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1.
J Sep Sci ; 46(6): e2200841, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36695632

RESUMEN

Taxol and 10-Deacetyl baccatin III are major taxanes in the bark, needles, and endophytes of Taxus baccata. The current study aimed to develop a process for their separation from different matrices. Crude taxoid was prepared by extraction of samples with methanol, followed by partitioning with dichloromethane and precipitation with hexane. Analytical high-performance liquid chromatography involved isocratic elution on C18 column (4.6 × 250 mm, 5 µm) with methanol-water (70:30 v/v) at a flow rate of 1 ml/min. Injection volume was 20 µl and detection was carried out at 227 nm. The content of Taxol and 10-Deacetyl baccatin III in bark, needles and endophytic culture broth was 11.19 and 1.75 µg/mg; 11.19 and 1.75 µg/mg; and 2.80 and 0.22 µg/L, respectively. Preparative high-performance liquid chromatography was done on C18 column (10 × 250 mm, 5 µm) at a flow rate of 10 ml/min. About 20 g crude taxoid was processed in < 3 h with a recovery of about 90% for both the analytes. The purity of recovered Taxol and 10-Deacetyl baccatin III determined by ultra-high-performance liquid chromatography-mass spectrometry was found to be 95.78 ± 3.63% and 99.72 ± 0.18%, respectively. The structure of recovered Taxol was confirmed by nuclear magnetic resonance. The method can find use in biotransformation studies.


Asunto(s)
Paclitaxel , Taxus , Paclitaxel/química , Cromatografía Líquida de Alta Presión , Endófitos/metabolismo , Agujas , Corteza de la Planta/química , Metanol/metabolismo , Taxoides/análisis , Espectrometría de Masas , Espectroscopía de Resonancia Magnética
2.
Pediatr Blood Cancer ; 69(5): e29625, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35253344

RESUMEN

INTRODUCTION: Retinoblastoma (RB) tumors having high-risk histopathologic features (HRFs) have an increased risk of metastasis and disease relapse. However, RB has not been studied widely in Pakistan. Therefore, we evaluated the association of clinical, histopathologic, and radiological findings with HRFs in patients with RB who were treated at the Indus Health & Hospital Network in Karachi, Pakistan. METHODS: We enrolled treatment-naïve patients with RB who received upfront enucleation from September 2017 to February 2021. We evaluated enucleated eyes with the Intraocular Classification of Retinoblastoma system and classified HRFs as invasion of the anterior chamber, including the iris and ciliary body, or massive invasion of the choroid, sclera, or optic nerve (postlaminar and/or up to the transection line). RESULTS: Of 117 patients with RB treated at our institution during the study period, 54 received upfront enucleation. Unilateral disease was present in 92.6% of cases. The most frequent disease signs and symptoms included the presence of vitreous seeds (30.6%) and leukocoria (100%), respectively. The most frequent HRFs and radiological findings comprised massive choroidal invasion (15.1%) and anterior chamber enhancement (66.7%), respectively. The majority (62.9%) of patients did not exhibit any HRFs. Female sex, pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma had significant predictive ability for HRF occurrence. CONCLUSION: Pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma are important clinical factors that should be taken into consideration before the management of RB. Early recognition of high-risk histopathological and radiological features is essential for appropriate treatment of RB.


Asunto(s)
Glaucoma , Hidroftalmía , Neoplasias de la Retina , Retinoblastoma , Enucleación del Ojo , Femenino , Humanos , Lactante , Invasividad Neoplásica , Neoplasias de la Retina/patología , Retinoblastoma/patología , Estudios Retrospectivos , Factores de Riesgo
3.
Nanotechnology ; 32(41)2021 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-34198267

RESUMEN

Polymer-lipid hybrid nanoparticles (PLHNPs) are novel nanoplatforms for the effective delivery of a lipophilic drug in the management of a variety of solid tumors. The present work was designed to develop exemestane (EXE) encapsulated D-alpha-tocopheryl polyethylene glycol succinate (TPGS) based PLHNPs (EXE-TPGS-PLHNPs) for controlled delivery of EXE for breast cancer management. EXE-TPGS-PLHNPs were formulated by single-step nano-precipitation technique and statistically optimized by a 33Box-Behnken design using Design expert®software. The polycaprolactone (PCL;X1), phospholipon 90 G (PL-90G;X2), and surfactant (X3) were selected as independent factors while particles size (PS;Y1), polydispersity index (PDI;Y2), and %entrapment efficiency (%EE;Y3) were chosen as dependent factors. The average PS, PDI, and %EE of the optimized EXE-TPGS-PLHNPs was observed to be 136.37 ± 3.27 nm, 0.110 ± 0.013, and 88.56 ± 2.15% respectively. The physical state of entrapped EXE was further validated by Fourier-transform infrared spectroscopy, differential scanning calorimetry, and powder x-ray diffraction that revealed complete encapsulation of EXE in the hybrid matrix of PLHNPs with no sign of significant interaction between drug and excipients.In vitrorelease study in simulated gastrointestinal fluids revealed initial fast release for 2 h after that controlled release profile up to 24 h of study. Moreover, optimized EXE-TPGS-PLHNPs exhibited excellent stability in gastrointestinal fluids as well as colloidal stability in different storage concentrations. Furthermore, EXE-TPGS-PLHNPs exhibited distinctively higher cellular uptake and time and dose-dependent cytotoxicity against MCF-7 breast tumor cells compared to EXE-PLHNPs without TPGS and free EXE. The obtained results suggested that EXE-TPGS-PLHNPs can be a promising platform for the controlled delivery of EXE for the effective treatment of breast cancer.


