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1.
Molecules ; 29(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38398524

RESUMO

6-Iodo-substituted carboxy-quinolines were obtained using a one-pot, three-component method with trifluoroacetic acid as a catalyst under acidic conditions. Iodo-aniline, pyruvic acid and 22 phenyl-substituted aldehydes (we varied the type and number of radicals) or O-heterocycles, resulting in different electronic effects, were the starting components. This approach offers advantages such as rapid response times, cost-effective catalysts, high product yields and efficient purification procedures. A comprehensive investigation was conducted to examine the impact of aldehyde structure on the synthesis pathway. A library of compounds was obtained and characterized by FT-IR, MS, 1H NMR and 13C NMR spectroscopy and single-ray crystal diffractometry. Their antimicrobial activity against S. epidermidis, K. pneumonie and C. parapsilosis was tested in vitro. The effect of iodo-quinoline derivatives on microbial adhesion, the initial stage of microbial biofilm development, was also investigated. This study suggests that carboxy-quinoline derivatives bearing an iodine atom are interesting scaffolds for the development of novel antimicrobial agents.


Assuntos
Anti-Infecciosos , Iodo , Quinolinas , Espectroscopia de Infravermelho com Transformada de Fourier , Anti-Infecciosos/química , Quinolinas/química
2.
J Med Chem ; 67(4): 3018-3038, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38301036

RESUMO

New dihydro-pyrrol-2-one compounds, featuring dual sulfonamide groups, were synthesized through a one-pot, three-component approach utilizing trifluoroacetic acid as a catalyst. Computational analysis using density functional theory (DFT) and condensed Fukui function explored the structure-reactivity relationship. Evaluation against human carbonic anhydrase isoforms (hCA I, II, IX, XII) revealed potent inhibition. The widely expressed cytosolic hCA I was inhibited across a range of concentrations (KI 3.9-870.9 nM). hCA II, also cytosolic, exhibited good inhibition as well. Notably, all compounds effectively inhibited tumor-associated hCA IX (KI 1.9-211.2 nM) and hCA XII (low nanomolar). Biological assessments on MCF7 cancer cells highlighted the compounds' ability, in conjunction with doxorubicin, to significantly impact tumor cell viability. These findings underscore the potential therapeutic relevance of the synthesized compounds in cancer treatment.


Assuntos
Anidrases Carbônicas , Neoplasias , Humanos , Inibidores da Anidrase Carbônica/farmacologia , Anidrase Carbônica IX , Relação Estrutura-Atividade , Anidrases Carbônicas/metabolismo , Isoformas de Proteínas , Estrutura Molecular , Antígenos de Neoplasias
3.
Future Med Chem ; 15(15): 1369-1391, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37577781

RESUMO

Aim: A series of new hybrid molecules with two iodine atoms on the sides were synthesized. Methods: A one-pot, two-component method with trifluoroacetic acid as an effective catalyst to obtain dihydro-pyrrol-2-one compounds was developed. Short reaction times, a cheap catalyst, high yields and clean work-up are benefits of this method. Results: The chemical structures of the newly synthesized compounds were verified through spectroscopic techniques. Their antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans was tested in vitro. Conclusion: NC- and OH- radicals confer broad-spectrum antimicrobial activity, including against Gram-positive and Gram-negative bacteria and yeasts. Compounds 3g >7 and >9 were most active on the two bacterial species, while 3l >9 and >3i were most active against the fungal strain.

4.
Int J Mol Sci ; 24(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36982524

RESUMO

The paper aims to investigate the antitumor activity of a series of phenothiazine derivatives in order to establish a structure-antitumor activity relationship. To this end, PEGylated and TEGylated phenothiazine have been functionalized with formyl units and further with sulfonamide units via dynamic imine bonds. Their antitumor activity was monitored in vitro against seven human tumors cell lines and a mouse one compared to a human normal cell line by MTS assay. In order to find the potential influence of different building blocks on antitumor activity, the antioxidant activity, the ability to inhibit farnesyltransferase and the capacity to bind amino acids relevant for tumor cell growth were investigated as well. It was established that different building blocks conferred different functionalities, inducing specific antitumor activity against the tumor cells.


