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1.
Future Oncol ; 17(29): 3873-3880, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34263659

RESUMEN

The mortality and morbidity rates for prostate cancer have recently increased to alarming levels, rising higher than lung cancer. Due to a lack of drug targets and molecular probes, existing theranostic techniques are limited. Human LIN28A and its paralog LIN28B overexpression are associated with a number of tumors resulting in a remarkable increase in cancer aggression and poor prognoses. The current review aims to highlight recent work identifying the key roles of LIN28A and LIN28B in prostate cancer, and to instigate further preclinical and clinical research in this important area.


Asunto(s)
Terapia Molecular Dirigida , Medicina de Precisión , Neoplasias de la Próstata/terapia , Proteínas de Unión al ARN/metabolismo , Humanos , Masculino , Neoplasias de la Próstata/patología
2.
Int J Food Sci Nutr ; 66(5): 526-32, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26176650

RESUMEN

Powdered infant formula (PIF) can be the sole source of nutrition for babies and infants. Monitoring conformational changes in protein during manufacture of PIF is critical in order to maintain its nutritional value. This study presents the development of a calibration model for monitoring conformational changes in PIF protein by applying a novel multipoint near-infrared (NIR) spectrometry. NIR spectra were collected for PIF and PIF proteins, casein and whey protein isolate, before and after heat treatment. Results show that principal component analysis showed discrimination between native protein at room temperature and protein conformational changes caused at elevated temperature. Partial least squares regression analysis showed good calibration models with correlation coefficients ranging between 87% and 99% for the prediction of protein quality. This novel multipoint NIR spectrometry could serve as a simple in-line tool to rapidly monitor protein quality during processing stages, contributing to product nutritional value.


Asunto(s)
Calibración , Proteínas en la Dieta/química , Fórmulas Infantiles/química , Modelos Químicos , Valor Nutritivo , Estabilidad Proteica , Espectroscopía Infrarroja Corta/métodos , Caseínas/química , Proteínas en la Dieta/normas , Humanos , Lactante , Análisis de los Mínimos Cuadrados , Polvos , Análisis de Componente Principal , Conformación Proteica , Temperatura , Proteína de Suero de Leche/química
3.
Pharm Dev Technol ; 20(4): 394-400, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24397821

RESUMEN

The objective of the present study was to evaluate the influence of Prosolv® and Prosolv®: Mannitol 200 direct compression (DC) fillers on the physicomechanical characteristics of oral dispersible tablets (ODTs) of crystalline atorvastatin calcium. ODTs were formulated by DC and were analyzed for weight uniformity, hardness, friability, drug content, disintegration and dissolution. Three disintegration time (DT) test methods; European Pharmacopoeia (EP) method for conventional tablets (Method 1), a modification of this method (Method 2) and the EP method for oral lyophilisates (Method 3) were compared as part of this study. All ODTs showed low weight variation of <2.5%. Prosolv® only ODTs showed the highest tablet hardness of ∼ 73 N, hardness decreased with increasing mannitol content. Friability of all formulations was <1% although friability of Prosolv®:Mannitol ODTs was higher than for pure Prosolv®. DT of all ODTs was <30 s. Method 2 showed the fastest DT. Method 3 was non-discriminatory giving a DT of 13-15 s for all formulations. Atorvastatin dissolution from all ODTs was >60% within 5 min despite the drug being crystalline. Prosolv® and Prosolv®:Mannitol-based ODTs are suitable for ODT formulations by DC to give ODTs with high mechanical strength, rapid disintegration and dissolution.


