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1.
Food Chem ; 399: 133948, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35994855

RESUMO

M. oleifera known as "miracle tree" is increasingly used in nutraceuticals for the reported health effects and nutritional value of its leaves. This study presents the first metabolome profiling of M. oleifera leaves of African origin using different solvent polarities via HR-UPLC/MS based molecular networking followed by multivariate data analyses for samples classification. 119 Chemicals were characterized in both positive and negative modes belonging to 8 classes viz. phenolic acids, flavonoids, peptides, fatty acids/amides, sulfolipids, glucosinolates and carotenoids. New metabolites i.e., polyphenolics, fatty acids, in addition to a new class of sulfolipids were annotated for the first time in Moringa leaves. In vitro anti-inflammatory and anti-aging bioassays of the leaf extracts were assessed and in correlation to their metabolite profile via multivariate data analyses. Kaempferol, quercetin and apigenin-O/C-glycosides, fatty acyl amides and carotenoids appeared crucial for biological activities and leaves origin discrimination.


Assuntos
Moringa oleifera , Amidas , Carotenoides/metabolismo , Quimiometria , Ácidos Graxos , Metaboloma , Moringa oleifera/química , Extratos Vegetais/química , Folhas de Planta/química
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 2): 122093, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36375289

RESUMO

In this study, we investigate the abscopal effect induced in the brain, lung and kidney as a result of partial irradiation of experimental animals with 2 Gy γ-rays. Modifications in the protein secondary structure were used as indicator for the abscopal effect. FTIR spectroscopy and analysis of the amide I and amide II absorption bands suggested possible modifications in the protein secondary structure in the brain and kidney following irradiation. Significant shift in the amide I band was recorded only in the brain. However, the amide I/amide II band area ratio for the three organs examined varied differentially in the irradiated groups as compared with the sham-irradiated group. Employing the lorentzian model to analyze the amide I band of the FTIR spectra, we dissected the amide I band into its components, each component represents one form of the protein secondary structure. Calculation of the weight percentage contribution of each of the protein secondary structure revealed decrease in the α-helix contribution associated with equivalent increase in ß-sheets and turns/random coils contributions in the brain and kidney, however the response was more evident in the brain. No change in the α-helix or ß-sheets contributions was reported in the lung following irradiation. The data suggest the induction of abscopal effect in the brain and kidney rather than the lung in the form of protein conformation modification. The data also indicate that the abscopal effect is comparable to the effect of direct irradiation in both of the brain and kidney.


Assuntos
Amidas , Proteínas , Animais , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Conformação Proteica , Amidas/química
3.
Methods Mol Biol ; 2602: 107-122, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36446970

RESUMO

The family of ubiquitin C-terminal hydrolases (UCHs(releases ε-linked amide bonds positioned at the C-terminus of ubiquitin. UCHL3 is a highly conserved and dual functional member of this family, recognizing C-terminal extensions of two paralogous modifiers: ubiquitin and NEDD8. The Saccharomyces cerevisiae orthologue of UCHL3, namely, Yuh1, is the only UCH family member in this organism. Like UCHL3, Yuh1 recognizes ubiquitin as well as Rub1, the direct orthologue of NEDD8 in S. cerevisiae. We describe here a method for examining the activity of bacteria and yeast expressed Yuh1 by monitoring the C-terminal trimming of UBB + 1 and Rub1 + 1 through immunoblotting and the increased AMC fluorescence readout detected through a plate reader.


Assuntos
Proteínas de Saccharomyces cerevisiae , Ubiquitina Tiolesterase , Saccharomyces cerevisiae/genética , Proteólise , Ubiquitina , Amidas , Ubiquitinas
4.
Sci Total Environ ; 858(Pt 2): 159922, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336064

RESUMO

Nanofiltration (NF) membranes have been widely used in various fields including water treatment and other separation processes, while conventional thin film composite (TFC) membranes with polyamide (PA) selective layers suffer the problems of fouling and chlorine intolerance. Due to the abundant hydrophilic hydroxyl groups and ester bonds free from chlorine attack, the TFC membranes composed of polyester (PE) or polyester-amide (PEA) selective layers have been proven to possess enhanced anti-fouling properties and superior chlorine resistance. In this review, the research progress of PE and PEA nanofiltration membranes is systematically summarized according to the variety of hydroxyl-containing monomers for membrane fabrication by the interfacial polymerization (IP) reaction. The synthesis strategies as well as the mechanisms for tailoring properties and performance of PE and PEA membranes are analyzed, and the membrane application advantages are demonstrated. Moreover, current challenges and future perspectives of the development of PE and PEA nanofiltration membranes are proposed. This review can offer guidance for designing high-performance PE and PEA membranes, thereby further promoting the efficacy of nanofiltration.


