Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 181
Filtrar
1.
Brain Imaging Behav ; 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34478055

RESUMO

Unilateral temporal lobe epilepsy (TLE) is the most common type of focal epilepsy characterized by foci in the unilateral temporal lobe grey matters of regions such as the hippocampus. However, it remains unclear how the functional features of white matter are altered in TLE. In the current study, resting-state functional magnetic resonance imaging (fMRI) was performed on 71 left TLE (LTLE) patients, 79 right TLE (RTLE) patients and 47 healthy controls (HC). Clustering analysis was used to identify fourteen white matter networks (WMN). The functional connectivity (FC) was calculated among WMNs and between WMNs and grey matter. Furthermore, the FC laterality of hemispheric WMNs was assessed. First, both patient groups showed decreased FCs among WMNs. Specifically, cerebellar white matter illustrated decreased FCs with the cerebral superficial WMNs, implying a dysfunctional interaction between the cerebellum and the cerebral cortex in TLE. Second, the FCs between WMNs and the ipsilateral hippocampus (grey matter foci) were also reduced in patient groups, which may suggest insufficient functional integration in unilateral TLE. Interestingly, RTLE showed more severe abnormalities of white matter FCs, including links to the bilateral hippocampi and temporal white matter, than LTLE. Taken together, these findings provide functional evidence of white matter abnormalities, extending the understanding of the pathological mechanism of white matter impairments in unilateral TLE.

2.
Water Sci Technol ; 84(3): 596-608, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34388121

RESUMO

The iron oxychloride/pillared montmorillonite (FeOCl/MMT) catalyst was prepared by wet impregnation method and solid melting method. Various characterization techniques were used to analyze the microscopic morphology and structure of a series of catalysts. Moreover, the catalysts were used to treat magenta-simulated dye wastewater through catalytic wet peroxide oxidation (CWPO) degradation. The magenta removal rate and chemical oxygen demand (COD) removal rate of the magenta-simulated dye wastewater were used to evaluate the catalytic performance of the catalyst, and the optimal catalyst preparation conditions were selected. The results showed that the solid melting method was more favorable to the preparation of the catalyst, and the COD removal rate of wastewater can reach 70.8% when the FeOCl load was 3%. Moreover, 96.2% of the magenta in the solution was removed. The COD removal rate of the magenta wastewater decreased by only 12.4% after the catalyst was repeatedly used six times, indicating that the catalyst has good activity and stability. The Fermi equation can simulate the reaction process of the catalyst treating magenta wastewater at high temperature.


Assuntos
Peróxidos , Águas Residuárias , Bentonita , Catálise , Peróxido de Hidrogênio , Oxirredução , Corantes de Rosanilina
3.
Chem Rev ; 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34342989

RESUMO

In nature, the self-assembly of sequence-specific biopolymers into hierarchical structures plays an essential role in the construction of functional biomaterials. To develop synthetic materials that can mimic and surpass the function of these natural counterparts, various sequence-defined bio- and biomimetic polymers have been developed and exploited as building blocks for hierarchical self-assembly. This review summarizes the recent advances in the molecular self-assembly of hierarchical nanomaterials based on peptoids (or poly-N-substituted glycines) and other sequence-defined synthetic polymers. Modern techniques to monitor the assembly mechanisms and characterize the physicochemical properties of these self-assembly systems are highlighted. In addition, discussions about their potential applications in biomedical sciences and renewable energy are also included. This review aims to highlight essential features of sequence-defined synthetic polymers (e.g., high stability and protein-like high-information content) and how these unique features enable the construction of robust biomimetic functional materials with high programmability and predictability, with an emphasis on peptoids and their self-assembled nanomaterials.