Asunto(s)
Androstadienos/farmacología , Antineoplásicos/farmacología , Portadores de Fármacos/síntesis química , Composición de Medicamentos/métodos , Liposomas/química , Nanopartículas/química , Androstadienos/metabolismo , Antineoplásicos/metabolismo , Materiales Biomiméticos/química , Supervivencia Celular/efectos de los fármacos , Liberación de Fármacos , Estabilidad de Medicamentos , Análisis Factorial , Colorantes Fluorescentes/química , Jugo Gástrico/química , Humanos , Cinética , Liposomas/ultraestructura , Células MCF-7 , Nanopartículas/ultraestructura , Fosfatidilcolinas/química , Poliésteres/química , Rodaminas/química , Vitamina E/química
4.
Pharm Biol ; 59(1): 941-952, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35294328

RESUMEN

CONTEXT: Traditionally, Inula racemosa Hook. f. (Asteraceae) has been reported to be effective in cancer treatment which motivated the authors to explore the plant for novel anticancer compounds. OBJECTIVE: To isolate and characterize new cytotoxic phytoconstituents from I. racemosa roots. MATERIALS AND METHODS: The column chromatography of I. racemosa ethyl acetate extract furnished a novel sesquiterpene lactone whose structure was established by NMR (1D/2D), ES-MS and its cytotoxic properties were assessed on HeLa, MDAMB-231, and A549 cell lines using MTT and LDH (lactate dehydrogenase) assays. Further, morphological changes were analyzed by flow cytometry, mitochondrial membrane potential, AO-EtBr dual staining, and comet assay. Molecular docking and simulation were performed using Glide and Desmond softwares, respectively, to validate the mechanism of action. RESULTS: The isolated compound was identified as racemolactone I (compound 1). Amongst the cell lines tested, considerable changes were observed in HeLa cells. Compound 1 (IC50 = 0.9 µg/mL) significantly decreased cell viability (82%) concomitantly with high LDH release (76%) at 15 µg/mL. Diverse morphological alterations along with significant increase (9.23%) in apoptotic cells and decrease in viable cells were observed. AO-EtBr dual staining also confirmed the presence of 20% apoptotic cells. A gradual decrease in mitochondrial membrane potential was observed. HeLa cells showed significantly increased comet tail length (48.4 µm), indicating broken DNA strands. In silico studies exhibited that compound 1 binds to the active site of Polo-like kinase-1 and forms a stable complex. CONCLUSIONS: Racemolactone I was identified as potential anticancer agent, which can further be confirmed by in vivo investigations.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Inula/química , Lactonas/farmacología , Sesquiterpenos/farmacología , Células A549 , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Lactonas/administración & dosificación , Lactonas/aislamiento & purificación , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Simulación del Acoplamiento Molecular , Raíces de Plantas , Sesquiterpenos/administración & dosificación , Sesquiterpenos/aislamiento & purificación
5.
Pharm Biol ; 58(1): 184-199, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32083987

