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1.
Front Glob Womens Health ; 4: 1095112, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547129

RESUMO

Objective: Currently available contraceptive methods do not meet the needs of all users. We sought to explore preferences of potential end-users regarding an on-demand, non-hormonal female contraceptive currently under development, using a web-based survey. Study design: We recruited respondents for an exploratory survey via web link on Amazon Mechanical Turk (MTurk). Individuals were eligible if they were 18-44 years of age, identified as cis-gender female, were English-speaking, not pregnant, and had used barrier contraception previously. Respondents provided demographic characteristics and a basic reproductive history. We then provided a brief description of the potential contraceptive. Respondents were asked about their interest in the proposed contraceptive and preferences for method attributes. Results: A total of 500 respondents completed the survey. Three-quarters of respondents were <35 years of age and 48.2% were currently using a barrier contraceptive method. Three-fourths of respondents (73.8%) expressed interest in using the contraceptive under development. The majority wanted the method to be small (≤2 inches), rod-shaped, and low cost (<$5 per use). More than half (59.4%) said it was important to be able to use the method without partners' knowledge. The most reported potential concerns were vaginal irritation (51.6%) and lack of effectiveness (46.4%). Sixty percent of respondents were confident they could use the method correctly. Discussion: Available contraceptive methods lack attributes preferred by some users. Development of new contraceptives frequently does not involve end-user input early in the development process. Individuals in this sample displayed interest in the proposed contraceptive and expressed preferences that can inform the further development of this method.

2.
Materials (Basel) ; 16(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36676230

RESUMO

The effects of dipole interactions on magnetic nanoparticle magnetization and relaxation dynamics were investigated using five nanoparticle (NP) systems with different surfactants, carrier liquids, size distributions, inter-particle spacing, and NP confinement. Dipole interactions were found to play a crucial role in modifying the blocking temperature behavior of the superparamagnetic nanoparticles, where stronger interactions were found to increase the blocking temperatures. Consequently, the blocking temperature of a densely packed nanoparticle system with stronger dipolar interactions was found to be substantially higher than those of the discrete nanoparticle systems. The frequencies of the dominant relaxation mechanisms were determined by magnetic susceptibility measurements in the frequency range of 100 Hz-7 GHz. The loss mechanisms were identified in terms of Brownian relaxation (1 kHz-10 kHz) and gyromagnetic resonance of Fe3O4 (~1.12 GHz). It was observed that the microwave absorption of the Fe3O4 nanoparticles depend on the local environment surrounding the NPs, as well as the long-range dipole-dipole interactions. These significant findings will be profoundly important in magnetic hyperthermia medical therapeutics and energy applications.

3.
Curr Protein Pept Sci ; 23(12): 862-873, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330647

RESUMO

BACKGROUND: Surfactant protein-S (SP-D) is a naturally occurring lung protein with the potential to treat pulmonary infections. A recombinant surfactant protein-D (SP-D) has been produced and was previously found to exist in multiple oligomeric states. INTRODUCTION: Separation and characterization of interconverting oligomeric states of a protein can be difficult using chromatographic methods, so an alternative separation technique was employed for SPD to characterize the different association states that exist. METHODS: Samples of SP-D were analyzed using asymmetrical flow field-flow fractionation (AF4) using UV and multi-angle laser light scattering (MALLS) detection. The AF4 method appears to be able to separate species as small as the monomer up to the dodecamer (the dominant species) to much larger species with a molar mass greater than 5 MDa. RESULTS: Consistent elution of four distinct peaks was observed after repeated injections. The largest species observed under the last peak (labeled as Peak 4) were termed "unstructured multimers" and were resolved fairly well from the other species. The AF4-MALLS data suggest that only a small fraction of Peak 4 truly corresponds to high molar mass unstructured multimers. All other peaks demonstrated significant molar mass homogeneity consistent with AFM results. CONCLUSION: AF4-MALLS technology appears to be a powerful analytical approach to characterize the complex and dynamic interplay among different protein oligomeric species of SP-D in an aqueous solution.


