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1.
Talanta ; 273: 125883, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38521023

RESUMO

Quercetin (QUE) is a powerful antioxidant and one of the common phenolic compounds found in plants, vegetables, and fruits, which has shown many pharmacological activities. The complex nature of the matrix in which QUE is found and its importance and potential uses in diverse applications force the researchers to develop selective and sensitive sensors. In the present work, a novel molecularly imprinted polymer (MIP)-based electrochemical sensor was fabricated for the selective and sensitive determination of the QUE in plant extracts and food supplements. Tryptophan methacrylate (TrpMA) was chosen as the functional monomer, whereas the photopolymerization (PP) method was applied using a glassy carbon electrode (GCE). Electrochemical and morphological characterizations of the developed sensor (TrpMA@QUE/MIP-GCE) were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). The linear range of the developed sensor was determined to be in the range of 1.0-25 pM, while the limit of detection (LOD) was calculated to be 0.235 pM. In conclusion, The TrpMA@QUE/MIP-GCE sensor might be classified as a promising platform for selective and sensitive determination of QUE not only in plant extracts but also in commercial food supplements because of its reliability, reproducibility, repeatability, stability, and fast response time.


Assuntos
Fragaria , Impressão Molecular , Rubus , Polímeros/química , Quercetina , Reprodutibilidade dos Testes , Metanol , Técnicas Eletroquímicas/métodos , Carbono/química , Limite de Detecção , Polímeros Molecularmente Impressos , Eletrodos , Extratos Vegetais
2.
Chem Biodivers ; 21(3): e202301645, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38235946

RESUMO

This study examines the potential of herniarin from tarragon, as an agent with multifaceted effects on bladder cancer cells and investigates herniarin's impact on cell viability, migration, cell cycle regulation, apoptosis induction, and Erk signaling pathways in bladder cancer cell lines, including RT-112 (grade 1, non-invasive), HTB9 (grade 2, invasive), and HT1376 (grade 3, invasive), through comprehensive in vitro experiments. The compound causes cell cycle arrest at distinct phases in different cell lines: G1/S arrest in RT112 cells, G2/M arrest in HTB9 cells, and S phase arrest in HT1376 cells. Furthermore, herniarin induces caspase-mediated apoptosis in various cell lines and simultaneously modulates protein levels of apoptotic and anti-apoptotic proteins, indicating its potential as a therapeutic agent. Herniarin's influence also extends to Erk signaling, a crucial pathway that regulates cell growth and differentiation. In conclusion, this study reveals herniarin's potential as a versatile agent in the treatment of bladder cancer.


Assuntos
Apoptose , Umbeliferonas , Neoplasias da Bexiga Urinária , Humanos , Sobrevivência Celular , Linhagem Celular Tumoral , Pontos de Checagem da Fase G2 do Ciclo Celular , Ciclo Celular , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Proliferação de Células , Pontos de Checagem do Ciclo Celular
3.
Chem Biodivers ; 20(8): e202300414, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37338138

RESUMO

In this study, methanol, ethanol, methanol-dichloromethane (1 : 1, v/v), acetone, ethyl acetate, diethyl ether, and chloroform extracts of lavender (Lavandula stoechas L. subsp. stoechas) were prepared by maceration, and the ursolic acid contents in the extracts were determined quantitatively by HPLC analyses. The present results show that the methanol-dichloromethane (1 : 1, v/v) solvent system is the most efficient solvent system for the extraction of ursolic acid from the plant sample with the highest yield (2.22 g/100 g plant sample). In the present study, a new practical method for the isolation of ursolic acid from polar extracts was also demonstrated for the first time. The inhibition effects of the extracts and ursolic acid were also revealed on α-glycosidase, acetylcholinesterase, butyrylcholinesterase, and human carbonic anhydrase I and II enzymes by determining IC50 values for the first time. The extracts and ursolic acid acted as potent antidiabetic agents by strongly inhibiting the α-glycosidase activity, whereas they were found to be very weak neuroprotective agents. In view of the present results, L. stoechas and its major metabolite, ursolic acid, can be recommended as a herbal source to control postprandial blood sugar levels and prevent diabetes by delaying the digestion of starch in food.