RESUMEN

Context: Nephrotoxicity is a renal dysfunction that arises from direct exposure to environmental chemicals or as a side effect of therapeutic drugs. Boerhaavia diffusa Linn. (Nyctaginaceae), Rheum emodi Wall. Ex. Meissn. (Polygonaceae), Nelumbo nucifera Gaertn. (Nelumbonaceae) and Crataeva nurvala Buch-Ham. (Capparidaceae) are well-recognized medicinal plants of Indian traditional system of medicine used for kidney disorders.Objectives: The present investigation was undertaken to develop a chromatographically characterized polyherbal combination and to evaluate its nephroprotective activity.Materials and methods: Roots of B. diffusa and R. emodi, flowers of N. nucifera and stem bark of C. nurvala were extracted by decoction using 70% ethanol. Response surface methodology (RSM) was used for the optimization of extraction parameters. Polyherbal combinations with different doses (150-300 mg/kg) were tested against methotrexate-induced nephrotoxicity in Wistar rats.Results: The optimized extract contained 27% phenols and 15% flavonoids, which showed 75% 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging potential. Based on the retention time of high-performance liquid chromatography (HPLC) analysis, 17 out of 122 constituents were found common in all extracts and combinations. Two combinations showed significantly higher (p ≤ 0.05) DPPH scavenging potential and xanthine oxidase inhibition. The half maximal inhibitory concentration (IC50) of the best combination for DPPH scavenging and xanthine oxidase inhibition were 80 and 74 µg/mL, respectively. Treatment of methotrexate-induced nephrotoxic rats with polyherbal combination significantly (p ≤ 0.05) improved the kidney function markers, oxidative stress markers and histological parameters.Discussion and conclusion: The developed combination was found to be effective in nephrotoxicity; it can be explored further for the management of drug-induced nephrotoxicity and other chronic kidney diseases.


Asunto(s)
Antioxidantes/farmacología , Enfermedades Renales/prevención & control , Riñón/efectos de los fármacos , Metotrexato/toxicidad , Extractos Vegetales/farmacología , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/química , Simulación por Computador , Riñón/metabolismo , Enfermedades Renales/inducido químicamente , Enfermedades Renales/metabolismo , Masculino , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/química , Ratas Wistar , Xantina Oxidasa/antagonistas & inhibidores
6.
AAPS PharmSciTech ; 19(3): 1377-1391, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29388027

RESUMEN

Statins are widely prescribed for hyperlipidemia, cancer, and Alzheimer's disease but are facing some inherent challenges such as low solubility and drug loading, higher hepatic metabolism, as well as instability at gastric pH. So, relatively higher circulating dose, required for exerting the therapeutic benefits, leads to dose-mediated severe toxicity. Furthermore, due to low biocompatibility, high toxicity, and other regulatory caveats such as product conformity, reproducibility, and stability of conventional formulations as well as preferentially higher bioabsorption of lipids in their favorable cuboidal geometry, enhancement in in vivo biopharmaceutical performance of Rosuvastatin could be well manifested in Quality by Design (QbD) integrated cuboidal-shaped mucoadhesive microcrystalline delivery systems (Limicubes). Here, quality-target-product-profile (QTPPs), critical quality attributes (CQAs), Ishikawa fishbone diagram, and integration of risk management through risk assessment matrix for failure mode and effects analysis (FMEA) followed by processing of Plackett-Burman design matrix using different statistical test for the first time established an approach to substantiate the claims that controlling levels of only these three screened out independent process variables, i.e., Monoolein (B = 800-1100 µL), Poloxamer (C = 150-200 mg), and stirring speed (F = 700-1000 rpm) were statistically significant to modulate and improve the biopharmaceutical performance affecting key attributes, viz., average particle size (Y1 = 1.40-2.70 µ), entrapment efficiency (Y2 = 62.60-88.80%), and drug loading (Y3 = 0.817-1.15%), in QbD-enabled process. The optimal performance of developed Limicubes exhibited an average particle size of 1.8 ± 0.2 µ, entrapment efficiency 80.32 ± 2.88%, and drug loading 0.93 ± 0.08% at the level of 1100 µL (+ 1), 200 mg (+ 1), and 700 rpm (- 1) for Monoolein, Poloxamer, and stirring speed, respectively.


Asunto(s)
Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/métodos , Rosuvastatina Cálcica/administración & dosificación , Rosuvastatina Cálcica/química , Administración Oral , Liberación de Fármacos/fisiología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/química , Inhibidores de Hidroximetilglutaril-CoA Reductasas/metabolismo , Lípidos/química , Tamaño de la Partícula , Reproducibilidad de los Resultados , Medición de Riesgo , Rosuvastatina Cálcica/metabolismo , Solubilidad
7.
J Sep Sci ; 38(4): 592-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25504557