Assuntos
Cloro , Membranas Artificiais , Poliésteres , Amidas , Permeabilidade
5.
Magn Reson Med ; 89(2): 636-651, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36198015

RESUMO

PURPOSE: Nuclear Overhauser enhancement (NOE)-mediated CEST imaging at -3.5 ppm has shown clinical interest in diagnosing tumors. Multiple-pool Lorentzian fit has been used to quantify NOE, which, however, requires a long scan time. Asymmetric analysis of CEST signals could be a simple and fast method to quantify this NOE, but it has contamination from the amide proton transfer (APT) at 3.5 ppm. This work proposes a new method using an asymmetric analysis of a low-duty-cycle pulsed-CEST sequence with a flip angle of 360°, termed 2π-CEST, to reduce the contribution from APT. METHODS: Simulations were used to evaluate the capability of the 2π-CEST to reduce APT. Experiments on animal tumor models were performed to show its advantages compared with the conventional asymmetric analysis. Samples of reconstituted phospholipids and proteins were used to evaluate the molecular origin of this NOE. RESULTS: The 2π-CEST has reduced contribution from APT. In tumors where we show that the NOE is comparable to the APT effect, reducing the contamination from APT is crucial. The results show that the NOE signal obtained with 2π-CEST in tumor regions appears more homogeneous than that obtained with the conventional method. The phantom study showed that both phospholipids and proteins contribute to the NOE at -3.5 ppm. CONCLUSION: The NOE at -3.5 ppm has a different contrast mechanism from APT and other CEST/NOE effects. The proposed 2π-CEST is more accurate than the conventional asymmetric analysis in detecting NOE, and requires much less scan time than the multiple-pool Lorentzian fit.


Assuntos
Neoplasias Encefálicas , Animais , Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Prótons , Amidas/metabolismo , Fosfolipídeos
6.
Magn Reson Med ; 89(2): 620-635, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36253943

RESUMO

PURPOSE: Design an efficient CEST scheme for exchange-dependent images with high contrast-to-noise ratio. THEORY: Reassembled saturation transfer (REST) signals were defined as Δ $$ \Delta $$ r.Z = r.Zref - r.ZCEST and the reassembled exchange-dependen magnetization transfer ratio r.MTRRex  = r.1/Zref - r.1/ZCEST , utilizing the averages over loosely sampled reference frequency offsets as Zref and over densely sampled target offsets as ZCEST . Using r.MTRRex measured under 2 B1,sat values, exchange rate could be estimated. METHODS: The REST approach was optimized and assessed quantitatively by simulations for various exchange rates, pool concentration, and water T1 . In vivo evaluation was performed on ischemic rat brains at 7 Tesla and human brains at 3 Tesla, in comparison with conventional asymmetrical analysis, Lorentzian difference (LD), an MTRRex_ LD. RESULTS: For a broad choice of Δ ω ref $$ \Delta {\omega}_{ref} $$ ranges and numbers, Δr.Z and r.MTRRex exhibited comparable quantification features with conventional LD and MTRRex _LD, respectively, when B1,sat  ≤ 1 µT. The subtraction of 2 REST values under distinct B1,sat values showed linear relationships with exchange rate and obtained immunity to field inhomogeneity and variation in MT and water T1 . For both rat and human studies, REST images exhibited similar contrast distribution to MTRRex _LD, with superiority in contrast-to-noise ratio and acquisition efficiency. Compared with MTRRex _LD, 2-B1,sat subtraction REST images displayed better resistance to B1 inhomogeneity, with more specific enhanced regions. They also showed higher signals for amide than for nuclear Overhauser enhancement effect in human brain, presumably reflecting the higher increment from faster-exchanging species as B1,sat increased. CONCLUSION: Featuring high contrast-to-noise ratio efficiency, REST could be a practical exchange-dependent approach readily applicable to either retrospective Z-spectra analysis or perspective 6-offset acquisition.


