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1.
AAPS PharmSciTech ; 22(5): 161, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34031791

RESUMEN

Atorvastatin (ATV) is a poorly water-soluble drug that exhibits poor oral bioavailability. Therefore, present research was designed to develop ATV solid dispersions (SDs) to enhance the solubility, drug release, and oral bioavailability. Various SDs of ATV were formulated by conventional and microwave-induced melting methods using Gelucire®48/16 as a carrier. The formulated SDs were characterized for different physicochemical characterizations, drug release, and oral bioavailability studies. The results obtained from the different physicochemical characterization indicate the molecular dispersion of ATV within various SDs. The drug polymer interaction results showed no interaction between ATV and used carrier. There was marked enhancement in the solubility (1.95-9.32 folds) was observed for ATV in prepared SDs as compare to pure ATV. The drug content was found to be in the range of 96.19% ± 2.14% to 98.34% ± 1.32%. The drug release results revealed significant enhancement in ATV release from prepared SDs compared to the pure drug and the marketed tablets. The formulation F8 showed high dissolution performance (% DE30 value of 80.65 ± 3.05) among the other formulations. Optimized Gelucire®48/16-based SDs formulation suggested improved oral absorption of atorvastatin as evidenced with improved pharmacokinetic parameters (Cmax 2864.33 ± 573.86 ng/ml; AUC0-t 5594.95 ± 623.3 ng/h ml) as compared to ATV suspension (Cmax 317.82 ± 63.56 ng/ml; AUC0-t 573.94 ± 398.9 ng/h ml) and marketed tablets (Cmax 852.72 ± 42.63 ng/ml; 4837.4 ± 174.7 ng/h ml). Conclusively, solid dispersion-based oral formulation of atorvastatin could be a promising approach for enhanced drug solubilization, dissolution, and subsequently improved absorption.


Asunto(s)
Atorvastatina/farmacocinética , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacocinética , Administración Oral , Animales , Atorvastatina/sangre , Atorvastatina/química , Disponibilidad Biológica , Portadores de Fármacos/química , Liberación de Fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/sangre , Inhibidores de Hidroximetilglutaril-CoA Reductasas/química , Técnicas In Vitro , Ratas , Solubilidad , Comprimidos
2.
Drug Dev Ind Pharm ; 45(10): 1610-1616, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31311329

RESUMEN

Mefenamic acid (MA) has been reported as a weakly soluble drug which presents weak in vivo absorption upon oral administration using conventional formulations. Solid dispersions (SDs) have been investigated extensively in literature for enhancing the solubility and bioavailability of weakly-soluble molecules. Hence, the aim of proposed study was to prepare MA novel formulations in the form of SDs using hot-melt extrusion technology in order to enhance its palatability, bioavailability, and pharmacodynamics effects/anti-inflammatory efficacy. Various SDs of MA were prepared using hot-melt extrusion technology, characterized physically and investigated for dissolution tests. Optimized SD formulations of MA were being subjected to palatability, pharmacodynamics, and pharmacokinetic studies in rats. Optimized SD of MA showed significant rat palatability tastes as compared with pure and marketed MA (p < .05). Anti-inflammatory efficacy of 20% SD and 25% SD of MA was found to be 86.44 and 89.83%, respectively, in comparison with 74.57 and 78.24% by pure MA and marketed MA, respectively. The anti-inflammatory efficacy of optimized SD was found to be significant as compared with pure and marketed MA (p < .05). The oral absorption of MA from optimized 20% SD was also noted as statistically significant as compared with pure MA (p < .05). The relative bioavailability of MA from 20 and 25% SDs was 2.97 and 2.24-folds higher than pure MA. The results of this study suggested that SDs prepared using hot-melt extrusion technology are capable to enhance palatability, anti-inflammatory efficacy, and oral bioavailability of MA in comparison with pure drug.


