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1.
Chem Rev ; 122(6): 6850-6918, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35234464

RESUMO

Photoacoustic (PA) imaging technology, a three-dimensional hybrid imaging modality that integrates the advantage of optical and acoustic imaging, has great application prospects in molecular imaging due to its high imaging depth and resolution. To endow PA imaging with the ability for real-time molecular visualization and precise biomedical diagnosis, numerous activatable molecular PA probes which can specifically alter their PA intensities upon reacting with the targets or biological events of interest have been developed. This review highlights the recent developments of activatable PA probes for precise biomedical applications including molecular detection of the biotargets and imaging of the biological events. First, the generation mechanism of PA signals will be given, followed by a brief introduction to contrast agents used for PA probe design. Then we will particularly summarize the general design principles for the alteration of PA signals and activatable strategies for developing precise PA probes. Furthermore, we will give a detailed discussion of activatable PA probes in molecular detection and biomedical imaging applications in living systems. At last, the current challenges and outlooks of future PA probes will be discussed. We hope that this review will stimulate new ideas to explore the potentials of activatable PA probes for precise biomedical applications in the future.


Assuntos
Imagem Molecular , Técnicas Fotoacústicas , Imagem Molecular/métodos , Sondas Moleculares/química , Técnicas Fotoacústicas/métodos , Análise Espectral
2.
Ecotoxicol Environ Saf ; 279: 116470, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38772147

RESUMO

Several studies have suggested an association between exposure to various metals and the onset of type 2 diabetes (T2D). However, the results vary across different studies. We aimed to investigate the associations between serum metal concentrations and the risk of developing T2D among 8734 participants using a prospective cohort study design. We utilized inductively coupled plasmamass spectrometry (ICP-MS) to assess the serum concentrations of 27 metals. Cox regression was applied to calculate the hazard ratios (HRs) for the associations between serum metal concentrations on the risk of developing T2D. Additionally, 196 incident T2D cases and 208 healthy control participants were randomly selected for serum metabolite measurement using an untargeted metabolomics approach to evaluate the mediating role of serum metabolite in the relationship between serum metal concentrations and the risk of developing T2D with a nested casecontrol study design. In the cohort study, after Bonferroni correction, the serum concentrations of zinc (Zn), mercury (Hg), and thallium (Tl) were positively associated with the risk of developing T2D, whereas the serum concentrations of manganese (Mn), molybdenum (Mo), barium (Ba), lutetium (Lu), and lead (Pb) were negatively associated with the risk of developing T2D. After adding these eight metals, the predictive ability increased significantly compared with that of the traditional clinical model (AUC: 0.791 vs. 0.772, P=8.85×10-5). In the nested casecontrol study, a machine learning analysis revealed that the serum concentrations of 14 out of 1579 detected metabolites were associated with the risk of developing T2D. According to generalized linear regression models, 7 of these metabolites were significantly associated with the serum concentrations of the identified metals. The mediation analysis showed that two metabolites (2-methyl-1,2-dihydrophthalazin-1-one and mestranol) mediated 46.81% and 58.70%, respectively, of the association between the serum Pb concentration and the risk of developing T2D. Our study suggested that serum Mn, Zn, Mo, Ba, Lu, Hg, Tl, and Pb were associated with T2D risk. Two metabolites mediated the associations between the serum Pb concentration and the risk of developing T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Metais , Humanos , Diabetes Mellitus Tipo 2/sangue , Estudos Prospectivos , Masculino , Feminino , Pessoa de Meia-Idade , China , Metais/sangue , Adulto , Idoso , Poluentes Ambientais/sangue , Estudos de Coortes , Metabolômica , Estudos de Casos e Controles , Tálio/sangue , Exposição Ambiental/estatística & dados numéricos , População do Leste Asiático
3.
Sensors (Basel) ; 24(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38676276

RESUMO

Partial discharge detection is considered a crucial technique for evaluating insulation performance and identifying defect types in cable terminals of high-speed electric multiple units (EMUs). In this study, terminal samples exhibiting four typical defects were prepared from high-speed EMUs. A cable discharge testing system, utilizing high-frequency current sensing, was developed to collect discharge signals, and datasets corresponding to these defects were established. This study proposes the use of the convolutional neural network (CNN) for the classification of discharge signals associated with specific defects, comparing this method with two existing neural network (NN)-based classification models that employ the back-propagation NN and the radial basis function NN, respectively. The comparative results demonstrate that the CNN-based model excels in accurately identifying signals from various defect types in the cable terminals of high-speed EMUs, surpassing the two existing NN-based classification models.

