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1.
Chem Biodivers ; 21(3): e202301645, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38235946

RESUMEN

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.


Asunto(s)
Apoptosis , Umbeliferonas , Neoplasias de la Vejiga Urinaria , Humanos , Supervivencia Celular , Línea Celular Tumoral , Puntos de Control de la Fase G2 del Ciclo Celular , Ciclo Celular , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/metabolismo , Proliferación Celular , Puntos de Control del Ciclo Celular
2.
Chem Biodivers ; 20(8): e202300414, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37338138

RESUMEN

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.


Asunto(s)
Lavandula , Aceites Volátiles , Triterpenos , Humanos , Aceites Volátiles/farmacología , Metanol , Acetilcolinesterasa , Butirilcolinesterasa , Cloruro de Metileno , Triterpenos/farmacología , Extractos Vegetales/farmacología , Solventes , Glicósido Hidrolasas , Ácido Ursólico
3.
Arch Microbiol ; 204(7): 432, 2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35759032

RESUMEN

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.


Asunto(s)
Lactobacillales , Probióticos , Animales , Antibacterianos/farmacología , Abejas , Fructosa/metabolismo , Lactobacillales/genética , Lactobacillus , Leuconostocaceae , Pancreatina , Pepsina A , ARN Ribosómico 16S/genética
4.
Arch Microbiol ; 203(6): 3331-3339, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33866380

RESUMEN

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.


Asunto(s)
Polisacáridos Bacterianos/biosíntesis , Streptococcus thermophilus/metabolismo , Chromobacterium/metabolismo , Chromobacterium/fisiología , Medios de Cultivo , Indoles/metabolismo , Percepción de Quorum , Streptococcus thermophilus/aislamiento & purificación
5.
Cardiol Young ; 31(11): 1853-1857, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33977891

RESUMEN

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.


Asunto(s)
Venas Pulmonares , Síndrome de Cimitarra , Humanos , Ligadura , Venas Pulmonares/cirugía , Estudios Retrospectivos , Síndrome de Cimitarra/diagnóstico por imagen , Síndrome de Cimitarra/cirugía , Resultado del Tratamiento
6.
J Sep Sci ; 43(17): 3491-3498, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32644279

RESUMEN

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.


Asunto(s)
Carboplatino/análisis , Decitabina/análisis , Nanopartículas/química , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos
7.
Cardiol Young ; 30(3): 318-322, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31910927

RESUMEN

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.


Asunto(s)
Arritmias Cardíacas/etiología , Sistema de Conducción Cardíaco/fisiopatología , Psoriasis/complicaciones , Adolescente , Arritmias Cardíacas/diagnóstico , Estudios de Casos y Controles , Niño , Estudios Transversales , Electrocardiografía , Femenino , Soplos Cardíacos/diagnóstico , Soplos Cardíacos/etiología , Humanos , Masculino , Psoriasis/fisiopatología
8.
Molecules ; 25(24)2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33322449

RESUMEN

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).


Asunto(s)
Amilosa/química , Cromatografía Líquida de Alta Presión/métodos , Cetoprofeno/análogos & derivados , Fenilcarbamatos/química , Trometamina/química , Calibración , Técnicas de Química Analítica , Química Farmacéutica , Cromatografía , Composición de Medicamentos , Contaminación de Medicamentos , Cetoprofeno/química , Límite de Detección , Reproducibilidad de los Resultados , Estereoisomerismo
9.
Electrophoresis ; 40(15): 1904-1912, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30900263

RESUMEN

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.


Asunto(s)
Compuestos de Anilina/química , Compuestos de Anilina/aislamiento & purificación , Ciclodextrinas/química , Electroforesis Capilar/métodos , Etanolaminas/química , Etanolaminas/aislamiento & purificación , Espectroscopía de Resonancia Magnética/métodos , Compuestos de Anilina/análisis , Etanolaminas/análisis , Concentración de Iones de Hidrógeno , Estereoisomerismo
10.
Microb Pathog ; 121: 190-197, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29807134

