Disintegration propensity of tablets evaluated by means of disintegrating force kinetics.

The aim of this work was to measure the disintegrating force concomitantly with tablet disintegration, in order to evaluate the disintegration propensity of tablets. Disintegration and dissolution were measured on tablets containing two poorly soluble drugs (diclofenac sodium or ketoprofen), including different percentages of two disintegrants (Explotab or Ac-Di-Sol). Because of the experimental setup, the disintegrating force measured was the result of the force generated by disintegrant swelling and dissipated by tablet disintegration.

High molecular weight polyethylene oxides (PEOs) as an alternative to HPMC in controlled release dosage forms.

High molecular weight polyethylene oxides (PEOs) have recently been proposed as an alternative to hydroxypropylmethylcellulose (HPMC) in controlled release matrix tablets. In this study, we compared the performance of PEO and HPMC polymers when employed in the Geomatrix technology, a versatile, well-known method to achieve extended release of drugs at a constant rate. Four core formulations were prepared, containing a soluble drug (diltiazem) and, alternatively, PEO or HPMC of two different viscosity grades.

Model for estimation of human exposure to copper in drinking water.

A model denominated Consumption Habit Exposure Model, (CHEM), was developed for the calculation of human individual acute and chronic exposure to copper in drinking water. The model can estimate daily exposure of individuals as well as the maximum concentration of copper which individuals ingest during a 24-h period. The CHEM model requires carrying out a water consumption habit questionnaire and measuring the minimum and maximum concentration of copper in homes, as well as minimum and random copper concentration at work and study places.

Formulation of biphasic release tablets containing slightly soluble drugs.

A new biphasic release system for slightly soluble drugs has been proposed. To enhance the dissolution rate, the drug was milled with a superdisintegrant. Then, double-layer tablets were prepared.

Effect of bacterial antigen lysate on IgG and IgA levels in children with recurrent infections and hypogammaglobulinemia.

To evaluate the effect of bacterial antigen lysate on serum immunoglobulin (Ig) levels, we studied 14 children with recurrent infections and hypogammaglobulinemia (IgG and IgA levels below 2 standard deviations for age). Patients were treated for a 60-90 day period with OM-85 BV and reevaluated both clinically and by measuring serum Ig levels at the end of follow-up. The control group consisted of 10 children with recurrent infections who received a placebo.

Nicotinic acetylcholine receptors assembled from the alpha7 and beta3 subunits.

Intracellular recordings were performed in voltage-clamped Xenopus oocytes upon injection with a mixture of cDNAs encoding the beta3 and mutant alpha7 (L247Talpha7) neuronal nicotinic acetylcholine receptor (nAChR) subunits. The expressed receptors maintained sensitivity to methyllycaconitine and to alpha-bungarotoxin but exhibited a functional profile strikingly different from that of the homomeric L247Talpha7 receptor. The heteromeric L247Talpha7beta3 nAChR had a lower apparent affinity and a faster rate of desensitization than L247Talpha7 nAChR, exhibited nonlinearity in the I-V relationship, and was inhibited by 5-hydroxytryptamine, much like wild type alpha7 (WTalpha7) nAChR.

Influence of the moisture on the performance of a new dry powder inhaler.

An accelerated stability test was carried out on two prototypes of a new dry powder inhaler (DPI) to verify the influence of moisture uptake on the performance of the device. The prototypes were stored at 40 degrees C and 75% relative humidity (RH) for different storage times and their performance was assessed in terms of emitted dose and respirable fraction (Twin Impinger). At the same time intervals, the water content of the powder contained in the drug reservoir was evaluated using Karl Fischer's method.

Selective effects of a 4-oxystilbene derivative on wild and mutant neuronal chick alpha7 nicotinic receptor.

1. We assessed the pharmacological activity of triethyl-(beta-4-stilbenoxy-ethyl) ammonium (MG624), a drug that is active on neuronal nicotinic receptors (nicotinic AChR). Experiments on the major nicotinic AChR subtypes present in chick brain, showed that it inhibits the binding of [125I]-alphaBungarotoxin (alphaBgtx) to the alpha7 subtype, and that of [3H]-epibatidine (Epi) to the alpha4beta2 subtype, with Ki values of respectively 106 nM and 84 microM.