4.
Molecules ; 29(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38257292

RESUMO

Inflammatory bowel disease (IBD) is a chronic and recurrent intestinal inflammatory disease, mainly including Crohn's disease (CD) and ulcerative colitis (UC). In recent years, the incidence and prevalence of IBD have been on the rise worldwide and have become a significant concern of health and a huge economic burden on patients. The occurrence and development of IBD involve a variety of pathogenic factors. The changes in short-chain fatty acids (SCFAs) are considered to be an important pathogenic mechanism of this disease. SCFAs are important metabolites in the intestinal microbial environment, which are closely involved in regulating immune, anti-tumor, and anti-inflammatory activities. Changes in metabolite levels can reflect the homeostasis of the intestinal microflora. Recent studies have shown that SCFAs provide energy for host cells and intestinal microflora, shape the intestinal environment, and regulate the immune system, thereby regulating intestinal physiology. SCFAs can effectively reduce the incidence of enteritis, cardiovascular disease, colon cancer, obesity, and diabetes, and also play an important role in maintaining the balance of energy metabolism (mainly glucose metabolism) and improving insulin tolerance. In recent years, many studies have shown that numerous decoctions and natural compounds of traditional Chinese medicine have shown promising therapeutic activities in multiple animal models of colitis and thus attracted increasing attention from scientists in the study of IBD treatment. Some of these traditional Chinese medicines or compounds can effectively alleviate colonic inflammation and clinical symptoms by regulating the generation of SCFAs. This study reviews the effects of various traditional Chinese medicines or bioactive substances on the production of SCFAs and their potential impacts on the severity of colonic inflammation. On this basis, we discussed the mechanism of SCFAs in regulating IBD-associated inflammation, as well as the related regulatory factors and signaling pathways. In addition, we provide our understanding of the limitations of current research and the prospects for future studies on the development of new IBD therapies by targeting SCFAs. This review may widen our understanding of the effect of traditional medicine from the view of SCFAs and their role in alleviating IBD animal models, thus contributing to the studies of IBD researchers.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Animais , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Medicina Tradicional , Medicina Tradicional Chinesa , Inflamação
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(2): 140-144, 2024 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-38311550

RESUMO

OBJECTIVE: To analyze the clinical and genetic characteristics of ten Chinese pedigrees affected with 7q11.23 duplication syndrome. METHODS: From December 2017 to January 2022, ten pedigrees diagnosed with 7q11.23 duplication syndrome at the First Affiliated Hospital of Zhengzhou University were enrolled as the study subjects. Clinical data of all subjects were collected, and some had subjected to copy number variation sequencing or single nucleotide polymorphism array to analyze the pattern of inheritance. RESULTS: The probands had included six fetuses and four adolescents. Four of the six prenatal cases showed abnormal ultrasound indicators, including three with soft indicators and one with abnormal fetal structural development. The clinical phenotype of the four adolescent cases had included mental retardation, delayed language development, and attention deficit hyperactivity disorder. The size of the copy number variations had ranged from 1.31 to 1.42 Mb, involving the classic region of 7q11.23 duplication syndrome. Of these, five cases had undergone parental origin testing, three cases were de novo, and two were hereditary. CONCLUSION: Individuals with 7q11.23 duplication syndrome may show substantial clinical phenotypic heterogeneity, hence the affected families should be provided with pre-pregnancy consultation and reproductive guidance.


