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1.
Molecules ; 29(6)2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38542873

RESUMEN

Type 2 diabetes mellitus is a multifactorial disorder whose primary manifestation usually initiates with elevated blood sugar levels. Several antidiabetic agents are used to manage type 2 diabetes mellitus, of which empagliflozin is an oral sodium-glucose co-transporter (SGLT-2) inhibitor in the kidney. This research aims to develop and validate a simple analytical method for determining empagliflozin levels in biological fluid and to further evaluate grapefruit juice's impact on empagliflozin pharmacokinetics in rats. High-Performance Liquid Chromatography (HPLC) was used to establish a simple, rapid, and accurate method for determining empagliflozin levels in rat plasma, in the presence of grapefruit juice. Four groups of rats (n = 10 rats in each) were used in the preclinical study. Group A (healthy rats) received empagliflozin alone; Group B (healthy rats) received empagliflozin with grapefruit; Group C (diabetic rats) received empagliflozin with grapefruit; and Group D (healthy, negative control) received no medication. The rats (n = 10) were given grapefruit juice instead of water for seven days before receiving the empagliflozin dose (0.16 mg/kg). Some pharmacokinetic parameters for each group were determined. The maximum plasma concentration (Cmax) and area under the curve (AUC) of empagliflozin in Group A without grapefruit intake were 730 ng/mL and 9264.6 ng × h/mL, respectively, with Tmax (2 h). In Group B, Cmax was 1907 ng/mL and AUC was 10,290.75 ng × h/mL in the presence of grapefruit, with Tmax (1 h); whereas, in Group C, the Cmax was 2936 ng/mL and AUC was 18657 ng × h/mL, with Tmax (2 h). In conclusion, our results showed that the co-administration of grapefruit with empagliflozin should be cautiously monitored and avoided, in which grapefruit elevates the plasma level of empagliflozin. This may be attributed to the inhibition of the uridine enzyme in the grapefruit by hesperidin, naringin, and flavonoid.


Asunto(s)
Compuestos de Bencidrilo , Citrus paradisi , Citrus , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Glucósidos , Ratas , Animales , Cromatografía Líquida de Alta Presión , Citrus/química , Bebidas , Área Bajo la Curva
2.
Pharmaceuticals (Basel) ; 17(3)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38543065

RESUMEN

The two main classifications of antidepressant medications are selective norepinephrine reuptake inhibitors (SNRIs) and selective serotonin reuptake inhibitors (SSRIs). Out of the available choices, selective serotonin reuptake inhibitors (SSRIs) have emerged as the most commonly prescribed option. The class demonstrates a greater degree of diversity in its structural characteristics in contrast to its neurochemical effects. Nevertheless, it is important to acknowledge that the chemical composition of a drug within this specific class does not carry substantial significance in the selection process. A comprehensive analysis of the pharmacodynamic and pharmacodynamic properties of antidepressant drugs proves advantageous for clinicians and managed care providers responsible for selecting preferred selective serotonin reuptake inhibitors (SSRIs) from a roster of authorized medications. The physicochemical characteristics, which possess considerable significance, are frequently disregarded except during the drug development stage. Pharmacodynamic properties refer to the physiological and biochemical effects that drugs exert on the human body. It is noteworthy that the inclusion of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) in a comprehensive depression management protocol may demonstrate enhanced effectiveness in clinical environments as opposed to controlled trials.