RESUMEN

Studies conducted in recent years show that pathogen bacteria are not asocial assets and they use the cell to cell communication mechanism called quorum sensing that depends on population density to adapt changing environmental conditions. This mechanism is coordinate gene expression of various bacterial factors like bioluminescence, antibiotic biosynthesis, plasmid conjugation and virulence. Bacteria communicate with each other by producing signal molecules and regulate the production of virulence factors that have importance in the pathogenity formation. Virulence mechanisms of Pseudomonas aeruginosa, which causes various types of infections in humans, are also regulated by quorum sensing. Nowadays, biotechnological researches are focused on the development of homoserine lactone antagonists. The use of these type of molecules are considered to be a new treatment approach for blocking communication between bacteria and reducing virulence, therefore improving infection control. In this study, lactic acid of a potential probiotic Pediococcus acidilactici M7 strain isolated from newborn faeces was used to evaluate the inhibitory effect on quorum sensing signal molecules and some virulence factors of clinical Pseudomonas aeruginosa isolates. Results showed that lactic acid has an inhibitory effect on short-chain HSL production and swarming-swimming-twitching motility, elastase, protease, pyocyanin, and biofilm production of Pseudomonas aeruginosa isolates in certain quantities that are regulated by the quorum sensing system.


Asunto(s)
Pediococcus acidilactici , Probióticos , Pseudomonas aeruginosa/patogenicidad , Percepción de Quorum , 4-Butirolactona/análogos & derivados , 4-Butirolactona/antagonistas & inhibidores , 4-Butirolactona/metabolismo , Biopelículas/efectos de los fármacos , Heces/microbiología , Glucolípidos/metabolismo , Humanos , Recién Nacido , Ácido Láctico/metabolismo , Elastasa Pancreática/antagonistas & inhibidores , Elastasa Pancreática/metabolismo , Inhibidores de Proteasas/metabolismo , Piocianina/antagonistas & inhibidores , Piocianina/metabolismo , Factores de Virulencia/metabolismo
11.
Chirality ; 30(6): 807-815, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29637614

RESUMEN

A selective and sensitive stability indicting HPLC method was developed for the analysis of enantiomers of miconazole. For this purpose, six different polysaccharide-based chiral columns were evaluated. Optimization was performed using several polar organic and alcohol-hydrocarbon mobile phases. As a result of optimization studies, the analysis was carried out using Lux Cellulose-3, methanol as a mobile phase at a flow rate of 1 mL·min-1 , and the detection wavelength was arranged to 230 nm. Developed method has been fully validated according to International Council on Harmonization guidelines. Method was found linear in the concentration range of 1 to 200 µg·mL-1 . Coefficient of determination (R2 ) was calculated as 0.9996, intraday precision of the method was found with the RSD% of 0.56, and the recovery of the method was calculated close to 100%. Furthermore, some other validation parameters like specificity, selectivity, LOD, and LOQ were also investigated. Stability indicating capability of this method was shown by forced degradation studies, and the run time for each analysis was less than 6 minutes. As a result, simple, fast, reliable HPLC method was developed for the separation and determination of the enantiomers of miconazole. Applicability of the developed method was shown with the application of marketed pharmaceutical preparations.

12.
Biomed Chromatogr ; 32(4)2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29216682

RESUMEN

A combination of antiretroviral agents is frequently used in effective treatment of the human immunodeficiency virus infection. In this study, two different separation methods are presented for the simultaneous determination of emtricitabine, rilpivirine and tenofovir from raw materials and urine samples. Developed liquid chromatography and capillary electrophoresis methods were thoroughly optimized for high analytical performances. Optimization of multiple variables at the same time by performing a minimum number of experiments was achieved by the Box-Behnken design, which is an experimental design in response surface methodology, in capillary electrophoresis. The results of the experimental design ensure minimum analysis time with well-separated analytes. Separation conditions, such as different stationary phases, pH level, organic modifiers and temperatures in liquid chromatography method, were also optimized. In particular, among stationary phases, the core-shell column especially enhanced the effectiveness of separation in liquid chromatography. Both methods were fully validated and applied to real samples. The main advantage of the developed methods is the separation of the drug combination in a short time with high efficiency and without any time-consuming steps.


