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1.
Assay Drug Dev Technol ; 19(8): 508-525, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34757813

RESUMO

It is hypothesized that L-arginine (ARG) can improve etoposide (VP-16) water solubility while preserving its anticancer activity. Factorial design is used to identify conditions for optimum drug aqueous solubility after freeze-drying. The physicochemical properties of the optimized formulation is further analyzed by X-ray powder diffraction, scanning electron microscopy, proton nuclear magnetic resonance, and fourier transform infrared spectroscopy. Drug stability in formulation is analyzed using mass spectrometry based fragmentation analysis. Liquid chromatography tandem mass spectrometry and cell viability assay on Michigan Cancer Foundation-7 (MCF-7) cell line are performed to assess the drug cellular uptake and the anticancer activity, respectively. At the VP-16: ARG ratio of 4:10 (w/w), the drug apparent solubility increased significantly (∼65-folds) with a 3.5-fold improvement in the drug dissolution rate. The interaction between VP-16 and ARG transforms the drug from crystalline to amorphous solid state. VP-16-ARG complex in lower native drug concentration range (50-300 µM) has lower anticancer activity compared with native VP-16, due to reduced intracellular transport of the more hydrophilic complex as indicated by the cell viability assay and confirmed by cell uptake study. However, at higher drug concentrations (500 µM) the complex's higher anticancer activity is ascribed to the synergistic effect between ARG and VP-16. These data suggest that an optimal ARG concentration can have positive effects with potential benefits for chemotherapy.


Assuntos
Arginina , Água , Arginina/química , Varredura Diferencial de Calorimetria , Composição de Medicamentos , Etoposídeo/farmacologia , Solubilidade , Água/química
2.
Assay Drug Dev Technol ; 19(8): 526-538, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34813380

RESUMO

It is hypothesized that etoposide/VP-16 nanomicellar formulation (VP-16 NMF) utilizing D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) can improve etoposide solubility and anticancer activity. The following four different concentrations of TPGS: 3, 6, 8, and 10 wt% were used to solubilize the drug. Among these four formulations, 10 wt% of TPGS loaded with VP-16 NMF dramatically enhanced etoposide apparent solubility by 26-folds compared with the native drug. The physicochemical properties of the optimized formulation were further analyzed by dynamic light scattering, X-ray powder diffraction, scanning electron microscopy, proton nuclear magnetic resonance (1HNMR) and Fourier transform infrared spectroscopy. Liquid chromatography tandem-mass spectrometry (LC-MS/MS) was used to assess solubility and intracellular uptake of the drug from the NMF. Cell viability assay ([3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H tetrazolium solution [MTS]) was performed on MCF-7 and MCF-10A cell lines to assess intracellular uptake and anticancer activity of etoposide. The MTS assay results showed that the VP-16 NMF platform provides a higher anticancer activity than the native VP-16 on the MCF-7 cells line as it integrates a dual anticancer activity of VP-16 and TPGS. LC-MS/MS data showed a threefold increase in cellular uptake of VP-16 NMF in MCF-7 cell line compared with the native etoposide. These data suggest that an optimal TPGS concentration can improve VP-16 bioavailability and efficacy with potential benefits for chemotherapy.


Assuntos
Espectrometria de Massas em Tandem , Disponibilidade Biológica , Cromatografia Líquida , Etoposídeo/farmacologia , Humanos , Solubilidade
3.
Eur Arch Otorhinolaryngol ; 277(12): 3247-3260, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32474648

RESUMO

PURPOSE: To provide a summary of the evidence on the comparative effectiveness of two surgical treatment strategies, sentinel node biopsy (SNB) and elective neck dissection (END), in patients with T1-T2 oral cancer and clinically negative (cN0) neck, in terms of overall survival (OS), disease-free survival (DFS) and neck recurrence rates (NRRs). METHODS: A systematic review was performed by including studies published up to April 2019. Meta-analysis was performed to compare NRRs between SNB and END. A narrative summary of the results was generated for OS, DFS and morbidity outcomes. The certainty of evidence was assessed according to the GRADE methodology. RESULTS: No randomized studies were retrieved. Five observational studies were included in the comparative effectiveness analysis and four observational studies were included in the comparative morbidity analysis. The pooled risk ratio showed no differences in NRRs between SNB and END (10.5% vs 11.6%; pooled RR 1.09; 95% CI 0.67-1.76). No differences in OS or DFS between the two treatments were found. SNB appears to be associated with a lower rate of postoperative complications and lower shoulder dysfunction than END. Conversely, the results of the quality of life (QoL) questionnaires are not sufficient to advocate a particular strategy. CONCLUSION: Our review highlights the lack of well conducted and randomized studies comparing SNB to END, leading to poor clinical evidence. Although our findings suggest no significant differences in OS, DFS and NRR between the two strategies, the certainty of our evidence is too low to make it useful for clinical decision making.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Biópsia de Linfonodo Sentinela , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/cirurgia , Humanos , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/cirurgia , Esvaziamento Cervical , Recidiva Local de Neoplasia , Qualidade de Vida
4.
Mol Pharm ; 16(2): 595-606, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30525661