Assuntos
Amidas , Imageamento por Ressonância Magnética , Animais , Humanos , Ratos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade , Encéfalo/diagnóstico por imagem , Água
7.
Magn Reson Med ; 89(2): 565-576, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36300851

RESUMO

PURPOSE: The average saturation efficiency filter (ASEF) is a novel method of improving the specificity of CEST; however, there is a mismatch between the magnetization transfer (MT) effect under high-duty cycle and low-duty cycle pulse trains. We explore measures of mitigation and the sensitivity and potential of ASEF imaging in phantoms and stroke rats. METHODS: Simulation and nicotinamide phantoms in denatured protein were used to investigate the effect of different average saturation powers and MT pool parameters on matching coefficients used for correction as well as the ASEF ratio signal and baseline. Then, in vivo studies were performed in stroke rodents to further investigate the sensitivity and fidelity of ASEF ratio spectra. RESULTS: Simulation and studies of nicotinamide phantoms show that the matching coefficient needed to correct the baseline MT mismatch is strongly dependent on the average saturation power. In vivo studies in stroke rodents show that the matching coefficient required to correct the baseline MT mismatch is different for normal versus ischemic tissue. Thus, a baseline correction was performed to further suppress the residue MT mismatch. After correction of the mismatch, ASEF ratio achieved comparable contrast at 3.6 ppm between normal and ischemic tissue when compared to the apparent amide proton transfer (APT*) approach. Moreover, contrasts for 2.0 and 2.6 ppm were also ascertainable from the same spectra. CONCLUSION: ASEF can improve the CEST signal specificity of slow exchange labile protons such as amide and guanidyl, with small loss to sensitivity. It has strong potential in the CEST imaging of various diseases.


Assuntos
Roedores , Acidente Vascular Cerebral , Animais , Ratos , Roedores/metabolismo , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Prótons , Amidas/química , Niacinamida
8.
Magn Reson Med ; 89(2): 738-745, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36161668

RESUMO

PURPOSE: To develop a novel 3D abdominal CEST MRI technique at 3 T using MR multitasking, which enables entire-liver coverage with free-breathing acquisition. METHODS: k-Space data were continuously acquired with repetitive steady-state CEST (ss-CEST) modules. The stack-of-stars acquisition pattern was used for k-space sampling. MR multitasking was used to reconstruct motion-resolved 3D CEST images of 53 frequency offsets with entire-liver coverage and 2.0 × 2.0 × 6.0 mm3 spatial resolution. The total scan time was 9 min. The sensitivity of amide proton transfer (APT)-CEST (magnetization transfer asymmetry [MTRasym ] at 3.5 ppm) and glycogen CEST (glycoCEST) (mean MTRasym around 1.0 ppm) signals generated with the proposed method were tested with fasting experiments. RESULTS: Both APT-CEST and glycoCEST signals showed high sensitivity between post-fasting and post-meal acquisitions. APT-CEST and glycoCEST MTRasym signals from post-mean scans were significantly increased (APT-CEST: -0.019 ± 0.017 in post-fasting scans, 0.014 ± 0.021 in post-meal scans, p < 0.01; glycoCEST: 0.003 ± 0.009 in post-fasting scans, 0.027 ± 0.021 in post-meal scans, p < 0.01). CONCLUSION: The proposed 3D abdominal steady-state CEST method using MR multitasking can generate CEST images of the entire liver during free breathing.


Assuntos
Imageamento por Ressonância Magnética , Prótons , Humanos , Imageamento por Ressonância Magnética/métodos , Fígado/diagnóstico por imagem , Imageamento Tridimensional , Amidas
9.
Bioorg Chem ; 130: 106249, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356369

RESUMO

A series of 25 amides (15 new) derived from (3aR)-(+)-sclareolide were prepared and subjected to Ellman's assay to determine their efficacies as inhibitors for AChE or BuChE. Five amides (9, 13, 14, 15 and 17) caused inhibition of one of the enzymes greater than 60%; thereby those that inhibited BuChE were more active than positive control galantamine, and they showed better Ki values (1.07 to 8.49). In general, it was found that molecules holding a meta-substituted phenyl group showed a higher percentage of enzymatic inhibition. Molecular modelling calculations indicated the putative interactions of compounds with the amino acids residues of both enzymes AChE and BuChE. The cytotoxicity of compounds 9, 13, 14, 15 and 17 was evaluated against a non-malignant murine embryonic fibroblast cell line (NIH 3T3). Of special note is compound 15, as it presented the second-best Ki value for BuChE (1.71), was not cytotoxic (EC50 > 30 µM). Compound 15 also does not violate Lipinski rules, and showed permeability in the blood brain barrier, indicating that it can be considered a lead for the development of new drugs to treat Alzheimer's disease.


