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1.
Crit Care Med ; 52(7): 1113-1126, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38236075

RESUMO

OBJECTIVES: To provide a narrative review of hospital violence (HV) and its impact on critical care clinicians. DATA SOURCES: Detailed search strategy using PubMed and OVID Medline for English language articles describing HV, risk factors, precipitating events, consequences, and mitigation strategies. STUDY SELECTION: Studies that specifically addressed HV involving critical care medicine clinicians or their practice settings were selected. The time frame was limited to the last 15 years to enhance relevance to current practice. DATA EXTRACTION: Relevant descriptions or studies were reviewed, and abstracted data were parsed by setting, clinician type, location, social media events, impact, outcomes, and responses (agency, facility, health system, individual). DATA SYNTHESIS: HV is globally prevalent, especially in complex care environments, and correlates with a variety of factors including ICU stay duration, conflict, and has recently expanded to out-of-hospital occurrences; online violence as well as stalking is increasingly prevalent. An overlap with violent extremism and terrorism that impacts healthcare facilities and clinicians is similarly relevant. A number of approaches can reduce HV occurrence including, most notably, conflict management training, communication initiatives, and visitor flow and access management practices. Rescue training for HV occurrences seems prudent. CONCLUSIONS: HV is a global problem that impacts clinicians and imperils patient care. Specific initiatives to reduce HV drivers include individual training and system-wide adaptations. Future methods to identify potential perpetrators may leverage machine learning/augmented intelligence approaches.


Assuntos
Cuidados Críticos , Humanos , Cuidados Críticos/métodos , Unidades de Terapia Intensiva , Fatores de Risco , Violência no Trabalho/prevenção & controle , Violência no Trabalho/estatística & dados numéricos , Violência/prevenção & controle
2.
J Med Internet Res ; 25: e44030, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140973

RESUMO

The use of artificial intelligence (AI) and big data in medicine has increased in recent years. Indeed, the use of AI in mobile health (mHealth) apps could considerably assist both individuals and health care professionals in the prevention and management of chronic diseases, in a person-centered manner. Nonetheless, there are several challenges that must be overcome to provide high-quality, usable, and effective mHealth apps. Here, we review the rationale and guidelines for the implementation of mHealth apps and the challenges regarding quality, usability, and user engagement and behavior change, with a special focus on the prevention and management of noncommunicable diseases. We suggest that a cocreation-based framework is the best method to address these challenges. Finally, we describe the current and future roles of AI in improving personalized medicine and provide recommendations for developing AI-based mHealth apps. We conclude that the implementation of AI and mHealth apps for routine clinical practice and remote health care will not be feasible until we overcome the main challenges regarding data privacy and security, quality assessment, and the reproducibility and uncertainty of AI results. Moreover, there is a lack of both standardized methods to measure the clinical outcomes of mHealth apps and techniques to encourage user engagement and behavior changes in the long term. We expect that in the near future, these obstacles will be overcome and that the ongoing European project, Watching the risk factors (WARIFA), will provide considerable advances in the implementation of AI-based mHealth apps for disease prevention and health promotion.


Assuntos
Aplicativos Móveis , Telemedicina , Humanos , Inteligência Artificial , Reprodutibilidade dos Testes , Telemedicina/métodos , Fatores de Risco
3.
Int J Mol Sci ; 23(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35955457

RESUMO

Cell-penetrating peptides (CPP) have been shown to be efficient in the transport of cargoes into the cells, namely siRNA and DNA, proteins and peptides, and in some cases, small therapeutics. These peptides have emerged as a solution to increase drug concentrations in different tissues and various cell types, therefore having a relevant therapeutic relevance which led to clinical trials. One of them, MAP, is a model amphipathic peptide with an α-helical conformation and both hydrophilic and hydrophobic residues in opposite sides of the helix. It is composed of a mixture of alanines, leucines, and lysines (KLALKLALKALKAALKLA). The CPP MAP has the ability to translocate oligonucleotides, peptides and small proteins. However, taking advantage of its unique properties, in recent years innovative concepts were developed, such as in silico studies of modelling with receptors, coupling and repurposing drugs in the central nervous system and oncology, or involving the construction of dual-drug delivery systems using nanoparticles. In addition to designs of MAP-linked vehicles and strategies to achieve highly effective yet less toxic chemotherapy, this review will be focused on unique molecular structure and how it determines its cellular activity, and also intends to address the most recent and frankly motivating issues for the future.


