73 research outputs found
AM-TEPA Impregnated Disordered Mesoporous Silica as CO<sub>2</sub> Capture Adsorbent for Balanced Adsorption–Desorption Properties
A disordered mesoporous silica was found to be a promising
solid
support for CO<sub>2</sub> capture. It was prepared with a process
similar to that for MCM-41. X-ray diffraction characterization (XRD)
and transmission electron microscopy (TEM) confirmed its disordered
structure. N<sub>2</sub> adsorption–desorption tests indicated
that its average pore size is significantly larger than that of MCM-41.
On this support was deposited acrylamide (AM)-modified tetraethylenepentamine
(TEPA), resulting in an adsorbent suitable for CO<sub>2</sub> capture.
This material exhibited well balanced adsorption and desorption properties.
Substantially higher CO<sub>2</sub> adsorption capacity (159.1 mg/g-adsorbent)
was obtained with pure CO<sub>2</sub> at 25 °C, and satisfactory
stability during 12 adsorption–desorption turnovers was achieved
Investigations of FAK inhibitors: a combination of 3D-QSAR, docking, and molecular dynamics simulations studies
<p>Focal adhesion kinase (FAK) is one kind of tyrosine kinases that modulates integrin and growth factor signaling pathways, which is a promising therapeutic target because of involving in cancer cell migration, proliferation, and survival. To investigate the mechanism between FAK and triazinic inhibitors and design high activity inhibitors, a molecular modeling integrated with 3D-QSAR, molecular docking, molecular dynamics simulations, and binding free energy calculations was performed. The optimum CoMFA and CoMSIA models showed good reliability and satisfactory predictability (with <i>Q</i><sup>2</sup>Â =Â 0.663, <i>R</i><sup>2</sup>Â =Â 0.987, Â =Â 0.921 and <i>Q</i><sup>2</sup>Â =Â 0.670, <i>R</i><sup>2</sup>Â =Â 0.981, Â =Â 0.953). Its contour maps could provide structural features to improve inhibitory activity. Furthermore, a good consistency between contour maps, docking, and molecular dynamics simulations strongly demonstrates that the molecular modeling is reliable. Based on it, we designed several new compounds and their inhibitory activities were validated by the molecular models. We expect our studies could bring new ideas to promote the development of novel inhibitors with higher inhibitory activity for FAK.</p
Copper-Catalyzed Double C–S Bonds Formation <i>via</i> Different Paths: Synthesis of Benzothiazoles from <i>N</i>‑Benzyl-2-iodoaniline and Potassium Sulfide
A new,
highly efficient procedure for the synthesis of benzothiazoles
from easily available <i>N</i>-benzyl-2-iodoaniline and
potassium sulfide has been developed. The results show copper-catalyzed
double C–S bond formation via a traditional cross-coupling
reaction and an oxidative cross-coupling reaction
Corrosion Inhibition of N80 Steel Using Novel Diquaternary Ammonium Salts in 15% Hydrochloric Acid
Three novel diquaternary ammonium
salts with alkanediyl spacers of varying chain length were synthesized,
and their corrosion inhibition effects on N80 steel in 15 wt % HCl
solution were studied by weight loss measurement, electrochemical
polarization, electrochemical impedance spectroscopy (EIS), scanning
electron microscope (SEM), and energy dispersive X-ray spectroscopy
(EDX). The results indicated that the inhibition efficiency increased
with the inhibitor concentration and the length of hydrophobic spacer
of the inhibitor. At 90 °C, the inhibition efficiency of diquaternary
ammonium salt N,N′-octane-1,8-diyl-bisquinolinium dibromide
reached about 91% at the inhibitor concentration of 0.01 mol/L. Potentiodynamic
polarization curves indicated that all synthesized compounds acted
as mixed-type inhibitors. The inhibition mechanism involved the formation
of an inhibitor protective layer on the N80 steel surface by a Langmuir-type
adsorption process. The presence of Br and N in chemical composition
detected by EDX confirmed the adsorption of inhibitors on the N80
steel surface
New putative cryptic species detection and genetic network analysis of <i>Bemisia tabaci</i> (Hempitera: Aleyrodidae) in China based on mitochondrial COI sequences
