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In recent years, research has been conducted in search of alternative adhesives that are less harmful to human health and the environment. Cardanol derived from cashew nut shell liquid (CNSL) has attracted considerable attention due to its chemical and specific characteristics (antioxidant activity, flame resistance, and hydrophobicity). In this sense, this study aimed to evaluate the quality of particleboards using cardanol instead of urea-formaldehyde (UF) adhesive. Different percentages of cardanol were used (0, 20, 40, 60 and 80%) in which its physicochemical properties were evaluated. The panels were produced with particles of Pinus oocarpa and nominal density of 0.75 g/cm3, their physical and mechanical properties were evaluated, wood-adhesive interface evaluation with scanning electron microscopy (SEM), and the combustibility test. It is concluded that the maximum replacement of UF by cardanol is 5%, since, in this situation, the mentioned properties reach the established norms for the commercialization of the boards.

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Polyploidy is a phenomenon that alters the genetic diversity of populations and has been reported as one of the most important evolutionary forces for plant diversification. The Psidium cattleyanum complex comprises a group of wild populations with several ploidy levels reported in the literature. The multiple cytotypes, associated with its wide distribution area, make this species a potential key model for understanding evolutionary processes related to polyploidization. In this study, we isolated and characterized nuclear microsatellite markers of P. cattleyanum and tested their transferability to other nine species of the genus. We performed a preliminary analysis of genetic diversity and population structure in three populations of P. cattleyanum. The three populations analyzed had different chromosome numbers, being polyploid cytotypes (2n = 6x = 66, 2n = 7x = 77 and 2n = 8x = 88). We designed 46 primer pairs and successfully amplified 37 markers, from which the 10 best were selected for analysis. Considering both the PIC and DP values, most of markers were highly informative. The new SSR markers were used to assess the levels of genetic diversity of the populations and detected one population with predominance of sexual reproduction. DAPC analysis pointed the formation of three groups, which corresponded to the populations analyzed. The markers were successfully amplified in related species, with some species presenting 80% transferability. By producing this panel of polymorphic microsatellites, we contribute to the understanding evolution in groups of natural polyploids for future studies.

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BACKGROUND: Malaria is still a dangerous disease that impacts specifically Africa, Asia, and Latin America. The development of therapies to overcome the parasite infection is an important challenge nowadays. The medicine primaquine (PQ) is used in the treatment, although several side effects and low oral bioavailability are reported. OBJECTIVE: This work focused on the preparation and characterization of a complex between PQ and 2- hydroxypropyl-ß-cyclodextrin (HPCD), besides performing release tests of this formulation. METHODS: PQ:HPCD complexes were prepared at 1:1 and 1:2 molar ratios, by the lyophilization method. The association between PQ and HPCD was tested using UV-vis, infrared (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy and NMR techniques (chemical shift, Job Plot, DOSY, and ROESY). Tests were also conducted to evaluate drug release before and after complexation with HPCD. RESULTS: Results showed that there was a weak interaction of PQ with HPCD, forming non-inclusion complexes. These results were supported by FTIR results and spatial correlations between hydrogens from PQ with the external HPCD hydrogens. A 1:2 PQ:HPCD preferred molar ratio was determined by DSC and Job Plot experiments and the time to release 96% of the drug was 21.2 h slower after complexation. CONCLUSION: Conclusion indicate that PQ interacts poorly with HPCD, probably due to its hydrophilic character, as well as to its interaction with the external rim of HPCD. Our results demonstrate that there was a significant improvement in the release time after the complexation process, which could lead to an increase in the activity of the drug.

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Work is one of the main orienters of mental life, making it relevant to investigate the relationship between mental disorders, especially alcohol use, and job satisfaction. OBJECTIVE: To carry out a systematic review of scientific articles on job satisfaction and alcohol use. METHOD: Articles were searched in the databases MEDLINE (PubMed), Web of Science, and Scopus, in the English, Spanish and Portuguese languages. The review was based on the PRISMA criteria, from 2008 to 2017. RESULTS: Evidence of a moderate positive correlation was found in cross-cutting, but that changes over time, and that the relationship between job satisfaction and use of alcohol is moderated by burnout, working conditions, job demand and control, relationship with the leader, social support and work climate. CONCLUSION: The results reaffirm the need to explore the theme to design intervention strategies in the context of work.