Asunto(s)
Anticolesterolemiantes/química , Atorvastatina/química , Excipientes/química , Inhibidores de Hidroximetilglutaril-CoA Reductasas/química , Manitol/química , Administración Oral , Anticolesterolemiantes/administración & dosificación , Atorvastatina/administración & dosificación , Cristalización , Composición de Medicamentos , Dureza , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Solubilidad , Comprimidos
4.
Int J Pharm ; 604: 120717, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34015378

RESUMEN

Our recent study showed that novel infliximab (INF) loaded polyesterurethane (INF-PU) and INF-PU-PEG particulate formulations reduced inflammation in an in-vitro epithelial inflammation model. In this study we investigated therapeutic potential of novel INF-PU and INF-PU-PEG particulate formulations to reduce inflammation in a dextran sodium sulfate (DSS) induced murine model of colitis. Severity of colitis was assessed by measurement of disease activity index (DAI) score, inflammatory markers (neutrophil infiltration, TNFα) and histological score. Treatment groups orally administered with INF-PU and INF-PU-PEG particulate formulations showed improvement in the clinical signs of colitis, similar to that observed with intraperitoneally administered INF, in both, moderate and severe DSS induced colitis model. This was related to a significant reduction in inflammatory cytokines, resulting in a significant reduction in histological score (ANOVA; p < 0.05), indicative of mucosal healing, a key goal of IBD therapy. This could be attributed to its targeted delivery to the inflamed colon and higher permeation of these particulate formulations across the inflamed colonic mucosa, as observed by the confocal images, resulting in local inhibition of TNFα at its site of production. These promising preliminary results warrant further investigation of orally administered INF and its novel particulate formulations in a wider preclinical study.


Asunto(s)
Colitis , Poliuretanos , Animales , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colon , Sulfato de Dextran , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológico , Infliximab , Mucosa Intestinal , Ratones , Ratones Endogámicos C57BL
5.
Future Sci OA ; 7(9): FSO744, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34737885

RESUMEN

The purpose of this review is to highlight recent scientific developments and provide an overview of virus self-assembly and viral particle dynamics. Viruses are organized supramolecular structures with distinct yet related features and functions. Plant viruses are extensively used in biotechnology, and virus-like particulate matter is generated by genetic modification. Both provide a material-based means for selective distribution and delivery of drug molecules. Through surface engineering of their capsids, virus-derived nanomaterials facilitate various potential applications for selective drug delivery. Viruses have significant implications in chemotherapy, gene transfer, vaccine production, immunotherapy and molecular imaging.

7.
Cancers (Basel) ; 12(1)2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31906321

RESUMEN

Piceatannol (PIC) is known to have anticancer activity, which has been attributed to its ability to block the proliferation of cancer cells via suppression of the NF-kB signaling pathway. However, its effect on hypoxia-inducible factor (HIF) is not well known in cancer. In this study, PIC was loaded into bovine serum albumin (BSA) by desolvation method as PIC-BSA nanoparticles (NPs). These PIC-BSA nanoparticles were assessed for in vitro cytotoxicity, migration, invasion, and colony formation studies and levels of p65 and HIF-1α. Our results indicate that PIC-BSA NPs were more effective in downregulating the expression of nuclear p65 and HIF-1α in colon cancer cells as compared to free PIC. We also observed a significant reduction in inflammation induced by chemical colitis in mice by PIC-BSA NPs. Furthermore, a significant reduction in tumor size and number of colon tumors was also observed in the murine model of colitis-associated colorectal cancer, when treated with PIC-BSA NPs as compared to free PIC. The overall results indicate that PIC, when formulated as PIC-BSA NPs, enhances its therpautice potential. Our work could prompt further research in using natural anticancer agents as nanoparticels with possiable human clinical trails. This could lead to the development of a new line of safe and effective therapeutics for cancer patients.

