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This study aimed to develop a novel ureasil-polyether transdermal hybrid matrix (U-PEO) loaded with Annona muricata concentrated extract (AMCE), which exhibits potent anti-inflammatory activity. The extract was obtained by maceration, a method that allowed for the extraction of a high concentration of flavonoids (39.27 mg/g of extract). In vivo tests demonstrated that 10 mg/kg of AMCE inhibited inflammation for 6 h. The physicochemical characterization of U-PEO with AMCE was conducted via a thermogravimetric analysis (TGA), while its surface was recorded using atomic force microscopy (AFM). The in vitro macroscopic swelling and release tests demonstrated the hydrophilic profile of the material and the percentage of AMCE released. The TGA results demonstrated that the system exhibited physical compatibility due to the thermal stability of U-PEO. Additionally, the AFM analysis revealed a rough and porous surface, with a particular emphasis on the system with AMCE. The release resulted in the liberation of 23.72% of AMCE within 24 h. Finally, the preclinical tests demonstrated that U-PEO with AMCE was also capable of effectively inhibiting inflammation for 6 h, a duration comparable to that of a commercial formulation. The results permit the advancement of the study towards the development of a transdermal system, thereby rendering its application in clinical studies feasible.

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Simvastatin (SIM) is widely prescribed to treat hyperlipidemia, despite its limitations, such as a short half-life and low oral bioavailability. To overcome these drawbacks, the development of a controlled-release formulation is desirable. This study aims to develop a microparticulate system based on cellulose acetate (ACT) obtained from Agave sisalana Perrine to promote a controlled SIM release. SIM-loaded microparticles (SMP) were prepared using the solvent emulsification-evaporation method. Several parameters were evaluated, including particle size, surface charge, morphology, encapsulation efficiency, thermochemical characteristics, crystallinity, and in vitro release profile. ACT exhibited favorable flow properties after acetylation, with a degree of substitution values superior to 2.5, as confirmed by both the chemical route and H-NMR, indicating the formation of cellulose triacetate. The obtained SMP were spherical with an average size ranging from 1842 to 1857 nm, a zeta potential of -4.45 mV, and a high SIM incorporation efficiency (98%). Thermal and XRD analyses revealed that SIM was homogeneously dispersed into the polymeric matrix in its amorphous state. In vitro studies using dialysis bags revealed that the controlled SIM release from microparticles was higher under simulated intestinal conditions and followed the Higuchi kinetic model. Our results suggest that ACT-based microparticles are a promising system for SIM delivery, which can improve its bioavailability, and result in better patient compliance.

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Curcumin (CUR) is a natural compound that can be combined with miconazole (MCZ) to improve vulvovaginal candidiasis (VVC) caused by Candida albicans treatment's efficacy. This study aimed to develop ureasil-polyether (U-PEO) vaginal ovules loaded with CUR and MCZ for the treatment of VVC. Physicochemical characterization was performed by thermogravimetry (TGA), differential thermal analysis (DTA), Fourier transform infrared spectroscopy (FTIR), and in vitro release. Antifungal assays were used to determine minimum inhibitory concentrations (MICs) and synergism between CUR and MCZ, and the activity of U-PEO ovules were performed by microdilution and agar diffusion. TGA results showed high thermal stability of the hybrid ovules. In DTA, the amorphous character of U-PEO and a possible interaction between CUR and MCZ were observed. FTIR showed no chemical incompatibility between the drugs. In vitro release resulted in 80% of CUR and 95% of MCZ released within 144 h. The MICs of CUR and MCZ were 256 and 2.5 µg/mL, respectively. After combining the drugs, the MIC of MCZ decreased four-fold to 0.625 µg/mL, while that of CUR decreased eight-fold to 32 µg/mL. Synergism was confirmed by the fractional inhibitory concentration index (FICI) equal to 0.375. U-PEO alone showed no antifungal activity. U-PEO/MCZ and U-PEO/CUR/MCZ ovules showed the greatest zones of inhibition (≥18 mm). The results highlight the potential of the ovules to be administered at a lower frequency and at reduced doses compared to available formulations.