Assuntos
Antineoplásicos , Antipsicóticos , Neoplasias , Humanos , Animais , Camundongos , Relação Estrutura-Atividade , Fenotiazinas/farmacologia , Fenotiazinas/química , Antipsicóticos/farmacologia , Farnesiltranstransferase , Proliferação de Células , Polietilenoglicóis/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral
5.
Int J Biol Macromol ; 230: 123162, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623620

RESUMO

Due to its inherent properties and wide availability, cellulose acetate is an extremely competitive candidate for the production of polymeric membranes. However, for best results in particular applications, membrane modification is required in order to minimize unwanted interactions and introduce novel characteristics to the pristine polymer. In this study, the surface of commercial cellulose acetate membranes was functionalized with 4'-aminobenzo-15-crown-5 ether, using a covalent bonding approach. The main goal was the improvement of the membranes biomineralization ability, thus making them prospective materials for bone regeneration applications. The proposed reaction mechanism was confirmed by XPS and NMR analysis while the presence of the functionalization agents in the membranes structure was showed by ATR FT-IR and Raman spectra. The effects of the functionalization process on the morphology, thermal and mechanical properties of the membranes were studied by SEM, TGA and tensile tests. The obtained results revealed that the cellulose acetate membranes were successfully functionalized with crown ether and provided a good understanding of the interactions that took place between the polymer and the functionalization agents. Moreover, promising results were obtained during the Taguchi biomineralization studies. SEM images, EDX mapping and XRD spectra indicating that the CA-AB15C5 membranes have a superior Ca2+ ions retention ability, this causing an accentuated calcium phosphate deposition on the modified polymeric fibers, compared to the neat CA membrane.


Assuntos
Éteres de Coroa , Osseointegração , Espectroscopia de Infravermelho com Transformada de Fourier , Polímeros/química , Membranas Artificiais
6.
Molecules ; 27(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36500656

RESUMO

The specific features of the siloxane bond unify the compounds based on it into a class with its own chemistry and unique combinations of chemical and physical properties. An illustration of their chemical peculiarity is the behavior of 1,3-bis(2-aminoethylaminomethyl)tetramethyldisiloxane (AEAMDS) in the reaction with carbonyl compounds and metal salts, by which we obtain the metal complexes of the corresponding Schiff bases formed in situ. Depending on the reaction conditions, the fragmentation of this compound takes place at the siloxane bond, but, in most cases, it is in the organic moieties in the ß position with respect to the silicon atom. The main compounds that were formed based on the moieties resulting from the splitting of this diamine were isolated and characterized from a structural point of view. Depending on the presence or not of the metal salt in the reaction mixture, these are metal complexes with organic ligands (either dangling or not dangling silanol tails), or organic compounds. Through theoretical calculations, electrons that appear in the structure of the siloxane bond in different contexts and that lead to such fragmentations have been assessed.


Assuntos
Complexos de Coordenação , Complexos de Coordenação/química , Siloxanas/química , Bases de Schiff/química , Ligantes , Elétrons
7.
Diagnostics (Basel) ; 12(7)2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35885579

RESUMO

Most patients presenting in an emergency unit with acute coronary syndromes (ACS) (which include non-ST-elevation myocardial infarction (NSTEMI), ST-elevation MI (STEMI), and unstable angina) usually meet at least two cardiovascular risk factors, such as dyslipidemia, arterial hypertension, diabetes mellitus type 2, obesity, history of or current smoking, etc. Most ACS patients suffer from a type of dyslipidemia, and in addition to this there are ACS patients rushed into the emergency units for which the feeding status is unknown. Thus, we set out to evaluate the effect of fasting on 16 blood metabolite concentrations and 114 lipoprotein parameters on one control group and a group of statin-treated ACS patients hospitalized in a cardiovascular emergency unit, using Nuclear Magnetic Resonance (NMR) spectroscopy. The results indicated trends (in terms of number of cases, but not necessarily in terms of the magnitude of the effect) for as many as four metabolites and 48 lipoproteins. The effect was defined as a trend for results showing over 70% of the cases from either one or both groups that experienced parameter changes in the same direction (i.e., either increased or decreased). In terms of magnitude, the effect is rather low, leading to the overall conclusion that in cardiovascular (CV) emergency units, the blood samples analyzed in any feeding status would provide close results and very valuable information regarding prognosis and for fast decisions on patient's proper management.

