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3.
Oncol Lett ; 23(4): 117, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35261631

RESUMO

Breast cancer is among the most frequently diagnosed cancer types and the leading cause of cancer-related death in women. The mortality rate of patients with breast cancer is currently increasing, perhaps due to a lack of early screening tools. In the present study, using The Cancer Genome Atlas (TCGA) breast cancer dataset (n=883), it was determined that methylation of the protocadherin ß15 (PCDHB15) promoter was higher in breast cancer samples than that in normal tissues. A negative association between promoter methylation and expression of PCDHB15 was observed in the TCGA dataset and breast cancer cell lines. In TCGA cohort, lower PCDHB15 expression was associated with shorter relapse-free survival times. Treatment with the DNA methyltransferase inhibitor restored PCDHB15 expression in a breast cancer cell line; however, overexpression of PCDHB15 was shown to suppress colony formation. PCDHB15 methylation detected in circulating cell-free DNA (cfDNA) isolated from serum samples was higher in patients with breast cancer (40.8%) compared with that in patients with benign tumors (22.4%). PCDHB15 methylation was not correlated with any clinical parameters. Taken together, PCDHB15 is a potential tumor suppressor in cases of breast cancer, which can be epigenetically silenced via promoter methylation. PCDHB15 methylation using cfDNA is a novel minimally invasive epigenetic biomarker for the diagnosis and prognosis of breast cancer.

4.
New Phytol ; 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35358343

RESUMO

Plant lateral root (LR) growth usually is stimulated by arbuscular mycorrhizal (AM) symbiosis. However, the molecular mechanism is still unclear. We used gene expression analysis, peptide treatment and virus-induced gene alteration assays to demonstrate that C-terminally encoded peptide (CEP2) expression in tomato was downregulated during AM symbiosis to mitigate its negative effect on LR formation through an auxin-related pathway. We showed that enhanced LR density and downregulated CEP2 expression were observed during mycorrhizal symbiosis. Synthetic CEP2 peptide treatment reduced LR density and impaired the expression of genes involved in indole-3-butyric acid (IBA, the precursor of IAA) to IAA conversion, auxin polar transport and the LR-related signaling pathway; however, application of IBA or synthetic auxin 1-naphthaleneacetic acid (NAA) to the roots may rescue both defective LR formation and reduced gene expression. CEP receptor 1 (CEPR1) might be the receptor of CEP2 because its knockdown plants did not respond to CEP2 treatment. Most importantly, the LR density of CEP2 overexpression or knockdown plants could not be further increased by AM inoculation, suggesting that CEP2 was critical for AM-induced LR formation. These results indicated that AM symbiosis may regulate root development by modulating CEP2, which affects the auxin-related pathway.

5.
ACS Nano ; 16(3): 3449-3475, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35225606

RESUMO

The ability to meet higher effluent quality requirements and the reduction of energy consumption are the biggest challenges in wastewater treatment worldwide. A large proportion of the energy generated during wastewater treatment processes is neglected and lost in traditional wastewater treatment plants. As a type of energy harvesting system, triboelectric nanogenerators (TENGs) can extensively harvest the microscale energies generated from wastewater treatment procedures and auxiliary devices. This harvested energy can be utilized to improve the removal efficiency of pollutants through photo/electric catalysis, which has considerable potential application value in wastewater treatment plants. This paper gives an overall review of the generated potential energies (e.g., water wave energy, wind energy, and acoustic energy) that can be harvested at various stages of the wastewater treatment process and introduces the application of TENG devices for the collection of these neglected energies during wastewater treatment. Furthermore, the mechanisms and catalytic performances of TENGs coupled with photo/electric catalysis (e.g., electrocatalysis, photoelectric catalysis) are discussed to realize higher pollutant removal efficiencies and lower energy consumption. Then, a thorough, detailed investigation of TENG devices, electrode materials, and their coupled applications is summarized. Finally, the intimate coupling of self-powered photoelectric catalysis and biodegradation is proposed to further improve removal efficiencies in wastewater treatment. This concept is conducive to improving knowledge about the underlying mechanisms and extending applications of TENGs in wastewater treatment to better solve the problems of energy demand in the future.


