Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 81
Filtrar
Mais filtros












Base de dados
Intervalo de ano de publicação
1.
Talanta ; 278: 126505, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38968658

RESUMO

This study developed a smartphone-based biosensor that could simultaneously detect and degrade aflatoxin B1 (AFB1). A donor-acceptor covalent organic framework (COF) was bound onto the surface of stainless-steel mesh (SSM) via the in-situ synthesis, which was used to immobilize the aptamer (Apt) to specifically capture AFB1 and was also as a photocatalyst to degrade AFB1. Au@Ir nanospheres were synthesized, which exhibited better peroxidase catalytic activity (Km=5.36 × 10-6 M, Vmax=3.48 × 10-7 Ms-1, Kcat=1.00 × 107 s-1) than Ir@Au nanospheres, so Au@Ir nanospheres were linked with Apt2 to be utilized as the signal probe. The density functional theory calculation also described that Au@Ir nanospheres possessed the lower energy barriers to decompose H2O2 than Ir@Au nanospheres. Coupled with the "Color Picker" application in the smartphone, the established "sandwich-structure" colorimetric method exhibited a linear range of 0.5-200 µg L-1 and a detection limit of 0.045 µg L-1. The photocatalytic capacity of SSM/COF towards AFB1 was investigated and the degradation rate researched 81.14 % within 120 min under the xenon lamp irradiation, and the degradation products were validated by ESI-MS. It was applied for the detection of AFB1 in peanuts, corn, and wheat samples. Recoveries were ranging from 77.90 % to 112.5 %, and the matrix effect was 75.10-111.6 %. Therefore, the smartphone-based biosensor provided a simple, fast, and sensitive platform for the detection of AFB1, and meanwhile could realize the efficient degradation of AFB1.

2.
PLoS One ; 19(7): e0307148, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39018283

RESUMO

The karst plateau is dominated by mountainous and hilly landforms, with low mechanization level of cropland, high difficulty of cultivation, and obvious phenomenon of cropland abandonment, which threatens regional food security. This study aims to analyze the spatial-temporal variation and its driving mechanisms of abandoned cropland in the Karst Plateau in Eastern Yunnan, China (KPEYC) between 2001 and 2020. To achieve this goal, 18 key factors from population, economic environment, cropland attributes, and farming conditions are selected. Moreover, correlation analysis, geodetector, and regression analysis methods are applied from three perspectives: temporal change, spatial distribution and spatial-temporal change. The results show that: (i) The cropland abandonment rate (CAR) in the KPEYC shows a fluctuating trend, with an average value of 9.78%, and the spatial distribution shows a pattern of "high in the center and low in the south and north". (ii) From the perspective of temporal change, gross value of agricultural production, and gross value of industrial production have the largest correlation coefficients with CAR. (iii) The explanatory power of gross tertiary industrial production, gross value of industrial production, followed by soil thickness. (iv) Gross value of agricultural production, and gross tertiary industrial production are the core driving forces for the spatial-temporal change of CAR. The higher the gross value of agricultural production and gross tertiary industrial production, the lower the CAR. elevation, soil thickness, and traffic mileage are the main driving factors for the spatial-temporal change of CAR. The study indicates that economic factors are decisive for cropland abandonment in the KPEYC. Based on the results, this study can provide decision-making support for local prevention and control of cropland abandonment, and the local community needs to promote land transfer and concentration and local urbanization according to local conditions, improve agricultural policies, improve farming conditions, etc. in order to increase farmers' enthusiasm for production, promote the rational use of cropland, and solidly push forward ecological restoration and management, optimize ecological spatial patterns, manage serious areas of rocky desertification, and appropriately alleviate the contradiction between people and land.