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This study aimed to develop films of chitosan (CSF) associated with pentoxifylline (PTX) for healing cutaneous wounds. These films were prepared at two concentrations, F1 (2.0 mg/mL) and F2 (4.0 mg/mL), and the interactions between the materials, structural characteristics, in vitro release, and morphometric aspects of skin wounds in vivo were evaluated. The formation of the CSF film with acetic acid modifies the polymeric structure, and the PTX demonstrates interaction with the CSF, in a semi-crystalline structure, for all concentrations. The release for all films was proportional to the concentration, with two phases: a fast one of ≤2 h and a slow one of >2 h, releasing 82.72 and 88.46% of the drug after 72 h, being governed by the Fickian diffusion mechanism. The wounds of the mice demonstrate a reduction of up to 60% in the area on day 2 for F2 when compared to CSF, F1, and positive control, and this characteristic of faster healing speed for F2 continues until the ninth day with wound reduction of 85%, 82%, and 90% for CSF, F1, and F2, respectively. Therefore, the combination of CSF and PTX is effective in their formation and incorporation, demonstrating that a higher concentration of PTX accelerates skin-wound reduction.

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In this study, films of chitosan and 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (6CN), a 2-aminothiophene derivative with great pharmacological potential, were prepared as a system for a topical formulation. 6CN-chitosan films were characterized by physicochemical analyses, such as Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electronic microscopy (SEM). Additionally, the antifungal potential of the films was evaluated in vitro against three species of Candida (C. albicans, C. tropicalis, and C. parapsilosis). The results of the FTIR and thermal analysis showed the incorporation of 6CN in the polymer matrix. In the diffractogram, the 6CN-chitosan films exhibited diffraction halos that were characteristic of amorphous structures, while the micrographs showed that 6CN particles were dispersed in the chitosan matrix, exhibiting pores and cracks on the film surface. In addition, the results of antifungal investigation demonstrated that 6CN-chitosan films were effective against Candida species showing potential for application as a new antifungal drug.

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Cellulose acetate (ACT) is one of the most important cellulose derivatives due to its biodegradability and low toxicity, presenting itself as one of the main substitutes for synthetic materials in the development of wound dressing films. The incorporation of a N-acylhydrazonic derivative (JR19), with its promising anti-inflammatory activity, may represent an alternative for the treatment of skin wounds. This work aims to develop and to physicochemically and mechanically characterize ACT films containing JR19. The films were prepared using the 'casting' method and further characterized by thermoanalytical and spectroscopic techniques. In addition, mechanical tests and morphological analysis were performed. Thermogravimetry (TG) and differential scanning calorimetry (DSC) analyses showed that the thermal events attributed to excipients and films were similar, indicating the absence of physical incompatibilities between ACT and JR19. Infrared spectroscopy showed that JR19 was incorporated into ACT films. The characteristic band attributed to C≡N (2279 to 2264 cm-1) was observed in the spectra of JR19, in that of the physical mixture of JR19/ACT, and, to a lesser extent, in the spectra of JR19 incorporated into the ACT film, suggesting some interaction between JR19 and ACT. X-ray diffraction (XRD) evidenced the suppression of the crystallinity of JR19 (diffraction peaks at 8.54°, 12.80°, 14.09°, 16.08°, 18.19°, 22.65°, 23.59°, 24.53°, 25.70°, 28.16° and 30.27°2θ) after incorporation into ACT films. The mechanical tests indicated the adequate integrity of the films and their resistance to bending. The morphological characterization showed JR19 crystals along with a homogeneously distributed porous structure throughout the surface of the films with an average diameter of 21.34 µm and 22.65 µm of the films alone and of those incorporating JR19F, respectively. This study was able to characterize the ACT films incorporating JR19, showing their potential to be further developed as wound healing dressings.

