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INTRODUCTION: Human Immunodeficiency Virus (HIV) infection is still a major global problem, whose drug treatment consists of prophylactic prevention and antiretroviral combination therapy for better pharmacological efficacy and control of the circulating virus. However, there are still pharmacological problems that need to be overcome, such as low aqueous solubility of drugs, toxicity, and low patient adherence. Drug delivery technologies can be used to overcome these barriers. OBJECTIVE: This review summarized the latest drug delivery systems for HIV treatment. Initially, an overview of the current therapy was presented, along with the problems it presents. Then, the latest drug delivery systems used to overcome the challenges imposed in conventional HIV therapy were discussed. CONCLUSION: This review examines innovative approaches for HIV treatment, where various drug delivery systems have shown significant advantages, such as high drug encapsulation, improved solubility, and enhanced bioavailability both in vitro and in vivo. Strategies like cyclodextrins, solid dispersions, microneedles, and nanoparticles are explored to address challenges in drug solubility, bioavailability, and administration routes. Despite progress, obstacles like limited clinical trials and industrial scalability hinder the widespread adoption of these formulations, emphasizing the need for further research and collaboration to optimize and ensure accessibility of innovative HIV therapies, mainly in regions where access to HIV treatment is scarce and remains a challenge.

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Due to its characteristic aroma and diverse therapeutic properties, lemongrass essential oil (LEO) has garnered increased attention in the pharmaceutical, food, and cosmetic industries. However, LEO's volatile nature, low chemical stability, and limited solubility in water limits its applications in the industry. Micro- and nanoencapsulation technologies emerge as a promising solution to overcome these challenges. A systematic methodology involving keyword searches in databases was employed to gather relevant literature on LEO micro- and nanoencapsulation, providing an extensive overview of techniques, processes, encapsulating materials, and possible applications. Beyond established methods, emerging techniques were explored. This review highlights the critical role of encapsulation in enhancing the thermal and chemical stability, applicability, bioavailability, and controlled release of LEO.

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The use of nanocellulose in pharmaceutics is a trend that has emerged in recent years. Its inherently good mechanical properties, compared to different materials, such as its high tensile strength, high elastic modulus and high porosity, as well as its renewability and biodegradability are driving nanocellulose's industrial use and innovations. In this sense, this study aims to conduct a search of patents from 2011 to 2023, involving applications of nanocellulose in pharmaceuticals. A patent search was carried out, employing three different patent databases: Patentscope from World Intellectual Property Organization (WIPO); Espacenet; and LENS.ORG. Patents were separated into two main groups, (i) nanocellulose (NC) comprising all its variations and (ii) bacterial nanocellulose (BNC), and classified into five major areas, according to their application. A total of 215 documents was retrieved, of which 179 were referred to the NC group and 36 to the BNC group. The NC group depicted 49.7%, 15.6%, 16.2%, 8.9% and 9.5% of patents as belonging to design and manufacturing, cell culture systems, drug delivery, wound healing and tissue engineering clusters, respectively. The BNC group classified 44.5% of patents as design and manufacturing and 30.6% as drug delivery, as well as 5.6% and 19.4% of patents as wound healing and tissue engineering, respectively. In conclusion, this work compiled and classified patents addressing exclusively the use of nanocellulose in pharmaceuticals, providing information on its current status and trending advancements, considering environmental responsibility and sustainability in materials and products development for a greener upcoming future.

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Objective: The aim of this research was to evaluate the efficacy of a topical formulation containing chitosan-chamomile microparticles in cutaneous healing in rats. Method: Male Wistar rats (n=57) were randomly distributed into three groups: treatment; vehicle; and control. Evaluations were performed on days 2, 7 and 14 after the surgical procedure using skin lesion photography, and histological and biochemical analyses. Results: The results showed that there was no difference in the healing index and in the histological analysis of the inflammatory infiltrate among groups. Fibrogenesis was more significant in the group treated with the test formulation at day 7, and angiogenesis was greater in the vehicle and chamomile groups at day 2. The quantification of hydroxyproline showed a higher amount of collagen in the group treated with chamomile, mainly at day 14, although the histological quantification of collagen showed no difference between the groups. Conclusion: From the results of this study, it can be concluded that the formulation, although it had no effect on the healing time, improved the quality of the cicatricial tissue formed with a greater quantity of fibroblasts and collagen.