4.
Molecules ; 26(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203004

RESUMO

Green tea and its bioactive components, especially polyphenols, possess many health-promoting and disease-preventing benefits, especially anti-inflammatory, antioxidant, anticancer, and metabolic modulation effects with multi-target modes of action. However, the effect of tea polyphenols on immune function has not been well studied. Moreover, the underlying cellular and molecular mechanisms mediating immunoregulation are not well understood. This review summarizes the recent studies on the immune-potentiating effects and corresponding mechanisms of tea polyphenols, especially the main components of (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate (ECG). In addition, the benefits towards immune-related diseases, such as autoimmune diseases, cutaneous-related immune diseases, and obesity-related immune diseases, have been discussed.


Assuntos
Antioxidantes/farmacologia , Imunidade/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Polifenóis/farmacologia , Chá/química , Animais , Antioxidantes/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Humanos , Fatores Imunológicos/química , Polifenóis/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-34165755

RESUMO

We investigated three common alkaline agents (NaOH, CaO, and Mg(OH)2) for immobilization of four heavy metals (Pb, Zn, Cu, and Cd) in a field-contaminated soil and elucidated the underpinning principles. NaOH caused the highest pH spike in the soil, while CaO and Mg(OH)2 served as a longer-lasting source of OH-. Amending the soil with CaO or Mg(OH)2 at ≥0.1 mol as OH- (kg·soil)-1 for 24 h was able to immobilize all four metals, while NaOH failed. NaOH leached up to 3 times more organic carbon than CaO and Mg(OH)2, resulting in elevated leachability of the metals. Column elution tests showed that amendments by CaO and Mg(OH)2 lowered the leachable Pb2+, Zn2+, Cu2+, and Cd2+ by 52-54%, 71-75%, 69-73%, and 68%, respectively, after 1440 pore volumes of elution. Sequential extraction revealed that the soil amendments converted the exchangeable fraction of the metals to the much less available forms. XRD and FTIR analyses indicated that formation of metal oxide precipitates and complexation with soil organic matter were responsible for the metals immobilization. Taken together the chemical cost, technical effectiveness, and environmental impact, CaO is the most suitable alkaline agent for remediation of soil contaminated with heavy metals.

6.
J Phys Chem A ; 125(18): 3863-3873, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33945279

RESUMO

This paper reports a photophysical investigation of a series of phenylene ethynylene oligomers (OPE) that are end-substituted with a 1,8-naphthalene imide (NI) acceptor. The NI acceptor is attached to the terminus of the OPEs via an ethynylene (-C≡C-) unit that is linked at the 4-position of the NI unit. A series of three oligomers is investigated, OPE1-NI, OPE3-NI, and OPE5-NI, which contain 1, 3, and 5 phenylene ethynylene repeat units, respectively. The properties of the OPEn-NI series are compared to a corresponding set of unsubstituted OPEs, OPE3 and OPE5, which contain 3 and 5 phenylene ethynylene repeats, respectively. The photophysics of all the compounds are interrogated using a variety of techniques including steady-state absorption, steady-state fluorescence, two-photon absorption, time-resolved fluorescence, and transient absorption spectroscopy on femtosecond-to-microsecond time scales. The effect of solvent polarity on the properties of the oligomers is examined. The results show that the NI-substituted oligomers feature a lowest charge transfer (CT) excited state, where the OPE segment acts as the donor and the NI moiety is the acceptor (OPEn•+-NI•-). The absorption spectra in one-photon and two-photon exhibit a clear manifold of absorption features that can be attributed to direct CT absorption. In moderately polar solvents, the emission is dominated by a broad, solvatochromic band that is due to radiative decay from the CT excited state. Ultrafast transient absorption provides evidence for initial population of a locally excited state (LE) which in moderately polar solvents rapidly (∼1 ps) evolves into the CT excited state. The structure, spectroscopy, and dynamics of the CT state are qualitatively similar for OPE3-NI and OPE5-NI, suggesting that delocalization in the OPE segment does not have much effect on the structure or energetics of the CT excited state.

