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1.
Int Wound J ; 21(3): e14808, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38425135

RESUMO

We evaluated the primary application of crushed prednisolone combined with hydrocolloid powder for clinically diagnosed peristomal pyoderma gangrenosum (PPG). We present our data on this cohort and follow-up of our previous patients. Of the 23 patients who were commenced on this regime, 18 healed (78%). Twenty-two patients commenced on this regime as the primary treatment for their PPG, and for one, it was a rescue remedy after failed conventional therapy. Four patients with significant medical comorbidities failed to heal and one had their stomal reversal surgery before being fully healed. The proposed treatment regime for PPG is demonstrated to be effective, inexpensive and able to be managed in the patient's usual home environment. In vitro drug release analysis was undertaken, and data are presented to provide further insights into the efficacy of this regime.


Assuntos
Prednisolona , Pioderma Gangrenoso , Humanos , Prednisolona/uso terapêutico , Pioderma Gangrenoso/tratamento farmacológico , Pioderma Gangrenoso/etiologia , Pioderma Gangrenoso/diagnóstico , Pós/uso terapêutico , Liberação Controlada de Fármacos , Resultado do Tratamento
2.
Chem Biodivers ; 21(5): e202301880, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38494456

RESUMO

This paper reports on some physicochemical and phytochemical characteristics (i. e. pH, electrical conductivity, colour, moisture content, total phenolic content, sugar profile) and in vitro antioxidant activity of honeys harvested from five legume species, red clover (Trifolium pratense), balansa clover (T. michelianum), Persian clover (T. resupinatum), purple clover (T. purpureum) and sanfoin, also known as holy clover (Onobrychis viciifolia), that were grown in enclosed shade houses to ensure that the honeys' characteristics are reflective of a truly monofloral honey. Glucose and fructose, determined via High-Performance Thin-Layer Chromatography (HPTLC) analysis, were found as the main sugars in all investigated honeys with the ratio of fructose to glucose ranging from 1 : 1.2 to 1 : 1.6. The honeys' pH values ranged from 3.9 to 4.6 which met Codes Alimentarius (CA) requirements. The moisture content was found to be between 17.6 and 22.2 % which in some cases was slightly higher than CA requirements (≤20 %). The honeys' colour values, prior and after filtration, were between 825.5-1149.5 mAU and 532.4-824.8 mAU respectively, illustrating golden yellow to deep yellow hues. The total phenolic content (TPC) of the honeys was determined using a modified Folin-Ciocalteu assay. Their antioxidant activity was captured by the Ferric Reducing-Antioxidant Power (FRAP) assay as well as HPTLC analysis coupled with 2,2-diphenyl-1-picrylhydrazyl (DPPH) derivatisation. The highest total phenolic content was found in red clover honey (45.4 mg GAE/100 g) whereas purple clover honey showed the highest level of activity in the FRAP assay (7.3 mmol Fe2+/kg). HPTLC-DPPH analysis of the honeys' organic extracts demonstrated the presence of various bioactive compounds that contribute to their overall antioxidant activity. This study developed a methodology for producing monofloral clover honeys in a space limited, enclosed production system, which allowed to collate important baseline data for these honeys that can serve as the foundation for their potential future development into commercial honeys, including honeys that can be used for medicinal purposes.


Assuntos
Antioxidantes , Mel , Compostos Fitoquímicos , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/análise , Mel/análise , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/isolamento & purificação , Fenóis/análise , Fenóis/química , Concentração de Íons de Hidrogênio , Trifolium/química , Picratos/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Cromatografia em Camada Fina
3.
Pharmaceutics ; 15(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37242724