Assuntos
Peptídeos Penetradores de Células , Peptídeos Penetradores de Células/química , Sistemas de Liberação de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Oligonucleotídeos/metabolismo , RNA Interferente Pequeno/genética
4.
Int J Mol Sci ; 23(13)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35806112

RESUMO

Nanoparticulate systems have been widely investigated as delivery vectors for efficient drug delivery in different diseases. Nanostructured lipid carriers (NLC) are composed of both solid and liquid lipids (glyceryl dibehenate and diethylene glycol monoethyl ether) and have demonstrated enhanced biological compatibility and increased drug loading capability. Furthermore, the use of peptides, in particular cell-penetrating peptides, to functionalize nanoparticles and enhance cell membrane permeation was explored in this paper. In this paper, we described the synthesis of a new conjugated of tranylcypromine with MAP. In addition, taking into consideration our previous results, this study developed different NLCs loaded with three central nervous system (CNS) drugs (tacrine (TAC), rasagiline (RAS), and tranylcypromine (TCP)) functionalized with model amphipathic peptide (MAP) and evaluated their activity against cancer cells. Particle size analysis demonstrated NLC presented less than 200 nm and a polydispersity index less than 0.3. Moreover, in vitro results showed that conjugation of MAP with drugs led to a higher decrease in cell viability of a neuroblastoma cell line and Caco-2 cell line, more than MAP alone. Furthermore, NLC encapsulation contributed to higher cellular delivery and enhanced toxic activity at lower concentrations when compared with free or co-administration drug-MAP conjugate.


Assuntos
Peptídeos Penetradores de Células , Nanopartículas , Nanoestruturas , Células CACO-2 , Peptídeos Penetradores de Células/farmacologia , Doenças do Sistema Nervoso Central/tratamento farmacológico , Portadores de Fármacos/metabolismo , Humanos , Lipídeos , Tamanho da Partícula , Tranilcipromina
5.
Molecules ; 27(9)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35566093

RESUMO

Functionalization of nanoparticles surfaces have been widely used to improve diagnostic and therapeutic biological outcome. Several methods can be applied to modify nanoparticle surface; however, in this article we focus toward a simple and less time-consuming method. We applied an adsorption method on already formulated nanostructured lipid carriers (NLC) to functionalize these nanoparticles with three distinct peptides sequences. We selected a cell-penetrating peptide (CPP), a lysine modified model amphipathic peptide (Lys(N3)-MAP), CPP/drug complex, and the neuropeptide Y. The aim of this work is to evaluate the effect of several parameters such as peptide concentration, different types of NLC, different types of peptides, and incubation medium on the physicochemical proprieties of NLC and determine if adsorption occurs. The preliminary results from zeta potential analysis indicate some evidence that this method was successful in adsorbing three types of peptides onto NLC. Several non-covalent interactions appear to be involved in peptide adsorption with the possibility of three adsorption peptide hypothesis that may occur with NLC in solution. Moreover, and for the first time, in silico docking analysis demonstrated strong interaction between CPP MAP and NPY Y1 receptor with high score values when compared to standard antagonist and NPY.


Assuntos
Peptídeos Penetradores de Células , Nanopartículas , Portadores de Fármacos , Lipossomos , Neuropeptídeo Y
6.
Drug Dev Ind Pharm ; 47(7): 1121-1126, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34545750