O trabalho é um dos principais orientadores da vida mental, tornando-se relevante investigar a relação entre transtornos mentais, sobretudo o uso de álcool, e satisfação no trabalho. OBJETIVO: Realizar revisão sistemática de artigos científicos sobre a satisfação no trabalho e o uso de álcool. MÉTODO: Foram pesquisados artigos nos bancos de dados MEDLINE (PubMed), Web of Science e Scopus, nas línguas inglesa, espanhola e portuguesa. A revisão embasou-se nos critérios do PRISMA, no período de 2008 a 2017. RESULTADOS: Encontraram-se evidências de correlação positiva moderada em recortes transversais, mas que se modificam ao longo do tempo, e constatou-se que a relação entre satisfação no trabalho e uso de álcool é moderada por burnout, condições de trabalho, demanda e controle do trabalho, relacionamento com o líder, suporte social e clima de trabalho. CONCLUSÃO: Os resultados reafirmam a necessidade de explorar o tema para traçar estratégias de intervenção no contexto do trabalho.

Los factores que pueden influir en la satisfacción en el trabajo están presentes de diferentes formas y con repercusiones diversas. OBJETIVO: Realizar una revisión sistemática de artículos científicos sobre la satisfacción en el trabajo y el uso de alcohol en el período de 2008 a 2017. MÉTODO: Los artículos fueron investigados bases MEDLINE (PubMed), Web of Science y Scopus, en las lenguas inglesa, espanola y portuguesa. La La revisión se basó en los criterios del PRISMA. RESULTADOS: se encontraron evidencias de correlación positiva moderada en recortes transversales, pero que modifican a lo largo del tiempo, y que la relación entre satisfacción en el trabajo y uso de alcohol es moderada por burnout, condiciones de trabajo, demanda y control, relación con el líder, el apoyo social y el clima de trabajo. CONCLUSIÓN: Los resultados reafirmamos la necesidad de explorar el tema para trazar estrategias de intervención en el contexto del trabajo.

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The inclusion complexes between 17-α-methyltestosterone (MT) and ß-cyclodextrin (bCD) were prepared and characterized in dissolution and solid phase. The complex promoted a sixfold increment in solubility of the hormone. It has a limited solubility and stoichiometry of 2:1 (bCD:MT) determined by DSC, NMR and solubility experiments, the association constant Ka=2846Lmol-1 and complex fraction of 76% (assessed by DOSY-NMR, in (1:3) DMSO/D2O). The association constant obtained in water by the solubility isotherms is 7540Lmol-1. 2D-ROESY experiments indicate the intermolecular orientation (complete inclusion of the hormone in the cavity). Simulations by molecular dynamics agreed with the formation of the inclusion complex 2:1. Release tests showed the slower release for the complexes, with 50% for lyophilization and 56% for malaxation. These results clearly demonstrate the complexation of MT in bCD, which formulations are promising for further applications involving this steroid in aquaculture, both for sexual reversal and in technologies of hormone in water sequestration.

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El humor, cuerpo o fluido vítreo (HV) es un gel claro que ocupa la cavidad vítrea o cavidad posterior del globo ocular y cuyas funciones son las de dar volumen al ojo, sostener la retina y mantener su transparencia de manera que los haces de luz puedan atravesarla. En este estudio se aborda la importancia del humor vítreo como muestra en el área de la bioquímica clínica, y se destaca su valor en el ámbito de las ciencias forenses. El humor vítreo es una muestra indispensable en la investigación de casos de muertes sospechosas, inexplicables o violentas, puesto que su ubicación proporciona un medio estéril para determinaciones como la confirmación post mortem de la ingestión de etanol. Tiene un rol en la determinación de drogas, intervalo post mortem, diabetes, deshidratación, desnutrición e insuficiencia renal. La interpretación de los datos puede ser problemática donde factores como la difusión post mortem de las drogas desde el cerebro hacia la cavidad vítrea, el método analítico, la recolección de la muestra, la calibración y el tratamiento estadístico de los datos aportan dificultad en la interpretación y añaden más variables a la hipótesis de investigación. La investigación del humor vítreo como matriz de análisis tiene una importancia considerable y debería ser difundida en países como Brasil y otros de América Latina donde, a pesar de existir personal capacitado para trabajar con esta muestra, este tipo de análisis no se pone en práctica con la debida frecuencia.