Assuntos
Agricultura , Análise Espaço-Temporal , China , Produtos Agrícolas/crescimento & desenvolvimento , Humanos , Conservação dos Recursos Naturais , Solo
3.
Sci Total Environ ; 945: 174136, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38901578

RESUMO

Dioxins and the emerging dioxin-like compounds (DLCs) have recruited increasing concerns about their environmental contamination, toxicity, health impacts, and mechanisms. Based on the structural similarity of dioxins and many DLCs, their toxicity was predominantly mediated by the dioxin receptor (aryl hydrocarbon receptor, AHR) in animals (including human), which can be different in expression and function among species and then possibly produce the species-specific risk or toxicity. To date, characterizing the AHR of additional species other than human and rodents can increase the accuracy of toxicity/risk evaluation and increase knowledge about AHR biology. As a key model, the medaka AHR has not been clearly characterized. Through genome survey and phylogenetic analysis, we identified four AHRs (olaAHR1a, olaAHR1b, olaAHR2a, and olaAHR2b) and two ARNTs (olaARNT1 and olaARNT2). The medaka AHR pathway was conserved in expression in nine tested tissues, of which olaAHR2a represented the predominant subform with greater abundance. Medaka AHRs and ARNTs were functional and could be efficiently transactivated by the classical dioxin congener 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), although olaAHR1a did not seem to cooperate with olaARNT2. In terms of function/sensitivity, the EC50 values of medaka olaAHR1a (9.01 ± 1.43 nM), olaAHR1b (4.00 ± 1.10 nM), olaAHR2a (8.75 ± 3.34 nM), and olaAHR2b (3.06 ± 0.81 nM) showed slight differences; however, they were all at the nM level. The sensitivity of four medaka AHRs to TCDD was similar to that of zebrafish dreAHR2 (the dominant form, EC50 = 3.14 ± 4.19 nM), but these medaka AHRs were more sensitive than zebrafish dreAHR1b (EC50 = 27.05 ± 18.51 nM). The additional comparison also indicated that the EC50 values in various species were usually within the nM range, but AHRs of certain subforms/species can vary by one or two orders of magnitude. In summary, the present study will enhance the understanding of AHR and help improve research on the ecotoxicity of dioxins/DLCs.


Assuntos
Dioxinas , Oryzias , Receptores de Hidrocarboneto Arílico , Poluentes Químicos da Água , Peixe-Zebra , Animais , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Dioxinas/toxicidade , Poluentes Químicos da Água/toxicidade , Filogenia , Especificidade da Espécie
4.
Psychol Addict Behav ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780582

RESUMO

OBJECTIVE: The rising prevalence of daily cannabis use among older adolescents and young adults in the United States has significant public health implications. As a result, more individuals may be seeking or in need of treatment for adverse outcomes (e.g., cannabis use disorder) arising from excessive cannabis use. Our objective was to explore the potential of self-reported motives for cannabis use as a foundation for developing adaptive interventions tailored to reduce cannabis consumption over time or in certain circumstances. We aimed to understand how transitions in these motives, which can be collected with varying frequencies (yearly, monthly, daily), predict the frequency and adverse outcomes of cannabis use. METHOD: We conducted secondary analyses on data collected at different frequencies from four studies: the Medical Cannabis Certification Cohort Study (n = 801, biannually), the Cannabis, Health, and Young Adults Project (n = 359, annually), the Monitoring the Future Panel Study (n = 7,851, biennially), and the Text Messaging Study (n = 87, daily). These studies collected time-varying motives for cannabis use and distal measures of cannabis use from adolescents, young adults, and adults. We applied latent transition analysis with random intercepts to analyze the data. RESULTS: We identified the types of transitions in latent motive classes that are predictive of adverse outcomes in the future, specifically transitions into or staying in classes characterized by multiple motives. CONCLUSIONS: The identification of such transitions has direct implications for the development of adaptive interventions designed to prevent adverse health outcomes related to cannabis use. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