Assuntos
Variações do Número de Cópias de DNA , Deficiência Intelectual , Gravidez , Feminino , Adolescente , Humanos , Linhagem , Deficiência Intelectual/genética , Síndrome , China
6.
J Am Chem Soc ; 145(9): 5134-5144, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36823697

RESUMO

Afterglow luminescence (long persistent luminescence) holds great potential for nonbackground molecular imaging. However, current afterglow probes are mainly nanoparticles, and afterglow imaging systems based on organic small molecules are still lacking and have rarely been reported. Moreover, the lack of reactive sites and a universal molecular scaffold makes it difficult to design activatable afterglow probes. To address these issues, this study reports a novel kind of hemicyanine-based molecule scaffolds with stimuli-responsive afterglow luminescence, which is dependent on an intramolecular cascade photoreaction between 1O2 and the afterglow molecule to store the photoenergy for delayed luminescence after light cessation. As a proof of concept, three modular activatable molecular afterglow probes (MAPs) with a "four-in-one" molecular design by integrating a stimuli-responsive unit, 1O2-generating unit, 1O2-capturing unit, and luminescent unit into one probe are customized for quantification and imaging of targets including pH, superoxide anions, and aminopeptidase. Notably, MAPs show higher sensitivity in afterglow imaging than in fluorescence imaging because the responsive unit simultaneously controls the initiation of fluorescence (S1 to S0) and 1O2 generation (S1 to T1). Finally, MAPs are applied for high-contrast afterglow imaging of drug-induced hepatotoxicity, which is poorly evaluated in clinics and drug discovery. By reporting the sequential occurrence of oxidative stress and upregulation of aminopeptidase, such activatable afterglow probes allow noninvasive imaging of hepatotoxicity earlier than the serological and histology manifestation, indicating their promise for early diagnosis of hepatotoxicity.


Assuntos
Luminescência , Nanopartículas , Nanopartículas/química , Imagem Molecular/métodos , Imagem Óptica
7.
Opt Express ; 31(23): 37381-37394, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017868

RESUMO

Thermo-optic phase shifters (TOPSs) are commonly used in large-scale silicon photonic integrated optical phased arrays (OPAs). However, fast-response TOPSs consume relatively high power; the elevated temperature floor in the dense region of the TOPSs introduces thermal crosstalk between optical paths, which undermines the control accuracy. We propose a combined method that involves subarray design in the optical power distribution network and array control method to predict, optimize, and redistribute the phase shifts and mitigates thermal crosstalk. Thermal simulations and an array control method for generic OPA models are discussed. A silicon photonic chip prototype of a 4 × 4 OPA with three-level cascaded subarrays is fabricated to demonstrate the proposed method. The experimental and statistical results show that the method effectively reduces the average total power consumption by 31%, the maximum local temperature by 18.4%, and the thermal crosstalk within the OPA.

8.
Aging Clin Exp Res ; 35(11): 2413-2423, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37707745

RESUMO

BACKGROUND: Frailty has been associated with a higher incidence of overall postoperative complications and mortality. However, the influence of frailty on the risk of venous thromboembolism (VTE) in patients with hip fracture following surgery remains unclear. We performed a meta-analysis to systematically evaluate the above association. METHODS: PubMed, Embase, Cochrane Library, Wanfang and CNKI were searched for relevant observational studies comparing the incidence of postoperative VTE in patients of hip fracture with and without frailty. Data collection, literature searching, and statistical analysis were conducted independently by two authors. Using a heterogeneity-incorporating random-effects model, the results were pooled. RESULTS: In this meta-analysis, 9509 patients from nine cohort studies were included. Pooled results showed that compared to those without frailty, patients with frailty at admission had a higher incidence of postoperative VTE (odds ratio [OR]: 2.59, 95% confidence interval [CI]: 1.25-5.39, p = 0.01; I2 = 66%). Subgroup analysis suggested the association between frailty and postoperative VTE was more remarkable in studies of patients with frailty prevalence < 50% (OR 6.28, 95% CI 3.31-11.90, p < 0.001; I2 = 8%) as compared to those ≥ 50% (OR 1.30, 95% CI 0.80-2.11, p = 0.28; I2 = 0%; p for subgroup difference < 0.001). Further meta-analyses showed that frailty at baseline was associated with a higher incidence of deep venous thrombosis (OR 3.15, 95% CI 1.33-7.47, p = 0.009; I2 = 59%), but not pulmonary embolism (OR 1.13, 95% CI 0.59-2.16, p = 0.72; I2 = 0%). CONCLUSION: Frailty is associated with a higher incidence of postoperative VTE in patients with hip fracture.