Asunto(s)
Ácido Mefenámico/química , Ácido Mefenámico/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/metabolismo , Antiinflamatorios/farmacología , Disponibilidad Biológica , Rastreo Diferencial de Calorimetría/métodos , Química Farmacéutica/métodos , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Femenino , Tecnología de Extrusión de Fusión en Caliente/métodos , Inflamación/tratamiento farmacológico , Ácido Mefenámico/metabolismo , Ratas , Ratas Wistar , Solubilidad/efectos de los fármacos
3.
Pharm Dev Technol ; 24(6): 711-719, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30714850

RESUMEN

Orally dissolving tablets (ODTs) represent one of the recent advances in drug delivery. The foremost objective of this study was to optimize the utilization of lubricant sodium stearyl fumarate in the preparation of dextromethorphan hydrobromide ODTs with enhanced taste-masking properties. The simple blending of sodium stearyl fumarate with the powder bed would result in taste-masking through physical adsorption of the lubricant particles on the drug particles. A randomized 32 full factorial experimental design was used to characterize the relationship between lubricant ratio (X1), mixing time (X2), and the tablet properties. The tablets were assessed for friability, hardness, disintegration time, and in-vitro dissolution. All tablets showed hardness within the range of 3.0-3.7 kp, and the % loss in friability test was less than 1.1%. The in-vitro disintegration time ranged between 9 and 25 s. An in-vitro drug release study of the prepared ODTs showed that more than 90% of the drug was released within 30 min. A palatability test of the optimized formula conducted in human volunteers showed acceptable taste and mouthfeel with in-vivo disintegration time of 17 s. Thus, results obtained convincingly showed successful fast disintegration of the prepared tablets and acceptable palatability when using sodium stearyl fumarate as a taste masking agent.


Asunto(s)
Antitusígenos/química , Dextrometorfano/química , Excipientes/química , Fumaratos/química , Administración Oral , Antitusígenos/administración & dosificación , Dextrometorfano/administración & dosificación , Composición de Medicamentos , Dureza , Solubilidad , Comprimidos , Gusto/efectos de los fármacos
4.
Saudi Pharm J ; 27(5): 629-636, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31297016

RESUMEN

This study was conducted to formulate, characterize, and investigate the bioavailability of hydrocortisone (HCT) when prepared as solid dispersions. HCT was mixed in an organic solvent with polyethylene glycol 4000 (PEG 4000) and Kolliphor® P 407. Spray drying technique was employed to form a solid dispersion formulation at a specific ratio. Physical and chemical characterization of the formed particles were achieved using differential scanning calorimetry, scanning electron microscopy, Fourier transform infrared spectroscopy, and powder X-ray diffractometry. Furthermore, comparative in vitro and in vivo studies were conducted between the formulated particles against neat HCT. The formulated solid dispersion showed elongated particles with leaf-like structure. Formation of new chemical bonds in the formed particle was suggested due to the change in the vibrational wave numbers and the significant improvement in the bioavailability of the dispersed particles proved the importance of this technique.

5.
Saudi Pharm J ; 27(2): 264-273, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30766439

RESUMEN

Apigenin (APG) is a poorly soluble bioactive compound/nutraceutical which shows poor bioavailability upon oral administration. Hence, the objective of this research work was to develop APG solid dispersions (SDs) using different techniques with the expectation to obtain improvement in its in vitro dissolution rate and in vivo bioavailability upon oral administration. Different SDs of APG were prepared by microwave, melted and kneaded technology using pluronic-F127 (PL) as a carrier. Prepared SDs were characterized using "thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infra-red (FTIR) spectrometer, powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM)". After characterization, prepared SDs of APG were studied for in vitro drug release/dissolution profile and in vivo pharmacokinetic studies. The results of TGA, DSC, FTIR, PXRD and SEM indicated successful formation of APG SDs. In vitro dissolution experiments suggested significant release of APG from all SDs (67.39-84.13%) in comparison with control (32.74%). Optimized SD of APG from each technology was subjected to in vivo pharmacokinetic study in rats. The results indicated significant improvement in oral absorption of APG from SD prepared using microwave and melted technology in comparison with pure drug and commercial capsule. The enhancement in oral bioavailability of APG from microwave SD (319.19%) was 3.19 fold as compared with marketed capsule (100.00%). Significant enhancement in the dissolution rate and oral absorption of APG from SD suggested that developed SD systems can be successfully used for oral drug delivery system of APG.