RESUMO

Honey has widespread use as a nutritional supplement and flavouring agent. Its diverse bioactivities, including antioxidant, antimicrobial, antidiabetic, anti-inflammatory, and anticancer properties, have also made it an aspirant natural product for therapeutic applications. Honey is highly viscous and very sticky, and its acceptance as a medicinal product will require formulation into products that are not only effective but also convenient for consumers to use. This study presents the design, preparation, and physicochemical characterisation of three types of alginate-based topical formulations incorporating a honey. The honeys applied were from Western Australia, comprising a Jarrah honey, two types of Manuka honeys, and a Coastal Peppermint honey. A New Zealand Manuka honey served as comparator honey. The three formulations were a pre-gel solution consisting of 2-3% (w/v) sodium alginate solution with 70% (w/v) honey, as well as a wet sheet and a dry sheet. The latter two formulations were obtained by further processing the respective pre-gel solutions. Physical properties of the different honey-loaded pre-gel solutions (i.e., pH, colour profile, moisture content, spreadability, and viscosity), wet sheets (i.e., dimension, morphology, and tensile strength) and dry sheets (i.e., dimension, morphology, tensile strength, and swelling index) were determined. High-Performance Thin-Layer Chromatography was applied to analyse selected non-sugar honey constituents to assess the impacts of formulation on the honey chemical composition. This study demonstrates that, irrespective of the honey type utilised, the developed manufacturing techniques yielded topical formulations with high honey content while preserving the integrity of the honey constituents. A storage stability study was conducted on formulations containing the WA Jarrah or Manuka 2 honey. The samples, appropriately packaged and stored over 6 months at 5, 30, and 40 °C, were shown to retain all physical characteristics with no loss of integrity of the monitored honey constituents.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36300690

RESUMO

Glioblastoma is hard to be eradicated partly because of the obstructive blood-brain barrier (BBB) and the dynamic autophagy activities of glioblastoma. Here, hydroxychloroquine (HDX)-loaded yolk-shell upconversion nanoparticle (UCNP)@Zn0.5Cd0.5S nanoparticle coating with the cyclic Arg-Gly-Asp (cRGD)-grafted glioblastoma cell membrane for near-infrared (NIR)-triggered treatment of glioblastoma is prepared for the first time. UCNPs@Zn0.5Cd0.5S (abbreviated as YSN, yolk-shell nanoparticle) under NIR radiation will generate reactive oxygen species for imposing cytotoxicity. HDX, the only available autophagy inhibitor in clinical studies, can enhance cytotoxicity by preventing damaged organelles from being recycled. The cRGD-decorated cell membrane allowed the HDX-loaded nanoparticles to efficiently bypass the BBB and specifically target glioblastoma cells. Exceptional treatment efficacy of the NIR-triggered chemotherapy and photodynamic therapy was achieved in U87 cells and in the mouse glioblastoma model as well. Our results provided proof-of-concept evidence that HDX@YSN@CCM@cRGD could overcome the delivery barriers and achieve targeted treatment of glioblastoma.

5.
Mar Drugs ; 20(5)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35621974

RESUMO

Praziquantel (PZQ) provides an effective treatment against monogenean parasitic infestations in finfish. However, its use as an in-feed treatment is challenging due to palatability issues. In this study, five formulations of PZQ beads (1−4 mm) were developed using marine-based polymers, with allicin added as a flavouring agent. All formulations attained PZQ loading rates ≥74% w/w, and the beads were successfully incorporated into fish feed pellets at an active dietary inclusion level of 10 g/kg. When tested for palatability and digestibility in small yellowtail kingfish, the PZQ-loaded beads produced with alginate-chitosan, alginate-Cremophor® RH40, and agar as carriers resulted in high consumption rates of 99−100% with no digesta or evidence of beads in the gastrointestinal tract (GIT) of fish fed with diets containing either formulation. Two formulations produced using chitosan-based carriers resulted in lower consumption rates of 68−75%, with undigested and partly digested beads found in the fish GIT 3 h post feeding. The PZQ-loaded alginate-chitosan and agar beads also showed good palatability in large (≥2 kg) yellowtail kingfish infected with gill parasites and were efficacious in removing the parasites from the fish, achieving >90% reduction in mean abundance relative to control fish (p < 0.001). The two effective formulations were stable upon storage at ambient temperature for up to 18 months, showing residual drug content >90% compared with baseline levels. Overall, the palatability, efficacy and stability data collected from this study suggest that these two PZQ particulate formulations have potential applications as in-feed anti-parasitic medications for the yellowtail kingfish farming industry.