The vitreous humor, body or fluid is the clear gel that fills the vitreous chamber or posterior chamber of the eyeball, whose functions are to give volume to the eye, serve as retina support and maintain its transparency to allow light beams to reach the retina. This study addresses the vitreous humor as an important sample for clinical biochemistry, pointing out its value for forensic sciences. The vitreous humor is a mandatory sample in cases of suspected, unexplained or violent deaths and its location gives a sterile medium for the postmortem confirmation of alcohol intake. It plays a role in the measurement of drugs, estimation of postmortem interval, and definition of diabetes, dehydration and renal failure. Factors such as drug postmortem diffusion in the vitreous humour coming from the brain, along with factors of the analytical method such asthe collection process, calibration and statistical processing of data, make it difficult to interpret and add more variables to the cases investigated. HV use should be promoted in countries like Brazil and in Latin America, which possess trained professionals to address and use this biological sample, but who do not work with it frequently.

O humor, corpo ou fluido vítreo (HV) é um gel claro que enche a cavidade vítrea ou cavidade posterior do globo ocular, cujas funções são dar volume ao olho, apoiar a retina e manter a sua transparência para permitir que os feixes de luz possam atravessá-la. Este trabalho aborda a importância do humor vítreo como amostra na área da bioquímica clínica, destacando seu valor no âmbito das ciências forenses. O humor vítreo é amostra obrigatória na investigação de casos de mortes suspeitas, inexplicáveis ou violentas, visto que sua localização provê um meio estéril para, por exemplo, determinações como a confirmação post mortem da ingestão de etanol. Tem um papel na mensuração de drogas, estimação do intervalo post mortem, diabetes, desidratação, desnutrição e insuficiência renal. Fatores como a difusão post mortem das drogas desde o cérebro para a cavidade vítrea, juntamente com o método analítico, o processo de coleta da amostra, calibração e tratamento estatístico dos dados, trazem dificuldades na interpretação e adicionam mais variáveis às hipóteses de investigação. A investigação do humor vítreo como matriz de análise tem importância considerável e deveria ser divulgada em países como o Brasil e outros da América Latina onde, apesar de contar com profissionais capacitados para trabalhar com esta amostra, ainda não colocam em prática esta análise com a merecida frequência.

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A atemoia é um fruto híbrido derivado do cruzamento entre a fruta-do-conde, mais conhecida como ata (Annona squamosa L.), com a cherimoia (Annona cherimola Mill.). Este trabalho foi realizado com o objetivo de caracterizar os constituintes químicos das frações casca, polpa e semente de atemoia Gefner. Os frutos adquiridos foram selecionados, pesados e medidos. Foram separados em casca, polpa, semente e eixo floral, que também foram pesados para determinar suas proporções. Para o restante dos frutos, foram separadas as frações em sete repetições de 13 frutos. Em seguida, as frações casca, polpa e sementes foram liofilizadas e armazenadas em freezer. Foi determinada a proporção das frações do fruto, a composição centesimal, o ácido ascórbico, os açúcares totais, os minerais e alguns compostos bioativos. A polpa representou cerca de 60% do peso do fruto, enquanto a casca 28,13% e as sementes 8,34%. O fruto apresentou, em média, 56 sementes, com diâmetro longitudinal de 10,79cm e diâmetro transversal de 26,64cm. Os maiores teores de proteína bruta, extrato etéreo e fibra alimentar foram encontrados nas sementes e casca. A casca se destacou nos teores de cinzas. A polpa apresentou os maiores teores de ácido ascórbico e açúcares totais em relação às outras frações. A ordem da composição de macronutrientes na casca, na polpa e nas sementes da atemoia foi K>P>Ca>Mg; para os micronutrientes na casca e nas sementes, foi Fe>Zn>Cu>Mn>S e, na polpa, foi Fe>Zn>Mn>Cu>S. A casca apresentou os níveis mais altos de inibidores de tripsina e atividade hemaglutinante. Os teores de compostos fenólicos foram relativamente baixos no fruto.