6.
Saudi Pharm J ; 26(5): 733-738, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29991918

RESUMEN

This study assessed the wound healing potential and antimicrobial activity of henna, pomegranate and myrrh extract formulations and their blend in excision, and dead space wound models in rats in comparison to a marketed ointment (gentamycin). The natural extracts were used in ointment formulations alone or in a combination of three extracts at a total concentration of 15% w/w in medications. The percent of wound contraction in case of henna, myrrh, pomegranate, the blend and gentamycin (10 mg/kg) were 85.90-98.5%, 88.35-99.52%, 93.55-100%, 97.30-100%, and 90.25-100% from days 16 to 20, respectively. The blended formulation showed the highest increase in the percent of wound contraction and decrease in the epithelisation period compared to other formulations and showed comparable results to the standard ointment. The histological studies of excision biopsy at day 24 showed healed skin structures with normal epithelisation, the restoration of adnexa and fibrosis within the dermis in all of the formulation- and gentamycin-treated groups while the control group lagged behind in the formation of the amount of ground substance in the granulation tissue. The formulations showed antimicrobial activity against Candida, Staphylococcus aureus, mucous membrane infections and E. coli topical infections. The study proved the wound healing potential and antimicrobial activity of the herbal extract.

7.
Pharm Dev Technol ; 22(7): 928-938, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27469993

RESUMEN

CONTEXT: Multiple response optimization is an efficient technique to develop sustained release formulation while decreasing the number of experiments based on trial and error approach. OBJECTIVE: Diclofenac matrix tablets were optimized to achieve a release profile conforming to USP monograph, matching Voltaren®SR and withstand formulation variables. The percent of drug released at predetermined multiple time points were the response variables in the design. Statistical models were obtained with relative contour diagrams being overlaid to predict process and formulation parameters expected to produce the target release profile. MATERIALS AND METHODS: Tablets were prepared by wet granulation using mixture of equivalent quantities of Eudragit RL/RS at overall polymer concentration of 10-30%w/w and compressed at 5-15KN. RESULTS AND DISCUSSION: Drug release from the optimized formulation E4 (15%w/w, 15KN) was similar to Voltaren, conformed to USP monograph and found to be stable. Substituting lactose with mannitol, reversing the ratio between lactose and microcrystalline cellulose or increasing drug load showed no significant difference in drug release. Using dextromethorphan hydrobromide as a model soluble drug showed burst release due to higher solubility and formation of micro cavities. CONCLUSION: A numerical optimization technique was employed to develop a stable consistent promising formulation for sustained delivery of diclofenac.


Asunto(s)
Diclofenaco , Composición de Medicamentos , Polímeros , Química Farmacéutica , Preparaciones de Acción Retardada , Comprimidos
9.
Saudi Pharm J ; 25(5): 688-695, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28725140

RESUMEN

The rapid availability of the drug at the site of action followed by maintaining its effect for a long period of time is of great clinical importance. Thus, the purpose of the present study was to prepare and evaluate multi-layered matrix tablets of diclofenac using Eudragit RL/RS blend to achieve both immediate and sustained therapeutic effects. Diclofenac potassium (25 mg) was incorporated in an outer immediate release layer to provide immediate pain relief whereas diclofenac sodium (75 mg) was incorporated in the inner core to provide extended drug release. Wet granulation was employed to prepare the inner core of the tablets that were further layered with an immediate release drug layer in the perforated pan coater. The in-vitro and in-vivo performance of the developed formulation was compared with the marketed products Voltaren® SR 75 mg and Cataflam® 25 mg. The in-vitro drug release of the prepared formulation showed similarity (f2 = 66.19) to the marketed product. The pharmacokinetic study showed no significant difference (p > 0.05) in AUC0-24 and Cmax between the test and reference formulations. The AUC0-24 values were 105.36 ± 83.3 and 92.87 ± 55.53 µg h/ml whereas the Cmax values were 11.25 ± 6.87 and 12.97 ± 8.45 µg/ml, for the test and reference, respectively. The multi-layered tablets were proved to be bioequivalent with the commercially available tablets and were in agreement with the observed in-vitro drug release results. Stable physical characteristics and drug release profiles were observed in both long term and accelerated conditions stability studies.