Assuntos
Multimerização Proteica , Proteína D Associada a Surfactante Pulmonar , Fracionamento por Campo e Fluxo/métodos , Multimerização Proteica/fisiologia , Proteína D Associada a Surfactante Pulmonar/química , Proteínas Recombinantes/química
4.
J Pharm Sci ; 111(12): 3196-3205, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35841999

RESUMO

This publication represents the first to report global information on characteristics and requirements of doctoral programs in the pharmaceutical sciences in schools/colleges of Pharmacy. Survey responses (140 responses) were received from doctoral programs in 23 countries, with the greatest number of responses obtained from Japan, followed by India and the United States. Program characteristics and requirements, and student and faculty information, including graduate placement, in programs in Asia, North America, Europe, Africa and Australia were compared. Survey responses indicated differences in entrance requirements for doctoral programs with minimum requirements being a bachelor's degree, pharmacy degree or master's degree, including a M.Phil. degree. Programs differed widely in size in all geographical areas, but there was a similar emphasis on core educational learning outcomes (core competencies) and Ph.D. graduation requirements including qualifying examinations, thesis defense with internal and external reviewers and requirements for peer-reviewed publications. Additionally, three-quarters of programs indicated that there was external review of their programs every 2-4 or 5-7 years. Female students and female faculty mentors represented about 50% of students/faculty in programs in most geographical areas. Placement of students after graduation indicated that the highest percentage went into the pharmaceutical industry in Asia (predominantly India) and North America, with a lower percentage in Europe, Africa and Australia.


Assuntos
Educação em Farmácia , Feminino , Humanos , África , Europa (Continente) , Inquéritos e Questionários , Estados Unidos , América do Norte , Ásia
5.
J Pharm Sci ; 111(12): 3206-3214, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35842000

RESUMO

Information on master's programs in the pharmaceutical sciences is lacking; this manuscript addresses this gap in the literature, by reporting on the results of an international survey performed in 2021 of master's programs in the pharmaceutical sciences offered at Schools/Colleges of Pharmacy. Ninety-six responses were received from universities from 23 countries, with the greatest number of responses obtained from India, followed by the United States and Japan. Master's programs in the pharmaceutical sciences are generally full time and 2 years in duration. Only 3% of programs were reported to be examination-based, while the remaining 97% had a research component with 70% of programs having a thesis defense with external and/or internal examiners. Master's programs tended to be larger in Asia and Europe than in North America; as well, programs in North America tended to have more international students. Didactic coursework was included in 96% of master's programs in North America, but only in 38% of Asian and 58% of European programs. The predominant placement of graduates from master's programs in Asia was in the pharmaceutical industry (70%); this contrasted with programs in Europe, Africa and North America where 28-36% enter careers in the pharmaceutical industry and higher percentages enter Ph.D. programs. The major challenge identified by programs was funding of faculty and of graduate students, although decreasing career opportunities was identified as a challenge in Asia and Africa.


Assuntos
Farmácia , Humanos , Estados Unidos , Inquéritos e Questionários , Preparações Farmacêuticas , Europa (Continente) , África
6.
Adv Healthc Mater ; 11(2): e2101487, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34738725

RESUMO

Desmoplastic solid tumors are characterized by the rapid build-up of extracellular matrix (ECM) macromolecules, such as hyaluronic acid (HA). The resulting physiological barrier prevents the infiltration of immune cells and also impedes the delivery of anticancer agents. The development of a hypervesiculating Escherichia coli Nissle (ΔECHy) based tumor targeting bacterial system capable of distributing a fusion peptide, cytolysin A (ClyA)-hyaluronidase (Hy) via outer membrane vesicles (OMVs) is reported. The capability of targeting hypoxic tumors, manufacturing recombinant proteins in situ and the added advantage of an on-site OMV based distribution system makes the engineered bacterial vector a unique candidate for peptide delivery. The HA degrading potential of Hy for stromal modulation is combined with the cytolytic activity of ClyA followed by testing it within syngeneic cancer models. ΔECHy is combined with immune checkpoint antibodies and tyrosine kinase inhibitors (TKIs) to demonstrate that remodeling the tumor stroma results in the improvement of immunotherapy outcomes and enhancing the efficacy of biological signaling inhibitors. The biocompatibility of ΔECHy is also investigated to show that the engineered bacteria are effectively cleared, elicit minimal inflammatory and immune responses, and therefore could be a reliable candidate as a live biotherapeutic.