Assuntos
Acetilcolinesterase , Inibidores da Colinesterase , Camundongos , Animais , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Acetilcolinesterase/metabolismo , Amidas/farmacologia , Simulação de Acoplamento Molecular
10.
Bioorg Med Chem Lett ; 79: 129082, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36414174

RESUMO

Spinocerebellar ataxia type 31 is an autosomal dominant neurodegenerative disease caused by aberrant insertion of d(TGGAA)n into the intron shared by brain expressed, associated with Nedd4 and thymidine kinase 2 genes in chromosome 16. We reported that a naphthyridine dimer derivative with amidated linker structure (ND-amide) bound to GGA/GGA motifs in hairpin structures of d(TGGAA)n. The binding of naphthyridine dimer derivatives to the GGA/GGA motif was sensitive to the linker structures. The amidation of the linker in naphthyridine dimer improved the binding property to the GGA/GGA motif as compared with non-amidated naphthyridine dimer.


Assuntos
Ataxias Espinocerebelares , Humanos , Repetições de Microssatélites , Amidas , Polímeros , Naftiridinas
11.
Bioorg Med Chem Lett ; 79: 129080, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36414175

RESUMO

Smallpox was eradicated >40 years ago but it is not a reason to forget forever about orthopoxviruses pathogenic to humans. Though in 1980 the decision of WHO to cease vaccination against smallpox had seemed logical, it led to the decrease of cross immunity against other infections caused by orthopoxviruses. As a result, in 2022 the multi-country monkeypox outbreak becomes a topic of great concern. In spite of existing FDA-approved drugs for the treatment of such diseases, the search for new small-molecule orthopoxvirus inhibitors continues. In the course of this search a series of novel 2-aryl-1-hydroxyimidazole derivatives containing ester or carboxamide moieties in position 5 of heterocycle has been synthesized and tested for activity against Vaccinia virus in Vero cell culture. Some of the compounds under consideration revealed a selectivity index higher than that of the reference drug Cidofovir. The highest selectivity index SI = 919 was exhibited by ethyl 1-hydroxy-4-methyl-2-[4-(trifluoromethyl)phenyl]-1H-imidazole-5-carboxylate 1f. The most active compound also demonstrated inhibitory activity against the cowpox virus (SI = 20) and the ectromelia virus (SI = 46).


Assuntos
Orthopoxvirus , Varíola , Humanos , Ésteres , Ácidos Carboxílicos , Amidas , Antivirais/farmacologia , Imidazóis/farmacologia
12.
J Colloid Interface Sci ; 630(Pt A): 242-256, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242884

RESUMO

Photoluminescent polymer nanoparticles based on organic compounds are a new category of advanced materials with potential applications in various fields such as chemosensors, optical devices, drug-delivery systems, anticounterfeiting inks and bioimaging. Herein, amide functionalized copolymer nanoparticles with a particle size in the range of 42-139 nm were synthesized by emulsion copolymerization of methylmathacrylate (MMA) and methacrylamide (MAAm) with different concentrations in the range of 0-20 wt%. Afterward, the photoluminescent copolymer nanoparticles (PLCNPs) were prepared by physical modification of amide functionalized copolymer nanoparticles with 5 wt% of oxazolidine derivative (OXOH). Investigation of optical properties include of photoluminescence and UV-vis spectra displayed significant dependency of emission and absorbance bands to the local polarity or the concentration of the amide groups on the surface of the nanoparticles. Study of Commission Internationale de l'Eclairage (CIE) colorimetric diagrams for PLCNPs samples confirmed the results of photoluminescence and UV-vis spectra, which a logical shift in color of the photoluminescence emission was observed by an increase in the concentration of the amide groups. The PLCNPs samples have remarkable stability (in physical and optical properties) when applied on polar substrates such as polymer sheet and cellulose paper. Therefore, the PLCNPs samples were used for development of eco-friendly water based anticounterfeiting inks, photoluminescence organic light emitting diodes (OLEDs), and also the photodetection of scratches in a fast and facile manner. The printed security tags and hand-written phrases on cellulosic papers have orange fluorescent emission with maximum intensity because nanoscale size of particles, which reduced the light scattering and increased the accessible concentration of OXOH for light absorption. A coating of poly(vinyl alcohol) (PVA)/PLCNPs solution onto a blue LED (365 nm) was led to a change in the color of emission from blue to purple, because of the excitation of OXOH molecules at 365 nm with the subsequent emission of purple light. The photodetection of created scratch on polycarbonate sheet was carried out by spray of PLCNPs solution on sheet and then illumination with UV irradiation (365 nm). Developed water based PLCNPs samples have interesting optical properties, high stability on different surfaces and nanoscale particle size which are applicable in multiple applications such as eco-friendly photoluminescent inks for anticounterfeiting technologies, photoluminescence OLEDs, and also optical detector for monitoring of scratches on different substrates.