The atemoya is a hybrid fruit derived from the cross between the sugar apple (fruta-do-conde), better known as ata (Annona squamosa L.) with the cherimoya (Annona cherimola Mill.). The aim of this research was to characterize the chemical constituents of the fractions skin, pulp and seed of the hybrid fruit atemoya, variety Gefner. The fruits purchased and selected were weighed and measured. They were separated into skin, pulp, seed and floral axis which were also weighted to determine their proportions. For the rest of the fruits, the fractions were separated into 7 replicates of 13 fruits. Then, the fractions skin, pulp and seeds were freeze-dried and stored in freezer. The proportion of the fruit fractions, the centesimal composition, ascorbic acid, total sugars, minerals and some bioactive compounds were determined. The pulp represented about 60% of the fruit weight, while the skin 28.13% and the seeds 8.34%. The fruit presented on the average 56 seeds, with longitudinal diameter of 10.79 cm and transversal diameter of 26.64 cm. The largest contents of crude protein, ether extract and dietary fiber were found in both seeds and skin. The skin stood out in the ash contents. The pulp showed the highest contents of ascorbic acid and total sugars in relation to the other fractions. The order of the composition of macronutrients in the skin, pulp and seeds of the atemoya was K>P>Ca>Mg; for the skin and seed micronutrients were Fe>Zn>Cu>Mn>S and in the pulp were Fe>Zn>Mn>Cu>S. The skin presented the highest levels of trypsin inhibitors and hemagglutinating activity. The phenolic compounds were relatively low in the fruit.

RESUMEN

The atemoya is a hybrid fruit derived from the cross between the sugar apple (fruta-do-conde), better known as ata (Annona squamosa L.) with the cherimoya (Annona cherimola Mill.). The aim of this research was to characterize the chemical constituents of the fractions skin, pulp and seed of the hybrid fruit atemoya, variety Gefner. The fruits purchased and selected were weighed and measured. They were separated into skin, pulp, seed and floral axis which were also weighted to determine their proportions. For the rest of the fruits, the fractions were separated into 7 replicates of 13 fruits. Then, the fractions skin, pulp and seeds were freeze-dried and stored in freezer. The proportion of the fruit fractions, the centesimal composition, ascorbic acid, total sugars, minerals and some bioactive compounds were determined. The pulp represented about 60% of the fruit weight, while the skin 28.13% and the seeds 8.34%. The fruit presented on the average 56 seeds, with longitudinal diameter of 10.79 cm and transversal diameter of 26.64 cm. The largest contents of crude protein, ether extract and dietary fiber were found in both seeds and skin. The skin stood out in the ash contents. The pulp showed the highest contents of ascorbic acid and total sugars in relation to the other fractions. The order of the composition of macronutrients in the skin, pulp and seeds of the atemoya was K>P>Ca>Mg; for the skin and seed micronutrients were Fe>Zn>Cu>Mn>S and in the pulp were Fe>Zn>Mn>Cu>S. The skin presented the highest levels of trypsin inhibitors and hemagglutinating activity. The phenolic compounds were relatively low in the fruit.

A atemoia é um fruto híbrido derivado do cruzamento entre a fruta-do-conde, mais conhecida como ata (Annona squamosa L.), com a cherimoia (Annona cherimola Mill.). Este trabalho foi realizado com o objetivo de caracterizar os constituintes químicos das frações casca, polpa e semente de atemoia Gefner. Os frutos adquiridos foram selecionados, pesados e medidos. Foram separados em casca, polpa, semente e eixo floral, que também foram pesados para determinar suas proporções. Para o restante dos frutos, foram separadas as frações em sete repetições de 13 frutos. Em seguida, as frações casca, polpa e sementes foram liofilizadas e armazenadas em freezer. Foi determinada a proporção das frações do fruto, a composição centesimal, o ácido ascórbico, os açúcares totais, os minerais e alguns compostos bioativos. A polpa representou cerca de 60% do peso do fruto, enquanto a casca 28,13% e as sementes 8,34%. O fruto apresentou, em média, 56 sementes, com diâmetro longitudinal de 10,79cm e diâmetro transversal de 26,64cm. Os maiores teores de proteína bruta, extrato etéreo e fibra alimentar foram encontrados nas sementes e casca. A casca se destacou nos teores de cinzas. A polpa apresentou os maiores teores de ácido ascórbico e açúcares totais em relação às outras frações. A ordem da composição de macronutrientes na casca, na polpa e nas sementes da atemoia foi K>P>Ca>Mg; para os micronutrientes na casca e nas sementes, foi Fe>Zn>Cu>Mn>S e, na polpa, foi Fe>Zn>Mn>Cu>S. A casca apresentou os níveis mais altos de inibidores de tripsina e atividade hemaglutinante. Os teores de compostos fenólicos foram relativamente baixos no fruto.

