Person: Cazorla Luna, Raúl
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First Name
Raúl
Last Name
Cazorla Luna
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Farmacia
Department
Farmacia Galénica y Tecnología Alimentaria
Area
Farmacia y Tecnología Farmaceútica
Identifiers
7 results
Search Results
Now showing 1 - 7 of 7
Item Smart Freeze-Dried Bigels for the Prevention of the Sexual Transmission of HIV by Accelerating the Vaginal Release of Tenofovir during Intercourse(Pharmaceutics, 2019) Martín Illana, Araceli; Notario Pérez, Fernando; Cazorla Luna, Raúl; Ruiz Caro, Roberto; Veiga Ochoa, María DoloresSub-Saharan African women are still at risk from the human immunodeficiency virus (HIV), and sex with men is the main route of transmission. Vaginal formulations containing antiretroviral drugs are promising tools to give women the power to protect themselves. The aim of this work was to obtain freeze-dried bigels containing pectin, chitosan, or hypromellose for the vaginal controlled release of Tenofovir, which is accelerated in the presence of semen. Nine batches of bigels were formulated using di_erent proportions of these polymers in the hydrogel (1, 2, and 3% w/w). The bigels obtained were freeze-dried and then underwent hardness and deformability, mucoadhesion, swelling, and drug release tests, the last two in simulated vaginal fluid (SVF) and SVF/simulated seminal fluid (SSF) mixture. The formulation containing 3% pectin (fd3P) has the highest values for hardness, resistance to deformation, and good mucoadhesivity. Its swelling is conditioned by the pH of the medium, which is responsive to the controlled release of Tenofovir in SVF, with the fastest release in the SVF/SSF mixture. fd3P would be an interesting smart microbicidal system to allow faster reléase of Tenofovir in the presence of semen, and thus increase women’s ability to protect themselves from the sexual transmission of HIV.Item Chitosan-Based Mucoadhesive Vaginal Tablets for Controlled Release of the Anti-HIV Drug Tenofovir(Pharmaceutics, 2019) Cazorla Luna, Raúl; Notario Pérez, Fernando; Martín Illana, Araceli; Ruiz Caro, Roberto; Tamayo, Aitana; Rubio, Juan; Veiga Ochoa, María DoloresVaginal microbicides have the potential to give women at high risk of contracting HIV the option of self-protection by preventing the sexual transmission of the virus. In this paper, mucoadhesive vaginal tablets based on chitosan, alone and in combination with pectin and locust bean gum, were developed for the sustained release of tenofovir (an antiretroviral drug). The formulations were placed in simulant vaginal fluid (SVF) to swell, and Hg porosity and SEM microscopy were used for the microstructural characterization of the swelling witnesses. The results show that the association of pectin and chitosan generated polyelectrolyte complexes and produced a robust system able to maintain its structure during the swelling process, when small pores are formed. Drug reléase and bovine vaginal mucoadhesion studies were performed in SVF showing that tenofovir-controlled dissolution profiles and adhesion to the mucosa were conditioned by the swelling processes of the polymer/s in each formulation. Tablets based on chitosan/pectin have the most homogeneous tenofovir dissolution profiles and last up to 96 h, remaining attached to the vaginal mucosa for the same period. These formulations can therefore be considered a good option for the self-protection of women from the sexual transmission of HIV.Item Formulaciones de administración vaginal para la prevención del herpes genital(2015) Cazorla Luna, Raúl; Veiga Ochoa, María DoloresEl herpes genital, producido por el Virus Herpes Simplex (VHS) tipo 2, es una de las enfermedades de transmisión sexual más extendida a nivel mundial. La ineficacia de los sistemas actuales de prevención hace necesario desarrollar nuevas formulaciones, siendo las más estudiadas aquellas que permanecen adheridas en la zona de aplicación y que permitan una liberación sostenida de agentes microbicidas. Por ello, el objetivo de este trabajo es realizar una revisión bibliográfica para comparar los distintos polímeros empleados como excipientes en dichas formulaciones así como la evaluación de los métodos de caracterización in vitro y ex vivo de las mismas. Los polímeros empleados frecuentemente en formulaciones mucoadhesivas vaginales pueden ser de origen natural, sintéticos y semisintéticos. Estos excipientes se emplean con el fin de conseguir formulaciones mucoadhesivas que además modulen la liberación de agentes microbicidas a nivel vaginal, y estas propiedades van a ser directamente dependientes de las características del polímero utilizado. Los sistemas preparados se someten a varios ensayos in vitro que permitan caracterizar sus propiedades. Así, el hinchamiento se evalúa con el fin de determinar las propiedades estructurales del polímero en la formulación, lo cual condiciona los dos estudios siguientes; los de mucoadhesión y los de cesión, que permiten comprobar que la formulación permanece en la zona de aplicación el tiempo necesario y que la cesión del agente microbicida es constante durante el periodo de permanencia en la mucosa.Item Tenofovir Hot-Melt Granulation using Gelucire® to Develop Sustained-Release Vaginal Systems for Weekly Protection against Sexual Transmission of HIV(Pharmaceutics, 2019) Notario Pérez, Fernando; Cazorla Luna, Raúl; Martín Illana, Araceli; Ruiz Caro, Roberto; Peña López, Juan; Veiga Ochoa, María DoloresHot-melt granulation is a technique used to obtain granules by dispersing a drug in polymers at a high temperature. Tenofovir, an antiretroviral drug with proven activity as a vaginal microbicide, was dispersed in melted Gelucire® (or a mixture of different Gelucire®) to obtain drug-loaded granules. Studies performed on the granules proved that the drug is not altered in the hot-melt granulation process. The granules obtained were included in a matrix formed by the hydrophilic