Ten steps towards a safe and feasible total laparoscopic hysterectomy.

OBJECTIVE: To contribute to the training of specialists by describing in a systematic and detailed way the ten steps to perform a safe and feasible Total Laparoscopic Hysterectomy (HTL). METHOD: The detailed description of the steps of the HTL intends that this procedure can be safely and effectively reproduced. RESULTS: By clearly knowing the steps of HTL, it is possible to favor minimally invasive routes so that patients benefit from its multiple proven benefits. CONCLUSIONS: The benefits of minimally invasive routes for performing a hysterectomy have already been demonstrated in the literature. It is particularly important that specialists are familiar with these techniques and that groups standardize the procedure so that more patients can safely undergo and benefit from the laparoscopic approach.

OBJETIVO: Contribuir a la formación de los especialistas describiendo de manera sistemática y pormenorizada los diez pasos para realizar una histerectomía total por laparoscopia (HTL) segura y reproducible. MÉTODO: La descripción detallada de los pasos de la HTL pretende que este procedimiento pueda ser reproducido de manera segura y efectiva. RESULTADOS: Al conocer claramente los pasos de la HTL es posible favorecer las rutas de mínima invasión para que las pacientes se beneficien de sus múltiples beneficios demostrados. CONCLUSIONES: Los beneficios de las rutas mínimamente invasivas para la realización de una histerectomía ya han sido demostrados en la literatura. En muy importante que los especialistas estén familiarizados con estas técnicas y que los grupos estandaricen el procedimiento para que más pacientes puedan ser intervenidas de manera segura y se beneficien de la vía laparoscópica.

Study of In Vitro and In Vivo Carbamazepine Release from Coarse and Nanometric Pharmaceutical Emulsions Obtained via Ultra-High-Pressure Homogenization.

In the past decade, pharmaceutical nanotechnology has proven to be a promising alternative for improving the physicochemical and biopharmaceutical features for conventional pharmaceutical drug formulations. The goal of this study was to develop, characterize, and evaluate the in vitro and in vivo release of the model drug carbamazepine (CBZ) from two emulsified formulations with different droplet sizes (coarse and nanometric). Briefly, oil-in-water emulsions were developed using (i) Sacha inchi oil, ultrapure water, TweenTM 80, and SpanTM 80 as surfactants, (ii) methyl-paraben and propyl-paraben as preservatives, and (iii) CBZ as a nonpolar model drug. The coarse and nanometric emulsions were prepared by rotor-stator dispersion and ultra-high-pressure homogenization (UHPH), respectively. The in vitro drug release studies were conducted by dialysis, whereas the in vivo drug release was evaluated in New Zealand breed rabbits. The results showed that nanoemulsions were physically more stable than coarse emulsions, and that CBZ had a very low release for in vitro determination (<2%), and a release of 20% in the in vivo study. However, it was found that nanoemulsions could significantly increase drug absorption time from 12 h to 45 min.

Relationship between Degree of Polymeric Ionisation and Hydrolytic Degradation of Eudragit® E Polymers under Extreme Acid Conditions.

The commercial copolymers Eudragit® E 100 and Eudragit® PO are widely used materials in the pharmaceutical field as coating systems. Such materials derived from amino-methacrylate groups under acidulated conditions may acquire an ionisable fraction or undergo hydrolytic degradation of the polymeric structure. This work focused on establishing the chemical, physical, and surface changes of two reprocessed polymeric materials, here named as EuCl-E-100 and EuCl-E-PO, which were obtained from the commercial Eudragit® E 100 and Eudragit® E PO, respectively. The commercial materials were exposed to extreme acid conditions, where the polymers were solubilised and subsequently dried by the refractance window method. The materials obtained were chemically characterised by potentiometric titration, nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR) in one and two dimensions (COSY, HSQC, and HMBC), infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. Changes in the physical properties of the materials were evaluated through studies of flowability, compactability, and their ability to gain and lose humidity. Surface thermodynamic studies were carried out through contact angle measurements using the sessile drop method. The results showed that the processed polymeric materials acquired a substantial degree of ionisation without undergoing hydrolysis of the esterified groups. Furthermore, such changes improved the flow characteristics of the material and the solubility in aqueous media at pH > 5, while also maintaining the hydrophobicity degree of the polymeric surface.

Effect of the Surface Hydrophobicity Degree on the In Vitro Release of Polar and Non-Polar Drugs from Polyelectrolyte Matrix Tablets.

This work is the continuation of a series of studies focused on establishing the relationship between the surface thermodynamic properties of polyelectrolyte matrix tablets and drug release mechanisms. In this case, two model drugs with different polarity features, such as carbamazepine (non-polar) and metoprolol succinate (polar) were used in combination with polymeric material hydroxypropyl-methyl cellulose (HPMC) and two polyelectrolytes derived from maleic anhydride corresponding to the sodium salts of poly(maleic acid-alt-ethylene) and poly(maleic acid-alt-octadecene) named PAM-0Na and PAM-18Na, respectively. The polymers were obtained and characterized as reported previously. Surface studies were performed by the sessile drop method, whilst the surface free energy was determined through Owens, Wendt, Rable and Kaeble (OWRK) semi-empirical model. By contrast, the drug release studies were performed by in vitro dissolution tests, where data were analyzed through dissolution efficiency. The results showed that, depending on the drug polarity, type and polymer proportion, surface properties and drug release processes are significantly affected.

Relationship between Surface Properties and In Vitro Drug Release from Compressed Matrix Containing Polymeric Materials with Different Hydrophobicity Degrees.

This work is the continuation of a study focused on establishing relations between surface thermodynamic properties and in vitro release mechanisms using a model drug (ampicillin trihydrate), besides analyzing the granulometric properties of new polymeric materials and thus establishing the potential to be used in the pharmaceutical field as modified delivery excipients. To do this, we used copolymeric materials derived from maleic anhydride with decreasing polarity corresponding to poly(isobutylene-alt-maleic acid) (hydrophilic), sodium salt of poly(maleic acid-alt-octadecene) (amphiphilic), poly(maleic anhydride-alt-octadecene) (hydrophobic) and the reference polymer hydroxyl-propyl-methyl-cellulose (HPMC). Each material alone and in blends underwent spectroscopic characterization by FTIR, thermal characterization by DSC and granulometric characterization using flow and compaction tests. Each tablet was prepared at different polymer ratios of 0%, 10%, 20%, 30% and 40%, and the surface properties were determined, including the roughness by micro-visualization, contact angle and water absorption rate by the sessile drop method and obtaining Wadh and surface free energy (SFE) using the semi-empirical models of Young-Dupré and  Owens-Wendt-Rabel-Käelbe (OWRK), respectively. Dissolution profiles were determined simulating physiological conditions in vitro, where the kinetic models of order-zero, order-one, Higuchi and Korsmeyer-Peppas were evaluated. The results showed a strong relationship between the proportion and nature of the polymer to the surface thermodynamic properties and kinetic release mechanism.