RESUMO

Many novel vaginal/rectal microbicide formulations failed clinically due to safety concerns, indicating the need for the early investigation of lead microbicide formulations. In this study, the preclinical safety of an HIV-1 gp120 and mannose responsive microbicide delivery system (MRP) is evaluated in C57BL/6 mice. MRP was engineered through the layer-by-layer coating of calcium carbonate (CaCO3) with Canavalia ensiformis lectin (Con A) and glycogen. MRP mean particle diameter and zeta potential were 857.8 ± 93.1 nm and 2.37 ± 4.12 mV, respectively. Tenofovir (TFV) encapsulation and loading efficiencies in MRP were 70.1% and 16.3% w/w, respectively. When exposed to HIV-1 rgp120 (25 µg/mL), MRP released a significant amount of TFV (∼5-fold higher) in vaginal and seminal fluid mixture compared to the control (pre-exposure) level (∼59 µg/mL) in vaginal fluid alone. Unlike the positive control treated groups (e.g., nonoxynol-9), no significant histological damages and CD45+ cells infiltration were observed in the vaginal and major reproductive organ epithelial layers. This was probably due to MRP biocompatibility and its isosmolality (304.33 ± 0.58 mOsm/kg). Furthermore, compared to negative controls, there was no statistically significant increase in pro-inflammatory cytokines such as IL1α, Ilß, IL7, IP10, and TNFα. Collectively, these data suggest that MRP is a relatively safe nanotemplate for HIV-1 gp120 stimuli responsive vaginal microbicide delivery system.


Assuntos
Anti-Infecciosos/uso terapêutico , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Administração Intravaginal , Animais , Carbonato de Cálcio/metabolismo , Quimiocinas/metabolismo , Difusão Dinâmica da Luz , Feminino , Infecções por HIV/tratamento farmacológico , Imuno-Histoquímica , Interleucina-1alfa/metabolismo , Interleucina-1beta/metabolismo , Interleucina-7/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Concentração Osmolar , Tenofovir/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Vagina/virologia
5.
Handchir Mikrochir Plast Chir ; 46(4): 224-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25162240

RESUMO

In the last few years, surgery of the ageing face seems to have shifted from tissue uplifting and tightening to mere filling. We do not agree with this trend. We are positive that ageing brings about 2 basic phenomena: on one hand bone and fat volume reduction, whilst on the other a deterioration of the skin lining (elastosis) leading to an increase in its compliance and extension. We therefore deem of the utmost importance to couple soft tissue filling with indispensable tightening and repositioning together with resection of overabundant skin. For what concerns the mid-face area in particular, we suggest to resort to 3 different lifting techniques, according to the kind of defect to be treated. It is important to take the right pulling vector into consideration as well as the need of skin excess removal. The procedures can be tailored to suit any peculiar need such as malar bag, lower lid border malposition, tear trough deformity, etc. Different cases will be taken into consideration as examples of the various indications and techniques.


Assuntos
Rejuvenescimento , Ritidoplastia/métodos , Tecido Adiposo/transplante , Blefaroplastia/métodos , Cervicoplastia/métodos , Terapia Combinada , Feminino , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Reoperação
6.
AAPS J ; 16(3): 550-67, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24700270