8.
Int J Pharm ; 565: 533-542, 2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31085256

RESUMEN

In this study we examined the potential of novel biodegradable polymers of polyesterurethane (PU), and its PEGylated (PU-PEG) form as nanocarriers of Infliximab (INF), to treat inflammation in an in-vitro epithelial model. Nanoparticles (NPs) formulated were of average size of 200-287 nm. INF loading of NPs (INF-NPs) resulted in an increase in size and zeta potential. No cytotoxicity was observed for any of the NPs. Cellular interaction and uptake of PU NPs were similar compared with polycaprolactone (PCL) NPs and significantly higher to Poly(lactic-co-glycolic) acid (PLGA) NPs. Cellular interaction was higher for corresponding PEG-NPs. INF-PU and INF-PU-PEG NPs showed a rapid rate and extent of recovery of the epithelial barrier function in inflamed Caco-2 cell monolayers and decreased cytokine levels in inflamed monocytes. Results obtained in this study are promising and the potential of PU and PU-PEG NPs for drug delivery and targeting to treat gastrointestinal inflammation warrants further investigation.


Asunto(s)
Antiinflamatorios/administración & dosificación , Portadores de Fármacos/administración & dosificación , Infliximab/administración & dosificación , Nanopartículas/administración & dosificación , Poliuretanos/administración & dosificación , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Humanos , Interleucina-8/inmunología , Mucosa Intestinal/metabolismo , Lipopolisacáridos , Monocitos/efectos de los fármacos , Monocitos/inmunología , Factor de Necrosis Tumoral alfa/inmunología
9.
Curr Pharm Biotechnol ; 17(10): 905-14, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27194359

RESUMEN

The influence of thermal and shear stressors on the stability of the anti-TNF-α monoclonal antibody (mAb), Infliximab® (INF) was investigated. INF at concentrations of 1, 4 and 10 mg/ml was subjected to thermal stress at temperatures of 25-65°C and to shear force by sonication for 1 and 3 minutes. The stressed samples were analysed for physical properties by particle size, zeta potential, for structural integrity by gel electrophoresis (SDS-PAGE) and circular dichroism, INF content by UV spectroscopy and for biological activity by ELISA. Results show no change in physical properties or structural integrity of INF at any concentration tested, when subjected to a temperature of up to 50°C. At 65°C, aggregation and precipitation of INF was observed. When subjected to shear stress, higher concentrations of INF at 4 and 10mg/ml maintained their physical properties and structural integrity. However, the biological activity of INF was found to decrease with increasing temperature and sonication time, and was concentration dependent (ANOVA; p<0.05). Interestingly, lyophilisation of INF at 1mg/ml did not affect its physical properties, structural integrity or its biological activity. These findings have important implications with respect to pharmaceutical processing of INF and mAbs including formulation as polymeric micro and nanoparticle systems for sustained or targeted delivery. These findings also have important implications with respect to the handling and storage of INF and mAbs for clinical use.


Asunto(s)
Anticuerpos Monoclonales/química , Calor , Infliximab/química , Dicroismo Circular , Relación Dosis-Respuesta a Droga , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Electroforesis en Gel de Poliacrilamida , Liofilización , Humanos , Tamaño de la Partícula , Resistencia al Corte , Estrés Mecánico , Factor de Necrosis Tumoral alfa
11.
J Pharm Pharmacol ; 67(4): 525-36, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25515568

RESUMEN

OBJECTIVES: The potential of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) surface modified with octa-arginine (R8) for central nervous system (CNS) delivery was investigated. METHODS: PLGA NPs containing coumarin-6 or loperamide were surface modified using R8 and characterised for size, zeta potential, drug loading and release. We examined the cellular uptake of NPs in Madin-Darby Canine Kidney (MDCK) cells and CNS delivery of loperamide in a mouse model following intranasal (i.n.) and intravenous (i.v.) administration. KEY FINDINGS: NPs were 300-350 nm in diameter and of negative zeta potential which neutralised on R8 conjugation. Cellular uptake of R8-PLGA NPs was rapid compared with PLGA NPs and correlated with a high antinociceptive effect in mice by both the i.n. and i.v. routes. Little antinociceptive effect for PLGA NPs was observed reflecting their slow uptake in the in-vitro cell model. CONCLUSION: This study demonstrates the potential of R8-PLGA NPs as carriers of therapeutic agents to the CNS.