Assuntos
Escherichia coli , Neoplasias , Bactérias , Escherichia coli/química , Humanos , Fatores Imunológicos , Imunoterapia , Neoplasias/tratamento farmacológico
7.
ADMET DMPK ; 9(1): 23-39, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35299876

RESUMO

The WHO Biopharmaceutical Classification System (BCS) is a practical tool to identify active pharmaceutical ingredients (APIs) that scientifically qualify for a waiver of in vivo bioequivalence studies. The focus of this study was to engage a global network of laboratories to experimentally quantify the pH-dependent solubility of the highest therapeutic dose of 16 APIs using a harmonized protocol. Intra-laboratory variability was ≤5 %, and no apparent association of inter-laboratory variability with API solubility was discovered. Final classification "low solubility" vs "high solubility" was consistent among laboratories. In comparison to the literature-based provisional 2006 WHO BCS classification, three compounds were re-classified from "high" to "low-solubility". To estimate the consequences of these experimental solubility results on BCS classification, dose-adjusted in silico predictions of the fraction absorbed in humans were performed using GastroPlus®. Further expansion of these experimental efforts to qualified APIs from the WHO Essential Medicines List is anticipated to empower regulatory authorities across the globe to issue scientifically-supported guidance regarding the necessity of performing in vivo bioequivalence studies. Ultimately, this will improve access to affordable generic products, which is a critical prerequisite to reach Universal Health Coverage.

8.
Front Bioeng Biotechnol ; 9: 808614, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35096795

RESUMO

Exosomes are natural cell-derived nanovesicles of endocytic origin that enable cellular crosstalk by transferring encapsulated molecular cargos across biological barriers, thereby holding significantly complex implications in the etiology and progression of diverse disease states. Consequently, the development of exosomes-based nano-theranostic strategies has received immense consideration for advancing therapeutic interventions and disease prognosis. Their favorable biopharmaceutical properties make exosomes a unique nanoparticulate carrier for pharmaceutical drug delivery. This review provides an update on the contemporary strategies utilizing exosomes for theranostic applications in nanomedicine. In addition, we provide a synopsis of exosomal features and insights into strategic modifications that control in vivo biodistribution. We further discuss their opportunities, merits and pitfalls for cell/tissue targeted drug delivery in personalized nanotherapy.

9.
AAPS PharmSciTech ; 21(3): 88, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32016650

RESUMO

This study tests the hypothesis that association complexes formed between enoxaparin and cetyltrimethylammonium bromide (CTAB) augment permeation across the gastrointestinal mucosa due to improved encapsulation of this hydrophilic macromolecule within biocompatible poly (lactide-co-glycolide, PLGA RG 503) nanoparticles. When compared with free enoxaparin, association with CTAB increased drug encapsulation efficiency within PLGA nanoparticles from 40.3 ± 3.4 to 99.1 ± 1.0%. Drug release from enoxaparin/CTAB PLGA nanoparticles was assessed in HBSS, pH 7.4 and FASSIFV2, pH 6.5, suggesting effective protection of PLGA-encapsulated enoxaparin from unfavorable intestinal conditions. The stability of the enoxaparin/CTAB ion pair complex was pH-dependent, resulting in more rapid dissociation under simulated plasma conditions (i.e., pH 7.4) than in the presence of a mild acidic gastrointestinal environment (i.e., pH 6.5). The intestinal flux of enoxaparin complexes across in vitro Caco-2 cell monolayers was greater when encapsulated within PLGA nanoparticles. Limited changes in transepithelial transport of PLGA-encapsulated enoxaparin complexes in the presence of increasing CTAB concentrations suggest a significant contribution of size-dependent passive diffusion as the predominant transport mechanism facilitating intestinal absorption. Graphical abstract.