10.
Acta Pol Pharm ; 73(2): 439-52, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27180437

RESUMEN

Hydrophilic matrices, especially HPMC based, are widely used to provide sustained delivery where drug release occurs mainly by diffusion. A 3(2) full factorial design was used to develop and evaluate HPMC matrix tablet for sustained delivery of diclofenac. The influences of polymer concentration/viscosity, diluent type/ratio, drug load/solubility, compression force and pH change on drug release were investigated. Ten tablet formulations were prepared using wet granulation. HPMC K15M (10-30% w/w) was used as the polymer forming matrix. The release kinetics, compatibility studies, lot reproducibility and effect on storage were discussed. Increasing polymer concentration and compression force showed antagonistic effect on release rate. Mannitol tends to increase release rate more than lactose. Reversing diluent ratio between lactose and MCC did not affect drug release. Changing pH resulted in burst release whereas drug solubility is pH independent. F1 showed similar release to Voltaren SR and followed Higuchi model. Drug and polymer were compatible to each other. The formulation is stable at long and intermediate conditions with a significant increase in release rate at accelerated conditions due to water uptake and polymer swelling. The developed formulation was successful for a sustained delivery of diclofenac.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Diclofenaco/química , Portadores de Fármacos , Derivados de la Hipromelosa/química , Rastreo Diferencial de Calorimetría , Química Farmacéutica , Cristalografía por Rayos X , Preparaciones de Acción Retardada , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Cinética , Modelos Químicos , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Comprimidos , Tecnología Farmacéutica/métodos , Viscosidad
11.
Materials (Basel) ; 16(15)2023 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-37570067

RESUMEN

Lung cancer is a formidable challenge in clinical practice owing to its metastatic nature and resistance to conventional treatments. The codelivery of anticancer agents offers a potential solution to overcome resistance and minimize systemic toxicity. The encapsulation of these agents within nanostructured lipid carriers (NLCs) provides a promising strategy to enhance lymphatic delivery and reduce the risk of relapse. This study aimed to develop an NLC formulation loaded with Gefitinib and Azacitidine (GEF-AZT-NLC) for the treatment of metastatic-resistant lung cancer. The physicochemical properties of the formulations were characterized, and in vitro drug release was evaluated using the dialysis bag method. The cytotoxic activity of the GEF-AZT-NLC formulations was assessed on a lung cancer cell line, and hemocompatibility was evaluated using suspended red blood cells. The prepared formulations exhibited nanoscale size (235-272 nm) and negative zeta potential values (-15 to -31 mV). In vitro study revealed that the GEF-AZT-NLC formulation retained more than 20% and 60% of GEF and AZT, respectively, at the end of the experiment. Hemocompatibility study demonstrated the safety of the formulation for therapeutic use, while cytotoxicity studies suggested that the encapsulation of both anticancer agents within NLCs could be advantageous in treating resistant cancer cells. In conclusion, the GEF-AZT-NLC formulation developed in this study holds promise as a potential therapeutic tool for treating metastatic-resistant lung cancer.

12.
Neurourol Urodyn ; 31(7): 1197-202, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22473872

RESUMEN

AIMS: To assess the effects of different doses and treatment durations of pregabalin and lamotrigine on the urodynamic parameters of an animal model of neurogenic detrusor overactivity (NDO). MATERIALS AND METHODS: Ninety rats were used; six as normal controls and the remaining 84 were divided as follows: Six "paraplegic controls," 6 "paraplegic-vehicle controls," and the remaining 72 divided into two equal groups. Group 1 was divided into six subgroups; pregabalin was given in doses of 10 mg/kg, 20 mg/kg, or 30 mg/kg for 1 or 2 weeks. Group 2 was similarly subdivided; lamotrigine was given in doses of 1.5 mg/kg, 3 mg/kg, or 6 mg/kg for 1 or 2 weeks. RESULTS: All paraplegic controls developed NDO within 3 weeks from spinalization. Their baseline bladder pressure (BBP) 19 ± 4.4 cmH(2) O, detrusor pressure at maximum capacity (DPMaxC) 47.6 ± 4.3 cmH(2) O, bladder capacity (BC) 0.45 ± 0.1 ml, and frequency of detrusor overactivity (FDO) 3.7 ± 0.9/min. Both pregabalin and lamotrigine produced significant improvement. Urodynamic values in those treated with 20 mg pregabalin for 1 or 2 weeks were: BBP 11.7 ± 1.3 and 9 ± 0.2 cmH(2) O, BC 0.6 ± 0.1 and 0.7 ± 0.01 ml, DPMaxC 17.3 ± 4.0 and 23 ± 2.6 cmH(2) O, FDO 2.1 ± 0.2/min and 1.7 ± 0.1/min. Urodynamic values in those treated with 3 mg/kg lamotrigine for 1 or 2 weeks were: BBP 9.7 ± 2.2 and 8.6 ± 1.9 cmH(2) O, DPMaxC 17.2 ± 1.8 and 29 ± 1.2 cmH(2) O, BC 0.7 ± 0.1 and 0.8 ± 0.1 ml, FDO 1.9 ± 0.2/min and 1.9 ± 0.2/min (P < 0.001). CONCLUSIONS: Pregabalin and lamotrigine may represent novel alternative treatments of NDO. Clinical trials remain to be performed.