Asunto(s)
Arginina/química , Sistema Nervioso Central , Ácido Láctico/química , Loperamida/administración & dosificación , Nanoconjugados/química , Nanopartículas/química , Ácido Poliglicólico/química , Administración Intranasal , Administración Intravenosa , Analgésicos/administración & dosificación , Analgésicos/farmacología , Animales , Línea Celular , Cumarinas/administración & dosificación , Perros , Sistemas de Liberación de Medicamentos , Femenino , Loperamida/farmacología , Masculino , Ratones Endogámicos C57BL , Tamaño de la Partícula , Poliésteres , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros/química , Tiazoles/administración & dosificación
12.
Int J Pharm Investig ; 4(2): 51-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25006549

RESUMEN

AIM: Spray dried solid dispersion (SDP) of crystalline simvastatin (SIM) in a fast disintegrating matrix of superdisintegrants was studied as a method to enhance SIM dispersibility, rheology, compactibility and compressibility for incorporation into orodispersible tablets (ODTs). MATERIALS AND METHODS: The superdisintegrants investigated were crospovidone (CP), sodium starch glycollate (SSG) and calcium silicate (CS) were spray dried with simvastatin to form SDPs. RESULTS: The SDPs were characterized and the median particle size of SDPs was similar or greater than the SIM, contributing to good rheology of SDPs, while the low bulk density of SDPs indicated a high compactibility. Interestingly electron micrographs for SDPs showed a CP or CS carrier coating of the SIM crystals, contributing to its rheology. Thermal analysis and X-ray diffraction confirmed that SIM was crystalline in the SDPs and no interaction between SIM and any of the carrier(s) was shown by Fourier transform-infra red. Drug content analysis showed a SIM content of 90-95% in SDPs containing CP or CS, while a higher SIM content of 143% was found in SDP containing SSG. When formulated as ODTs, blend containing SIM SDPs in CP showed ease of tableting, regardless of the turret speed. In comparison, tablet blend consisting of a physical mix (PM) of SIM and CP could only be tableted at the lower turret speed of 7 rpm. ODTs formulated using SIM SDPs in CP showed a higher extent of dissolution, compared to the ODTs containing corresponding PM or the commercially available SIM Zocor(®) tablets (ANOVA, P < 0.05). CONCLUSION: SDP using disintegrants as carriers may offer an alternative formulation approach for ODTs of poorly soluble drugs.

13.
Curr Pharm Biotechnol ; 14(2): 220-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23360264

RESUMEN

A major limitation of biological therapeutics is their propensity for degradation particularly in aqueous solutions hence resulting in their short shelf-life. In this study, the stability of trastuzumab (Herceptin®) intravenous (i.v.) solutions, an IgG1 monoclonal antibody (mAb), indicated for the treatment of HER2 positive breast cancer, stored under refrigerated conditions, was evaluated over 28 days. No change in visual appearance or average particle size was observed. The pH values of the trastuzumab i.v. solutions remained stable over time. Interestingly, no change in trastuzumab monomer concentration was observed throughout the 28-day study, as determined by SEC-HPLC. SDSPAGE showed only a monomer band corresponding to the molecular weight of trastuzumab. Circular dichroism spectra obtained following 28-day storage demonstrated integrity of the secondary structural conformation of trastuzumab. Results from this study show that trastuzumab i.v. solutions remain physically and structurally stable on storage at 2-8°C for 28 days. These findings suggest that trastuzumab in solution may not be as sensitive to degradation as expected for a mAb and therefore may have important implications in extending trastuzumab shelf life for clinical use and reducing associated healthcare cost.