Assuntos
Lavandula , Óleos Voláteis , Triterpenos , Humanos , Óleos Voláteis/farmacologia , Metanol , Acetilcolinesterase , Butirilcolinesterase , Cloreto de Metileno , Triterpenos/farmacologia , Extratos Vegetais/farmacologia , Solventes , Glicosídeo Hidrolases , Ácido Ursólico
4.
Expert Opin Drug Metab Toxicol ; 19(5): 319-327, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37269349

RESUMO

BACKGROUND: Despite its advantages over other antipsychotics, for treatment-resistant schizophrenia, clinical use of Clozapine (CLZ) is challenging by its narrow therapeutic index and potentially life-threatening dose-related adverse effects. RESEARCH DESIGN AND METHODS: As the potential role in CLZ metabolism is assigned to CYP1A2 enzyme and consequently Cytochrome P450 oxidoreductase (POR) their genetic variations might help to determine CLZ levels in schizophrenia patients. For this purpose, 112 schizophrenia patients receiving CLZ were included in the current study. Plasma CLZ and N-desmethylclozapine (DCLZ) levels were analyzed by using HPLC and genetic variations were identified with the PCR-RFLP method. RESULTS: The patients' CYP1A2 and POR genotypes seemed to not affect plasma CLZ and DCLZ levels whereas in the subgroup analysis, POR *28 genotype significantly influenced simple and adjusted plasma CLZ and DLCZ levels concerning smoking habit and caffeine consumption. CONCLUSIONS: The findings of the present study highlight the importance of both genetic and non-genetic factors (smoking and caffeine consumption) for the individualization of the CLZ treatment. In addition to that, it suggests that the added utility of not only the CLZ metabolizing enzymes but also POR, which is crucial for proper CYP activity, to guide CLZ dosing might be useful for clinical decision-making.


Assuntos
Antipsicóticos , Clozapina , Esquizofrenia , Humanos , Clozapina/efeitos adversos , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Cafeína/efeitos adversos , Antipsicóticos/efeitos adversos , Estilo de Vida , Variação Genética
5.
J Biosci Bioeng ; 135(4): 313-320, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36828687

RESUMO

The detection of lactate is an important indicator of the freshness, stability, and storage stability of products as well as the degree of fermentation in the food industry. In addition, it can be used as a diagnostic tool in patients' healthcare since it is known that the lactate level in blood increases in some pathological conditions. Thus, the determination of lactate level plays an important role in not only the food industry but also in health fields. As a result, biosensor technologies, which are quick, cheap, and easy to use, have become important for lactate detection. In the current study, amperometric lactate biosensors based on lactate oxidase immobilization (with Nafion 5% wt) were designed and the limit of detection, linear range, and sensitivity values were determined to be 31 µM, 50-350 µM, and 0.04 µA µM-1 cm-2, respectively. Then, it was used for the measurement of lactic acid that produced by six different and morphologically identified presumptive lactic acid bacteria (LAB) which are isolated from different naturally fermented cheese samples. The biosensors were then used to successfully perform lactate measurements within 3 min for each sample, even though a few of them were out of the limit of detection. Thus, electrochemical biosensors should be used as an alternative and quick solutions for the measurement of lactate metabolites rather than the traditional methods which require long working hours. This is the first study to use a biosensor to measure lactate produced by foodborne LAB in a real sample.


Assuntos
Técnicas Biossensoriais , Ácido Láctico , Humanos , Ácido Láctico/metabolismo , Enzimas Imobilizadas/metabolismo , Técnicas Biossensoriais/métodos , Indústria Alimentícia , Fermentação
6.
Crit Rev Anal Chem ; 53(3): 498-519, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34601980

RESUMO

Chirality is an academically exciting and interesting topic, as most active ingredients have chirality. Chiral enantiomers with the same molecular shape show different effects from each other in terms of pharmacological, pharmacokinetic, and toxicology. There are many examples of these differences that have caused dramatic, even fatal damage. For these reasons, it is of great importance to developing an effective method to achieve chiral identification and separation, and chiral separation methods are becoming increasingly important in both the pharmaceutical industry and clinical studies. Electrochemical techniques, which can provide many advantages over other classical methods, have attracted great interest in chiral recognition in recent years. In this review, extensive and critical research of the trends in chiral recognition in recent studies is explained. Especially the role of cyclodextrins derivatives in chiral analysis has been investigated and the studies related to this are explained and given in the tables. In addition, some remarks and future perspectives in the field of chiral recognition are also discussed in the concluding part.