3.
J Adv Pharm Technol Res ; 15(1): 1-7, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38389974

RESUMEN

Type 2 diabetes is common globally. Pioglitazone (PGZ) is an oral TZD antidiabetic, whereas chromium-picolinate (Cr-PL) and Cr-glucose tolerance factor (Cr-GTF) are useful type 2 diabetes mellitus (T2DM) supplements. Cr-PL/GTF antioxidants cure T2DM. They may fail in diabetes with or without insulin-sensitizing medications. It examined how Cr-PL, Cr-GTF, PGZ, and their combination affected glucose, glycosylated hemoglobin, insulin, and HOMA-IR. Sixty-three adult Sprague-Dawley rats (220-300 g) were selected, and nine rats were randomly assigned to a normal nondiabetic group. In contrast, 54 rats were randomly split into 9 rats per each of the 6 major groups and injected intraperitoneally with 40 mg/kg STZ to induce T2DM. Rats were administered PGZ = 0.65 mg/kg (rat weight)/day, Cr-PL = 1 mg/kg, Cr-GTF = 1 mg/kg, and their combinations (PGZ + Cr-PL and Cr-GTF) daily for 6 weeks per intervention. The PGZ + Cr-PL and PGZ + Cr-GTF groups had substantially lower insulin levels than the PGZ group (13.38 ± 0.06, 12.98 ± 0.19 vs. 14.11 ± 0.02, respectively), with the PGZ + Cr-GTF group having the lowest insulin levels (12.98 ± 0.19 vs. 14.11 ± 0.02, 13.38±0.06, respectively). Intervention substantially reduced HOMA-IR in the PZ + Cr-PL and PZ + Cr-GTF groups compared to PGZ (7.49 ± 0.04, 6.69 ± 0.11 vs. 8.37 ± 0.04, respectively). This research found that combining PGZ with Cr-GTF resulted in considerably lower HOMA-IR levels than the PGZ and Cr-PL groups (6.69 ± 0.11 vs. 8.37 ± 0.04, 7.49 ± 0.04, respectively). Both Cr-PL and Cr-GTF may control T2DM. Both Cr complexes improved T2DM biomarkers more than the control diabetic group without medication. PGZ alone and PGZ + Cr-PL had less pharmacological synergy than Cr-GTF and PGZ in altering insulin and HOMA-IR blood levels. These encouraging discoveries need more study.

4.
J Mass Spectrom ; 58(12): e4984, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37950646

RESUMEN

Ribociclib is a cyclin-dependent kinase (CDK4/6) inhibitor and is a standard of care for treating metastatic breast cancer. The drug has moderate oral bioavailability and exhibits permeability-controlled absorption. Novel formulations to enhance ribociclib pharmacokinetics are being developed and tested in rats. This requires developing analytical assays for quantifying ribociclib monitoring in rat plasma. We present a fully validated, sensitive, and simple LC-MS/MS method for measuring ribociclib in rat plasma. Ribociclib-D6 was utilized as an internal standard, and a simple protein precipitation procedure with acetonitrile was used in sample preparation. Excellent assay linearity was observed over a standard curve concentration of 1.008-1027.624 ng/mL. Acceptable intra- and inter-day accuracy and reproductivity were demonstrated for ribociclib quality controls (bias and CV% within ±15%). Complete extraction recovery of ribociclib was achieved, and a negligible matrix effect of analyte to internal standard ratio was observed. Ribociclib was stable at various conditions, including bench-top, freeze-thaw, and short-term stability. Overall, the presented method is simple, sensitive, accurate, and precise and was successfully applied to quantify ribociclib in plasma samples from a pharmacokinetic study of ribociclib suspension and nanoparticle formulation in rats.


Asunto(s)
Aminopiridinas , Espectrometría de Masas en Tándem , Ratas , Animales , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Aminopiridinas/farmacocinética , Purinas/farmacocinética , Reproducibilidad de los Resultados
5.
J Chromatogr Sci ; 2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37622601

RESUMEN

N-nitrosamine pollutants are probable carcinogens. Regulatory agencies declared their presence in the drugs unsafe for human consumption and demanded their recall. Using ultra-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry (UPLC-APCI-MS/MS) in tablet dosage form based on International Conference on Harmonization (ICH) tripartite guideline criteria, we aim to develop and test a new approach for identifying and validating nitrosamine-contaminants, N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) in irbesartan, olmesartan and metformin. The column was Phenomenex Luna-C18, 100 × 3.0 mm and 3.0 µm. A mobile gradient phase of formic acid in either water or methanol separated the impurities. NDMA and NDEA had retention times of 0.85 and 2.55 min, respectively. The detector's linearity was established at concentrations ranging from 0.6 to 100 ng/mL. R2 for NDMA and NDEA were 0.9996 and 0.9998, respectively, with a linear response function established at 0.6-100 ng/mL. Limit of detection and limit of quantification for NDMA and NDEA were 0.35, 0.29 and 0.55, 0.37 ng/mL, respectively. On average, recovery rates for NDMA and NDEA ranged from 96.0 to 98.4 and 96.2 to 98.0%, respectively. The relative standard deviation for NDMA and NDEA was 3.46 and 2.69, respectively. According to the ICH guidelines, the developed method was quick, sensitive and valid. The pharmaceutical formulations of irbesartan, olmesartan and metformin may be regularly examined using the approach provided here.