RESUMO

The present work tests the hypothesis that stabilizers have a critical role on nanocarrier stealthiness and anticancer drug efficacy. Two different types of docetaxel (Doc)-loaded nanocapsules (NCs) stabilized with polysorbate 80 (NC(T80)) and polyvinyl alcohol (NC(PVA)) were synthesized using the emulsion solvent diffusion method. These NCs were characterized for particle mean diameter (PMD), drug content, morphology, surface composition, and degree of crystallinity. Furthermore, the cytotoxicity and cellular uptake of the NCs were investigated in MDA-MB 231 cells, THP-1 monocytes, and THP-1-derived macrophages. The optimized spherical NC(T80) had 123.02 ± 14.6 nm, 0.27 ± 0.1, and 101 ± 37.0% for PMD, polydispersity index, and drug encapsulation efficiency, respectively. Doc release kinetics from NC(T80) and NC(PVA) mostly provided better fit to zero-order and Higuchi models, respectively. Powder X-ray diffraction (PXRD) and X-ray photoelectron spectroscopy (XPS) results revealed the presence of amorphous stabilizers on the surface of the NCs. At high drug concentration, the cytotoxicity of NC(T80) was substantially improved (1.3-1.6-fold) compared with that of NC(PVA) in MDA-MB 231 cells. The uptake of both NCs was inhibited by latrunculin A and dynasore, indicating an actin- and dynamin-dependent endocytosis in MDA-MB 231 cells. This occurred via a multifaceted mechanism involving clathrin, caveolin, cytoskeleton, and macropinocytosis. Interestingly, the uptake of NC(PVA) was 2.7-fold greater than that of NC(T80) and occurred through phagocytosis in monocytes and macrophages. This study demonstrates the potential impact of the surface chemistry on the cytotoxicity and phagocytic clearance of nanocarriers for a subsequent improvement of the efficacy of Doc intended for breast cancer chemotherapy.


Assuntos
Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/metabolismo , Nanocápsulas , Fagócitos/metabolismo , Taxoides/metabolismo , Taxoides/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Linhagem Celular Tumoral , Docetaxel , Portadores de Fármacos , Excipientes , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Tamanho da Partícula , Propriedades de Superfície , Taxoides/administração & dosagem
7.
Pharm Res ; 31(9): 2439-52, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24643931

RESUMO

PURPOSE: It is hypothesized that docetaxel (Doc)-loaded hyaluronic acid (HA)-polyethylene glycol/poly(ε-caprolactone)-grafted oily core nanocapsules (NCs) can enhance the drug cytotoxicity and uptake in CD44 expressing breast cancer (BC) cells (MDA-MB 231). METHODS: NCs were prepared, optimized and characterized by dynamic light scattering, transmission electron microscopy (TEM), and powder X-ray diffraction (PXRD). In vitro cytotoxicity tests [MTS, level of reactive oxygen species (ROS) and level of reduced glutathione (GSH)] were performed in BC cells. The contribution of CD44 to the NCs cellular uptake was elucidated using an anti CD44 antibody blockage and a CD44 negative NIH3T3 cell line. RESULTS: The optimum formulation of Doc-loaded HA oily core NCs had respective mean diameter, polydispersity, and drug encapsulation efficiency of 224.18 nm, 0.32, and 60.38%. The NCs appeared spherical with low drug crystallinity, while the drug release data fitted to first order equation. Compared to that of ungrafted NCs, the cytotoxicity of Doc-loaded HA-grafted NCs was significantly enhanced (p<0.05). A decrease of the intracellular level of ROS was reversely correlated with that of GSH. Interestingly, the cellular internalization of HA-grafted NCs mediated CD44 was dramatically enhanced (3 to 4-fold) with respect to the absence of specific biomarker or targeting ligand. CONCLUSIONS: The use of HA-grafted NCs enhanced the selective drug payload, cytotoxicity and uptake in MDA-MB 231 cells. Therefore, it could be a promising template for safe and effective delivery of Doc and similar chemotherapeutic agents in cancer cells.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Ácido Hialurônico/química , Nanocápsulas/química , Taxoides/administração & dosagem , Taxoides/farmacocinética , Animais , Antineoplásicos/farmacologia , Mama/efeitos dos fármacos , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Docetaxel , Feminino , Humanos , Camundongos , Células NIH 3T3 , Nanocápsulas/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Taxoides/farmacologia
8.
Genet Couns ; 24(1): 13-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23610861