7.
Hum Brain Mapp ; 42(11): 3440-3449, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33830581

RESUMO

The aberrant thalamocortical pathways of epilepsy have been detected recently, while its underlying effects on epilepsy are still not well understood. Exploring pathoglytic changes in two important thalamocortical pathways, that is, the basal ganglia (BG)-thalamocortical and the cerebellum-thalamocortical pathways, in people with idiopathic generalized epilepsy (IGE), could deepen our understanding on the pathological mechanism of this disease. These two pathways were reconstructed and investigated in this study by combining diffusion and functional MRI. Both pathways showed connectivity changes with the perception and cognition systems in patients. Consistent functional connectivity (FC) changes were observed mainly in perception regions, revealing the aberrant integration of sensorimotor and visual information in IGE. The pathway-specific FC alterations in high-order regions give neuroimaging evidence of the neural mechanisms of cognitive impairment and epileptic activities in IGE. Abnormal functional and structural integration of cerebellum, basal ganglia and thalamus could result in an imbalance of inhibition and excitability in brain systems of IGE. This study located the regulated cortical regions of BG and cerebellum which been affected in IGE, established possible links between the neuroimaging findings and epileptic symptoms, and enriched the understanding of the regulatory effects of BG and cerebellum on epilepsy.

8.
ACS Nano ; 15(3): 4979-4988, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33709690

RESUMO

Engineering photosensitizers into stimuli-responsive supramolecular nanodrugs allows enhanced spatiotemporal delivery and controllable release of photosensitizers, which is promising for dedicated and precise tumor photodynamic therapy. Complicated fabrication for nanodrugs with good tumor accumulation capability and the undesirable side-effects caused by the drug components retards the application of PDT in vivo. The fact that extracellular adenosine triphosphate (ATP) is overexpressed in tumor tissue has been overlooked in fabricating nanomedicines for tumor-targeting delivery. Hence, herein we present metal-free helical nanofibers formed in aqueous solution from the coassembly of a cationic porphyrin and ATP as a nanodrug for PDT. The easily accessible and compatible materials and simple preparation enable the nanodrugs with potential in PDT for cancer. Compared to the cationic porphyrin alone, the porphyrin-ATP nanofibers exhibited enhanced tumor-site photosensitizer delivery through whole-body blood circulation. Overexpressed extracellular ATP stabilizes the porphyrin-ATP nanodrug within tumor tissue, giving rise to enhanced uptake of the nanodrug by cancer cells. The enzyme-triggered release of photosensitizers from the nanodrugs upon biodegradation of ATP by intracellular phosphatases results in good tumor therapeutic efficacy. This study demonstrates the potential for employing the tumor microenvironment to aid the accumulation of nanodrugs in tumors, inspiring the fabrication of smart nanomedicines.


Assuntos
Neoplasias , Fotoquimioterapia , Trifosfato de Adenosina , Humanos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Microambiente Tumoral , Água
9.
Brain Struct Funct ; 226(5): 1423-1435, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33730218

RESUMO

This study aims to characterize the connective profiles and the coupling relationship between dynamic and static functional connectivity (dFC and sFC) in large-scale brain networks in patients with generalized epilepsy (GE). Functional, structural and diffuse MRI data were collected from 83 patients with GE and 106 matched healthy controls (HC). Resting-state BOLD time course was deconvolved to neural time course using a blind hemodynamic deconvolution method. Then, five connective profiles, including the structural connectivity (SC) and BOLD/neural time course-derived sFC/dFC networks, were constructed based on the proposed whole brain atlas. Network-level weighted correlation probability (NWCP) were proposed to evaluate the association between dFC and sFC. Both the BOLD signal and neural time course showed highly concordant findings and the present study emphasized the consistent findings between two functional approaches. The patients with GE showed hypervariability and enhancement of FC, and notably decreased SC in the subcortical network. Besides, increased dFC, weaker anatomic links, and complex alterations of sFC were observed in the default mode network of GE. Moreover, significantly increased SC and predominantly increased sFC were found in the frontoparietal network. Remarkably, antagonism between dFC and sFC was observed in large-scale networks in HC, while patients with GE showed significantly decreased antagonism in core epileptic networks. In sum, our study revealed distinct connective profiles in different epileptic networks and provided new clues to the brain network mechanism of epilepsy from the perspective of antagonism between dynamic and static functional connectivity.

