20 research outputs found
Evaluation and Comparison of Choroidal Thickness in Patients with Behçet Disease with versus without Ocular Involvement
Purpose: To assess the subfoveal choroidal thickness (SFCT) in patients with Behçet disease (BD) and compare the SFCT in patients with and without ocular BD (OBD) and between patients with active and quiescent phases of the Behçet’s posterior uveitis.
Method: This prospective cross-sectional study was conducted on patients with BD (n = 51) between October 2016 and October 2018. Complete ocular examinations including slit lamp biomicroscopy and fundus examination with dilated pupils were performed for all patients. The SFCT values were compared between patients with and without OBD. Enhanced depth imaging optical coherence tomography (EDI–OCT) was done to measure the SFCT, and wide field fundus fluorescein angiography (WF–FAG) was performed to evaluate the ocular involvement and determine the active or quiescent phases of the Behçet’s posterior uveitis. The correlation between the changes of SFCT and the WF-FAG scores was assessed.
Results: One hundred and two eyes of 51 patients with BD, aged 29 to 52 years were studied. Of these, 23 patients were male. The mean age ± standard deviation in patients with OBD and patients without ocular involvement was 38.71 ± 7.8 and 36.22 ± 10.59 years (P = 0.259) respectively. The mean SFCT in patients with OBD was significantly greater than in patients without OBD (364.17 ± 93.34 vs 320.43 ± 56.70 μm; P = 0.008). The difference of mean SFCT between the active compared to quiescent phase was not statistically significant when only WF-FAG criteria were considered for activity (368.12 ± 104.591 vs 354.57 ± 58.701 μm, P = 0.579). However, when the disease activity was considered based on both WF-FAG and ocular exam findings, SFCT in the active group was higher than the inactive group (393.04 ± 94.88 vs 351.65 ± 58.63 μm, P = 0.060). This difference did not reach statistical significance, but it was clinically relevant.
Conclusion: Choroidal thickness was significantly increased in BD patients with ocular involvement; therefore, EDI-OCT could be a noninvasive test for evaluation of ocular involvement in patients with BD. The increased SFCT was not an indicative of activity in OBD; however, it could predict possible ocular involvement throughout the disease course
Heterogeneous catalysts with programmable topologies generated by reticulation of organocatalysts into metal-organic frameworks : The case of squaramide
A well-established strategy to synthesize heterogeneous, metal-organic framework (MOF) catalysts that exhibit nanoconfinement effects, and specific pores with highly-localized catalytic sites, is to use organic linkers containing organocatalytic centers. Here, we report that by combining this linker approach with reticular chemistry, and exploiting three-dimensioanl (3D) MOF-structural data from the Cambridge Structural Database, we have designed four heterogeneous MOF-based catalysts for standard organic transformations. These programmable MOFs are isoreticular versions of pcu IRMOF-16, fcu UiO-68 and pillared-pcu SNU-8X, the three most common topologies of MOFs built from the organic linker p,p'-terphenyldicarboxylic acid (tpdc). To synthesize the four squaramide-based MOFs, we designed and synthesized a linker, 4,4'-((3,4-dioxocyclobut-1-ene-1,2-diyl)bis(azanedyil))dibenzoic acid (Sq_tpdc), which is identical in directionality and length to tpdc but which contains organocatalytic squaramide centers. Squaramides were chosen because their immobilization into a framework enhances its reactivity and stability while avoiding any self-quenching phenomena. Therefore, the four MOFs share the same organocatalytic squaramide moiety, but confine it within distinct pore environments. We then evaluated these MOFs as heterogeneous H-bonding catalysts in organic transformations: a Friedel-Crafts alkylation and an epoxide ring-opening. Some of them exhibited good performance in both reactions but all showed distinct catalytic profiles that reflect their structural differences
An Improved SIW Leaky Wave Antenna Based on a Compact CRLH Unit Cell
In this paper, a new composite right/left-handed (CRLH) Leaky Wave Antenna
(LWA) based on substrate-integrated waveguide (SIW) structures is proposed. The
suggested antenna has a continuous beam scanning from backward to forward
versus frequency and can be used for wideband applications. The compact
composite right/left-handed (C-CRLH) unit cell for the mentioned antenna is
designed by etching two transverse slots and one interdigital slot between them
on the upper ground plate of the SIW structure. The C-CRLH unit cell dispersion
diagram extracted from the simulation results is compared with the transmission
line approach results. The CRLH band is from 12GHz to 24GHz, and the antenna
operation frequency band is from 13GHz to 22GHz. The beam scanning angle of the
proposed antenna is from to . The maximum radiation
efficiency is 91.89% and more than 85.7% in 13GHz-19.5GHz. It is worth noting
that the maximum gain of the antenna is 12.66dBi, and it is approximately 12
dBi in 13GHz-20GHz. The measurement results of the antenna are compared with
simulation results, and a good agreement is observed.Comment: 7 pages, 13 figure
An improved solvent-free synthesis of flunixin and 2-(arylamino) nicotinic acid derivatives using boric acid as catalyst