Assuntos
Ciclodextrinas , Medicina , Ciclodextrinas/química , Técnicas Eletroquímicas/métodos , Estereoisomerismo
7.
J Chromatogr A ; 1683: 463529, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36215920

RESUMO

In this article, a serially connected dual column liquid chromatography-tandem mass spectrometry (LC-MS/MS) method is described for the simultaneous separation and enantioseparation of proteinogenic amino acids. For this purpose, different achiral and chiral stationary phases (CSP) and mobile phase compositions have been tested. As a result of the optimization studies, the best enatioseparation for amino acids were achieved with a combination of zwitterionic and crown ether stationary phases using a gradient of two mobile phases: A (water:TFA 99.5:0.5, % v/v) and B (acetonitrile:ethanol:TFA 85:15:0.5, % v/v/v). The developed method provided simultaneous enantioseparation of all proteinogenic amino acids under this study including isomeric and isobaric ones except for proline. The method was successfully applied to human lung adenocarcinoma cells (A549) and healthy human lung epithelial cells (BEAS-2B) cultivated with d-amino acid containing cocktails in order to evaluate d-amino acids transfer rate in normal and cancer lines. Thed/l amino acid ratios were different in cancer and normal cell lines cultivated as mentioned above for aspartic acid, cysteine, methionine, phenylalanine, and serine.


Assuntos
Aminoácidos , Éteres de Coroa , Humanos , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão , Aminoácidos/química , Espectrometria de Massas em Tandem/métodos , Éteres de Coroa/química , Cisteína , Ácido Aspártico , Estereoisomerismo , Acetonitrilas/química , Aminas , Água/química , Prolina , Metionina , Fenilalanina , Serina , Etanol
8.
J Pharm Biomed Anal ; 219: 114966, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35908414

RESUMO

The aim of the present study is to develop the polymeric nanoparticulate drug delivery systems of piroxicam and to evaluate the in-vitro characteristics such as entrapment efficiency, surface morphology, in-vitro drug release performance, etc. For this reason, a novel HPLC methodology was developed for the determination of piroxicam from its bulk form, pharmaceutical preparation, and nanoparticulate delivery systems. Furthermore, the developed formulation was applied to the rats and the biological samples (plasma, liver, heart, spleen, kidney, and lung homogenates) were analyzed by the developed HPLC method following a salting-out assisted liquid-liquid extraction strategy for the first time in the literature. A Kinetex C18 analytical column (150 mm × 4.6 mm i.d., 5 µm) was used as a stationary phase with a 0.8 mL/min flow rate of acetonitrile: phosphate buffer (40:60, v/v), the column oven was adjusted to 40 °C and detection wavelength is set to 360 nm. Developed method were validated as per selectivity, linearity, LOD, LOQ, precision, and accuracy specified in the International Council for Harmonisation guidelines. As a result of the present study, it has been shown that the analysis of piroxicam from the bulk form, pharmaceutical preparation, developed polymeric-based drug delivery system, and biological samples can be successfully performed and no interferences were observed in any matrix. The developed method was also successfully utilized to study the tissue distribution of piroxicam in rats.


Assuntos
Extração Líquido-Líquido , Piroxicam , Animais , Cromatografia Líquida de Alta Pressão/métodos , Extração Líquido-Líquido/métodos , Preparações Farmacêuticas , Polímeros , Ratos
9.
Arch Microbiol ; 204(7): 432, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35759032