Asunto(s)
Anticonvulsivantes/farmacología , Triazinas/farmacología , Vejiga Urinaria Neurogénica/tratamiento farmacológico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Vejiga Urinaria/efectos de los fármacos , Urodinámica/efectos de los fármacos , Ácido gamma-Aminobutírico/análogos & derivados , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Lamotrigina , Paraplejía/complicaciones , Pregabalina , Presión , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Vejiga Urinaria/inervación , Vejiga Urinaria/fisiopatología , Vejiga Urinaria Neurogénica/etiología , Vejiga Urinaria Neurogénica/fisiopatología , Vejiga Urinaria Hiperactiva/etiología , Vejiga Urinaria Hiperactiva/fisiopatología , Micción/efectos de los fármacos , Ácido gamma-Aminobutírico/farmacología
13.
Drug Dev Ind Pharm ; 38(8): 971-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22092113

RESUMEN

CONTEXT: Alternative strategies are being employed to develop liquid oral sustained release formulation. These included ion exchange resin, sustained release suspensions and in situ gelling systems. The later mainly utilizes alginate solutions that form gels upon contact with calcium which may be administered separately or included in the alginate solution as citrate complex. This complex liberates calcium in the stomach with subsequent gellation. The formed gel can break after gastric emptying leading to dose dumping. OBJECTIVE: Development of modified in situ gelling system which sustain dextromethorphan release in the stomach and intestine. METHODS: Solutions containing alginate with calcium chloride and sodium citrate were initially prepared to select the formulation sustaining the release in the stomach. The best formulation was combined with chitosan. All formulations were characterized with respect to flow, gelling capacity, gelling strength and drug release. RESULTS: Increasing the concentration of alginate increased the gelling capacity and strength and reduced the rate of drug release in gastric conditions with 2% w/v alginate being the best formulation. However, these formulations failed to sustain the release in the intestinal conditions. Incorporation of chitosan with alginate increased the gelling capacity and strength and reduced the rate of drug release compared to alginate only system. The effect was optimum in formulation containing 1.5% w/v chitosan. The sustained release pattern was maintained both in the gastric and intestinal conditions and was comparable to that obtained from the marketed product. CONCLUSION: Alginate-chitosan based in situ gelling system is promising for developing liquid oral sustained release.


Asunto(s)
Dextrometorfano/química , Geles/química , Soluciones Farmacéuticas/química , Administración Oral , Alginatos/química , Cloruro de Calcio/química , Química Farmacéutica/métodos , Quitosano/química , Citratos/química , Preparaciones de Acción Retardada , Dextrometorfano/administración & dosificación , Mucosa Gástrica/metabolismo , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Mucosa Intestinal/metabolismo , Soluciones Farmacéuticas/administración & dosificación , Citrato de Sodio , Viscosidad
14.
Pharmaceuticals (Basel) ; 15(9)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36145341