Assuntos
Fragilidade , Fraturas do Quadril , Embolia Pulmonar , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Anticoagulantes , Fragilidade/complicações , Embolia Pulmonar/complicações , Fraturas do Quadril/complicações , Fatores de Risco
9.
J Environ Manage ; 326(Pt A): 116675, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379078

RESUMO

Coastal zones are usually composed of coastlines and coastal wetlands and are among the most productive and dynamic ecosystems. However, the deltas are seldom detected and compared in detail at the continental scale to investigate the spatiotemporal evolution of coastline migration and coastal wetlands. Here we detected and compared the spatiotemporal changes in coastlines, wetlands, and ecosystem services in major deltas in Asia, including the Yellow River Delta (YRD), Yangtze River Delta (YAD), Pearl River Delta (PRD), Red River Delta (RRD), Mekong River Delta (MERD), Chao Phraya River Delta (CPRD), Mahanadi River Delta (MARD), Krishna River Delta (KRD), and Indus River Delta (IRD). We used time series remote sensing images from 1990 to 2019 to derive coastline and wetland information for the nine coastal zones. The ecosystem service value coefficients were applied to explore the ecosystem services characteristics of wetland changes in coastal areas. We found that the coastlines of the deltas in the study area changed less in the bedrock and sandy coasts, while the coastlines in the silty delta coasts changed more from 1990 to 2019. The interannual dynamics of coastal wetland areas in nine major deltas over the nearly 30 years can be divided into three periods: decreasing variability (1990-2005), increasing variability (2005-2015), and increasing volatility (2015-2019). Ecosystem services had an overall downward trend. These findings complement the official database of coastal planning and have substantial guiding implications for adjusting coastal management regulation policies.


Assuntos
Ecossistema , Áreas Alagadas , Rios , Ásia , China
10.
Environ Res ; 212(Pt B): 113297, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35436453

RESUMO

Meteorological factors have been confirmed to affect the COVID-19 transmission, but current studied conclusions varied greatly. The underlying causes of the variance remain unclear. Here, we proposed two scientific questions: (1) whether meteorological factors have a consistent influence on virus transmission after combining all the data from the studies; (2) whether the impact of meteorological factors on the COVID-19 transmission can be influenced by season, geospatial scale and latitude. We employed a meta-analysis to address these two questions using results from 2813 published articles. Our results showed that, the influence of meteorological factors on the newly-confirmed COVID-19 cases varied greatly among existing studies, and no consistent conclusion can be drawn. After grouping outbreak time into cold and warm seasons, we found daily maximum and daily minimum temperatures have significant positive influences on the newly-confirmed COVID-19 cases in cold season, while significant negative influences in warm season. After dividing the scope of the outbreak into national and urban scales, relative humidity significantly inhibited the COVID-19 transmission at the national scale, but no effect on the urban scale. The negative impact of relative humidity, and the positive impacts of maximum temperatures and wind speed on the newly-confirmed COVID-19 cases increased with latitude. The relationship of maximum and minimum temperatures with the newly-confirmed COVID-19 cases were more susceptible to season, while relative humidity's relationship was more affected by latitude and geospatial scale. Our results suggested that relationship between meteorological factors and the COVID-19 transmission can be affected by season, geospatial scale and latitude. A rise in temperature would promote virus transmission in cold seasons. We suggested that the formulation and implementation of epidemic prevention and control should mainly refer to studies at the urban scale. The control measures should be developed according to local meteorological properties for individual city.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Conceitos Meteorológicos , SARS-CoV-2 , Estações do Ano , Temperatura
11.
Anal Chem ; 93(16): 6463-6471, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33852265

