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1.
J Comput Assist Tomogr ; 48(3): 491-497, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38157266

RESUMO

OBJECTIVE: Salivary gland lesions show overlapping morphological findings and types of time/intensity curves. This research aimed to evaluate the role of 2-phase multislice spiral computed tomography (MSCT) texture analysis in differentiating between benign and malignant salivary gland lesions. METHODS: In this prospective study, MSCT was carried out on 90 patients. Each lesion was segmented on axial computed tomography (CT) images manually, and 33 texture features and morphological CT features were assessed. Logistic regression analysis was used to confirm predictors of malignancy ( P < 0.05 was considered to be statistically significant), followed by receiver operating characteristics analysis to assess the diagnostic performance. RESULTS: Univariate logistic regression analysis revealed that morphological CT features (shape, size, and invasion of adjacent tissues) and 17 CT texture parameters had significant differences between benign and malignant lesions ( P < 0.05). Multivariate binary logistic regression demonstrated that shape, invasion of adjacent tissues, entropy, and inverse difference moment were independent factors for malignant tumors. The diagnostic accuracy values of multivariate binary logistic models based on morphological parameters, CT texture features, and a combination of both were 87.8%, 90%, and 93.3%, respectively. CONCLUSIONS: Two-phase MSCT texture analysis was conducive to differentiating between malignant and benign neoplasms in the salivary gland, especially when combined with morphological CT features.


Assuntos
Neoplasias das Glândulas Salivares , Humanos , Feminino , Masculino , Neoplasias das Glândulas Salivares/diagnóstico por imagem , Neoplasias das Glândulas Salivares/patologia , Pessoa de Meia-Idade , Diagnóstico Diferencial , Adulto , Idoso , Estudos Prospectivos , Adulto Jovem , Adolescente , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Idoso de 80 Anos ou mais , Reprodutibilidade dos Testes , Tomografia Computadorizada Multidetectores/métodos , Tomografia Computadorizada Espiral/métodos , Glândulas Salivares/diagnóstico por imagem
2.
J Neurosci Res ; 101(6): 930-951, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36720002

RESUMO

Interleukin-1ß (IL-1ß) has been described to exert important effect on synapses in the brain. Here, we explored if the synapses in the hippocampus would be adversely affected following intracerebral IL-1ß injection and, if so, to clarify the underlying molecular mechanisms. Adult male Sprague-Dawley rats were divided into control, IL-1ß, IL-1ß + PD98059, and IL-1ß + MG132 groups and then sacrificed for detection of synaptophysin (syn) protein level, synaptosome glutamate release, and synapse ultrastructure by western blotting, glutamate kit and electron microscopy, respectively. These rats were tested by Morris water maze for learning and memory ability. It was determined by western blotting whether IL-1ß exerted the effect of on syn and siah1 expression in primary neurons via extracellular regulated protein kinases (ERK) signaling pathway. Intrahippocampal injection of IL-1ß in male rats and sacrificed at 8d resulted in a significant decrease in syn protein, damage of synapse structure, and abnormal release of neurotransmitters glutamate. ERK inhibitor and proteosome inhibitor treatment reversed the above changes induced by IL-1ß both in vivo and in vitro. In primary cultured neurons incubated with IL-1ß, the expression level of synaptophysin was significantly downregulated coupled with abnormal glutamate release. Furthermore, use of PD98059 had confirmed that ERK signaling pathway was implicated in synaptic disorders caused by IL-1ß treatment. The present results suggest that exogenous IL-1ß can suppress syn protein level and glutamate release. A possible mechanism for this is that IL-1ß induces syn degradation that is regulated by the E3 ligase siah1 via the ERK signaling pathway.


Assuntos
Proteínas Quinases , Transdução de Sinais , Animais , Masculino , Ratos , Glutamatos , Interleucina-1beta/metabolismo , Proteínas Quinases/metabolismo , Ratos Sprague-Dawley , Sinaptofisina/metabolismo
3.
Cell Mol Neurobiol ; 43(7): 3669-3692, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37479855