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INTRODUCTION: Leprosy is a neglected, infectious, granulomatous and chronic disease caused by the pathological agent Mycobacterium leprae. The course of the disease is more aggressive in patients under 15 years of age, but the current treatment offered worldwide consists of solid forms, by the combination of antibiotics such as rifampicin, clofazimine and dapsone. This represents results in lack of adherence in pediatric patients and drug therapy failure, although numerous formulations and technologies have already been developed. AREA COVERED: This study aims to analyze the technological evolution of the pharmaceutical treatment of leprosy, aimed at children. A review of patents around the world was conducted to look for technical and clinical aspects of formulations and devices. EXPERT OPINION: Innovative formulations for pediatric patients were classified according to the routes of administration as oral, inhalable, injectable and transdermal. The formulations were organized as alternatives for pediatric therapy, taking into account the physicochemical aspects of drugs and the physiological aspects of pediatric patients. Among the difficulties for the patented formulations to reach the market, of special note is the low stability of the physicochemical characteristics of the drugs. Optimization of formulations would favor the pediatric treatment of leprosy, aiming at therapeutic success.

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Surfactants are amphiphilic molecules of great interest in the pharmaceutical field which are used in combination with other adjuvants to solubilize poorly soluble drugs, improve their dissolution profile, promote permeation, improve drug delivery, enhance stabilization, among other characteristics. Literature shows that surfactants are included in several pharmaceutical compositions: tablets, solid dispersions, emulsions, microemulsions, nanoemulsions, liposomes and niosomes. This review aims to elucidate the different classes of surfactants based on their charges (cationic, anionic, nonionic, zwitterionic, and dimeric), the micelles formation process, and how surfactant molecules geometry can affect this phenomenon. Moreover, current studies regarding the benefits of surfactants in the development of formulations are presented. Finally, a discussion on how charges and chain length of surfactants can affect the stratum corneum epithelial cells leading to increased permeation or skin irritability is reported.

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Candidiasis is a common opportunistic infection caused by fungi of the Candida genus that affects mainly mucocutaneous tissues (e.g., vaginal, oral, and mammary). This condition has been known for a long time; thus, innumerous topical and systemic treatments are already available on the market worldwide. Yet, recurrent superficial candidiasis (RSC) is an expected outcome, still lacking effective and convenient treatments. Although several individual conditions may contribute to disease recurrence, biofilms' presence seems to be the main etiological factor contributing to antifungal resistance. More than proposing novel antifungal agents, current research seems to be focusing on improving the pharmaceutical technology aspects of formulations to address such a challenge. These include extending and improving intimate contact of drug delivery systems with the mucocutaneous tissues, increasing drug loading dose, and enhancing topical drug permeation. This review discusses the current understanding of the RSC and the use of pharmaceutical technology tools in obtaining better results. Even though several drawbacks of conventional formulations have been circumvented with the help of nano- or microencapsulation techniques and with the use of mucoadhesive formulation excipients, many challenges remain. In particular, the need to mask the unpalatable taste of formulations for the treatment of oral candidiasis, and the necessity of formulations with a "dryer" sensorial feeling and improved performances in providing higher bioavailability for the treatment of mammary and vaginal candidiasis.

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Carvedilol (CRV) is a non-selective blocker of α and ß adrenergic receptors, which has been extensively used for the treatment of hypertension and congestive heart failure. Owing to its poor biopharmaceutical properties, CRV has been incorporated into different types of drug delivery systems and this necessitates the importance of investigating their compatibility and stability. In this sense, we have investigated the applicability of several electroanalytical tools to assess CRV compatibility with lipid excipients. Voltammetric and electrochemical impedance spectroscopy techniques were used to evaluate the redox behavior of CRV and lipid excipients. Results showed that Plurol® isostearic, liquid excipient, and stearic acid presented the greatest anode peak potential variation, and these were considered suitable excipients for CRV formulation. CRV showed the highest stability at room temperature and at 50 °C when mixed with stearic acid (7% w/w). The results also provided evidence that electrochemical methods might be feasible to complement standard stability/compatibility studies related to redox reactions.