8.
Environ Pollut ; 308: 119664, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35738521

RESUMO

Exposure to per- and polyfluoroalkyl substances (PFASs) is associated with increased blood cholesterol. Although elevated cholesterol is a well-established risk factor for cardiovascular diseases (CVD), it is not clear whether PFASs affect this risk. Lipoprotein subclasses are emerging biomarkers for disease risk and lipoprotein profiling may provide an insight to physiological implications of PFAS exposure. We explored the association between serum PFAS concentrations and lipoprotein subclasses in a cross-sectional study. We determined the concentrations and lipid composition of the major subclasses of lipoproteins in plasma samples from 127 adult participants of the EuroMix human biomonitoring study by nuclear magnetic resonance (NMR). Serum concentrations of 17 PFASs showed a detection frequency between 30 and 100% and were included in further analyses. We examined the associations between PFAS concentrations and lipoprotein subclasses by linear mixed-effect regression models, adjusted for confounders. In the adjusted models, positive associations were found between several PFASs and cholesterol concentrations in large to medium sized HDL and medium sized LDL particles. We found a 4-12% increase in HDL cholesterol per interquartile range (IQR) increase for several PFASs. In women the associations with PFNA, PFUnDA, PFDoDA and PFOS were significant after adjustment for multiple comparisons. Similar magnitude of change was observed between longer chained PFASs and LDL cholesterol, and a few of these associations reached significance for cholesterol in large to medium LDL particle sizes in women. No significant associations with plasma triglycerides were observed. However, most PFASs tended to be associated with reduction in VLDL (very low-density lipoproteins) particle number and VLDL triglyceride. Findings from this exploratory study, suggest that background PFAS exposures influence particle size distributions and lipid composition of plasma lipoprotein subclasses, and that these effects may be more prominent in women. A two-points lipoprofiling for all subjects indicated both low intra-individual variability and good analytical reproducibility.


Assuntos
Fluorocarbonos , Adulto , Monitoramento Biológico , Colesterol , Estudos Transversais , Feminino , Humanos , Lipoproteínas , Reprodutibilidade dos Testes
9.
Diagnostics (Basel) ; 12(3)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35328113

RESUMO

Nuclear magnetic resonance (NMR) metabolomics is currently popular enough to attract both specialized and non-specialized NMR groups involving both analytical trained personnel and newcomers, including undergraduate students. Recent interlaboratory studies performed by established NMR metabolomics groups demonstrated high reproducibility of the state-of-the-art NMR equipment and SOPs. There is, however, no assessment of NMR reproducibility when mixing both analytical experts and newcomers. An interlaboratory assessment of NMR quantitation reproducibility was performed using two NMR instruments belonging to different laboratories and involving several operators with different backgrounds and metabolomics expertise for the purpose of assessing the limiting factors for data reproducibility in a multipurpose NMR environment. The variability induced by the operator, automatic pipettes, NMR tubes and NMR instruments was evaluated in order to assess the limiting factors for quantitation reproducibility. The results estimated the expected reproducibility data in a real-life multipurpose NMR laboratory to a maximum 4% variability, demonstrating that the current NMR equipment and SOPs may compensate some of the operator-induced variability.

10.
Int J Mol Sci ; 23(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35269899

RESUMO

Novel fluorescent strigolactone derivatives that contain the piperidine-substituted 1,8-naphthalimide ring system connected through an ether link to a bioactive 3-methyl-furan-2-one unit were synthesized and their spectroscopic properties investigated. The solvatochromic behavior of these piperidine-naphthalimides was monitored in solvents of different polarity using the electronic absorption and fluorescence spectra. These compounds exhibited a strong positive solvatochromism taking into account the change of solvent polarity, and the response mechanism was analyzed by fluorescence lifetime measurements. According to Catalan and [f(n), f(ε), ß, α] solvent scales, the dipolarity and polarizability are relevant to describe the solute-solvent interactions. The emission chemosensing activity was discussed in order to determine the water content in organic environments. The emission intensity of these compounds decreased rapidly in dioxane, increasing water level up to 10%. Measuring of quantum yield indicated that the highest values of quantum efficiency were obtained in nonpolar solvents, while in polar solvents these derivatives revealed the lowest quantum yield. The fluorescence decay can be described by a monoexponential model for low water levels, and for higher water contents a biexponential model was valid.


Assuntos
Naftalimidas , Água , Fluorescência , Naftalimidas/química , Piperidinas , Solventes/química , Espectrometria de Fluorescência , Água/química
11.
Molecules ; 26(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34641496

RESUMO

Mesitylene was used as a core in seven new tritopic nitrogen containing linkers. Three of the linkers, each containing three nitrile groups, were obtained through Suzuki, Sonogashira and Heck-type coupling reactions. Next, these were converted to tetrazol-5-yl moieties by the cycloaddition of sodium azide to the nitrile functionalities. The last linker, containing three 1,2,3-triazol-4-yl moieties, was synthesized by the Huisgen cycloaddition of phenyl azide to the corresponding alkyne. The latter was obtained via a Corey-Fuchs reaction sequence from the previously reported formyl derivative. As the proof of concept for their potential in MOF design, one of the nitriles was used to build an Ag-based network.