RESUMO

Honeybee products have been among important consumer products throughout history. Microbiota has attracted attention in recent years due to both their probiotic value and industrial potential. Fructophilic lactic acid bacteria (FLAB), whose field of study has been expanding rapidly in the last 20 years, are among the groups that can be isolated from the bee gut. This study aimed to isolate FLAB from the honeybees of two different geographic regions in Turkey and investigate their probiotic, metabolic and anti-quorum sensing (anti-QS) potential. Metabolic properties were investigated based on fructose toleration and acid and diacetyl production while the probiotic properties of the isolates were determined by examining pH, pepsin, pancreatin resistance, antimicrobial susceptibility, and antimicrobial activity. Anti-QS activities were also evaluated with the Chromobacterium violaceum biosensor strain. Two FLAB members were isolated and identified by the 16S rRNA analysis as Fructobacillus tropaeoli and Apilactobacillus kunkeei, which were found to be tolerant to high fructose, low pH, pepsin, pancreatin, and bile salt environments. Both isolates showed anti-QS activity against the C. violaceum biosensor strain and no diacetyl production. The daily supernatants of the isolates inhibited the growth of Enterococcus faecalis ATCC 29212 among the selected pathogens. The isolates were found resistant to kanamycin, streptomycin, erythromycin, and clindamycin. In the evaluation of the probiotic potential of these species, the negative effect of antibiotics and other chemicals to which honeybees are directly or indirectly exposed draws attention within the scope of the "One Health" approach.


Assuntos
Lactobacillales , Probióticos , Animais , Antibacterianos/farmacologia , Abelhas , Frutose/metabolismo , Lactobacillales/genética , Lactobacillus , Leuconostocaceae , Pancreatina , Pepsina A , RNA Ribossômico 16S/genética
10.
Cardiol Young ; 31(11): 1853-1857, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33977891

RESUMO

BACKGROUND AND OBJECTIVES: Total anomalous pulmonary venous connection is a rare cyanotic CHD that requires surgical repair. An unligated vertical vein after total anomalous pulmonary venous connection surgery may help to decrease the episodes of post-operative pulmonary hypertensive crises, low cardiac output syndrome, and mortality. The aim was to assess long-term outcome and our post-operative transcatheter vertical vein closure experiences in five patients with repaired total anomalous pulmonary venous connection patients. METHODS: A retrospective study was conducted in five cases with an unligated vertical vein following repair of supra-cardiac total anomalous pulmonary venous connection at our hospital from 2011 through 2018. Patients characteristics, cardiac catheterisation findings, surgical, and transcatheter procedural details were retrospectively analysed. RESULTS: Transcatheter closure of the unligated vertical vein was technically successful in all the patients. Procedure-related complications were not observed in any of the patients. No long-term complication was found. CONCLUSIONS: We suggest that transcatheter closure of the patent vertical vein is an effective and well-tolerated alternative to the surgical approach.


Assuntos
Veias Pulmonares , Síndrome de Cimitarra , Humanos , Ligadura , Veias Pulmonares/cirurgia , Estudos Retrospectivos , Síndrome de Cimitarra/diagnóstico por imagem , Síndrome de Cimitarra/cirurgia , Resultado do Tratamento
11.
Arch Microbiol ; 203(6): 3331-3339, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33866380

RESUMO

Interest in the production of exopolysaccharides by microorganisms has increased in the recent years. Using low-cost product is the main step of microbial production to reduce cost and compete with chemical production. In this work, EPS production of Streptococcus thermophilus isolates from yogurt (S2), kefir (S3), and S. thermophilus ATCC 19258 (S1) isolate which was used as control strains were investigated by using different fruit pulps. S. thermophilus isolates were identified by morphological and 16S sequence analysis. The amount of EPS obtained was measured spectrophotometrically using glucose as standard with phenol sulfuric acid method. All three isolates produced higher amounts of EPS on M17 medium than Nutrient medium. When the fruit pulp was added to the medium, EPS production increased in all three isolates. When different nitrogen sources were added together with fruit pulp juice, EPS production increased. The highest amount of EPS produced by ATCC 19258 strain (21.570 mg/L) and S3 isolate (29.131 mg/L) is the medium where mixed fruit pulp juice and nitrogen source is tryptophan. It has been shown that EPS production is increased by adding fruit pulps to the prepared media. It is thought that apricot pulp can be a good alternative in EPS production especially in the evaluation of wastes. Also, antiquorum sensing activity of the highest amount EPS was determined by using Chromobacterium violaceum CV026 strain and found effective on violacein pigment inhibition and C6-AHL production of biosensor strain.