Assuntos
Anti-Helmínticos , Quitosana , Perciformes , Ágar , Alginatos , Animais , Anti-Helmínticos/farmacologia , Aquicultura , Peixes , Praziquantel/farmacologia , Praziquantel/uso terapêutico
6.
Foods ; 11(8)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35454742

RESUMO

The aim of this review is to provide a comprehensive overview of the large variety of phenolic compounds that have to date been identified in a wide range of monofloral honeys found globally. The collated information is structured along several themes, including the botanical family and genus of the monofloral honeys for which phenolic constituents have been reported, the chemical classes the phenolic compounds can be attributed to, and the analytical method employed in compound determination as well as countries with a particular research focus on phenolic honey constituents. This review covers 130 research papers that detail the phenolic constituents of a total of 556 monofloral honeys. Based on the findings of this review, it can be concluded that most of these honeys belong to the Myrtaceae and Fabaceae families and that Robinia (Robinia pseudoacacia, Fabaceae), Manuka (Leptospermum scoparium, Myrtaceae), and Chestnut (Castanea sp., Fagaceae) honeys are to date the most studied honeys for phenolic compound determination. China, Italy, and Turkey are the major honey phenolic research hubs. To date, 161 individual phenolic compounds belonging to five major compound groups have been reported, with caffeic acid, gallic acid, ferulic acid and quercetin being the most widely reported among them. HPLC with photodiode array detection appears to be the most popular method for chemical structure identification.

7.
Foods ; 10(2)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562382

RESUMO

The use of High-Performance Thin-Layer Chromatography (HPTLC) coupled with the use of DPPH* (2,2-diphenyl-1-picrylhydrazyl) as a derivatisation reagent is a novel approach to the analysis of antioxidant activity of honeys. The method facilitates the visualisation of individual constituents that contribute to the overall antioxidant activity of the honey, even if they are not yet chemically identified, and allows for the quantification of their antioxidant activity as gallic acid equivalents. The method supports a more in-depth study of the antioxidant activity of honey as it allows for a comparative analysis of the antioxidant fingerprints of honeys of different floral origin and is able to capture differences in their individual bioactive constituents. Further, it supports the tracking of changes in antioxidant activity of individual honey constituents over time upon exposure to different temperature conditions, which demonstrates the potential value of the method for in-process quality control.

8.
Theranostics ; 9(15): 4354-4374, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31285766

RESUMO

Gestational trophoblastic neoplasia (GTN), the most aggressive form of which is choriocarcinoma, can result from over-proliferation of trophoblasts. Treating choriocarcinoma requires high doses of systemic chemotherapeutic agents, which result in nonspecific drug distribution and severe toxicity. To overcome these disadvantages and enhance chemotherapeutic efficacy, we synthesized redox- and pH-sensitive, self-assembling, ascorbic acid-derived (PEG-ss-aAPP) micelles to deliver the drug methotrexate (MTX). Methods: We developed and tested self-assembling PEG-ss-aAPP micelles, which release their drug cargo in response to an intracellular reducing environment and the acidity of the early lysosome or tumoral microenvironment. Uptake into JEG3 choriocarcinoma cancer cells was examined using confocal microscopy and transmission electron microscopy. We examined the ability of MTX-loaded PEG-ss-aAPP micelles to inhibit metastasis in an orthotopic mouse model of human choriocarcinoma. Results: Drug-loaded micelles had encapsulation efficiency above 95%. Particles were spherical based on transmission electron microscopy, with diameters of approximately 229.0 nm based on dynamic light scattering. The drug carrier responded sensitively to redox and pH changes, releasing its cargo in specific environments. PEG-ss-aAPP/MTX micelles efficiently escaped from lysosome/endosomes, and they were effective at producing reactive oxygen species, strongly inducing apoptosis and inhibiting invasion and migration. These effects correlated with the ability of PEG-ss-aAPP/MTX micelles to protect IκBα from degradation, which in turn inhibited translocation of NF-κB p65 to the nucleus. In an orthotopic mouse model of human choriocarcinoma, PEG-ss-aAPP/MTX micelles strongly inhibited primary tumor growth and significantly suppressed metastasis without obvious side effects. Conclusions: Our results highlight the potential of PEG-ss-aAPP micelles for targeted delivery of chemotherapeutic agents against choriocarcinoma.


