RESUMO
La enfermedad de Chagas es una enfermedad parasitaria (Trypanosoma cruzi), endémica en 21 países de América y que las migraciones la han dispersado en distintos continentes. Una de las manifestaciones más precoces de esta enfermedad son las alteraciones disautonómicas o disfunción autonómica. La severidad de este inadecuado funcionamiento del sistema nervioso autónomo resulta mensurable, de modo que la evolución y/o progresión de la enfermedad puede constatarse mediante la alteración de estudios clínicos y detección de anticuerpos antimuscarínicos. Estos anticuerpos están presentes en un 30% de los infectados y aparecen muy precozmente una vez instalada la parasitosis; además otros estudios, como la dispersión del QT (>65 mseg) y la variabilidad de la frecuencia cardíaca (<100 mseg) presentan valores anormales. La utilización de nuevos paradigmas de atención, diagnóstico y tratamientos adecuados son imprescindibles para prevenir el desarrollo de esta cardiopatía.
Chagas disease is a parasitic disease (Trypanosoma cruzi), endemic in 21 countries of America and that migrations have dispersed it in different continents. One of the earliest manifestations of this disease is dysautonomic alterations or autonomic dysfunction. The severity of this inadequate functioning of the autonomic nervous system is measurable, so that the evolution and/or progression of the disease can be verified by altering clinical studies and detecting antimuscarinic antibodies. These antibodies are present in 30% of those infected and appear very early once the parasitosis is installed; In addition, other studies, such as QT dispersion (> 65 ms) and heart rate variability (<100 ms) show abnormal values. The use of new paradigms of care, diagnosis and appropriate treatments are essential to prevent the development of this heart disease.
A doença de Chagas é uma doença parasitária (Trypanosoma cruzi), endêmica em 21 países da América e que as migrações a dispersaram em diferentes continentes. Uma das primeiras manifestações desta doença são as alterações disautonômicas ou disfunção autonômica. A gravidade desse funcionamento inadequado do sistema nervoso autônomo é mensurável, de modo que a evolução e/ou progressão da doença pode ser verificada alterando os estudos clínicos e detectando anticorpos antimuscarínicos. Esses anticorpos estão presentes em 30% dos infectados e aparecem muito cedo, uma vez instalada a parasitose; Além disso, outros estudos, como a dispersão do QT (> 65 mseg) e a variabilidade da freqüência cardíaca (<100 mseg), mostram valores anormais. A utilização de novos paradigmas de atendimento, diagnóstico e tratamentos adequados são essenciais para prevenir o desenvolvimento desta doença cardíaca.
RESUMO
Leishmaniasis is a Neglected Tropical Diseases caused by protozoan parasites of the genus Leishmania. It is a major health problem in many tropical and subtropical regions of the world and can produce three different clinical manifestations, among which cutaneous leishmaniasis has a higher incidence in the world than the other clinical forms. There are no recognized and reliable means of chemoprophylaxis or vaccination against infections with different forms of leishmaniasis. In addition, chemotherapy, unfortunately, remains, in many respects, unsatisfactory. Therefore, there is a continuing and urgent need for new therapies against leishmaniasis that are safe and effective in inducing a long-term cure. This review summarizes the latest advances in currently available treatments and improvements in the development of drug administration. In addition, an analysis of the in vivo assays was performed and the challenges facing promising strategies to treat CL are discussed. The treatment of leishmaniasis will most likely evolve into an approach that uses multiple therapies simultaneously to reduce the possibility of developing drug resistance. There is a continuous effort to discover new drugs to improve the treatment of leishmaniasis, but this is mainly at the level of individual researchers. Undoubtedly, more funding is needed in this area, as well as greater participation of the pharmaceutical industry to focus efforts on the development of chemotherapeutic agents and vaccines for this and other neglected tropical diseases.
Assuntos
Leishmania , Leishmaniose Cutânea , Vacinas , Humanos , Leishmaniose , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/prevenção & controle , Doenças Negligenciadas , Preparações FarmacêuticasRESUMO
Background: Leishmaniasis is a neglected tropical disease and its cutaneous form manifests as ulcers or nodules, generally in exposed parts of the body. This work aimed to develop ivermectin (IVM) thermosensitive hydrogels as topical formulations to improve cutaneous leishmaniasis treatment. Materials & methods: Hydrogels based on poloxamers 407 and 188 with different concentrations of IVM were prepared and rheologically characterized. The IVM release profiles were obtained and mathematically analyzed using the Lumped model. Results: The formulation containing 1.5% w/w of IVM presented an adequate gelling temperature, an optimal complex viscosity and elastic modulus. Hydrogels allowed to modulate the release of IVM. Conclusion: IVM thermosensitive hydrogels can be considered a valuable alternative to improve the treatment of cutaneous leishmaniasis.