RESUMEN

Erythrocentaurin is a relatively simple natural product present among the members of Gentianaceae. A preparative method for the isolation of erythrocentaurin from the ethyl acetate fraction of Enicostemma littorale using medium-pressure liquid chromatography has been reported. The method consisted of a simple step gradient from 10 to 20% ethyl acetate in n-hexane. Using a 70 × 460 mm Si60 column, this method is capable of processing 20 g of material in <3 h (purity ≈ 97%). The recovery of erythrocentaurin was 87.77%. Estimation of erythrocentaurin in extracts and fractions based on high-pressure thin-layer chromatography was carried out on silica gel 60 F(254) plates with toluene/ethyl acetate/formic acid (80:18:2 v/v/v) as the mobile phase. The densitometric analysis was performed at 230 nm. A well-separated compact band of erythrocentaurin appeared at R(f )0.54 ± 0.04. The analytical method showed good linearity in the concentration range of 200-1500 ng/band with a correlation coefficient of 0.99417. The limits of detection and quantification were found to be ≈60 and ≈180 ng/band, respectively. Erythrocentaurin exhibited a concentration-dependent α-amylase inhibition (IC(50) 1.67 ± 0.28 mg/mL). The outcome of the study should be considered for pharmacokinetic and biotransformation studies involving E. littorale.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/métodos , Gentianaceae/química , Isocumarinas/análisis , Isocumarinas/aislamiento & purificación , Extractos Vegetales/análisis , Extractos Vegetales/aislamiento & purificación , alfa-Amilasas/antagonistas & inhibidores , Inhibidores Enzimáticos/análisis , Inhibidores Enzimáticos/aislamiento & purificación , alfa-Amilasas/análisis
8.
ScientificWorldJournal ; 2014: 274823, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25580455

RESUMEN

The objective of the current work was to develop optimized self-nanoemulsifying drug delivery systems (SNEDDS) and evaluate their in vitro and in vivo performance. The research comprised various studies which includes solubility studies in various vehicles, pseudoternary phase diagram construction, and preparation and characterization of SNEDDS along with in vitro dissolution and in vivo pharmacodynamic profiling. Based on dissolution profile, a remarkable increase in rate of dissolution was observed in comparison with plain drug and marketed formulation. Optimized SNEDDS formulation was composed of Capmul MCM (19.17% w/w), Tween 80 (57.5% w/w), Transcutol P (12.7% w/w), and HCT (4.17% w/w). In vivo pharmacodynamic evaluation in Wistar rats showed considerable increase in pharmacological effect of HCT by SNEDDS formulation as compared with plain HCT.


Asunto(s)
Disponibilidad Biológica , Sistemas de Liberación de Medicamentos , Hidroclorotiazida/administración & dosificación , Hipertensión/tratamiento farmacológico , Administración Oral , Animales , Estabilidad de Medicamentos , Emulsiones/administración & dosificación , Emulsiones/química , Humanos , Hidroclorotiazida/química , Hidroclorotiazida/farmacocinética , Nanopartículas/administración & dosificación , Nanopartículas/química , Ratas
9.
Gels ; 9(7)2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37504393

RESUMEN

The aim of this investigation was to develop and analyze a tacrolimus and thymoquinone co-loaded nanostructured lipid carriers (TAC-THQ-NLCs)-based nanogel as a new combinatorial approach for the treatment of psoriasis. The NLCs were formulated by an emulsification-solvent-evaporation technique using glyceryl monostearate, Capryol 90 (oil), and a mixture of Tween 80 and Span 20 as a solid lipid, liquid lipid, and surfactant, respectively. Their combination was optimized using a three-factor and three-level Box-Behnken design (33-BBD). The optimized TAC-THQ-NLCs were observed to be smooth and spherical with a particle size of 144.95 ± 2.80 nm, a polydispersity index of 0.160 ± 0.021, a zeta potential of -29.47 ± 1.9 mV, and an entrapment efficiency of >70% for both drugs. DSC and PXRD studies demonstrated the amorphous state of TAC and THQ in the lipid matrix of the NLCs. An FTIR analysis demonstrated the excellent compatibility of the drugs with the excipients without interactions. The TAC-THQ-NLC-based nanogel (abbreviated as TAC-THQ-NG) exhibited a good texture profile and good spreadability. The in vitro release study demonstrated a sustained drug release for 24 h from the TAC-THQ-NG that followed the Korsmeyer-Peppas kinetic model with a Fickian diffusion mechanism. Moreover, the TAC-THQ-NG revealed significantly higher dose-dependent toxicity against an HaCaT cell line compared to a TAC-THQ suspension gel (abbreviated as TAC-THQ-SG). Furthermore, the developed formulations demonstrated antioxidant activity comparable to free THQ. Confocal microscopy revealed improved permeation depth of the dye-loaded nanogel in the skin compared to the suspension gel. Based on these findings, it was concluded that TAC-THQ-NG is a promising combinatorial treatment approach for psoriasis.