RESUMO

Neuroinflammation is a common characteristic of intracranial infection (ICI), which is associated with the activation of astrocytes and microglia. MiRNAs are involved in the process of neuroinflammation. This study aimed to investigate the potential mechanism by which miR-338-3p negatively modulate the occurrence of neuroinflammation. We here reported that the decreased levels of miR-338-3p were detected using qRT-PCR and the upregulated expression of TNF-α and IL-1ß was measured by ELISA in the cerebrospinal fluid (CSF) in patients with ICI. A negative association between miR-338-3p and TNF-α or IL-1ß was revealed by Pearson correlation analysis. Sprague-Dawley (SD) rats were injected with LPS (50 µg) into left cerebral ventricule (LCV), following which the increased expression of TNF-α and IL-1ß and the reduction of miR-338-3p expression were observed in the corpus callosum (CC). Moreover, the expression of TNF-α and IL-1ß in the astrocytes and microglia in the CC of LCV-LPS rats were saliently inhibited by the overexpression of miR-338-3p. In vitro, cultured astrocytes and BV2 cells transfected with mimic-miR-338-3p produced less TNF-α and IL-1ß after LPS administration. Direct interaction between miR-338-3p and STAT1 mRNA was validated by biological information analysis and dual luciferase assay. Furthermore, STAT1 pathway was found to be implicated in inhibition of neuroinflammation induced by mimic miR-338-3p in the astrocytes and BV2 cells. Taken together, our results suggest that miR-338-3p suppress the generation of proinflammatory mediators in astrocyte and BV2 cells induced by LPS exposure through the STAT1 signal pathway. MiR-338-3p could act as a potential therapeutic strategy to reduce the neuroinflammatory response. Diagram describing the cellular and molecular mechanisms associated with LPS-induced neuroinflammation via the miR-338-3p/STAT1 pathway. LPS binds to TLRs on astrocytes or microglia to activate the STAT1 pathway and upregulate the production of pro-inflammatory cytokines. However, miR-338-3p inhibits the expression of STAT1 and reduces the production of inflammatory mediators.


Assuntos
MicroRNAs , Doenças Neuroinflamatórias , Ratos , Animais , Ratos Sprague-Dawley , Corpo Caloso , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa , MicroRNAs/genética , Transdução de Sinais
4.
BMC Infect Dis ; 20(1): 899, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256643

RESUMO

BACKGROUND: COVID-19 has become a major global threat. The present study aimed to develop a nomogram model to predict the survival of COVID-19 patients based on their clinical and laboratory data at admission. METHODS: COVID-19 patients who were admitted at Hankou Hospital and Huoshenshan Hospital in Wuhan, China from January 12, 2020 to March 20, 2020, whose outcome during the hospitalization was known, were retrospectively reviewed. The categorical variables were compared using Pearson's χ2-test or Fisher's exact test, and continuous variables were analyzed using Student's t-test or Mann Whitney U-test, as appropriate. Then, variables with a P-value of ≤0.1 were included in the log-binomial model, and merely these independent risk factors were used to establish the nomogram model. The discrimination of the nomogram was evaluated using the area under the receiver operating characteristic curve (AUC), and internally verified using the Bootstrap method. RESULTS: A total of 262 patients (134 surviving and 128 non-surviving patients) were included in the analysis. Seven variables, which included age (relative risk [RR]: 0.905, 95% confidence interval [CI]: 0.868-0.944; P < 0.001), chronic heart disease (CHD, RR: 0.045, 95% CI: 0.0097-0.205; P < 0.001, the percentage of lymphocytes (Lym%, RR: 1.125, 95% CI: 1.041-1.216; P = 0.0029), platelets (RR: 1.008, 95% CI: 1.003-1.012; P = 0.001), C-reaction protein (RR: 0.982, 95% CI: 0.973-0.991; P < 0.001), lactate dehydrogenase (LDH, RR: 0.993, 95% CI: 0.990-0.997; P < 0.001) and D-dimer (RR: 0.734, 95% CI: 0.617-0.879; P < 0.001), were identified as the independent risk factors. The nomogram model based on these factors exhibited a good discrimination, with an AUC of 0.948 (95% CI: 0.923-0.973). CONCLUSIONS: A nomogram based on age, CHD, Lym%, platelets, C-reaction protein, LDH and D-dimer was established to accurately predict the prognosis of COVID-19 patients. This can be used as an alerting tool for clinicians to take early intervention measures, when necessary.


Assuntos
COVID-19/epidemiologia , COVID-19/mortalidade , Cardiopatias/epidemiologia , Nomogramas , Pandemias , Admissão do Paciente , SARS-CoV-2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , COVID-19/sangue , COVID-19/virologia , China/epidemiologia , Doença Crônica/epidemiologia , Comorbidade , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Linfócitos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Taxa de Sobrevida
5.
BMC Med Imaging ; 20(1): 117, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066760

RESUMO

BACKGROUND: To investigate whether quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) pharmacokinetic parameters can be used to predict the pathologic stages of oral tongue squamous cell carcinoma (OTSCC). METHODS: For this prospective study, DCE-MRI was performed in participants with OTSCC from May 2016 to June 2017. The pharmacokinetic parameters, including Ktrans, Kep, Ve, and Vp, were derived from DCE-MRI by utilizing a two-compartment extended Tofts model and a three-dimensional volume of interest. The postoperative pathologic stage was determined in each patient based on the 8th AJCC cancer staging manual. The quantitative DCE-MRI parameters were compared between stage I-II and stage III-IV lesions. Logistic regression analysis was used to determine independent predictors of tumor stages, followed by receiver operating characteristic (ROC) analysis to evaluate the predictive performance. RESULTS: The mean Ktrans, Kep and Vp values were significantly lower in stage III-IV lesions compared with stage I-II lesions (p = 0.013, 0.005 and 0.011, respectively). Kep was an independent predictor for the advanced stages as determined by univariate and multivariate logistic analysis. ROC analysis showed that Kep had the highest predictive capability, with a sensitivity of 64.3%, a specificity of 82.6%, a positive predictive value of 81.8%, a negative predictive value of 65.5%, and an accuracy of 72.5%. CONCLUSION: The quantitative DCE-MRI parameter Kep can be used as a biomarker for predicting pathologic stages of OTSCC.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias da Língua/diagnóstico por imagem , Neoplasias da Língua/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/cirurgia , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Interpretação de Imagem Radiográfica Assistida por Computador , Neoplasias da Língua/cirurgia , Adulto Jovem
6.
Angew Chem Int Ed Engl ; 58(5): 1463-1467, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30536782

