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1.
Sensors (Basel) ; 23(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36772728

RESUMO

Three coumarin-based boron complexes (L1, L2 and L3) were designed and successfully incorporated into polymeric matrixes for evaluation as temperature probes. The photophysical properties of the complexes were carried out in different solvents and in the solid state. In solution, compound L1 exhibited the highest fluorescence quantum yield, 33%, with a positive solvatochromism also being observed on the absorption and emission when the polarity of the solvent increased. Additionally in the presence of anions, L1 showed a colour change from yellow to pink, followed by a quenching in the emission intensity, which is due to deprotonation with the formation of a quinone base. Absorption and fluorescence spectra of L1 were calculated at different temperatures by the DFT/B3LYP method. The decrease in fluorescence of compound L1 with an increase in temperature seems to be due to the presence of pronounced torsional vibrations of the donor and acceptor fragments relative to the single bond with C(carbonyl)-C (styrene fragment). L1, L2 and L3, through their incorporation into the polymeric matrixes, became highly emissive by aggregation. These dye@doped polymers were evaluated as temperature sensors, showing an excellent fluorescent response and reversibility after 15 cycles of heating and cooling.

2.
Heliyon ; 8(9): e10541, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36132170

RESUMO

In this study, we compare several peak profile analysis methods for the investigation of the CoCrFeMnNi high-entropy alloy (HEA) after the plastic deformation. We show that conventional Williamson - Hall (cWH) approach poorly correlates with measured peak broadening and some corrections must be introduced to improve the analysis. The correction for elastic modulus for different crystallographic directions or application of modified Williamson Hall (mWH) and modified Warren - Averbach (mWA) methods significantly improve the correlation between the model and experimental data. Peak profile analysis shows that the dislocation density of the CoCrFeMnNi alloy subjected to axial compression increases with increase in strain and reaches plateau at a strain of 47.5%. At the same time, the crystallite size decreases, and dislocation structure becomes more disordered.

3.
Pharmaceuticals (Basel) ; 15(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35215268

RESUMO

The emergence of drug resistance in pathogens leads to a loss of effectiveness of antimicrobials and complicates the treatment of bacterial infections. Quinoxaline 1,4-dioxides represent a prospective scaffold for search of new compounds with improved chemotherapeutic characteristics. Novel 2-acyl-3-trifluoromethylquinoxaline 1,4-dioxides with alteration of substituents at position 2 and 6 were synthesized via nucleophilic substitution with piperazine moiety and evaluated against a broad panel of bacteria and fungi by measuring their minimal inhibitory concentrations. Their mode of action was assessed by whole-genomic sequencing of spontaneous drug-resistant Mycobacterium smegmatis mutants, followed by comparative genomic analysis, and on an original pDualrep2 system. Most of the 2-acyl-3-trifluoromethylquinoxaline 1,4-dioxides showed high antibacterial properties against Gram-positive strains, including mycobacteria, and the introduction of a halogen atom in the position 6 of the quinoxaline ring further increased their activity, with 13c being the most active compound. The mode of action studies confirmed the DNA-damaging nature of the obtained quinoxaline 1,4-dioxides, while drug-resistance may be provided by mutations in redox homeostasis genes, encoding enzymes potentially involved in the activation of the compounds. This study extends views about the antimicrobial and antifungal activities of the quinoxaline 1,4-dioxides and can potentially lead to the discovery of new antibacterial drugs.

4.
Eur J Med Chem ; 228: 113997, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34902732

RESUMO

Carbonic anhydrase IX is a promising target for the search for new antitumor compounds with improved properties. Using the molecular hybridization approach, on the basis of structures of a selective carbonic anhydrase IX inhibitor 3 and an activator of apoptosis 2 (1), a series of 1-substituted isatin-5-sulfonamides 5a-5u were designed and synthesized. The study of the inhibitory activity of isatin-5-sulfonamides showed the ability to inhibit I, II, IX, XII isoforms at nano- and micromolar concentrations. Docking of compounds 5e and 5k into the active site of II and IX carbonic anhydrase isoforms showed the coordination of sulfonamidate anions with zinc cations, as well as a number of additional hydrophobic interactions. The trifluoromethylthio derivative 5r suppressed the growth of tumor cells at low micromolar concentrations, maintaining activity on resistant lines and under hypoxic conditions. Immunoblotting of MCF7 cells treated with the 5r revealed its antiestrogenic activity and ability to activate apoptosis in tumor cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Isatina/farmacologia , Sulfonamidas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Isatina/síntese química , Isatina/química , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química
5.
Microorganisms ; 8(12)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353204

