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1.
Int J Biol Macromol ; 253(Pt 3): 126933, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37722631

RESUMO

Wound healing is a complex process; therefore, new dressings are frequently required to facilitate it. In this study, porous bacterial levan-based sponges containing cannabis oil (Lev@CBDs) were prepared and fully characterized. The sponges exhibited a suitable swelling ratio, proper water vapor transmission rate, sufficient thermal stability, desired mechanical properties, and good antioxidant and anti-inflammatory properties. The obtained Lev@CBD materials were evaluated in terms of their interaction with proteins, human serum albumin and fibrinogen, of which fibrinogen revealed the highest binding effect. Moreover, the obtained biomaterials exhibited antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa, as well as being non-hemolytic material as indicated by hemolysis tests. Furthermore, the sponges were non-toxic and compatible with L929 mouse fibroblasts and HDF cells. Most significantly, the levan sponge with the highest content of cannabis oil, in comparison to others, retained its non-hemolytic, anti-inflammatory, and antimicrobial properties after prolonged storage in a climate chamber at a constant temperature and relative humidity. The designed sponges have conclusively proven their beneficial physicochemical properties and, at the preliminary stage, biocompatibility as well, and therefore can be considered a promising material for wound dressings in future in vivo applications.


Assuntos
Quitosana , Camundongos , Animais , Humanos , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Bandagens , Fibrinogênio , Anti-Inflamatórios
2.
Molecules ; 28(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37446877

RESUMO

Ferrocene is useful in modern organometallic chemistry due to its versatile applications in material sciences, catalysis, medicinal chemistry, and diagnostic applications. The ferrocene moiety can potentially serve many purposes in therapeutics and diagnostics. In the course of this study, (6-bromo-1-oxohexyl)ferrocene was combined with dimercaptomaleonitrile sodium salt to yield a novel maleonitrile derivative. Subsequently, this compound was subjected to an autocyclotetramerization reaction using the Linstead conditions in order to obtain an octaferrocenyl-substituted magnesium(II) sulfanyl porphyrazine. Following that, both compounds-the maleonitrile derivative and the porphyrazine derivative-were subjected to physicochemical characterization using UV-Vis, ES-TOF, MALDI-TOF, and one-dimensional and two-dimensional NMR spectroscopy. Moreover, the sulfanyl porphyrazine was subjected to various photophysical studies, including optical absorption and emission measurements, as well as the evaluation of its photochemical properties. Values of singlet oxygen generation quantum yields were obtained in different organic solvents. The electrochemical properties of the synthesized compounds were studied using cyclic voltammetry. According to the electrochemical results, the presence of electron-withdrawing oxohexyl groups attached to ferrocene afforded significantly more positive oxidation potentials of the ferrocene-based redox process up to 0.34 V vs. Fc+/Fc.


Assuntos
Oxigênio Singlete , Metalocenos , Oxirredução , Oxigênio Singlete/química , Solventes
3.
Molecules ; 27(14)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35889282

RESUMO

A sulfanyl porphyrazine derivative with peripheral phthalimide moieties was metallated with cobalt(II) and iron(II) metal ions. The purity of the macrocycles was confirmed by HPLC, and subsequently, compounds were characterized using various analytical methods (ES-TOF, MALDI-TOF, UV-VIS, and NMR spectroscopy). To obtain hybrid electroactive electrode materials, novel porphyrazines were combined with multiwalled carbon nanotubes. The electrocatalytic effect derived from cobalt(II) and iron(II) cations was evaluated. As a result, a significant decrease in the overpotential was observed compared with that obtained with bare glassy carbon (GC) or glassy carbon electrode/carbon nanotubes (GC/MWCNTs), which allowed for sensitive determination of hydrogen peroxide in neutral conditions (pH 7.4). The prepared sensor enables a linear response to H2O2 concentrations of 1-90 µM. A low detection limit of 0.18 µM and a high sensitivity of 640 µA mM-1 cm-2 were obtained. These results indicate that the obtained sensors could potentially be applied in biomedical and environmental fields.