RESUMO

We report on a preterm neonate with a deletion of the distal short arm of chromosome 5p15.33 and partial trisomy of the distal short arm of chromosome 3p24.3. The patient was the first-born monozygotic twin. There were no pertinent facial or physical features except a small lower lip hemangioma. The neonate presented with cardiac defects, which included a patent ductus arteriosus, an atrial septal defect and ventricular septal defects. After 94 days of age, however, the patient died from superior vena cava syndrome, recurrent chylothoraces and generalized anasarca. Array comparative genomic hybridization (aCGH) using a custom oligonucleotide microarray (Agilent 180,000 probe platform revealed a terminal duplication of 1,128 oligonucleotide probes from 3pter to 3p24.3, spanning approximately 20.4 megabases (Mb), and a terminal deletion of 271 oligonucleotide probes from 5pter to 5p15.33, spanning approximately 4.3 Mb. This is the first report of a patient with partial trisomy 3p24.3 and partial monosomy 5p15.33 without major dysmorphic features.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 5/genética , Doenças em Gêmeos/genética , Trissomia/genética , Quilotórax/complicações , Quilotórax/diagnóstico , Hibridização Genômica Comparativa/métodos , Doenças em Gêmeos/diagnóstico , Permeabilidade do Canal Arterial/complicações , Permeabilidade do Canal Arterial/diagnóstico , Edema/complicações , Edema/diagnóstico , Evolução Fatal , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Comunicação Interatrial/complicações , Comunicação Interatrial/diagnóstico , Comunicação Interventricular/complicações , Comunicação Interventricular/diagnóstico , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Síndrome da Veia Cava Superior/complicações , Síndrome da Veia Cava Superior/diagnóstico , Trissomia/diagnóstico , Gêmeos Monozigóticos
9.
Transplant Proc ; 45(1): 402-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23375329

RESUMO

Critical limb ischemia (CLI), a vascular disease affecting lower limbs, with high morbidity and mortality, is becoming a challenge due to the aging of the population. Patients without direct revascularization options have the worst outcomes. To date, 25% to 40% of CLI patients are not candidates for surgical or endovascular approaches, facing a major amputation as the ultimate option. This study sought to assess the safety and efficacy of transplantation of autologous bone marrow concentrates in "no-option" patients to restore blood perfusion by collateral flow and limb salvage. We performed a nonrandomized, noncontrolled pilot study for no-option CLI patients using intra-arterial infusion of autologous bone marrow concentrate. Variation of blood perfusion parameters, evaluated by laser doppler flowmetry after 6 and 12 months, was set as primary endpoint. Thirteen enrolled patients showed improvements in objective measurements of perfusion. This uncontrolled study provided evidence that transplantation of autologous bone marrow concentrates was well tolerated by CLI patients without significant adverse effects, demonstrating improved perfusion, confirming the feasibility and safety of the procedure.


Assuntos
Transplante de Medula Óssea/métodos , Extremidades/patologia , Isquemia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Medula Óssea/patologia , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Leucócitos Mononucleares/citologia , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/patologia , Projetos Piloto , Transplante Autólogo/métodos
10.
J Biol Regul Homeost Agents ; 26(1): 67-79, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22475098

RESUMO

Peripheral arterial disease (PAD) is a chronic condition caused by atherosclerosis and is a severe complication of type 2 diabetes (T2D). We hypothesised that chronic condition of arterial disease engenders inflammation and endothelial damage in response to circulating cytokines released in the blood stream of PAD patients. We explored the levels of circulating cytokines in PAD patients with and without diabetes by multiplex cytokine array compared with non-PAD controls. Serum from PAD patients with or without diabetes showed high levels of VEGF, IFN-gamma, TNF-alpha, MCP-1, and EGF. VEGF levels correlated with TNF-alpha and IFN-gamma, significantly. Endothelial cells (ECs) were exposed to the different altered cytokines to evaluate changes in cell growth, migration and tubule-like formation, displaying impairment on proliferation, migration and tubule formation. Our findings demonstrate that a set of cytokines is significantly increased in the serum of PAD patients. These cytokines act to induce endothelial dysfunction synergistically. VEGF strongly correlated with TNF-alpha and IFN-gamma, opening new therapeutic perspectives.


Assuntos
Citocinas/sangue , Endotélio Vascular/fisiopatologia , Doença Arterial Periférica/sangue , Doença Arterial Periférica/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Hipóxia Celular , Movimento Celular , Proliferação de Células , Quimiocina CCL2/sangue , Citocinas/farmacologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/citologia , Fator de Crescimento Epidérmico/sangue , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Interferon gama/sangue , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/etiologia , Fator de Necrose Tumoral alfa/sangue , Fator A de Crescimento do Endotélio Vascular/sangue
11.
Stem Cells Cloning ; 5: 5-14, 2012 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-24198534