RESUMEN

Purpose: Ramipril (RMP)­an angiotensin-converting enzyme (ACE) inhibitor­and thymoquinone (THQ) suffer from poor oral bioavailability. Developing a combined liquid SNEDDS that comprises RMP and black seed oil (as a natural source of THQ) could lead to several formulations and therapeutic benefits. Methods: The present study involved comprehensive optimization of RMP/THQ liquid SNEDDS using self-emulsification assessment, equilibrium solubility studies, droplet size analysis, and experimentally designed phase diagrams. In addition, the optimized RMP/THQ SNEDDS was evaluated against pure RMP, pure THQ, and the combined pure RMP + RMP-free SNEDDS (capsule-in-capsule) dosage form via in vitro dissolution studies. Results: The phase diagram study revealed that black seed oil (BSO) showed enhanced self-emulsification efficiency with the cosolvent (Transcutol P) and hydrogenated castor oil. The phase diagram studies also revealed that the optimized formulation BSO/TCP/HCO-30 (32.25/27.75/40 % w/w) showed high apparent solubility of RMP (25.5 mg/g), good THQ content (2.7 mg/g), and nanometric (51 nm) droplet size. The in-vitro dissolution studies revealed that the optimized drug-loaded SNEDDS showed good release of RMP and THQ (up to 86% and 89%, respectively). Similarly, the isolation between RMP and SNEDDS (pure RMP + RMP-free SNEDDS) using capsule-in-capsule technology showed >84% RMP release and >82% THQ release. Conclusions: The combined pure RMP + RMP-free SNEDDS (containing black seed oil) could be a potential dosage form combining the solubilization benefits of SNEDDSs, enhancing the release of RMP/THQ along with enhancing RMP stability through its isolation from lipid-based excipients during storage.

15.
Saudi Med J ; 43(7): 678-686, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35830983

RESUMEN

OBJECTIVES: To detect the cotinine and nicotine serum concentrations of female and male C57BL/6J mice after a 4-week exposure to electronic (e)-cigarette vapors using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). METHODS: This experimental study was carried out at an animal facility and laboratories, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia, between January and August 2020. A 4-week exposure to e-cigarettes was carried out using male and female mice and serum samples were obtained for cotinine and nicotine quantification using UPLC-MS/MS. The chromatographic procedures involved the use of a BEH HSS T3 C18 column (100 mm x 2.1 mm, 1.7 µm) with acetonitrile as a mobile phase and 0.1% formic acid (2:98 v/v). RESULTS: The applied methodology has highly efficient properties of detection, estimation, and extraction, where the limit of quantification (LOQ) for nicotine was 0.57 ng/mL and limit of detection (LOD) for nicotine was 0.19 ng/mL, while the LOQ for cotinine was 1.11 ng/mL and LOD for cotinine was 0.38 ng/mL. The correlation coefficient was r2>0.99 for both compounds. The average recovery rate was 101.6±1.33 for nicotine and 100.4±0.54 for cotinine, while the precision and accuracy for cotinine and nicotine were less than 6.1. The serum cotinine level was higher in males (433.7±19.55) than females (362.3±16.27). CONCLUSION: This study showed that the gender factor might play a crucial role in nicotine metabolism.


Asunto(s)
Cigarrillo Electrónico a Vapor , Sistemas Electrónicos de Liberación de Nicotina , Animales , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Cotinina/química , Cotinina/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Nicotina , Espectrometría de Masas en Tándem/métodos
16.
J Urol ; 185(3): 981-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21247597

RESUMEN

PURPOSE: Few reports address the reoperation rate after sacral neuromodulation implants. We report our long-term results and reoperations during our 14-year experience with sacral neuromodulation at our center. MATERIALS AND METHODS: We retrospectively reviewed the patient database at our center to assess the long-term outcome, incidence and cause of surgical re-intervention after InterStim® sacral neuromodulation implantation for lower urinary tract dysfunction between 1994 and 2008. RESULTS: A total of 96 sacral neuromodulation devices were implanted in 88 women and 8 men. Indications for implantation were bladder pain syndrome in 47.9% of cases, urgency urinary incontinence in 35.4% and idiopathic urinary retention in 16.7%. The explantation rate was 20.8% and median time to removal was 18.5 months. Reasons for explantation in all subgroups were poor result in 12 patients, painful stimulation in 6 and radiation of stimulation to the leg in 2. Median long-term followup was 50.7 months. The long-term success rate was 87.5%, 84.8% and 73% in patients with idiopathic urinary retention, urgency urinary incontinence and bladder pain syndrome, respectively. Overall 39% of patients needed revision of the sacral neuromodulation implant. The main reason for revision was loss of stimulation in 58.5% of cases. The revision rate decreased with the introduction of the tined lead technique from 50% using lead Model 3092 to 31% using lead Model 3893 (Medtronic, Minneapolis, Minnesota). The battery was changed in 8 patients. Mean battery life was 101.8 months. CONCLUSIONS: Sacral neuromodulation is a minimally invasive procedure with a good long-term outcome. The reoperation rate has improved with advances in surgical technique and equipment.