10.
Int J Pharm ; 642: 123136, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37311498

RESUMEN

Exemestane (EXE), an irreversible aromatase inhibitor, is primarily used as a first-line therapy for estrogen receptor-positive breast cancer patients. However, complex physicochemical characteristics of EXE limit its oral bioavailability (<10%) and anti-breast cancer efficacy. The present study aimed to develop a novel nanocarrier system to improve the oral bioavailability and anti-breast cancer efficacy of EXE. In this perspective, EXE-loaded TPGS-based polymer lipid hybrid nanoparticles (EXE-TPGS-PLHNPs) were prepared by the nanoprecipitation method and evaluated for their potential in improving oral bioavailability, safety, and therapeutic efficacy in the animal model. EXE-TPGS-PLHNPs showed significantly higher intestinal permeation in comparison to EXE-PLHNPs (without TPGS) and free EXE. After oral administration, EXE-TPGS-PLHNPs and EXE-PLHNPs revealed 3.58 and 4.69 times higher oral bioavailability in Wistar rats compared to the conventional EXE suspension. The results of the acute toxicity experiment suggested that the developed nanocarrier was safe for oral administration. Furthermore, EXE-TPGS-PLHNPs and EXE-PLHNPs represented much better anti-breast cancer activity in Balb/c mice bearing MCF-7 tumor xenograft with tumor inhibition rate of 72.72% and 61.94% respectively in comparison with the conventional EXE suspension (30.79%) after 21 days of oral chemotherapy. In addition, insignificant changes in the histopathological examination of vital organs and hematological analysis further confirm the safety of the developed PLHNPs. Therefore, the findings of the present investigation advocated that the encapsulation of EXE in PLHNPs can be a promising approach for oral chemotherapy of breast cancer.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Humanos , Ratas , Animales , Ratones , Femenino , Polímeros/uso terapéutico , Disponibilidad Biológica , Ratas Wistar , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Androstadienos/farmacología , Androstadienos/uso terapéutico , Lípidos
11.
Pharmaceutics ; 15(9)2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37765307

RESUMEN

Risedronate-loaded mPEG-coated hydroxyapatite, thiolated chitosan-based (coated) and non-coated nanoparticles were tested for their potential effects in the treatment of osteoporosis. The prepared nanoparticles were evaluated for their bone-targeting potential by inducing osteoporosis in female Wistar rats via oral administration of Dexona (dexamethasone sodium phosphate). In vivo pharmacokinetic and pharmacodynamic studies were performed on osteoporotic rat models treated with different formulations. The osteoporotic model treated with the prepared nanoparticles indicated a significant effect on bone. The relative bioavailability was enhanced for RIS-HA-TCS-mPEG nanoparticles given orally compared to RIS-HA-TCS, marketed, and API suspension. Biochemical investigations also showed a significant change in biomarker levels, ultimately leading to bone formation/resorption. Micro-CT analysis of bone samples also demonstrated that the RIS-HA-TCS-mPEG-treated group showed the best results compared to other treatment groups. Moreover, the histology of bone treated with RIS-HA-TCS-mPEG showed a marked restoration of the architecture of trabecular bone along with a well-connected bone matrix and narrow inter-trabecular spaces compared to the toxic group. A stability analysis was also carried out according to ICH guidelines (Q1AR2), and it was found that RIS-HA-TCS-mPEG was more stable than RIS-HA-TCS at 25 °C. Thus, the results of present study indicated that mPEG-RIS-HA-TCS has excellent potential for sustained delivery of RIS for the treatment and prevention of osteoporosis, and for minimizing the adverse effects of RIS typically induced via oral administration.

12.
Micromachines (Basel) ; 14(12)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38138351

RESUMEN

Risedronate sodium (RIS) exhibits limited bioavailability and undesirable gastrointestinal effects when administered orally, necessitating the development of an alternative formulation. In this study, mPEG-coated nanoparticles loaded with RIS-HA-TCS were created for osteoporosis treatment. Thiolated chitosan (TCS) was synthesized using chitosan and characterized using DSC and FTIR, with thiol immobilization assessed using Ellman's reagent. RIS-HA nanoparticles were fabricated and conjugated with synthesized TCS. Fifteen batches of RIS-HA-TCS nanoparticles were designed using the Box-Behnken design process. The nanoparticles were formulated through the ionic gelation procedure, employing tripolyphosphate (TPP) as a crosslinking agent. In silico activity comparison of RIS and RIS-HA-TCS for farnesyl pyrophosphate synthetase enzyme demonstrated a higher binding affinity for RIS. The RIS-HA-TCS nanoparticles exhibited 85.4 ± 2.21% drug entrapment efficiency, a particle size of 252.1 ± 2.44 nm, and a polydispersity index of 0.2 ± 0.01. Further conjugation with mPEG resulted in a particle size of 264.9 ± 1.91 nm, a PDI of 0.120 ± 0.01, and an encapsulation efficiency of 91.1 ± 1.17%. TEM confirmed the spherical particle size of RIS-HA-TCS and RIS-HA-TCS-mPEG. In vitro release studies demonstrated significantly higher release for RIS-HS-TCS-mPEG (95.13 ± 4.64%) compared to RIS-HA-TCS (91.74 ± 5.13%), RIS suspension (56.12 ± 5.19%), and a marketed formulation (74.69 ± 3.98%). Ex vivo gut permeation studies revealed an apparent permeability of 0.5858 × 10-1 cm/min for RIS-HA-TCS-mPEG, surpassing RIS-HA-TCS (0.4011 × 10-4 cm/min), RIS suspension (0.2005 × 10-4 cm/min), and a marketed preparation (0.3401 × 10-4 cm/min).