Assuntos
Fontes de Energia Elétrica , Purificação da Água , Eletricidade , Eletrodos , Nanotecnologia/métodos
6.
Environ Sci Pollut Res Int ; 29(20): 30337-30347, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34997490

RESUMO

Owing to containing high fraction of organic matter, the tannery sludge seemed to be fit for composting. Actually, it was intensively harmful to the environment, due to containing chromium (Cr). So it might undergo a long time of storage until finding a proper way to dispose it. In the storage period, it would expose the surrounding environment a risk via releasing Cr. In this study, an approach was proposed to minimize the amount of released Cr, and reveal the mechanism on immobilizing Cr. Collagen protein waste (CPW) was adopted to immobilize Cr, and it was evaluated via leaching experiment. The lowest leaching concentration of Cr was 12 mg/L, meeting the limits of related standard in China (GB 5085.3-2007, Tcr < 15 mg/L). Moreover, the compositions and functional groups of the optimum sample (12 mg/L) were also characterized, confirming that the dominant functional groups cross-linking with Cr were hydroxyl (-OH), carboxyl (-COOH), and epoxy (-COC). Importantly, density functional theory (DFT) calculation was also employed, suggesting that Cr was restrained by accepting electrons from O atoms donating by functional groups.


Assuntos
Cromo , Esgotos , Cromo/análise , Colágeno , Resíduos Industriais/análise , Curtume
7.
Invest Radiol ; 57(4): 242-253, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34743134

RESUMO

BACKGROUND: Radiomics can yield minable information from medical images, which can facilitate computer-aided diagnosis. However, the lack of repeatability and reproducibility of radiomic features (RFs) may hinder their generalizability in clinical applications. OBJECTIVES: The aims of this study were to explore 3 main sources of variability in RFs, investigate their influencing magnitudes and patterns, and identify a subset of robust RFs for further studies. MATERIALS AND METHODS: A chest phantom with nodules was scanned with different computed tomography (CT) scanners repeatedly with varying acquisition and reconstruction parameters (April-May 2019) to evaluate 3 sources of variability: test-retest, inter-CT, and intra-CT protocol variability. The robustness of the RFs was measured using the concordance correlation coefficient, dynamic range, and intraclass correlation coefficient (ICC). The influencing magnitudes and patterns were analyzed using the Friedman test and Spearman rank correlation coefficient. Stable and informative RFs were selected, and their redundancy was eliminated using hierarchical clustering. Clinical validation was also performed to verify the clinical effectiveness and potential enhancement of the generalizability of radiomics research. RESULTS: A total of 1295 RFs that showed all 3 sources of variability were included. The reconstruction kernel and the iteration level showed the greatest (ICC, 0.35 ± 0.31) and the least (ICC, 0.63 ± 0.27) influence on magnitudes. The different sources of variability showed relatively consistent patterns of influence (false discovery rate <0.001). Finally, we obtained a subset of 19 stable, informative, and nonredundant RFs under all 3 sources of variability. These RFs exhibited clinical effectiveness and showed better prediction performance than unstable RFs in the validation dataset (P = 0.017, Delong test). CONCLUSIONS: The stability of RFs was affected to different degrees by test-retest and differences in CT manufacturers and models and CT acquisition and reconstruction parameters, but the influences of these factors showed relatively consistent patterns. We also obtained a subset of 19 stable, informative, and nonredundant RFs that should be preferably used to enhance the generalizability of further radiomics research.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/métodos
8.
Chemistry ; 28(4): e202103452, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34792224