12.
Molecules ; 25(22)2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33202577

RESUMO

The paper reports on monitoring methylmalonic aciduria (MMA)-specific and non-specific metabolites via NMR urinomics. Five patients have been monitored over periods of time; things involved were diet, medication and occasional episodes of failing to comply with prescribed diets. An extended dataset of targeted metabolites is presented, and correlations with the type of MMA are underlined. A survey of previous NMR studies on MMA is also presented.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/urina , Espectroscopia de Ressonância Magnética , Metabolômica , Criança , Pré-Escolar , Creatinina/urina , Feminino , Glicina/urina , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Tempo
13.
Int J Biol Macromol ; 165(Pt B): 2528-2540, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33098901

RESUMO

A new sponge-type hydrogel was obtained by cross-linking hyaluronic acid (HA) and poly(methylvinylether-alt-maleic acid) P(MVE-alt-MA) through a solvent-free thermal method. The sponge-type hydrogel was characterized and checked as a support for cell growth. The influence of concentration and weight ratio of polymers on the morphology and hydrogel stability was investigated. The total polymers concentration of 3% (w/w) and the weight ratio of 1:1 were optimal for the synthesis of a stable hydrogel (HA3P50) and to promote cell proliferation. The swelling measurements revealed a high-water absorption capacity of the hydrogel in basic medium. Diphenhydramine (DPH), lidocaine (Lid) and propranolol (Prop) were loaded within the hydrogel as a model drugs to investigate the ability of drug transport and release. In vitro studies revealed that HA3P50 hydrogel promoted the adhesion and proliferation of human hepatocellular carcinoma cell line HepG2, providing a good support for 3D cell culture to obtain surrogate tumor scaffold suitable for preclinical anti-cancer drug screening.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ácido Hialurônico/química , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Hidrogéis/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Difenidramina/farmacologia , Células Hep G2 , Humanos , Ácido Hialurônico/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogéis/química , Lidocaína/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Maleatos/química , Maleatos/farmacologia , Propranolol/farmacologia
14.
Chem Biodivers ; 17(7): e2000175, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32333466

RESUMO

Two chitosan extracts were prepared by chemical and enzymatic treatment of Ganoderma lucidum mushroom, as an alternative source to crustacean shells. The molecular weight of the enzymatic extract was lower than that of the chemical one and of shrimp chitosan, as determined by viscosity measurements. Characteristic signals were identified in the 1 H-NMR spectra and high deacetylation degree indicated good physico-chemical properties for both mushroom chitosan extracts. The scavenging capacity of mushroom chitosan extracts was moderate against the synthetic radicals of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH), but higher values were observed for the enzymatic extract, compared to the chemical extract and shrimp chitosan. In vitro cytotoxicity was evaluated in L929 mouse fibroblast cell lines and the results of MTT assay showed good cytocompatibility in the tested range of concentrations. The growth of Gram-positive bacteria was inhibited more than Gram-negative bacteria in the presence of mushroom chitosan extracts, in particular by the chemical one, indicating their efficiency as antimicrobial agents. All these results strengthen the evidence of mushroom polysaccharide preparations availability for biomedical applications.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Quitosana/farmacologia , Reishi/química , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quitosana/química , Quitosana/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Picratos/antagonistas & inibidores , Relação Estrutura-Atividade , Ácidos Sulfônicos/antagonistas & inibidores
15.
RSC Adv ; 10(63): 38304-38315, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35517536

RESUMO

A novel DPyDB-C[double bond, length as m-dash]N-18C6 compound was synthesised by linking a pyrene moiety to each phenyl group of dibenzo-18-crown-6-ether, the crown ether, through -HC[double bond, length as m-dash]N- bonds and characterized by FTIR, 1H-NMR, 13C-NMR, TGA, and DSC techniques. The quantitative 13C-NMR analysis revealed the presence of two position isomers. The electronic structure of the DPyDB-C[double bond, length as m-dash]N-18C6 molecule was characterized by UV-vis and fluorescence spectroscopies in four solvents with different polarities to observe particular behavior of isomers, as well as to demonstrate a possible non-bonding chemical association (such as ground- and excited-state associations, namely, to probe if there were forming dimers/excimers). The interpretation of the electronic structure was realized through QM calculations. The TD-CAM-B3LYP functional, at the 6-311+G(d,p) basis set, indicated the presence of predominant π → π* and mixed π → π* + n → π* transitions, in line with the UV-vis experimental data. Even though DPyDB-C[double bond, length as m-dash]N-18C6 computational studies revealed a π-extended conjugation effect with predominantly π → π* transitions, thorough fluorescence analysis was observed a weak emission, as an effect of PET and ACQ. In particular, the WAXD analysis of powder and thin films obtained from n-hexane, 1,2-dichloroethane, and ethanol indicated an amorphous organization, whereas from toluene a smectic ordering was obtained. These results were correlated with MD simulation, and it was observed that the molecular geometry of DPyDB-C[double bond, length as m-dash]N-18C6 molecule played a defining role in the pyrene stacking arrangement.