5.
Hum Mol Genet ; 33(11): 969-980, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38483349

RESUMO

RNA methylation of N6-methyladenosine (m6A) is emerging as a fundamental regulator of every aspect of RNA biology. RNA methylation directly impacts protein production to achieve quick modulation of dynamic biological processes. However, whether RNA methylation regulates mitochondrial function is not known, especially in neuronal cells which require a high energy supply and quick reactive responses. Here we show that m6A RNA methylation regulates mitochondrial function through promoting nuclear-encoded mitochondrial complex subunit RNA translation. Conditional genetic knockout of m6A RNA methyltransferase Mettl14 (Methyltransferase like 14) by Nestin-Cre together with metabolomic analysis reveals that Mettl14 knockout-induced m6A depletion significantly downregulates metabolites related to energy metabolism. Furthermore, transcriptome-wide RNA methylation profiling of wild type and Mettl14 knockout mouse brains by m6A-Seq shows enrichment of methylation on mitochondria-related RNA. Importantly, loss of m6A leads to a significant reduction in mitochondrial respiratory capacity and membrane potential. These functional defects are paralleled by the reduced expression of mitochondrial electron transport chain complexes, as well as decreased mitochondrial super-complex assembly and activity. Mechanistically, m6A depletion decreases the translational efficiency of methylated RNA encoding mitochondrial complex subunits through reducing their association with polysomes, while not affecting RNA stability. Together, these findings reveal a novel role for RNA methylation in regulating mitochondrial function. Given that mitochondrial dysfunction and RNA methylation have been increasingly implicate in neurodegenerative disorders, our findings not only provide insights into fundamental mechanisms regulating mitochondrial function, but also open up new avenues for understanding the pathogenesis of neurological diseases.


Assuntos
Adenosina , Metiltransferases , Camundongos Knockout , Mitocôndrias , Animais , Mitocôndrias/metabolismo , Mitocôndrias/genética , Camundongos , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/genética , RNA/genética , RNA/metabolismo , Humanos , Biossíntese de Proteínas , Metabolismo Energético/genética , Neurônios/metabolismo , Metilação de RNA
6.
MedComm (2020) ; 5(4): e514, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38495123

RESUMO

Electrical brain stimulation (EBS) has gained popularity for laboratory and clinical applications. However, comprehensive characterization of cellular diversity and gene expression changes induced by EBS remains limited, particularly with respect to specific brain regions and stimulation sites. Here, we presented the initial single-nucleus RNA sequencing profiles of rat cortex, hippocampus, and thalamus subjected to intracranial alternating current stimulation (iACS) at 40 Hz. The results demonstrated an increased number of neurons in all three regions in response to iACS. Interestingly, less than 0.1% of host gene expression in neurons was significantly altered by iACS. In addition, we identified Rgs9, a known negative regulator of dopaminergic signaling, as a unique downregulated gene in neurons. Unilateral iACS produced a more focused local effect in attenuating the proportion of Rgs9+ neurons in the ipsilateral compared to bilateral iACS treatment. The results suggested that unilateral iACS at 40 Hz was an efficient approach to increase the number of neurons and downregulate Rgs9 gene expression without affecting other cell types or genes in the brain. Our study presented the direct evidence that EBS could boost cerebral neurogenesis and enhance neuronal sensitization to dopaminergic drugs and agonists, through its downregulatory effect on Rgs9 in neurons.