RESUMO

Oxidation of the iron(II) precursor [(L1 )FeII Cl2 ], where L1 is a tetradentate bispidine, with soluble iodosylbenzene (s PhIO) leads to the extremely reactive ferryl oxidant [(L1 )(Cl)FeIV =O]+ with a cis disposition of the chlorido and oxido coligands, as observed in non-heme halogenase enzymes. Experimental data indicate that, with cyclohexane as substrate, there is selective formation of chlorocyclohexane, the halogenation being initiated by C-H abstraction and the result of a rebound of the ensuing radical to an iron-bound Cl- . The time-resolved formation of the halogenation product indicates that this primarily results from s PhIO oxidation of an initially formed oxido-bridged diiron(III) resting state. The high yield of up to >70 % (stoichiometric reaction) as well as the differing reactivities of free Fe2+ and Fe3+ in comparison with [(L1 )FeII Cl2 ] indicate a high complex stability of the bispidine-iron complexes. DFT analysis shows that, due to a large driving force and small triplet-quintet gap, [(L1 )(Cl)FeIV =O]+ is the most reactive small-molecule halogenase model, that the FeIII /radical rebound intermediate has a relatively long lifetime (as supported by experimentally observed cage escape), and that this intermediate has, as observed experimentally, a lower energy barrier to the halogenation than the hydroxylation product; this is shown to primarily be due to steric effects.


Assuntos
Carbono , Halogenação , Compostos Férricos , Ligação de Hidrogênio , Ferro
9.
J Hazard Mater ; 424(Pt D): 127680, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34799171

RESUMO

In this study, based on the differences in the coordination configurations of various alkaline earth metal ions (Ca(Ⅱ) and Sr(Ⅱ)) and sodium alginate (SA), the aerogel is functionalized with controllable slit-shaped pores structure, contributing by nanosheet stacking impact of graphene oxide (GO) and montmorillonite (MMT), which is able to selectively remove plane hydrate copper ions in complex wastewater systems. Sr-G/M is endowed with denser slit-shaped pores and could achieve more efficient selective removal of Cu(Ⅱ), together with a best removal efficiency of 97.1%, proving by systematic adsorption tests. The selectivity tests show that Sr-G/M exhibits preferential adsorption for Cu(Ⅱ) with a distribution coefficient of 41.85 L g-1. Furthermore, Sr-G/M has excellent regeneration performance to be 86.4% after 8 recycles. Considering its cost-effectiveness, eco-friendliness, easy preparation and efficient selective removal performance, Sr-G/M holds great promise in selective removal of Cu(Ⅱ) from complex wastewater systems.

10.
Magn Reson Imaging ; 85: 80-86, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34666158

RESUMO

OBJECTIVES: To develop and validate a radiomics nomogram for differentiating between malignant pulmonary nodules and benign nodules. METHODS: 56 benign and 51 malignant nodules from 96 patients were analyzed using manual segmentation of the T2-fBLADE-TSE, while the nodules signal intensity (SIlesion), lesion muscle ratio (LMR) and nodule size were all measured and recorded. The maximum relevance and minimum redundancy (mRMR) and the least absolute shrinkage and selection operator (LASSO) were used to select nonzero coefficients and develop the model in pulmonary nodules diagnosis. The radiomics nomogram was also developed. The clinical prediction value was determined by the decision curve analysis (DCA). RESULTS: The nodule size, SIlesion and LMR of the benign group were 1.78 ± 0.57 cm, 227.50 ± 81.39 and 2.40 ± 1.27 respectively, in contrast to the 2.00 ± 0.64 cm, 232.87 ± 82.21 and 2.17 ± 0.91, respectively, in the malignant group (P = 0.09, 0.60 and 0.579). A total of 13 radiomics features were retained. The Rad-score of the benign nodules group was lower than that of the malignant nodules group (P < 0.001 & 0.049, training & test set). The AUC of radiomics signature for nodules diagnosis was 0.82 (95% CI, 0.73-0.91) in the training set and 0.71 (95% CI, 0.51-0.90) in the test set. A nomogram, consisting of 13 radiomics features and nodule size, produced good prediction in the training set (AUC, 0.82; 95% CI, 0.73-0.91), which was significantly better than that of T2-based quantitative parameters (AUC, 0.62; 95% CI, 0.50-0.75, P = 0.003). In the test set, the performance of radiomics nomogram (AUC, 0.70; 95% CI, 0.51-0.90) was also better than that of T2-based quantitative parameters (AUC, 0.46; 95% CI, 0.25-0.67) (P = 0.145). The DCA showed that radiomics nomogram and T2-based quantitative parameter had overall net benefits, while the performance of nomogram was better. CONCLUSION: We constructed and validated a T2-fBLADE-TSE-based radiomics nomogram that can help to differentiate between malignant pulmonary nodules and benign nodules.