6.
Polymers (Basel) ; 15(13)2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37447489

RESUMEN

Ribociclib is a newly approved orally administered drug for breast cancer. This study aimed to prepare, characterize, and evaluate hybrid lipid-polymer nanoparticles (PLNs) of ribociclib to enhance its in vitro dissolution rate, pharmacokinetics, and anticancer efficacy. Ribociclib-loaded PLNs were prepared by solvent evaporation using the Box-Behnken design to optimize formulation variables. Particle size, entrapment efficiency, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), in vitro release cytotoxicity, molecular modeling, and pharmacokinetic studies were examined. The ribociclib-loaded PLN (formula 1, F1) was optimized in terms of particle size (266.9 ± 4.61 nm) and encapsulation efficiency (59.1 ± 2.57 mg/mL). DSC and thermogravimetric characterization showed the absence of a crystalline structure in the prepared PLNs, confirmed by FTIR, and showed no interactions between the components and the drug. AFM showed well-dispersed heterogeneously shaped nanoparticles. The in vitro release profile exhibited significant results for the optimized formula, reaching 100% at 600 and 90 min at pH 6.8 and 1.2, respectively. The low IC50 obtained by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay suggests that optimized PLN might serve as an effective delivery vehicle for cancer treatment, especially breast and lung cancer. Molecular modeling revealed several hydrogen bonds. A pharmacokinetic study in rats showed that the ribociclib formula had a 6.5-fold increase in maximum concentration (Cmax) and a 5.6-fold increase in area under the curve (AUC). Regarding the everted intestinal sac absorption, formula 1 increased ribociclib penetration relative to the physical combination and pure medication. In conclusion, optimized PLNs with enhanced physicochemical and cytotoxic properties and improved pharmacokinetic parameters were successfully prepared.

7.
Sci Rep ; 13(1): 758, 2023 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-36641484

RESUMEN

Twelve healthy eight-week-old male Wistar rats weighing 200 g were used. Rats were chosen randomly, and their tails were identified and separated into cages/groups. The first group received an oral dose of 11.5 mg of levetiracetam in 5 mL of water, and the second group was given date syrup (250 g mixed with 250 mL water) for seven days, then 11.5 mg LEV in 5 mL water on day 7. One week of preadministered date molasses significantly decreased levetiracetam pharmacokinetic parameters in rats, such as Cmax (72 vs. 14 ng/mL, p = 0.01), Tmax (1.78 vs. 0.44 h, p < 0.001), and AUC (880 vs. 258 ng.h/mL, p < 0.001). This decrease in plasma levetiracetam levels caused by date molasses could be attributed to decreased levetiracetam absorption. On the other hand, the current study discovered that rats given date molasses for a week had a reduced rate and extent of absorption. As a result, date molasses might increase the risk of epileptic seizures in oral LEV-treated ones.


Asunto(s)
Anticonvulsivantes , Piracetam , Ratas , Masculino , Animales , Levetiracetam , Melaza , Ratas Wistar
8.
J Popul Ther Clin Pharmacol ; 29(4): e202-e210, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36579951