10.
J Biosci ; 462021.
Artigo em Inglês | MEDLINE | ID: mdl-33576341

RESUMO

Flower color is the major characteristics and critical breeding program for most Rhododendron species. However, little is known about their coloration mechanism and color inheritance. In this study, petal pigment constituents of three Rhododendron pulchrum Sweet cultivars with different colors were clarified based on LCESI- MS/MS method. Using a broad-targeted metabolomic approach, a total of 149 flavonoids and their glycosylated or methylated derivatives were identified, including 18 anthocyanins (Pg, Cy, Dp, Pn, Pt, and Mv) and 32 flavonols (mainly kaempferol 3-O-glycosides and quercetin 3-O-glycosides). Moreover, anthocyanins were mainly represented by anthocyanidin-3-O-glycosides (glucoside, rutinoside, galactoside, and di-glycosides). Flavone and C-glycosylated flavone were major second metabolites responsible for the difference among three different R. pulchrum cultivars. The accumulation of total flavonoids displayed a clear phenotypic variation: cultivars 'zihe' and 'fenhe' were clustered together, while 'baihe' was clustered alone in the HCA analysis. The composition and content of anthocyanins were more complex in colored flowers ('zehe' and 'fenhe') than in white flower ('baihe'). This study further enhanced our understanding on the flavonoids profile of flower coloration and will provide biochemical basis for further genetic breeding in Rhododendron species.

11.
BMC Anesthesiol ; 21(1): 26, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482737

RESUMO

BACKGROUND: Soluble CD40 ligand (sCD40L) exhibits proinflammatory and procoagulant effects. Recent data indicated that sCD40L plays a significant role in septic patients. The aim of the present study was to determine sCD40L changes in surgical patients without sepsis (SWS) and surgical sepsis patients (SS) during the first 3 days after intensive care unit (ICU) admission and to observe the association between sCD40L and mortality. METHODS: Time changes in sCD40L levels were assessed for 3 days after ICU admission in 49 patients with SS and compared with those in 19 SWS patients. Serum sCD40L concentration was detected by ELISA. Survival at 28 days served as the endpoint. RESULTS: SS had significantly higher sCD40L levels than SWS and control patients. We observed an association between sCD40L levels ≥1028.75 pg/mL at day 2 and 28-day mortality (odds ratio = 7.888; 95% confidence interval = 1.758 to 35.395; P = 0.007). We could not discover any significant differences in sex, presence of septic shock, site of infection, length of stay in the ICU, PaO2/FiO2 ratio, incidence of AKI, ARDS, or type of surgery between nonsurvivors and survivors. CONCLUSIONS: Septic patients show persistently higher circulating sCD40L levels in the first 3 days after ICU admission, and serum sCD40L levels are associated with the mortality of patients with sepsis. Thus, serum sCD40L may be used as a reliable biomarker and therapeutic target in sepsis.

12.
Brain Imaging Behav ; 15(2): 782-787, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32700258

RESUMO

Basal ganglia, which include the striatum and thalamus, have key roles in motivation, emotion, motor function, also contribute to higher-order cognitive function. Previous researches have documented structural and functional alterations in basal ganglia in schizophrenia. While few studies have assessed asymmetries of these characters in basal ganglia of schizophrenia. The current study investigated this issue by using diffusion tensor imaging, anatomic T1-weight image and resting-state functional data from 88 chronic schizophrenic subjects and 92 healthy controls. The structural characteristic, including fractional anisotropy, mean diffusivity (MD) and volume, were extracted and quantified from the subregions of basal ganglia, including caudate, putamen, pallidum and thalamus, through automated atlas-based method. The resting-state functional maps of these regions were also calculated through seed-based functional connectivity. Then, the laterality indexes of structural and functional features were calculated. Compared with healthy controls, schizophrenic subjects showed increased left laterality of volume in striatum and reduced left laterality of volume in thalamus. Furthermore, the difference of laterality of subregions in thalamus is compensatory in schizophrenic subjects. Importantly, the severity of patients' positive symptom was negative corelated with reduced left laterality of volume in thalamus. Our findings provide preliminary evidence demonstrating that the possibility of aberrant laterality in neural pathways and connectivity patterns related to the basal ganglia in schizophrenia.