Assuntos
Nanopartículas , Polímeros , Polímeros/química , Nanopartículas/química , Água , Amidas
13.
J Hazard Mater ; 441: 129952, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36116312

RESUMO

The insecticide flonicamid (FLO) and its main degradation intermediate 4-trifluoromethylnicotinamide (TFNA-AM) are hazardous to the environment and animals. Microbial transformation of FLO has been well studied, but no study has yet reported on TFNA-AM degradation by a microorganism. Here, Pseudomonas stutzeri CGMCC 22915 effectively degraded TFNA-AM to 5-trifluoromethylnicotinic acid (TFNA). P. stutzeri CGMCC 22915 degraded 60.0% of TFNA-AM (1154.44 µmol/L) within 6 h with a half-life of just 4.5 h. Moreover, P. stutzeri CGMCC 22915 significantly promoted TFNA-AM decomposition in surface water. The reaction was catalyzed by an amidase, PsAmiA. PsAmiA is encoded in a novel nitrile-converting enzyme gene cluster. The enzyme shared only 20-44% identities with previously characterized signature amidases. PsAmiA was successfully expressed in Escherichia coli and its enzymatic properties were investigated using TFNA-AM as the substrate. PsAmiA was more active toward amides without hydrophilic groups, and did not hydrolyze another amide metabolite of FLO, N-(4-trifluoromethylnicotinoyl)glycinamide (TFNG-AM), which is structurally very similar to TFNA-AM. Molecular docking of PsAmiA and TFNA-AM indicated that hydrophobic residues Leu148, Ala150, Ala195, Ile225, Trp341, Leu460, and Ile463 may affect its substrate spectrum. This study provides new insights of the environmental fate of FLO at the molecular level and the structure-function relationships of amidases.


Assuntos
Inseticidas , Amidas , Amidoidrolases/genética , Animais , Inseticidas/química , Simulação de Acoplamento Molecular , Niacinamida/análogos & derivados , Nitrilas , Água
14.
J Environ Sci (China) ; 124: 915-922, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182194

RESUMO

As a biosorbent, algae are frequently used for the biotreatment or bioremediation of water contaminated by heavy metal or radionuclides. However, it is unclear that whether or not the biomineralization of these metal or radionuclides can be induced by algae in the process of bioremediation and what the mechanism is. In this work, Ankistrodsemus sp. has been used to treat the uranium-contaminated water, and more than 98% of uranium in the solution can be removed by the alga, when the initial uranium concentration ranges from 10 to 80 mg/L. Especially, an unusual phenomenon of algae-induced uranium biomineralization has been found in the process of uranium bioremediation and its mineralization mechanism has been explored by multiple approaches. It is worth noticing that the biomineralization of uranium induced by Ankistrodsemus sp. is significantly affected by contact time and pH. Uranium is captured rapidly on the cell surface via complexation with the carboxylate radical, amino and amide groups of the microalgae cells, which provides nucleation sites for the precipitation of insoluble minerals. Uranium stimulates Ankistrodsemus sp. to metabolize potassium ions (K+), which may endow algae with the ability to biomineralize uranium into the rose-like compreignacite (K2[(UO2)6O4(OH)6]•8H2O). As the time increased, the amorphous gradually converted into compreignacite crystals and a large number of crystals would expand over both inside and outside the cells. To the best of our knowledge, this is the first investigated microalgae with a time-dependent uranium biomineralization ability and superior tolerance to uranium. This work validates that Ankistrodsemus sp. is a promising alga for the treatment of uranium-contaminated wastewater.