RESUMEN

Anti-diabetic therapies possess many side effects; thus, searching for alternative strategies with low cost, minimal side effects, and high therapeutic value is very important. The present study aimed to explore the combined use of selenium yeast (SY) and standard anti-diabetic drug pioglitazone (PGZ) for diabetes mellitus (DM) treatment in streptozotocin (STZ)-induced DM. STZ was injected daily intraperitoneally with a low dose (40 mg/kg) into Sprague-Dawley rats to induce DM. The synergistic effect of the SY (0.2 mg/kg) and PGZ (0.65 mg/kg) on DM complications was evaluated after 88 weeks of treatment. The impact of our medication on glucose levels, insulin sensitivity, lipid abnormalities, oxidative mediators, and inflammatory markers was assessed by biochemical techniques. STZ-induced diabetes has toxic effects, including toxic hepatic tissues, lipid disturbances, massive oxidative damage, and hyperinflammation. Experimental rats either treated with monotherapy alone or combined therapy resulted in a significant anti-diabetic effect. The PGZ+ SY combination has the best effect, as illustrated by significant (P < 0.05) decreases in fasting blood glucose, (FBG) insulin, HbA1c, and HOMA-IR levels. This combination attenuated (P < 0.05) lipid disturbances and their associated elevated atherogenicity biomarkers. At the same time, treatments with PGZ+ SY exhibited an anti-inflammatory effect as they ameliorated the increase in inflammatory parameters (CRP, TNF-α, IL-6). Also, it restored the total antioxidant capacity and peroxisome proliferator-activated receptor (PPARƔ) levels that were decreased by STZ-DM induction. In conclusion, this study finds PGZ+ SY as a promising DM therapeutic alternative. This synergistic combination alleviates most DM-related complications and insulin resistance.


Asunto(s)
Diabetes Mellitus Experimental , Resistencia a la Insulina , Selenio , Ratas , Humanos , Animales , Pioglitazona/uso terapéutico , Selenio/uso terapéutico , Saccharomyces cerevisiae , Estreptozocina/uso terapéutico , Ratas Sprague-Dawley , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/complicaciones , Lípidos/uso terapéutico , Hipoglucemiantes/farmacología , Glucemia
9.
Heliyon ; 8(10): e11015, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36281394

RESUMEN

Esomeprazole is used in various clinical settings where a decrease in gastric acid production is desired since it is a proton pump inhibitor. Apixaban, an anticoagulant, is used to reduce the risk of stroke in patients with certain cardiovascular diseases. This research aims to examine the effects of giving esomeprazole and apixaban to rats simultaneously, as well as to measure their pharmacokinetics and look for statistical differences or interactions. A method for the simultaneous determination of esomeprazole and apixaban in rat plasma was developed using HPLC/MS and validated by ICH guidelines. Five groups of Wistar rats were created, and the drugs were administered as follows: esomeprazole (5 mg/kg) intravenously, apixaban (125 mcg/Kg) intravenously, esomeprazole (5 mg/kg) orally, apixaban (250 mcg/kg) orally, and esomeprazole (5 mg/kg) and apixaban (250 mcg/kg) both orally. Both drugs' concentrations were measured in plasma samples collected on a predetermined schedule. The pharmacokinetics of both drugs were calculated and statistically analyzed using a 90% confidence interval and non-compartmental analysis. When the two drugs were combined, apixaban's Cmax and AUC increased while esomeprazole's Cmax and AUC decreased. On the other hand, Apixaban's Tmax decreased with an increase in esomeprazole's Tmax, indicating a possible interaction between the two drugs. When both drugs were taken together, their bioavailability was reduced, implying that less esomeprazole was absorbed over time.

10.
Drug Dev Ind Pharm ; 48(1): 12-20, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35695255

RESUMEN

OBJECTIVE: This study reports new solubility and physicochemical data for ribociclib (RCB) in water and ten organic solvents including "methanol (MeOH), ethanol (EtOH), isopropyl alcohol (IPA), n-butanol (n-BuOH), propylene glycol (PG), polyethylene glycol-400 (PEG-400), acetone, ethyl acetate (EA), Transcutol-HP (THP), and dimethyl sulfoxide (DMSO)" at 293.2-313.2 K and 101.1 kPa. SIGNIFICANCE: The obtained data are useful for the industrial applications of RCB. METHODS: The solubility of RCB was measured and regressed using "van't Hoff, Buchowski-Ksiazczak λh, the modified Apelblat, and Jouyban models." RESULTS: The overall deviations of <4.0% were recorded for all four models. The maximum mole fraction solubility of RCB was 2.66 × 10-2 in PEG-400 at 313.2 K, however, the lowest one was in the water. The RCB solubility increased with temperature and the order followed in the water and ten different organic solvents was PEG-400 (2.66 × 10-2) > THP (1.00 × 10-2) > PG (5.39 × 10-3) > DMSO (5.00 × 10-3) > n-BuOH (3.23 × 10-3) > acetone (3.11 × 10-3) > IPA (1.58 × 10-3) > EA (1.41 × 10-3) > EtOH (1.37 × 10-3) > MeOH (8.10 × 10-4) > water (2.38 × 10-5) at 313.2 K. The maximum solute-solvent interactions were found in RCB-PEG-400 in comparison with other combination of RCB and solvents. "Apparent thermodynamic analysis" indicated an "endothermic and entropy-driven dissolution" of RCB in water and ten organic solvents. CONCLUSIONS: Based on all these data and observations, PEG-400 can be used as the best co-solvent for RCB solubilization.


