Graham Buckton

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Seventy one patients with benign oesophageal strictures were randomised to receive balloon or bougie dilatation. Sixty five patients were eligible for analysis. At the end of five months the balloon group had significantly more dysphagia and the calibre of the strictures in the balloon group had narrowed by a greater degree. The methods were equally safe(More)
The need to be able to measure amorphous contents in crystalline powders is now recognised. In this review, calorimetric and gravimetric methods are reviewed in a way that should alert workers in the field to the theoretical, and practical considerations which are important to understanding how best to study crystalline samples which contain low levels of(More)
There is a realisation that small quantities of amorphous material can have a significant impact on the properties of crystalline solids. Consequently there is a growing interest in quantifying the amount of amorphous material that is present in "crystalline powders". Success has been reported when using isothermal microcalorimetry and vapour sorption(More)
Fifty patients with medically refractory gastro-oesophageal reflux were treated by the insertion of an Angelchik anti-reflux prosthesis. All patients had a pre-operative upper gastrointestinal endoscopy, 32 were investigated with 15 h overnight oesophageal pH studies combined with oesophageal bile sampling and 20 underwent oesophageal manometric studies. At(More)
Lactose solutions (20 g/100 mL) in distilled water were prepared and equilibrated at 25, 30, 40, and 50°C, then spray-dried using a Buchi 190 spray drier. The spraydrying variables were kept constant and were as described by Chidavaenzi et al, except for the feed rate, which was varied for each feed temperature to minimize fluctuations in the outlet(More)
The change in surface energy of cefditoren pivoxil powder as a consequence of changes in crystallinity (caused by milling duration) was studied using inverse gas chromatography (IGC) under dry conditions. The surface of the powder became more basic with decreasing crystallinity. It was suggested by considering the results of IR spectra that this resulted(More)
The effect of spray drying lactose alone and in the presence of polyethylene glycol 4000 was investigated. Lactose was added to distilled water to give concentrations of 10, 20, 30 and 40g/100ml at room temperature and each spray dried in turn. Identical samples were prepared to which polyethylene glycol (PEG) 4000 was added (12% by weight of lactose) prior(More)
The objective of this study was to investigate the reasons for the difference in physical stability of two amorphous cefditoren pivoxil samples that had been prepared using spray drying at inlet-air temperatures of 40 degrees C (SD-A) and 100 degrees C (SD-B). The two samples appeared amorphous by powder X-ray diffraction and had indistinguishable glass(More)
Some studies have shown that the mixing order of drug, fines and coarse carrier in a ternary dry powder inhaler (DPI) formulation affects fine particle delivery; others have seen no difference. This was investigated by examining the influence of salbutamol sulphate concentration (0.5-4.5%(w)/(w)), mixing time and blending order (drug and lactose carrier(More)
The purpose of this work was to characterize theophylline (THF) cocrystals prepared by spray drying in terms of the physicochemical properties and inhalation performance when aerosolized from a dry powder inhaler. Cocrystals of theophylline with urea (THF-URE), saccharin (THF-SAC) and nicotinamide (THF-NIC) were prepared by spray drying. Milled THF and(More)