RESUMO

Herein, an amino-acid-boosted biomimetic strategy is reported that enabled the rapid encapsulation, or co-encapsulation, of a broad range of proteins into microporous metal-organic frameworks (MOFs), with an ultrahigh loading efficiency. It relies on the accelerated formation of prenucleation clusters around proteins via a metallothionein-like self-assembly. The encapsulated proteins maintained their native conformations, and the structural confinement within porous MOFs endowed enzymes with excellent bioactivity, even in harsh conditions (e.g. in the presence of proteolytic or chemical agents or at high temperature). Furthermore, owing to the merits of nondestructive and protein surface charge-independent encapsulation, the feasibility of this biomimetic strategy for biostorage, enzyme cascades, and biosensing was also verified. It is believed that this convenient and versatile encapsulation strategy has great promise in the important fields of biomedicine, catalysis, and biosensing.


Assuntos
Aminoácidos/química , Materiais Biomiméticos/química , Estruturas Metalorgânicas/química , Substâncias Macromoleculares/química
7.
Cell Physiol Biochem ; 49(5): 1755-1765, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30231239

RESUMO

BACKGROUND/AIMS: Increasing evidence has shown that miR-216b plays an important role in human cancer progression. However, little is known about the function of miR-216b in renal cell carcinoma. METHODS: The expression levels of miR-216b in renal cell carcinoma tissues and cell lines were examined by qRT-PCR. The biological role of miR-216b in renal cell carcinoma proliferation and/or metastasis was examined in vitro and in vivo. The target of miR-216b was identified by a dual-luciferase reporter assay. The expression level of KRAS protein was measured by western blotting. RESULTS: The expression of miR-216b was downregulated in clear cell renal cell carcinoma (ccRCC) cell lines and specimens compared to the adjacent normal tissues. Furthermore, miR-216b can bind to the 3'untranslated region (UTR) of KRAS and inhibit the expression of KRAS through translational repression. The in vitro study revealed that miR-216b attenuated ccRCC cell proliferation and invasion. Furthermore, in vivo study also showed that miR-216b suppressed tumor growth. MiR-216b exerted its tumor suppressor function through inhibiting the KRAS-related MAPK/ERK and PI3K/AKT pathways. CONCLUSION: Our findings provide, for the first time, significant clues regarding the role of miR-216b as a tumor suppressor by targeting KRAS in ccRCC.


Assuntos
Carcinoma de Células Renais/fisiopatologia , Regulação para Baixo , Neoplasias Renais/fisiopatologia , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Regiões 3' não Traduzidas , Animais , Antagomirs/metabolismo , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/uso terapêutico , Transdução de Sinais
8.
J Environ Sci (China) ; 65: 282-292, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29548399

RESUMO

Hexagonal turbostratic birnessite, with the characteristics of high contents of vacancies, varying amounts of structural and adsorbed Mn3+, and small particle size, undergoes strong adsorption reactions with trace metal (TM) contaminants. While the interactions of TM, i.e., Zn2+, with birnessite are well understood, the effect of birnessite structural characteristics on the coordination and stability of Zn2+ on the mineral surfaces under proton attack is as yet unclear. In the present study, the effects of a series of synthesized hexagonal turbostratic birnessites with different Mn average oxide states (AOSs) on the coordination geometry of adsorbed Zn2+ and its stability under acidic conditions were investigated. With decreasing Mn AOS, birnessite exhibits smaller particle sizes and thus larger specific surface area, higher amounts of layer Mn3+ and thus longer distances for the first MnO and MnMn shells, but a low quantity of available vacancies and thus low adsorption capacity for Zn2+. Zn K-edge EXAFS spectroscopy demonstrates that birnessite with low Mn AOS has smaller adsorption capacity but more tetrahedral Zn (IVZn) complexes on vacancies than octahedral (VIZn) complexes, and Zn2+ is more unstable under acidic conditions than that adsorbed on birnessite with high Mn AOS. High Zn2+ loading favors the formation of VIZn complexes over IVZn complexes, and the release of Zn2+ is faster than at low loading. These results will deepen our understanding of the interaction mechanisms of various TMs with natural birnessites, and the stability and thus the potential toxicity of heavy metal pollutants sequestered by engineered nano-sized metal oxide materials.