RESUMO

Gut microbiota and the host exist in a mutualistic relationship, with the functional composition of the microbiota strongly influencing the health and well-being of the host. In addition to the standard differential expression analysis of host genes to assess the complex cross-talk between environment (diet), microbiome, and host intestinal physiology, data-driven integrative approaches are needed to identify potential biomarkers of both host genes and microbial communities that characterize these interactions. Our findings demonstrate that the complementary application of univariate differential gene expression analysis and multivariate approaches such as sparse Canonical Correlation Analysis (sCCA) and sparse Principal Components Analysis (sPCA) can be used to integrate data from both the healthy infant gut microbial community and host transcriptome (exfoliome) using stool derived exfoliated cells shed from the gut. These approaches reveal host genes and microbial functional categories related to the feeding phenotype of the infants. Our findings also confirm that combinatorial noninvasive -omic approaches provide an integrative genomics-based perspective of neonatal host-gut microbiome interactions.

6.
Am J Vet Res ; 81(7): 581-593, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32584185

RESUMO

OBJECTIVE: To compare analgesic efficacy and fetal effects between transdermal administration of fentanyl and IM administration of buprenorphine in pregnant sheep. ANIMALS: 12 healthy pregnant ewes. PROCEDURES: Before study initiation, each ewe was confirmed pregnant with a single fetus between 113 and 117 days of gestation. Ewes were randomly assigned to receive buprenorphine (0.01 mg/kg, IM, q 8 h for 48 hours beginning 1 hour before anesthesia induction; n = 6) or fentanyl (a combination of transdermal fentanyl patches sufficient to deliver a dose of 2 µg of fentanyl/kg/h applied between the dorsal borders of the scapulae 24 hours before anesthesia induction; 6). Ewes were anesthetized and underwent a surgical procedure to instrument the fetus with an arterial catheter and place a catheter in utero for collection of amniotic fluid samples. Physiologic variables and behavioral changes indicative of pain were assessed, and amniotic fluid and blood samples from ewes and fetuses were collected for determination of drug concentrations at predetermined times. RESULTS: Both protocols provided acceptable postoperative analgesia with no adverse effects observed in the ewes or fetuses. Compared with the buprenorphine protocol, the fentanyl protocol induced more profound analgesia, decreased the requirement for isoflurane during surgery, and was associated with a shorter anesthesia recovery time. Fetal indices did not differ significantly between the 2 analgesic protocols. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that both protocols provided acceptable analgesia. However, the fentanyl protocol was superior in regard to the extent of analgesia induced, inhalant-sparing effects, and anesthesia recovery time.


Assuntos
Buprenorfina , Fentanila , Dor Pós-Operatória , Administração Cutânea , Analgésicos , Analgésicos Opioides , Animais , Feminino , Feto , Dor Pós-Operatória/veterinária , Gravidez , Ovinos
7.
Photochem Photobiol ; 96(4): 798-804, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31900923

RESUMO

Photophysical characteristics of new 3-(1-acyl-5-aryl-3-pyrazolinyl)coumarins have been measured. These coumarin derivatives are found to be effective fluorophores and show high values of quantum yields of fluorescence both in nonpolar and in polar solvents. The 3-(1-acyl-5-aryl-3-pyrazolinyl)coumarins turned to be photosensitive compounds and undergo photolysis under irradiation in the range of 310-465 nm. Photolysis is suggested to include retro-cyclization and retro-condensation steps. The process is accompanied by a sharp drop of fluorescence that can be of interest for the creation of new media in optical recording of information.

8.
Photochem Photobiol ; 95(4): 924-930, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30613996

RESUMO

Photooxidation of aryl(hetaryl)pyrazolines in the presence of benzoquinone has been studied in organic solvents. This reaction occurs at high rate to provide the corresponding pyrazole in a good yield. The effects of the solvent, pyrazoline structure and oxygen provide definite information on the reaction pathway. It appears that radical species are intermediates in the photooxidation of aryl(hetaryl)pyrazolines in the presence of benzoquinone. A comparison of the new results with the photooxidation of aryl(hetaryl)pyrazolines in the presence of perchloroalkanes is also discussed.