Assuntos
Antineoplásicos/uso terapêutico , Ácido Ascórbico/química , Coriocarcinoma/tratamento farmacológico , Coriocarcinoma/patologia , Metotrexato/uso terapêutico , Micelas , NF-kappa B/metabolismo , Transdução de Sinais , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Glutationa/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Metotrexato/farmacologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Oxirredução , Polietilenoglicóis/química , Espectroscopia de Prótons por Ressonância Magnética , Espécies Reativas de Oxigênio/metabolismo , Succinimidas/química , Distribuição Tecidual/efeitos dos fármacos
9.
Med Res Rev ; 39(2): 561-578, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30136283

RESUMO

Kidney diseases have become a global public health problem. The application of kidney-targeted drug-delivery systems in the management of kidney diseases has profound transformative potential. Kidney-targeted drug delivery can reduce the undesired side effects of often potent drugs and enhance drug efficacy in alleviating the kidney disease. Here, we review the literature on the potential strategies for targeting drugs to the kidneys. Specifically, we provide a broad overview of the targeting vectors and targeting pathways for renal tubules and glomeruli, as well as how the unique structural features of the glomerulus and the receptor-mediated internalization pathways of the tubules allows for drug targeting. Finally, we summarized the literature examples of drug delivery to the kidneys and elaborated strategies suitable for renal targeting to provide new therapeutic approaches for kidney diseases.


Assuntos
Sistemas de Liberação de Medicamentos , Nefropatias/tratamento farmacológico , Glomérulos Renais/efeitos dos fármacos , Túbulos Renais/efeitos dos fármacos , Rim/efeitos dos fármacos , Animais , Anticorpos/química , Taxa de Filtração Glomerular , Humanos , Células-Tronco Mesenquimais/citologia , Nanomedicina , Nanopartículas , Podócitos/citologia , Polímeros/química , Pró-Fármacos
10.
Mol Pharm ; 15(8): 3369-3382, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-29996652

RESUMO

Simple alginate, alginate-stearic acid, and alginate-C18 conjugate nanoparticles and tripolyphosphate-cross-linked chitosan-oleic acid conjugate-coated calcium alginate beads as the vehicle of nanoparticles were designed. Their size, ζ potential, morphology, drug load, drug release, matrix molecular characteristics, mucus penetration, HT-29 cell line cytotoxicity and intracellular trafficking, in vivo blood glucose lowering, and insulin delivery profiles were characterized. Alginate-C18 conjugate nanoparticles were nontoxic. Among all nanoparticle variants, they had reduced size and ζ potential thus enhancing particulate mucus penetration and intracellular trafficking. Their insulin reabsorption tendency was minimized as alginate active COOH/COO- sites were preoccupied with C18. Their loading into coated beads was translated to reduced drug release in simulated gastric phase with nanoparticles being released in the intestinal phase. The combination dosage form increased the blood glucose lowering extent of insulin and blood insulin level compared with nanoparticles or beads alone. Nanoparticles in beads represented a viable approach for oral insulin delivery.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Nanoconjugados/química , Administração Oral , Alginatos/química , Alginatos/farmacologia , Animais , Glicemia/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Diabetes Mellitus Experimental/induzido quimicamente , Liberação Controlada de Fármacos , Absorção Gastrointestinal/efeitos dos fármacos , Células HT29 , Humanos , Hipoglicemiantes/farmacocinética , Insulina/farmacocinética , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Modelos Animais , Ácido Oleico/química , Ácido Oleico/farmacologia , Tamanho da Partícula , Polifosfatos/química , Polifosfatos/farmacologia , Ratos , Ratos Sprague-Dawley , Estreptozocina/toxicidade
11.
Int J Pharm ; 535(1-2): 194-200, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29104056