Asunto(s)
Antineoplásicos , Agua , 2-Propanol , Acetona , Aminopiridinas , Dimetilsulfóxido , Metanol , Purinas , Solubilidad , Solventes , Temperatura , Termodinámica
12.
Pharmaceuticals (Basel) ; 15(2)2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35215305

RESUMEN

The current study is a randomized, open-label, two-period, two-sequence, two-way crossover pharmacokinetic study in healthy Jordanian subjects to evaluate the pharmacokinetics and bioequivalence profile of two cases of empagliflozin 10 mg under fasting and fed conditions. The plasma concentrations of empagliflozin were determined using an HPLC-MS/MS method. Tolerability and safety were assessed throughout the study. This study included 26 subjects, 26 in both fasting and fed groups.The pharmacokinetic parameters, which included the area under the concentration-time curve from time zero to infinity (AUC0-inf) and the final quantifiable concentration (AUC0-last), maximum serum concentration (Cmax), and time to reach the maximum drug concentration (Tmax) were found to be within an equivalence margin of 80.00-125.00%. The pharmacokinetic profiles show that the empagliflozin test and parent reference cases were bioequivalent in healthy subjects. The two treatments' safety evaluations were also comparable.

14.
Molecules ; 26(13)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206357

RESUMEN

In the current work, a simple, economical, accurate, and precise HPLC method with UV detection was developed to quantify Favipiravir (FVIR) in spiked human plasma using acyclovir (ACVR) as an internal standard in the COVID-19 pandemic time. Both FVIR and ACVR were well separated and resolved on the C18 column using the mobile phase blend of methanol:acetonitrile:20 mM phosphate buffer (pH 3.1) in an isocratic mode flow rate of 1 mL/min with a proportion of 30:10:60 %, v/v/v. The detector wavelength was set at 242 nm. Maximum recovery of FVIR and ACVR from plasma was obtained with dichloromethane (DCM) as extracting solvent. The calibration curve was found to be linear in the range of 3.1-60.0 µg/mL with regression coefficient (r2) = 0.9976. However, with acceptable r2, the calibration data's heteroscedasticity was observed, which was further reduced using weighted linear regression with weighting factor 1/x. Finally, the method was validated concerning sensitivity, accuracy (Inter and Intraday's % RE and RSD were 0.28, 0.65 and 1.00, 0.12 respectively), precision, recovery (89.99%, 89.09%, and 90.81% for LQC, MQC, and HQC, respectively), stability (% RSD for 30-day were 3.04 and 1.71 for LQC and HQC, respectively at -20 °C), and carry-over US-FDA guidance for Bioanalytical Method Validation for researchers in the COVID-19 pandemic crisis. Furthermore, there was no significant difference for selectivity when evaluated at LLOQ concentration of 3 µg/mL of FVIR and relative to the blank.


Asunto(s)
Amidas/análisis , Amidas/sangre , Antivirales/análisis , Antivirales/sangre , Bioensayo/métodos , Tratamiento Farmacológico de COVID-19 , Cromatografía Líquida de Alta Presión/métodos , Extracción Líquido-Líquido/métodos , Pirazinas/análisis , Pirazinas/sangre , Aciclovir/análisis , Aciclovir/sangre , COVID-19/sangre , Calibración , Estabilidad de Medicamentos , Congelación , Humanos , Estándares de Referencia , Reproducibilidad de los Resultados , Solventes/química
15.
Sci Total Environ ; 761: 143229, 2021 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-33160673