RESUMO

BACKGROUND: The brief-access taste aversion (BATA) model has been used as an alternative taste assessment tool to human taste panels and became an important element of pharmaceutical drug development, especially regarding pediatric patient's compliance. This model has been validated, demonstrating a concentration-dependent sensitivity to drug aversiveness, as well as the capacity to evaluate the taste-masking effects of cyclodextrins. In the BATA model, samples are presented randomly to rodents in numerous sipper tubes and a lickometer is used for the electronic record of licks in a sophisticated approach. OBJECTIVES: The aim of this study was to test possible drug taste-masking strategies. Additionally, we have used an alternative approach to measure the animal lick number in the presence of different compounds, non-simultaneously. RESULTS: In the present work we show for the first time the licking profile of different compounds during the time course of the experiment, with each animal being exposed to only one bottle of testing product. To validate the experiments, quinine hydrochloride dihydrate (QHD) was used as a bitter reference compound. CONCLUSION: The results obtained using this simple approach showed that aversiveness is dependent on the assay duration, and that it is possible to predict the aversiveness just by measuring the mass of the tested substance consumption. Moreover, some taste-masking strategies, such as those used in pediatric formulations and corresponding to the addition of sweeteners or flavors, cannot be predicted from rodents BATA model.


Assuntos
Edulcorantes , Paladar , Animais , Criança , Composição de Medicamentos , Aromatizantes , Humanos , Quinina , Ratos
7.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360752

RESUMO

Polymeric-based nano drug delivery systems have been widely exploited to overcome protein instability during formulation. Presently, a diverse range of polymeric agents can be used, among which polysaccharides, such as chitosan (CS), hyaluronic acid (HA) and cyclodextrins (CDs), are included. Due to its unique biological and physicochemical properties, CS is one of the most used polysaccharides for development of protein delivery systems. However, CS has been described as potentially immunogenic. By envisaging a biosafe cytocompatible and haemocompatible profile, this paper reports the systematic development of a delivery system based on CS and derived with HA and CDs to nanoencapsulate the model human phenylalanine hydroxylase (hPAH) through ionotropic gelation with tripolyphosphate (TPP), while maintaining protein stability and enzyme activity. By merging the combined set of biopolymers, we were able to effectively entrap hPAH within CS nanoparticles with improvements in hPAH stability and the maintenance of functional activity, while simultaneously achieving strict control of the formulation process. Detailed characterization of the developed nanoparticulate systems showed that the lead formulations were internalized by hepatocytes (HepG2 cell line), did not reveal cell toxicity and presented a safe haemocompatible profile.


Assuntos
Quitosana , Enzimas Imobilizadas , Teste de Materiais , Nanopartículas/química , Fenilalanina Hidroxilase , Quitosana/química , Quitosana/farmacologia , Avaliação Pré-Clínica de Medicamentos , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/farmacologia , Células HEK293 , Células Hep G2 , Humanos , Fenilalanina Hidroxilase/química , Fenilalanina Hidroxilase/farmacologia
8.
Int J Mol Sci ; 22(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383645

RESUMO

Drug repurposing and drug combination are two strategies that have been widely used to overcome the traditional development of new anticancer drugs. Several FDA-approved drugs for other indications have been tested and have demonstrated beneficial anticancer effects. In this connection, our research group recently reported that Tacrine, used to treat Alzheimer's Disease, inhibits the growth of breast cancer MCF-7 cells both alone and in combination with a reference drug. In this view, we have now coupled Tacrine with the model amphipathic cell-penetrating peptide (CPP) MAP, to ascertain whether coupling of the CPP might enhance the drug's antiproliferative properties. To this end, we synthesized MAP through solid-phase peptide synthesis, coupled it with Tacrine, and made a comparative evaluation of the parent drug, peptide, and the conjugate regarding their permeability across the blood-brain barrier (BBB), ability to inhibit acetylcholinesterase (AChE) in vitro, and antiproliferative activity on cancer cells. Both MAP and its Tacrine conjugate were highly toxic to MCF-7 and SH-SY5Y cells. In turn, BBB-permeability studies were inconclusive, and conjugation to the CPP led to a considerable loss of Tacrine function as an AChE inhibitor. Nonetheless, this work reinforces the potential of repurposing Tacrine for cancer and enhances the antiproliferative activity of this drug through its conjugation to a CPP.