Assuntos
Esquizofrenia , Anisotropia , Gânglios da Base/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos , Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico por imagem , Tálamo/diagnóstico por imagem
13.
Connect Tissue Res ; 62(3): 337-349, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32180463

RESUMO

Purpose: Reactive oxygen species (ROS) are related to compression stress-induced nucleus pulposus (NP) cell autophagy, but the specific mechanism is unknown in compression stress-induced intervertebral disc degeneration (IVDD). Here, we discuss the specific molecular mechanism and explore whether ROS scavengers could be employed as specific drugs to inhibit compression stress-induced IVDD.Methods: Rat NP cells were exposed to 1.0 MPa compression and pretreatment with the ROS scavenger N-acetylcysteine (NAC) or the JNK-selective inhibitor SP600125 not. Intracellular ROS production was monitored by confocal microscopy. Autophagy was detected by observing the NP cell ultrastructural features using TEM and examining autophagic vacuoles by flow cytometry. The levels of autophagy-associated molecules, the JNK pathway and the PI3K/AKT/mTOR pathway were analyzed by western blotting.Results: Compression-mediated autophagy in rat NP cells was implicated in ROS generation. The ROS scavenger NAC could protect compression-induced NP cell injures by inhibiting ROS production. And SP600125, a JNK inhibitor, attenuated compression-induced NP cell autophagy. Additionally, this is the first report showing that compression induces autophagy in rat NP cells by impeding the compression-induced ROS dependent PI3K/AKT/mTOR pathway and the ROS independent activation of JNK pathway. And the involvement of JNK pathway was in different mechanism of action that when inhibited leaded to increased cell death, increased generation of ROS but decreased autophagy.Conclusions: These results show a new regulatory mechanism involving ROS-mediated autophagy in rat NP cells, which may provide ideas for drug development to improve compression stress-induced IVDD and help avoid eventual surgical treatment of IVD herniation.

14.
Acc Chem Res ; 54(1): 81-91, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33136361

RESUMO

Natural organisms make a wide variety of exquisitely complex, nano-, micro-, and macroscale structured materials in an energy-efficient and highly reproducible manner. During these processes, the information-carrying biomolecules (e.g., proteins, peptides, and carbohydrates) enable (1) hierarchical organization to assemble scaffold materials and execute high-level functions and (2) exquisite control over inorganic materials synthesis, generating biominerals whose properties are optimized for their functions. Inspired by nature, significant efforts have been devoted to developing functional materials that can rival those natural molecules by mimicking in vivo functions using engineered proteins, peptides, DNAs, sequence-defined synthetic molecules (e.g., peptoids), and other biomimetic polymers. Among them, peptoids, a new type of synthetic mimetics of peptides and proteins, have received particular attention because they combine the merits of both synthetic polymers (e.g., high chemical stability and efficient synthesis) and biomolecules (e.g., sequence programmability and biocompatibility). The lack of both chirality and hydrogen bonds in their backbone results in a highly designable peptoid-based system with reduced structural complexity and side chain-chemistry-dominated properties.In this Account, we present our recent efforts in this field by programming amphiphilic peptoid sequences for (1) the controlled self-assembly into different hierarchically structured nanomaterials with favorable properties and (2) manipulating inorganic (nano)crystal nucleation, growth, and assembly into superstructures. First, we designed a series of amphiphilic peptoids with controlled side chain chemistries that self-assembled into 1D highly stiff and dynamic nanotubes, 2D membrane-mimetic nanosheets, hexagonally patterned nanoribbons, and 3D nanoflowers. These crystalline nanostructures exhibited sequence-dependent properties and showed promise for different applications. The corresponding peptoid self-assembly pathways and mechanisms were also investigated by leveraging in situ atomic force microscopy studies and molecular dynamics simulations, which showed precise sequence dependency. Second, inspired by peptide- and protein-controlled formation of hierarchical inorganic nanostructures in nature, we developed peptoid-based biomimetic approaches for controlled synthesis of inorganic materials (e.g., noble metals and calcite), in which we took advantage of the substantial side chain chemistry of peptoids and investigated the relationship between the peptoid sequences and the morphology and growth kinetics of inorganic materials. For example, to overcome the challenges (e.g., complexity of protein- and peptide-folding, poor thermal and chemical stabilities) facing the area of protein- and peptide-controlled synthesis of inorganic materials, we recently reported the design of sequence-defined peptoids for controlled synthesis of highly branched plasmonic gold particles. Moreover, we developed a rule of thumb for designing peptoids that predictively enabled the morphological evolution from spherical to coral-shaped gold nanoparticles (NPs). With this Account, we hope to stimulate the research interest of chemists and materials scientists and promote the predictive synthesis of functional and robust materials through the design of sequence-defined synthetic molecules.