RESUMO

Inadequate blood supply to tissues caused by obstruction of arterioles and/or capillaries results in ischemic injuries - these injuries can range from mild (eg, leg ischemia) to severe conditions (eg, myocardial infarction, stroke). Surgical and/or endovascular procedures provide cutting-edge treatment for patients with vascular disorders; however, a high percentage of patients are currently not treatable, owing to high operative risk or unfavorable vascular involvement. Therapeutic angiogenesis has recently emerged as a promising new therapy, promoting the formation of new blood vessels by the introduction of bone marrow-derived stem and progenitor cells. These cells participate in the development of new blood vessels, the enlargement of existing blood vessels, and sprouting new capillaries from existing blood vessels, providing evidence of the therapeutic utility of these cells in ischemic tissues. In this review, the authors describe peripheral arterial disease, an ischemic condition affecting the lower extremities, summarizing different aspects of vascular regeneration and discussing which and how stem cells restore the blood flow. The authors also present an overview of encouraging results from early-phase clinical trials using stem cells to treat peripheral arterial disease. The authors believe that additional research initiatives should be undertaken to better identify the nature of stem cells and that an intensive cooperation between laboratory and clinical investigators is needed to optimize the design of cell therapy trials and to maximize their scientific rigor. Only this will allow the results of these investigations to develop best clinical practices. Additionally, although a number of stem cell therapies exist, many treatments are performed outside international and national regulations and many clinical trials have been not registered on databases such as ClinicalTrials.gov or EudraCT. Therefore, more rigorous clinical trials are required to confirm the first hopeful results and to address the challenging issues.

12.
Ann Oncol ; 23(7): 1838-45, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22100694

RESUMO

BACKGROUND: We investigated pretreatment fasting glucose as a predictor of patients' important outcomes in breast and colorectal cancers undergoing targeted therapies. PATIENTS AND METHODS: In a historic cohort of 202 breast and 218 colorectal cancers treated with targeted agents from 1998 to 2009, we used the Kaplan-Meier method and the log-rank test to estimate survival through tertiles of fasting glucose and the Cox proportional hazards model for multivariate analysis stratified by primary site of cancer and including gender, age and body mass index. RESULTS: The median follow-up was 20 months (1-128). At 60 months, 65% of patients in the lowest tertile of fasting glucose did not experiment disease progression compared with 34% in the highest tertile (P=0.001). Seventy-six percent of females in the lowest tertile showed no progression compared with 49% in the top tertiles (P=0.015). In multivariate analysis, fasting glucose was a significant predictor of time to disease progression only in breast cancer patients in the first tertile compared with the third (P=0.017). CONCLUSIONS: We found evidence of a predictive role of pretreatment fasting glucose in the development of resistance in breast cancer patients treated with targeted agents. Prospective studies are warranted to confirm our findings.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Glicemia , Neoplasias da Mama/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Bevacizumab , Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Cetuximab , Neoplasias Colorretais/sangue , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Trastuzumab , Resultado do Tratamento
13.
Nanoscale Res Lett ; 6(1): 630, 2011 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-22168815

RESUMO

This study is designed to test the hypothesis that docetaxel [Doc] containing oily core nanocapsules [NCs] could be successfully prepared with a high percentage encapsulation efficiency [EE%] and high drug loading. The oily core NCs were generated according to the emulsion solvent diffusion method using neutral Labrafac CC and poly(d, l-lactide) [PLA] as oily core and shell, respectively. The engineered NCs were characterized for particle mean diameter, zeta potential, EE%, drug release kinetics, morphology, crystallinity, and cytotoxicity on the SUM 225 breast cancer cell line by dynamic light scattering, high performance liquid chromatography, electron microscopies, powder X-ray diffraction, and lactate dehydrogenase bioassay. Typically, the formation of Doc-loaded, oily core, polyester-based NCs was evidenced by spherical nanometric particles (115 to 582 nm) with a low polydispersity index (< 0.05), high EE% (65% to 93%), high drug loading (up to 68.3%), and a smooth surface. Powder X-ray diffraction analysis revealed that Doc was not present in a crystalline state because it was dissolved within the NCs' oily core and the PLA shell. The drug/polymer interaction has been indeed thermodynamically explained using the Flory-Huggins interaction parameters. Doc release kinetic data over 144 h fitted very well with the Higuchi model (R2 > 0.93), indicating that drug release occurred mainly by controlled diffusion. At the highest drug concentration (5 µM), the Doc-loaded oily core NCs (as a reservoir nanosystem) enhanced the native drug cytotoxicity. These data suggest that the oily core NCs are promising templates for controlled delivery of poorly water soluble chemotherapeutic agents, such as Doc.