Assuntos
Antineoplásicos/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Tensoativos/química , Tensoativos/farmacologia , Tacrina/química , Barreira Hematoencefálica/metabolismo , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Permeabilidade
9.
AAPS PharmSciTech ; 19(4): 1625-1636, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29488195

RESUMO

Eradication of Gram-positive biofilms is a critical aspect in implant-associated infection treatment. Although antibiotic-containing particulate carriers may be a promising strategy for overcoming biofilm tolerance, the assessment of their interaction with biofilms has not been fully explored. In the present work, the antibiofilm activity of daptomycin- and vancomycin-loaded poly(methyl methacrylate) (PMMA) and PMMA-Eudragit RL 100 (EUD) microparticles against methicillin-resistant Staphylococcus aureus (MRSA) and polysaccharide intercellular adhesin-positive S. epidermidis biofilms was investigated using isothermal microcalorimetry (IMC) and fluorescence in situ hybridization (FISH). The minimal biofilm inhibitory concentrations (MBIC) of MRSA biofilms, as determined by IMC, were 5 and 20 mg/mL for daptomycin- and vancomycin-loaded PMMA microparticles, respectively. S. epidermidis biofilms were less susceptible, with a MBIC of 20 mg/mL for daptomycin-loaded PMMA microparticles. Vancomycin-loaded microparticles were ineffective. Adding EUD to the formulation caused a 4- and 16-fold reduction of the MBIC values of daptomycin-loaded microparticles for S. aureus and S. epidermidis, respectively. FISH corroborated the IMC results and provided additional insights on the antibiofilm effect of these particles. According to microscopic analysis, only daptomycin-loaded PMMA-EUD microparticles were causing a pronounced reduction in biofilm mass for both strains. Taken together, although IMC indicated that a biofilm inhibition was achieved, microscopy showed that the biofilm was not eradicated and still contained FISH-positive, presumably viable bacteria, thus indicating that combining the two techniques is essential to fully assess the effect of microparticles on staphylococcal biofilms.


Assuntos
Biofilmes/efeitos dos fármacos , Daptomicina/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Microesferas , Staphylococcus epidermidis/efeitos dos fármacos , Antibacterianos/administração & dosagem , Antibacterianos/química , Antibacterianos/metabolismo , Biofilmes/crescimento & desenvolvimento , Daptomicina/administração & dosagem , Daptomicina/metabolismo , Hibridização in Situ Fluorescente , Staphylococcus aureus Resistente à Meticilina/fisiologia , Testes de Sensibilidade Microbiana/métodos , Staphylococcus epidermidis/fisiologia
10.
Mol Pharm ; 14(9): 2977-2990, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28809501

RESUMO

Solid lipid nanoparticles (SLN) containing rifabutin (RFB), with pulmonary administration purposes, were developed through a technique that avoids the use of organic solvents or sonication. To facilitate their pulmonary delivery, the RFB-loaded SLN were included in microspheres of appropriate size using suitable excipients (mannitol and trehalose) through a spray-drying technique. Confocal analysis microscopy showed that microspheres are spherical and that SLN are efficiently microencapsulated and homogeneously distributed throughout the microsphere matrices. The aerodynamic diameters observed an optimal distribution for reaching the alveolar region. The dry powder's performance during aerosolization and the in vitro drug deposition were tested using a twin-impinger approach, which confirmed that the microspheres can reach the deep lung. Isothermal titration calorimetry revealed that SLN have higher affinity for mannitol than for trehalose. Upon microsphere dissolution in aqueous media, SLN were readily recovered, maintaining their physicochemical properties. When these dry powders reach the deep lung, microspheres are expected to readily dissolve, delivering the SLN which, in turn, will release RFB. The in vivo biodistribution of microencapsulated RFB-SLN demonstrated that the antibiotic achieved the tested organs 15 and 30 min post pulmonary administration. Their antimycobacterial activity was also evaluated in a murine model of infection with a Mycobacterium tuberculosis strain H37Rv resulting in an enhancement of activity against M. tuberculosis infection compared to nontreated animals. These results suggest that RFB-SLN microencapsulation is a promising approach for the treatment of tuberculosis.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/metabolismo , Lipídeos/química , Pulmão/metabolismo , Nanopartículas/química , Animais , Antibacterianos/uso terapêutico , Composição de Medicamentos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/patogenicidade , Nanopartículas/administração & dosagem , Rifabutina/administração & dosagem , Rifabutina/metabolismo , Rifabutina/uso terapêutico
11.
Mar Drugs ; 15(12)2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29194378