Assuntos
Ivermectina , Leishmaniose Cutânea , Preparações de Ação Retardada , Humanos , Hidrogéis , Leishmaniose Cutânea/tratamento farmacológico , PoloxâmeroRESUMO
Controlled drug delivery aims to achieve an effective drug concentration in the action site for a desired period of time, while minimizing side effects. In this contribution, biodegradable poly(3-hydroxybutyrate) films were evaluated as a reservoir platform for dexamethasone controlled release. These systems were morphological and physicochemically characterized. In vitro release assays were performed for five different percentages of drug in the films and data were fitted by a mathematical model developed and validated by our research group. When the profiles were normalized, a single curve properly fitted all the experimental data. Using this unique curve, the dissolution efficiency (DE), the time to release a given amount of drug (tX% ), and the mean dissolution time were calculated. Furthermore, the dissolution rate, the initial dissolution rate (a%) and the intrinsic dissolution rate were determined. The a% mean value was 1.968â¯×â¯10-2% released/min, t80% was about 14â¯days, and the DE was 59.6% at 14â¯days and 66.5% at 20â¯days. After 2â¯days, when approximately 40% of the drug was released, the dissolution rate decreased about 60% respect to the initial value. The poly(3-hydroxybutyrate) platforms behaved as an appropriate system to release and control the dexamethasone delivery, suggesting that they could be an alternative to improve drug therapy.
RESUMO
Mathematical modeling in drug release systems is fundamental in development and optimization of these systems, since it allows to predict drug release rates and to elucidate the physical transport mechanisms involved. In this paper we validate a novel mathematical model that describes progesterone (Prg) controlled release from poly-3-hydroxybutyric acid (PHB) membranes. A statistical analysis was conducted to compare the fitting of our model with six different models and the Akaike information criterion (AIC) was used to find the equation with best-fit. A simple relation between mass and drug released rate was found, which allows predicting the effect of Prg loads on the release behavior. Our proposed model was the one with minimum AIC value, and therefore it was the one that statistically fitted better the experimental data obtained for all the Prg loads tested. Furthermore, the initial release rate was calculated and therefore, the interface mass transfer coefficient estimated and the equilibrium distribution constant of Prg between the PHB and the release medium was also determined. The results lead us to conclude that our proposed model is the one which best fits the experimental data and can be successfully used to describe Prg drug release in PHB membranes.
RESUMO
El siguiente artículo versa sobre la problemática de las pérdidas y desperdicios de alimentos y su relación con la seguridad alimentaria, el cuidado del ambiente y los recursos. Se describe un estado del arte mundial, regional y nacional, a la vez que se enuncian las principales definiciones acordadas a nivel internacional. Asimismo, se expresan los avances en América Latina y el Caribe, y en especial en Argentina por medio del Programa Nacional de Reducción de Pérdida y Desperdicio de Alimentos que lleva adelante el Ministerio de Agroindustria de la Nación. El objetivo de la nota es despertar el interés de los lectores frente a la oportunidad de propiciar sistemas agroalimentarios más eficientes, sostenibles, e inclusivos; que se traduzcan en una producción de excelente calidad, y que impulsen el consumo de alimentos responsable. Perder y desperdiciar alimentos significa un costo ambiental, un costo económico y por sobre todo un costo ético. Finalmente se proponen soluciones y posibles líneas de acción de forma tal que los profesionales de la salud, la nutrición y los alimentos; así como otros colegas, puedan contribuir a aprovechar mejor los alimentos...
Assuntos
Argentina , Alimentos , Perda e Desperdício de Alimentos , Ecologia da NutriçãoRESUMO
Poly(3-hydroxybutyrate) (PHB) biodegradable polymeric membranes were evaluated as platform for progesterone (Prg)-controlled release. In the design of new drug delivery systems, it is important to understand the mass transport mechanism involved, as well as predict the process kinetics. Drug release experiments were conducted and the experimental results were evaluated using engineering approaches that were extrapolated to the pharmaceutical field by our research group. Membranes were loaded with different Prg concentrations and characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). SEM images showed that membranes have a dense structure before and after the progesterone addition. DSC and FTIR allowed determining the influence of the therapeutic agent in the membrane properties. The in vitro experiments were performed using two different techniques: (A) returning the sample to the receptor solution (constant volume of the delivery medium) and (B) extracting total volume of the receptor solution. In this work, we present a simple and accurate "lumped" second-order kinetic model. This lumped model considers the different mass transport steps involved in drug release systems. The model fits very well the experimental data using any of the two experimental procedures, in the range 0 ≤ t ≤ ∞ or 0 ≤ M t ≤ M ∞. The drug release analysis using our proposed approaches is relevant for establishing in vitro-in vivo correlations in future tests in animals.