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Vulvovaginal candidiasis (VVC) is a vulvar/vaginal infection that affects approximately 75% of women worldwide. The current treatment consists of antimicrobials with hepatotoxic properties and high drug interaction probabilities. Therefore, this study aimed to develop a new treatment to VVC based on micelles containing curcumin (CUR) dispersed in a ureasil-polyether (U-PEO) hybrid. The physical-chemical characterization was carried out in order to observe size, shape, crystallinity degree and particle dispersion in the formulation and was performed by dynamic light scattering (DLS), scanning electron microscopy (SEM), X-ray diffraction (XRD) and through in vitro release study. The results of DLS and SEM exhibited micelles with 35 nm, and encapsulation efficiency (EE) results demonstrated 100% of EE to CUR dispersed in the U-PEO, which was confirmed by the DRX. The release results showed that CUR loaded in U-PEO is 70% released after 10 days, which demonstrates the potential application of this material in different pharmaceutical forms (ovules and rings), and the possibility of multidose based on a single application, suggesting a higher rate of adherence.

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Leishmaniasis is one of the most neglected diseases in the world. Its most severe clinical form, called visceral, if left untreated, can be fatal. Conventional therapy is based on the use of pentavalent antimonials and includes amphotericin B (AmB) as a second-choice drug. The micellar formulation of AmB, although effective, is associated with acute and chronic toxicity. Commercially-available lipid formulations emerged to overcome such drawbacks, but their high cost limits their widespread use. Drug delivery systems such as nanoemulsions (NE) have proven ability to solubilize hydrophobic compounds, improve absorption and bioavailability, increase efficacy and reduce toxicity of encapsulated drugs. NE become even more attractive because they are inexpensive and easy to prepare. The aim of this work was to incorporate AmB in NE prepared by sonicating a mixture of surfactants, Kolliphor® HS15 (KHS15) and Brij® 52, and an oil, isopropyl myristate. NE exhibited neutral pH, conductivity values consistent with oil in water systems, spherical structures with negative Zeta potential value, monomodal size distribution and average diameter of drug-containing droplets ranging from 33 to 132 nm. AmB did not modify the thermal behavior of the system, likely due to its dispersion in the internal phase. Statistically similar antileishmanial activity of AmB-loaded NE to that of AmB micellar formulation suggests further exploring them in terms of toxicity and effectiveness against amastigotes, with the aim of offering an alternative to treat visceral leishmaniasis.

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Cellulose is among the top 5 excipients used in the pharmaceutical industry. It has been considered one of the main diluents used in conventional and modern dosage forms. Therefore, different raw materials of plant origin have been evaluated as potential alternative sources of cellulose. In this context, Opuntia ficus-indica L. Miller (palma forrageira), a plant of the cactus family that has physiological mechanisms that provide greater productivity with reduced water requirements, is an interesting and unexplored alternative for extracting cellulose. By using this source, we aim to decrease the extraction stages and increase the yields, which might result in a decreased cost for the industry and consequently for the consumer. The aim of this work was to investigate the use of Opuntia ficus-indica L. Miller as a new source for cellulose extraction, therefore providing an efficient, straight forward and low-cost method of cellulose II production. The extraction method is based on the oxidation of the lignins. The obtained cellulose was identified and characterized by spectroscopic methods (FTIR and NMR), X-ray diffraction, thermal analysis (TGA-DTG and DSC) and scanning electron microscopy. The results confirmed the identity of cellulose and its fibrous nature, which are promising characteristics for its use in the industry and a reasonable substrate for chemical modifications for the synthesis of cellulose II derivatives with different physicochemical properties that might be used in the production of drug delivery systems and biomaterials.