RESUMEN

The atemoya is a hybrid fruit derived from the cross between the sugar apple (fruta-do-conde), better known as ata (Annona squamosa L.) with the cherimoya (Annona cherimola Mill.). The aim of this research was to characterize the chemical constituents of the fractions skin, pulp and seed of the hybrid fruit atemoya, variety Gefner. The fruits purchased and selected were weighed and measured. They were separated into skin, pulp, seed and floral axis which were also weighted to determine their proportions. For the rest of the fruits, the fractions were separated into 7 replicates of 13 fruits. Then, the fractions skin, pulp and seeds were freeze-dried and stored in freezer. The proportion of the fruit fractions, the centesimal composition, ascorbic acid, total sugars, minerals and some bioactive compounds were determined. The pulp represented about 60% of the fruit weight, while the skin 28.13% and the seeds 8.34%. The fruit presented on the average 56 seeds, with longitudinal diameter of 10.79 cm and transversal diameter of 26.64 cm. The largest contents of crude protein, ether extract and dietary fiber were found in both seeds and skin. The skin stood out in the ash contents. The pulp showed the highest contents of ascorbic acid and total sugars in relation to the other fractions. The order of the composition of macronutrients in the skin, pulp and seeds of the atemoya was K>P>Ca>Mg; for the skin and seed micronutrients were Fe>Zn>Cu>Mn>S and in the pulp were Fe>Zn>Mn>Cu>S. The skin presented the highest levels of trypsin inhibitors and hemagglutinating activity. The phenolic compounds were relatively low in the fruit.

A atemoia é um fruto híbrido derivado do cruzamento entre a fruta-do-conde, mais conhecida como ata (Annona squamosa L.), com a cherimoia (Annona cherimola Mill.). Este trabalho foi realizado com o objetivo de caracterizar os constituintes químicos das frações casca, polpa e semente de atemoia Gefner. Os frutos adquiridos foram selecionados, pesados e medidos. Foram separados em casca, polpa, semente e eixo floral, que também foram pesados para determinar suas proporções. Para o restante dos frutos, foram separadas as frações em sete repetições de 13 frutos. Em seguida, as frações casca, polpa e sementes foram liofilizadas e armazenadas em freezer. Foi determinada a proporção das frações do fruto, a composição centesimal, o ácido ascórbico, os açúcares totais, os minerais e alguns compostos bioativos. A polpa representou cerca de 60% do peso do fruto, enquanto a casca 28,13% e as sementes 8,34%. O fruto apresentou, em média, 56 sementes, com diâmetro longitudinal de 10,79cm e diâmetro transversal de 26,64cm. Os maiores teores de proteína bruta, extrato etéreo e fibra alimentar foram encontrados nas sementes e casca. A casca se destacou nos teores de cinzas. A polpa apresentou os maiores teores de ácido ascórbico e açúcares totais em relação às outras frações. A ordem da composição de macronutrientes na casca, na polpa e nas sementes da atemoia foi K>P>Ca>Mg; para os micronutrientes na casca e nas sementes, foi Fe>Zn>Cu>Mn>S e, na polpa, foi Fe>Zn>Mn>Cu>S. A casca apresentou os níveis mais altos de inibidores de tripsina e atividade hemaglutinante. Os teores de compostos fenólicos foram relativamente baixos no fruto.

RESUMEN

The atemoya is a hybrid fruit derived from the cross between the sugar apple (fruta-do-conde), better known as ata (Annona squamosa L.) with the cherimoya (Annona cherimola Mill.). The aim of this research was to characterize the chemical constituents of the fractions skin, pulp and seed of the hybrid fruit atemoya, variety Gefner. The fruits purchased and selected were weighed and measured. They were separated into skin, pulp, seed and floral axis which were also weighted to determine their proportions. For the rest of the fruits, the fractions were separated into 7 replicates of 13 fruits. Then, the fractions skin, pulp and seeds were freeze-dried and stored in freezer. The proportion of the fruit fractions, the centesimal composition, ascorbic acid, total sugars, minerals and some bioactive compounds were determined. The pulp represented about 60% of the fruit weight, while the skin 28.13% and the seeds 8.34%. The fruit presented on the average 56 seeds, with longitudinal diameter of 10.79 cm and transversal diameter of 26.64 cm. The largest contents of crude protein, ether extract and dietary fiber were found in both seeds and skin. The skin stood out in the ash contents. The pulp showed the highest contents of ascorbic acid and total sugars in relation to the other fractions. The order of the composition of macronutrients in the skin, pulp and seeds of the atemoya was K>P>Ca>Mg; for the skin and seed micronutrients were Fe>Zn>Cu>Mn>S and in the pulp were Fe>Zn>Mn>Cu>S. The skin presented the highest levels of trypsin inhibitors and hemagglutinating activity. The phenolic compounds were relatively low in the fruit.