Assuntos
Enoxaparina/farmacocinética , Absorção Intestinal , Nanopartículas/química , Células CACO-2 , Enoxaparina/química , Humanos , Permeabilidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química
10.
Int J Pharm ; 548(1): 297-304, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-29981895

RESUMO

Poor aqueous solubility, chemical instability, and indiscriminate cytotoxicity have limited clinical development of camptothecin (CPT) as potent anticancer therapeutic. This research aimed at fabricating thermoresponsive nanocomposites that enhance solubility and stability of CPT in aqueous milieu and enable stimulus-induced drug release using magnetic hyperthermia. 1,2-Dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and l-α-dipalmitoylphosphatidyl glycerol (DPPG) (1:1, mol/mol) were immobilized on the surface of superparamagnetic Fe3O4 nanoparticles (SPIONs) via high affinity avidin-biotin interactions. Heating behavior was assessed using the MFG-1000 magnetic field generator. Encapsulation efficiency and drug release were quantified by fluorescence spectroscopy. Anticancer efficacy of medicated nanoparticles was measured in vitro using Jurkat cells. The results revealed that drug incorporation did not significantly alter particle size, zeta potential, magnetization, and heating properties of lipid-coated SPIONs. Drug loading efficiency was 93.2 ±â€¯5.1%. Drug release from medicated nanoparticles was significantly faster at temperatures above the lipid transition temperature, reaching 37.8 ±â€¯2.6% of incorporated payload after 12 min under therapeutically relevant hyperthermia (i.e., 42 °C). Medicated SPIONs induced greater cytotoxicity than CPT in solution suggesting synergistic activity of magnetically-induced hyperthermia and drug-induced apoptosis. These results underline the opportunity for thermoresponsive phospholipid-coated SPIONs to enable clinical development of highly lipophilic and chemically unstable drugs such as CPT for stimulus-induced cancer treatment.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita/administração & dosagem , 1,2-Dipalmitoilfosfatidilcolina/administração & dosagem , 1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/química , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Humanos , Células Jurkat , Nanopartículas de Magnetita/química , Neoplasias/terapia , Fosfatidilgliceróis/administração & dosagem , Fosfatidilgliceróis/química
11.
Biomicrofluidics ; 12(1): 014110, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29430275

RESUMO

Increasing numbers of animals are diagnosed with thromboembolism, requiring anticoagulation treatment to prevent thrombotic events. Frequent and periodic coagulation monitoring is critical to ensure treatment effectiveness and patient safety by limiting blood coagulation ability within the desired therapeutic range. Point-of-care diagnostics is an ideal candidate for frequent coagulation monitoring due to rapid test results and no need for laboratory setting. This article reports the first utilization of no-reaction lateral flow assay (nrLFA) device for simple and low-cost animal blood coagulation monitoring in resource-limited setting. The nrLFA device consists of sample pad, analytical membrane and wicking pad, without conjugate pad, reagent printing or membrane drying. Citrated and heparinized animal blood were utilized to mimic different blood coagulation abilities in vitro by adding reversal agents CaCl2 and protamine sulfate. The travel distance of red blood cells (RBCs) on the nrLFA after a pre-determined test time serves as endpoint marker. Upon adding 500 mM CaCl2 solution to citrated bovine, canine, rabbit and equine blood, the average travel distance decreases from 10.9 to 9.4 mm, 8.8 to 5.7 mm, 12.6 to 9 mm, and 15.3 to 11.3 mm, respectively. For heparinized bovine and rabbit blood, the average distance decreases from 14.5 to 11.4 mm and from 9.8 to 7.2 mm, respectively, when adding 300 mg/l protamine sulfate solution. The effect of hematocrit on RBC travel distance in the nrLFA was also investigated. The nrLFA device will potentially improve treatment efficiency, patient safety, quality of life, and satisfaction for both animal patients and their owners.