Assuntos
Poluentes Ambientais/química , Manganês/química , Modelos Químicos , Óxidos/química , Zinco/química , Manganês/classificação , Oxirredução
9.
J Hazard Mater ; 465: 133107, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38043424

RESUMO

Though both iron (hydr)oxides and soil organic matter (SOM) significantly influence heavy metal behaviors in soils, studies on the characteristics of natural minerals and the synergic effects of the two on Cr(VI) transformation are limited. This study investigated Cr(VI) retention mechanisms in four soils from tropical and subtropical regions of China based on a comprehensive characterization of Fe (hydr)oxides. These soils exhibited varying quantities of hematite, ferrihydrite and goethite, with distinct Al substitution levels and varied exposed crystallographic facets. Adsorption experiments revealed a positive correlation between Fe (hydr)oxide content and Cr(VI) fixation amount on colloid, which was influenced by the mineral types, Al substitution levels and facet exposures. Further, Cr(VI) was sequestered on soil by adsorption and reduction. In soils enriched with crystalline Fe (hydr)oxides, Cr(VI) reduction was primarily governed by SOM, while in soils enriched with poorly crystalline Fe (hydr)oxides, mineral-associated Fe(II) also contributed to Cr(VI) reduction. Aging experiments demonstrated that SOM and mineral-associated Fe(II) expedited Cr (VI) passivation and diminished the Cr leaching. These results improve our understanding of natural Fe (hydr)oxide structures and their impact on Cr(VI) behavior in soils, and shed light on complex soil-contaminant interactions and remediation of Cr(VI) polluted soils.

10.
Aquat Toxicol ; 273: 106999, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38875954

RESUMO

The coexistence of multiple emerging contaminants imposes a substantial burden on the ecophysiological functions in organisms. The combined toxicity and underlying mechanism requires in-depth understanding. Here, marine blue mussel (Mytilus galloprovincialis L.) was selected and exposed to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and perfluorooctanoic acid (PFOA) individually and in combination at environmental related concentrations to elucidate differences in stress responses and potential toxicological mechanisms. Characterization and comparison of accumulation, biomarkers, histopathology, transcriptomics and metabolomics were performed. Co-exposure resulted in differential accumulation patterns, exacerbated histopathological alterations, and different responses in oxidative stress and biomarkers for xenobiotic transportation. Moreover, the identified differentially expressed genes (DEGs) and differential metabolites (DEMs) in mussels were found to be annotated to different metabolic pathways. Correlation analyses further indicated that DEGs and DEMs were significantly correlated with the above biomarkers. BDE-47 and PFOA altered the genes and metabolites related to amino acid metabolism, energy and purine metabolism, ABC transporters, and glutathione metabolism to varying degrees, subsequently inducing accumulation differences and combined toxicity. Furthermore, the present work highlighted the pivotal role of Nrf2-keap1 detoxification pathway in the acclimation of M. galloprovincialis to reactive oxygen species (ROS) stress induced by BDE-47 and PFOA. This study enabled more comprehensive understanding of combined toxic mechanism of multi emerging contaminants pollution.

11.
Front Neurosci ; 17: 1160853, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37564367

RESUMO

Purpose: This study was conducted to reexamine the question of whether children treated for anisometropic amblyopia have contour integration deficits. To do so, we used psychophysical methods that require global contour processing while minimizing the influence of low-level deficits: visibility, shape perception, and positional uncertainty. Methods: Thirteen children with anisometropic amblyopia (age: 10.1 ± 1.8 years) and thirteen visually normal children (age: 10.8 ± 2.0 years) participated in this study. The stimuli were closed figures made up of Gabor patches either in noise or on a blank field. The contrast thresholds to detect a circular contour on a blank field, as well as the thresholds of aspect ratio and contour element number to discriminate a circular or elliptical contour in noise, were measured at Gabor spatial frequencies of 1.5, 3, and 6 cpd for amblyopic eyes (AEs), fellow eyes (FEs), and normal control eyes. Visual acuities and contrast sensitivity functions for AEs and FEs and the Randot stereoacuity were measured before testing. Results: The AEs showed contrast deficits and degraded shape perception compared to the FEs at higher spatial frequencies (6 cpd). When the influence of abnormal contrast sensitivity and shape perception were minimized, the AEs showed contour integration deficits at spatial frequencies 3 and 6 cpd. These deficits were not related to basic losses in contrast sensitivity and acuity, stereoacuity, and visual crowding. Besides, no significant difference was found between the fellow eyes of the amblyopic children and the normal control eyes in the performance of contour integration. Conclusion: After eliminating or compensating for the low-level deficits, children treated for anisometropic amblyopia still show contour integration deficits, primarily at higher spatial frequencies, which might reflect the deficits in global processing caused by amblyopia. Contour integration deficits are likely independent of spatial vision deficits. Refractive correction and/or occlusion therapies may not be sufficient to fully restore contour integration deficits, which indicates the need for the development of clinical treatments to recover these deficits.