Assuntos
Nanotubos de Carbono , Cobalto/química , Técnicas Eletroquímicas/métodos , Eletrodos , Compostos Ferrosos , Peróxido de Hidrogênio/química , Nanotubos de Carbono/química , Ftalimidas
4.
Cardiol J ; 29(3): 432-440, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32207836

RESUMO

BACKGROUND: Numerous worldwide clinical trials have proven the indisputably negative influence of morphine on the pharmacokinetics and pharmacodynamics of P2Y12 receptor inhibitors in patients presenting with acute coronary syndromes. The aim of this trial was to evaluate whether oral coadministration of an anti-opioid agent, naloxone, can be considered a successful approach to overcome 'the morphine effect'. METHODS: Consecutive unstable angina patients receiving ticagrelor and morphine with or without orally administered naloxone underwent assessment of platelet reactivity using Multiplate analyzer as well as evaluation of the pharmacokinetic profile of ticagrelor and its active metabolite, AR-C124910XX, at 9 pre-defined time points within the first 6 hours following oral intake of the ticagrelor loading dose. RESULTS: The trial shows no significant differences regarding the pharmacokinetics of ticagrelor between both study arms throughout the study period. AR-C124910XX plasma concentration was significantly higher 120 min after the ticagrelor loading dose administration (p = 0.0417). However, the evaluation of pharmacodynamics did not show any statistically significant differences between the study arms. CONCLUSIONS: To conclude, this trial shows that naloxone co-administration in ticagrelor-treated acute coronary syndrome patients on concomitant treatment with morphine shows no definite superiority in terms of ticagrelor pharmacokinetic and pharmacodynamic profile.


Assuntos
Síndrome Coronariana Aguda , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/tratamento farmacológico , Humanos , Morfina/efeitos adversos , Naloxona , Entorpecentes , Inibidores da Agregação Plaquetária , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Ticagrelor
5.
Appl Surf Sci ; 524: 146602, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32382204

RESUMO

Phototherapies, including photodynamic therapy (PDT), have been widely used in the treatment of various diseases, especially for cancer. However, there is still a lack of effective, safe photosensitizers that would be well tolerated by patients. The combination of several methods (like phototherapy and hyperthermia) constitutes a modern therapeutic approach, which demands new materials based on components that are non-toxic without irradiation. Therefore, this study presents the synthesis and properties of novel, advanced nanomaterials in which the advantage features of the magnetic nanoparticles and photoactive compounds were combined. The primary purpose of this work was the synthesis of magnetic nanoparticles coated with biocompatible and antitumor polysaccharide - levan, previously unknown from scientific literature, and the deposition of potent photosensitizer - zinc(II) phthalocyanine on their surface. In order to better characterize the nature of the coating covering the magnetic core, the atomic force microscope analysis, a contact angle measurement, and the mechanical properties of pure levan and its blend with zinc(II) phthalocyanine films were investigated. This magnetic nanomaterial revealed the ability to generate singlet oxygen upon exposure to light. Finally, preliminary toxicity of obtained nanoparticles was tested using the Microtox® test - with and without irradiation.

6.
Med Chem ; 16(7): 848-859, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31340740

RESUMO

BACKGROUND: Reversed-phase liquid chromatography may cause difficulties, especially in the case of basic drugs due to the strong silanophilic interactions in the partition mechanism. Recently, imidazolium-based ionic liquids additives appeared interesting and a convenient solution for suppressing the harmful effect of free residuals of silanol groups, allowing remodeling of the stationary/mobile-phase system, and thus improving the lipophilicity assessment process. OBJECTIVE: The aim of the study was to evaluate the retention behavior of basic antipsychotics using various RP-LC systems, and compare them with data obtained from the modified ionic-liquids RP-TLC systems, and perform the QSRR analysis. METHODS: Retention and lipophilicity parameters of diverse antipsychotics have been examined in various RP-LC systems. Lipophilicity indices were compared with miscellaneous computed logP values. Furthermore, a large number of molecular descriptors have been computed and compared using various medicinal chemistry software, in order to contribute to the analysis of QSRR. RESULTS: Designated correlation coefficients showed that lipophilicity parameters from TLC systems without [EMIM][BF4] additive correlates very poor with the calculated logPs indices, whereas the indices from the traditional HPLC and TLC systems (with [EMIM][BF4]) were clearly better. Furthermore, QSRR analysis performed for these experimentally obtained lipophilicity parameters showed significant relationships between the retention constants (ROM, logkw) and the in silico calculated physicochemical molecular descriptors. CONCLUSION: ILs additive may be a significant factor affecting the lipophilicity of basic compounds, thus their use may be favorable in lipophilicity assessment studies. QSRR models with ILs showed that they may be useful in searching/or predicting HPLC/TLC retention parameters for the new/other antipsychotic drugs.