A atemoia é um fruto híbrido derivado do cruzamento entre a fruta-do-conde, mais conhecida como ata (Annona squamosa L.), com a cherimoia (Annona cherimola Mill.). Este trabalho foi realizado com o objetivo de caracterizar os constituintes químicos das frações casca, polpa e semente de atemoia Gefner. Os frutos adquiridos foram selecionados, pesados e medidos. Foram separados em casca, polpa, semente e eixo floral, que também foram pesados para determinar suas proporções. Para o restante dos frutos, foram separadas as frações em sete repetições de 13 frutos. Em seguida, as frações casca, polpa e sementes foram liofilizadas e armazenadas em freezer. Foi determinada a proporção das frações do fruto, a composição centesimal, o ácido ascórbico, os açúcares totais, os minerais e alguns compostos bioativos. A polpa representou cerca de 60% do peso do fruto, enquanto a casca 28,13% e as sementes 8,34%. O fruto apresentou, em média, 56 sementes, com diâmetro longitudinal de 10,79cm e diâmetro transversal de 26,64cm. Os maiores teores de proteína bruta, extrato etéreo e fibra alimentar foram encontrados nas sementes e casca. A casca se destacou nos teores de cinzas. A polpa apresentou os maiores teores de ácido ascórbico e açúcares totais em relação às outras frações. A ordem da composição de macronutrientes na casca, na polpa e nas sementes da atemoia foi K>P>Ca>Mg; para os micronutrientes na casca e nas sementes, foi Fe>Zn>Cu>Mn>S e, na polpa, foi Fe>Zn>Mn>Cu>S. A casca apresentou os níveis mais altos de inibidores de tripsina e atividade hemaglutinante. Os teores de compostos fenólicos foram relativamente baixos no fruto.

RESUMEN

Schistosomiasis is a parasitic disease which kills a half million people per year, all over the world. Praziquantel (PZQ) is the drug-of-choice for schistosomiasis because of its effectiveness, ease of administration, and low cost. However, poor solubility restricts its delivery, especially via the oral route. In this study, we describe beta-cyclodextrin (beta-CD) complexation as an alternative to improve the PZQ bioavailability. Physicochemical analysis were performed to characterize the inclusion complex formed between PZQ and beta-CD. Differential scanning calorimetry (DSC) thermograms and morphological analysis using scanning electronic microscopy (SEM) gave evidences of the complex formation. Diffusion NMR experiments allowed determination of the fraction of PZQ bound to beta-CD (37%) and the association constant (941 +/- 47 M(-1)). The in vivo evaluation of the complexation on the effect of PZQ was performed on mice infected with Schistosoma mansoni (BH strain); after 15 days of treatment with the PZQ:beta-CD complex the efficacy, evaluated by the number of remaining alive worms, was 99%, against 59% elicited by plain PZQ.

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Praziquantel (PZQ) is a broadly effective anthelminthic drug available for human and veterinary use, being the drug of choice for the treatment of all forms of schistosomiasis. Nevertheless, large doses are required in order to achieve adequate concentrations at the target site due to the poor solubility of PZQ and its significant first pass metabolism. To improve it, avoiding efficiency loss, we have designed a controlled-release system, in which PZQ was encapsulated in beta-cyclodextrin (beta-CD). The inclusion complexes between PZQ/beta-CD were studied at two different stoichiometries 1:1 and 1:2, through experimental and theoretical analysis. Molecular modeling calculations were used to foresee the better stoichiometry of the complex formed as well as the possible orientations of PZQ inside the beta-CD cavity. The complexes prepared were analyzed through H1 two-dimensional nuclear magnetic resonance (H1 2D-NMR) experiments, which provide (evidences) for the 1:1 complexation of PZQ/beta-CD. H1 2D-NMR also revealed details of PZQ/beta-CD molecular interaction, in which the isoquinoline ring of praziquantel is located inside the beta-CD cavity. Finally, phase-solubility diagrams revealed a five-fold increase in praziquantel water solubility upon addition of increasing beta-CD concentrations up to 16 mM, corresponding to the solubility of beta-CD itself. The solubilization profile is consistent with 1:1 stoichiometry of the PZQ/beta-CD complex while the solubilization effect will certainly increase the pharmacological activity of praziquantel.