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Dear colleagues: The Organizing Committee of the V International Congress on Pharmacology of Vaccines (VacciPharma 2020) organized by the Cuban Society of Pharmacology, BioCubaFarma and the International Union of Basic and Clinical Pharmacology (IUPHAR) would like to invite you to participate in this important event, scheduled for June 14 to 18, 2020 at the Convention Centre of the Melia Marina Varadero Hotel, Varadero Beach, Matanzas, Cuba. The Congress will be formed by different workshops and symposia such as: Meningococcal and Gonococcal vaccines Pneumococcal vaccines Pertussis and combined vaccines Enteric vaccines Leptospira vaccines Viral vaccines Animal models in vaccine development, QC and 3Rs Vaccine technology and bioprocess Vaccine technology transfers Patent, business and international cooperation VacciPharma 2020 is sponsored by: Cuban Society of Pharmacology (SCF) International Union of Basic and Clinical Pharmacology (IUPHAR) Latin-American Association of Pharmacology (ALF) PAHO / WHO BioCubaFarma National research centers: Finlay Vaccine Institute (IFV); Center of Genetic Engineering and Biotechnology (CIGB); Center of Molecular Immunology (CIM); Center for Control of Drugs, Equipment and Medical Devices (CECMED); National Center for Animal and Plant Health (CENSA); Tropical Medicine Institute Pedro Kourí (IPK); National Center for Biopreparations (BioCEN); Center for Drug Research and Development (CIDEM); Center for Clinical Trials (CENCEC); among others International Manufacturers and Companies The key objectives of the Congress are: To provide a progressive state-of-the-art report for scientists, manufacturers, governmental authorities and healthcare workers, who need to be updated about the latest scientific developments for human vaccines, including basic science, product development, market introduction, immunization programs and epidemiological surveillance. To promote the scientific collaboration among experts and institutions through the experience exchange, the presentation of results and the discussion on the conference topics. To accelerate progress in the development of vaccines and the acceptance and introduction of new methods and technologies. Opening lectures, oral presentations and posters will provide you the opportunity to be involved in a high quality congress to discuss about the progress in the field of vaccinology and pharmacology sciences. Deadline for registration and abstract submission: April 15th, 2020 Further information can be found at the VacciPharma 2020 Website: www.immunovaccipharma.com

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Anxiety in the world population has increased significantly; the problem has encouraged studies regarding innovative alternatives for treatment. Research with Citrus aurantium L. essential oil (CEO) has revealed positive results with anxiolytic effects in both animals and humans. However, certain limitations affect its storage and preservation, its efficiency in therapy, and determination of adequate posologies. The potential use of cyclodextrins as drug carriers has been successfully explored. This study aims to assess the anxiolytic potential of a CEO/2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) inclusion complex. Preparation of the inclusion complex was performed using the Alpha 1-2 LDplus lyophilizer. To allow formation, and avoid loss of volatiles to the atmosphere, Limonene (LIM), the main compound in CEO, together with HP-ß-CD in a molar ratio of (1: 1M) was dispersed in ethanol for 36 hours using a laboratory shaker at room temperature (25°C). Non-clinical murine pharmacological tests were performed for anxiety assessment in experimental and control groups. To assess anxiety and motor impairment, the animals were evaluated using the elevated plus maze, open field, and rota-rod tests. Satisfactory results of the anxiolytic effect of the OEC complexed in HP-ß-CD were observed, with the indication of an potentiation of the effect with doses lower than 500 mg/kg and 250 mg/kg complexed, suggesting improvement in the anxiolytic properties of the OEC.

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This review aims to provide a critical review of the biological performance of natural and synthetic substances complexed with cyclodextrins, highlighting: (i) inclusion complexes with cyclodextrins and their biological studies in vitro and in vivo; (ii) Evaluation and comparison of the bioactive efficacy of complexed and non-complexed substances; (iii) Chemical and biological performance tests of inclusion complexes, aimed at the development of new pharmaceutical products. Based on the evidence presented in the review, it is clear that cyclodextrins play a vital role in the development of inclusion complexes which promote improvements in the chemical and biological properties of the complexed active principles, as well as providing improved solubility and aqueous stability. Although the literature shows the importance of their ability to help produce innovative biotechnological substances, we still need more studies to develop and expand their therapeutic properties. It is, therefore, very important to gather together evidence of the effectiveness of inclusion complexes with cyclodextrins in order to facilitate a better understanding of research on this topic and encourage further studies.