Procedure for analysis of radium in freshwaters by adsorption on basic lead rhodizonate.

Radium analysis is carried out by batch adsorption from natural waters on basic lead rhodizonate supported on charcoal, LERHO, starting from 2-L samples. 133Ba is added to allow the measurement of the overall chemical yield by gamma counting. Radium is recovered with a few milliliters of 1.

Pneumonia due to Leptospira spp.: results of an epidemiological and clinical study.

Objective: To evaluate the prevalence of Leptospira spp. infections in a population of in- and out-patients with community acquired pneumonia (CAP) and the incidence of leptospiral pneumonia.

Design And Results: Of 176 patients infected with CAP who were evaluated for the presence of Leptospira spp.

4-Oxystilbene compounds are selective ligands for neuronal nicotinic alphaBungarotoxin receptors.

1. Starting from the structure of an old 4-oxystilbene derivate with ganglioplegic activity (MG624), we synthesized two further derivates (F2 and F3) and two stereoisomers of F3 (F3A and F3B), and studied their selective effect on neuronal nicotinic acetylcholine receptor (AChR) subtypes. 2.

Effects of Zn2+ on wild and mutant neuronal alpha7 nicotinic receptors.

Zn2+ is a key structural/functional component of many proteins and is present at high concentrations in the brain and retina, where it modulates ligand-gated receptors. Therefore, a study was made of the effects of zinc on homomeric neuronal nicotinic receptors expressed in Xenopus oocytes after injection of cDNAs encoding the chicken wild or mutant alpha7 subunits. In oocytes expressing wild-type receptors, Zn2+ alone did not elicit appreciable membrane currents.

Effects of fluoxetine on wild and mutant neuronal alpha 7 nicotinic receptors.

Fluoxetine is used in the treatment of a variety of clinical disorders including depression and obesity, and of cocaine detoxification or alcoholism. It is generally believed that fluoxetine exerts its clinical effects because it selectively blocks 5-hydroxytryptamine (5HT) reuptake into nerve terminals. In here we describe that fluoxetine antagonized the neuronal homomeric alpha 7 nicotinic acetylcholine receptors (nAChR) expressed in Xenopus oocytes, with an IC50 of 43 microM, when fluoxetine was coapplied with ACh, and of 1.

Formulation and characterization of calcium alginate beads containing ampicillin.

The purpose of this work was the preparation and characterization of calcium alginate beads containing ampicillin. Aqueous solutions of drug and sodium alginate (three viscosity grades) were added drop by drop to aqueous solutions of calcium chloride; the droplets instantaneously formed gel beads, which were then dried. Morphological studies and drug contents, in vitro release, and erosion tests were carried out for the characterization of the prepared beads.

Evaluation of preservative effectiveness in pharmaceutical products: the use of a wild strain of Pseudomonas cepacia.

A sodium benzoate-sorbic acid preservative system of a pharmaceutical product was proved effective against a wild strain of Pseudomonas cepacia, following the official method of the Italian and British Pharmacopoeias. However, this preservative system was ineffective against a challenge of Ps. cepacia wild strain cells grown in the unpreserved pharmaceutical product and on culture media different from those described by the Pharmacopoeias.

Neuronal nicotinic threonine-for-leucine 247 alpha7 mutant receptors show different gating kinetics when activated by acetylcholine or by the noncompetitive agonist 5-hydroxytryptamine.

Mutation of the highly conserved leucine residue (Leu-247) converts 5-hydroxytryptamine (5HT) from an antagonist into an agonist of neuronal homomeric alpha7 nicotinic acetylcholine receptor expressed in Xenopus oocytes. We show here that acetylcholine (AcCho) activates two classes of single channels with conductances of 44 pS and 58 pS, similar to those activated by 5HT. However, the mean open time of AcCho-gated ion channels (11 ms) is briefer than that of 5HT-gated ion channels (18 ms).

A novel Mn++-dependent ribonuclease that functions in U16 SnoRNA processing in X. laevis.