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In this work the interaction of Hydroxyzine, Promethazine and Thioridazine with Langmuir films of dipalmitoylphosphatidylcholine (dpPC) and dipalmitoylphosphatidic acid (dpPA), is studied. Temporal variations in lateral surface pressure (pi) were measured at different initial pi (pi(i)), subphase pH and drug-concentration. Drugs with the smallest (PRO) and largest (HYD) molecular size exhibited the lowest adsorption (k(a)) and the highest desorption (k(d)) rate constant values, respectively. The affinity binding constants (K(b)) obtained in monolayers followed the same profile (K(b,PRO) < K(b,HYD) < K(b,THI)) of the egg-PC/water partition coefficients (P) determined in bilayers. The drug concentration required to reach the half-maximal Deltapi at pi(i) = 14 mN/m (K(0.5)), was very sensitive to pH. The maximal increment in pi upon drug incorporation into the monolayer (deltapi(max)) will depend on the phospholipid collapse pressure (pi(c)), the monolayers's compressibility and drug's size, shape and charge. The higher pi(c) of dpPC lead to higher pi(cut-off) values (maximal pi allowing drug penetration), if compared with dpPA. In dpPC and dpPA pi(cut-off) decreased as a function of the molecular size of the uncharged drugs. In dpPA, protonated drugs became electrostatically trapped at the monolayer surface hence drug penetration, monolayer deformation and pi increase were impaired and the correlation between pi(cut-off) and drug molecular size was lost.

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JUSTIFICATIVA E OBJETIVOS: O desenvolvimento de sistemas de liberação controlada tem sido alvo de pesquisas há pelo menos quatro décadas. Desde que foi sugerida sua aplicação na indústria farmacêutica, muitos resultados foram obtidos, especialmente na manipulação molecular de carreadores e no estudo de suas interações com as drogas encapsuladas. Esses novos carreadores têm a vantagem de contornar propriedades físico-químicas limitantes (como a solubilidade aquosa ou em membranas) das drogas encapsuladas, melhorando assim a farmacodinâmica (potencialização do efeito terapêutico), farmacocinética (controle da absorção e distribuição tecidual) e os efeitos toxicológicos (redução da toxicidade local e sistêmica) das mesmas. Entre os principais carreadores, destacam-se os lipossomas e as ciclodextrinas, que vêm trazendo inúmeras vantagens no desenvolvimento de formulações para liberação controlada de anestésicos locais. Este trabalho de revisão objetiva descrever a interação de anestésicos locais com lipossomas ou ciclodextrinas, o desenvolvimento das pesquisas básica e clínica nessa área, além da aplicabilidade terapêutica dessas formulações. CONTEUDO: Lipossomas têm a capacidade de veicular drogas em órgãos-alvo, disponibilizando apenas uma fração - liberação controlada - para o sítio de ação. Já as ciclodextrinas alteram a intensidade e a duração do efeitos das drogas através da baixa absorção sistêmica do complexo...

BACKGROUND AND OBJECTIVES: Many researchers in the last four decades have been devoted to the development of drug-delivery systems. Since its first application in the pharmaceutical industry, many results have been obtained especially in the molecular manipulation of carriers and their interaction with encapsulated drugs. These new carriers have the advantage of bypassing encapsulated drugs restraining physicochemical properties (such as water or membrane solubility), thus improving pharmacodynamics (therapeutic effect potentiation), pharmacokinetics (control of tissue absorption and distribution) and toxic effects (lower local and systemic toxicity). Liposomes and cyclodextrins are among the most important carriers which have shown to be quite advantageous in the development of drug-delivery systems for local anesthetics. This study aimed at reviewing the interaction of local anesthetics with liposomes and cyclodextrins, the development of basic and applied research on the field, in addition to therapeutic applicability of these formulations. CONTENTS: Liposomes have the ability to control drug delivery to target tissues, fractionating drug release in its site of action. Cyclodextrins, on the other hand, change intensity and duration of effects due to low systemic drug absorption...