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Caused by Trypanosoma cruzi, Chagas disease is responsible for public health problems greater in magnitude than those attributed to malaria, schistosomiasis, or leishmaniasis. A factor in the socioeconomic development of poor countries, Chagas disease can cause death due to a high parasitic burden during its acute phase due and irreversible damage in organs such as the heart, esophagus, and colon during its chronic phase, even when the number of parasites is minimal. For treating Chagas disease, benznidazole (BNZ) remains the drug of choice and, in Latin America, the only drug on the market for treating the disease. However, BNZ has exhibited insufficient activity in the chronic phase of Chagas disease, required administration in large doses, prolonged treatment, and shown a high incidence of adverse reactions (vomiting, rash, peripheral neuropathy, and spinal cord depression), toxicity, and low solubility in water. As an antidote, pharmaceutical technologies have been introduced that can improve BNZ's solubility and dissolution, as well as reduce side effects in light of its bioavailability, all of which can enhance therapy for Chagas disease. In response to that trend, by conducting a literature review, we sought to identify current pharmaceutical technologies used in tandem with BNZ to improve therapy for Chagas disease. Documented techniques include emulsion and microemulsion formation, solutions, parenteral formulas, micronization, and drug delivery systems supported by the development of nanoparticles and cyclodextrins, solid dispersions, and the use of metal-organic frameworks as innovative excipients. Such technologies increase the water solubility of BNZ by 4-25-fold on dissolution and an 85% release with efficacy in only a few minutes, as recorded during a viability experiment with nanoparticle suspensions. That experiment demonstrated the need for a lower concentration of BNZ to kill 50% of trypomastigote forms of T. cruzi, described in terms of the formation of BNZ-cyclodextrin complexes, and modulating and vectoring of the antichagasic by using metal-organic frameworks. Altogether, the promising results of research identified can enable strategies to improve solubility and efficacy of BNZ, as well as therapy for Chagas disease.

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Terpenes constitute the largest class of natural products and are important resources for the pharmaceutical, food and cosmetics industries. However, due to their low water solubility and poor bioavailability there has been a search for compounds that could improve their physicochemical properties. Cyclodextrins (natural and derived) have been proposed for this role and have been complexed with different types of terpenes. This complexation has been demonstrated by using analytical techniques for characterizing complexes such as DSC, NMR, XRD, FTIR, and TGA. The formation of inclusion complexes has been able to improve drug characteristics such as bioavailability, solubility and stability; and to enhance biological activity and efficacy. This review shows strong experimental evidence that cyclodextrins improve the pharmacological properties of terpenes, and therefore need to be recognized as being possible targets for clinical use.

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Ulceration of the foot in diabetes is common and disabling, and frequently leads to amputation of the leg. The pathogenesis of foot ulceration is complex, clinical presentation variable and management requires early expert assessment. Despite treatment, ulcers readily become chronic wounds. Chronic wounds are those that remain in a chronic inflammatory state failing a normal healing process patterns. This is partially caused by inefficient eradication of opportunistic pathogens like Pseudomonas aeruginosa. We propose its control or eradication will promote wound healing. Lactobacillus plantarum cultures supernatants (LAPS) shows antipathogenic and pro-healing properties. The main objective was to design two pharmaceutical dosage forms by using LAPS as active pharmaceutical ingredient and to perform its quality control, in vitro activity conservation tests and human trials (safety evaluation). Both selected formulations reach the technological quality expected for 120 days, shows adequate occlusive characteristics and proper adhesion to human skin. From the in vitro release assays were found that LAPS shows adequate release from matrix and maintain its antimicrobial and anti-biofilm activity. First human trials were developed and neither edema nor erythema on healthy skin voluntaries was found. We conclude that C80 and C100 are adequate for their use in future clinical trials to demonstrate a comprehensive therapeutic effectiveness in ischemic chronic wounds.