Asunto(s)
Trastornos Urinarios/cirugía , Adulto , Femenino , Estudios de Seguimiento , Humanos , Neuroestimuladores Implantables , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
17.
PLoS One ; 16(4): e0249485, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33831070

RESUMEN

The aim of this work was to solubilize simvastatin (SIM) using different micellar solutions of various non-ionic surfactants such as Tween-80 (T80), Tween-20 (T20), Myrj-52 (M52), Myrj-59 (M59), Brij-35 (B35) and Brij-58 (B58). The solubility of SIM in water (H2O) and different micellar concentrations of T80, T20, M52, M59, B35 and B58 was determined at temperatures T = 300.2 K to 320.2 K under atmospheric pressure p = 0.1 MPa using saturation shake flask method. The experimental solubility data of SIM was regressed using van't Hoff and Apelblat models. The solubility of SIM (mole fraction) was recorded highest in M59 (1.54 x 10-2) followed by M52 (6.56 x 10-3), B58 (5.52 x 10-3), B35 (3.97 x 10-3), T80 (1.68 x 10-3), T20 (1.16 x 10-3) [the concentration of surfactants was 20 mM in H2O in all cases] and H2O (1.94 x 10-6) at T = 320.2 K. The same results were also recorded at each temperature and each micellar concentration of T80, T20, M52, M59, B35 and B58. "Apparent thermodynamic analysis" showed endothermic and entropy-driven dissolution/solubilization of SIM in H2O and various micellar solutions of T80, T20, M52, M59, B35 and B58.


Asunto(s)
Micelas , Modelos Moleculares , Simvastatina/química , Tensoactivos/química , Conformación Molecular , Polietilenglicoles/química , Solubilidad , Solventes/química , Termodinámica , Agua/química
18.
Bioengineered ; 12(1): 914-926, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33678142

RESUMEN

This study aimed to utilize cholesterol conjugation of 5-fluorouracil (5-FUC) and liposomal formulas to enhance the partitioning of 5-FU into low density lipoprotein (LDL) to target hepatocellular carcinoma (HCC). Thus, 5-FU and 5-FUCwere loaded into liposomes. Later, the direct loading and transfer of 5-FU, and 5-FUC from liposomes into LDL were attained. The preparations were characterized in terms of particle size, zeta potential, morphology, entrapment efficiency, and cytotoxicity using the HepG2 cell line. Moreover, the drug deposition into the LDL and liver tissues was investigated. The present results revealed that liposomal preparations have a nanosize range (155 - 194 nm), negative zeta potential (- 0.82 to - 16 mV), entrapment efficiency of 69% for 5-FU, and 66% for 5-FUC. Moreover, LDL particles have a nanosize range (28-49 nm), negative zeta potential (- 17 to -27 mV), and the entrapment efficiency is 11% for 5-FU and 85% for 5-FUC. Furthermore, 5-FUC loaded liposomes displayed a sustained release profile (57%) at 24 h compared to fast release (92%) of 5-FU loaded liposomes. 5-FUC and liposomal formulas enhanced the transfer of 5-FUC into LDL compared to 5-FU. 5-FUC loaded liposomes and LDL have greater cytotoxicity against HepG2 cell lines compared to 5-FU and 5-FUC solutions. Moreover, the deposition of 5-FUC in LDL (26.87ng/mg) and liver tissues (534 ng/gm tissue) was significantly increased 5-FUC liposomes compared to 5-FU (11.7 ng/g tissue) liposomal formulation. In conclusion, 5-FUC is a promising strategy for hepatic targeting of 5-FU through LDL-mediated gateway.


