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The Portable Press Analyzer (PPA; Puuman Oy, Finland), a commercially available instrumentation for rotary tablet presses, was tested for accuracy of determination of force and displacement. The calibration of the force transducers (strain gauges) was tested under a static condition. The calibration of the displacement transducers (plastic film potentiometer) was compared for static and dynamic recordings. Force measurement was found precise (deviation1.1%) after alterations in the calibration procedure. Displacement measurement was affected by punch tilting and the application of the transducers. If tilting of punches was not considered, the deviation of displacement measurement from the true value (using steel tablets as a reference) was found up to 110 microns. By modifying the original PPA system by supplementing additional displacement transducers in the adjacent turret positions of the punches and adding a custom electronic device (Tilting Compensation Device), the accuracy of distance measurement was improved to 18.1 microns (+/- 3.64). Furthermore, machine and tooling deformation were recorded and found different under static and dynamic conditions. Correction of punch displacement for elastic deformation therefore should preferably be made from dynamic recordings.

In the crystal structure of the title compound, C8H9NO2, the topology of the hydrogen-bond network can be characterized by the graph-set C(6). The geometry of the hydrogen bonds in this compound is compared with the analogous parameters of similar compounds viz. acetanilide, paracetamol (forms I and II) and phenacetin.

The crystal structure of the title compound, C10H13NO2, has been redetermined in order to obtain more precise structure parameters.

In the paper by Hansen, Perlovich & Bauer-Brandl [Acta Cryst. (2003), E59, o1357–o1358], the coordinates of the R enantiomer of the title compound, C13H18O2, were incorrectly given instead of those of the S enantiomer. The correct coordinates of the S enantiomer are given here.

Solvates of the calcium-channel blocking agent felodipine with three structurally related high-boiling point solvents, dimethylacetamide (DMAA), dimethylethyleneurea (DMEU) and tetramethylurea (TMU), are described. The solvates can be formed either by solution crystallisation or solvent-drop mechanical grinding. In all of the crystal structures, the solvent molecule accepts an N–H⋯O hydrogen bond from felodipine. Analysis of the conformational preferences of the felodipine molecule in the crystal structures shows that it adopts a higher-energy conformation in the solvate with TMU. Hot-stage microscopy shows that the solvates decompose below the boiling point of the solvent, then the solvent condenses and dissolves the desolvated felodipine. The decomposition temperature of the solvate is correlated with the van der Waals molecular volume for the solvent molecule within the crystal structure. Measurements of the aqueous dissolution rate show that the concentration of felodipine during the first hour is increased by 4–6 times for dissolution of the solvates compared to pure felodipine.

The crystal structure of (S)-(+)-ibuprofen, C13H18O2, has been redetermined. It crystallizes in the monoclinic space group P21 with two mol­ecules in the asymmetric unit, giving a cyclic hydrogen-bonded dimer. All the H atoms were located from difference maps and refined isotropically.

The title compound, C9H9NO3, was crystallized from methanol. The monoclinic structure features one mol­ecule in the asymmetric unit. The topology of the O—H⋯O and N—H⋯O hydrogen-bond network can be characterized by the graph-set assignments C(9) and R22(14).

Die derzeitige Diskussion um den Begriff “Minimale cerebrale Dysfunktion“ kennzeichnet sich durch die grundsatzliche Problematik, das das Erscheinungsbild haufig unterschiedlich beschrieben, bewertet und definiert wird. Auser dem inzwischen stark verbreiteten Terminus “Minimale cerebrale Dysfunktion“ gibt es eine Vielzahl anderer, mehr oder weniger umfassender Bezeichnungen, die entweder als Synonyme verwendet werden oder bestimmte Teilaspekte des Phanomens abdecken. Hierzu gehoren: Hyperaktivitat bzw. hyperaktives Syndrom, Hyperkinesie bzw. hyperkinetisches Syndrom, motorische Unruhe, Impulsivitatsstorung, Unreife des Zentralnervensystems, leichte fruhkindliche Hirnschadigung, minimale Zerebralparese, fruhkindlich exogenes Psychosyndrom, Hirnreifungsverzogerung, leichte Hirnfunktionsstorung, zerebrale Leistungsstorung, neurogene Lernstorung, hirnorganisch-psychisches Achsensyndrom usw. Die Vielfalt der Begriffe macht deutlich, wie uneinheitlich die Auffassungen uber das Storungsbild gegenwartig noch sind, und last erkennen, das dasselbe Phanomen von verschiedenen wissenschaftstheoretischen und fachdidaktischen Standpunkten aus unterschiedlich akzentuiert wird.

As tablets are the most common dosage form for drug delivery, many different rotarypresses are available on the market in order to produce tablets with a high throughput.Single punch presses are used for pharmaceutical development or to simulate thecompaction process using small material quantities. In this study, 5 different rotary pressesand 4 single punch presses were utilized using 3 different model formulations. Tabletmasses and tensile strengths were investigated as a function of compaction force andprocess time. The corresponding force-time profiles were analyzed as well. In general,significant differences between the presses were observed even if the deviations wererather small from a practical point of view. The lowest variations of tablet properties werefound using the plastically deforming formulation, while the elastic formulation was morechallenging. High throughput with comparable high tablet tensile strength can be achievedby the brittle formulation. By analyzing representative force-time diagrams it was foundthat dwell times varied considerably between the different machines.

Supersaturated lipid-based drug delivery systems have recently been investigated for oral administration for a variety of lipophilic drugs and have shown either equivalent or superior oral bioavailability compared to conventional non-supersaturated lipid-based drug delivery systems. The aim of the present work was to explore supersaturated versus non-supersaturated lipid-based systems at equivalent lipid doses, on in vivo bioavailability in rats and on in vitro permeation across a biomimetic PermeapadⓇ membrane to establish a potential in vivo - in vitro correlation. A secondary objective was to investigate the influence of lipid composition on in vitro and in vivo performance of lipid systems. Results obtained indicated that increasing the celecoxib load in the lipid-based formulations by thermally-induced supersaturation resulted in increased bioavailability for medium and long chain mono-/di-glycerides systems relative to their non-supersaturated (i.e. 85%) reference formulations, albeit only significant for the medium chain systems. Long chain systems displayed higher celecoxib bioavailability than equivalent medium chain systems, both at supersaturated and non-supersaturated drug loads. In vitro passive permeation of celecoxib was studied using both steady-state and dynamic conditions and correlated well with in vivo pharmacokinetic results with respect to compositional effects. In contrast, permeation studies indicated that flux and percentage permeated of supersaturated systems, either at steady-state or under dynamic conditions, decreased or were unchanged relative to non-supersaturated systems. This study has shown that by using two cell-free PermeapadⓇ permeation models coupled with rat-adapted gastro-intestinal conditions, bio-predictive in vitro tools can be developed to be reflective of in vivo scenarios. With further optimization, such models could be successfully used in pharmaceutical industry settings to rapidly screen various prototype formulations prior to animal studies.