Abstract A simple solvent-free protocol for the preparation of flunixin, a potent non-narcotic, non-steroidal anti-inflammatory drugs is reported using boric acid as catalyst. Its salt, flunixin meglumine are then prepared under reflux in EtOH. This sustainable method are then extended for the synthesis of a series of 2-(arylamino) nicotinic acid derivatives. The present protocol combines non-hazardous neat conditions with associated benefits like excellent yield, straightforward workup, and use of readily available and safe catalyst in the absence of any solvent, which are important factors in the pharmaceutical industry. The pathway for catalytic activation of 2-chloronicotic acid with boric acid was also investigated using Gaussian 03 program package
Ultrasonic-Assisted Preparation, Characterization, and Use of Novel Biocompatible Core/Shell Fe3O4@GA@Isinglass in the Synthesis of 1,4-Dihydropyridine and 4H‑Pyran Derivatives
Magnetic core–shell Carrageenan moss/Fe3O4: a polysaccharide-based metallic nanoparticles for synthesis of pyrimidinone derivatives via Biginelli reaction
Abstract Magnetically recoverable polysaccharide-based metallic nanoparticles Carrageenan moss/Fe3O4 (Fe3O4@CM) was tested for the synthesis of Pyrimidinone derivatives via Biginelli reaction under reflux conditions in Water. Interestingly, Fe3O4@CM prepared from unmodified Irish moss showed remarkable catalytic activity and recyclability. Low catalyst loading, simple reaction procedure, and using a green catalyst from a natural source are the important merits of this protocol
Synthesis, Molecular Docking, Molecular Dynamics Studies, and Biological Evaluation of 4H-Chromone-1,2,3,4-tetrahydropyrimidine-5-carboxylate Derivatives as Potential Antileukemic Agents
A series of 4H-chromone-1,2,3,4-tetrahydropyrimidine-5-carboxylates derivatives were synthesized via a three component one-pot condensation of chromone-3-carbaldehyde, alkyl acetoacetate, and urea or thiourea, using MCM-41-SO3H as efficient nanocatalysts and evaluated for their anticancer activity using a combined in silico docking and molecular dynamics protocol to estimate the binding affinity of the title compounds with the Bcr-Abl oncogene. Two programs, AutoDock 4 and AutoDock Vina software were applied to dock the target protein with synthesized compounds and ATP. AutoDock runs resulted in binding energy scores from -7.8 to -10.16 kcal/mol for AutoDock 4 and -6.9 to -8.5 (kcal/mol) for AutoDock Vina. Furthermore, molecular dynamics (MD) simulations are performed using Gromacs for up to 20 ns simulation time investigating the stability of a ligand-protein complex. Finally, a theoretical experiment using MD simulation for 10 ns was performed without defining the initial coordinates, and the affinity binding of ligand to receptors was directly studied, which revealed that the ligand approaches the active sites. The relative free binding energy for the structure 06 (S06), which has the highest binding energy in Autodock 4 and Autodock Vina (-10.10 and -8.5 kcal/mol, respectively), was also evaluated by molecular mechanics (MM) with Poisson-Boltzmann (PB) and a surface area solvation (MM-PBSA) method using g_mmpbsa tools for the last 15 ns MD. On the basis of binding energy scores, a negative binding energy value of 73.6 kcal/mol, S06, was recognized as the dominant potential inhibitors. The cytotoxic properties of S06 was evaluated against three cell lines, acute T cell leukemia (Jurkat), human chronic myelogenous leukemia, (K562) and human foreskin fibroblast (Hu02) using the microculture tetrazolium test MTT assay. Cisplatin was used as the reference agent. The results indicated that S06 has a higher safety index (SI = 0.73, IC50 = 152.64 μg/mL for Jurkat and IC50 = 110.25 μg/mL for Hu02, P < 0.05 means ± SD for four independent experiments) compared to cisplatin (SI = 0.56, IC50 = 8.86 μg/mL for Jurkat and IC50 = 4.96 μg/mL for Hu02). The in silico results indicated that the proposed structures, which have no toxic effects, are potential tyrosine kinase inhibitors (TKIs) that target Bcr-Abl and thus prevent uncontrolled cell growth (proliferation) but not necessarily cell death (apoptosis) and might potentially constitute an interesting novel class of targeted antileukemic drugs, which deserve further studies
MOESM1 of An improved solvent-free synthesis of flunixin and 2-(arylamino) nicotinic acid derivatives using boric acid as catalyst
Additional file 1. Supporting Information
Ultrasonic-Assisted Preparation, Characterization, and Use of Novel Biocompatible Core/Shell Fe<sub>3</sub>O<sub>4</sub>@GA@Isinglass in the Synthesis of 1,4-Dihydropyridine and 4<i>H</i>‑Pyran Derivatives
This work focussed on the synthesis of a new catalytic material
isinglass (IG)-based Fe<sub>3</sub>O<sub>4</sub>@GA@IG core/shell
magnetic nanoparticles and the investigation of its catalytic activity
in two important multicomponent reactions. Fe<sub>3</sub>O<sub>4</sub> nanoparticles were prepared using a simple coprecipitation method
and then coated with IG consisting predominantly of the protein collagen
in the presence of glutaraldehyde as a cross-linking agent. The obtained
hybrid material has been characterized by Fourier transform infrared
analysis, scanning electron microscopy, transmission electron microscopy
(TEM), vibrating sample magnetometry, energy-dispersive X-ray, X-ray
diffraction (XRD), and Brunauer–Emmett–Teller analyses.