15.
J Hazard Mater ; 407: 124786, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33338814

RESUMO

We prepared and tested carboxymethyl-cellulose-bridged nano-chlorapatite (CMC-CAP) for simultaneous immobilization of Pb, Zn, Cu, and Cd in a field-contaminated acidic soil. Amending the field-contaminated soil using 0.5 wt.% CMC-CAP and 0.1 wt.% CaO was most effective in immobilizing the four metals, which decreased the leachabilities by 98.2%, 98.3%, 96.3%, and 96.2% for Pb, Zn, Cu, and Cd, respectively, after 1 day of treatment. The acid-leached metals fluctuated in the first 60 days, and then approached to steady state after 180 days, where the acid-leachable concentrations all met the regulation levels, and the immobilization was further consolidated when further aged for 365 days. Column elution tests showed that the soil amendment lowered the peak metal concentrations by > 92.5%, and the total eluted masses by >71.9%. Sequential extraction revealed that the soil amendment converted the exchangeable fractions to the much less available Fe-Mn oxides bound and residual forms, and thus, lowered the risk levels to "low risk" for all the metals. The immobilization of the metals was facilitated through formation of stable metal (chloro)phosphates, surface complexation, and/or ion exchange reactions. Combined CMC-CAP and CaO may serve as an effective formulation for simultaneous and long-term immobilization of multiple heavy metals in acidic soil.

16.
Chemosphere ; 263: 128038, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297055

RESUMO

Zinc (Zn2+) and cadmium (Cd2+) in water pose serious threats to human health and the environment. In search for a more effective treatment technology, we prepared a type of carboxymethyl cellulose (CMC) bridged chlorapatite (CMC-CAP) nanoparticles and tested the material for removal of Zn2+ and Cd2+ from water. CMC macromolecules were attached to CAP by bidentate bridging and hydrogen bonding, preserving the high adsorption capacity of CAP nanoparticles while allowing for easy gravity-separation of the nanoparticles. CMC-CAP showed rapid adsorption kinetics and 22.8% and 11.2% higher equilibrium uptake for Zn2+ and Cd2+, respectively, than pristine CAP. An extended dual-mode isotherm model, which takes into account both sorption and chemical precipitation, provided the best fits to the sorption isotherms, giving a maximum Langmuir sorption capacity of 141.1 mg g-1 for Zn2+ and 150.2 mg g-1 for Cd2+ by CMC-CAP. Na+ at up to 5 mM showed modest effects on the uptake of the heavy metals, while 2-5 mM of Ca2+ exerted notable inhibitive effects. Dissolved organic matter (up to 5 mg L-1 as TOC) inhibited the Zn2+ uptake by 16.5% but enhanced the Cd2+ removal by 8.6%. Material characterizations and surface binding analyses revealed that ion exchange, surface precipitation, and surface complexation were the removal mechanisms for the heavy metals. This study demonstrates stabilizer bridging may serve as a convenient strategy to facilitate water treatment uses of nanoparticles.