JUSTIFICATIVA Y OBJETIVOS: El desenvolvimiento de sistemas de liberación controlada ha sido motivo de pesquisas desde cuatro décadas por lo menos. Desde que fue sugerida su aplicación en la industria farmacéutica, fueron obtenidos muchos resultados, especialmente en la manipulación molecular de carreadores y en el estudio de sus interacciones con las drogas encapsuladas. Esos nuevos carreadores tienen la ventaja de contornar propiedades físico-químicas limitantes (como la solubilidad acuosa o en membranas) de las drogas encapsuladas, mejorando asi la farmacodinámica (potencialización del efecto terapéutico), farmacocinética (control de la absorción y distribución de tejidos) y los efectos toxicológicos (reducción de la toxicidad local y sistémica) de las mismas. Entre los principales carreadores, se destacan los liposomas y las ciclodextrinas, que están trayendo innúmeras ventajas en el desarrollo de formulaciones para liberación controlada de anestésicos locales. Este trabajo de revisión, objetiva describir la interacción de anestésicos locales con liposomas o ciclodextrinas, el desarrollo de las pesquisas básica y clínica en esa área, además de la aplicabilidad terapéutica de esas formulaciones. CONTENIDO: Liposomas tienen la capacidad de transportar drogas en órganos-clave, disponibilizando apenas una fracción - liberación controlada - para el sitio de acción. Ya las ciclodextrinas alteran la intensidad y la duración de efectos de las drogas a través de la baja absorción sistémica del complejo...

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BACKGROUND AND OBJECTIVES: Many researchers in the last four decades have been devoted to the development of drug-delivery systems. Since its first application in the pharmaceutical industry, many results have been obtained especially in the molecular manipulation of carriers and their interaction with encapsulated drugs. These new carriers have the advantage of bypassing encapsulated drugs restraining physicochemical properties (such as water or membrane solubility), thus improving pharmacodynamics (therapeutic effect potentiation), pharmacokinetics (control of tissue absorption and distribution) and toxic effects (lower local and systemic toxicity). Liposomes and cyclodextrins are among the most important carriers which have shown to be quite advantageous in the development of drug-delivery systems for local anesthetics. This study aimed at reviewing the interaction of local anesthetics with liposomes and cyclodextrins, the development of basic and applied research on the field, in addition to therapeutic applicability of these formulations. CONTENTS: Liposomes have the ability to control drug delivery to target tissues, fractionating drug release in its site of action. Cyclodextrins, on the other hand, change intensity and duration of effects due to low systemic drug absorption. Basic and clinical studies have pointed out that the administration of local anesthetics in liposome or cyclodextrin formulations induces slow release of the drugs, prolonging the anesthetic action and decreasing cardiac and nervous systems toxicity. CONCLUSIONS: Although studies are still in progress, drug-delivery systems are flagging a new direction for the development of safer and more effective local anesthetic formulations.

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We examined the effect of uncharged lidocaine on the structure and dynamics of egg phosphatidylcholine (EPC) membranes at pH 10.5 in order to assess the location of this local anesthetic in the bilayer. Changes in the organization of small unilamellar vesicles were monitored either by electron paramagnetic resonance (EPR)-in the spectra of doxyl derivatives of stearic acid methyl esters labeled at different positions in the acyl chain (5-, 7-, 12- and 16-MeSL)-or by fluorescence, with pyrene fatty-acid (4-, 6-, 10- and 16-Py) probes. The largest effects were observed with labels located at the upper positions of the fatty-acid acyl-chain. Dynamic information was obtained by 1H-NMR. Lidocaine protons presented shorter longitudinal relaxation times (T(1)) values due to their binding, and consequent immobilization to the membrane. In the presence of lidocaine the mobility of all glycerol protons of EPC decreased, while the choline protons revealed a higher degree of mobility, indicating a reduced participation in lipid-lipid interactions. Two-dimensional Nuclear Overhauser Effect experiments detected contacts between aromatic lidocaine protons and the phospholipid-choline methyl group. Fourier-transform infrared spectroscopy spectra revealed that lidocaine changes the access of water to the glycerol region of the bilayer. A "transient site" model for lidocaine preferential location in EPC bilayers is proposed. The model is based on the consideration that insertion of the bulky aromatic ring of the anesthetic into the glycerol backbone region causes a decrease in the mobility of that EPC region (T(1) data) and an increased mobility of the acyl chains (EPR and fluorescence data).

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