Asunto(s)
Anticuerpos Monoclonales Humanizados/química , Administración Intravenosa , Cromatografía Líquida de Alta Presión/métodos , Dicroismo Circular , Estabilidad de Medicamentos , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Soluciones , Estrés Mecánico , Temperatura , Factores de Tiempo , Trastuzumab
14.
Int J Pharm ; 430(1-2): 18-25, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22465631

RESUMEN

A two factor, three level (3(2)) face centred, central composite design (CCD) was applied to investigate the main and interaction effects of tablet diameter and compression force (CF) on hardness, disintegration time (DT) and porosity of mannitol based orodispersible tablets (ODTs). Tablet diameters of 10, 13 and 15 mm, and CF of 10, 15 and 20 kN were studied. Results of multiple linear regression analysis show that both the tablet diameter and CF influence tablet characteristics. A negative value of regression coefficient for tablet diameter showed an inverse relationship with hardness and DT. A positive value of regression coefficient for CF indicated an increase in hardness and DT with increasing CF as a result of the decrease in tablet porosity. Interestingly, at the larger tablet diameter of 15 mm, while hardness increased and porosity decreased with an increase in CF, the DT was resistant to change. The optimised combination was a tablet of 15 mm diameter compressed at 15 kN showing a rapid DT of 37.7s and high hardness of 71.4N. Using these parameters, ODTs containing ibuprofen showed no significant change in DT (ANOVA; p>0.05) irrespective of the hydrophobicity of the ibuprofen.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Excipientes/química , Análisis Factorial , Ibuprofeno/química , Manitol/química , Modelos Químicos , Tecnología Farmacéutica/métodos , Administración Oral , Antiinflamatorios no Esteroideos/administración & dosificación , Compuestos de Calcio/química , Química Farmacéutica , Fuerza Compresiva , Dureza , Interacciones Hidrofóbicas e Hidrofílicas , Ibuprofeno/administración & dosificación , Cinética , Modelos Lineales , Tamaño de la Partícula , Porosidad , Reproducibilidad de los Resultados , Silicatos/química , Solubilidad , Almidón/análogos & derivados , Almidón/química , Comprimidos
15.
Expert Opin Drug Deliv ; 9(12): 1463-74, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23061546

RESUMEN

OBJECTIVE: To examine the potential of a novel 3-fluid nozzle spray drying technology to formulate differentiated layered microparticles (MPs) of diclofenac sodium (DFS)/ethyl cellulose (EC). METHODS: DFS/EC MPs were formulated using the inner and/or outer nozzles of a novel 3-fluid nozzle and compared with MPs formed using conventional (2-fluid) spray drying. MPs were characterised for particle size and for morphology by TEM and SEM. Distribution of DFS and EC of MPs was analysed by FT-IR and DSC. A two-factor, three-level (3(2)) factorial design was applied to investigate the effect and interaction of total feed solid content (TSC) and feed flow rate (FFR) on MP size, D(50%) and D(90%), bulk density and MP yield. RESULTS: Interestingly, TEM demonstrated that MPs formed by 3-fluid nozzle spray drying showed a heterogeneous internal morphology consisting of a core and coat, characteristic of a microcapsule. In comparison, MPs from conventional spray drying showed a homogeneous internal morphology, characteristics of a matrix system. This differential distribution of DFS/EC was supported by FT-IR and DSC. Results of multiple linear regression analysis showed a linear relationship for the effect of TSC and FFR on all responses except for D(50%) where a quadratric model was valid. The effect of TSC/FFR on MP size and yield was similar to conventional spray drying. CONCLUSION: The novel 3-fluid nozzle spray drying offers a new method of designing layered microparticles or microcapsules which can have wide applications from drug stabilisation to controlled drug delivery and targeting.