12.
Int J Pharm ; 535(1-2): 148-156, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29104057

RESUMO

Oral bioavailability of the anti-osteoporotic drug alendronate (AL) is limited to ≤ 1% due to unfavorable physicochemical properties. To augment absorption across the gastrointestinal mucosa, an ion pair complex between AL and polyethyleneimine (PEI) was formed and incorporated into nanostructured lipid carriers (NLCs) using a modified solvent injection method. When compared to free AL, ion pairing with PEI increased drug encapsulation efficiency in NLCs from 10% to 87%. Drug release from NLCs measured in vitro using fasted state simulated intestinal fluid, pH 6.5 (FaSSIF-V2) was significantly delayed after PEI complexation. Stability of AL/PEI was pH-dependent resulting in 10-fold faster dissociation of AL in FaSSIF-V2 than measured at pH 7.4. Intestinal permeation properties estimated in vitro across Caco-2 cell monolayers revealed a 3-fold greater flux of AL encapsulated as hydrophobic ion complex in NLCs when compared to AL solution (Papp = 8.43 ± 0.14 × 10-6 cm/s and vs. 2.76 ± 0.42 × 10-6 cm/s). Cellular safety of AL/PEI-containing NLCs was demonstrated up to an equivalent AL concentration of 2.5 mM. These results suggest that encapsulation of AL/PEI in NLCs appears a viable drug delivery strategy for augmenting oral bioavailability of this clinically relevant bisphosphonate drug and, simultaneously, increase gastrointestinal safety.


Assuntos
Alendronato/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Diglicerídeos/química , Portadores de Fármacos/química , Lipídeos/química , Nanoestruturas/química , Polietilenoimina/química , Alendronato/farmacocinética , Conservadores da Densidade Óssea/farmacocinética , Células CACO-2 , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Absorção Intestinal , Mucosa Intestinal/metabolismo
13.
Biomed Microdevices ; 19(3): 64, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28695382

RESUMO

Vitamin K antagonists such as warfarin are the most widely used class of oral anticoagulants. Due to a narrow therapeutic window, patients on warfarin require regular monitoring. Self-testing using point-of-care (POC) diagnostic devices is available, but cost makes this monitoring method beyond reach for many. The main objective of this research was to assess the clinical utility of a low-cost, paper-based lateral flow POC diagnostic device developed for anticoagulation monitoring without the need for a separate electronic reader. Custom-fabricated lateral flow assay (LFA) test strips comprised of a glass fiber sample pad, a nitrocellulose analytical membrane, a cellulose wicking pad, and a plastic backing card were assembled in a plastic cassette. Healthy volunteers and patients on warfarin therapy were recruited for this prospective study. For each participant, a whole blood sample was collected via fingerstick to determine: (1) international normalized ratio (INR) using the CoaguChek® XS coagulometer, (2) hematocrit by centrifugation, and (3) red blood cell (RBC) travel distance on the experimental LFA device after 240 s using digital image analysis. RBC travel distance measured on the LFA device using blood samples obtained from warfarin patients positively correlated with increasing INR value and the LFA device had the capability to statistically distinguish between healthy volunteer INR values and those for patients groups with INR ≥ 2.6. From these data, it is predicted that this low-cost, paper-based LFA device can have clinical utility for identifying anticoagulated patients taking vitamin K antagonists who are outside of the desired therapeutic efficacy window.


Assuntos
Anticoagulantes/farmacologia , Equipamentos para Diagnóstico , Monitoramento de Medicamentos/instrumentação , Dispositivos Lab-On-A-Chip , Papel , Sistemas Automatizados de Assistência Junto ao Leito , Adulto , Idoso , Colódio/química , Custos e Análise de Custo , Equipamentos para Diagnóstico/economia , Monitoramento de Medicamentos/economia , Desenho de Equipamento , Feminino , Humanos , Dispositivos Lab-On-A-Chip/economia , Masculino , Membranas Artificiais , Fitas Reagentes/química
14.
Mater Sci Eng C Mater Biol Appl ; 69: 12-6, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612683