7.
Indian J Pathol Microbiol ; 66(4): 799-803, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38084535

RESUMO

Context: Squalene epoxidase (SQLE) is overexpressed in a variety of tumors, which may play an important role in their tumorigenesis, development, and prognosis. Aims: The aim of this study is to investigate the expression of SQLE and explore its clinicopathological significance in gastric cancer. Settings and Design: The correlation between its positive expression and the pathological characteristics of patients (such as sex, age, tumor size, survival, tumor differentiation, TNM staging, and lymph node metastasis) was analyzed. Materials and Methods: Immunohistochemical method was used to detect its expression in 107 cases of gastric carcinoma and 34 cases of tumor-adjacent tissues. Statistical Analysis Used: Counting data were analyzed by Chi-square test. Its overall survival was analyzed by Kaplan-Meier method and log-rank test. Its hazard factors were analyzed by Cox multivariate analysis. Results: The positive rate of SQLE in gastric cancer is 67.3%, which is higher than that in tumor-adjacent tissues (17.6%), <0.001. Expression of SQLE is closely related to tumor differentiation, TNM staging and lymph node metastasis (P = 0.030, P = 0.009, and P = 0.011, respectively). Furthermore, compared with those low expression of SQLE, the patients of overexpression had worse overall survival by Kaplan-Meier analysis (P = 0.025). Cox multivariate analysis shows that lymph node metastasis, tumor differentiation, SQLE, and TNM staging are independent factors for prognosis of gastric cancer (P = 0.003, 0.020, 0.018, and P = 0.001 respectively). Conclusions: SQLE is overexpressed in gastric cancer. It could be used for the diagnosis and prognosis of the gastric cancer patients.


Assuntos
Esqualeno Mono-Oxigenase , Neoplasias Gástricas , Humanos , Relevância Clínica , Metástase Linfática , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/genética
8.
Proc Natl Acad Sci U S A ; 120(47): e2300308120, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37976261

RESUMO

Spinal muscular atrophy (SMA), the top genetic cause of infant mortality, is characterized by motor neuron degeneration. Mechanisms underlying SMA pathogenesis remain largely unknown. Here, we report that the activity of cyclin-dependent kinase 5 (Cdk5) and the conversion of its activating subunit p35 to the more potent activator p25 are significantly up-regulated in mouse models and human induced pluripotent stem cell (iPSC) models of SMA. The increase of Cdk5 activity occurs before the onset of SMA phenotypes, suggesting that it may be an initiator of the disease. Importantly, aberrant Cdk5 activation causes mitochondrial defects and motor neuron degeneration, as the genetic knockout of p35 in an SMA mouse model rescues mitochondrial transport and fragmentation defects, and alleviates SMA phenotypes including motor neuron hyperexcitability, loss of excitatory synapses, neuromuscular junction denervation, and motor neuron degeneration. Inhibition of the Cdk5 signaling pathway reduces the degeneration of motor neurons derived from SMA mice and human SMA iPSCs. Altogether, our studies reveal a critical role for the aberrant activation of Cdk5 in SMA pathogenesis and suggest a potential target for therapeutic intervention.


Assuntos
Células-Tronco Pluripotentes Induzidas , Atrofia Muscular Espinal , Animais , Humanos , Camundongos , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Modelos Animais de Doenças , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios Motores/metabolismo , Atrofia Muscular Espinal/metabolismo , Degeneração Neural/patologia , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo
9.
Anal Methods ; 15(47): 6551-6560, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-37997770

RESUMO

Real-time quantitative analysis of tetracyclines is urgently needed to provide consumers with early warning of potential risks. Herein, we report a dual-mode green emissive fluorescent probe, which refers to the liquid mode and the solid mode of electrospun films doped with nitride-doped carbon nanosheets (NCNSs) for real-time detection of doxycycline (DOX). Highly fluorescent NCNSs were prepared by low-temperature solid treatment of urea and sodium citrate. With the addition of DOX, the green emission intensity of NCNSs at 475 nm can be obviously reduced. Method validation exhibited a good linear relationship in 0.05-150 µM between the fluorescence quenching of NCNSs and the concentration of DOX with a limit of detection (LOD) of 0.0127 µM. Furthermore, the immobilization of NCNSs in PAN carriers forming electrospun films stabilizes the green fluorescence of NCNSs. Additionally, electrospun films integrated into a smartphone were developed for real-time detection of DOX with LOD of 0.285 µM. Additionally, DOX in milk was monitored with satisfactory recoveries. Therefore, the integration of the smartphone and electrospun film provides a promising and convenient method for real-time identification of DOX in food analysis.