13.
Indian J Med Res ; 135(4): 555-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22664507

RESUMEN

BACKGROUND & OBJECTIVES: Nigella sativa Linn. is extensively used in the Indian diasporas as spice, which may interact with co-administered drugs and affect their intestinal availability. The purpose of this study was to investigate the effect of Nigella on bioavailability of amoxicillin in animal model. METHODS: Everted rat intestinal sacs were used for in vitro experiment to study the transfer of amoxicillin across the gut. Amoxicillin (6 mg/ml) was co-infused with 3 and 6 mg of methanol and hexane extract of Nigella seeds separately. The amount of amoxicillin that traversed the gut was followed spectrophotometrically at 273 nm. For in vivo studies Wistar albino rats were used. Amoxicillin (25 mg/kg, po) was co-administered with hexane extract of Nigella seeds (25 mg/kg, po). The amount of amoxicillin in rat plasma was determined by UPLC-MS/MS method. RESULTS: The in vitro studies both with methanol and hexane extracts of Nigella increased the permeation of amoxicillin significantly (P<0.001) as compared to control. Permeation was also found to be significantly higher for the hexane extract (P<0.001) in comparison to methanol extract at the same dose levels. In vivo experiments revealed that Cmax of amoxicillin in rat plasma when administered orally alone and in combination with hexane extract increased correspondingly from 4138.251 ± 156.93 to 5995.045 ± 196.28 ng/ml while as AUC 0→t increased from 8890.40 ± 143.33 to 13483.46 ± 152.45 ng/ml.h. INTERPRETATION & CONCLUSIONS: Nigella enhanced amoxicillin availability in both in vivo and in vitro studies. As the increase in bioavailability is attributed, in part, to enhanced diffusivity across intestine, our study indicated that Nigella increased intestinal absorption of amoxicillin.


Asunto(s)
Amoxicilina/administración & dosificación , Disponibilidad Biológica , Nigella sativa , Permeabilidad/efectos de los fármacos , Extractos Vegetales , Amoxicilina/sangre , Animales , Interacciones Farmacológicas , Tracto Gastrointestinal/fisiología , Absorción Intestinal/fisiología , Masculino , Nigella sativa/química , Extractos Vegetales/administración & dosificación , Extractos Vegetales/efectos adversos , Extractos Vegetales/química , Ratas , Ratas Wistar , Espectrometría de Masas en Tándem
14.
Pharm Dev Technol ; 17(6): 730-40, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21599490

RESUMEN

The objectives of this research were to evaluate the stability of lercanidipine in solution state and solid state and explore the compatibility of drug with oils, surfactants and cosurfactants as excipients. The effect of pH on the degradation in solution state was studied through pH-rate profile of lercanidipine in constant ionic strength buffer solutions in pH range 1-8 which gives the pH of maximum stability. Powdered lercanidipine was stored under 40°C/0%~75% relative humidities (RH) or 0% RH/5~50°C to study the influence of RH and temperature on the stability of lercanidipine in solid state. Binary mixtures of lercanidipine and different excipients were stored at 40°C/75% RH, 40°C and at room temperature for excipient compatibility evaluation. The degradation of lercanidipine at different pH appears to fit a typical first-order reaction, but in solid state, it does not fit any obvious reaction model. Moisture content and temperature both play important roles affecting the degradation rate. Lercanidipine exhibits good compatibility with surfactants, cosurfactants and oils as excipients under stressed conditions of different storage temperature in a 3-week screening study. Moreover, the proposed high-performance liquid chromatography method was utilized to investigate the kinetics of the acidic and alkaline degradation processes of lercanidipine at different temperatures.


Asunto(s)
Dihidropiridinas/química , Excipientes/química , Soluciones Farmacéuticas/química , Soluciones/química , Estabilidad de Medicamentos , Humedad , Concentración de Iones de Hidrógeno , Cinética , Concentración Osmolar , Polvos/química , Temperatura
15.
Biomed Mater ; 17(6)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36108625