RESUMEN

Industrial processes generate toxic organic molecules that pollute environment water. Phenol and its derivative are classified among the major pollutant compounds found in water. They are naturally found in some industrial wastewater effluents. The removal of phenol compounds is therefore essential because they are responsible for severe organ damage if they exist above certain limits. In this study, ground Ziziphus leaves were utilized as adsorbents for phenolic compounds from synthetic wastewater samples. Several experiments were performed to study the effect of several conditions on the capacity of the Ziziphus leaves adsorbent, namely: the initial phenol concentration, the adsorbent concentration, temperature, pH value, and the presence of foreign salts (NaCl and KCl). The experimental results indicated that the adsorption process reached equilibrium in about 4 h. A drop in the amount of phenol removal, especially at higher initial concentration, was noticed upon increasing the temperature from 25 to 45 °C. This reflects the exothermic nature of the adsorption process. This was also confirmed by the calculated negative enthalpy of adsorption (-64.8 kJ/mol). A pH of 6 was found to be the optimum value at which the highest phenol removal occurred with around 15 mg/g at 25 °C for an initial concentration of 200 ppm. The presence of foreign salts has negatively affected the phenol adsorption process. The fitting of the experimental data, using different adsorption isotherms, indicated that the Harkins-Jura isotherm model was the best fit, evident by the high square of the correlation coefficient (R2) values greater than 0.96. The kinetic study revealed that the adsorption was represented by a pseudo-second-order reaction. The results of this study offer a basis to use Ziziphus leaves as promising adsorbents for efficient phenol removal from wastewater.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Ziziphus , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Fenol , Fenoles , Hojas de la Planta/química , Agua , Contaminantes Químicos del Agua/análisis
16.
Sci Total Environ ; 688: 1327-1334, 2019 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-31726562

RESUMEN

Olive mills wastewater (OMW) causes a serious environmental problem in the olive oil producing countries. This is due to its high organic matter content (COD), acidic pH values, suspended solids and high content of phytotoxic and antibacterial phenolic compounds. In this study, titanium dioxide (TiO2) as an adsorbent to reduce the COD value of the olive mill wastewater was investigated. Several variables were studied including the removal efficiency, effect of the initial COD value, amount of TiO2, temperature and pH value. The results revealed that the adsorption reached equilibrium within <120 min. Isotherm studies showed that the adsorption equilibrium data is in agreement with Freundlich isotherm. In addition, the results showed that the adsorption process was spontaneous and exothermic. The kinetic study indicated that adsorption did follow a pseudo-second order reaction. Variation of the amount of the TiO2 showed that using of 1.5 and 2 g/L of TiO2 caused the COD to drop from 1000 ppm to about 100 ppm (equilibrium concentration) in about 120 min. However, the use of 1 g/L of TiO2 exhibited almost the same effect on the COD-uptake, and the equilibrium concentration was about 400 ppm. The COD uptake was found to be inversely proportional with the temperature, pH value and the addition of salts such as sodium chloride (NaCl) and potassium chloride (KCl).

17.
Bioorg Med Chem ; 25(15): 3911-3921, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28583806

RESUMEN

(1S,2E,4S,6R,7E,11E)-2,7,11-cembratriene-4,6-diol (1) and its 4-epi-analog (2) are diterpene precursors of the key flavor components in most Nicotiana (tobacco) species that purposely degraded during commercial tobacco fermentation. Angiogenesis, recruitment of new blood vessels, is important for tumor growth, survival and metastasis that can be targeted to control cancer. This study shows evidences and potential of the cembranoid 1 as a potent angiogenesis modulator through targeting VEGFR2. In silico study suggested favorable docking scores and binding affinity of 1 at the ATP binding pocket of VEGFR2. The binding mode of 1 was parallel to the standard FDA-approved antiangiogenic drug sunitinib (4). In vitro, cembranoid 1 significantly reduced the activated VEGFR2 levels in multiple breast cancer cell lines. Intraperitoneal 40mg/kg, 3X/week treatment of 1 significantly reduced the MDA-MB-231 cells breast tumor size in mice. Immunohistochemistry and Western blotting analysis of the treated mice tumors showed significant downregulation of the vasculogenesis marker CD31 and suppressed activated VEGFR2-paxillin-FAK pathway. Matrigel study in Swiss albino mice showed similar trend. The tobacco cembranoid 1 is a potential antiangiogenic lead useful for future use to control breast malignancies.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Diterpenos/farmacología , Nicotiana/química , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Bioorg Med Chem ; 24(22): 5748-5761, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27681240