Assuntos
Antipsicóticos/análise , Líquidos Iônicos/química , Cromatografia de Fase Reversa , Cromatografia em Camada Fina , Interações Hidrofóbicas e Hidrofílicas
7.
Cardiol J ; 27(6): 780-788, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30799546

RESUMO

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) frequently occurs in the early phase of acute myocardial infarction (MI). Survivors require percutaneous coronary intervention (PCI) with concomitant dual antiplatelet therapy. Target temperature management, including mild therapeutic hypothermia (MTH), should be applied in comatose patients after resuscitation. However, an increased risk of stent thrombosis in patients undergoing hypothermia is observed. The aim of this study was to assess the impact of MTH on pharmacokinetics of ticagrelor in cardiac arrest survivors with MI treated with MTH and PCI. METHODS: In a prospective, observational, single-center study pharmacokinetics of ticagrelor were evaluated in 41 MI patients, including 11 patients after OHCA undergoing MTH (MTH group) and 30 MI patients without OHCA and MTH (no-MTH group). Blood samples were drawn before administration of a 180 mg ticagrelor loading dose, and 30 min, 1, 2, 4, 6, 12, and 24 h after the loading dose. RESULTS: In patients treated with MTH total exposure to ticagrelor during the first 12 h after the loading dose and maximal plasma concentration of ticagrelor were significantly lower than in the no-MTH group (AUC(0-12): 3403 ± 2879 vs. 8746 ± 5596 ng·h/mL, difference: 61%, p = 0.01; Cmax: 475 ± 353 vs. 1568 ± 784 ng/mL, p = 0.0002). Time to achieve maximal ticagrelor plasma concentration was also delayed in the MTH group (tmax for ticagrelor: 12 [6-24] vs. 4 [2-12] h, p = 0.01). CONCLUSIONS: Bioavailability of ticagrelor was substantially decreased and delayed in MI patients treated with MTH after OHCA. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02611934.


Assuntos
Hipotermia Induzida , Infarto do Miocárdio , Parada Cardíaca Extra-Hospitalar , Intervenção Coronária Percutânea , Disponibilidade Biológica , Humanos , Infarto do Miocárdio/terapia , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia , Inibidores da Agregação Plaquetária , Estudos Prospectivos , Ticagrelor , Resultado do Tratamento
8.
PLoS One ; 12(10): e0186013, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29023473

RESUMO

BACKGROUND: Data from available studies suggest that the presence of ST-elevation myocardial infarction (STEMI) may be associated with delayed and attenuated ticagrelor bioavailability and effect compared with non-ST-elevation myocardial infarction (NSTEMI). METHODS: In a single-center, prospective, observational trial 73 patients with myocardial infarction (STEMI n = 49, NSTEMI n = 24) underwent a pharmacokinetic and pharmacodynamic assessment after a 180 mg ticagrelor loading dose (LD). Ticagrelor and its active metabolite (AR-C124910XX) plasma concentrations were determined with liquid chromatography tandem mass spectrometry, and their antiplatelet effect was measured with the VASP assay and multiple electrode aggregometry. RESULTS: During the first six hours after ticagrelor LD, STEMI patients had 38% and 34% lower plasma concentration of ticagrelor and AR-C124910XX, respectively, than NSTEMI (ticagrelor AUC(0-6): 2491 [344-5587] vs. 3991 [1406-9284] ng*h/mL; p = 0.038; AR-C124910XX AUC(0-6): 473 [0-924] vs. 712 [346-1616] ng*h/mL; p = 0.027). STEMI patients also required more time to achieve maximal concentration of ticagrelor (tmax: 4.0 [3.0-12.0] vs. 2.5 [2.0-6.0] h; p = 0.012). Impaired bioavailability of ticagrelor and AR-C124910XX seen in STEMI subjects was associated with diminished platelet inhibition in this group, which was most pronounced during the initial hours of treatment. CONCLUSIONS: Plasma concentrations of ticagrelor and AR-C124910XX during the first hours after ticagrelor LD were one third lower in STEMI than in NSTEMI patients. This reduced and delayed ticagrelor bioavailability was associated with weaker antiplatelet effect in STEMI. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02602444 (November 09, 2015).