RESUMO

Nanoparticle mediated photothermal ablation of cancerous tissue shows promising results and applicability as a highly efficacious treatment method. As a majority of the photothermal work has been conducted with minimal attenuation of the laser before reaching the nanoparticles within surface seeded tumors in-vivo or through buffered media in-vitro, it is important to understand the effects of greater laser attenuation on photothermal efficacy mediated by changes in the scattering and absorption of the laser. Photothermal efficacy using a near infrared (NIR) 785nm laser irradiating polystyrene (PS) stabilized magnetite (Fe3O4) nanoparticles (PS-Fe3O4) is examined on MDA-MB-231 human mammary gland adenocarcinoma in-vitro. Agarose gel columns of various heights were created to simulate soft tissue and subsequently used for NIR laser attenuation. Polystyrene was found to significantly improve magnetite nanoparticle stability in serum containing media and modified Hank's Balanced Salt Solution and was able to induce significant hyperthermic ablation at mass concentrations which also did not elicit significant innate toxicity. Furthermore it was found that the polystyrene coating significantly reduced innate toxicity over 48h compared to uncoated magnetite. Agar gel layers provided similar optical attenuation in the NIR region to skin and prostate.


Assuntos
Hipertermia Induzida/métodos , Nanopartículas de Magnetita/química , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Meios de Cultura , Feminino , Óxido Ferroso-Férrico/química , Humanos , Raios Infravermelhos , Lasers , Nanopartículas de Magnetita/toxicidade , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Poliestirenos/química
15.
J Pharm Sci ; 105(9): 2489-2497, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26886325

RESUMO

The chairs of each of the 8 Special Interest Groups of the Board of Pharmaceutical Sciences of the International Pharmaceutical Federation have compiled opinions with regard to major challenges for the pharmaceutical sciences over the next 5-10 years. Areas covered are drug design and discovery, natural products, formulation design and pharmaceutical technology, pharmacokinetics/pharmacodynamics and systems pharmacology, translational and personalized medicine, biotechnology, analytical sciences and quality control, and regulatory science.


Assuntos
Biotecnologia/tendências , Descoberta de Drogas/tendências , Sociedades Farmacêuticas , Tecnologia Farmacêutica/tendências , Sistemas de Liberação de Medicamentos , Internacionalidade , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Preparações Farmacêuticas/normas , Farmacocinética
16.
PLoS One ; 10(10): e0140879, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26473479

RESUMO

Low birth weight is associated with both short term problems and the fetal programming of adult onset diseases, including an increased risk of obesity, diabetes and cardiovascular disease. Placental insufficiency leading to intrauterine growth restriction (IUGR) contributes to the prevalence of diseases with developmental origins. Currently there are no therapies for IUGR or placental insufficiency. To address this and move towards development of an in utero therapy, we employ a nanostructure delivery system complexed with the IGF-1 gene to treat the placenta. IGF-1 is a growth factor critical to achieving appropriate placental and fetal growth. Delivery of genes to a model of human trophoblast and mouse placenta was achieved using a diblock copolymer (pHPMA-b-pDMAEMA) complexed to hIGF-1 plasmid DNA under the control of trophoblast-specific promoters (Cyp19a or PLAC1). Transfection efficiency of pEGFP-C1-containing nanocarriers in BeWo cells and non-trophoblast cells was visually assessed via fluorescence microscopy. In vivo transfection and functionality was assessed by direct placental-injection into a mouse model of IUGR. Complexes formed using pHPMA-b-pDMAEMA and CYP19a-923 or PLAC1-modified plasmids induce trophoblast-selective transgene expression in vitro, and placental injection of PLAC1-hIGF-1 produces measurable RNA expression and alleviates IUGR in our mouse model, consequently representing innovative building blocks towards human placental gene therapies.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Fator de Crescimento Insulin-Like I/biossíntese , Insuficiência Placentária/terapia , Trofoblastos/metabolismo , Animais , Aromatase/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Fator de Crescimento Insulin-Like I/genética , Camundongos , Insuficiência Placentária/genética , Insuficiência Placentária/metabolismo , Insuficiência Placentária/patologia , Gravidez , Proteínas da Gravidez/genética , Regiões Promotoras Genéticas , Trofoblastos/patologia
17.
Mater Sci Eng C Mater Biol Appl ; 46: 97-102, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25491964