RESUMO

Harmonized methodologies are urgently required for the taste evaluation of novel pediatric medicines. This study utilized in vitro, in vivo and clinical data to evaluate the palatability of a novel midazolam chocolate tablet. In vitro dissolution experiments showed the crushed tablet to release within 5 min 1.68 mg of midazolam into simulated saliva. This translated to a drug level of 0.84 mg/ml in the oral cavity, which would be higher than the midazolam bitterness detection threshold concentration of 0.03 mg/ml determined in a rat 'brief access taste aversion' (BATA) model. The visual analogue scale scores of patients aged 4-16 years prescribed with midazolam pre-surgery showed a clear preference for the midazolam chocolate tablets (3.35 ± 1.04, n = 20) compared to the control midazolam solution (1.47 ± 0.62, n = 17). The clinical data was in agreement with the in vivo rodent data in showing the novel chocolate tablet matrix to be effective at taste-masking the bitter midazolam.


Assuntos
Chocolate , Comportamento Alimentar/efeitos dos fármacos , Aromatizantes/química , Hipnóticos e Sedativos/administração & dosagem , Midazolam/administração & dosagem , Percepção Gustatória/efeitos dos fármacos , Administração Oral , Adolescente , Animais , Criança , Pré-Escolar , Composição de Medicamentos , Liberação Controlada de Fármacos , Expressão Facial , Humanos , Hipnóticos e Sedativos/química , Injeções Intravenosas , Masculino , Midazolam/química , Estudos Prospectivos , Ratos Sprague-Dawley , Comprimidos
12.
Nanoscale ; 9(35): 13142-13152, 2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-28849826

RESUMO

Ovarian cancer (OC) is the most lethal gynecologic cancer. Survival statistics have show no significant developments over the last three decades, highlighting the fact that current therapeutic strategies require substantial improvements. In this study, we designed a novel folic acid-PEG-conjugated p-phosphonated calix[4]arene nanoparticle (Fp-PCN) for the simultaneous delivery of paclitaxel (PAC) and carboplatin (CAR) at an optimal ratio (5 : 1, mol : mol) to utilize their potential synergistic effect against OC cells. The Fp-PCNs loaded with PAC and CAR (Fp-PCNPAC+CAR) resulted in a remarkable efficacy in the suppression of OC, both in vitro and in vivo. Compared to free drugs, Fp-PCNPAC+CAR showed stronger apoptosis induction as well as invasion and self-renewal capacity suppression in SKOV-3 cells. The molecular mechanism to address the synergism is that Fp-PCNPAC+CAR downregulated JMJD3 expression to modulate the H3K27me3 epigenetic mark of the promoters of HER2 and MYCN. Furthermore, the expressions of JMJD3 and HER2 were significantly associated with poor outcomes for ovarian patients. Our study demonstrates that co-delivery of PAC and CAR can be achieved with the Fp-PCNs, and reveals a previously unrecognized and unexpected role of the JMJD3-HER2 signaling axis in PAC and CAR treatment of OC.


Assuntos
Carboplatina/administração & dosagem , Histona Desmetilases com o Domínio Jumonji/metabolismo , Nanopartículas , Neoplasias Ovarianas/metabolismo , Paclitaxel/administração & dosagem , Receptor ErbB-2/metabolismo , Linhagem Celular Tumoral , Portadores de Fármacos , Epigênese Genética , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Regiões Promotoras Genéticas , Transdução de Sinais
13.
Int J Nanomedicine ; 12: 5673-5686, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848346