RESUMEN

(1S,2E,4S,6R,7E,11E)-2,7,11-Cembratriene-4,6-diol (1) and its 4-epi-analog (2) are the cembranoid precursors to several key flavor ingredients in most Nicotiana (tobacco) species. Nearly 40-60% of 1 and 2 are purposely degraded during the commercial tobacco fermentation. However, 1 and 2 display promising bioactivities, including anticancer. Breast cancer is the most diagnosed cancer in women and ranked second female disease killer. The receptor tyrosine kinase c-Met correlates with aggressiveness of certain breast cancer phenotypes and thus considered a valid therapeutic target. This study reports the discovery and optimization of the tobacco-based cembranoid 1 as a novel c-Met inhibitory scaffold using combined structure- and ligand-based approaches. 1 displayed antiproliferative, anti-migratory and anti-invasive effects against the c-Met overexpressing MDA-MB-231 breast cancer cells at moderate µM concentrations. The Z'-LYTE kinase platform and Western blot analysis identified c-Met as a potential macromolecular target. Rationally designed carbamate analogs were proposed to probe additional targeted c-Met interactions and improve the cellular potency. The 6-phenyl carbamate 3 showed enhanced c-Met inhibitory activity. Structure-activity relationships of different substituents on the 3's phenyl moiety were studied. The most active analog 20 showed potent in vitro anticancer activity against the MDA-MB-231 breast cancer cells at low µM concentrations, with minimal toxicity on the non-tumorigenic MCF-10A mammary epithelial cells. Cembranoid 20 potently inhibited the c-Met catalytic activity in Z'-LYTE kinase assay and various cellular c-Met-driven signaling pathways. Furthermore, 20 displayed a robust antitumor activity in a breast cancer xenograft athymic mouse model and thus promoted to the lead rank. Cembranoids are novel c-Met inhibitors appropriate for future use to control c-Met dependent malignancies.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Diterpenos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Diterpenos/síntesis química , Diterpenos/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas c-met/metabolismo , Relación Estructura-Actividad
19.
Biosens Bioelectron ; 77: 491-8, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26457734

RESUMEN

Currently used cancer marker for prostate adenocarcinoma (PC), serum prostate-specific antigen (PSA), greatly overestimates PC population. Patients with high PSA levels have to undergo unnecessary but physically painful and expensive procedure such as prostate biopsies repeatedly. The reliability of PC test can be greatly increased by finding a protein that is secreted selectively by malignant, but not normal, prostate cells. A recently discovered novel protein, referred as neuroendocrine marker (NEM), is secreted only by malignant prostate cells and released in blood circulation. Although NEM seems to be significantly more reliable based on the data obtained from a limited cohort, currently available NEM ELISA is not suitable for undertaking a large study. Therefore, the goal of the present study was to develop an alternative, label-free assay system that can reliably measure NEM and PSA in patient samples. Herein an optofluidic chip that can reliably detect PSA as well as NEM in patient samples has been developed. The optofluidic chip, which consists of arrayed nanopore-based sensors fabricated from anodic aluminum oxide (AAO) thin film, offers improved sensitivity upon the optimization of the concentration of the detector antibodies immobilized on the sensor surface. The results demonstrate that the chip is reliable, extremely sensitive and requires just 1 µl of patient serum (or even less) to measure PSA and NEM even in a non-cancer individual. Compared with the traditional ELISA for PSA, the nanopore-based sensor assay is 50-100 fold more sensitive, and offers many advantages such as elimination of labeled antigen, need for sophisticated equipment and highly trained individuals. These advantages, along with the low cost, should make the technology suitable for point-of-care application to screen elderly male populations for PC and to monitor the progress of patients undergoing PC treatment.


Asunto(s)
Biomarcadores de Tumor/sangre , Inmunoensayo/instrumentación , Dispositivos Laboratorio en un Chip , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Resonancia por Plasmón de Superficie/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Masculino , Membranas Artificiales , Nanoporos/ultraestructura , Dispositivos Ópticos , Neoplasias de la Próstata/diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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