Assuntos
Doxiciclina , Corantes Fluorescentes , Animais , Doxiciclina/análise , Leite/química , Smartphone , Antibacterianos/análise
10.
Sci Total Environ ; 904: 166622, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37647967

RESUMO

Tetrabromobisphenol A (TBBPA) is a widely used plastic additive with high bioaccumulation potential and toxicity on both humans and wildlife. Currently, research on its ecotoxicity and the underlying mechanism is limited. Using common carp (Cyprinus carpio), we evaluated the toxicity of TBBPA, especially focusing on its alteration of a key metabolism-related pathway aryl hydrocarbon receptor (AHR), using in vivo/vitro assays and in silico simulation. The 96 h LC50 of TBBPA of common carp was 4.2 mg/L and belonged to the acute toxic level II. The bioaccumulation potential of TBBPA follows the role of liver > gill > brain and varies between 3- and 14-day exposure. On the AHR pathway respect, as expected, the metabolism-related cyp1a1 and cyp1b1 were upregulated in the liver and brain. Ahr2, the receptor, was also upregulated in the brain under TBBPA exposure. The alteration of gene expression was tissue-specific while the difference between 3- or 14-day exposure was minor. AHR inhibition assay indicated the 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)-induced AHR transactivation can be inhibited by TBBPA suggesting it is not a potent agonist but a competitive antagonist. In silico analysis indicated TBBPA can be successfully docked into the binding cavity with similar poses but still have AHR-form-specific interactions. Molecular dynamics simulation proved TBBPA can be more flexible than the coplanar ligand TCDD, especially in ccaAHR1b with greater root-mean-square deviation (RMSD), of which TCDD-induced transactivation seemed not to be blocked by TBBPA. This research increased the understanding of TBBPA toxicity and alteration of the AHR pathway, and pointed out the need to perform additional toxicology evaluation of emerging contaminants, especially on non-model species.


Assuntos
Carpas , Dibenzodioxinas Policloradas , Animais , Humanos , Receptores de Hidrocarboneto Arílico/metabolismo , Carpas/metabolismo , Fígado/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Citocromo P-450 CYP1A1/metabolismo
11.
Psychol Res Behav Manag ; 16: 2417-2424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426390

RESUMO

Objective: This study aimed to investigate the impact of academic self-efficacy on test anxiety among higher vocational students, as well as the role of sense of life meaning, fear of failure, and gender difference in mediating this relationship. Methods: A total of 2231 higher vocational students from Shandong Province were surveyed by means of Academic Self-efficacy Questionnaire, Meaning in Life Questionnaire, and Test Anxiety Scale. Results: There were significant negative correlations among academic self-efficacy, sense of life meaning, and test anxiety. Fear of failure was positively correlated with test anxiety. Sense of life meaning and fear of failure played a mediating role in the relationship between academic self-efficacy and test anxiety. The chain mediating effect was significant only in the female group, not in the male group. In contrast, academic self-efficacy indirectly predicted test anxiety by the independent mediating effect of sense of life meaning or fear of failure in the male group. Conclusion: Academic self-efficacy may influence test anxiety through the independent mediating effect of sense of life meaning, fear of failure, and the chain mediating effect, and there is a gender difference in these effects.