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Abstract: This article has two parts. The first discusses the relationship between industry and health interests based on three different but non-mutually exclusive "logics": (a) independent; (b) divergent; and (c) convergent. The second part describes the experience at the Brazilian National Institute of Traumatology and Orthopedics (INTO) with a technology management model. The accumulated expertise in orthopedics at INTO can favor Brazil's domestic medical equipment industry without jeopardizing the country's social health needs. This means directing the production of feasible technologies adapted to the national reality, with a focus on safety and quality, without burdening the public coffers and by overcoming the country's dependency on imported products. The proposal is to promote socioeconomic development through a virtuous circle by attracting reserves and fomenting national competitiveness in domestic and foreign markets while improving social conditions and access to health.

Resumen: Este artículo está dividido en dos partes. En la primera, se discute cómo se relacionan los intereses productivos y la salud, a partir de tres "lógicas" o perspectivas diferentes, que no son mutuamente excluyentes: (a) independiente; (b) divergente; (c) convergente. En la segunda, se describe la experiencia del Instituto Nacional de Traumatología y Ortopedia (INTO) en el montaje de un modelo de gestión de tecnología. El conocimiento internalizado en ortopedia del INTO puede favorecer la industria nacional de equipos médicos, sin abandonar las necesidades sociales brasileñas en salud. Esto es, dirigir la producción de tecnologías viables y adaptadas a la realidad nacional, centrándose en la seguridad y calidad, sin ser onerosos para el erario público y abandonando la dependencia de productos importados. La propuesta es promover un progreso socioeconómico que construya un ciclo virtuoso, con el fin de atraer divisas y fomentar la competitividad nacional en mercados internos y externos, mejorando las condiciones sociales y de acceso a la salud.

Resumo: Este artigo está dividido em duas partes. Na primeira, discute-se como se relacionam os interesses produtivos e a saúde a partir de três "lógicas" ou perspectivas diferentes que não são mutuamente excludentes: (a) independente; (b) divergente e (c) convergente. Na segunda, descreve-se a experiência do Instituto Nacional de Traumatologia e Ortopedia (INTO) na montagem de um modelo de gestão de tecnologia. O conhecimento internalizado em ortopedia do INTO pode favorecer a indústria nacional de equipamentos médicos sem abandonar as necessidades sociais brasileiras de saúde. Isto é, direcionar a produção de tecnologias viáveis e adaptadas à realidade nacional, com foco em segurança e qualidade, sem onerar os cofres públicos e abandonando a dependência de produtos importados. A proposta é a de promover um desenvolvimento socioeconômico que construa um ciclo virtuoso, por atrair divisas e fomentar a competitividade nacional em mercados internos e externos, melhorando as condições sociais e de acesso à saúde.

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This article reports the development of a pharmaceutical product containing vegetable actives from a Brazilian medicinal plant. The possibility of forming a microemulsion using Pterodon emarginatus ("sucupira") oil was evaluated and the anti-inflammatory potential of this microemulsion was also examined. A formulation was developed using P. emarginatus oil, a mixture of ethoxylated Castor Oil (Ultramone(r) R-540/propylene glycol 2:1) (surfactant/cosurfactant) and distilled water at a ratio of 10:15:75, respectively. The microemulsion which was selected was then subjected to the preliminary stability test and analyzed in terms of average diameter of droplets, pH, zeta potential, and polydispersity index, on the 1st, 7th, 15th, and 30th days after preparation and stored at different temperatures (5 ± 2 °C, 25 ± 2 °C, and 40 ± 2 °C). The anti-inflammatory in vivo activity of both oil and formulation were evaluated, using the experimental model of croton oil-induced ear edema. The preliminary stability test showed that the microemulsion stored at 5 and 25 °C retained its original features throughout the 30-day period. The anti-inflammatory potential of both oil and formulation was shown to be statistically significant (p < 0.001), when compared to the control group, however, the microemulsion proved to be more effective (p < 0.05) than the oil when applied directly to the ear.