Assuntos
Polissacarídeos Bacterianos/biossíntese , Streptococcus thermophilus/metabolismo , Chromobacterium/metabolismo , Chromobacterium/fisiologia , Meios de Cultura , Indóis/metabolismo , Percepção de Quorum , Streptococcus thermophilus/isolamento & purificação
12.
Molecules ; 25(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322449

RESUMO

In a recent study, opposite enantiomer elution order was observed for ketoprofen enantiomers on two amylose-phenylcarbamate-based chiral columns with the same chemical composition of the chiral selector but in one case with coated while in the other with an immobilized chiral selector. In the present study, the influence of this uncommon effect on method validation parameters for the determination of minor enantiomeric impurity in dexketoprofen was studied. The validated methods with two alternative elution orders for enantiomers were applied for the evaluation of enantiomeric impurity in six marketed dexketoprofen formulations from various vendors. In most of these formulations except one the content of enantiomeric impurity exceeded 0.1% (w/w).


Assuntos
Amilose/química , Cromatografia Líquida de Alta Pressão/métodos , Cetoprofeno/análogos & derivados , Fenilcarbamatos/química , Trometamina/química , Calibragem , Técnicas de Química Analítica , Química Farmacêutica , Cromatografia , Composição de Medicamentos , Contaminação de Medicamentos , Cetoprofeno/química , Limite de Detecção , Reprodutibilidade dos Testes , Estereoisomerismo
13.
J Sep Sci ; 43(17): 3491-3498, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32644279

RESUMO

Drug resistance is one of the main problems of cancer treatment. For this reason, combination therapy is commonly used for years. The combination of a chemotherapeutic, carboplatin, and the epigenetic drug decitabine is a new approach to modulate drug resistance. Nanoparticulate systems can overcome the drawbacks associated with the drug combinations. An analytical method that can detect and quantify carboplatin and decitabine which is encapsulated into the nanoparticles is necessary for nanoparticle development. In the literature, there is no analytical method in which carboplatin and decitabine are determined simultaneously. The primary purpose of this study is to develop and validate a novel, and stability-indicating high-performance liquid chromatography method for simultaneous determination of carboplatin and decitabine in pharmaceutical preparations in addition to developing the first nanoformulation for this drug combination. Therefore, various experimental parameters were optimized. The chromatographic separation was achieved using an XSelect® CSH C18 (250 × 4.6 mm I.D., 5 µm) column and a mobile phase consisting of methanol:water (containing 0.1% phosphoric acid) (3:97, v/v). The mobile phase pH was adjusted to 7.0 with 5 M NaOH. The developed method was successfully applied for the simultaneous determination and quantification of carboplatin and decitabine co-encapsulated in nanoparticles and released into in vitro dissolution medium.


Assuntos
Carboplatina/análise , Decitabina/análise , Nanopartículas/química , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos
14.
Z Naturforsch C J Biosci ; 75(11-12): 459-466, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-32598328

RESUMO

The aim of this study was to investigate the effects of extracts and pure Artemisia dracunculus L. (tarragon) metabolites on the antimonoamine oxidase and anticholinesterase activities. The compounds were characterized as stigmasterol (1), herniarin (2), (2E,4E)-1-(piperidin-1-yl)undeca-2,4-diene-8,10-diyn-1-one (3), (2E,4E)-N-isobutylundeca-2,4-dien-8,10-diynamide (4), 3,4-dehydroherniarin (5) and skimmin (6) by 1H-NMR, 13C-NMR, 1D and 2D NMR methods. The compounds 5 and 6 were isolated from tarragon for the first time. The extracts and pure compounds have inhibitory effects on the human monoamine oxidase (hMAO) A and B enzymes, whereas they did not exhibit any anticholinesterase activities. Among the tarragon compounds, only 2 and 6 compounds showed the inhibitory effects against hMAO A (IC50 = 51.76 and 73.47 µM, respectively) and hMAO B (IC50 = 0.84 and 1.63 mM, respectively). In the study, herniarin content in the extracts was also analysed by high-performance liquid chromatography and it was found that there was a relationship between the inhibition effects of the extracts and their herniarin content.