Assuntos
Metais Pesados , Nanopartículas , Poluentes Químicos da Água , Purificação da Água , Adsorção , Apatitas , Cádmio/análise , Carboximetilcelulose Sódica , Humanos , Água , Poluentes Químicos da Água/análise , Zinco/análise
17.
ACS Appl Mater Interfaces ; 12(47): 53310-53317, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33190474

RESUMO

We report the use of amide coupling chemistry to covalently link five different biofunctional groups onto an anionic water-soluble poly(phenylene ethynylene) (PPE) polymer. Two of the biofunctionalized PPEs are used in prototype applications, including pH sensing and flow cytometry labeling. The PPE is functionalized with carboxylate (R-CO2-) and sulfonate (R-SO3-) ionic groups. By using an activated ester, the amine-functionalized groups are covalently linked to the PPE polymer via amide linkages. The reaction chemistry is optimized using biotin-ethylene diamine, making it possible to control the loading of the biotin functionality on the PPE chains. Using the optimized approach, a family of five PPEs were prepared that contain biotin, rhodamine, cholesterol, mannose, or folic acid moieties appended to the polymer backbones. The rhodamine- and biotin-modified PPEs were further applied for pH response and flow cytometry applications. The reported approach can be utilized for other classes of water-soluble conjugated polymers, allowing facile development of a variety of new functionalized water-soluble conjugated polymers for a range of applications including sensing, bioimaging, and flow cytometry analysis.


Assuntos
Polímeros/química , Água/química , Biotina/química , Colesterol/química , Citometria de Fluxo , Concentração de Íons de Hidrogênio , Manose/química , Solubilidade
18.
Front Hum Neurosci ; 14: 361, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33005141

RESUMO

The present study aims to investigate intrinsic abnormalities of brain and the effect of antiepileptic treatment on brain activity in Benign childhood epilepsy with centrotemporal spikes (BECTS). Twenty-six drug-naïve patients (DNP) and 22 drug-receiving patients (DRP) with BECTS were collected in this study. Static amplitude of low frequency fluctuation (sALFF) and dynamic ALFF (dALFF) were applied to resting-state fMRI data. Functional connectivity (FC) analysis was further performed for affected regions identified by static and dynamic analysis. One-way analysis of variance and post hoc statistical analyses were performed for between-group differences. Abnormal sALFF and dALFF values were correlated with clinical features of patients. Compared with healthy controls (HC), DNP group demonstrated alterations of sALFF and/or dALFF in medial prefrontal cortex (MPFC), supplementary motor areas (SMA), cerebellum, hippocampus, pallidum and cingulate cortex, in which the values were close to normal in DRP. Notably, sALFF and dALFF showed specific sensitivity in detecting abnormalities in basal ganglia and cerebellum. Additionally, DRP showed additional changes in precuneus, inferior temporal gyrus, superior frontal gyrus and occipital visual cortex. Compared with HC, the DNP showed increased FC in default network and motion-related networks, and the DRP showed decreased FC in default network. The MPFC, hippocampus, SMA, basal ganglia and cerebellum are indicated to be intrinsically affected regions and effective therapeutic targets. And the FC profiles of default and motion-related networks might be potential core indicators for clinical treatment. This study revealed potential neuromodulatory targets and helped understand pathomechanism of BECTS. Static and dynamic analyses should be combined to investigate neuropsychiatric disorders.