RESUMO

Pharmaceutical approaches based on nanotechnologies and the development of eye drops composed of the mucoadhesive polymers chitosan and hyaluronic acid are emerging strategies for the efficient treatment of ocular diseases. These innovative nanoparticulate systems aim to increase drugs' bioavailability at the ocular surface. For the successful development of these systems, the evaluation of mucoahesiveness (the interaction between the ocular delivery system and mucins present on the eye) is of utmost importance. In this context, the aim of the present work was to investigate the mucoadhesivity of a novel nanoparticle eye drop formulation containing an antibiotic (ceftazidime) intended to treat eye infections. Eye drop formulations comprised a polymer (hydroxypropyl) methyl cellulose (HPMC) 0.75% (w/v) in an isotonic solution incorporating chitosan/sodium tripolyphosphate (TPP)-hyaluronic acid-based nanoparticles containing ceftazidime. The viscosity of the nanoparticles, and the gels incorporating the nanoparticles were characterized in contact with mucin at different mass ratios, allowing the calculation of the rheological synergism parameter (∆η). Results showed that at different nanoparticle eye formulation:mucin weight ratios, a minimum in viscosity occurred which resulted in a negative rheological synergism. Additionally, the results highlighted the mucoadhesivity of the novel ocular formulation and its ability to interact with the ocular surface, thus increasing the drug residence time in the eye. Moreover, the in vitro release and permeation studies showed a prolonged drug release profile from the chitosan/TPP-hyaluronic acid nanoparticles gel formulation. Furthermore, the gel formulations were not cytotoxic on ARPE-19 and HEK293T cell lines, evaluated by the metabolic and membrane integrity tests. The formulation was stable and the drug active, as shown by microbiological studies. In conclusion, chitosan/TPP-hyaluronic acid nanoparticle eye drop formulations are a promising platform for ocular drug delivery with enhanced mucoadhesive properties.


Assuntos
Quitosana/química , Soluções Oftálmicas/química , Administração Oftálmica , Animais , Antibacterianos/administração & dosagem , Organismos Aquáticos , Ceftazidima/administração & dosagem , Sistemas de Liberação de Medicamentos , Células HEK293/efeitos dos fármacos , Humanos , Nanopartículas , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/farmacologia
12.
J Microencapsul ; 34(2): 203-217, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28378596

RESUMO

The aim of this study was to develop a novel BCG-loaded chitosan vaccine with high association efficiency which can afford efficient interaction with APC and elicit local and Th1-type-specific immune response after intranasal administration. Chitosan-suspended BCG and BCG-loaded chitosan-alginate microparticles were prepared by ionotropic gelation. Interaction with APC was evaluated by fluorescence microscopy using rBCG-GFP. Specific immune responses were evaluated following intranasal immunisation of mice. Cellular uptake was approximately two-fold higher for chitosan-suspended BCG. A single dose of BCG-loaded microparticles or chitosan-suspended BCG by intranasal route improved Th1-type response compared with subcutaneous BCG. Chitosan-suspended BCG originated the highest mucosal response in the lungs by intranasal route. These positive results indicate that the proposed approach of whole live BCG microencapsulation in chitosan-alginate for intranasal immunisation was successful in allowing efficient interaction with APC, while improving the cellular immune response, which is of interest for local immunisation against tuberculosis.


Assuntos
Vacina BCG/química , Quitosana/química , Macrófagos/efeitos dos fármacos , Administração Intranasal , Animais , Anticorpos Antibacterianos/sangue , Vacina BCG/administração & dosagem , Feminino , Humanos , Imunoglobulina A/análise , Imunoglobulina G/sangue , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium bovis , Células THP-1
13.
Pharm Dev Technol ; 22(2): 266-274, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27499389

