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Abstract: In this paper the role of V5+ and V3+ ions in V/P/O, catalyst for the oxidation of n-pentane to maleic and phthalic anhydrides, has been investigated. These species have transient lifetime, since the stable, fully equilibrated catalyst only contains vanadyl pyrophosphate, (VO)2P2O7, and V4+ ions. Therefore, first the formation of V5+ and V3+ species has been induced in catalysts, either by means of a suitable oxidative treatment on a equilibrated V/P/O catalyst, to generate controlled amounts of V5+, or by adopting a preparation procedure which leads to the formation of discrete amounts of V3+ in fresh catalysts. Thereafter, the evolution of catalytic performance was followed along with time-on-stream. A relationship was found between the distribution of products, and the oxidation state of V in catalysts. Higher concentrations of V5+ led to the preferred formation of maleic anhydride, while samples having average V valence state close to 4.00+ and well-crystallized vanadyl pyrophosphate were the most selective to phthalic anhydride. The latter samples were also characterized by the higher Lewis-type acid strength. The reduced catalyst, containing a large amount of V3+ ions, was instead non selective towards either of phthalic and maleic anhydrides; the progressive catalyst oxidation in the reaction environment led to the increase in the yield to both products. [Copyright &y& Elsevier]

A letter to the editor is presented about a research on the effect of procalcitonin on antibiotic usage of patients with respiratory infections.

The article evaluates a pre-conceptual screening program using serological testing for chickenpox in Great Britain. The varicella vaccine utilized in the screening program is safe in non-pregnant women and is effective in preventing chickenpox. The benefits of the program included prevention of maternal, fetal and perinatal chickenpox and avoidance of all the associated morbidity and mortality. There was also avoidance of the cost for diagnosis and treatment of the fetal/perinatal chickenpox.

Abstract: A solubility phase study was carried out to investigate the ability of Poloxamer 407 (P407) to solubilise tolfenamic acid. P407 considerably enhanced the solubility of this anti-inflammatory agent, by increasing its concentration in aqueous solution at least 2000-fold (up to C =4mM), when present at 12% (w/w) at 25°C. The solubilisation process was spontaneous and exothermic, as indicated by thermodynamic parameters. A mixture experimental design was used to investigate the physical and release properties of P407-based gel formulations. The experimental design allowed verifying that drug release, occurring through a Fickian diffusion mechanism, was independent of the bulk viscosity of the system. The sustained release of tolfenamic acid towards the receptor phase constituted by isopropyl myristate was accompanied, in its early stage, by the concomitant release of ethanol and tetrahydrofurfuryl alcohol (THFA) used as cosolvents to obtain a drug loading of 0.6% (w/w). The poloxamer micellar phase was directly involved in the late stage of drug release, thus indicating that a strong interaction occurred in the gel between the poloxamer and tolfenamic acid. Results point out the possibility of both the systemic and topical administration of tolfenamic acid by means of aqueous solutions or gels containing P407 at an adequate concentration. [Copyright &y& Elsevier]

Abstract: In this work, nanoparticles with a negative or positive surface charge were prepared through electrostatic interaction of an anionic cisplatin–alginate complex with a cationic polyelectrolyte, namely chitosan or N-trimethyl chitosan (substitution degree of 85%). Statistical experimental design allowed the study of the influence of component amounts on the characteristics of nanoparticles. Mean particle diameter ranged from 180 nm to 350 nm. After 24 h, while the cisplatin–alginate complex released almost all the drug in saline-buffered solution at pH 7.4, approximately 40% w/w of total cisplatin was released from negative nanoparticles and roughly 50% w/w from positive ones. The same cumulative amounts of released drug were found after 48 h, with a progressive reduction to lower values up to 6 days. Drug loading of nanoparticles with a positive zeta potential (43 mV–60 mV) ranged from 13% w/w to 21% w/w and particle yield, referred to total polymers, was about 15% w/w (50% w/w if referred to cisplatin–alginate complex). Nanoparticles with a negative zeta potential (−34 mV) were obtained with a yield of 40% w/w and a drug loading of 18% w/w. These nanoparticles were the least active on all cell lines tested, while the cytotoxic activity of the positive nanoparticles was similar to or lower than that of cisplatin, probably depending on the combination of sizes and zeta potential values, on P388 murine and A2780 human cells. On A549 human cells, the nanoparticles with the smallest size and the lowest positive zeta potential were more active than cisplatin and showed a similar capability in inducing apoptosis in A2780 human cells. These results indicate that cisplatin complexes with polycarboxylate polymers can be transformed into cisplatin particulate carriers of high potential interest. [Copyright &y& Elsevier]