12.
Sci Total Environ ; 884: 163809, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37127157

RESUMO

Dioxins are widely known to bioaccumulate in the body and produce a wide spectrum of toxic effects on both humans and wildlife. In addition, some novel sorts of compounds that were similar in structure and effect were gradually identified and termed dioxin-like compounds (DLCs). The toxicity of dioxins as well as DLCs is predominantly mediated by the dioxin receptor (aryl hydrocarbon receptor, AHR) in animals, which is usually differentially expressed and functionally distinct (especially the sensitivity to dioxins) among species, possibly resulting in species-specific variations in the toxicity of dioxins. Therefore, detailed functional exploration of the AHRs of a given species, such as the common carp (which is a vital wild and commercial species with a broad geological distribution) in the current study, will enable a comprehensive ecotoxicity evaluation. Through genome survey and phylogenetic analysis, we identified three AHRs (AHR1a, AHR1b, and AHR2) and two ARNTs (ARNT1 and ARNT2). AHR2 was observed to have greater expression abundance in the gill and brain, and may serve as the predominant subform. Those AHRs and ARNTs are functional, and the AHRs can be efficiently transactivated by the classical dioxin congener 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). We individually determined the EC50 values of AHR1a (0.41 ± 0.24 nM), AHR1b (12.80 ± 3.28 nM), and AHR2 (0.64 ± 0.49 nM), and found that: 1) The AHR sensitivities of common carp and zebrafish (phylogenetically close species) are relatively similar. AHR1a and the predominant form AHR2 have greater sensitivity to TCDD. 2) ARNT1 and ARNT2 do not produce different sensitivities, but with distinct induction fold, of a given AHR transactivation when cooperating as the partner; 3) Distinct AHR subforms of the same or distinct species can have even one or two orders of magnitude differences in sensitivity. In summary, the current study will add to the knowledge of AHR biology and help improve ecotoxicology research on dioxins and DLCs.


Assuntos
Carpas , Dioxinas , Dibenzodioxinas Policloradas , Humanos , Animais , Dioxinas/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Peixe-Zebra/metabolismo , Carpas/metabolismo , Filogenia , Dibenzodioxinas Policloradas/metabolismo
13.
Food Chem ; 422: 136263, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37141755

RESUMO

The content of food colorant in food and environment should be limited to a safe range. Thus, cost-effective, and environmental-friendly detoxification technology is urgent for food safety and environmental protection. In this work, defective-functionalized g-C3N4 was successfully fabricated via intermediate engineering strategy. The prepared g-C3N4 possesses large specific surface area with abundant in-plane pores. Carbon vacancy and N-CO unit are introduced into g-C3N4 molecular framework, endowing the different degrees of n-type conductivity in varied domains. And then the n-n homojunction is generated. This homojunction structure is demonstrated to be efficient in separation and transfer of photoinduced charge carriers, and causes enhanced photocatalytic detoxification of lemon yellow under visible light. Furthermore, as-prepared g-C3N4 in lemon tea enable completely removed lemon yellow without obvious effect on its overall acceptability. The findings deepen the understanding on the defect-induced self-functionality of g-C3N4, and prove the application potential of photocatalytic technology in contaminated beverages.


Assuntos
Luz , Água , Catálise , Carbono , Bebidas
14.
Scientometrics ; 128(4): 2105-2143, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37095862

RESUMO

"Achieve gender equality and empower all women and girls" is essential to reduce gender disparity and improve the status of women. But it remains a challenge to narrow gender differences and improve gender equality in academic research. In this paper, we propose that the impact of articles is lower and writing style of articles is less positive when the article's first author is female relative to male first authors, and writing style mediates this relationship. Focusing on the positive writing style, we attempt to contribute and explain the research on gender differences in research performance. We use BERT-based textual sentiment analysis to analyse 87 years of 9820 articles published in the top four marketing journals and prove our hypotheses. We also consider a set of control variables and conduct a set of robustness checks to ensure the robustness of our findings. We discuss the theoretical and managerial implications of our findings for researchers. Supplementary Information: The online version contains supplementary material available at 10.1007/s11192-023-04666-w.