RESUMO

Aminopeptidase N (APN) is capable of cleaving N-terminal amino acids from peptides with alanine in the N-terminal position and plays a key role in the growth, migration, and metastasis of cancer. However, reliable in situ information is hard to be obtained with the current APN-responsive molecular probes because the released fluorophores are cytoplasmic soluble and thus rapidly depart from the enzymatic reaction sites and spread out all over the cytoplasm. Here, we report a de novo precipitated fluorophore, HBPQ, which is completely insoluble in water and shows strong yellow solid emission when excited with a 405 nm laser. Owing to the controllable solid fluorescence of HBPQ by the protection-deprotection of phenolic hydroxyl, we further utilized HBPQ to design an APN-responsive fluorogenic probe (HBPQ-A) for the imaging of intracellular APN. Importantly, HBPQ-A can not only perform in situ imaging of APN in different organelles (e.g., lysosomes, mitochondria, endoplasmic reticula, and so forth) but also display a stable and indiffusible fluorescent signal for reliable mapping of the distribution of APN in living cells. In addition, through real-time imaging of APN in 4T1 tumors, we found that the fluorescent signal with high fidelity generated by HBPQ-A could remain constant even after 12 h, which further confirmed its diffusion-resistant ability and long-term reliable imaging ability. We believe that the precipitated fluorophore may have great potential for long-term in situ imaging.


Assuntos
Antígenos CD13 , Corantes Fluorescentes , Neoplasias , Fluorescência , Humanos , Sondas Moleculares , Neoplasias/diagnóstico por imagem
12.
J Transl Med ; 19(1): 125, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33766068

RESUMO

BACKGROUND: Multiple Sclerosis (MS) is a potentially devastating autoimmune neurological disorder, which characteristically induces demyelination of white matter in the brain and spinal cord. METHODS: In this study, three characteristics of the central nervous system (CNS) immune microenvironment occurring during MS onset were explored; immune cell proportion alteration, differential gene expression profile, and related pathways. The raw data of two independent datasets were obtained from the ArrayExpress database; E-MTAB-69, which was used as a derivation cohort, and E-MTAB-2374 which was used as a validation cohort. Differentially expressed genes (DEGs) were identified by the false discovery rate (FDR) value of < 0.05 and |log2 (Fold Change)|> 1, for further analysis. Then, functional enrichment analyses were performed to explore the pathways associated with MS onset. The gene expression profiles were analyzed using CIBERSORT to identify the immune type alterations involved in MS disease. RESULTS: After verification, the proportion of five types of immune cells (plasma cells, monocytes, macrophage M2, neutrophils and eosinophils) in cerebrospinal fluid (CSF) were revealed to be significantly altered in MS cases compared to the control group. Thus, the complement and coagulation cascades and the systemic lupus erythematosus (SLE) pathways may play critical roles in MS. We identified NLRP3, LILRB2, C1QB, CD86, C1QA, CSF1R, IL1B and TLR2 as eight core genes correlated with MS. CONCLUSIONS: Our study identified the change in the CNS immune microenvironment of MS cases by analysis of the in silico data using CIBERSORT. Our data may assist in providing directions for further research as to the molecular mechanisms of MS and provide future potential therapeutic targets in treatment.


Assuntos
Esclerose Múltipla , Encéfalo , Sistema Nervoso Central , Humanos , Medula Espinal , Transcriptoma/genética
13.
J Microsc ; 284(1): 74-82, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143441

RESUMO

Clear and complete microstructural imaging of the root canal isthmus is an important part of pathological investigations in research and clinical practice. X-ray micro-computed tomography (µCT) is a widely used non-destructive imaging technique, which allows for distortion-free three-dimensional (3D) visualisation. While absorption µCT typically has poor contrast resolution for observing the root canal isthmus, especially for weak-absorbing tissues, propagation-based X-ray phase-contrast imaging (PBI) is a powerful imaging method, which in its combination with µCT (PB-PCµCT) enables high-resolution and high-contrast microstructural imaging of the weak-absorbing tissues in samples. To investigate the feasibility and ability of PB-PCµCT in microstructural imaging of the root canal isthmus, conventional absorption µCT and PB-PCµCT experiments were performed. The two-dimensional (2D) and 3D comparison results demonstrated that, compared to absorption µCT, PB-PCµCT has the ability to image the root canal isthmus more clearly and completely, and thus, it has great potential to serve as a valuable tool for biomedical and preclinical studies on the root canal isthmus.