12.
Front Immunol ; 14: 1225482, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38115999

RESUMO

Background: Neuroinflammation is a common feature of many neurological diseases, and remains crucial for disease progression and prognosis. Activation of microglia and astrocytes can lead to neuroinflammation. However, little is known about the role of lncRNA xist and miR-122-5p in the pathogenesis of sepsis-associated neuroinflammation (SAN). This study aims to investigate the role of lncRNA xist and miR-122-5p in the pathogenesis of SAN. Methods: Levels of miR-122-5p and proinflammatory mediators were detected in the cerebrospinal fluid (CSF) of patients with intracranial infection (ICI) by ELISA and qRT-PCR. miRNA expression in the periventricular white matter (PWM) in rats was analyzed by high-throughput sequencing. Levels of lncRNA xist, miR-122-5p and proinflammatory mediators in the PWM were measured using qRT-PCR and western blot. Bioinformatics analysis was used to predict the upstream and downstream of miR-122-5p. The interaction between miR-122-5p and its target protein was validated using luciferase reporter assay. BV2 and astrocytes were used to detect the expression of lncRNA xist, miR-122-5p. Results: The level of miR-122-5p was significantly decreased in the CSF of ICI patients, while the expression of IL-1ß and TNF-α were significantly upregulated. Furthermore, it was found that the expression of IL-1ß and TNF-α were negatively correlated with the level of miR-122-5p. A high-throughput sequencing analysis showed that miR-122-5p expression was downregulated with 1.5-fold changes in the PWM of CLP rats compared with sham group. Bioinformatics analysis found that lncRNA xist and PKCη were the upstream and downstream target genes of miR-122-5p, respectively. The identified lncRNA xist and PKCη were significantly increased in the PWM of CLP rats. Overexpression of miR-122-5p or knockdown of lncRNA xist could significantly downregulate the level of PKCη and proinflammatory mediators from activated microglia and astrocytes. Meanwhile, in vitro investigation showed that silencing lncRNA xist or PKCη or enhancing the expression of miR-122-5p could obviously inhibit the release of proinflammatory mediators in activated BV2 cells and astrocytes. Conclusion: LncRNA xist could regulate microglia and astrocytes activation in the PWM of CLP rats via miR-122-5p/PKCη axis, further mediating sepsis associated neuroinflammation.


Assuntos
MicroRNAs , RNA Longo não Codificante , Sepse , Substância Branca , Animais , Humanos , Ratos , MicroRNAs/genética , MicroRNAs/metabolismo , Doenças Neuroinflamatórias , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Sepse/complicações , Sepse/genética , Fator de Necrose Tumoral alfa/metabolismo , Substância Branca/metabolismo
13.
Small Methods ; 6(7): e2101531, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35587180

RESUMO

Chemotherapy plays an important role in treating cancers in clinic. Hypoxia-mediated chemoresistance remains a major hurdle for effective tumor chemotherapy. Herein, a new class of tLyP-1-modified dopamine (DOPA)-ß-cyclodextrin (CD)-coated paclitaxel (PTX)- and manganese dioxide (MnO2 )-loaded nanoparticles (tLyP-1-CD-DOPA-MnO2 @PTX) is developed to enhance glioma chemotherapy. The nanomedicine delivered to the tumor site decomposes in response to the weak acidity and high hydrogen peroxide in the tumor microenvironment (TME), resulting in collapse of the system to release PTX and generates Mn2+ and O2 . In a rat model of intracranial glioma, tLyP-1-CD-DOPA-MnO2 @PTX can efficiently pass through the blood-brain-barrier to accumulate in tumor sites. The hypoxia in TME can be relieved via O2 generated by MnO2 and the reactive oxygen species produced by Mn2+ can kill tumor cells. The tLyP-1-CD-DOPA-MnO2 @PTX nanoparticles exert a remarkable antitumor effect by promoting apoptosis and inhibiting proliferation of tumor cells in addition to enabling real-time tumor monitoring with magnetic resonance imaging. This MnO2 -based theranostic medicine will offer a novel strategy to simultaneously enhance chemotherapy and achieve real-time imaging of therapeutic process in glioma treatment.


