Design and evaluation of dry-coated tablets for colonic delivery of diclofenac sodium

A colonic drug delivery system is required to protect a drug during its transit through the upper gastro-intestinal tract and allow its release in the colon. The aim of this study was the preparation of dry-coated tablets designed for colonic release of the model drug Diclofenac sodium (DS). The system consists of a drug-pectine (PC) mixture as the core and hydroxypropylmethylcellulose (HPMC) alone or mixed in different ratios with poly(ε-caprolactone) (CL) as the coat layer

Cyclopentenyl ethylamines active on CNS

Two new cyclopentenylethylamines were prepared and were submitted to a pharmacological screening together with some others previously described and now reprepared. All compounds exhibited different degrees of depressive activity on CNS and good analgesic activity. Compound 5, bearing a phenyl group on the carbon atom to which the amino group is connected, appears rather interesting being the most active as analgesic and the least toxic. Compounds 2 and 3 are able to antagonize in a certain degree lethal doses of physostigmine and also, respectively, of pentylenetetrazole and strychnine

Study of hydrogels based on polyacrilamide as new controlled release dosage forms produced by frontal polymerization

The work purpose was the evaluation of the potential application of the Frontal Polymerization (FP) technique as a new method for the preparation of controlled release dosage forms based on polyacrilamide, in which the drug loading and the polymer preparation occur at the same time

Synthesis and pharmacological activity of 4-carbamoyl-6-beta-thienyl-4,5-dihydropyridazin-3-(2H)ones

A new series of 4-carbamoyl-6-beta-thienyl-4,5-dihydropyridazin-3-(2H)ones 4a-g have been synthesized and tested for their anti-inflammatory and analgesic properties. Among the tested compounds, only 4f at 1 mmole/Kg showed antiinflammatory activity that was comparable with that of indomethacin (5 mg/Kg) though of shorter duration. Compounds 4a, 4e and especially 4g at 0.2 mmoles/Kg displayed relevant analgesic activity, 4g being the most potent derivative in the writhing test. Compounds 4c and 4g were found to possess analgesic activity also in the hot plate test

Antispasmodic activity of tert-aminoalkylderivatives of 3-benzyl-, 3-benzylaza- and 3-benzyldiazaquinoxalinones

Tert-aminoalkylderivatives of quinoxalin-2-ones, aza- and diazaquinoxalin-2-ones bearing in position 3 a benzyl group were assayed to evaluate the antispasmodic activity. The tested compounds exhibited moderate aspecific antispastic properties that do not warrant further investigation

Pyridazine <i>N</i>-oxides. III Synthesis and <i>in vitro</i> antimicrobial properties of N-oxide derivatives based on tricyclic indeno[2,1-c]pyridazine and benzo[<i>f</i>]cinnoline systems

A number of 9H-indeno[2,1-c]pyridazine N-oxides (3a - c) and benzo[f]cinnoline N-oxides (4,5a - c) have been synthesized and tested for antimicrobial activity. All new products were inactive against Gram negative bacteria and fungi. In contrast, among the compounds synthesized, 3b, 4b and 5b showed a moderate activity against Gram positive Staphylococcus aureus and Staphylococcus epidermidis. Of the present series, the 9-nitro-benzo[f]cinnoline N-oxide 5b possessed the highest activity especially against Trichomonas vaginalis (MIC = 3.9 g/ml)

Cyclopenta[e] [1,5] benzodiazepin-10 (9H)-one derivatives as CNS depressant agents

A series of dialkylaminoalkyl derivatives of cyclopenta[e] [1,5] benzodiazepin-10(9H)-one (E1-4) and its 6-chloro derivative (E5-8) was prepared to evaluate their CNS activity in comparison with that of isosteric pyridodiazepinones (A1-4) previously described. The results of the pharmacological screening show a significant depressant activity more remarkable in 6-chloro derivatives, which also revealed a high and lasting analgesic activity. The replacement of pyridine with benzene nucleus did not show any significant or homogeneous activity variation

Nasal administration of Carbamazepine using chitosan microspheres: <i>in vitro/in vivo</i> studies

The nasal route is used both for local therapies and, more recently, for the systemic administration of drugs, as well as for the delivery of peptides and vaccines. In this study the nasal administration of Carbamazepine (CBZ) has been studied using microspheres constituted by chitosan hydrochloride (CH) or chitosan glutamate (CG). Blank microspheres were also prepared as a comparison. The microspheres were produced using a spray-drying technique and characterized in terms of morphology (scanning electron microscopy, SEM), drug content, particle size (laser diffraction method) and thermal behaviour (differential scanning calorimetry, DSC). In vitro drug release studies were performed in phosphate buffer (pH 7.0). In vivo tests were carried out in sheep using the microparticles containing chitosan glutamate, chosen on the basis of the results of in vitro studies. The results were compared to those obtained after the nasal administration of CBZ (raw material) alone. For the evaluation of in vivo data statistical analysis was carried out using the unpaired t-test. Spray-drying was a good technique of preparation of CBZ-loaded microspheres. The loading of the drug into the polymeric network always led to an increase in the dissolution rate compared to CBZ raw material. The microspheres obtained using chitosan glutamate had the best behaviour both in vitro and in vivo. They increased the drug concentration in the serum when compared to the nasal administration of the pure drug (Cmax 800 and 25 ng/ml for microspheres and pure drug, respectively). The results obtained indicate that the loading of CBZ in chitosan glutamate microspheres increases the amount of the drug absorbed through the nose