The intron-encoded U16 small nucleolar RNA (snoRNA) is a component of a new family of molecules which originate by processing of pre-mRNA in which they are contained. The mechanism of U16 snoRNA biosynthesis involves an initial step of endonucleolytic cleavage of the pre-mRNA with the release of a pre-snoRNA molecule; the subsequent step consists of exonucleolytic trimming that produces mature U16 molecules. In order to identify the molecular components involved in this peculiar biosynthetic pathway, we have undertaken the characterization of the endonucleolytic activity by biochemical fractionation of Xenopus laevis oocyte nuclear extract.

Prevalence, phenomenology and comorbidity of body dysmorphic disorder (dysmorphophobia) in a clinical population.

Dysmorphophobia (body dysmorphic disorder), defined as a preoccupation with an imaginary or minimal defect in appearance, has been known for more than a century but has received relatively little empirical study. The authors investigated the demographics, phenomenology, course, associated psychopathology and family history in a series of 58 patients (34 men and 24 women) with the disorder. The patients were assessed with the Hopkins Symptom Checklist and two specially constructed instruments developed by the authors.

Modulation of the dissolution profiles from Geomatrix multi-layer matrix tablets containing drugs of different solubility.

A new multi-layer tablet design has recently been proposed for constant drug release: Geomatrix Technology (Jago Pharma, Muttenz, Switzerland). It consists in the application of a drug-free barrier layer on one or both bases of an active core (hydrophilic matrix). The partial coating modulates the core hydration process and reduces the surface area available for drug release.

Cellulose acetate trimellitate ethylcellulose blends for non-steroidal anti-inflammatory drug (NSAID) microspheres.

Ketoprofen (Ket), a non-steroidal anti-inflammatory drug, has been incorporated into polymeric micromatrices (microspheres) prepared by a spray drying process and made of cellulose acetate trimellitate (CAT)/ethylcellulose (EC) blends. Drug loaded microspheres were obtained by spray-drying organic solutions of the two polymers and the drug. Characterization of the microparticles (morphology, particle size distribution, drug content, yield of production, surface properties, solvent residues) was carried out and in-vitro release behaviour measured.

Community-acquired pneumonia: is there difference in etiology between hospitalized and out-patients?

Since March 1991 a prospective 1-year study of patients with community-acquired, radiologically verified, pneumonia (CAP) was performed at the Divisione Pneumologica, Ospedali Riuniti Bergamo, and at the Centro Pneumo-Allergologico, Bergamo, Italy. The study included 119 out-patients and 60 in-patients, with a median age of 37.4 and 49.

Cellulose Acetate Trimellitate Microspheres Containing NSAIDS.

Indomethacin and ketoprofen (non-steroidal anti-inflammatory drugs) were incapsulated with cellulose acetate trimellitate, enteric polymer, using a spray drying technique.Organic solutions of polymer and drug were prepared in different weight ratios and sprayed, achieving drug loaded microspheres.The obtained spray dried microparticles were characterized in terms of yield of production, shape, size, morphological characteristics and drug content.

Cellulose acetate butyrate and polycaprolactone for ketoprofen spray-dried microsphere preparation.

Ketoprofen-loaded microspheres made with a polymeric blend were prepared by a spray-drying technique. Organic solutions of two polymers, cellulose acetate butyrate (CAB) and poly(epsilon-caprolactone) (PCL), in different weight ratios, and of ketoprofen (Ket) were prepared and sprayed, in different experimental conditions, achieving drug-loaded microspheres. The obtained spray-dried microspheres were characterized in terms of yield of production, shape, size, surface properties and drug content, and their in vitro drug release behaviours were determined at different pH values.

Health survey of workers occupationally exposed to cobalt.

The results are presented for a health control program using 236 male workers exposed to a cobalt inhalation risk. The study group consisted of grinders, producers of diamond tools, workers in metallurgical and mechanical industries (where Widia tools are processed and sharpened), and finally formerly exposed workers. All subjects received a clinical examination, the European Community for Coal and Steel questionnaire on respiratory complaints, a chest X-ray, pulmonary function test, electrocardiogram and determination of urinary cobalt; in 91 subjects, the metacholine bronchial provocation test was performed.