Assuntos
Neoplasias Pulmonares , Nomogramas , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
Anal Chim Acta ; 1181: 338898, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34556238

RESUMO

The low image acquisition speed of terahertz (THz) time-domain imaging systems limits their application in biological products analysis. In the current study, a local pixel graph neural network was built for THz time-domain imaging super-resolution. The method could be applied to the analysis of any heterogeneous biological products as it only required a small number of sample images for training and particularly it focused on THz feature frequencies. The graph network applied the Fourier transform to graphs extracted from low-resolution (LR) images bringing an invariance of rotation and flip for local pixels, and the network then learnt the relationship between the state of graphs and the corresponding pixels to be reconstructed. With wood cores and seeds as examples, the images of these samples were captured by a THz time-domain imaging system for training and analysed by the method, achieving the root mean square error (RMSE) of pixels of 0.0957 and 0.1061 for the wood core and seed images, respectively. In addition, the reconstructed high-resolution (HR) images, LR images and true HR images at several feature frequencies were also compared in the current study. Results indicated that the method could not only reconstruct the spatial details and the useful signals from high noise signals at high feature frequencies but could also operate super-resolution in both spatial and spectral aspects.


Assuntos
Produtos Biológicos , Redes Neurais de Computação
12.
Front Aging Neurosci ; 13: 705287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335234

RESUMO

Perioperative neurocognitive disorder (PND) is a common condition in elderly patients undergoing surgery. Sedation, analgesia, regional cerebral oxygen saturation (rSO2), and body temperature are known to be associated with PND, but few studies have examined the contribution of these factors combined in detail. This prospective, randomized, controlled, double-blinded study investigated whether anesthesia management based on multimodal brain monitoring-an anesthesia management algorithm designed by our group-could improve the post-operative cognitive function and brain functional connectivity (FC) in elderly patients undergoing elective spinal surgery with general anesthesia. The patients (aged ≥65 years) were randomized into two groups [control (Group C), n = 12 and intervention (Group I), n = 14]. Patients in Group I were managed with multimodal brain monitoring (patient state index, spectral edge frequency, analgesia nociception index, rSO2, and temperature), and those in Group C were managed with routine anesthesia management. All patients were pre- and post-operatively evaluated (7 days after surgery) with the Montreal Cognitive Assessment (MoCA). Amplitude of low-frequency fluctuation (ALFF) and FC were analyzed after resting-state functional MRI. Serum C-reactive protein (CRP) and lipopolysaccharide levels were measured, and the correlation between FC and changes in inflammatory marker levels was analyzed. Mean post-operative MoCA score was higher in Group I (24.80 ± 2.09) than in Group C (22.56 ± 2.24) (p = 0.04), with no difference in PND incidence between groups (28.57 vs. 16.67%; p = 0.47). Group I also showed significantly increased ALFF values in several brain regions after surgery (p < 0.05), and FC between the left hippocampus and left orbital inferior frontal gyrus (FG), left middle FG, left superior temporal gyrus, and left precentral gyrus was enhanced (p < 0.05), which was negatively correlated with the change in serum CRP (pre vs. post-intervention) (R = -0.58, p = 0.01). These results suggest that management of elderly patients undergoing surgery by multimodal brain monitoring may improve post-operative neurocognition and FC by reducing systemic inflammation. Clinical Trial Registration: http://www.chictr.org.cn/index.aspx, identifier: ChiCTR1900028024.