<p>The whitefly <i>Bemisia tabaci</i> (Gennadius) (Hemiptera: Aleyrodidae) is a cryptic species complex and widely distributed throughout tropical and subtropical regions. To understand the <i>B. tabaci</i> cryptic species diversity in China more comprehensively, in the year 2014 and 2016, a large-scale sampling was conducted from the famous biodiversity hotspot of China, Yunnan province. Mitochondrial cytochrome oxidase I gene sequences were used to identify new putative cryptic species. Phylogenetic analyses were performed using Bayesian methods to evaluate the position of new cryptic species in the context of the <i>B. tabaci</i> diversity in Asia. Two new cryptic species, China 5 and Asia V were identified. In total, 19 <i>B. tabaci</i> cryptic species are present in China, two invasive (MED and MEAM1) and 17 indigenous. A new sibling species of <i>B. tabaci</i> was first defined and reported. Based on the mtCOI sequences and haplotype network analyses, the genetic diversity of MED was far higher than MEAM1. We confirmed the exotic MED was originated from the western Mediterranean regions and first invaded into Yunnan, China. The genetic structures of other four indigenous species (Asia I, Asia II 1, Asia II 6, and China 1) with relatively wide distribution ranges in China were also discussed.</p
Data_Sheet_2_The prevalence and risk factors of anxiety in multiple sclerosis: A systematic review and meta-analysis.pdf
BackgroundPatients with multiple sclerosis (MS) suffer from repetitive neurological deterioration, while anxiety may play a significant role in the disease’s progression.ObjectiveTo explore the prevalence of anxiety in MS and to investigate the risk factors related to anxiety in MS patients.MethodsAn analysis of four databases, PubMed, Web of Science, EMBASE, and Cochrane Library, has been conducted to determine the prevalence or risk factors for anxiety in MS published before May 2021.ResultsIn total, 32 studies were found to be eligible. Anxiety prevalence was estimated to be 36% based on the pooled estimates [the 95% confidence interval (CI) = [0.30–0.42], I2 = 98.4%]. Significant risk factors for developing of anxiety were as follows: age at survey [the weighted mean difference (WMD) = 0.96, 95% CI = [0.86–1.06], I2 = 43.8%], female [the odd ratio (OR) = 1.78, 95% CI = [1.38–2.30], I2 = 0%], living together (OR 2.83, 95% CI = [1.74–4.59], I2 = 0%), past psychiatric history (OR 2.42, 95% CI = [1.56–3.75], I2 = 0%), depression (OR 7.89, 95% CI = [3.71–16.81], I2 = 0%), not taking MS medication (OR 2.33, 95% CI = [1.29–4.21], I2 = 77.8%), relapsing-remitting MS (RRMS) (OR 1.50, 95% CI = [0.94–2.37], I2 = 53.5%), and baseline Expanded Disability Status Scale (EDSS) (OR 0.84, 95% CI = [0.48–1.21], I2 = 62.2%).ConclusionAn estimated 36% of people with MS suffer from anxiety. And anxiety rates in MS patients are significantly associated with age, gender, living together, prior psychiatric history, depression, drug compliance, RRMS, and baseline EDSS.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=287069, identifier CRD42021287069.</p
Data_Sheet_1_The prevalence and risk factors of anxiety in multiple sclerosis: A systematic review and meta-analysis.pdf
BackgroundPatients with multiple sclerosis (MS) suffer from repetitive neurological deterioration, while anxiety may play a significant role in the disease’s progression.ObjectiveTo explore the prevalence of anxiety in MS and to investigate the risk factors related to anxiety in MS patients.MethodsAn analysis of four databases, PubMed, Web of Science, EMBASE, and Cochrane Library, has been conducted to determine the prevalence or risk factors for anxiety in MS published before May 2021.ResultsIn total, 32 studies were found to be eligible. Anxiety prevalence was estimated to be 36% based on the pooled estimates [the 95% confidence interval (CI) = [0.30–0.42], I2 = 98.4%]. Significant risk factors for developing of anxiety were as follows: age at survey [the weighted mean difference (WMD) = 0.96, 95% CI = [0.86–1.06], I2 = 43.8%], female [the odd ratio (OR) = 1.78, 95% CI = [1.38–2.30], I2 = 0%], living together (OR 2.83, 95% CI = [1.74–4.59], I2 = 0%), past psychiatric history (OR 2.42, 95% CI = [1.56–3.75], I2 = 0%), depression (OR 7.89, 95% CI = [3.71–16.81], I2 = 0%), not taking MS medication (OR 2.33, 95% CI = [1.29–4.21], I2 = 77.8%), relapsing-remitting MS (RRMS) (OR 1.50, 95% CI = [0.94–2.37], I2 = 53.5%), and baseline Expanded Disability Status Scale (EDSS) (OR 0.84, 95% CI = [0.48–1.21], I2 = 62.2%).ConclusionAn estimated 36% of people with MS suffer from anxiety. And anxiety rates in MS patients are significantly associated with age, gender, living together, prior psychiatric history, depression, drug compliance, RRMS, and baseline EDSS.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=287069, identifier CRD42021287069.</p