15.
J Control Release ; 357: 196-209, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36921724

RESUMO

Poly (lactic-co-glycolic acid) (PLGA) microspheres have been one of the most successful products for slow drug release. While distribution of drugs in microspheres might be a fundamental factor affecting drug release, it has been often overlooked. Indeed, very few studies are available on the distribution of drugs in microspheres with complex morphology like golf ball-shaped microspheres. In this paper, the distribution of rotigotine in golf ball-shaped microspheres (GSRM) was investigated by argon ion milling, combined with scanning electron microscopy and energy dispersive X-ray spectroscopy (AIM-SEM-EDS). Rotigotine in GSRM was clearly observed in two forms, respectively in an aggregated state and as a molecular dispersion. The distribution of palmitic acid in the microspheres (used as an additive to reduce burst release) was also demonstrated: 10% was found on the microspheres' surface while 90% separated from the polymer to form small particles inside the microspheres onto which rotigotine aggregated through hydrogen bonding interactions. In in-vitro release studies we observed that first the phase-separated palmitic acid/rotigotine particles dissolved and released the drug, followed by the release of the molecularly dispersed rotigotines by osmosis. We also found that rotigotine accelerated the degradation and reduced the glass transition temperature of PLGA, which played an important role as well in the release of the drug from GSRM. Finally, two linear Level A in vitro-in vivo correlations were established and validated, indicating that the in vitro release testing could be a meaningful predictor for the in vivo performance of GSRM. Our work demonstrates the importance of studying drug distribution in complex microspheres to understand drug release.


Assuntos
Golfe , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ácido Poliglicólico/química , Ácido Láctico/química , Microesferas , Liberação Controlada de Fármacos , Ácido Palmítico , Tamanho da Partícula , Microscopia Eletrônica de Varredura
16.
Mol Biol Cell ; 34(4): br5, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36753381

RESUMO

Centromeres are known to cluster around nucleoli in Drosophila and mammalian cells, but the significance of the nucleoli-centromere interaction remains underexplored. To determine whether the interaction is dynamic under different physiological and pathological conditions, we examined nucleolar structure and centromeres at various differentiation stages using cell culture models and the results showed dynamic changes in nucleolar characteristics and nucleoli-centromere interactions through differentiation and in cancer cells. Embryonic stem cells usually have a single large nucleolus, which is clustered with a high percentage of centromeres. As cells differentiate into intermediate states, the nucleolar number increases and the centromere association decreases. In terminally differentiated cells, including myotubes, neurons, and keratinocytes, the number of nucleoli and their association with centromeres are at the lowest. Cancer cells demonstrate the pattern of nucleoli number and nucleoli-centromere association that is akin to proliferative cell types, suggesting that nucleolar reorganization and changes in nucleoli-centromere interactions may play a role in facilitating malignant transformation. This idea is supported in a case of pediatric rhabdomyosarcoma, in which induced differentiation reduces the nucleolar number and centromere association. These findings suggest active roles of nucleolar structure in centromere function and genome organization critical for cellular function in both normal development and cancer.


Assuntos
Nucléolo Celular , Neoplasias , Animais , Nucléolo Celular/metabolismo , Centrômero , Núcleo Celular/metabolismo , Mamíferos , Neoplasias/metabolismo
17.
Aquat Toxicol ; 248: 106171, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35504175

RESUMO

Due to the production of large quantities of electronic waste (e-waste), unsafe dismantling has caused serious pollution as well as toxicological impacts on both wildlife and humans. As an important aspect of physiology and health, the wildlife's gut microbiota and its changes induced by pollution have been recruiting increasing concerns. To reveal the gut microbiota-related ecotoxicology induced by e-waste dismantling, this study resolves the gut microbiota profile of Anabas testudineus, a native highly adapted nonmodel fish under the in situ exposure, and reveals whether and how the microbiota was altered. The comparisons are made by collecting samples from different e-waste polluted sites in Guiyu (a town in South China) and a nearby reference (nonpolluted) site. The overall gut microbiota landscape of A. testudineus is similar to that of other reported fishes, with an average of ∼300 OTUs, and constituted by Firmicutes (34.51%), Fusobacteria (29.16%) as the major phyla. Obviously different liver metal burdens/fingerprints were observed between the e-waste and reference sites. Accordingly, although the alpha-diversity (ACE, Simpson, and Shannon) of the gut microbiota did not significantly vary, a detailed exploration of the microbiota constitution indicated significant differences at various taxonomic levels, including a series of significantly different species and biomarkers, and showing site-specific beta-diversity clustering patterns. Interestingly, a few bacteria with greater abundance in the fish gut of e-waste polluted sites were also reported to present in other contaminated environments, have a role in wastewater treatment, be capable to transform metal, etc. Redundancy analysis (RDA) and Pearson association analyses indicated significant associations between Mn and Cetobacterium somerae (Pearson r = 0.3612, p = 0.0008) and between Pb and Clostridium colicanis (Pearson r = 0.5151, p < 0.0001). In summary, pollution from e-waste dismantling may have a role in altering the fish gut microbiota, and this research provides insights for better understanding e-waste ecotoxicology and improving future conservation.