9.
Photochem Photobiol ; 94(4): 659-666, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29526037

RESUMO

New (1,5-diaryl-3-pyrazolinyl)coumarins have been synthesized. The compounds do not undergo keto-enol tautomeric transformations with changes in the solvent. (1,5-Diaryl-3-pyrazolinyl)coumarins provide dehydrogenation reaction under irradiation in the presence of perchloroalkanes and manifest themselves as effective photogenerators of acidity. Several aspects of photodehydrogenation mechanism have been studied. Oxygen is shown not be involved in the reaction. Polar solvents increase rate of the reaction. The measured rate constants of the photodehydrogenation reactions vary in a significant range according to the structure of pyrazoline. The data correlate with ionization potentials of pyrazolines available from DFT quantum chemical calculations. These results are discussed in terms of proposed scheme of mechanism of pyrazolines photodehydrogenation assuming formation of ion-radical and ion intermediates.

10.
Sci Rep ; 4: 5453, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24965658

RESUMO

The state and development of the intestinal epithelium is vital for infant health, and increased understanding in this area has been limited by an inability to directly assess epithelial cell biology in the healthy newborn intestine. To that end, we have developed a novel, noninvasive, molecular approach that utilizes next generation RNA sequencing on stool samples containing intact epithelial cells for the purpose of quantifying intestinal gene expression. We then applied this technique to compare host gene expression in healthy term and extremely preterm infants. Bioinformatic analyses demonstrate repeatable detection of human mRNA expression, and network analysis shows immune cell function and inflammation pathways to be up-regulated in preterm infants. This study provides incontrovertible evidence that whole-genome sequencing of stool-derived RNA can be used to examine the neonatal host epithelial transcriptome in infants, which opens up opportunities for sequential monitoring of gut gene expression in response to dietary or therapeutic interventions.


Assuntos
Fezes/citologia , Perfilação da Expressão Gênica/métodos , Mucosa Intestinal/fisiologia , Proteoma/metabolismo , RNA/genética , Análise de Sequência de RNA/métodos , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Proteoma/genética
11.
Int J Nanomedicine ; 8 Suppl 1: 45-56, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098078

RESUMO

BACKGROUND: There is a need to take a broader look at nanotoxicological studies. Eventually, the field will demand that some generalizations be made. To begin to address this issue, we posed a question: are metal colloids on the nanometer-size scale a homogeneous group? In general, most people can agree that the physicochemical properties of nanomaterials can be linked and related to their induced toxicological responses. METHODS: The focus of this study was to determine how a set of selected physicochemical properties of five specific metal-based colloidal materials on the nanometer-size scale - silver, copper, nickel, iron, and zinc - could be used as nanodescriptors that facilitate the grouping of these metal-based colloids. RESULTS: The example of the framework pipeline processing provided in this paper shows the utility of specific statistical and pattern recognition techniques in grouping nanoparticles based on experimental data about their physicochemical properties. Interestingly, the results of the analyses suggest that a seemingly homogeneous group of nanoparticles could be separated into sub-groups depending on interdependencies observed in their nanodescriptors. CONCLUSION: These particles represent an important category of nanomaterials that are currently mass produced. Each has been reputed to induce toxicological and/or cytotoxicological effects. Here, we propose an experimental methodology coupled with mathematical and statistical modeling that can serve as a prototype for a rigorous framework that aids in the ability to group nanomaterials together and to facilitate the subsequent analysis of trends in data based on quantitative modeling of nanoparticle-specific structure-activity relationships. The computational part of the proposed framework is rather general and can be applied to other groups of nanomaterials as well.