Assuntos
Clorófitas , Urânio , Amidas , Biomineralização , Minerais/química , Potássio , Radioisótopos , Urânio/química , Compostos de Urânio , Águas Residuárias , Água
15.
Methods Mol Biol ; 2576: 261-274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152194

RESUMO

N-acylethanolamine-hydrolyzing acid amidase (NAAA) is a lysosomal hydrolase degrading various N-acylethanolamines at acidic pH. NAAA prefers anti-inflammatory and analgesic palmitoylethanolamide to other N-acylethanolamines as a substrate, and its specific inhibitors are shown to exert anti-inflammatory and analgesic actions in animal models. Therefore, these inhibitors are expected as a new class of therapeutic agents. Here, we introduce an NAAA assay system, using [14C]palmitoylethanolamide and thin-layer chromatography. The preparation of NAAA enzyme from native and recombinant sources as well as the chemical synthesis of N-[1'-14C]palmitoyl-ethanolamine is also described.


Assuntos
Amidoidrolases , Etanolaminas , Amidas , Amidoidrolases/química , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Inibidores Enzimáticos/farmacologia , Ácidos Palmíticos
16.
Biochim Biophys Acta Mol Cell Res ; 1870(1): 119367, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36202317

RESUMO

Studies suggested that the pathogenesis of inflammatory breast cancer (IBC) is related to inflammatory manifestations accompanied by specific cellular and molecular mechanisms in the IBC tumor microenvironment (TME). IBC is characterized by significantly higher infiltration of tumor-associated macrophages (TAMs) that contribute to its metastatic process via secreting many cytokines such as TNF, IL-6, IL-8, and IL-10 that enhance invasion and angiogenesis. Thus, there is a need to first understand how IBC-TME modulates the polarization of TAMs to better understand the role of TAMs in IBC. Herein, we used gene expression signature and Synchrotron Fourier-Transform Infrared Microspectroscopy (SR-µFTIR) to study the molecular and biochemical changes, respectively of in vitro polarized TAMs stimulated by the secretome of IBC and non-IBC cells. The gene expression signature showed significant differences in the macrophage's polarization-related genes between stimulated TAMs. FTIR spectra showed absorption bands in the region of 1700-1500 cm-1 attributed to the amide I ν(C=O), & νAS (CN), δ (NH), and amide II ν(CN), δ (NH) proteins bands. Moreover, three peaks of different intensities and areas were detected in the lipid region of the νCH2 and νCH3 stretching modes positioned within the 3000-2800 cm-1 range. The PCA analysis for the second derivative spectra of the amide regions discriminates between stimulated IBC and non-IBC TAMs. This study showed that IBC and non-IBC TMEs differentially modulate the polarization of TAMs and SR-µFTIR can determine these biochemical changes which will help to better understand the potential role of TAMs in IBC.


Assuntos
Neoplasias Inflamatórias Mamárias , Macrófagos Associados a Tumor , Humanos , Síncrotrons , Secretoma , Neoplasias Inflamatórias Mamárias/genética , Neoplasias Inflamatórias Mamárias/metabolismo , Neoplasias Inflamatórias Mamárias/patologia , Amidas , Microambiente Tumoral
17.
Talanta ; 251: 123772, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35970123

RESUMO

To date, the development of highly selective and efficient glycoproteins/peptides enrichment is still a challenge for mass spectrometry-based proteomic analysis. In this work, we reported a novel strategy to prepare a magnetic amide-linked covalent organic framework functionalized by benzoboroxole (denoted as Fe3O4@COF-ABB), which was then used as an adsorbent for the enrichment of glycoproteins. The physical and adsorption properties of Fe3O4@COF-ABB were fully investigated. The Fe3O4@COF-ABB presents a regular core-shell spherical structure, quick magnetic response performance, regular porosity, and multiple binding sites of phenylboronic acid. Taking advantage of these benefits, the synthesized magnetic composites exhibited a superior adsorption capacity (565.8 mg g-1) and high selectivity towards glycoprotein immunoglobulin G (IgG) under physiological state (pH 7.4). Additionally, the adsorbent Fe3O4@COF-ABB could be easily regenerated and reused 5 times with no reduction of enrichment performance. More importantly, the practical applications of Fe3O4@COF-ABB were further demonstrated by the selective adsorption of IgG from human serum. The present work represents a rational design of versatile functionalization of magnetic COFs, which demonstrates an avenue for the selective enrichment and analysis of IgG from real biological sample matrices.