Assuntos
Cavidade Pulpar , Imageamento Tridimensional , Microscopia de Contraste de Fase , Microtomografia por Raio-X , Raios X
14.
Angew Chem Int Ed Engl ; 60(50): 26142-26150, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34554633

RESUMO

Nanozymes with intrinsic enzyme-like characteristics have attracted enormous research interest in biological application. However, there is a lack of facile approach for evaluating the catalytic activity of nanozymes in living system. Herein, we develop a novel manganese-semiconducting polymer-based nanozyme (MSPN) with oxidase-like activity for reporting the catalytic activity of itself in acid-induced cancer therapy via ratiometric near-infrared fluorescence (NIRF)-photoacoustic (PA) molecular imaging. Notably, MSPN possess oxidase-like activity in tumor microenvironment, owing to the mixed-valent MnOx nanoparticles, which can effectively kill cancer cells. Because the semiconducting polymer (PFODBT) is conjugated with oxidase-responsive molecule (ORM), the catalytic activity of nanozyme can be correlated with the ratiometric signals of NIRF (FL695 /FL825 ) and PA (PA680 /PA780 ), which may provide new ideas for predicting anticancer efficacy of nanozymes in living system.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Complexos de Coordenação/farmacologia , Manganês/farmacologia , Imagem Molecular , Polímeros/farmacologia , Animais , Antineoplásicos/química , Neoplasias da Mama/patologia , Catálise , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Concentração de Íons de Hidrogênio , Manganês/química , Camundongos , Técnicas Fotoacústicas , Polímeros/química , Semicondutores , Microambiente Tumoral/efeitos dos fármacos
15.
J Am Chem Soc ; 142(5): 2129-2133, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31955575

RESUMO

Labile heme (LH) is an important signaling molecule in virtually all organisms. However, specifically detecting LH remains an outstanding challenge. Herein, by learning from the bioactivation mechanism of artemisinin, we have developed the first LH-responsive small-molecule fluorescent probe, HNG, based on a 4-amino-1,8-naphthalimide (NG) fluorophore. HNG showed high selectivity for LH without interference from hemin, protein-interacting heme, and zinc protoporphyrin. Using HNG, the changes of LH levels in live cells were imaged, and a positive correlation of LH level with the degree of hemolysis was uncovered in hemolytic mice. Our study not only presents the first molecular probe for specific LH detection but also provides a strategy to construct probes with high specificity through a bioinspired approach.


Assuntos
Artemisininas/farmacologia , Corantes Fluorescentes/química , Heme/química , Lactonas/farmacologia , Animais , Artemisininas/química , Humanos , Lactonas/química , Camundongos , Transdução de Sinais
16.
Arch Toxicol ; 94(4): 1279-1302, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32303808

RESUMO

In the present study, the neurotoxicity and mechanisms of di-(2-ethylhexyl) phthalate (DEHP) exposure on pubertal normal (P-normal) and pubertal type 2 diabetes mellitus (P-T2DM) mice were investigated by typical neurobehavioral methods and transcriptome analysis. Pubertal male ICR mice were orally exposed to DEHP (0.18, 1.8, 18 and 180 mg/kg/d) for 3 weeks. In Open field test, DEHP significantly increased the time in central area staying and decreased the total distance and clockwise (CW) rotation of P-normal and P-T2DM mice. Morris water maze showed that DEHP significantly increased the latency in locating platform and decreased the original platform quadrant and residence time in target quadrant of P-normal and P-T2DM mice. Transcriptome analysis results revealed the effects of DEHP exposure on neural signaling pathway including biogenic amines neurotransmitters, nerve receptors, neurobiological processes, etc. Enzyme-linked immunosorbent assay (ELISA) and western blotting results showed that DEHP significantly decreased the contents of 5-HT, cAMP, GABA and Ca2+, the levels of CREB, phosphorylation of PKA, ERK1/2 and CREB, increased the levels of CaM and phosphorylation of CaMKII in P-normal and P-T2DM mice. Factorial analysis results showed that P-T2DM mice were more sensitive than those of P-normal mice. The potential neurotoxicity mechanism of DEHP may be synergistically mediated by the cAMP-PKA-ERK1/2-CREB signaling and the Ca2+ signaling pathway.