RESUMO

Previously, 3,5-dipentadecyloxybenzamidine hydrochloride (TRX-20)-modified liposomes were reported to specifically target mesangial cells (MCs) in glomeruli. To further gain a better understanding of the characteristics and potential application for glomerular diseases of TRX-20-modified liposomes, we synthesized TRX-20 and prepared TRX-20-modified liposomes (TRX-LPs) with different molar ratios - 6% (6%-TRX-LP), 11% (11%-TRX-LP), and 14% (14%-TRX-LP) - of TRX-20 to total lipid in the present study. All TRX-LPs exhibited concentration-dependent toxicity against the MCs at a lipid concentration ranging from 0.01 to 1.0 mg/mL with IC50 values of 3.45, 1.13, and 0.55 mg/mL, respectively. Comparison of the cell viability of TRX-LPs indicated that high levels of TRX-20 caused severe cell mortality, with 11%-TRX-LP showing the higher cytoplasmic accumulation in the MCs. Triptolide (TP) as a model drug was first loaded into 11%-TRX-LP and the liposomes were further modified with PEG5000 (PEG-TRX-TP-LP) in an attempt to prolong their circulation in blood and enhance TP-mediated immune suppression. Due to specific binding to MCs, PEG-TRX-TP-LP undoubtedly showed better anti-inflammatory action in vitro, evidenced by the inhibition of release of nitric oxide (NO) and tumor necrosis factor-α from lipopolysaccharide-stimulated MCs, compared with free TP at the same dose. In vivo, the PEG-TRX-TP-LP effectively attenuated the symptoms of membranous nephropathic (MN) rats and improved biochemical markers including proteinuria, serum cholesterol, and albumin. Therefore, it can be concluded that the TRX-modified liposome is an effective platform to target the delivery of TP to glomeruli for the treatment of MN.


Assuntos
Diterpenos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Rim/efeitos dos fármacos , Lipossomos/administração & dosagem , Lipossomos/química , Fenantrenos/administração & dosagem , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Benzamidinas/química , Células Cultivadas , Diterpenos/química , Diterpenos/farmacologia , Compostos de Epóxi/administração & dosagem , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Ácidos Graxos/química , Glomerulonefrite Membranosa/tratamento farmacológico , Rim/metabolismo , Masculino , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Óxido Nítrico/metabolismo , Fenantrenos/química , Fenantrenos/farmacologia , Polietilenoglicóis/química , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
14.
Sci Rep ; 6: 23489, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27009430

RESUMO

A modular p-phosphonated calix[4]arene vesicle (PCV) loaded with paclitaxel (PTX) and conjugated with folic acid as a cancer targeting ligand has been prepared using a thin film-sonication method. It has a pH-responsive capacity to trigger the release of the encapsulated PTX payload under mildly acidic conditions. PTX-loaded PCV conjugated with alkyne-modified PEG-folic acid ligands prepared via click ligation (fP-PCVPTX) has enhanced potency against folate receptor (FR)-positive SKOV-3 ovarian tumour cells over FR-negative A549 lung tumour cells. Moreover, fP-PCVPTX is also four times more potent than the non-targeting PCVPTX platform towards SKOV-3 cells. Overall, as a delivery platform the PCVs have the potential to enhance efficacy of anticancer drugs by targeting a chemotherapeutic payload specifically to tumours and triggering the release of the encapsulated drug in the vicinity of cancer cells.


Assuntos
Antineoplásicos/farmacologia , Calixarenos/química , Ácido Fólico/farmacologia , Nanoestruturas/química , Paclitaxel/farmacologia , Células A549 , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Fólico/química , Humanos , Concentração de Íons de Hidrogênio , Neoplasias/tratamento farmacológico , Paclitaxel/química
15.
Small ; 12(3): 351-9, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26619362

RESUMO

The paradigm of using nanoparticle-based formulations for drug delivery relies on their enhanced passive accumulation in the tumor interstitium. Nanoparticles with active targeting capabilities attempt to further enhance specific delivery of drugs to the tumors via interaction with overexpressed cellular receptors. Consequently, it is widely accepted that drug delivery using actively targeted nanoparticles maximizes the therapeutic benefit and minimizes the off-target effects. However, the process of nanoparticle mediated active targeting initially relies on their passive accumulation in tumors. In this article, it is demonstrated that these two tumor-targeted drug delivery mechanisms are interrelated and dosage dependent. It is reported that at lower doses, actively targeted nanoparticles have distinctly higher efficacy in tumor inhibition than their passively targeted counterparts. However, the enhanced permeability and retention effect of the tumor tissue becomes the dominant factor influencing the efficacy of both passively and actively targeted nanoparticles when they are administered at higher doses. Importantly, it is demonstrated that dosage is a pivotal parameter that needs to be taken into account in the assessment of nanoparticle mediated targeted drug delivery.