Assuntos
Resíduo Eletrônico , Microbioma Gastrointestinal , Microbiota , Poluentes Químicos da Água , Animais , Peixes , Metais , Poluentes Químicos da Água/toxicidade
18.
Cell Rep ; 37(6): 109975, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34758317

RESUMO

Dopamine (DA) neurons in the ventral tier of the substantia nigra pars compacta (SNc) degenerate prominently in Parkinson's disease, while those in the dorsal tier are relatively spared. Defining the molecular, functional, and developmental characteristics of each SNc tier is crucial to understand their distinct susceptibility. We demonstrate that Sox6 expression distinguishes ventrally and dorsally biased DA neuron populations in the SNc. The Sox6+ population in the ventral SNc includes an Aldh1a1+ subset and is enriched in gene pathways that underpin vulnerability. Sox6+ neurons project to the dorsal striatum and show activity correlated with acceleration. Sox6- neurons project to the medial, ventral, and caudal striatum and respond to rewards. Moreover, we show that this adult division is encoded early in development. Overall, our work demonstrates a dual origin of the SNc that results in DA neuron cohorts with distinct molecular profiles, projections, and functions.


Assuntos
Corpo Estriado/patologia , Neurônios Dopaminérgicos/patologia , Regulação da Expressão Gênica no Desenvolvimento , Doença de Parkinson/patologia , Fatores de Transcrição SOXD/metabolismo , Fatores de Transcrição SOXD/fisiologia , Substância Negra/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Corpo Estriado/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fatores de Transcrição SOXD/genética , Substância Negra/metabolismo , Área Tegmentar Ventral/metabolismo , Área Tegmentar Ventral/patologia
19.
Ann Transl Med ; 9(20): 1530, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34790736

RESUMO

BACKGROUND: B7 family molecules affect both immune responses and cancer progression via immunological and non-immunological pathways. However, the specific expression and prognostic value of B7 members in acute myeloid leukemia (AML) remains unclear; hence, an investigation using online bioinformatics databases is required. METHODS: In this study, we explored the expression of B7 molecules using the ONCOMINE, Gene Expression Profiling Interactive Analysis 2 (GEPIA2), and UALCAN databases, while the prognostic value of B7 molecules in AML was analyzed using the LinkedOmics, GEPIA2, UALCAN, and TCGAportal databases. Additionally, genetic alteration and gene co-expression analysis of the B7 family was performed via the cBioPortal and LinkedOmics databases, while functional and pathway enrichment analyses were conducted using the Metascape databases for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. RESULTS: The message RNA (mRNA) levels of B7 family members varied in AML patients, and aberrant highly expressed B7 members were correlated with poor prognosis in AML, including B7.1, B7-DC, B7-H3, B7-H5, and B7-H7. B7-H6 acted as a protective molecule for overall survival (OS), while B7-H1 overexpression was inclined to predict poor prognosis. B7 family gene alteration occurred frequently in AML, and the altered B7 group seemed to exhibit a trend towards worse OS. The co-expression genes and relative signaling pathways of the B7 family might be involved in oncogenesis and be associated with prognosis in AML. CONCLUSIONS: Our study showed that aberrantly expressed B7 family molecules affected the prognosis of AML patients, and thus, could be promising prognostic biomarkers and new therapeutic targets.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...