Assuntos
Dietilexilftalato/toxicidade , Disruptores Endócrinos/toxicidade , Sistema Nervoso/efeitos dos fármacos , Animais , Diabetes Mellitus Tipo 2 , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos ICR , Sistema Nervoso/metabolismo , Síndromes Neurotóxicas , Ácidos Ftálicos
17.
Sensors (Basel) ; 20(19)2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998319

RESUMO

The successful launch of the Sentinel-2 constellation satellite, along with advanced cloud detection algorithms, has enabled the generation of continuous time series at high spatial and temporal resolutions, which is in turn expected to enable the classification of salt marsh vegetation over larger spatiotemporal scales. This study presents a critical comparison of vegetation index (VI) and curve fitting methods-two key factors for time series construction that potentially influence vegetation classification performance. To accomplish this objective, the stability of five different VI time series, namely Normalized Difference Vegetation Index (NDVI), Soil-Adjusted Vegetation Index (SAVI), Enhanced Vegetation Index (EVI), Green Normalized Difference Vegetation Index (GNDVI), and Water-Adjusted Vegetation Index (WAVI), was compared empirically; the suitability between three curve fitting methods, namely Asymmetric Gaussian (AG), Double Logistic (DL), and Two-term Fourier (TF), and VI time series was measured using the coefficient of determination, and the salt marsh vegetation separability among different combinations of VI time series and curve fitting methods (i.e., VI time series-based curve fitting model) was quantified using overall the Jeffries-Matusita distance. Six common types of salt marsh vegetation from three typical coastal sites in China were used to validate these findings, which demonstrate: (1) the SAVI performed best in terms of time series stability, while the EVI exhibited relatively poor time series stability with conspicuous outliers induced by the sensitivity to omitted clouds and shadows; (2) the DL method commonly resulted in the most accurate classification of different salt marsh vegetation types, especially when combined with the EVI time series, followed by the TF method; and (3) the SAVI/NDVI-based DL/TF model demonstrated comparable efficiency for classifying salt marsh vegetation. Notably, the SAVI/NDVI-based DL model performed most strongly for high latitude regions with a continental climate, whilst the SAVI/NDVI-based TF model appears to be better suited to mid- to low latitude regions dominated by a monsoonal climate.

18.
J Am Chem Soc ; 141(34): 13572-13581, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31370392

RESUMO

Cancer treatments are confounded by severe toxic effects toward patients. To address these issues, activatable nanoprobes have been designed for specific imaging and destruction of cancer cells under the stimulation of specific cancer-associated biomarkers. Most activatable nanoprobes were usually activated by some single-factor stimulation, but this restricts therapeutic specificity between diseased and normal tissue; therefore, multifactor activation is highly desired. To this end, we herein develop a novel dual-stimuli responsive theranostic nanoprobe for simultaneously activatable cancer imaging and photothermal therapy under the coactivation of "dual-key" stimulation of "nitric oxide (NO)/acidity", so as to further improve the therapeutic specificity. Specifically, we have integrated a weak electron acceptor (benzo[c][1,2,5]thiadiazole-5,6-diamine) into a donor-π-acceptor-π-donor type chromophore. When the weak acceptor was oxidized by NO in acidic conditions to form a stronger acceptor (5H-[1,2,3]triazolo[4,5-f]-2,1,3-benzothiadiazole), the molecule absorption was significantly increased in the near-infrared region, based on the intramolecular charge transfer (ICT) mechanism. Under the dual-key stimulation of NO/acidity within the tumor associated with inflammation, the nanoprobe can correspondingly output dual signals for ratiometric photoacoustic and photothermal imaging of cancer in vivo and do so with enhanced accuracy and specificity. Our novel nanoprobe exhibited higher photoacoustic signal enhancement under dual-factor activation at 9.8 times that of NO and 132 times that of acidity alone, respectively. Moreover, through such dual activation of NO/acidity, the nanoprobe produces more differentiation of hyperthermia between tumor and normal tissues, to afford satisfactory photothermal therapy with minimal toxic side effects. Thus, our work presents a promising strategy for significantly improving the precision and specificity of cancer imaging and therapy.