14.
Eur J Pharm Biopharm ; 79(3): 526-36, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21736940

RESUMO

This study is designed to test the hypothesis that tenofovir (TNF) or tenofovir disoproxil fumarate (TDF) loaded nanoparticles (NPs) prepared with a blend of poly(lactic-co-glycolic acid) (PLGA) and methacrylic acid copolymer (Eudragit® S-100, or S-100) are noncytotoxic and exhibit significant pH-responsive release of anti-HIV microbicides in the presence of human semen fluid simulant (SFS). After NPs preparation by emulsification diffusion, their size, encapsulation efficiency (EE%), drug release profile, morphology, and cytotoxicity are characterized by dynamic light scattering, spectrophotometry, transmission electron microscopy, and cellular viability assay/transepithelial electrical resistance measurement, respectively. Cellular uptake was elucidated by fluorescence spectroscopy and confocal microscopy. The NPs have an average size of 250 nm, maximal EE% of 16.1% and 37.2% for TNF and TDF, respectively. There is a 4-fold increase in the drug release rate from the 75% S-100 blend in the presence of SFS over 72 h. At a concentration up to 10mg/ml, the PLGA/S-100 NPs are noncytotoxic for 48 h to vaginal endocervical/epithelial cells and Lactobacillus crispatus. The particle uptake (∼ 50% in 24h) by these vaginal cell lines mostly occurred through caveolin-mediated pathway. These data suggest the promise of using PLGA/S-100 NPs as an alternative controlled drug delivery system in intravaginal delivery of an anti-HIV/AIDS microbicide.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/administração & dosagem , Portadores de Fármacos/química , Infecções por HIV , Nanopartículas/química , Organofosfonatos/administração & dosagem , Adenina/administração & dosagem , Adenina/química , Adenina/uso terapêutico , Adenina/toxicidade , Administração Intravaginal , Fármacos Anti-HIV/química , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/toxicidade , Composição de Medicamentos , Células Epiteliais/efeitos dos fármacos , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/química , Lactobacillus/efeitos dos fármacos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Nanopartículas/toxicidade , Organofosfonatos/química , Organofosfonatos/uso terapêutico , Organofosfonatos/toxicidade , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ácidos Polimetacrílicos/química , Solubilidade , Propriedades de Superfície , Tenofovir , Vagina/citologia , Vagina/efeitos dos fármacos , Vagina/microbiologia
15.
Eur J Pharm Sci ; 44(1-2): 57-67, 2011 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-21704704

RESUMO

The objective of this study was to engineer a model anti-HIV microbicide (tenofovir) loaded chitosan based nanoparticles (NPs). Box-Behnken design allowed to assess the influence of formulation variables on the size of NPs and drug encapsulation efficiency (EE%) that were analyzed by dynamic light scattering and UV spectroscopy, respectively. The effect of the NPs on vaginal epithelial cells and Lactobacillus crispatus viability and their mucoadhesion to porcine vaginal tissue were assessed by cytotoxicity assays and fluorimetry, respectively. In the optimal aqueous conditions, the EE% and NPs size were 5.83% and 207.97nm, respectively. With 50% (v/v) ethanol/water as alternative solvent, these two responses increased to 20% and 602 nm, respectively. Unlike small size (182nm) exhibiting burst release, drug release from medium (281 nm) and large (602 nm)-sized NPs fitted the Higuchi (r(2)=0.991) and first-order release (r(2)=0.999) models, respectively. These NPs were not cytotoxic to both the vaginal epithelial cell line and L. crispatus for 48h. When the diameter of the NPs decreased from 900 to 188 nm, the mucoadhesion increased from 6% to 12%. However, the combinatorial effect of EE% and percent mucoadhesion for larger size NPs was the highest. Overall, large-size, microbicide loaded chitosan NPs appeared to be promising nanomedicines for the prevention of HIV transmission.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/administração & dosagem , Quitosana/química , Portadores de Fármacos/química , Nanopartículas/química , Organofosfonatos/administração & dosagem , Adenina/administração & dosagem , Adenina/química , Adesividade , Análise de Variância , Animais , Fármacos Anti-HIV/química , Sobrevivência Celular/efeitos dos fármacos , Quitosana/toxicidade , Portadores de Fármacos/toxicidade , Composição de Medicamentos , Células Epiteliais/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Técnicas In Vitro , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Microscopia Eletrônica de Transmissão , Nanopartículas/toxicidade , Organofosfonatos/química , Tamanho da Partícula , Solubilidade , Propriedades de Superfície , Suínos , Tenofovir , Vagina/efeitos dos fármacos
16.
Clin Ter ; 162(2): 137-49, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-21533321