Assuntos
Nanopartículas/química , Ácidos Polimetacrílicos/química , Taxoides/farmacologia , Transferrina/química , Animais , Linhagem Celular Tumoral , Docetaxel , Relação Dose-Resposta a Droga , Endocitose , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Nus , Nanopartículas/ultraestrutura , Baço/efeitos dos fármacos , Baço/metabolismo , Taxoides/uso terapêutico
16.
ACS Omega ; 1(6): 1114-1120, 2016 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30023503

RESUMO

Colloidal poly(glycidyl methacrylate) nanoparticles (NPs) are demonstrated to be platforms facilitating the "click" chemistry approach of surface functionalization for receptor targeting. Folate receptor-targeted NPs were synthesized, physicochemically characterized, confirmed for their biocompatibility, and validated for their selective targeting capabilities for ovarian cancer cells in vitro.

17.
Int J Pharm ; 495(1): 194-203, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26319630

RESUMO

Curcumin (CUR) has been formulated into a host of nano-sized formulations in a bid to improve its in vivo solubility, stability and bioavailability. The aim of this study was to investigate whether the encapsulation of CUR in nanocarriers would impede its biological interactivity, specifically its potential anti-cancer adjuvant activity via the modulation of CYP enzymes in vitro. NanoCUR, a micellar dispersion prepared via a thin film method using only Pluronic F127 as excipient, was amenable to lyophilization, and retained its nano-sized spherical dimensions (17-33 nm) upon reconstitution with water followed by dilution to 5 µM with HBSS or EMEM. NanoCUR was a weaker cytotoxic agent compared to CUR in solution (sCUR), affecting HepG2 cell viability only when the incubation time was prolonged from 4h to 48 h. Correlation with 2h uptake data suggests this was due to a lower cellular uptake rate of CUR from NanoCUR than from sCUR. The poorer CUR accessibility might also account for NanoCUR being a weaker inhibitor of CYP2C9 and CYP2D6 than sCUR. NanoCUR was, however, 1.76-fold more potent against the CYP3A4 (IC50 5.13 ± 0.91 µM) metabolic function. The higher activity against CYP3A4 might be attributed to the synergistic action of Pluronic F127, since the blank micellar dispersion also inhibited CYP3A4 activity. Both sCUR and NanoCUR had no effect on the CYP3A4 mRNA levels in the HepG2 cells. NanoCUR therefore, maintained most of the biological activities of CUR in vitro, albeit at a lower potency and response rate.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Sistema Enzimático do Citocromo P-450/biossíntese , Portadores de Fármacos/química , Nanopartículas/química , Poloxâmero/química , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular , Química Farmacêutica/métodos , Curcumina/administração & dosagem , Repressão Enzimática , Células Hep G2 , Humanos , Micelas , Tamanho da Partícula , Solubilidade , Fatores de Tempo
18.
Anal Bioanal Chem ; 406(11): 2659-67, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24573580

RESUMO

Carboplatin and paclitaxel co-loaded nanovesicles (CPT-PTX-CLV), a novel intravenous formulation void of cremophor EL, may have significant advantages over conventional carboplatin and paclitaxel formulations with respect to tumor targeting, sustained drug release, reduced toxicity, and synergistic efficacy profiles. The aim of this study was to develop and validate a rapid, specific, sensitive, and reliable liquid chromatography-time of flight-mass spectrometry (LC/TOF MS)-based bioanalytical method for the simultaneous quantification of CPT and PTX in a fetal bovine serum (FBS) vehicle containing the dispersed nanovesicles. The analytes were extracted from FBS by simple protein precipitation, with subsequent separation of CPT and PTX on a Waters HPLC SunFire C18 column at a flow rate of 0.25 ml/min using gradient elution mode. The total analytical time was only 12 min. Detection and quantitation was performed by electrospray ionization (ESI) in the positive ionization mode with selective ion monitoring (SIM) at m/z 310.0152 for CPT and 876.3224 for PTX. The calibration curves were linear over the concentration range of 10-4,000 ng/ml for CPT and 5-2,000 ng/ml for PTX (r (2) > 0.99), with the respective lower limit of quantification (LLOQ) at 10 and 5 ng/ml. The intra- and inter-day precision and accuracy of analysis of the quality control samples at low, medium, and high concentration levels were ≤13.6 % relative standard deviation (RSD) and ≤14.6 % relative errors (RE). The rapid, sensitive, and reproducible LC/TOF MS method may be used to support preclinical and clinical pharmacological studies of the CPT-PTX-CLV administered by injection in animal and human cancer models.