polymers hydroxypropylmethylcellulose and chitosan to obtain vaginal tablets that combine different mechanisms of controlled release: The Gelucire® needs to soften to allow the release of the Tenofovir, and the hydrophilic polymers must form a gel so the drug can diffuse through it. The studies performed with the tablets were swelling behavior, Tenofovir release, and ex vivo mucoadhesion. The tablets containing granules obtained with Tenofovir and Gelucire® 43/01 in a ratio of 1:2 in a matrix formed by hydroxypropylmethylcellulose and chitosan in a ratio of 1.9:1 were selected as the optimal formulation, since they release Tenofovir in a sustained manner over 216h and remain attached to the vaginal mucosa throughout. A weekly administration of these tablets would therefore offer women protection against the sexual transmission of HIV.Item Physical activity effects on the individual alpha peak frequency of older adults with and without genetic risk factors for Alzheimer’s Disease: A MEG study(Clinical Neurophysiology, 2018) De Frutos Lucas, Jaisalmer; López Sanz, David; Zuluaga Arias, María Del Pilar; Rodríguez Rojo, Inmaculada Concepción; Cazorla Luna, Raúl; López García, María Eugenia; Delgado Losada, María Luisa; Marcos Dolado, Alberto; Barabash Bustelo, Ana; López Sánchez, Ramón; Maestu Unturbe, Fernando; Fernández Lucas, Alberto AmableObjective Since a cure for Alzheimer’s Disease (AD) is yet to be discovered, attention has shifted towards prevention. Physical activity (PA) emerged as a notorious lifestyle factor that could influence brain structure and function. The individual alpha peak frequency (IAPF) is a measure that summarizes the spectral content of brain signals and has been proven to be sensitive to both AD pathology and PA interventions. Therefore, our goal was to unravel whether chronic PA modulates IAPF and if APOE ɛ4 carriage moderates this relationship. Methods We analyzed 4-minutes of resting-state magnetoencephalographic recordings from 100 healthy elders that provided self-reported measures of PA, and the IAPF was calculated. Results We found that IAPF was negatively influenced by age and APOE and positively influenced by PA. The effect of PA on IAPF only remained significant for the ɛ4 non-carriers group. Conclusions PA is positively associated to higher IAPF in healthy older adults and could potentially act as a protective factor against cognitive decline. Nevertheless, such effect is non-significant among elders who are more vulnerable to developing AD due to their genetic carriage. Significance This investigation offers the first neurophysiological evidences on the combined effects of APOE genotype and PA in healthy elders.Item Dapivirine Bioadhesive Vaginal Tablets Based on Natural Polymers for the Prevention of Sexual Transmission of HIV(Polymers, 2019) Cazorla Luna, Raúl; Martín Illana, Araceli; Notario Pérez, Fernando; Bedoya Del Olmo, Luis Miguel; Ruiz Caro, Roberto; Bermejo Benito, Paulina; Veiga Ochoa, María DoloresYoung sub-Saharan women are a group that is vulnerable to the sexual transmission of HIV. Pre-exposure prophylaxis through vaginal microbicides could provide them an option for self-protection. Dapivirine has been demonstrated to have topical inhibitory effects in HIV, and to provide protection against the sexual transmission of this virus. This paper reports on the studies into swelling behaviour, bioadhesion and release carried out on dapivirine tablets based on chitosan, locust bean gum and pectin, to select the most suitable formulation. The modified simulated vaginal fluid led to a high solubility of dapivirine and allowed the dapivirine release profiles to be characterized in sink conditions; this aqueous medium is an alternative to organic solvents, which are not a realistic option when evaluating systems whose behaviour varies in aqueous and organic media. Of the formulations evaluated, dapivirine/pectin tablets containing 290 mg of polymer and 30 mg of dapivirine present the most moderate swelling, making them the most comfortable dosage forms. Their high bioadhesive capacity would also allow the formulation to remain in the action zone and release the drug in a sustained manner, pointing to this formulation as the most promising candidate for future evaluations of vaginal microbicides for the prevention of HIV.Item Influence of Chitosan Swelling Behaviour on Controlled Release of Tenofovir from Mucoadhesive Vaginal Systems for Prevention of Sexual Transmission of HIV(Marine Drugs, 2017) Notario Pérez, Fernando; Martín Illana, Araceli; Cazorla Luna, Raúl; Ruiz Caro, Roberto; Bedoya Del Olmo, Luis Miguel; Tamayo, Aitana; Rubio, Juan; Veiga Ochoa, María DoloresThe main challenges facing efforts to prevent the transmission of human immunodeficiency virus (HIV) are the lack of access to sexual education services and sexual violence against young women and girls. Vaginal formulations for the prevention of sexually transmitted infections are currently gaining importance in drug development. Vaginal mucoadhesive tablets can be developed by including natural polymers that have good binding capacity with mucosal tissues, such as chitosan or guar gum, semisynthetic polymers such as hydroxypropylmethyl cellulose, or synthetic polymers such as Eudragit® RS. This paper assesses the potential of chitosan for the development of sustained-release vaginal tablets of Tenofovir and compares it with different polymers. The parameters assessed were the permanence time of the bioadhesion—determined ex vivo using bovine vaginal mucosa as substrate—the drug release profiles from the formulation to the medium (simulated vaginal fluid), and swelling profiles in the same medium. Chitosan can be said to allow the manufacture of tablets that remain adhered to the vaginal mucosa and release the drug in a sustained way, with low toxicity and moderate swelling that ensures the comfort of the patient and may be useful for the prevention of sexual transmission of HIV.