RESUMO

The photothermal effect of magnetite (Fe3O4) nanoparticles was characterized by photonic absorption in the near-infrared (NIR) region. Upon laser irradiation at 785 nm, the Fe3O4 nanoparticles generate localized hyperthermia in tumorous lesions, which is an effective strategy for cancer therapy; however, uncoated magnetite possesses an innate toxicity which can lead to drawbacks in the clinical setting. To reduce innate toxicity, a poly(acrylic acid) (PAA) coating on the nanoparticles was investigated in order to determine the alterations to stability and the degree of toxicity in an attempt to create a higher utility vector. It was found that the PAA coating significantly reduced the innate toxicity of the uncoated magnetite. Furthermore, the efficacy of PAA-coated magnetite nanoparticles (PAA-Fe3O4) was investigated for treating MDA-MB-231 (human mammary gland adenocarcinoma) cultures in viable concentration ranges (0.1-0.5mg/ml). An appropriate PAA-Fe3O4 concentration range was then established for inducing significant cell death by hyperthermic ablation, but not through innate toxicity.


Assuntos
Resinas Acrílicas/química , Antineoplásicos/química , Materiais Biocompatíveis/química , Raios Infravermelhos , Nanopartículas de Magnetita/química , Fototerapia , Antineoplásicos/toxicidade , Materiais Biocompatíveis/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lasers , Nanopartículas de Magnetita/toxicidade , Neoplasias/terapia
18.
Mater Sci Eng C Mater Biol Appl ; 42: 52-63, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25063092

RESUMO

In this work, the effect of nanoparticle confinement on the magnetic relaxation of iron oxide (Fe3O4) nanoparticles (NP) was investigated by measuring the hyperthermia heating behavior in high frequency alternating magnetic field. Three different Fe3O4 nanoparticle systems having distinct nanoparticle configurations were studied in terms of magnetic hyperthermia heating rate and DC magnetization. All magnetic nanoparticle (MNP) systems were constructed using equivalent ~10nm diameter NP that were structured differently in terms of configuration, physical confinement, and interparticle spacing. The spatial confinement was achieved by embedding the Fe3O4 nanoparticles in the matrices of the polystyrene spheres of 100 nm, while the unconfined was the free Fe3O4 nanoparticles well-dispersed in the liquid via PAA surface coating. Assuming the identical core MNPs in each system, the heating behavior was analyzed in terms of particle freedom (or confinement), interparticle spacing, and magnetic coupling (or dipole-dipole interaction). DC magnetization data were correlated to the heating behavior with different material properties. Analysis of DC magnetization measurements showed deviation from classical Langevin behavior near saturation due to dipole interaction modification of the MNPs resulting in a high magnetic anisotropy. It was found that the Specific Absorption Rate (SAR) of the unconfined nanoparticle systems were significantly higher than those of confined (the MNPs embedded in the polystyrene matrix). This increase of SAR was found to be attributable to high Néel relaxation rate and hysteresis loss of the unconfined MNPs. It was also found that the dipole-dipole interactions can significantly reduce the global magnetic response of the MNPs and thereby decrease the SAR of the nanoparticle systems.


Assuntos
Temperatura Alta , Campos Magnéticos , Nanopartículas de Magnetita/química , Resinas Acrílicas/química , Anisotropia , Teste de Materiais , Poliestirenos/química , Difração de Raios X
19.
Clin Cancer Res ; 20(1): 199-212, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24170547