16.
Int J Biol Macromol ; 143: 200-212, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31816371

RESUMO

The chitosan hydrochloride (Cs·HCl) was obtained as a polymer soluble in physiological solutions to be used as potential support for safely cell culture or cell encapsulation. Viability tests showed that concentrations between 0.16 and 5 mg/mL of Cs·HCl were not toxic for the HEK293 cells. In parallel, aldehyde-functionalized pullulan (Pul-CHO) was synthesized as the macromolecular cross-linker. Cs·HCl was dissolved in 0.9% NaCl and injected (INJECTOMAT SEP 21S PLUS) through a needle to obtain small droplets in a sodium tripolyphosphate solution in the absence and presence of 0.1% (w/v) Pul-CHO. Simple and dual cross-linked millicapsules were obtained with pore size ranging from 50 µm to 5 µm, respectively. FITC-Dextran with molecular weights of 4000 and 70,000 g/mol was encapsulated during microcapsule synthesis as macromolecular models to check the permeability of Cs millicapsules. The results show that FITC-Dextran 4000 and 70,000 diffuses quickly from simple cross-linked millicapsules while dual cross-linked millicapsules release slowly both FITC-dextrans. Microscopy experiments show that HEK 293 cells adhere to the surface of millicapsules. Taken together the data reveal that Cs millicapsules allow the cell growth on their surface, and thus, they offer new perspectives for cell encapsulation strategy.


Assuntos
Técnicas de Cultura de Células , Encapsulamento de Células , Quitosana/química , Reagentes de Ligações Cruzadas/química , Quitosana/síntese química , Quitosana/farmacologia , Reagentes de Ligações Cruzadas/síntese química , Reagentes de Ligações Cruzadas/farmacologia , Dextranos/química , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Glucanos/síntese química , Glucanos/química , Células HEK293 , Humanos
17.
Molecules ; 24(16)2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31412649

RESUMO

Zinnia elegans (syn. Zinnia violacea) is a common ornamental plant of the Asteraceae family, widely cultivated for the impressive range of flower colors and persistent bloom. Given its uncomplicated cultivation and high adaptability to harsh landscape conditions, we investigated the potential use of Z. elegans as a source of valuable secondary metabolites. Preliminary classification of compounds found in a methanolic extract obtained from inflorescences of Z. elegans cv. Caroussel was accomplished using HR LC-MS techniques. The extract was then subjected to solid-phase extraction and separation using Sephadex LH-20 column chromatography, which resulted in several fractions further investigated for their antioxidant properties through lipoxygenase inhibition and metal chelating activity assays. Moreover, following additional purification procedures, structures of some active ingredients were established by NMR spectroscopy. The investigated fractions contained polyphenolic compounds such as chlorogenic acids and apigenin, kaempferol, and quercetin glycosides. Antioxidant assays showed that certain fractions exhibit moderate 15-LOX inhibition (Fr 2, IC50 = 18.98 µg/mL) and metal chelation (e.g., Fr 1-2, EC50 = 0.714-1.037 mg/mL) activities as compared to positive controls (20.25 µg/mL for kaempferol and 0.068 mg/mL for EDTA, respectively). For Fr 2, the 15-LOX inhibition activity seems to be related to the abundance of kaempferol glycosides. The NMR analyses revealed the presence of a kaempferol 3-O-glycoside, and a guanidine alkaloid previously not described in this species.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Asteraceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/isolamento & purificação , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Fitoquímicos/química , Extratos Vegetais/isolamento & purificação
18.
Pharmaceutics ; 11(6)2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31234525