Assuntos
Glioma , Compostos de Manganês , Animais , Di-Hidroxifenilalanina/uso terapêutico , Glioma/tratamento farmacológico , Hipóxia/tratamento farmacológico , Compostos de Manganês/farmacologia , Óxidos/farmacologia , Paclitaxel/uso terapêutico , Ratos , Microambiente Tumoral
14.
Mol Neurobiol ; 58(12): 6552-6576, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34585328

RESUMO

Microglia activation and associated inflammation are implicated in the periventricular white matter damage (PWMD) in septic postnatal rats. This study investigated whether melatonin would mitigate inflammation and alleviate the axonal hypomyelination in the corpus callosum in septic postnatal rats. We further explored if this might be related to the modulation of microglial polarization from M1 phenotype to M2 through the JAK2/STAT3/telomerase pathway. We reported here that indeed melatonin not only can it reduce the neurobehavioral disturbances in LPS-injected rats, but it can also dampen microglia-mediated inflammation. Thus, in LPS + melatonin group, the expression of proinflammatory mediators in M1 phenotype microglia was downregulated. As opposed to this, M2 microglia were increased which was accompanied by upregulated expression of anti-inflammatory mediators along with telomerase reverse transcriptase or melatonin receptor 1(MT1). In parallel to this was decreased NG2 expression but increased expression of myelin and neurofilament proteins. Melatonin can improve hypomyelination which was confirmed by electron microscopy. In vitro in primary microglia stimulated by LPS, melatonin decreased the expression of proinflammatory mediators significantly; but it increased the expression of anti-inflammatory mediators. Additionally, the expression levels of p-JAK2 and p-STAT3 were significantly elevated in microglia after melatonin treatment. Remarkably, the effect of melatonin on LPS-treated microglia was blocked by melatonin receptor, JAK2, STAT3 and telomerase reverse transcriptase inhibitors, respectively. Taken together, it is concluded that melatonin can attenuate PWMD through shifting M1 microglia towards M2 via MT1/JAK2/STAT3/telomerase pathway. The results suggest a new therapeutic strategy whereby melatonin may be adopted to convert microglial polarization from M1 to M2 phenotype that would ultimately contribute to the attenuation of PWMD.


Assuntos
Axônios/efeitos dos fármacos , Melatonina/farmacologia , Microglia/efeitos dos fármacos , Bainha de Mielina/efeitos dos fármacos , Doenças Neuroinflamatórias/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Axônios/metabolismo , Polaridade Celular/efeitos dos fármacos , Janus Quinase 2/metabolismo , Lipopolissacarídeos/farmacologia , Melatonina/uso terapêutico , Microglia/metabolismo , Bainha de Mielina/metabolismo , Doenças Neuroinflamatórias/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Ratos , Fator de Transcrição STAT3/metabolismo , Telomerase/metabolismo , Substância Branca/efeitos dos fármacos , Substância Branca/metabolismo
15.
J Inflamm Res ; 14: 5919-5937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803390

RESUMO

BACKGROUND: Astrocyte A1/A2 phenotypes may play differential role in the pathogenesis of periventricular white matter (PWM) damage in septic postnatal rats. This study aimed to determine whether melatonin (MEL) would improve the axonal hypomyelination through shifting A1 astrocytes towards A2. METHODS: One-day-old Sprague-Dawley rats were divided into control, LPS, and LPS+MEL groups. Immunofluorescence was performed to detect C1q, IL-1α, TNF-α, IBA1, GFAP, MAG, C3 and S100A10 immunoreactivity in the PWM of neonatal rats. Electron microscopy was conducted to observe alterations of axonal myelin sheath in the PWM; moreover, myelin protein expression was assessed using in situ hybridization. The effects of MEL on neurological function were evaluated by behavioral tests. In vitro, A1 astrocytes were induced by IL-1α, C1q and TNF-α, and following which the effect of MEL on C3 and S100A10 expression was determined by Western blot and immunofluorescence. RESULTS: At 1 and 3 days after LPS injection, IBA1+ microglia in the PWM were significantly increased in cell numbers which generated excess amounts of IL-1α, TNF-α, and C1q. The number of A1 astrocytes was significantly increased at 7-28d after LPS injection. In rats given MEL treatment, the number of A1 astrocytes was significantly decreased, but that of A2 astrocytes, PLP+, MBP+ and MAG+ cells was increased. By electron microscopy, ultrastructural features of axonal hypomyelination were attenuated by MEL. Furthermore, MEL improved neurological dysfunction as evaluated by different neurological tests. In vitro, MEL decreased the C3 significantly, and upregulated expression of S100A10 in primary astrocytes subjected to IL-1α, TNF-α and C1q treatment. Importantly, JAK2/STAT3 signaling pathway was found to be involved in modulation of A1/A2 phenotype transformation. CONCLUSION: MEL effectively alleviates PWMD of septic neonatal rats, which is most likely through modulating astrocyte phenotypic transformation from A1 to A2 via the MT1/JAK2/STAT3 pathway.

