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The aim of this work was to study the solubility in supercritical CO2 of the hydrated phase of three model drugs, namely theophylline, carbamazepine, and diclofenac sodium, in comparison with the respective anhydrous form. Possible solid-state modifications, stemming from the interaction with supercritical CO2, were investigated by differential scanning calorimetry, thermogravimetric analysis, hot stage microscopy, Fourier Transform infrared spectroscopy and Karl-Fischer titrimetry. It was found that all three pharmaceutical hydrates exhibited higher solubility in supercritical CO2 than the relevant anhydrous phases. In the case of theophylline monohydrate, the instability of the crystal phase at the experimental temperature adopted has been evidenced. Diclofenac sodium tetrahydrate represents a peculiar case of chemical interaction with the acid supercritical fluid, mediated by crystal water. [ABSTRACT FROM AUTHOR]

Aim of this work was to investigate the solid-state characteristics of micronized acetylsalicylic acid (ASA), produced by rapid expansion of a supercritical carbon dioxide solution (RESS) and to assess whether a correlation could be found between process parameters and solid-state characteristics. Drug solubility in supercritical CO2 was first assessed under various pressure and temperature conditions. DSC, FT-IR, PXRD, SEM, laser light scattering and HPLC were used to characterise the solid phases produced by the RESS. The obtained particles were crystalline, with spectroscopical and diffractometrical pattern overlapping those of the starting available product. However, a strong reduction of particle size was obtained, linearly correlated to pressure imposed during the RESS process, while temperature did not seem to have a major effect. Similar influence of pressure was observed on the final melting temperature of the micronized ASA. The application of a mathematical model allowed to conclude that the melting temperature depression of RESS-prepared ASA powders can be attributed to the decrease of particle dimension rather than to the formation of different solid phases or impurities. [ABSTRACT FROM AUTHOR]

The thermal behaviour of Diclofenac was investigated using Differential Scanning Calorimetry, Hot Stage Microscopy, and Thermogravimetric Analysis. A discrepancy was observed between the melting point values recorded under dynamic flow of either dry nitrogen (180°C) or air (160°C). By means of High Performance Liquid Chromatography/Mass Spectrometric analyses, it has been possible to ascribe this difference in melting points to the formation of three degradation products as a result of intramolecular cyclization and condensation reactions during the heating process in an oxidative atmosphere. [ABSTRACT FROM AUTHOR]

With the currently used surgical procedures, surgical correction of extreme forms of high undescended testes is associated with an atrophy rate of 10% to 30%. In this experimental study in two groups of Sprague-Dawley rats of pubescent age, we examined whether fixation (pexy) of an omental flap on the testis (omentotesticulopexy=OMTX) permits preservation of the viability of the parenchyma. A left-sided OMTX was performed in group 1 with the animals under general anaesthesia. An omental flap was prepared. The tunica albuginea of the testis planned for OMTX was pierced with a needle (26 × 23 G) within an area with a diameter of 1 cm; a puncture distance of 2 mm was used. The omental flap was then fixed using absorbable monofilament 6-0 interrupted sutures. Six weeks later the spermatic vessel was transected at this site. The right testis was left untouched throughout the procedure; it remained in situ. In group 2 only the spermatic vessel on the left side was severed. The right testis was not manipulated and remained in situ. After a total of 10 weeks both testes were removed from all rats and fixed in formalin. Standardised haematoxylin and eosin staining was performed and histological sections were obtained. The size of the testicles, Leydig-cell count, viability, and calcified areas within the tissue were determined for all testicles. Student's t-test was used for statistical evaluation. The study showed that OMTX leads to neovascularisation in the area of fixation and that viability can be preserved within this area. [ABSTRACT FROM AUTHOR]

A new technique of umbilicoplasty in neonates who underwent primary omphalocele repair is described and illustrated. The procedure resulted in a nearly-normal appearance of the umbilicus. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the solubility in supercritical CO2 of the hydrated phase of three model drugs, namely theophylline, carbamazepine, and diclofenac sodium, in comparison with the respective anhydrous form. Possible solid-state modifications, stemming from the interaction with supercritical CO2, were investigated by differential scanning calorimetry, thermogravimetric analysis, hot stage microscopy, Fourier Transform infrared spectroscopy and Karl-Fischer titrimetry. It was found that all three pharmaceutical hydrates exhibited higher solubility in supercritical CO2 than the relevant anhydrous phases. In the case of theophylline monohydrate, the instability of the crystal phase at the experimental temperature adopted has been evidenced. Diclofenac sodium tetrahydrate represents a peculiar case of chemical interaction with the acid supercritical fluid, mediated by crystal water. [ABSTRACT FROM AUTHOR]