Assuntos
Estruturas Metalorgânicas , Amidas , Glicoproteínas , Humanos , Imunoglobulina G , Fenômenos Magnéticos , Estruturas Metalorgânicas/química , Proteômica
18.
Methods Mol Biol ; 2552: 199-217, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36346593

RESUMO

In silico prediction methods were developed to predict protein asparagine (Asn) deamidation. The method is based on understanding deamidation mechanism on structural level with machine learning. Our structure-based method is more accurate than the sequence-based method which is still widely used in protein engineering process. In addition, molecular dynamics simulation was applied to study the time occupancy of nucleophilic attack distance, which is hypothesized as the most important step toward the rate-limiting succinimide intermediate formation. A more accurate prediction method for distinguishing potentially liable amino acid residues would allow their elimination or reduction as early as possible in the drug discovery process. It is possible that such quantitative protein structure-property relationship tools can also be applied to other protein hotspot predictions.


Assuntos
Asparagina , Proteínas , Asparagina/química , Amidas/química
19.
Food Chem ; 403: 134442, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36358078

RESUMO

More and more attention has been paid to undesirable chemical contaminants from food raw materials and ingredients. The study aimed to fabricate novel hydroxyl-functionalized magnetic porous organic polymer Fe3O4@SiO2-NH2@Ph-POP and explore its use as magnetic adsorbents for magnetic solid-phase extraction (MSPE) for extracting 31 amide herbicides from fruit wine samples prior to high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Several operational parameters were optimized and the as-prepared magnetic polymer displayed favorable extraction efficiency. The method also showed low limits of detection (0.015-1.412 µg·L-1) and limits of quantitation (0.049-4.707 µg·L-1). Recoveries for all of the herbicides in four different spiked level samples were between 65.06 % and 101.95 % with intra-day and inter-day relative standard deviations less than 9.89 % and 10.54 %, respectively. The proposed MSPE-HPLC-MS/MS method was successfully applied to simultaneously determine 31 amide herbicides in fruit wine.


Assuntos
Herbicidas , Vinho , Cromatografia Líquida de Alta Pressão/métodos , Herbicidas/análise , Espectrometria de Massas em Tandem , Vinho/análise , Polímeros/análise , Dióxido de Silício/química , Amidas/análise , Porosidade , Frutas/química , Extração em Fase Sólida/métodos , Fenômenos Magnéticos , Limite de Detecção
20.
Magn Reson Med ; 89(1): 177-191, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36063502

RESUMO

PURPOSE: To extract guanidinium (Guan) and amide CEST on the human brain at 3 T MRI with the high spectral resolution (HSR) CEST combined with the polynomial Lorentzian line-shape fitting (PLOF). METHODS: Continuous wave (cw) turbo spin-echo (TSE) CEST was implemented to obtain the optimum saturation parameters. Both Guan and amide CEST peaks were extracted and quantified using the PLOF method. The NMR spectra on the egg white phantoms were acquired to reveal the fitting range and the contributions to the amide and GuanCEST. Two types of CEST approaches, including cw gradient- and spin-echo (cwGRASE) and steady state EPI (ssEPI), were implemented to acquire multi-slice HSR-CEST. RESULTS: GuanCEST can be extracted with the PLOF method at 3 T, and the optimum B 1 = 0.6 µ T $$ {\mathrm{B}}_1=0.6\kern0.2em \upmu \mathrm{T} $$ was determined for GuanCEST in white matter (WM) and 1.0 µT in gray matter (GM). The optimum B1  = 0.8-1 µT was found for amideCEST. AmideCEST is lower in both WM and GM collected with ssEPI compared to those by cwGRASE (ssEPI = [1.27-1.63]%; cwGRASE = [2.19-2.25]%). The coefficients of variation (COV) of the amide and Guan CEST in both WM and GM for ssEPI (COV: 28.6-33.4%) are significantly higher than those of cwGRASE (COV: 8.6-18.8%). Completely different WM/GM contrasts for Guan and amide CEST were observed between ssEPI and cwGRASE. The amideCEST was found to have originated from the unstructured amide protons as suggested by the NMR spectrum of the unfolded proteins in egg white. CONCLUSION: Guan and amide CEST mapping can be achieved by the HSR-CEST at 3 T combing with the PLOF method.


Assuntos
Amidas , Encéfalo , Humanos , Guanidina/metabolismo , Amidas/química , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Imageamento por Ressonância Magnética/métodos , Substância Cinzenta
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