Short-Course Radiotherapy versus Long-Course Radio-Chemotherapy as Neoadjuvant Treatment for Locally Advanced Rectal Cancer: Meta-Analysis from a Toxicity Perspective.

Neoadjuvant treatment has become the standard of care for locally advanced rectal cancer for many years. Several neoadjuvant therapeutic options are currently used, the most common being conventionally fractionated radiotherapy (or long-course radiotherapy) administered concomitantly with chemotherapy and hypofractionated radiotherapy (or short-course radiotherapy). This meta-analysis will give a better overview of the results of several studies that compare long-course radio-chemotherapy with short-course radiotherapy, emphasizing on the severe acute and late toxicities and the postoperative results of the analyzed studies. After identification, analysis and verification of eligibility criteria, eight studies were included in the meta-analysis. The methodological quality of the selected studies was assessed using the classic Oxford quality grading system (Jadad scale). The results obtained in this meta-analysis shows us that we can safely use both short-course radiotherapy and long-course radio-chemotherapy as neoadjuvant treatment for locally advanced rectal cancer, without significant differences regarding to severe acute or late toxicities, positive resection margins R+ or the number of local pelvic relapses at three years.

Synthesis and characterization of some cellulose/chondroitin sulphate hydrogels and their evaluation as carriers for drug delivery.

Mixed hydrogels based on natural, biodegradable and biocompatible polysaccharides, such as cellulose (C) and chondroitin sulphate (CS) in various mixing ratios were prepared by a crosslinking technique and characterized by swelling behaviour, FTIR spectroscopy, scanning electron microscopy, toxicity and biocompatibility tests. The mixed cellulose/chondroitin sulphate hydrogels have been loaded with 7-[2-nitroxiacetyl-oxy-3-(4-acetyl-amino-phenoxy)-propyl]-8-morpholino-1,3-dimethyl-xanthine, a novel nitric oxide donor compound with a lower toxicity and a higher anti-inflammatory activity than its parent molecules, paracetamol and theophylline. Swelling and release kinetics have been also studied. It has been established that an increase of CS content in hydrogels composition leads to a higher swelling ratio for all formulations and to a decreased released amount of nitric oxide donor compound. It has been found that the swelling occurs by an anomalous swelling mechanism, while the release of nitric oxide donor compound follows a diffusion controlled mechanism.

In vitro and in vivo theophylline release from cellulose/chondroitin sulfate hydrogels.

In vitro and in vivo release of the theophylline, loaded in mixed polysaccharidic cellulose/chondroitin sulfate (C/CS) hydrogels has been evaluated. The C/CS hydrogels in various mixing ratios obtained by a crosslinking technique were supplementary characterized by swelling studies in a pH 2.2 acidic solution at 37 °C, simulating the gastrointestinal medium, as in vivo theophylline delivery was done by oral administration. The hydrogels loading degree with theophylline was evaluated by near infrared chemical imaging (NIR-CI) technique and confirmed also by FT-IR spectroscopy. Based on PLS-DA (partial least squares-discriminate analysis) prediction, the drug loading was found up to 92.5%. The in vitro release profiles of theophylline from C/CS hydrogels showed that an increase of chondroitin sulfate leads to a decreased theophylline percent released, increased half release time and time to reach maximum percent released. During in vivo test, the raw theophylline was rapidly, absorbed, distributed, and eliminated. Comparatively with raw drug administration, the t1/2 and AUC0-72 value were 4 times higher for theophylline loaded into 50/50 C/CS hydrogel. A good in vitro-in vivo correlation was found. A retarded release, controlled by CS content can be achieved by using mixed hydrogels as carriers.

In vitro evaluation of ketoprofen controlled release from various formulations.

UNLABELLED: The aim of this study is to investigate the potential utility of some hydrogels, based on chitosan, chitosan modified with phthalic anhydride and 75/25 poly(N-isopropyl acrylamide)/alginate, for preparing drug release systems containing ketoprofen, as model drug. MATERIAL AND METHOD: The in vitro release profiles and swelling studies were done in ethanol medium, where the studied drug presents high solubility, at 25 degrees C (room temperature). The ketoprofen release was observed by monitoring the absorbance at max = 254 nm as a function of time. RESULTS: The experimental results indicated that the smallest amount of drug was released from chitosan matrices, appreciatively 31%. CONCLUSIONS: The composition of hydrogels had an important effect on ketoprofen release.