13.
ACS Appl Mater Interfaces ; 13(35): 41875-41885, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34449194

RESUMO

Imparting surface coatings with conductivity is an effective way to prevent fire and explosion caused by electrostatic discharge. TiO2 is a commonly used paint; however, intrinsic TiO2 has poor electrical conductivity. Herein, we develop a method to make TiO2 coating highly conductive by doping Ca2+ into the TiO2 lattice based on the introduction of graphene. It is demonstrated that doping Ca2+ increases the carrier density of TiO2 and its morphology changes from a sphere to a spindle shape, which increases the interfacial contact area between TiO2 and graphene. Therefore, resistivity can be greatly decreased due to the construction of fast charge transport pathways from TiO2 to graphene, resulting from an increase in the speed of interfacial charge transfer. In addition, the electronic properties of the samples are also studied through first-principles calculations before and after Ca2+ doping. The result of the theoretical analysis is in agreement with that of experiments. Thus, the lowest resistivity of Ca2+-TiO2/graphene can reach 0.004 Ω cm. Consequently, the feature of superior conductivity of the Ca2+-TiO2/graphene composite endows it with practical application potential in the field of antistatic coating.

14.
Neuroscience ; 467: 47-55, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34022324

RESUMO

With a greatly changed environment, sleep problem becomes a common phenomenon among college freshmen. However, this type of acute insomnia usually recovers after adapting to the circumstances, which can be defined as adaptive sleep problem (ASP). Few studies deal with this type of sleep problems. In this study, 991 first-year college freshmen were recruited on different days of the first semester to investigate their sleep status. We found that the sleep problem of college freshmen at the beginning of the semester was the most severe, compared with the other two-thirds of semester. Next, behavioral and resting-state functional magnetic imaging (rs-fMRI) data from 30 freshmen with ASP and 28 matched healthy controls (HC) were used to explore the neural basis of acute insomnia. Results showed that ASP group performed worse on many behavioral indices, such as fatigue, depression, and trait anxiety. Interestingly, students with ASP also showed significantly more negative functional connectivity between the anterior default mode network (aDMN) and the dorsal attentional network (DAN). Furthermore, a significant negative correlation was observed between Insomnia Severity Index (ISI) score and aDMN-DAN functional connectivity in the HC group, which was not observed in the case of ASP. In conclusion, the study explored the neural biomarker of adaptive sleep problem (ASP) in freshmen, and found its potentiating antagonism within the DMN-DAN. This enhanced anticorrelation may corroborate that students with ASP are in a hyperarousal state. Our current study may deepen our understanding of sleep disorders, and the enhanced anticorrelation may corroborate that ASP in due to a hyperarousal state.


Assuntos
Imageamento por Ressonância Magnética , Distúrbios do Início e da Manutenção do Sono , Atenção , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Rede de Modo Padrão , Humanos , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem
15.
PLoS One ; 16(4): e0250115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914764

RESUMO

Trade credit is a payment extension granted by a selling firm to its customer. Companies typically respond to late payments from their customers by delaying payments to suppliers, thus generating a ripple through the transaction network. Therefore, trade credit is as a potential vehicle of propagation of losses in case of default events. The goal of this work is to leverage information on the trade credit among connected firms to predict imminent defaults of firms. We use a unique dataset of client firms of a major Italian bank to investigate firm bankruptcy between October 2016 to March 2018. We develop a model to capture network spillover effects originating from the supply chain on the probability of default of each firm via a sequential approach: the output of a first model component on single firm features is used in a subsequent model which captures network spillovers. While the first component is the standard econometrics way to predict such dynamics, the network module represents an innovative way to look into the effect of trade credit on default probability. This module looks at the transaction network of the firm, as inferred from the payments transiting via the bank, in order to identify the trade partners of the firm. By using several features extracted from the network of transactions, this model is able to predict a large fraction of the defaults, thus showing the value hidden in the network information. Finally, we merge firm and network features with a machine learning model to create a 'hybrid' model, which improves the recall for the task by almost 20 percentage points over the baseline.