19.
Medicine (Baltimore) ; 99(22): e20305, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32481400

RESUMO

BACKGROUND: TNF-like cytokine 1A (TL1A) is a subgroup of the tumor necrosis factor superfamily that exerts pleiotropic effects on cell proliferation, inflammation, activation, and differentiation of immune cells. The purpose of the current study is to investigate the clinical significance of TL1A expression in coronary and peripheral blood of patients with acute coronary syndrome (ACS) to determine if TL1A levels can serve as an accurate prognostic indicator. METHODS: A total of 141 patients undergoing coronary angiography were divided into 4 groups: Control (n = 35), Unstable Angina (UA) (n = 35), acute non-ST segment elevation myocardial infarction (NSTEMI) (n = 37), and acute ST segment elevation myocardial infarction (STEMI) (n = 34). The levels of TL1A, MPO, hs-CRP, and IL-10 were detected in coronary and peripheral blood using enzyme linked immunosorbent assay (ELISA), and the MACE incidence rates were compared during 26.3 months of follow-up. RESULTS: TL1A levels were not significantly different between the UA group and control group. In the UA group, TL1A levels were not significantly different between coronary blood and peripheral blood. However, TL1A levels were higher in the STEMI and NSTEMI groups than in the control group (P < .05). Moreover, TL1A levels in the coronary blood of the STEMI and NSTEMI groups were higher than in the peripheral blood (P < .05). The expression of TL1A in the coronary blood was the highest in the STEMI group. In addition, TL1A level in the coronary blood was highly correlated with levels in the peripheral blood (correlation coefficient: 0.899, P < .001). The hs-CRP and MPO levels in the coronary and peripheral blood of all the UA, NSTEMI, and STEMI groups were higher than the control group. Plasma IL-10 levels in all the UA, NSTEMI and STEMI groups were lower than those in the control group. Plasma TL1A level was positively correlated with the cTnI level, degree of coronary thrombus burden, occurrence of slow coronary flow / no coronary reflow and MACE, but negatively correlated with the IL-10 level or non-correlated with the Syntax score. CONCLUSION: Plasma TL1A concentration levels can be used as a predictor of inflammatory response and prognosis in patients with ACS. TRIAL REGISTRATION: ClinicalTrials.gov, number: NCT02430025; Unique Protocol ID: FJPH20150101; Brief Title: Fujian Province Cardiovascular Diseases Study (FJCVD).


Assuntos
Síndrome Coronariana Aguda/sangue , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/biossíntese , Idoso , Angina Instável/sangue , Biomarcadores , Índice de Massa Corporal , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/classificação
20.
Stem Cells Int ; 2020: 7126914, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32399049

RESUMO

Puerarin (PUR), an 8-C-glucoside of daidzein extracted from Pueraria plants, is closely related to autophagy, reduced reactive oxygen species (ROS) production, and anti-inflammatory effects, but its effects on human nucleus pulposus mesenchymal stem cells (NPMSCs) have not yet been identified. In this study, NPMSCs were cultured in a compression apparatus to simulate the microenvironment of the intervertebral disc under controlled pressure (1.0 MPa), and we found that cell viability was decreased and apoptosis level was gradually increased as compression duration was prolonged. After PUR administration, apoptosis level evaluated by flow cytometry and caspase-3 activity was remitted, and protein levels of Bas as well as cleaved caspase-3 were decreased, while elevated Bcl-2 level was identified. Moreover, ATP production detection, ROS, and JC-1 fluorography as well as quantitative analysis suggested that PUR could attenuate intercellular ROS accumulation and mitochondrial dysfunction. Besides, the rat tail compression model was utilized, which indicated that PUR could restore impaired nucleus pulposus degeneration induced by compression. The PI3K/Akt pathway was identified to be deactivated after compression stimulation by western blot, and PUR could rescue the phosphorylation of Akt, thus reactivating the pathway. The effects of PUR, such as antiapoptosis, cell viability restoration, antioxidation, and mitochondrial maintenance, were all counteracted by application of the PI3K/Akt pathway inhibitor (LY294002). Summarily, PUR could alleviate compression-induced apoptosis and cell death of human NPMSCs in vitro as well as on the rat compression model and maintain intracellular homeostasis by stabilizing mitochondrial membrane potential and attenuating ROS accumulation through activating the PI3K/Akt pathway.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...