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Hemoglobin variants (Hb) result from mutations in globin genes, with amino acid substitution in the polypeptide chain. Among the most common structural variants are HbS, HbC, HbD and HbE. The S hemoglobin gene is a high frequency gene across America and Brazil, where it is more frequent in the Southeast and Northeast. The scope of this article is to investigate the presence of hemoglobin variants in 15 quilombos (fugitive slave communities) of Piaui. The sample was of 1,239 people and hemoglobin was screened by high-performance liquid chromatography (HPLC). A questionnaire was applied related to gender, ethnicity and consanguinity. Of the samples analyzed, 5.4% had AS sickle cell trait, while SS and SC sickle cell anemia showed a rate of 0.8%, with AC, AD and DD hemoglobin. Of the 1,069 Afro-descendants, 84 revealed hemoglobin abnormalities, 34 being male 53 being female. There were 13 consanguineous marriages among the 84 hemoglobin alterations. The study of hemoglobin variants in 15 former quilombo communities in the state of Piaui contributes to their education in health in the aspects of genetic inheritance of hemoglobin, a relevant public health issue, providing input for the implementation of the State Program of Sickle Cell Disease of Piaui.

As hemoglobinas variantes (Hb) decorrem de mutações nos genes da globina. As variantes estruturais mais frequentes são HbS, HbC, HbD e HbE. O gene da hemoglobina S tem frequência elevada na América, enquanto que no Brasil é maior no Sudeste e Nordeste. O presente artigo tem por objetivo investigar a presença de hemoglobinas variantes em 15 comunidades quilombolas do estado do Piauí. Foram analisadas 1.239 amostras, nas quais as hemoglobinas foram triadas pela cromatografia líquida de alta eficiência (HPLC). Aplicou-se questionário referente a gênero, etnia e consanguinidade das populações. Das 1.239 amostras, 5,4% apresentaram o traço falciforme AS, as doenças falciformes SS e SC apareceram em 0,8% do total, nas hemoglobinas AC, AD e DD. Das 1.069 pessoas negras, 84 apresentaram alteração das hemoglobinas; destas, 34 eram do sexo masculino e 53 do feminino. Ocorreu a presença de 13 casamentos consanguíneos dentre as 84 alterações das hemoglobinas. O estudo das hemoglobinas variantes em 15 comunidades remanescentes de quilombos do Piauí contribui para sua educação em saúde frente aos aspectos da herança genética destas proteínas, relevante questão de saúde pública, proporcionando subsídios para a implantação do Programa Estadual da Doença Falciforme do Piauí.

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Resumo As hemoglobinas variantes (Hb) decorrem de mutações nos genes da globina. As variantes estruturais mais frequentes são HbS, HbC, HbD e HbE. O gene da hemoglobina S tem frequência elevada na América, enquanto que no Brasil é maior no Sudeste e Nordeste. O presente artigo tem por objetivo investigar a presença de hemoglobinas variantes em 15 comunidades quilombolas do estado do Piauí. Foram analisadas 1.239 amostras, nas quais as hemoglobinas foram triadas pela cromatografia líquida de alta eficiência (HPLC). Aplicou-se questionário referente a gênero, etnia e consanguinidade das populações. Das 1.239 amostras, 5,4% apresentaram o traço falciforme AS, as doenças falciformes SS e SC apareceram em 0,8% do total, nas hemoglobinas AC, AD e DD. Das 1.069 pessoas negras, 84 apresentaram alteração das hemoglobinas; destas, 34 eram do sexo masculino e 53 do feminino. Ocorreu a presença de 13 casamentos consanguíneos dentre as 84 alterações das hemoglobinas. O estudo das hemoglobinas variantes em 15 comunidades remanescentes de quilombos do Piauí contribui para sua educação em saúde frente aos aspectos da herança genética destas proteínas, relevante questão de saúde pública, proporcionando subsídios para a implantação do Programa Estadual da Doença Falciforme do Piauí.