Descrevemos o desenvolvimento de um produto farmacêutico contendo ativo vegetal baseado em uma planta medicinal brasileira. Foi avaliada a habilidade de formação de uma microemulsão à base do óleo de Pterodon emarginatus (sucupira) e seu potential anti-inflamatório. Uma formulação foi desenvolvida utilizando o óleo de P. emarginatus, mistura de óleo de mamona etoxilado (Ultramona(r) R-540)/propilenoglicol (2:1) (tensoativo/cotensoativo) e água destilada, na proporção de 10:15:75, respectivamente. A microemulsão selecionada foi submetida ao teste preliminar de estabilidade e foi analisada quanto ao diâmetro médio das gotículas, pH, potential zeta e índice de polidispersão, no 1º, 7º, 15º e 30º dias após o preparo e foram estocadas em diferentes temperaturas (5±2 °C, 25±2 °C e 40±2 °C). Avaliaram-se a atividade anti-inflamatória in vivo do óleo de sucupira e da formulação, usando o modelo experimental do edema de orelha induzido pelo óleo de cróton. No teste preliminar de estabilidade observou-se que a formulação estocada a 5 °C e a 25 °C mantiveram suas características originais durante 30 dias. O potencial anti-inflamatório de ambos, óleo de sucupira e formulação foi estatisticamente significativo (p <0.001), quando comparado ao controle, porém a microemulsão foi mais eficiente (p <0.05) que o óleo aplicado diretamente nas orelhas dos animais.

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The aim of the work was to study the spray-drying of ethanolic extract from Amburana cearensis (Allemão) A.C. Sm., Fabaceae, in order to obtain powders with better pharmacological and technological properties for herbal medicine. A 2³ fractional factorial statistical design was used to find adequate spray-drying operating conditions (inlet air temperature; feed flow rate and air flow rate) to produce A. cearensis powder with adequate concentration of active principles (amburoside and coumarin), low moisture content and high process yield. The HPLC analyses showed that the spray-drying powder of A. cearensis production did not cause alterations in the chromatographic profile when related to the fluid extract. The most significant factor that affected the amburoside concentration was air flow rate, while the concentration of coumarin, a thermolabile molecule, was influenced mainly by inlet air temperature. The moisture content of the spray-drying powder of A. cearensis varied from 3.72 to 5.85% (w/w), while the maximal process yield was 41.1% (w/w). The present study demonstrates for the first time the best operating conditions to produce A. cearensis extract powder that were adequate when related to the coumarin and amburoside concentrations and moisture content. However, additional studies are still needed to improve mainly it technological characteristics.

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En el presente trabajo se aplicó una de las técnicas más representativas que conforman el análisis térmico, la calorimetría diferencial de barrido, para estudiar la compatibilidad entre el extracto seco de Rhizophora mangle L y distintos excipientes preseleccionados para la obtención de formulaciones a partir de esta especie vegetal. Se obtuvo como resultado la no interacción química entre el extracto vegetal seco y los excipientes

In present paper authors applied one of the more representative techniques conforming the thermal analysis, the differential scanning clometry to study the compatibility among the Rhizophora mangle L dry extract and different excipients selected to obtain the formulae from this vegetal species. As result, it was possible to obtain the non-chemical interaction between the dry vegeral extract and the excipients ones

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The treatment of diseases affecting the posterior segment of the eye is limited by the difficulty in transporting effective doses of drugs to the vitreous, retina, and choroid. Topically applied drugs are poorly absorbed due to the low permeability of the external ocular tissues and tearing. The blood-retina barrier limits drug diffusion from the systemic blood to the posterior segment, thus high doses of drug are needed to maintain therapeutic levels. In addition, systemic side effects are common. Intraocular injections could be an alternative, but the fast flowing blood supply in this region, associated with rapid clearance rates, causes drug concentration to quickly fall below therapeutic levels. To obtain therapeutic levels over longer time periods, polymeric sustained-drug release systems implanted within the vitreous are being studied for the treatment of vitreoretinal disorders. These systems are prepared using different kinds of biodegradable or non-biodegradable polymers. This review aims to demonstrate the main characteristics of these drug delivery implants and their potential for clinical application.