RESUMO

Oral mucositis (OM) is a common adverse reaction to radiotherapy and chemotherapy in oncology. Its treatment requires oral formulations that enhance therapy compliance, improve administration and ensure drug effectiveness. Solid dosage forms that act by slow dissolution, such as pastilles, are an effective alternative to mouthwashes, for their versatility, ease of administration and extended residence time in the oral cavity. The present work describes the development and stability studies of an innovative formulation of nystatin and lidocaine pastilles for the treatment of oral mucositis. Full pharmaceutical quality testing was carried out, including disintegration and dissolution testing, texture profile analysis, grittiness and an antifungal activity testing. A soft pastille formulation containing 0.25% lidocaine and 78,000 IU nystatin was obtained, presenting suitable pharmaceutical characteristics, as a disintegration time of 17 ± 2 min, dissolution rate and microbiological and physicochemical for 30 days when stored at 2-8 °C under light protection. Palatability was also evaluated, being well accepted by a panel of 38 healthy volunteers. This formulation allows an accurate drug dosing by the prescriber, while enabling the patients to control the retention time of the drugs in the oral cavity and consequently manage their pain treatment.


Assuntos
Antifúngicos/administração & dosagem , Candida albicans/efeitos dos fármacos , Candidíase Bucal/tratamento farmacológico , Lidocaína/administração & dosagem , Nistatina/administração & dosagem , Estomatite/tratamento farmacológico , Antifúngicos/química , Antifúngicos/farmacologia , Liberação Controlada de Fármacos , Dureza , Humanos , Lidocaína/química , Lidocaína/farmacologia , Nistatina/química , Nistatina/farmacologia , Comprimidos
14.
Nanomedicine ; 12(1): 143-61, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26410277

RESUMO

During the past decade, the number of studies describing nanostructured lipid carriers (NLCs)-based formulations has been dramatically increased. The raise in NLC exploitation is essentially due to defeated barriers within the technological process of lipid-based nanoparticles' formulation and increased knowledge of the underlying mechanisms of transport of NLCs via different routes of administration. This review article aims to give an overview on the current state of the art of NLC as controlled drug delivery systems for future clinics through novel NLC applications providing examples of successfull outcomes. The reported data clearly illustrate the promise of these nanoparticles for novel treatments in the near future. From the Clinical Editor: The understanding of the nanostructured lipid carriers (NLC)-based formulations has improved with continuing research recently. The result has seen an increase in the use of these in the clinical setting. In this comprehensive review, the authors discussed the current state and major challenges in the use of nanostructured lipid carriers as controlled drug delivery systems.


Assuntos
Previsões , Lipídeos/química , Lipossomos/química , Nanocápsulas/química , Nanocápsulas/ultraestrutura , Nanomedicina/tendências , Difusão
15.
Mar Drugs ; 14(5)2016 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-27187418

RESUMO

The aim of the present study was to develop novel Mycobacterium bovis bacille Calmette-Guérin (BCG)-loaded polymeric microparticles with optimized particle surface characteristics and biocompatibility, so that whole live attenuated bacteria could be further used for pre-exposure vaccination against Mycobacterium tuberculosis by the intranasal route. BCG was encapsulated in chitosan and alginate microparticles through three different polyionic complexation methods by high speed stirring. For comparison purposes, similar formulations were prepared with high shear homogenization and sonication. Additional optimization studies were conducted with polymers of different quality specifications in a wide range of pH values, and with three different cryoprotectors. Particle morphology, size distribution, encapsulation efficiency, surface charge, physicochemical properties and biocompatibility were assessed. Particles exhibited a micrometer size and a spherical morphology. Chitosan addition to BCG shifted the bacilli surface charge from negative zeta potential values to strongly positive ones. Chitosan of low molecular weight produced particle suspensions of lower size distribution and higher stability, allowing efficient BCG encapsulation and biocompatibility. Particle formulation consistency was improved when the availability of functional groups from alginate and chitosan was close to stoichiometric proportion. Thus, the herein described microparticulate system constitutes a promising strategy to deliver BCG vaccine by the intranasal route.