Assuntos
Nanopartículas/uso terapêutico , Neoplasias/terapia , Óxido Nítrico/metabolismo , Tiadiazóis/uso terapêutico , Animais , Linhagem Celular Tumoral , Feminino , Células HeLa , Humanos , Hipertermia Induzida , Camundongos , Imagem Molecular , Nanopartículas/química , Neoplasias/metabolismo , Neoplasias/patologia , Imagem Óptica , Técnicas Fotoacústicas , Fototerapia , Nanomedicina Teranóstica , Tiadiazóis/química
19.
Arch Toxicol ; 93(11): 3183-3206, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31606821

RESUMO

The prevalence of adolescent type 2 diabetes mellitus (A-T2DM) is increasing year by year. Di-(2-ethylhexyl)phthalate (DEHP), a widely used plasticizer, could exacerbate type 2 diabetes mellitus (T2DM). The study aimed to investigate the metabolic toxicity, susceptibility and mechanism of DEHP exposure to A-T2DM. DEHP was administered orally (0, 0.18, 1.8, 18, and 180 mg/kg/day) for 3 weeks to adolescent normal mice (A-normal mice) and established A-T2DM mice. The results of fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) levels showed that the susceptibility of A-T2DM mice to DEHP exposure was more significant than that of A-normal mice. DEHP, interfering with glucose and lipid metabolism of A-normal and A-T2DM mice, caused the body weight increase of A-normal mice and decrease of A-T2DM mice. Besides, DEHP could cause more injury of cardiovascular, hepatic and renal function to A-T2DM mice than A-normal mice. Hepatic transcriptome analysis revealed that DEHP exposure interfered with the biological feedback adjustment of endocrine and metabolic system in A-T2DM mice and then led to the development of T2DM. According to the transcriptome results, insulin signaling transduction pathway was applied and researched by immunoassay. It was discovered that DEHP reduced insulin sensitivity and disturbed insulin signaling transduction, glucose utilization, lipid synthesis and protein synthesis. Collectively, DEHP could disturb the endocrine and metabolic functions and increase the insulin resistance in adolescent mice. Moreover, the adolescent T2DM mice are more sensitive to DEHP-induced endocrine and metabolic toxicity than the healthy adolescent mice.


Assuntos
Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Tipo 2/induzido quimicamente , Dietilexilftalato/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Plastificantes/toxicidade , Transcriptoma/efeitos dos fármacos , Animais , Glicemia/análise , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Glucose/metabolismo , Resistência à Insulina/genética , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos ICR
20.
Biochem Biophys Res Commun ; 506(3): 703-708, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30376989

RESUMO

Alternative splicing of exon 6 in Fas pre-mRNA generates a membrane bound pro-apoptotic isoform or soluble anti-apoptotic isoform. SRSF4 is a member of Arginine-Serine rich (SR) protein family. Here we demonstrate that increased SRSF4 expression stimulates exon 6 inclusion, and that reduced SRSF4 expression promotes exon 6 exclusion. We also show that weaker but not stronger 5' splice-site strength of exon 6 abolishes the SRSF4 effects on exon 6 splicing. Furthermore, we identified a novel enhancer on exon 6, on which SRSF4 interacts functionally and physically. Our results illustrate a novel regulatory mechanism of Fas pre-mRNA splicing.


Assuntos
Elementos Facilitadores Genéticos/genética , Éxons/genética , Precursores de RNA/metabolismo , Splicing de RNA/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Receptor fas/genética , Sequência de Bases , Regulação da Expressão Gênica , Células HCT116 , Humanos , Ligação Proteica/genética , Precursores de RNA/genética , Sítios de Splice de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor fas/metabolismo
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