RESUMO

In this study, we proposed formulations of diminazene aceturate (DA) designed to improve its bioavailability and to maximize the therapeutic index in animals by overcoming the rapid degradation under the acidic pH of the stomach. An important consequence is the fact that its amount in the bloodstream is close to the administered dose. This was made possible by incorporating DA into the ß-cyclodextrin's (ßCD) cavity in a molar ratio of 1:1. The structure of the resulted inclusion complex was established by Raman, DSC, and Wide-Angle X ray Diffraction (WAXD) in solid state and by 1H-NMR and H-H ROESY in aqueous solutions. The stoichiometry of the DA:ßCD inclusion complex was obtained by using the continuous variation method (Job's plot), considering the chemical shifts variations of protons from both DA and ßCD compounds in 1H-NMR spectra. The biological activity was estimated in vitro by antioxidant activity and in vivo by comparing the bioavailability of parent DA and its inclusion complexes after a single dose administration in Wistar rats by using the HPLC method on their blood plasma. In vitro tests showed an improved antioxidant activity. In vivo tests have shown that the DA concentration is always much higher in blood plasma of rats when DA:ßCD inclusion complex of 1:1 molar ratio was administered (i.e., at 60 min, DA is around 11 and 3 times higher when DA:ßCD inclusion complex of 1:1 molar ratio was administered than the parent DA one and DA:ßCD lyophilized mixture of 1:2 molar ratio, respectively).

19.
Medicina (Kaunas) ; 55(4)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987402

RESUMO

Classic galactosemia is an autosomal recessive disorder caused by the deficiency of the enzyme galactose-1-phosphate uridyltransferase (GALT) involved in galactose metabolism. Bacterial infections are a known cause of early morbidity and mortality in children with classic galactosemia. The most common agent is Escherichia coli, but in rare situations, other bacteria are incriminated. We report a case of a three-week-old female patient with galactosemia, who presented with Group B Streptococcus (GBS) meningitis/sepsis. She received treatment with antibiotics, supportive therapy, and erythrocyte transfusion, but after a short period of improvement, she presented acute liver failure with suspicion of an inborn error of metabolism. Rapid nuclear magnetic resonance (NMR) spectroscopy from urine showed highly elevated values of galactose and galactitol. Under intensive treatment for acute liver failure and with a lactose-free diet, her clinical features and laboratory parameters improved considerably. Genetic testing confirmed compound heterozygous status for GALT mutations: c.563 A>G [p.Q188R] and c. 910 C>T, the last mutation being a novel mutation in GALT gene. In countries without an extensive newborn screening program, a high index of suspicion is necessary for early diagnosis and treatment of galactosemia.


Assuntos
Galactosemias/complicações , Galactosemias/genética , Falência Hepática Aguda/complicações , Meningites Bacterianas/complicações , Infecções Estreptocócicas/complicações , UTP-Hexose-1-Fosfato Uridililtransferase/genética , Pré-Escolar , Países Desenvolvidos , Feminino , Seguimentos , Galactitol/urina , Galactose/urina , Galactosemias/dietoterapia , Galactosemias/urina , Humanos , Recém-Nascido , Teste de Tolerância a Lactose , Falência Hepática Aguda/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Meningites Bacterianas/tratamento farmacológico , Mutação , Triagem Neonatal , Romênia , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus
20.
Faraday Discuss ; 209(0): 67-82, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-29989626

RESUMO

Water uptake in vesicles and the subsequent exchange between water protons and amide -NH protons in amino acids can be followed by a new, highly sensitive, type of magnetic resonance spectroscopy: dynamic nuclear polarisation (DNP)-enhanced NMR in the liquid state. Water hydrogen atoms are detected prior to and after their transfer to molecular sites in peptides and proteins featuring highly-accessible proton-exchangeable groups, as is the case for the -NH groups of intrinsically disordered proteins. The detected rates for amide proton-water proton exchange can be modulated by membrane-crossing rates, when a membrane channel is interposed. We hyperpolarised water proton spins via dynamic nuclear polarisation followed by sample dissolution (d-DNP) and transferred the created polarisation to -NH groups with high solvent accessibility in an intrinsically disordered protein domain. This domain is the membrane anchor of c-Src kinase, whose activity controls cell proliferation. The hindrance of effective water proton transfer rate constants observed in free solvent when a membrane-crossing step is involved is discussed. This study aims to assess the feasibility of recently-introduced hyperpolarised (DNP-enhanced) NMR to assess water membrane crossing dynamics.


Assuntos
Canais Iônicos/química , Peptídeos/química , Proteínas/química , Prótons , Água/química , Espectroscopia de Ressonância Magnética
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