Assuntos
Alginatos/química , Vacina BCG/química , Quitosana/química , Mycobacterium bovis/química , Nanopartículas/química , Administração Intranasal , Animais , Vacina BCG/imunologia , Materiais Biocompatíveis/química , Células Cultivadas , Química Farmacêutica/métodos , Portadores de Fármacos/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Mycobacterium tuberculosis/imunologia , Tamanho da Partícula , Polímeros/química
16.
Pharm Res ; 31(11): 3136-49, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24842662

RESUMO

PURPOSE: To prepare and thoroughly characterize a new polymorph of the broad-spectrum antibiotic minocycline from its hydrochloride dehydrate salts. METHODS: The new minocycline hydrochloride polymorph was prepared by means of the antisolvent effect caused by carbon dioxide. Minocycline recrystallized as a red crystalline hydrochloride salt, starting from solutions or suspensions containing CO2 and ethanol under defined conditions of temperature, pressure and composition. RESULTS: This novel polymorph (ß-minocycline) revealed characteristic PXRD and FTIR patterns and a high melting point (of 247 ºC) compared to the initial minocycline hydrochloride hydrates (α-minocycline). Upon dissolution the new polymorph showed full anti-microbial activity. Solid-state NMR and DSC studies evidenced the higher chemical stability and crystalline homogeneity of ß-minocycline compared to the commercial chlorohydrate powders. Molecular structures of both minocyclines present relevant differences as shown by multinuclear solid-state NMR. CONCLUSIONS: This work describes a new crystalline structure of minocycline and evidences the ability of ethanol-CO2 system in removing water molecules from the crystalline structure of this API, at modest pressure, temperature and relatively short time (2 h), while controlling the crystal habit. This process has therefore the potential to become a consistent alternative towards the control of the solid form of APIs.


Assuntos
Dióxido de Carbono/química , Minociclina/química , Polímeros/química , Anti-Infecciosos/química , Cristalização/métodos , Etanol/química , Pós/química , Solubilidade , Soluções/química , Suspensões/química , Temperatura , Água/química
17.
Exp Parasitol ; 135(1): 166-74, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23830988

RESUMO

Malaria cysteine proteases have been shown to be immunogenic and are being exploited as serodiagnostic markers, drug and vaccine targets. Several Plasmodium spp. cysteine proteases have been described and the best characterized of these are the falcipains, a family of papain-family enzymes. Falcipain-2 and falcipain-3 act in concert with other proteases to hydrolyze host erythrocyte hemoglobin in the parasite food vacuole. Falcipain-1 has less similarity to the other falcipains and its physiological role in parasite asexual blood stage still remains uncertain. Immunolocalization studies using an antibody developed against the Plasmodium chabaudi recombinant chabaupain-1, the falcipain-1 ortholog, were performed confirming its cellular localization in both erythrocyte and mosquito ookinete stage. Immunostaining of chabaupain-1 preferentially in apical portion of parasite ookinete suggests that this protease may be related with parasite egression from mosquito midgut. Immune responses to chabaupain-1 were evaluated using two different adjuvants, chitosan nanoparticles and hydroxide aluminum. Mice immunized with the recombinant protein alone or in association with nanoparticles were challenged with P. chabaudi showing that immunization with the recombinant protein confers partial protection to blood stage infection in BALB/c animal model.


Assuntos
Anticorpos Antiprotozoários/biossíntese , Cisteína Proteases/imunologia , Vacinas Antimaláricas , Malária/prevenção & controle , Plasmodium chabaudi/enzimologia , Plasmodium chabaudi/imunologia , Animais , Anopheles/parasitologia , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Anticorpos Antiprotozoários/imunologia , Cisteína Proteases/análise , Cisteína Proteases/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Eritrócitos/parasitologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Plasmodium berghei/fisiologia , Plasmodium chabaudi/crescimento & desenvolvimento , Proteínas Recombinantes/análise , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Vacinas Sintéticas
18.
Drug Deliv Transl Res ; 13(12): 3030-3058, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37294425