RESUMO

Since the first cancer chemotherapy use, efforts have been made in identifying drugs with an antitumor specific action, but cancer is a very complex situation to be cured with a single agent, and to increase drugs selective cytotoxicity new agent combinations, or innovative cellular cycle related schedule, or the use of pro-drugs have been developed. Notwithstanding some relevant improvements in results, chemotherapy remains often a palliative approach. The improved knowledge of the biology of cancer, and of molecular mechanisms and specific targets, has recently modified the approach to various tumors. In particular, the identification of a single and specific genetic alteration in some tumors such as myeloid chronic leukaemia or gastrointestinal stromal tumors (GIST) led to the development of imatinib, a "target" drug with a multikinase inhibitor activity towards the specific genetic alteration; this unique opportunity is not applicable to other tumors, because usually tumors have multiple genetic alterations with very complex molecular pathways. The development of drugs with a multitarget action is probably the best approach to the majority of human cancers, but other possibility are the combination of multiple agents, each with known selective activity towards a specific molecular target, or the choice of a chemotherapic drug in combination with one or more molecularly targeted drugs. The knowledge of the multiple and extremely complex molecular pathways of the neoplastic cells will hopefully drive oncologic science towards a more "exact" science, with the use of "personalized" treatment in each cancer patient.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacocinética , Previsões , Humanos , Modelos Teóricos , Terapia de Alvo Molecular , Neoplasias/metabolismo , Distribuição Tecidual
17.
J Pharm Sci ; 100(8): 3345-3356, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21437910

RESUMO

The objective of this study is to engineer polylysine-heparin functionalized solid lipid nanoparticles (fSLNs) for the use of a vaginal microbicide delivery template for HIV prevention. The fSLNs are prepared using a modified phase-inversion technique followed by a layer-by-layer deposition method. The Box-Behnken experimental design is used to analyze the influence of three factors (X(1) = bovine serum albumin concentration, X(2) = pH of the aqueous phase, and X(3) = lipid amount) on the particle mean diameter (PMD) measured by dynamic light scattering (DLS). Tenofovir is used as a model anti-HIV microbicide. The SLNs are also characterized for morphology, zeta potential (ζ ), percent drug encapsulation efficiency (EE%), and cytotoxicity on a human vaginal epithelial cell line by electron microscopy, DLS, ultraviolet, and fluorescence spectroscopy, respectively. The statistical model predicts particle size (Y) with 90% confidence and the Y values are significantly affected by X(1) and X(2) . The produced fSLNs appear noncytotoxic and exhibit a platelet-like shape with respective PMD, EE%, and ζ value of 153 nm, 8.3%, and - 51 mV. These fSLNs intended to be administered topically have the potential to enhance cellular uptake of hydrophobic microbicides and outdistance the virus during the HIV/AIDS infection process, possibly leading to more effective prevention of the disease transmission.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/química , Portadores de Fármacos/química , Infecções por HIV/prevenção & controle , Lipídeos/química , Nanopartículas/química , Organofosfonatos/química , Adenina/química , Adenina/uso terapêutico , Adenina/toxicidade , Administração Intravaginal , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/toxicidade , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/ultraestrutura , Feminino , Heparina/química , Humanos , Microscopia Eletrônica de Transmissão , Organofosfonatos/uso terapêutico , Organofosfonatos/toxicidade , Tamanho da Partícula , Transição de Fase , Polilisina/química , Propriedades de Superfície , Tenofovir , Vagina/efeitos dos fármacos , Vagina/ultraestrutura
18.
J Pharm Sci ; 100(3): 1031-44, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20928871