Assuntos
Coloides/química , Nanopartículas Metálicas/química , Metais Pesados/química , Análise Discriminante , Concentração de Íons de Hidrogênio , Análise de Componente Principal , Relação Estrutura-Atividade , Propriedades de Superfície
12.
Genome Biol ; 13(4): r32, 2012 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-22546241

RESUMO

BACKGROUND: Gut microbiota and the host exist in a mutualistic relationship, with the functional composition of the microbiota strongly affecting the health and well-being of the host. Thus, it is important to develop a synthetic approach to study the host transcriptome and the microbiome simultaneously. Early microbial colonization in infants is critically important for directing neonatal intestinal and immune development, and is especially attractive for studying the development of human-commensal interactions. Here we report the results from a simultaneous study of the gut microbiome and host epithelial transcriptome of three-month-old exclusively breast- and formula-fed infants. RESULTS: Variation in both host mRNA expression and the microbiome phylogenetic and functional profiles was observed between breast- and formula-fed infants. To examine the interdependent relationship between host epithelial cell gene expression and bacterial metagenomic-based profiles, the host transcriptome and functionally profiled microbiome data were subjected to novel multivariate statistical analyses. Gut microbiota metagenome virulence characteristics concurrently varied with immunity-related gene expression in epithelial cells between the formula-fed and the breast-fed infants. CONCLUSIONS: Our data provide insight into the integrated responses of the host transcriptome and microbiome to dietary substrates in the early neonatal period. We demonstrate that differences in diet can affect, via gut colonization, host expression of genes associated with the innate immune system. Furthermore, the methodology presented in this study can be adapted to assess other host-commensal and host-pathogen interactions using genomic and transcriptomic data, providing a synthetic genomics-based picture of host-commensal relationships.


Assuntos
Aleitamento Materno , Fórmulas Infantis/administração & dosagem , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Metagenoma/imunologia , Metagenômica/métodos , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/imunologia , Actinobacteria/isolamento & purificação , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/imunologia , Bacteroidetes/isolamento & purificação , Fezes/microbiologia , Perfilação da Expressão Gênica , Humanos , Lactente , Fórmulas Infantis/metabolismo , Mucosa Intestinal/citologia , Análise Multivariada , Filogenia , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/imunologia , Proteobactérias/isolamento & purificação , RNA Bacteriano/análise , RNA Bacteriano/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Análise de Sequência de RNA , Simbiose , Transcrição Gênica , Transcriptoma
13.
Birth Defects Res A Clin Mol Teratol ; 85(6): 546-55, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19229884

RESUMO

BACKGROUND: Neural tube defects (NTDs) are one of the most common human birth defects, with a prevalence of approximately 1 in 1000 live births in the United States. In animal studies, deletion of p53 leads to a significant increase in embryos that exhibit exencephaly. Whereas several studies have closely investigated the morphologic changes of p53-deficient embryos, no study has reported the molecular-level alteration in p53-deficient embryos. Here we attempt to identify genes and microRNAs (miRNAs) modified by deletion of p53 in day 8.5 mouse embryos. METHODS: Mouse embryos from p53 heterozygous crosses were collected, genotyped, and embryos of similar genotype (+/+; +/-; -/-) were pooled. RNA from the pooled samples was isolated to determine mRNA and miRNA expression levels using Whole Genome Bioarrays and Low Density Arrays, respectively. RESULTS: In p53 -/- embryos, 388 genes showed statistically significant alteration in gene expression of more than twofold compared to p53 +/+ embryos. Expression of p53 and well known p53 target genes, such as p21 and cyclin G1, were significantly down-regulated in p53 -/- embryos. In contrast, expression of other p53 target genes, such as Mdm2, Noxa, and Puma, were unchanged. We also identified six genes (Csk, Itga3, Jarid2, Prkaca, Rarg, and Sall4), known to cause NTDs when deleted, that are also down-regulated in p53 -/- embryos. Finally, five miRNAs (mir-1, mir-30e-3p, mir-142-3p, mir-301, and mir-331) also showed statistically significant alterations in expression levels in p53 -/- embryos compared to p53 +/+ embryos. Combined analysis of the experimental data using stepwise regression model and two publicly available algorithms identified putative target genes of these miRNAs. CONCLUSIONS: Our data have identified genes and miRNAs that may be involved in the mechanisms underlining NTDs and begin to define the developmental role of p53 in the etiology of NTDs.


Assuntos
Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/biossíntese , Defeitos do Tubo Neural/metabolismo , Proteína Supressora de Tumor p53 , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/genética , Defeitos do Tubo Neural/genética
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