RESUMEN

Cannabidiol (CBD) is a prescribed drug for epilepsy but has low oral bioavailability and gastric instability. Because of the direct link between the nasal cavity and the central nervous system, intranasal administration of CBD as nanoemulsions which are the small sized lipid carriers seem to improve the bioavailability. CBD-nanoemulsions (NEs) were made using Capryol 90, Tween 80, and Transcutol P as oil, surfactant, and co-surfactant, respectively, following aqueous titration approach. Then, using the Box-Behnken design, CBD-NE was statistically optimised for the selection of desirable excipient concentrations in order to create the optimal CBD-NE formulation. As independent variables in the statistical design, Capryol 90 (oil; coded asA), Tween 80 (surfactant; coded asB), and Transcutol P (co-surfactant; coded asC) were used. The dependent variables were droplet size (DS; coded asR1) and polydispersity index (PDI; coded asR2). The average DS, PDI, and the zeta potential of the optimized CBD-NEs were observed to be 88.73 ± 2.67 nm, 0.311 ± 0.015, and -2.71 ± 0.52 mV respectively. Pure CBD and lyophilized CBD-NEFourier-transform infraredspectra demonstrated no physicochemical interaction between excipients and the drug. Furthermore, differential scanning calorimetry and x-ray diffraction measurements revealed the amorphous CBD in the NE. As compared to pure CBD, the optimised CBD-NE showed considerably betterin vitrodrug release as well asex vivonasal permeability. The drug targeting efficiency and direct transport percentage of the optimised CBD-NEs were found to be 419.64% and 76.17%, respectively, in this research. Additionally, pharmacokinetic investigations after intranasal administration of CBD-NE revealed considerably higher drug concentrations in the brain with better brain targeting efficiency. As a result, the development of CBD-NE may be an excellent alternative for better intranasal delivery.


Asunto(s)
Cannabidiol , Nanopartículas , Encéfalo , Sistemas de Liberación de Medicamentos , Emulsiones/química , Glicoles de Etileno , Excipientes/química , Lípidos , Nanopartículas/química , Tamaño de la Partícula , Polímeros , Polisorbatos/química , Glicoles de Propileno , Tensoactivos/química
16.
Pharmaceutics ; 14(9)2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-36145519

RESUMEN

This work aimed to develop dual drug-loaded nanostructured lipid carriers of raloxifene and naringin (RLX/NRG NLCs) for breast cancer. RLX/NRG NLCs were prepared using Compritol 888 ATO and oleic acid using a hot homogenization-sonication method and optimized using central composite design (CCD). The optimized RLX/NRG NLCs were characterized and evaluated using multiple technological means. The optimized RLX/NRG NLCs exhibited a particle size of 137.12 nm, polydispersity index (PDI) of 0.266, zeta potential (ZP) of 25.9 mV, and entrapment efficiency (EE) of 91.05% (raloxifene) and 85.07% (naringin), respectively. In vitro release (81 ± 2.2% from RLX/NRG NLCs and 31 ± 1.9% from the RLX/NRG suspension for RLX and 93 ± 1.5% from RLX/NRG NLCs and 38 ± 2.01% from the RLX/NRG suspension for NRG within 24 h). Concurrently, an ex vivo permeation study exhibited nearly 2.3 and 2.1-fold improvement in the permeability profiles of RLX and NRG from RLX/NRG NLCs vis-à-vis the RLX/NRG suspension. The depth of permeation was proved with CLSM images which revealed significant permeation of the drug from the RLX/NRG NLCs formulation, 3.5-fold across the intestine, as compared with the RLX/NRG suspension. An in vitro DPPH antioxidant study displayed a better antioxidant potential of RLX/NRG in comparison to RLX and NRG alone due to the synergistic antioxidant effect of RLX and NRG. An acute toxicity study in Wistar rats showed the safety profile of the prepared nanoformulations and their excipients. Our findings shed new light on how poorly soluble and poorly permeable medicines can be codelivered using NLCs in an oral nanoformulation to improve their medicinal performance.

17.
J Pak Med Assoc ; 61(6): 597-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22204219

RESUMEN

In the background of the current situation of breast cancer in Pakistan, with its rising incidence and mortality, non affordability and inaccessibility to screening, diagnosis and treatment, Patel Hospital took up the task of addressing these issues at a local level, by initiating an annual free breast camp in the year 2006. In 2008 an inclusion criteria was defined to focus on high risk women for breast cancer. A comparative analysis over a period of three years was done. In the focused camps, in which 28% patients were found to have a positive family history. Most women were symptomatic. Total 11 patients were diagnosed to have cancer after evaluation. Six patients underwent definitive treatment. A problem with lack of awareness, regarding screening and treatment protocols was identified. Family history seems to be an important risk factor in our set up signifying the need to introduce extensive screening programmes.