Asunto(s)
Antirretrovirales/orina , Cromatografía Liquida/métodos , Electroforesis Capilar/métodos , Emtricitabina/orina , Rilpivirina/orina , Tenofovir/orina , Antirretrovirales/química , Antirretrovirales/aislamiento & purificación , Emtricitabina/química , Emtricitabina/aislamiento & purificación , Humanos , Límite de Detección , Modelos Lineales , Modelos Estadísticos , Reproducibilidad de los Resultados , Rilpivirina/química , Rilpivirina/aislamiento & purificación , Tenofovir/química , Tenofovir/aislamiento & purificación
13.
Electrophoresis ; 35(19): 2833-41, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24810231

RESUMEN

One-dimensional dynamic computer simulation was employed to investigate the separation and migration order change of ketoconazole enantiomers at low pH in presence of increasing amounts of (2-hydroxypropyl)-ß-cyclodextrin (OHP-ß-CD). The 1:1 interaction of ketoconazole with the neutral cyclodextrin was simulated under real experimental conditions and by varying input parameters for complex mobilities and complexation constants. Simulation results obtained with experimentally determined apparent ionic mobilities, complex mobilities, and complexation constants were found to compare well with the calculated separation selectivity and experimental data. Simulation data revealed that the migration order of the ketoconazole enantiomers at low (OHP-ß-CD) concentrations (i.e. below migration order inversion) is essentially determined by the difference in complexation constants and at high (OHP-ß-CD) concentrations (i.e. above migration order inversion) by the difference in complex mobilities. Furthermore, simulations with complex mobilities set to zero provided data that mimic migration order and separation with the chiral selector being immobilized. For the studied CEC configuration, no migration order inversion is predicted and separations are shown to be quicker and electrophoretic transport reduced in comparison to migration in free solution. The presented data illustrate that dynamic computer simulation is a valuable tool to study electrokinetic migration and separations of enantiomers in presence of a complexing agent.


Asunto(s)
Ciclodextrinas/química , Electroforesis/métodos , Modelos Químicos , Estereoisomerismo , Simulación por Computador , Cetoconazol/química , Cetoconazol/aislamiento & purificación
14.
Biomed Chromatogr ; 28(10): 1409-17, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24861889

RESUMEN

Fulvestrant is used for the treatment of hormone receptor-positive metastatic breast cancer in postmenopausal women with disease progression following anti-estrogen therapy. Several reversed-phase columns with variable silica materials, diameters, lengths, etc., were tested for the optimization study. A good chromatographic separation was achieved using a Waters X-Terra RP(18) column (250 × 4.6 mm i.d. × 5 µm) and a mobile phase, consisting of a mixture of acetonitrile-water (65:35; v/v) containing phosphoric acid (0.1%). The separation was carried out 40 °C with detection at 215 nm.The calibration curves were linear over the concentration range between 1.0-300 and 1.0-200 µg/mL for standard solutions and biological media, respectively. The proposed method is accurate and reproducible. Forced degradation studies were also realized. This fully validated method allows the direct determination of fulvestrant in dosage form and biological samples. The average recovery of the added fulvestrant amount in the samples was between 98.22 and 104.03%. The proposed method was also applied for the determination of fulvestrant from the polymeric-based nanoparticle systems. No interference from using polymers and other excipients was observed in in vitro drug release studies. Therefore an incorporation efficiency of fulvestrant-loaded nanoparticle could be determined accurately and specifically.


Asunto(s)
Cromatografía de Fase Inversa/métodos , Estradiol/análogos & derivados , Nanopartículas/química , Estradiol/análisis , Estradiol/química , Estradiol/farmacocinética , Fulvestrant , Humanos , Cinética , Ácido Láctico , Límite de Detección , Modelos Lineales , Polietilenglicoles , Poliglactina 910 , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Reproducibilidad de los Resultados
15.
Talanta ; 273: 125883, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38521023

RESUMEN

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.


Asunto(s)
Fragaria , Impresión Molecular , Rubus , Polímeros/química , Quercetina , Reproducibilidad de los Resultados , Metanol , Técnicas Electroquímicas/métodos , Carbono/química , Límite de Detección , Polímeros Impresos Molecularmente , Electrodos , Extractos Vegetales
16.
J Enzyme Inhib Med Chem ; 28(6): 1143-55, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22994658

RESUMEN

Melatonin (MLT) is a strong free-radical scavenger, which protects the body from the effects of oxidants. In recent years, MLT have been described resulting in much attention in the development of synthetic compounds possessing. As a part of our ongoing study a series of indole-based MLT analogue hydrazide/hydrazone derivatives were synthesized, characterized and in vitro antioxidant activity was investigated by evaluating their reducing effect against oxidation of a redox sensitive fluorescent probe. Membrane stabilizing effect of all compounds was also investigated by lactate dehydrogenase leakage assay. Furthermore voltammetric methods have been applied to the synthesized compounds to characterize oxidation potentials to get insight into their metabolism owing to the oxidation mechanisms taking place at the electrode and in the body share similar principles.