Assuntos
Adenosina/análogos & derivados , Infarto do Miocárdio sem Supradesnível do Segmento ST/tratamento farmacológico , Inibidores da Agregação Plaquetária/farmacocinética , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Adenosina/sangue , Adenosina/farmacocinética , Adenosina/farmacologia , Idoso , Disponibilidade Biológica , Plaquetas/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/sangue , Inibidores da Agregação Plaquetária/sangue , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Ticagrelor
9.
Eur J Cancer Prev ; 26(2): 131-134, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27222937

RESUMO

Prostate cancer is the leading type of cancer diagnosed in men. Serum prostate-specific antigen levels and digital rectal exam are far from perfect when it comes to differentiation of patients with prostate cancer and benign prostatic hyperplasia. In this study, we attempt to determine whether amino acids can be used as prostate cancer biomarkers. Concentrations of derivatized amino acids and amines were quantified by liquid chromatography tandem mass spectrometry. A total of 100 urine samples from the two groups including samples provided before and after prostate massage were examined quantitatively for amino acid and amine concentrations with 50 urine samples collected from cancer patients and 50 samples from patients diagnosed with benign prostatic hyperplasia. Arginine, homoserine, and proline were more abundant in urine samples of cancer patients compared with arginine, homoserine, and proline levels determined in urine collected from patients with benign growth. We also show that sarcosine is not a definitive indicator of prostate cancer when analyzed in urine samples collected either before or after prostate massage.


Assuntos
Aminoácidos/urina , Biomarcadores Tumorais/urina , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/urina , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/urina , Humanos , Masculino
10.
J Sep Sci ; 36(4): 665-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23355397

RESUMO

Iron is an essential element in human development. It is imperative for oxygen and electron transport and also for DNA and neurotransmitters synthesis. On the other hand, this metal is able to participate in Fenton's reaction that in turn leads to free radical damage. The most toxic fraction of iron - nontransferrin-bound iron and its part desferrioxamine-chelatable iron - can serve as an exquisite biomarker in the identification of iron imbalance. The goal of the present study was to devise a simple, repeatable, and inexpensive method for the determination of desferrioxamine-chelatable iron in serum blood samples. The assay procedure is based on desferrioxamine complex formation with iron ions followed to ferrioxamine and its quantitative measurement using RP-HPLC method. The desferrioxamine-chelatable iron was extracted from blood by centrifugation and SPE method. Chromatographic separation was performed at 40°C by step-form gradient elution using Cadenza CD-C18 column (150 × 4.6 mm id, particle size of 3.0 µm) connected with precolumn for contaminants removal. Gradient HPLC elution has been carried out with solvent A (10 mM Tris-HCl, pH 5.5) and solvent B (ACN). The flow rate was 1.2 mL/min, and the total separation time was 5 min. The linear quantitation range was 2.5-500 µM (r = 0.9973), and the LOD and LOQ were 0.42 and 1.29 µM, respectively. Proposed HPLC method allowed for the determination of desferrioxamine-chelatable iron fraction's of nontransferrin-bound iron, both in the buffer and the serum supplemented with iron ions as well as in the patients' serum samples with good results of precision and recovery. The developed method found to be sufficiently precise and reproducible for established conditions and after validation and may be used for routine assay of desferrioxamine-chelatable iron in biological samples.