Asunto(s)
Celulosa/análogos & derivados , Inhibidores de la Ciclooxigenasa/química , Diclofenaco/química , Tecnología Farmacéutica/métodos , Aerosoles , Rastreo Diferencial de Calorimetría , Celulosa/química , Química Farmacéutica/métodos , Portadores de Fármacos , Microscopía Electrónica , Microesferas , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Tecnología Farmacéutica/instrumentación
16.
Clin Ther ; 34(11): 2221-9, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23149007

RESUMEN

BACKGROUND: Administration of medications to pediatric patients is challenging because many drugs are not commercially available in appropriate dosage formulations and/or strengths. Consequently, these drugs are prepared extemporaneously as oral liquid (OL) formulations using marketed tablets or capsules. In many cases, the stability of these extemporaneous preparations, which may affect their tolerability, has not been documented. An alternative extemporaneous solid formulation, such as a fast-dispersing tablet (FDT), may offer enhanced stability as well as dosing flexibility because it may be administered as an orodispersible tablet or as a reconstituted suspension/solution. Although FDTs are available increasingly as patient-friendly oral dosage formulations, and their simple method of manufacture can be applied to extemporaneous formulations, such applications have not been explored to date. OBJECTIVES: The use of extemporaneous captopril OL formulations in hospitals in Ireland was surveyed, and the stability of the most commonly used captopril formulation (reference) was investigated and compared with that of a newly available extemporaneous FDT formulation. METHODS: The survey was carried out in 120 hospitals in the Republic of Ireland. The 56-day stability of the most commonly used formulation was compared with that of a newly available extemporaneous captopril FDT preparation. The captopril content of the formulations was measured by high-performance liquid chromatography analysis. Formulations were also monitored for changes in appearance, including color; odor; and pH (OLs only). RESULTS: The survey showed that extemporaneously prepared captopril OLs were extensively used, particularly in specialist children's hospitals. The most commonly used preparation was a xanthan gum-based oral suspension. Analysis of these OL preparations showed the OLs to have been stable up to day 7, but that the captopril concentration decreased to 72% to 84% at day 14 and to 59% to 68% at day 56; this decrease was accompanied by a pungent odor suggestive of captopril oxidation. In contrast, FDT formulations demonstrated greater stability, with 96% of captopril present at day 56. CONCLUSIONS: The results of this study support only a 7-day stability for the currently dispensed captopril OL in hospitals in Ireland. In contrast, a stability of at least 56 days was shown with the FDTs. The FDTs may represent an alternative and convenient oral solid extemporaneous preparation of captopril and, potentially, other extemporaneous pediatric medications.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/química , Captopril/química , Servicio de Farmacia en Hospital , Pautas de la Práctica en Medicina , Administración Oral , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Captopril/administración & dosificación , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Color , Composición de Medicamentos , Estabilidad de Medicamentos , Utilización de Medicamentos , Dureza , Encuestas de Atención de la Salud , Humanos , Concentración de Iones de Hidrógeno , Irlanda , Oxidación-Reducción , Servicio de Farmacia en Hospital/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Comprimidos , Tecnología Farmacéutica/métodos , Factores de Tiempo
17.
Pharmaceutics ; 3(3): 510-24, 2011 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-24310594

RESUMEN

The aim of the present study was to investigate the influence of process shear stressors on the stability of a model monoclonal antibody, trastuzumab. Trastuzumab, at concentrations of 0.4-4.0 mg/mL, was subjected to sonication, freeze-thaw, lyophilisation, spray drying and was encapsulated into micro- and nanoparticles. The stressed samples were analysed for structural integrity by gel electrophoresis, SDS-PAGE, and size exclusion chromatography (SEC), while the conformational integrity was analysed by circular dichroism (CD). Biological activity of the stressed trastuzumab was investigated by measuring the inhibition of cell proliferation of HER-2 expressing cell lines. Results show that trastuzumab was resistant to the process shear stresses applied and to microencapsulation processes. At the lowest concentration of 0.4 mg/mL, a low percent ( 0.05). The results of this study conclude that trastuzumab may be resistant to various processing stresses. These findings have important implications with respect to pharmaceutical processing of monoclonal antibodies.

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