16.
J Biomed Nanotechnol ; 17(4): 582-594, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35057885

RESUMO

Iron oxide nanomaterials with mimic enzymes activity have been paid more attention in the clinical diagnosis field. The modified surface molecules would influence the catalytic activity of nanozyme, which is worth studying. Furthermore, the traditional detection strategy is based on colorimetric change of substrates, however, the optical signal is easy to be interfered in complex biological applications. In our research, an efficient and facile preparation strategy was developed to obtain functional artificial nanozymes. Herein, three kinds of surfactants, including citrate acid, poly(ethylene glycol) bis (carboxymethyl) ether and tannic acid have been applied to modify these nanomaterials that showed uniform size, high soluble dispersity and stability. Furthermore, these nanozymes exhibited different peroxidase-like activity to catalyze the hydrogen peroxide and 3,3',5,5'-tetramethylbenzidine. More importantly, magnetic relaxation effect of iron oxide nanozymes was found to be changed during the catalytic reaction. In addition, the relationship between the magnetic signal of nanozymes and the substrate concentration showed a good linear dependence. Combined with the natural enzymes, the magnetic detection of iron oxide nanozymes also exhibited excellent substrate specificity. On these bases, a dual-function specific assay was constructed and further used for glucose detection. In conclusion, this study demonstrated an efficient iron oxide nanozymes preparation method and constructed a new synergistically colorimetric-magnetic diagnosis strategy.


Assuntos
Colorimetria , Compostos Férricos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
17.
Biomed Res Int ; 2021: 5089371, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33959656

RESUMO

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer due to its lack of treatment options. Patients with TNBC frequently develop resistance to chemotherapy. As epigenetic-based antineoplastic drugs, histone deacetylase inhibitors (HDACis) have achieved particular efficacy in lymphoma but are less efficacious in solid tumors, and the resistance mechanism remains poorly understood. In this study, the GSE129944 microarray dataset from the Gene Expression Omnibus database was downloaded, and fold changes at the transcriptome level of a TNBC line (MDA-MB-231) after treatment with belinostat were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were used to identify the critical biological processes. Construction and analysis of the protein-protein interaction (PPI) network were performed to screen candidate genes related to cancer prognosis. A total of 465 DEGs were identified, including 240 downregulated and 225 upregulated genes. The cytokine-cytokine receptor pathway was identified as being significantly changed. Furthermore, the expression of CXCL1 was implicated as a favorable factor in the overall survival of breast cancer patients. With in vitro approaches, we also showed that belinostat could induce the expression of CXCL1 in another 2 TNBC cell lines (BT-549 and HCC-1937). We speculate that belinostat-induced CXCL1 expression could be one of the results of the stress clone evolution of cells after HDACi treatment. These findings provide new insights into clone evolution during HDACi treatment, which might guide us to a novel perspective that various mutation-targeted treatments should be implemented during the whole treatment cycle.


Assuntos
Quimiocina CXCL1/genética , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Sulfonamidas/farmacologia , Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Evolução Molecular , Feminino , Humanos , Prognóstico , Mapas de Interação de Proteínas/efeitos dos fármacos , Mapas de Interação de Proteínas/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
18.
J Hazard Mater ; 390: 122014, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32007858

RESUMO

Aluminum substitution is common in iron (hydr)oxides in subsurface environments, and can significantly modify mineral interactions with contaminants. However, few studies investigate Cr(VI) adsorption and its subsequent mobility on Al-substituted iron (hydr)oxide surfaces. Here shows that Al substitution gradually modifies hematite crystals from {101}, {112}, {110} and {104} faceted rhombohedra to {001} faceted plates, resulting in a general decrease in Cr(VI) adsorption density and favoring of monodentate mononuclear over bidentate binuclear Cr(VI) adsorption complexes. Consequently, the mobility of Cr(VI) might be increased in environments with an abundance of Al-containing iron (hydr)oxides. However, pre-adsorption of Fe2+ on hematite promotes Cr(VI) adsorption, reduction and fixation, and Al-substituted hematite removes more Cr(VI) than pure hematite. Similarly, although addition of Fe2+ to Cr(VI)-adsorbed hematite remobilizes a small proportion of Cr, it greatly increases the proportion of Cr fixed. As the coexistence of Fe2+ and iron (hydr)oxides is common in subsurface environments, Al-containing iron (hydr)oxides will promote Cr(VI) uptake and retention, with a significant proportion fixed as Cr(III), limiting Cr mobility and toxicity. These results offer new insights into how iron (hydr)oxides might control the behaviors of other high-valence redox-sensitive contaminants, and provide a platform for modeling such processes in complex soil and sediment systems.