Abstract Hemoglobin variants (Hb) result from mutations in globin genes, with amino acid substitution in the polypeptide chain. Among the most common structural variants are HbS, HbC, HbD and HbE. The S hemoglobin gene is a high frequency gene across America and Brazil, where it is more frequent in the Southeast and Northeast. The scope of this article is to investigate the presence of hemoglobin variants in 15 quilombos (fugitive slave communities) of Piaui. The sample was of 1,239 people and hemoglobin was screened by high-performance liquid chromatography (HPLC). A questionnaire was applied related to gender, ethnicity and consanguinity. Of the samples analyzed, 5.4% had AS sickle cell trait, while SS and SC sickle cell anemia showed a rate of 0.8%, with AC, AD and DD hemoglobin. Of the 1,069 Afro-descendants, 84 revealed hemoglobin abnormalities, 34 being male 53 being female. There were 13 consanguineous marriages among the 84 hemoglobin alterations. The study of hemoglobin variants in 15 former quilombo communities in the state of Piaui contributes to their education in health in the aspects of genetic inheritance of hemoglobin, a relevant public health issue, providing input for the implementation of the State Program of Sickle Cell Disease of Piaui.

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O presente trabalho teve por objetivo validar métodos por espectrofotometria UV-Vis e por CLAE para a análise quantitativa de um derivado do tiofeno, o 2-[(3,4-dicloro-benzilideno)-amino]-5,6-diidro-4H-ciclopen-ta[b]tiofeno-3-carbonitrila (5CN05) e aplicá-los no doseamento da molécula contida em microemulsões, Os métodos propostos foram validados conforme a Resolução 899/2003 da Agência Nacional de Vigilância Sanitária (ANVISA), O comprimento de onda de máxima absorção do fármaco 5CN05 foi detectado em λ max= 387nm, O método espectrofotométrico validado mostrou-se seletivo, apresentando linearidade na faixa de 3 a 16 µg.mL-1, coeficiente de correlação (r) igual a 0,9998 e limites de detecção e quantificação de 0,12 µg.mL-1 e 0,41 µg.mL-1, respectivamente, Para o método CLAE, observou-se linearidade na faixa de 0,1 a 3,0 µg.mL-1, r = 0,99915, limites de detecção e quantificação de 0,07 µg.mL-1 e 0,10 µg.mL-1 respectivamente, Para ambos os métodos, os parâmetros precisão, exatidão e robustez mostraram-se adequados para o uso pretendido, As metodologias propostas podem ser seguramente aplicadas para quantificação do 5CN05 em produtos farmacêuticos como microemulsões...

This study aims to validate methods of Uv-Vis) and HPLC for quantitative determination of a thiophene derivative, 2 - [(3,4-dichloro -benzylidene)-amino] -5,6-dihydro-4H-cyclopentyl-ta [b] thiophene-3- carbonitrile referred in this study as 5CN05, and apply them to quantify the 5CN05 in microemulsions. The proposed methods were validated according to the Resolution RE 899/2003 of the National Health Surveillance Agency (ANVISA). The 5CN05 was detected by UV-Vis at λ max= 387nm. The validated UVVis UVVis method proved to be selective, showing linearity in the range of 3-16 µg.mL-1, correlation coefficient (r) of 0.9998 and limits of detection and quantification of 0.12 µg.mL-1 and 0.41 µg.mL-1 respectively. For the CLAE method the linearity was observed in the range 0.1 to 3.0 µg.mL-1, r = 0.99915, limits of detection and quantification of 0.07 µg.mL-1 and 0.10 µg.mL-1 respectively. For both UV-Vis and CLAE methods, the precision parameters, accuracy and robustness were adequate for the intended use. The proposed methodologies can be safely applied to quantify the 5CN05 in pharmaceutical microemulsions products...

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Fungal infections have become a major problem of worldwide concern. Yeasts belonging to the Candida genus and the pathogenic fungus Cryptococcus neoformans are responsible for different clinical manifestations, especially in immunocompromised patients. Antifungal therapies are currently based on a few chemotherapeutic agents that have problems related to effectiveness and resistance profiles. Microemulsions are isotropic, thermodynamically stable transparent systems of oil, water and surfactant that can improve the solubilization of lipophilic drugs. Taking into account the need for more effective and less toxic drugs along with the potential of thiophene derivatives as inhibitors of pathogenic fungi growth, this study aimed to evaluate the antifungal activity of a thiophene derivative (5CN05) embedded in a microemulsion (ME). The minimum inhibitory concentration (MIC) was determined using the microdilution method using amphotericin B as a control. The formulations tested (ME- blank and ME-5CN05) showed physico-chemical properties that would allow their use by the topical route. 5CN05 as such exhibited moderate or weak antifungal activity against Candida species (MIC = 270-540 µg.mL-1) and good activity against C. neoformans (MIC = 17 µg.mL-1). Candida species were susceptible to ME-5CN05 (70-140 µg.mL-1), but C. neoformans was much more, presenting a MIC value of 2.2 µg.mL-1. The results of this work proved promising for the pharmaceutical industry, because they suggest an alternative therapy against C. neoformans.