Assuntos
Artemisia/química , Cumarínicos/farmacologia , Monoaminoxidase/efeitos dos fármacos , Umbeliferonas/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Inibidores da Monoaminoxidase/farmacologia
15.
Cardiol Young ; 30(3): 318-322, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31910927

RESUMO

BACKGROUND: Psoriasis is a chronic inflammatory, multi-system disease that often begins in childhood and characterised by inflammatory skin, nails, scalp, and joint manifestations. The inflammation in psoriasis may promote some effect on the cardiac conduction system. OBJECTIVE: The aim of this study is to investigate myocardial repolarisation anomaly on the conducting system in the paediatric psoriasis using P wave dispersion, Tpeak-Tend interval, and Tp-e/QT ratio. METHODS: Forty-two patients diagnosed with psoriasis and 37 age- and sex-matched healthy children were enrolled in the study. Electrocardiographic parameters in psoriasis and control group were recorded from an electrocardiogram for each patient. RESULTS: The results indicated that the parameters including Pdis, QTc dis, Tp-e dis interval, and Tp-e max/QTmax ratios, which are known to be key indicators for the prediction of severe atrial or ventricular arrhythmia and sudden cardiac death and also important parameters used as the indicators for the non-invasive evaluation of the transmural heterogeneity were significantly longer in the study group compared to the control group (p < 0.05). CONCLUSIONS: This study includes the evidence linking psoriasis with increased myocardial repolarisation heterogeneity. These findings suggest that this patient population may be at an increased risk for arrhythmias. Our findings may be a basis for further studies.


Assuntos
Arritmias Cardíacas/etiologia , Sistema de Condução Cardíaco/fisiopatologia , Psoríase/complicações , Adolescente , Arritmias Cardíacas/diagnóstico , Estudos de Casos e Controles , Criança , Estudos Transversais , Eletrocardiografia , Feminino , Sopros Cardíacos/diagnóstico , Sopros Cardíacos/etiologia , Humanos , Masculino , Psoríase/fisiopatologia
16.
Arch Med Sci Atheroscler Dis ; 5: e320-e331, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34820545

RESUMO

INTRODUCTION: Compromise of tissue oxygenation during surgery is associated with increased mortality and morbidity in the postoperative period in patients with congenital cardiac disorders. It may be monitored with near-infrared spectroscopy (NIRS). We aimed to evaluate the tissue oxygenation and factors which may affect it by bilateral cerebral and somatic NIRS levels during cardiopulmonary bypass and to compare the NIRS values of cyanotic and acyanotic patient groups. MATERIAL AND METHODS: Two groups of patients with cyanotic and acyanotic congenital heart diseases were included in the study. Each group consisted of 15 patients between 0 and 5 years of age. All data were collected following anesthesia induction (T1), the 10th (T2) and 30th min (T3) of cardiopulmonary bypass (CPB), every 30 min during CPB (T4, T5, T6) and 1 h after (TS). Bilateral and somatic NIRS, blood gases, mean arterial pressure, and temperatures were recorded. RESULTS: Left and right somatic NIRS values in groups at all measurements did not differ significantly. Left and right cerebral NIRS values at T2 and T3 in cyanotic patients were significantly higher than in acyanotic patients. Mean arterial pressure and lactate levels at T1 and T3 measurements were responsible for left cerebral NIRS changes and mean arterial pressure on right cerebral NIRS values. CONCLUSIONS: Monitorization of tissue perfusion has critical importance during CPB of patients with congenital heart defects. Oxygenation may easily and reliably be measured with NIRS. Cerebral and somatic NIRS are more pronounced in cyanotic patients and cerebral NIRS is strongly associated with mean arterial pressure and circulating lactate levels.

17.
Electrophoresis ; 40(15): 1904-1912, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30900263

RESUMO

The major goal of this study was to determine the affinity pattern of brombuterol (BB) enantiomers toward various cyclodextrins (CD) and to evaluate the potential of NMR spectroscopy for understanding fine mechanisms of interactions between CDs and BB enantiomers. Separation of BB enantiomers was performed in a fused-silica capillary using a phosphate buffer, pH 2.5, at the room temperature in the normal polarity mode. It was shown once again that CE in combination with NMR spectroscopy represents a very sensitive tool for studies of affinity patterns and structure of CD complexes with chiral guests. Although opposite affinity patterns of BB enantiomers were observed toward native ß- and γ-CDs, no significant differences between the structures of the complexes of these two CDs with BB were detected by NMR spectroscopy. In contrary to this, the opposite affinity pattern of BB enantiomers toward ß-CD and its two sulfated derivatives, heptakis (2,3-O-diacetyl-6-sulfo)-ß-CD (HDAS-ß-CD) and heptakis (2-O-methyl-3,6-di-O-sulfo)-ß-CD (HMDS-ß-CD) was associated with major differences in the structure of the complexes. In addition, it was shown again that HMDS-ß-CD provides separation of enantiomers without formation of inclusion-type complex with the chiral analyte.