19.
Brain Pathol ; 30(3): 495-514, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31622511

RESUMO

Neuroinflammation is thought to play a pivotal role in the pathogenesis of periventricular white matter (PWM) damage (PWMD) induced by neonatal sepsis. Because the complement cascade is implicated in inflammatory response, this study was carried out to determine whether C3a is involved in PWMD, and, if so, whether it would induce axonal hypomyelination. Furthermore, we explored if C3a would act through its C3a receptor (C3aR) and thence inhibit maturation of oligodendrocyte precursor cells (OPCs) via the WNT/ß-catenin signal pathway. Sprague Dawley (SD) rats aged 1 day were intraperitoneally injected with lipopolysaccharide (LPS) (1 mg/kg). C3a was upregulated in activated microglia and astrocytes in the PWM up to 7 days after LPS injection. Concomitantly, enhanced C3aR expression was observed in NG2+ oligodendrocytes (OLs). Myelin proteins including CNPase, PLP, MBP and MAG were significantly reduced in the PWM of 28-day septic rats. The number of PLP+ and MBP+ cells was markedly decreased. By electron microscopy, myelin sheath thickness was thinner and the average g-ratios were higher. This was coupled with an increase in number of NG2+ cells and decreased number of CC1+ cells. Olig1, Olig2 and SOX10 protein expression was significantly reduced in the PWM after LPS injection. Very strikingly, C3aRa administration for the first 7 days could reverse the above-mentioned pathological alterations in the PWM of septic rats. When incubated with C3a, expression of MBP, CNPase, PLP, MAG, Olig1, Olig2, SOX10 and CC1 in primary cultured OPCs was significantly downregulated as opposed to increased NG2. Moreover, WNT/ß-catenin signaling pathway was found to be implicated in inhibition of OPCs maturation and differentiation induced by C3a in vitro. As a corollary, it is speculated that C3a in the PWM of septic rats is closely associated with the disorder of OPCs differentiation and maturation through WNT/ß-catenin signaling pathway, which would contribute ultimately to axonal hypomyelination.


Assuntos
Complemento C3a/metabolismo , Doenças Desmielinizantes/etiologia , Bainha de Mielina/patologia , Sepse Neonatal/complicações , Substância Branca/patologia , Via de Sinalização Wnt/fisiologia , Animais , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Células Cultivadas , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Lipopolissacarídeos , Bainha de Mielina/metabolismo , Sepse Neonatal/induzido quimicamente , Sepse Neonatal/metabolismo , Sepse Neonatal/patologia , Células Precursoras de Oligodendrócitos/metabolismo , Células Precursoras de Oligodendrócitos/patologia , Ratos , Ratos Sprague-Dawley , Regulação para Cima , Substância Branca/metabolismo
20.
Neuromolecular Med ; 22(3): 420-436, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32638208

RESUMO

Neonatal sepsis is associated with cognitive deficit in the later life. Axonal myelination plays a pivotal role in neurotransmission and formation of learning and memory. This study aimed to explore if systemic lipopolysaccharide (LPS) injection would induce hypomyelination in the prefrontal cortex and hippocampus in developing septic neonatal rats. Sprague-Dawley rats (1-day old) were injected with LPS (1 mg/kg) intraperitoneally. By electron microscopy, axonal hypomyelination was evident in the subcortical white matter and hippocampus. The expression of myelin proteins including CNPase, MBP, PLP and MAG was downregulated in both areas of the brain at 7, 14 and 28 days after LPS injection. The frequency of MBP and PLP-positive oligodendrocyte was significantly reduced using in situ hybridization in the cerebral cortex and hippocampus at the corresponding time points after LPS injection, whereas the expression of NG2 and PDGFRα was noticeably increased. In tandem with this was reduction of Olig1 and Olig2 expressions which are involved in differentiation/maturation of OPCs. Expression of NFL, NFM, and NFH was significantly downregulated, indicating that axon development was disrupted after LPS injection. Morris Water Maze behavioral test, Open field test, Rotarod test, and Pole test were used to evaluate neurological behaviors of 28 days rats. The rats in the LPS group showed the impairment of motor coordination, balance, memory, and learning ability and represented bradykinesia and anxiety-like behavior. The present results suggest that following systemic LPS injection, differentiation/maturation of OPCs was affected which may be attributed to the inhibition of transcription factors Olig1 and Olig2 expression resulting in impairment to axonal development. It is suggested that this would ultimately lead to axonal hypomyelination in the prefrontal cortex and hippocampus, which may be associated with neurological deficits in later life.


Assuntos
Hipocampo/patologia , Proteínas da Mielina/deficiência , Transtornos do Neurodesenvolvimento/etiologia , Córtex Pré-Frontal/patologia , Sepse/patologia , Substância Branca/patologia , Animais , Animais Recém-Nascidos , Ansiedade/etiologia , Axônios/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Hipocampo/metabolismo , Hipocinesia/etiologia , Lipopolissacarídeos/toxicidade , Masculino , Transtornos da Memória/etiologia , Microscopia Eletrônica , Teste do Labirinto Aquático de Morris , Proteínas da Mielina/biossíntese , Proteínas da Mielina/genética , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Células Precursoras de Oligodendrócitos/metabolismo , Células Precursoras de Oligodendrócitos/patologia , Fator de Transcrição 2 de Oligodendrócitos/biossíntese , Fator de Transcrição 2 de Oligodendrócitos/genética , Oligodendroglia/patologia , Teste de Campo Aberto , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley , Teste de Desempenho do Rota-Rod , Sepse/complicações , Sepse/metabolismo
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