Asunto(s)
Antioxidantes/química , Antioxidantes/metabolismo , Técnicas Electroquímicas , Eritrocitos/química , Indoles/química , Melatonina/análogos & derivados , Melatonina/metabolismo , Antioxidantes/síntesis química , Electrodos , Eritrocitos/metabolismo , Colorantes Fluorescentes , Humanos , Hidroliasas/metabolismo , Melatonina/síntesis química , Melatonina/química , Estructura Molecular
17.
J AOAC Int ; 96(4): 751-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24000747

RESUMEN

A stability-indicating RP-LC assay method was developed for the simultaneous determination of the cardiovascular drugs amlodipine and perindopril in the presence of degradation products generated from forced decomposition studies. The developed method is applicable for the determination of related substances in bulk drugs and simultaneous assay in a tablet pharmaceutical dosage form. Separation of the drugs and their degradation products was obtained using an RP Waters Spherisorb ODS1 column (250 x 4.6 mm id, 5 pm particle size) with the mobile phase acetonitrile-water (30 + 70, v/v) containing 15 mM phosphoric acid. The pH of the mobile phase was adjusted to 5.0. A flow rate of 1.2 mL/min was used for the separations, with detection at 215 nm. The chromatographic separation was performed at a column temperature of 45 degrees C. Atenolol was chosen as the internal standard. Amlodipine and perindopril were exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions, and the stressed samples were analyzed by the proposed method. Degradation studies showed that both compounds were degraded under these stress conditions. The method was found to be stability-indicating and can be used for the routine analysis of amlodipine and perindopril in the studied combined tablet dosage form.


Asunto(s)
Amlodipino/análisis , Antihipertensivos/análisis , Cromatografía Liquida/métodos , Perindopril/análisis , Estabilidad de Medicamentos , Límite de Detección , Comprimidos/química
18.
J AOAC Int ; 96(1): 42-51, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23513956

RESUMEN

Voltammetric, chromatographic, and spectrophotometric methods were developed for the simultaneous determination of bisoprolol fumarate (BIS) and hydrochlorothiazide (HCZ). Differential pulse and square wave voltammetry techniques were used to analyze BIS and HCZ simultaneously by measuring at about 1400 and 1100 mV, respectively. RP-HPLC was the second method for simultaneous analysis of the compounds. The mixture of BIS, HCZ, and moxifloxacin as an internal standard was separated on an RP Zorbax Eclipse XDB-C18 column (150 x 4.6 mm, id, 5 microm particle size) using acetonitrile-15 mM phosphate (25+75, v/v) mobile phase at a 1.0 mL/min flow rate. The third method was based on first derivative of the ratio-spectra method obtained from the measurements of the amplitudes at 246 and 257 nm for BIS and HCZ, respectively. All the proposed methods were effectively applied for the simultaneous determination of BIS and HCZ in tablet dosage forms without any time-consuming extraction, sample preparation, or derivatization procedures.


Asunto(s)
Antihipertensivos/análisis , Bisoprolol/análisis , Hidroclorotiazida/análisis , Cromatografía Líquida de Alta Presión , Espectrofotometría , Comprimidos
19.
Crit Rev Anal Chem ; 53(3): 498-519, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34601980

RESUMEN

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.


Asunto(s)
Ciclodextrinas , Medicina , Ciclodextrinas/química , Técnicas Electroquímicas/métodos , Estereoisomerismo
20.
J Biosci Bioeng ; 135(4): 313-320, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36828687

RESUMEN

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.


Asunto(s)
Técnicas Biosensibles , Ácido Láctico , Humanos , Ácido Láctico/metabolismo , Enzimas Inmovilizadas/metabolismo , Técnicas Biosensibles/métodos , Industria de Alimentos , Fermentación
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