Assuntos
Administração Financeira/economia , Previsões/métodos , Corporações Profissionais/economia , Falência da Empresa/economia , Comércio/economia , Comércio/estatística & dados numéricos , Humanos , Aprendizado de Máquina , Modelos Econômicos , Probabilidade
16.
Viruses ; 13(3)2021 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804667

RESUMO

While SARS-CoV-2 specific neutralizing antibodies have been developed for therapeutic purposes, the specific viral triggers that drive the generation of SARS-CoV-2 specific IgG and IgM antibodies remain only partially characterized. Moreover, it is unknown whether endogenously derived antibodies drive viral clearance that might result in mitigation of clinical severity during natural infection. We developed a series of non-linear mathematical models to investigate whether SARS-CoV-2 viral and antibody kinetics are coupled or governed by separate processes. Patients with severe disease had a higher production rate of IgG but not IgM antibodies. Maximal levels of both isotypes were governed by their production rate rather than different saturation levels between people. Our results suggest that an exponential surge in IgG levels occurs approximately 5-10 days after symptom onset with no requirement for continual antigenic stimulation. SARS-CoV-2 specific IgG antibodies appear to have limited to no effect on viral dynamics but may enhance viral clearance late during primary infection resulting from the binding effect of antibody to virus, rather than neutralization. In conclusion, SARS-CoV-2 specific IgG antibodies may play only a limited role in clearing infection from the nasal passages despite providing long-term immunity against infection following vaccination or prior infection.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , Imunoglobulina G/imunologia , Nariz/virologia , SARS-CoV-2/fisiologia , Anticorpos Neutralizantes/imunologia , COVID-19/virologia , Humanos , Imunoglobulina M/imunologia , Estudos Longitudinais , Nariz/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Eliminação de Partículas Virais
17.
Ann Transl Med ; 9(3): 216, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33708843

RESUMO

BACKGROUND: The assessment of the severity of coronavirus disease 2019 (COVID-19) by clinical presentation has not met the urgent clinical need so far. We aimed to establish a deep learning (DL) model based on quantitative computed tomography (CT) and initial clinical features to predict the severity of COVID-19. METHODS: One hundred ninety-six hospitalized patients with confirmed COVID-19 were enrolled from January 20 to February 10, 2020 in our centre, and were divided into severe and non-severe groups. The clinico-radiological data on admission were retrospectively collected and compared between the two groups. The optimal clinico-radiological features were determined based on least absolute shrinkage and selection operator (LASSO) logistic regression analysis, and a predictive nomogram model was established by five-fold cross-validation. Receiver operating characteristic (ROC) analyses were conducted, and the areas under the receiver operating characteristic curve (AUCs) of the nomogram model, quantitative CT parameters that were significant in univariate analysis, and pneumonia severity index (PSI) were compared. RESULTS: In comparison with the non-severe group (151 patients), the severe group (45 patients) had a higher PSI (P<0.001). DL-based quantitative CT indicated that the mass of infection (MOICT) and the percentage of infection (POICT) in the whole lung were higher in the severe group (both P<0.001). The nomogram model was based on MOICT and clinical features, including age, cluster of differentiation 4 (CD4)+ T cell count, serum lactate dehydrogenase (LDH), and C-reactive protein (CRP). The AUC values of the model, MOICT, POICT, and PSI scores were 0.900, 0.813, 0.805, and 0.751, respectively. The nomogram model performed significantly better than the other three parameters in predicting severity (P=0.003, P=0.001, and P<0.001, respectively). CONCLUSIONS: Although quantitative CT parameters and the PSI can well predict the severity of COVID-19, the DL-based quantitative CT model is more efficient.