Asunto(s)
Supervivencia Celular/efectos de los fármacos , Fluorouracilo , Lipoproteínas LDL , Liposomas , Hígado/metabolismo , Animales , Carcinoma Hepatocelular/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Fluorouracilo/química , Fluorouracilo/metabolismo , Fluorouracilo/farmacología , Células Hep G2 , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Lipoproteínas LDL/química , Lipoproteínas LDL/metabolismo , Liposomas/química , Liposomas/metabolismo , Neoplasias Hepáticas/metabolismo , Masculino , Ratas , Ratas Wistar
19.
J Urol ; 184(5): 2023-8, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20850828

RESUMEN

PURPOSE: We evaluated the long-term results and durability of photoselective vaporization and holmium laser ablation as surgical treatment of small to medium prostates in a prospective, randomized study in men with obstructive benign prostatic hyperplasia. MATERIALS AND METHODS: From March 2005 to April 2007 we randomly allocated 109 patients with a prostate gland of less than 60 cc to prostate photoselective vaporization (52) or holmium laser ablation (57) and evaluated them 1, 2 and 3 years postoperatively. Functional followup included measurement of maximum urinary flow rate, post-void residual urine, International Prostate Symptom Score, quality of life, International Index of Erectile Function and prostate specific antigen. RESULTS: Mean ± SD preoperative prostate volume was 33.1 ± 14.5 and 37.3 ± 13.6 in the laser ablation and vaporization groups, respectively. All functional parameters improved significantly compared to baseline values in each group. There was no difference in International Prostate Symptom Score, quality of life, maximum urinary flow rate, post-void residual urine or percent of prostate specific antigen decrease between the 2 groups 1, 2 and 3 years postoperatively. At 3-year followup International Prostate Symptom Score had improved by 70.5%, quality of life had improved by 69.4%, maximum urinary flow rate had increased by 164% and post-void residual urine had decreased by 81% in the holmium laser ablation group. In the photoselective vaporization group International Prostate Symptom Score improved by 64.1%, quality of life improved by 65.5%, maximum urinary flow rate increased by 189% and post-void residual urine decreased by 79.5%. The overall re-treatment rate was 15.8% for holmium laser ablation vs 19.3% for photoselective vaporization. CONCLUSIONS: Prostate photoselective vaporization and holmium laser ablation are effective surgical treatments for benign prostatic hyperplasia. Postoperative functional improvements were significant and durable, and equivalent in the 2 groups. The 2 techniques have a similar complication rate.


Asunto(s)
Láseres de Estado Sólido/uso terapéutico , Prostatectomía/métodos , Hiperplasia Prostática/cirugía , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Prospectivos , Prostatectomía/efectos adversos , Hiperplasia Prostática/patología , Factores de Tiempo
20.
ACS Omega ; 5(12): 6461-6471, 2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32258881

RESUMEN

Luteolin (LT) is a poorly soluble bioactive compound that suffered bioavailability problems after oral administration. Hence, the aim of the proposed research work was to formulate and investigate various solid dispersions (SDs) of LT in order to enhance its dissolution and bioactivity. LT-SD was prepared using polyethylene glycol 4000 (PEG 4000) as a carrier at the mass ratios of 1:1, 1:2, and 1:4. LT-SD was prepared using different methods including fusion (FU), solvent evaporation (SE), and microwave irradiation (MI) methods. The prepared LT-SD was duly characterized in terms of differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) and evaluated for dissolution and in vitro antioxidant activity. The results of DSC, XRD, SEM, IR, and NMR suggested the formation of LT-SD. After 90 min of the dissolution study, the results displayed that the % release of LT from prepared SD was significantly higher compared with the pure LT and its physical mixture dispersion (PMD). LT-SD prepared using the MI method displayed the maximum release of LT (i.e., 97.78 ± 4.41%) at a 1:2 mass ratio of LT:PEG 4000. The LT-SD prepared using the SE method displayed the maximum release of 93.78 ± 3.98% at a mass ratio of 1:4 of LT:PEG 4000. The SD prepared by the MI method showed enhanced dissolution due to higher aqueous solubility and the reduction of particle size. The solid-state characterization studies (DSC, XRD, SEM, IR, and NMR studies) suggested the morphological conversion of LT into the amorphous form from the crystalline state. The results of the antioxidant study revealed that the formation LT-SD displayed significantly higher radical scavenging activity than the pure LT. Therefore, SD obtained using PEG 4000 could be a potential strategy for maximizing the solubility, in vitro dissolution, and therapeutic efficacy of LT.

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