RESUMO

PURPOSE: Classical pharmacology allows the use and development of conventional phytomedicine faster and more economically than conventional drugs. This approach should be tested for their efficacy in terms of complementarity and disease control. The purpose of this study was to determine the molecular mechanisms by which nimbolide, a triterpenoid found in the well-known medicinal plant Azadirachta indica, controls glioblastoma growth. EXPERIMENTAL DESIGN: Using in vitro signaling, anchorage-independent growth, kinase assays, and xenograft models, we investigated the mechanisms of its growth inhibition in glioblastoma. RESULTS: We show that nimbolide or an ethanol soluble fraction of A. indica leaves (Azt) that contains nimbolide as the principal cytotoxic agent is highly cytotoxic against glioblastoma multiforme in vitro and in vivo. Azt caused cell-cycle arrest, most prominently at the G1-S stage in glioblastoma multiforme cells expressing EGFRvIII, an oncogene present in about 20% to 25% of glioblastoma multiformes. Azt/nimbolide directly inhibited CDK4/CDK6 kinase activity leading to hypophosphorylation of the retinoblastoma protein, cell-cycle arrest at G1-S, and cell death. Independent of retinoblastoma hypophosphorylation, Azt also significantly reduced proliferative and survival advantage of glioblastoma multiforme cells in vitro and in tumor xenografts by downregulating Bcl2 and blocking growth factor-induced phosphorylation of Akt, extracellular signal-regulated kinase 1/2, and STAT3. These effects were specific because Azt did not affect mTOR or other cell-cycle regulators. In vivo, Azt completely prevented initiation and inhibited progression of glioblastoma multiforme growth. CONCLUSIONS: Our preclinical findings demonstrate nimbolide as a potent anti-glioma agent that blocks cell cycle and inhibits glioma growth in vitro and in vivo.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Encefálicas/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Glioblastoma/metabolismo , Limoninas/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteína do Retinoblastoma/metabolismo , Animais , Azadirachta/química , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/metabolismo , Receptores ErbB/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos Nus , Fosforilação , Extratos Vegetais/farmacologia , Folhas de Planta/química , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Nanoscale Res Lett ; 8(1): 426, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-24134544

RESUMO

Magnetic nanoparticles that are currently explored for various biomedical applications exhibit a high propensity to minimize total surface energy through aggregation. This study introduces a unique, thermoresponsive nanocomposite design demonstrating substantial colloidal stability of superparamagnetic Fe3O4 nanoparticles (SPIONs) due to a surface-immobilized lipid layer. Lipid coating was accomplished in different buffer systems, pH 7.4, using an equimolar mixture of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and l-α-dipalmitoylphosphatidyl glycerol (DPPG). Particle size and zeta potential were measured by dynamic laser light scattering. Heating behavior within an alternating magnetic field was compared between the commercial MFG-1000 magnetic field generator at 7 mT (1 MHz) and an experimental, laboratory-made magnetic hyperthermia system at 16.6 mT (13.7 MHz). The results revealed that product quality of lipid-coated SPIONs was significantly dependent on the colloidal stability of uncoated SPIONs during the coating process. Greatest stability was achieved at 0.02 mg/mL in citrate buffer (mean diameter = 80.0 ± 1.7 nm; zeta potential = -47.1 ± 2.6 mV). Surface immobilization of an equimolar DPPC/DPPG layer effectively reduced the impact of buffer components on particle aggregation. Most stable suspensions of lipid-coated nanoparticles were obtained at 0.02 mg/mL in citrate buffer (mean diameter = 179.3 ± 13.9 nm; zeta potential = -19.1 ± 2.3 mV). The configuration of the magnetic field generator significantly affected the heating properties of fabricated SPIONs. Heating rates of uncoated nanoparticles were substantially dependent on buffer composition but less influenced by particle concentration. In contrast, thermal behavior of lipid-coated nanoparticles within an alternating magnetic field was less influenced by suspension vehicle but dramatically more sensitive to particle concentration. These results underline the advantages of lipid-coated SPIONs on colloidal stability without compromising magnetically induced hyperthermia properties. Since phospholipids are biocompatible, these unique lipid-coated Fe3O4 nanoparticles offer exciting opportunities as thermoresponsive drug delivery carriers for targeted, stimulus-induced therapeutic interventions. PACS: 7550Mw; 7575Cd; 8185Qr.

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