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Fungal infections have become a major problem of worldwide concern. Yeasts belonging to the Candida genus and the pathogenic fungus Cryptococcus neoformans are responsible for different clinical manifestations, especially in immunocompromised patients. Antifungal therapies are currently based on a few chemotherapeutic agents that have problems related to effectiveness and resistance profiles. Microemulsions are isotropic, thermodynamically stable transparent systems of oil, water and surfactant that can improve the solubilization of lipophilic drugs. Taking into account the need for more effective and less toxic drugs along with the potential of thiophene derivatives as inhibitors of pathogenic fungi growth, this study aimed to evaluate the antifungal activity of a thiophene derivative (5CN05) embedded in a microemulsion (ME). The minimum inhibitory concentration (MIC) was determined using the microdilution method using amphotericin B as a control. The formulations tested (ME- blank and ME-5CN05) showed physico-chemical properties that would allow their use by the topical route. 5CN05 as such exhibited moderate or weak antifungal activity against Candida species (MIC = 270-540 µg.mL-1) and good activity against C. neoformans (MIC = 17 µg.mL-1). Candida species were susceptible to ME-5CN05 (70-140 µg.mL-1), but C. neoformans was much more, presenting a MIC value of 2.2 µg.mL-1. The results of this work proved promising for the pharmaceutical industry, because they suggest an alternative therapy against C. neoformans.

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A exemplo do que ocorre com outros fármacos, a biodisponibilidade da anfotericina B (AmB) através da via ocular repreesenta um grande desafio para a pesquisa científica. Na verdade, a baixa biodisponibilidade apresentada por tal molécula é devido, principalmente, a presença das barreiras oculares que impedem a absorção deste fármaco para os tecidos internos. A toxicidade associada a este fármaco, assim como a sua baixa capacidade em permear a córnea íntegra também consiste em um problema associado ao seu uso clínico. Novos veículos seguros e eficazes para a liberação ocular da AmB são, portanto, necessários. As microemulsões (MEs) aparecem como um interessante sistema devido à sua transparência, estabilidade termodinâmica e favorável viscosidade. O conhecimento do processo de formação das MEs contendo AmB, assim como a compreensão de toda a sua caracterização físico-química correspondem a aspectos importantes para se determinar as condições favoráveis para que estes sistemas venham a ser empregados como colírios. Esta revisão tem como objetivo, portanto, abordar este tema enfatizando os principais aspectos relacionados com a utilização de MEs como sistemas de liberação para a AmB através da via tópica oftálmica.

As occurs with a number of drugs, the bioavailability of amphotericin B (AmB) used to treat fungal infections by the ocular route remains a great challenge to research scientists. In fact, the poor bioavailability of AmB is due mainly to the corneal barrier, which leads to a precorneal loss and consequent decrease in the absorption of this drug into the intraocular tissues. The toxicity associated with this molecule, together with its poor ability to penetrate the intact corneal epithelium, also represents a major drawback to its clinical use. New effective and safe drug vehicles for ocular delivery of AmB are therefore urgently needed. Microemulsions (MEs) seem to be an interesting system, owing to their transparent appearance, thermodynamic stability and favorable viscosity. Knowledge of the process of formation of AmB-containing MEs, as well as a good understanding of the physical chemistry of such systems, would provide reliable information on the best conditions for the use of these systems as eye drops. The goal of this research was thus to make an approach to this subject by reviewing the main studies on the use of MEs as delivery systems for AmB in topical eye treatment.

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