Asunto(s)
Neoplasias de la Mama , Mamografía , Tamizaje Masivo/métodos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Incidencia , Pakistán/epidemiología , Vigilancia de la Población , Factores de Riesgo , Factores Socioeconómicos
18.
Polymers (Basel) ; 13(21)2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34771389

RESUMEN

The phytogenous alkaloid berberine (BBR) has become a potential drug for the treatment of diabetes, hyperlipidemia, and cancer. However, its therapeutic potential is limited because ofpoor intestinal absorption due to its efflux by the P-gp expressed in the intestinal lumen. Therefore, we aimed to design and fabricate a nanoparticulate system for delivery of BBR employing naturally derived biodegradable and biocompatible polymers, mainly chitosan and alginate, to enhance the oral bioavailability of BBR. A chitosan-alginate nanoparticle system loaded with BBR (BNPs) was formulated by ionic gelation method and was optimized by employing a three-factor, three-level Box-Behnken statistical design. BNPs were characterized for various physicochemical properties, ex vivo, and in vivo evaluations. The optimized BNPs were found to be 202.2 ± 4.9 nm in size, with 0.236 ± 0.02 of polydispersity index, zeta potential -14.8 ± 1.1 mV, and entrapment efficiency of 85.69 ± 2.6%. BNPs showed amorphous nature with no prominent peak in differential scanning calorimetry (DSC) investigation. Similarly, fourier-transform infrared spectroscopy (FTIR) studies did not reveal any interaction between BBR and excipients used. The drug release followed Higuchi kinetics, since these plots demonstrated the highest linearity (R2 = 0.9636), and the mechanism of release was determined to be anomalous or non-Fickian in nature. An ex-vivo gut permeation study showed that BNPs were better internalized into the cells and more highly permeated through the intestine. Furthermore, in vivo pharmacokinetic analysis in female Wistar rats showed a 4.10-fold increase in the oral bioavailability of BBR from BNPs as compared to BBR suspension. With these findings, we have gained new insight into the effective delivery of poorly soluble and permeable drugs via a chitosan-alginate nanoparticle system to improve the therapeutic performance of an oral nanomedicine.

19.
Drug Res (Stuttg) ; 71(3): 122-137, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33167048

RESUMEN

Glioblastoma multiforme (GBM) is the most aggressive and fatal CNS related tumors, which is responsible for about 4% of cancer-related deaths. Current GBM therapy includes surgery, radiation, and chemotherapy. The effective chemotherapy of GBM is compromised by two barriers, i. e., the blood-brain barrier (BBB) and the blood tumor barrier (BTB). Therefore, novel therapeutic approaches are needed. Nanoparticles are one of the highly efficient drug delivery systems for a variety of chemotherapeutics that have gained massive attention from the last three decades. Perfectly designed nanoparticles have the ability to cross BBB and BTB and precisely deliver the chemotherapeutics to GBM tissue/cells. Nanoparticles can encapsulate both hydrophilic and lipophilic drugs, genes, proteins, and peptides, increase the stability of drugs by protecting them from degradation, improve plasma half-life, reduce adverse effects and control the release of drugs/genes at the desired site. This review focussed on the different signaling pathways altered in GBM cells to understand the rationale behind selecting new therapeutic targets, challenges in the drug delivery to the GBM, various transport routes in brain delivery, and recent advances in targeted delivery of different drug and gene loaded various lipidic, polymeric and inorganic nanoparticles in the effective management of GBM.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Encefálicas/terapia , Portadores de Fármacos/química , Terapia Genética/métodos , Glioblastoma/terapia , Nanopartículas/química , Animales , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Glioblastoma/genética , Glioblastoma/patología , Humanos , Lípidos/química , Terapia Molecular Dirigida/métodos , Polímeros/química , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Clin Ophthalmol ; 15: 65-72, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33447011

RESUMEN

PURPOSE: Retinoblastoma presents most commonly as advanced unilateral disease, particularly in developing countries for which primary enucleation has been the preferred method of treatment. However, with the evolution of newer treatment modalities including intravitreal chemotherapy, intra-arterial chemotherapy and newer chemotherapeutic combinations, a trend towards more conservative approaches is being observed. Our aim is to evaluate outcomes of group D eyes following conservative and non-conservative treatment options. PATIENTS AND METHODS: The ocular oncology database was used to identify eyes with unilateral retinoblastoma that fulfilled the International Intraocular Retinoblastoma Classification (IIRC) group D criteria from August 2010 to August 2018 and these were retrospectively reviewed. Overall, 39 eyes were identified. RESULTS: Nineteen (49%) eyes underwent primary enucleation and 20 (51%) received eye-conserving treatment. Eye salvage was possible in 15 (75%) eyes in the attempted salvage group. None of the patient revealed signs of metastasis. All eyes received conventional chemotherapy (carboplatin, vincristine, etoposide) and focal laser therapy. Additional treatment modalities offered included intravitreal chemotherapy, intra-arterial chemotherapy and topotecan. Three (11%) eyes in the primary enucleation group showed high-risk features on histopathology and none developed metastasis. CONCLUSION: The results of the study seem promising and conservative measures can be adopted in selected unilateral group D eyes.

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