RESUMO

Microencapsulation of the therapeutical monoclonal antibody infliximab (INF) was investigated as an innovative approach to improve its stability and to achieve formulations with convenient features for intra-articular administration. Ultrasonic atomization (UA), a novel alternative to microencapsulate labile drugs, was compared with the conventional emulsion/evaporation method (Em/Ev) using biodegradable polymers, specifically Polyactive® 1000PEOT70PBT30 [poly(ethylene-oxide-terephthalate)/poly(butylene-terephthalate); PEOT-PBT] and its polymeric blends with poly-(D, L-lactide-co-glycolide) (PLGA) RG502 and RG503 (PEOT-PBT:PLGA; 65:35). Six different formulations of spherical core-shell microcapsules were successfully developed and characterized. The UA method achieved a significantly higher encapsulation efficiency (69.7-80.25%) than Em/Ev (17.3-23.0%). Mean particle size, strongly determined by the microencapsulation method and to a lesser extent by polymeric composition, ranged from 26.6 to 49.9 µm for UA and 1.5-2.1 µm for Em/Ev. All formulations demonstrated sustained INF release in vitro for up to 24 days, with release rates modulated by polymeric composition and microencapsulation technique. Both methods preserved INF biological activity, with microencapsulated INF showing higher efficacy than commercial formulations at comparable doses regarding bioactive tumor necrosis factor-alpha (TNF-α) neutralization according to WEHI-13VAR bioassay. Microparticles' biocompatibility and extensive internalization by THP-1-derived macrophages was demonstrated. Furthermore, high in vitro anti-inflammatory activity was achieved after treatment of THP-1 cells with INF-loaded microcapsules, significatively reducing in vitro production of TNF-α and interleucine-6 (Il-6).


Assuntos
Artrite Reumatoide , Produtos Biológicos , Humanos , Infliximab , Fator de Necrose Tumoral alfa , Cápsulas , Polímeros , Artrite Reumatoide/tratamento farmacológico , Tamanho da Partícula , Microesferas
19.
Life Sci ; 329: 121838, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37290668

RESUMO

There has been an increased interest of the scientific community in cannabis and its constituents for therapeutic purposes. Although it is believed that cannabinoids can be effective for a few different conditions and syndromes, there are little objective data that clearly support the use of cannabis, cannabis extracts or even cannabidiol (CBD) oil. This review aims to explore the therapeutic potential of phytocannabinoids and synthetic cannabinoids for the treatment of several diseases. A broad search covering the past five years, was performed in PubMed and ClinicalTrial.gov databases, to identify papers focusing on the use of medical phytocannabinoids in terms of tolerability, efficacy and safety. Accordingly, there are preclinical data supporting the use of phytocannabinoids and synthetic cannabinoids for the management of neurological pathologies, acute and chronical pain, cancer, psychiatric disorders and chemotherapy-induced emetic symptoms. However, regarding the clinical trials, most of the collected data do not fully support the use of cannabinoids in the treatment of such conditions. Consequently, more studies are still needed to clarify ascertain if the use of these compounds is useful in the management of different pathologies.


Assuntos
Canabidiol , Canabinoides , Cannabis , Neoplasias , Humanos , Canabinoides/farmacologia , Canabinoides/uso terapêutico , Agonistas de Receptores de Canabinoides , Neoplasias/tratamento farmacológico , Canabidiol/farmacologia , Canabidiol/uso terapêutico
20.
Eur J Pharm Biopharm ; 187: 1-11, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37011788

RESUMO

The structural maintenance of therapeutic proteins during formulation and/or storage is a critical aspect, particularly for multi-domain and/or multimeric proteins which usually exhibit intrinsic structural dynamics leading to aggregation with concomitant loss-of-function. Protein freeze-drying is a widely used technique to preserve protein structure and function during storage. To minimize chemical/physical stresses occurring during this process, protein stabilizers are usually included, their effect being strongly dependent on the target protein. Therefore, they should be screened for on a time-consuming case-by-case basis. Herein, differential scanning fluorimetry (DSF) and isothermal denaturation fluorimetry (ITDF) were employed to screen, among different classes of freeze-drying additives, for the most effective stabilizer of the model protein human phenylalanine hydroxylase (hPAH). Correlation studies among retrieved DSF and ITDF parameters with recovered enzyme amount and activity indicated ITDF as the most appropriate screening method. Biochemical and biophysical characterization of hPAH freeze-dried with ITDF-selected stabilizers and a long-term storage study (12 months, 5 ± 3 °C) showed that the selected compounds prevented protein aggregation and preserved hPAH structural and functional properties throughout time storage. Our results provide a solid basis towards the choice of ITDF as a high-throughput screening step for the identification of protein freeze-drying protectors.


Assuntos
Fenilalanina Hidroxilase , Humanos , Proteínas/química , Liofilização/métodos , Fluorometria , Excipientes/química , Desnaturação Proteica
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