(3): e14442, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37665118

RESUMO

BACKGROUND: Post-stroke dysphagia (PSD), a common and serious disease, affects the quality of life of many patients and their families. Electroacupuncture (EA) has been commonly used effectively in the treatment of PSD, but the therapeutic mechanism is still under exploration at present. We aim to investigate the effect of the nucleus tractus solitarus (NTS) on the treatment of PSD by EA at Lianquan (CV23) through the primary motor cortex (M1). METHODS: C57 male mice were used to construct a PSD mouse model using photothrombotic technique, and the swallowing function was evaluated by electromyography (EMG) recording. C-Fos-positive neurons and types of neurons in the NTS were detected by immunofluorescence. Optogenetics and chemical genetics were used to regulate the NTS, and the firing rate of neurons was recorded via multichannel recording. RESULTS: The results showed that most of the activated neurons in the NTS were excitatory neurons, and multichannel recording indicated that the activity levels of both pyramidal neurons and interneurons in the NTS were regulated by M1. This process was involved in the EA treatment. Furthermore, while chemogenetic inhibition of the NTS reduced the EMG signal associated with the swallowing response induced by activation of M1 in PSD mice, EA rescued this signal. CONCLUSION: Overall, the NTS was shown to participate in the regulation of PSD by EA at CV23 through M1.


Assuntos
Transtornos de Deglutição , Eletroacupuntura , Córtex Motor , Humanos , Ratos , Masculino , Camundongos , Animais , Núcleo Solitário , Eletroacupuntura/métodos , Ratos Sprague-Dawley , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/terapia , Qualidade de Vida
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