Assuntos
Compostos de Anilina/química , Compostos de Anilina/isolamento & purificação , Ciclodextrinas/química , Eletroforese Capilar/métodos , Etanolaminas/química , Etanolaminas/isolamento & purificação , Espectroscopia de Ressonância Magnética/métodos , Compostos de Anilina/análise , Etanolaminas/análise , Concentração de Íons de Hidrogênio , Estereoisomerismo
18.
Crit Rev Anal Chem ; 49(4): 306-323, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30595027

RESUMO

In the past decades, patients who have chemotherapy treatment have considerably increased number. At this point, the development of rapid precise, and reliable methods are very important to analyze cancer drugs from their dosage forms, animals or human biological samples. Among all the analytical methods, electrochemical methods hold an important position with their unique properties such as specificity in the biological recognition process, fast response, and their reliability and do not need a pretreatment process. Chromatographic methods are also used in a wide range of analytical applications for the analyses of anticancer drugs. The power of chromatography comes from its ability to separate a mixture of analytes and determination of their concentrations. Chromatographic techniques can mainly be divided into gas, liquid, and supercritical fluid chromatography. In the frame of this information, this review is aimed to provide basic principles of electroanalytical and high-performance liquid chromatography methods for the analysis of cancer drugs. In addition, some selected applications for electrochemistry-related techniques and high-performance liquid chromatography, for the determination of anti-cancer pharmaceuticals published in the last five years are also discussed.


Assuntos
Antineoplásicos/análise , Animais , Cromatografia Líquida , Humanos
19.
J Chromatogr A ; 1571: 231-239, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30093095

RESUMO

The affinity pattern of terbutaline enantiomers towards various cyclodextrins was studied using capillary electrophoresis. The affinity pattern of terbutaline enantiomers was the same towards all studied cyclodextrins except heptakis(2-O-methyl-3,6-di-O-sulfo)-ß-CD. Nuclear magnetic resonance spectroscopy was used for understanding of fine structural mechanisms of interactions of ß-cyclodextrin and its two sulfated derivatives with the enantiomers of terbutaline. The structure of terbutaline complexes with all 3 cyclodextrins studied was different from each other. In confirmation with our earlier studies it was shown again that capillary electrophoresis represents very sensitive technique for studies of affinity patterns in cyclodextrin complexes with chiral guests. Other instrumental (e.g. NMR spectroscopy and X-ray diffraction analysis) and theoretical techniques, although very useful for obtaining the information regarding the stoichiometry, binding constants and structure of intermolecular complexes, as well as about the forces involved in selector-selectand binding and chiral recognition, may sometimes fail to properly sense those fine differences in the affinity patterns. Therefore, it is recommended to use capillary electrophoresis in order to examine correctness of affinity pattern determined for intermolecular complexes of cyclodextrins with guest molecules by other instrumental or computation techniques.


Assuntos
Ciclodextrinas/química , Eletroforese Capilar/métodos , Terbutalina/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Estereoisomerismo , Terbutalina/isolamento & purificação
20.
J Chromatogr A ; 1571: 132-139, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30098733

RESUMO

Our earlier studies have demonstrated the applicability of polysaccharide-based chiral selectors in combination with superficially porous (or core-shell) silica (SPS) particles for the preparation of highly efficient chiral stationary phases (CSP). In earlier studies, CSPs were prepared by coating (adsorption) of the chiral selector onto the surface of silica. In this study we report for the first time the CSP obtained by covalent immobilization of a chiral selector onto the surface of SPS particles. The applicability of this CSP for the separation of enantiomers in pure methanol and acetonitrile, as well as in n-hexane/2-propanol mobile phases is shown. The effect of the injected sample amount, mobile phase flow rate and detection frequency on separation performance were studied, as well as high efficiency separation of enantiomers with the analysis time less than 30 s was attempted.


Assuntos
Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Dióxido de Silício/química , Benzamidas/química , Polissacarídeos/química , Porosidade , Estereoisomerismo
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