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Notes: A sequence of prograde isograds is recognized within the Dalradian Inzie Head gneisses where pelitic compositions have undergone variable degrees of partial melting via incongruent melting reactions consuming biotite. Three leucosome types are identified. At the lowest grades, granitic leucosomes containing porphyroblasts of cordierite (CRD-melt) are abundant. At intermediate grades, CRD-melt mingles with garnetiferous leucosomes (GT-melt). At the highest grades, CRD-melt coexists with orthopyroxene-bearing leucosomes (OPX-melt), while garnet is conspicuously absent. The prograde metamorphic field gradient is constrained to pressures of 2–3 kbar below the CRD-melt isograd, and no greater than 4.5 kbar at the highest grade around Inzie Head.A petrogenetic grid, calculated using thermocalc, is presented for the K2O–FeO–MgO–Al2O3–SiO2–H2O (KFMASH) system for the phases orthopyroxene, garnet, cordierite, biotite, sillimanite, H2O and melt with quartz and K-feldspar in excess. For the implied field gradient, the reaction sequence predicted by the grid is consistent with the successive prograde development of each leucosome type. Compatibility diagrams suggest that, as anatexis proceeded, bulk compositions may have been displaced towards higher MgO content by the removal of (relatively) ferroan granitic leucosome. An isobaric (P = 4 kbar) T–aH2O diagram shows that premigmatization fluids must have been water-rich (aH2O 〉 0.85) and suggests that, following the formation of small volumes of CRD-melt, the system became fluid-absent and melting reactions buffered aH2O to lower values as temperatures rose. GT- and OPX-melt formed by fluid-absent melting reactions, but a maximum of 7–11% CRD-melt fraction can be generated under fluid-absent conditions, much less than the large volumes observed in the field. There is strong evidence that the CRD-melt leucosomes could not have been derived by buoyantly aided upwards migration from levels beneath the migmatites. Their formation therefore required a significant influx of H2O-rich fluid, but in a quantity insufficient to have exhausted the buffering capacity of the solid assemblage plus melt. Fluid : rock ratios cannot have exceeded 1 : 30. The fluid was channelled through a regionally extensive shear zone network following melt-induced failure. Such an influx of fluid at such depths has obvious consequences for localized crustal magma production and possibly for cordierite-bearing granitoids in general.

Notes: Background: The optimum regimen for the eradication of Helicobacter pylori remains unclear. The aim of this study was to determine the efficacy and tolerability of omeprazole 40 mg daily given for 2 weeks, plus amoxycillin 500 mg t.d.s. and metronidazole 400 mg t.d.s. given for the first 7 days, in the treatment of H. pylori associated peptic ulcer disease. Results: One hundred and thirty-two consecutive patients with peptic ulcer disease were entered into the study (89 male, 41 female; median age 47 years; inter-quartile range: 36–58 years). H. pylori was eradicated successfully in 109 of 130 patients (intention-to-treat: 83%; 95% confidence limits: 76–89%); per protocol: 85% (95% CI: 78–91%)). Ninety per cent of patients completed the full course of therapy. Only four patients (3%) stopped treatment as a result of side effects although these occurred in 41% of patients. One patient developed pseudomembranous colitis requiring hospital admission. Conclusion: Omeprazole combined with one week of treatment of amoxycillin and metronidazole is an effective and well tolerated Helicobacter eradication regimen. Occasional severe side effects remain a risk, even when the duration of antibiotic exposure is reduced.

Notes: A 38-year-old man with seropositive arthropathy on long-standing treatment with diclofenac slow release presented with abdominal pain, diarrhoea and anaemia. Upper gastrointestinal endoscopy and barium series were unremarkable. Five months later he presented with a right iliac fossa mass. Investigations revealed discrete ulceration in the terminal ileum and caecum confirmed at laparotomy. Other possible causes of intestinal ulceration were excluded suggesting a diagnosis of non-steroidal anti-inflammatory drug associated intestinal ulceration.

Notes: Background: Giving antibiotics after meals prolongs their gastric residence time and improves their intragastric distribution. We aimed to see whether this would result in improved eradication of Helicobacter pylori.Methods: Eighty patients with H. pylori infection were treated with 40 mg omeprazole in the morning for 28 days and amoxycillin 500 mg q.d.s. for days 15–28. Amoxycillin dosing was randomised to either 1 h before or 10 min after food. Good compliance was pre-defined as missing less than four doses of amoxycillin or two of omeprazole.Results: Amoxycillin dosing after meals was shown not to affect H. pylori eradication rate either when results were analysed on an intention-to-treat basis [amoxycillin before meals successful in 63% (25/40), after in 65% 26/40)] or for good compliers only [before meals 81% (17/21), after 71% (20/28)]. This excludes, with 95% confidence, a benefit of greater than 18% from dosing before, or 23% from dosing after meals. Good compliance, however, was shown to be important, with H. pylori eradication in 76% (37/49) of good compliers compared with 48%(11/23) of others completing the protocol (P 〈 0.05).Conclusions: The timing of antibiotic administration in relation to meals is not important in the treatment of H. pylori infection with this regimen of amoxycillin capsules and omeprazole. Good compliance, is however, an important determinant of treatment success.

Notes: The aim of this study was to investigate the protective action of a new compound, ranitidine bismuth citrate, in the prevention of aspirin-induced acute mucosal injury to the upper gastrointestinal tract of healthy human volunteers. In a double-blind randomized three-way cross-over study 24 male volunteers received placebo, 900 mg aspirin or 900 mg aspirin and 800 mg ranitidine bismuth citrate at 12-h intervals for nine doses with a 2-week wash-out period between each treatment. The median (interquartile range) number of erosions seen at endoscopy when ranitidine bismuth citrate was given with aspirin (1 [0–4]) was significantly lower than aspirin alone (24 [16–32]) (P 〈 0.001) and not significantly different from either baseline or placebo (0 [0–2]). These findings were similarly reflected in the effects on microbleeding following the ninth dose: 12.1 (7.1–21.0) μL/10 min following aspirin alone compared to levels with placebo of 1.2 (0.4–2.9), and with aspirin and ranitidine bismuth citrate of 1.6 (0.8–2.6) (P 〈 0.005). Ranitidine bismuth citrate conferred substantial protection from aspirin-induced injury to the gastric and duodenal mucosa as determined by both endoscopic assessment and microbleeding rates, reducing injury to placebo levels.