RESUMO

The formulation variables required for the production of spray-dried oily core nanocapsules (NCs) with targeted size and drug payload were optimized using a Box-Behnken experimental design. These NCs were characterized for size, morphology, encapsulation efficiency (EE%) and drug release kinetics, crystallinity, and density, by dynamic light scattering, electron microscopy, ultraviolet spectrometry, powder X-ray diffraction, and density-gradient centrifugation, respectively. The size of the NCs ranged from 208.6 to 504.4 nm, with EE% from 64.7% to 94.6%. The amounts of oil and surfactant (Pluronic F127) significantly affected size. The amounts of polymer [polylactide (PLA)], oil, and surfactant significantly affected EE%. The optimum formulation parameters were set to be 300 mg of PLA, 0.56 mL of oil, and 239.57 mg of Pluronic F127, which corresponded to size of 284.1 nm and EE% of 95.7%. Morphological analysis and density-gradient centrifugation showed the existence of an oily core and spherical nanostructure with no detectable drug crystals. The NCs had longer sustained drug release than nanosphere control, with a good fit to the Ritger-Peppas model (R(2) > 0.930). Spray-dried oily core NCs were successfully produced, and the Box-Behnken design appears to be an effective tool to predict the size and encapsulation of NCs.


Assuntos
Anti-Inflamatórios não Esteroides/química , Composição de Medicamentos , Indometacina/química , Nanocápsulas , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Cumarínicos , Preparações de Ação Retardada , Excipientes , Indometacina/administração & dosagem , Indometacina/farmacocinética , Nanopartículas , Tamanho da Partícula , Poloxâmero , Poliésteres , Povidona , Dióxido de Silício , Solubilidade , Compostos de Sulfidrila , Propriedades de Superfície , Suspensões
19.
Nanomedicine (Lond) ; 5(9): 1385-99, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21128721

RESUMO

Once metastatic, melanoma remains one of the most aggressive and morbid malignancies. Moreover, in past decades, the overall survival for advanced unresectable melanoma exhibited a constancy of poor prognosis. Low response rates and serious adverse effects have been characteristic of standard therapy based on a combination of chemotherapeutic agents or immunotherapy with IL-2. For example, the chemotherapy including dacarbazine, carmustin, cisplatin and tamoxifen is known as 'Dartmouth regimen' while the CVD regimen comprises carmustine, vinblastine and dacarbazine. Thus, there is an urgent and critical need to reformulate these bioactive agents using nanoscience and nanotechnology as alternative strategies. This article overviews current design and evaluation of nanomedicine undertaken to address this unmet medical need. The nanomedicines studied include polymeric nanoparticles, liposomes, polymersomes, dendrimers, cubosomes, niosomes and nanodiamonds. In this preclinical article, nanotechnology provides hope for effective treatment of this aggressive and largely treatment-resistant disease.


Assuntos
Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Melanoma/tratamento farmacológico , Nanomedicina/métodos , Antineoplásicos/administração & dosagem , Carmustina/administração & dosagem , Carmustina/uso terapêutico , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Dacarbazina/administração & dosagem , Dacarbazina/uso terapêutico , Humanos , Tamoxifeno/administração & dosagem , Tamoxifeno/uso terapêutico
20.
Transplant Proc ; 42(7): 2816-20, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20832596

RESUMO

Restoring blood flow to ischemic tissue is a prerequisite for treatment of ischemic diseases. Cell-based therapy based on bone marrow transplantation is a promising option for patients with critical limb ischemia (CLI). The efficacy of cell therapies to augment neovascularization seems to involve endothelial progenitor cells (EPCs); however, the mechanisms underlying the efficacy have not been fully elucidated. Herein we have described the case of a young patient with severe CLI, who experienced a 24-month beneficial clinical response to autologous bone marrow transplantation. The exceptional amelioration enabled him to perform standardized maximal treadmill exercise test that demonstrated lack of exercise-induced EPC mobilization, despite adequate stromal-derived factor 1 and vascular endothelial growth factor responses. Therefore, tissue ischemia is not sufficient to promote the recruitment of EPCs that have been demonstrated to be involved in the recovery from ischemia. The local implantation of marrow-derived elements may provide cells and/or trophic factors, which have the capacity to augment angiogenesis, opening new approaches to the etiopathogenesis of the disease.


Assuntos
Arteriopatias Oclusivas/complicações , Transplante de Medula Óssea/métodos , Mobilização de Células-Tronco Hematopoéticas/métodos , Isquemia/patologia , Perna (Membro)/irrigação sanguínea , Adulto , Aorta Abdominal/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , HDL-Colesterol/sangue , Humanos , Hiperemia/diagnóstico por imagem , Hiperemia/fisiopatologia , Artéria Ilíaca/diagnóstico por imagem , Isquemia/etiologia , Testes de Função Renal , Testes de Função Hepática , Masculino , Neovascularização Fisiológica , Tomografia Computadorizada por Raios X
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