O tratamento de doenças do segmento posterior do olho é limitado pela dificuldade no transporte de doses efetivas de fármacos para o vítreo, retina e coróide. Os fármacos aplicados topicamente são pouco absorvidos por causa da baixa permeabilidade dos tecidos oculares externos e ao lacrimejamento. Embora a administração sistêmica seja capaz de transportar fármacos para o segmento posterior do olho, as barreiras hemato-aquosa e hematorretiniana dificultam a absorção e, normalmente, são necessárias doses elevadas, as quais estão geralmente associadas a potenciais efeitos adversos. Injeções intravitreais são capazes de transportar fármacos para o segmento posterior do olho, mas é uma técnica invasiva, pouco tolerada pelos pacientes e apresenta riscos de infecções oculares e danos aos tecidos. Visando a obtenção de níveis terapêuticos adequados de fármacos no segmento posterior do bulbo do olho por longos períodos, sistemas de liberação poliméricos implantados diretamente no vítreo estão sendo investigados para o tratamento de várias doenças vítreo-retinianas. Esses implantes podem ser preparados a partir de diferentes polímeros biocompatíveis, biodegradáveis ou não-biodegradáveis. Nesta revisão, as principais características destes implantes transportadores de fármacos são descritas, expondo suas potencialidades de aplicação clínica.

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Matrizes hidrofílicas de diclofenaco sódico e de cetoprofeno foram preparadas por meio de compressão direta ou granulação úmida seguida de compressão, utilizando-se hipromelose para modular a dissolução do fármaco. Foram também obtidos péletes de liberação prolongada de cetoprofeno, mediante extrusão-esferonização e revestimento, em leito fluidizado, com Kollicoat® EMM 30D. Um planejamento fatorial 22 foi usado para elucidar os efeitos de variáveis de formulação sobre os perfis de liberação do fármaco a partir dos sistemas em estudo, determinados empregando-se os métodos da pá e/ou Bio-Dis. No caso dos comprimidos matriciais, os efeitos do grau de viscosidade e concentração de hipromelose foram investigados. Para os péletes, avaliou-se os efeitos da granulometria e ganho de peso em revestimento. A influência do pH sobre a liberação do fármaco a partir dos sistemas preparados foi também estudada, usando-se meios de dissolução com pH 1,2-7,2. Os métodos ANOVA e teste de Tukey (comparação estatística entre porcentuais de fármaco dissolvido e/ou eficiência de dissolução), f1, f2 e Weibull foram usados para caracterizar e comparar os perfis de dissolução. O grau de viscosidade e concentração de hipromelose influenciaram a liberação de diclofenaco sádico e cetoprofeno a partir das matrizes em estudo, sendo a concentração do polímero o fator principal que governou o processo. A granulação alterou os perfis de dissolução de cetoprofeno em relação às matrizes obtidas por compressão direta, diminuindo a velocidade e modificando o mecanismo de liberação. No caso dos péletes, o ganho de peso em revestimento foi o parâmetro que exerceu maior efeito sobre a liberação do cetoprofeno, enquanto a granulometria apenas influenciou os perfis de dissolução dás formulações com maior ganho de peso em revestimento. A liberação do fármaco a partir dos sistemas em estudo aumentou com a elevação do pH, o que ocorreu devido à solubilidade pH-dependente do cetoprofeno e diclofenaco sódico.

Diclofenac sodium and ketoprofen hydrophilic matrices were prepared by direct compression or wet granulation followed by compression, using hypromellose to modulate the drug dissolution. Sustained release ketoprofen pellets were also obtained by extrusion-spheronization and fluidized bed coating with Kollicoat® EMM 30D. A 22 factorial design has been used to elucidate the effects of formulation variables on the drug release profiles from the systems in study, determined using the paddle method and Bio-Dis. In the case of matrix tablets, the effects of the viscosity grade and concentration of hypromellose were investigated. For the pellets, the effects of granulometry and weight gain were evaluated. The influence of the pH value on the drug release from the prepared systems was also studied, using pH 1,2-7,2 dissolution media. ANOVA and Tukey's test (statistical comparison between percentages of drug dissolved and/or dissolution efficiency), f1, f2 and Weibull methods were used to characterize and compare the dissolution profiles. The concentration and viscosity grade of hypromellose influenced the ketoprofen and diclofenac sodium release from the studied matrices, being the polymer concentration the main factor that has governed the process. Granulation has modified the dissolution profiles of ketoprofen in relation to the matrices obtained by direct compression, reducing the rate and modifying the mechanism of drug release. In the pellets case, weight gain was the main factor that has influenced the ketoprofen release, while ganulometry has only influenced the dissolution profiles of the formulation with the highest weight gain. Drug release from the systems under study increased with the increase of the pH value of the medium because of the diclofenac sodium and ketoprofen pH-dependent solubility.

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