Abstract: The aim of this work was to prepare and evaluate a matrix for buccal drug delivery composed of a chitosan salt and poloxamer 407. Different chitosan salts were formed by reacting chitosan with acetic, citric, and lactic acid. Various proportions of poloxamer 407 were added to the aqueous solution of chitosan salt, and the residue obtained by lyophilisation was compressed into discs, using a 30 kN compression force. An experimental design (32) was used to study the influence of the type of chitosan salt and of the relative amount of poloxamer on drug release capacity, swelling, erosion, and mucoadhesiveness of matrices. The results showed that matrix properties depended significantly on both relative amount of poloxamer and chitosan salt type. The rank orders of chitosan salts for the four processes evaluated were as follows: drug release: chitosan acetate>chitosan citrate>chitosan lactate; swelling: chitosan lactate>chitosan acetate=chitosan citrate; erosion: chitosan citrate>chitosan lactate>chitosan acetate; mucoadhesion: chitosan lactate>chitosan acetate=chitosan citrate. Mucoadhesion was particularly favoured when poloxamer 407 was present at about 30% (w/w). The matrix composed of chitosan lactate and poloxamer 407 showed the best characteristics for buccal administration. [Copyright &y& Elsevier]

The aim of this tutorial is to show the application of a mixture experimental design to a problem of pharmaceutical formulation. A gel, based on poloxamer 407, useful for topical administration of tolfenamic acid, a potent anti-inflammatory drug very poorly soluble in water, has been prepared, and a mixture experimental design was used to study the influence of the components on the viscosity of the formulation. Its application allowed to identify a critical boundary, separating semisolid formulations from liquid ones, within a narrow interval of concentrations of the components, and to estimate their effects on the viscosity of the preparation. [Copyright &y& Elsevier]

Abstract A survey was carried out by personal interview to assess the awareness of basic food hygiene and food safety amongst 77 HIV-positive individuals attending a single hospital. There was some confusion and lack of knowledge about aspects of food storage and despite the fact that 74% of subjects had modified their diet since learning their HIV status (mainly for nutritional reasons) only 25% reported receiving information on food safety. Of the subjects interviewed, 96%, 66% and 23% were aware of the risks of infection from Salmonella, Listeria monocytogenes and Cryptosporidium, respectively; although most were not aware of the UK Government's advice on the consumption of eggs, soft cheese, pate and cook-chill foods. Over 40% of those interviewed reported that they did not drink tap water (most drank bottled water instead), but few were aware of infections potentially transmitted through water. Although pets represent a potential source of a wide variety of infectious agents, there was a high level of awareness of this problem. This study highlights the need for improving the availability of information on food hygiene and infections acquired through food and water to HIV-positive individuals. [ABSTRACT FROM AUTHOR]

A survey was carried out by personal interview to assess the awareness of basic food hygiene and food safety amongst 77 HIV-positive individuals attending a single hospital. There was some confusion and lack of knowledge about aspects of food storage and despite the fact that 74% of subjects had modified their diet since learning their HIV status (mainly for nutritional reasons) only 25% reported receiving information on food safety. Of the subjects interviewed 96%, 66% and 23% were aware of the risks of infection from Salmonella, Listeria monocytogenes and Cryptosporidium, respectively; although most were not aware of the UK Government's advice on the consumption of eggs, soft cheese, pat'e and cook-chill foods. Over 40% of those interviewed reported that they did not drink tap water (most drank bottled water instead), but few were aware of infections potentially transmitted through water. Although pets represent a potential source of a wide variety of infectious agents, there was a high level of awareness of this problem. This study highlights the need for improving the availability of information on food hygiene and infections acquired through food and water to HIV-positive individuals. [ABSTRACT FROM AUTHOR]