The results of XRD analysis implied that the prepared nanocomposite
consists of two compounds of crystalline magnetite and amorphous IG,
and the formation of its core/shell structure had been confirmed by
TEM images. The catalytic performance of the as-prepared core/shell
bionanocatalyst was evaluated for the first time in the synthesis
of 1,4-dihydropyridine and 4<i>H</i>-pyran derivatives under
sonication in ethanol. This core/shell structure because of the superparamagnetic
property of Fe<sub>3</sub>O<sub>4</sub> and unique properties of IG
as a bifunctional biocatalyst offers a high potential for many catalytic
applications. Recycling study revealed that no significant decrease
in the catalytic activity was observed even after six runs
Synthesis, Molecular Docking, Molecular Dynamics Studies, and Biological Evaluation of 4<i>H</i>‑Chromone-1,2,3,4-tetrahydropyrimidine-5-carboxylate Derivatives as Potential Antileukemic Agents
A series of 4<i>H</i>-chromone-1,2,3,4-tetrahydropyrimidine-5-carboxylates derivatives
were synthesized via a three component one-pot condensation of chromone-3-carbaldehyde,
alkyl acetoacetate, and urea or thiourea, using MCM-41-SO<sub>3</sub>H as efficient nanocatalysts and evaluated for their anticancer activity
using a combined in silico docking and molecular dynamics protocol
to estimate the binding affinity of the title compounds with the Bcr-Abl
oncogene. Two programs, AutoDock 4 and AutoDock Vina software were
applied to dock the target protein with synthesized compounds and
ATP. AutoDock runs resulted in binding energy scores from −7.8
to −10.16 kcal/mol for AutoDock 4 and −6.9 to −8.5
(kcal/mol) for AutoDock Vina. Furthermore, molecular dynamics (MD)
simulations are performed using Gromacs for up to 20 ns simulation
time investigating the stability of a ligand–protein complex.
Finally, a theoretical experiment using MD simulation for 10 ns was
performed without defining the initial coordinates, and the affinity
binding of ligand to receptors was directly studied, which revealed
that the ligand approaches the active sites. The relative free binding
energy for the structure 06 (<b>S06</b>), which has the highest
binding energy in Autodock 4 and Autodock Vina (−10.10 and
−8.5 kcal/mol, respectively), was also evaluated by molecular
mechanics (MM) with Poisson–Boltzmann (PB) and a surface area
solvation (MM-PBSA) method using g_mmpbsa tools for the last 15 ns
MD. On the basis of binding energy scores, a negative binding energy
value of 73.6 kcal/mol, <b>S06</b>, was recognized as the dominant
potential inhibitors. The cytotoxic properties of <b>S06</b> was evaluated against three cell lines, acute T cell leukemia (Jurkat),
human chronic myelogenous leukemia, (K562) and human foreskin fibroblast
(Hu02) using the microculture tetrazolium test MTT assay. Cisplatin
was used as the reference agent. The results indicated that <b>S06</b> has a higher safety index (SI = 0.73, IC50 = 152.64 μg/mL
for Jurkat and IC50 = 110.25 μg/mL for Hu02, <i>P</i> < 0.05 means ± SD for four independent experiments) compared
to cisplatin (SI = 0.56, IC50 = 8.86 μg/mL for Jurkat and IC50
= 4.96 μg/mL for Hu02). The <i>in silico</i> results
indicated that the proposed structures, which have no toxic effects,
are potential tyrosine kinase inhibitors (TKIs) that target Bcr-Abl
and thus prevent uncontrolled cell growth (proliferation) but not
necessarily cell death (apoptosis) and might potentially constitute
an interesting novel class of targeted antileukemic drugs, which deserve
further studies