Assuntos
Antineoplásicos/sangue , Carboplatina/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Paclitaxel/sangue , Animais , Antineoplásicos/química , Carboplatina/química , Bovinos , Química Farmacêutica , Portadores de Fármacos/química , Estabilidade de Medicamentos , Humanos , Paclitaxel/química
19.
Cancer Lett ; 330(1): 84-95, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23196060

RESUMO

The monoclonal antibody against the AC133 epitope of CD133 has been widely used as a cell surface marker of cancer stem cells in several different cancer types. Here, we describe the isolation and characterisation of two RNA aptamers, including the smallest described 15 nucleotide RNA aptamer, which specifically recognise the AC133 epitope and the CD133 protein with high sensitivity. As well, both these aptamers show superior tumour penetration and retention when compared to the AC133 antibody in a 3-D tumour sphere model. These novel CD133 aptamers will aid future development of cancer stem cell targeted therapeutics and molecular imaging.


Assuntos
Antígenos CD/genética , Aptâmeros de Nucleotídeos/genética , Glicoproteínas/genética , Células-Tronco Neoplásicas/imunologia , Peptídeos/genética , Antígeno AC133 , Antígenos CD/imunologia , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/imunologia , Aptâmeros de Nucleotídeos/isolamento & purificação , Sequência de Bases , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Linhagem Celular Tumoral , Epitopos/genética , Epitopos/imunologia , Regulação Neoplásica da Expressão Gênica , Glicoproteínas/imunologia , Células HT29 , Humanos , Dados de Sequência Molecular , Células-Tronco Neoplásicas/metabolismo , Conformação de Ácido Nucleico , Peptídeos/imunologia , Técnica de Seleção de Aptâmeros/métodos
20.
J Pharm Pharmacol ; 64(10): 1403-11, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22943171

RESUMO

OBJECTIVES: This paper describes the development and optimization of a nanoparticle delivery platform for the anticancer agent, paclitaxel, using a novel amphiphilic carrier, tetrahexyloxy-tetra-p-aminocalix[4]arene (A4C(6) ). METHODS: Nanoparticles were successfully prepared at pH4 by an emulsion evaporation method whereby an organic phase containing paclitaxel: A4C(6) (molar ratio 1:10) was dispersed by probe sonication into an aqueous phase containing 0.5% w/v polyvinyl alcohol as stabilizer. KEY FINDINGS: The drug-loaded nanoparticles had a mean size of 78.7±20.7nm, surface potential of 38.3±7.67mV, and paclitaxel loading and encapsulation efficiencies of 69.1±5.3µg drug/mg carrier and 50.4±3.2%, respectively. Transmission electron micrographs showed discrete particles with no evidence of agglomeration. In-vitro dissolution into phosphate buffered saline supplemented with 4% bovine serum albumin showed 32.7±3.9%, 82.6±5.3% and 91.0±6.0% of the encapsulated paclitaxel load was released at 5, 72 and 120h, respectively. CONCLUSIONS: This is the first report on the use of amino-substituted amphiphilic calixarenes for the encapsulation of anticancer agents. The nanoparticles produced were significantly smaller than, but had comparable drug loads to the Abraxane nanoparticles, and have the potential to achieve targeted delivery of paclitaxel to tumour tissues.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Calixarenos/química , Portadores de Fármacos/química , Nanopartículas , Paclitaxel/administração & dosagem , Paclitaxel Ligado a Albumina , Albuminas/administração & dosagem , Albuminas/química , Antineoplásicos Fitogênicos/química , Sistemas de Liberação de Medicamentos , Excipientes/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Paclitaxel/química , Tamanho da Partícula , Álcool de Polivinil/química , Soroalbumina Bovina/química , Fatores de Tempo
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