Assuntos
Quelantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Desferroxamina/sangue , Ferro/sangue , Adulto , Quelantes/metabolismo , Desferroxamina/metabolismo , Feminino , Humanos , Masculino
11.
Anal Biochem ; 373(2): 313-21, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18047824

RESUMO

Heat shock protein 90 alpha (Hsp90alpha) was immobilized on aminopropyl silica via the N terminus to create the Hsp90alpha(NT) column or via the C terminus to create the Hsp90alpha(CT) column. Binding to the exposed C terminus on the Hsp90alpha(NT) column was characterized using frontal chromatography and the C-terminus ligands coumermycin A(1) (CA1) and novobiocin (NOVO). The calculated K(d) values were 220+/-110 nM (CA1) and 100+/-20 nM (NOVO). Nonlinear chromatography was used to determine the association and dissociation rate constants associated with the NOVO-Hsp90alpha complex: 22.2+/-8.8 microM(-1) s(-1) and 2.7+/-0.6s(-1), respectively. Binding to the exposed N terminus on the Hsp90alpha(CT) column was characterized using frontal chromatography. The K(d) values of the N-terminus ligands geldanamycin (GM, 90+/-50 nM), 17-allylamino-17-demethoxygeldanamycin (17-AAG, 210+/-50 nM), and radicicol (RAD, 20+/-9 nM) were consistent with previously reported values. The effect of the immobilization on ATPase activity was investigated through the determination of IC(50) values for inhibition of ATPase activity on the Hsp90alpha(CT) column. The IC(50) for GM was 2.80+/-0.18 microM, and the relative IC(50) values were 17-AAG>GM>RAD, in agreement with previously reported values and indicating that immobilization had not affected ATPase activity or sensitivity to inhibition.


Assuntos
Cromatografia Líquida/métodos , Proteínas de Choque Térmico HSP90/química , Adenosina Trifosfatases/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/isolamento & purificação , Concentração Inibidora 50 , Sistemas On-Line
12.
Biomed Chromatogr ; 19(1): 1-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15386567

RESUMO

The addition of an ionic liquid into the mobile phase appeared to be useful in optimization of chromatographic separation of peptides. Different behavior of peptides in thin-layer chromatography (TLC) was observed after addition of 1-ethyl-3-methylimidazolium tetra fluoroborate to the eluent in comparison to the system without the ionic liquid. Nonlinear dependence of the retention coefficient, R(M), of peptides on the volume percentage of acetonitrile in the eluent was found in normal-phase TLC with and without immidazolium tetra fluoroborate in the mobile phase. In general, R(M) increased with increasing concentration of acetonitrile. In TLC systems without the ionic liquid, R(M) can be described well with a quadratic function. On the other hand, in a TLC system with an ionic liquid as the additive to the mobile phase, the retention behavior is better described with a third-degree polynomial function. The potential usefulness of ionic liquids for optimization of separation of peptides was demonstrated. Optimization of the separation conditions was supported by a commercially available computer program.


Assuntos
Cromatografia em Camada Fina/métodos , Peptídeos/isolamento & purificação , Acetonitrilas , Simulação por Computador , Imidazóis/química , Oligopeptídeos/isolamento & purificação , Silanos/química
13.
Electrophoresis ; 25(20): 3450-4, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15490452

RESUMO

A capillary electrophoretic method for resolving selected imidazolium ionic liquid cations is reported. The method, in which citric buffer is used as the running electrolyte, is simple and reproducible. The separation of a standard mixture is in linear accordance with the relative molecular mass (M(r)) of solutes regardless of the type of substitution (alkyl or aryl). The theoretical prediction of compounds as yet not analyzed is therefore possible; however, cations with identical molecular masses are inseparable with this method. Nevertheless, the method's quantitative analytical performance was excellent. The paper also discusses the applicability of a method for tracking the photodegradation kinetics of an exemplary ionic liquid.


Assuntos
Eletroforese Capilar/métodos , Imidazóis/química , Cátions/análise , Cátions/isolamento & purificação , Concentração de Íons de Hidrogênio , Íons/química , Concentração Osmolar
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