18.
Front Aging Neurosci ; 13: 600484, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732135

RESUMO

Neuroinflammation has been recognized as a major cause for neurocognitive diseases. Although the hippocampus has been considered an important region for cognitive dysfunction, the influence of hippocampal neuroinflammation on brain functional connectivity (FC) has been rarely studied. In this study, lipopolysaccharide (LPS) was used to induce systemic inflammation and neuroinflammation in the aged rat brain, while elamipretide (SS-31) was used for treatment. Systemic and hippocampal inflammation were determined using ELISA, while astrocyte responses during hippocampal neuroinflammation were determined by interleukin 1 beta (IL-1ß)/tumor necrosis factor alpha (TNFα) double staining immunofluorescence. Oxidative stress was determined by reactive oxidative species (ROS), electron transport chain (ETC) complex, and superoxide dismutase (SOD). Short- (<7 days) and long-term (>30 days) learning and spatial working memory were tested by the Morris water maze (MWM). Resting-state functional magnetic resonance imaging (rs-fMRI) was used to analyze the brain FC by placing seed voxels on the left and right hippocampus. Compared with the vehicle group, rats with the LPS exposure showed an impaired MWM performance, higher oxidative stress, higher levels of inflammatory cytokines, and astrocyte activation in the hippocampus. The neuroimaging examination showed decreased FC on the right orbital cortex, right olfactory bulb, and left hippocampus on day 3, 7, and 31, respectively, after treatment. In contrast, rats with SS-31 treatment showed lower levels of inflammatory cytokines, less astrocyte activation in the hippocampus, and improved MWM performance. Neuroimaging examination showed increased FC on the left-parietal association cortex (L-PAC), left sensory cortex, and left motor cortex on day 7 with the right flocculonodular lobe on day 31 as compared with those without SS-31 treatment. Our study demonstrated that inhibiting neuroinflammation in the hippocampus not only reduces inflammatory responses in the hippocampus but also improves the brain FC in regions related to the hippocampus. Furthermore, early anti-inflammatory treatment with SS-31 has a long-lasting effect on reducing the impact of LPS-induced neuroinflammation.

19.
Mater Sci Eng C Mater Biol Appl ; 119: 111641, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321679

RESUMO

Constructing bioactive guided bone regeneration (GBR) membranes that possess biological multifunctionality is becoming increasingly attractive and promising to meet higher requirements for bone healing. Given the biological responses following implantation, GBR process originates from an early inflammation-driven reaction adjacent to implanted membranes surface. However, to date there is relatively little attention paid to the critical immunoregulatory functions in traditionally designed GBR membranes. Herein, for the first time, we manipulate immunomodulatory properties of the widely-used native small intestinal submucosa (SIS) membrane by incorporating strontium-substituted nanohydroxyapatite coatings and/or IFN-γ to its surface. In vitro results reveal the obtained novel membrane SIS/SrHA/IFN-γ not only promote functions of endothelial cells and osteoblasts directly, but also energetically mediate a sequential M1-M2 macrophages transition to concurrently facilitate angiogenesis and osteogenesis. Moreover, in vivo outcomes of subcutaneous implantation and cranial defects repair further confirm its superior capacity to promote vascularization and in situ bone regeneration than pristine SIS through immunomodulation. These results demonstrate a sequential immunomodulatory strategy renders modified SIS membranes acting as a robust immunomodulator rather than a traditional barrier to significantly ameliorate in vivo GBR outcomes and hence provide important implications that may facilitate concerns on immunomodulatory properties for future GBR developments.


Assuntos
Células Endoteliais , Osteogênese , Regeneração Óssea , Imunomodulação , Membranas Artificiais
20.
Chin Med J (Engl) ; 134(3): 344-352, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33074843

RESUMO

BACKGROUND: Resting-state functional magnetic resonance imaging (rs-fMRI) is a promising method for the study of brain function. Typically, rs-fMRI is performed on anesthetized animals. Although different functional connectivity (FC) in various anesthetics on whole brain have been studied, few studies have focused on different FC in the aged brain. Here, we measured FC under three commonly used anesthesia methods and analyzed data to determine if the FC in whole brain analysis were similar among groups. METHODS: Twenty-four male aged Wistar rats were randomly divided into three groups (n = 8 in each group). Anesthesia was performed under either isoflurane (ISO), combined ISO + dexmedetomidine (DEX) or α-chloralose (AC) according to the groups. Data of rs-fMRI was analyzed by FC in a voxel-wise way. Differences in the FC maps between the groups were analyzed by one-way analysis of variance and post hoc two-sample t tests. RESULTS: Compared with ISO + DEX anesthesia, ISO anesthesia caused increased FC in posterior brain and decreased FC in the middle brain of the aged rat. AC anesthesia caused global suppression as no increase in FC was observed. CONCLUSION: ISO could be used as a substitute for ISO + DEX in rat default mode network studies if the left temporal association cortex is not considered important.


Assuntos
Anestesia , Isoflurano , Animais , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Masculino , Ratos , Ratos Wistar
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