Actin Stabilization by Jasplakinolide Affects the Function of Bone Marrow-Derived Late Endothelial Progenitor Cells
<div><h3>Background</h3><p>Bone marrow-derived endothelial progenitor cells (EPCs), especially late EPCs, play a critical role in endothelial maintenance and repair, and postnatal vasculogenesis. Although the actin cytoskeleton has been considered as a modulator that controls the function and modulation of stem cells, its role in the function of EPCs, and in particular late EPCs, remains poorly understood.</p> <h3>Methodology/Principal Finding</h3><p>Bone marrow-derived late EPCs were treated with jasplakinolide, a compound that stabilizes actin filaments. Cell apoptosis, proliferation, adhesion, migration, tube formation, nitric oxide (NO) production and endothelial NO synthase (eNOS) phosphorylation were subsequently assayed in vitro. Moreover, EPCs were locally infused into freshly balloon-injured carotid arteries, and the reendothelialization capacity was evaluated after 14 days. Jasplakinolide affected the actin distribution of late EPCs in a concentration and time dependent manner, and a moderate concentration of (100 nmol/l) jasplakinolide directly stabilized the actin filament of late EPCs. Actin stabilization by jasplakinolide enhanced the late EPC apoptosis induced by VEGF deprivation, and significantly impaired late EPC proliferation, adhesion, migration and tube formation. Furthermore, jasplakinolide attenuated the reendothelialization capacity of transplanted EPCs in the injured arterial segment in vivo. However, eNOS phosphorylation and NO production were increased in late EPCs treated with jasplakinolide. NO donor sodium nitroprusside (SNP) rescued the functional activities of jasplakinolide-stressed late EPCs while the endothelial NO synthase inhibitor L-NAME led to a further dysfunction induced by jasplakinolide in late EPCs.</p> <h3>Conclusions/Significance</h3><p>A moderate concentration of jasplakinolide results in an accumulation of actin filaments, enhancing the apoptosis induced by cytokine deprivation, and impairing the proliferation and function of late EPCs both in vitro and in vivo. NO donor reverses these impairments, suggesting the role of NO-related mechanisms in jasplakinolide-induced EPC downregulation. Actin cytoskeleton may thus play a pivotal role in regulating late EPC function.</p> </div
Second Generation TQ-Ligation for Cell Organelle Imaging
Bioorthogonal ligations
play a crucial role in labeling diverse
types of biomolecules in living systems. Herein, we describe a novel
class of <i>ortho</i>-quinolinone quinone methide (<i>o</i>QQM) precursors that show a faster kinetic rate in the
“click cycloaddition” with thio-vinyl ether (TV) than
the first generation TQ-ligation in both chemical and biological settings.
We further demonstrate that the second generation TQ-ligation is also
orthogonal to the widely used strain-promoted azide–alkyne
cycloaddition (SPAAC) both <i>in vitro</i> and <i>in
vivo</i>, revealing that these two types of bioorthogonal ligations
could be used as an ideal reaction pair for the simultaneous tracking
of multiple elements within a single system. Remarkably, the second
generation TQ-ligation and SPAAC are effective for selective and simultaneous
imaging of two different cell organelles in live cells
Jasplakinolide inhibited the adhesion of late EPCs.
<p>(A) Late EPCs were pretreated with either jasplakinolide or DMSO for 1 h and then seeded on either plastic or culture surfaces coated with different ECM proteins, such as fibronectin, collagen I or laminin, and incubated for 1 h at 37°C. After nonadherent cells were removed by washing, adherent cells were counted and analyzed. (B) The cell surface expressions of integrin β1 and β3 were assessed by FACS. Representative FACS profiles of four independent experiments are shown. The relative fluorescence intensity that is normalized with the mean fluorescence intensity of isotype control. Data represent the mean±SE of four different experiments. **P<0.01.</p
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