Diagnostic tests for Helicobacter pylori--can they help select patients for endoscopy?

AIM: Dyspepsia is a common symptom and some selection process for endoscopy is required. This study seeks to determine if noninvasive tests for Helicobacter pylori could be useful as a screening test to help select patients for endoscopy. METHODS: Consecutive patients attending for upper gastrointestinal endoscopy were interviewed prior to endoscopy and the endoscopic diagnoses was recorded. The presence of Helicobacter pylori infection was assessed by serology. Some patients also had a 13C urea breath test or rapid urease test (CLO test). RESULTS: 436 consecutive patients were evaluated. The endoscopy findings were normal in 44%, 29% had reflux oesophagitis, 18% had duodenal ulcer, duodenitis or gastric ulcer and 9% had other diagnoses. 54.8% of patients were positive for Helicobacter serology. Using either the CLO test or 13C urea breath test as the confirmatory test for the diagnosis of Helicobacter pylori, the sensitivity of the serology test was 96% and 91% respectively and the specificity was 66.6 and 82%. Patients with negative serology and no history of recent NSAID or aspirin use comprised 34% of the total with dyspepsia or reflux symptoms. There were no gastric or duodenal ulcers in this group. CONCLUSION: The serology test may have some potential or the initial evaluation of dyspepsia. These tests need to be prospectively evaluated in general practice.

Metabolic effects of recombinant human growth hormone: isotopic studies in the postabsorptive state and during total parenteral nutrition.

We have performed a series of isotopic studies in 25 adult patients with sepsis and/or trauma in order to determine the metabolic effects of recombinant human growth hormone (rHGH) administration. Twelve of the patients were receiving total parenteral nutrition, and 13 were eating a normal ward diet and were studied postabsorption. Energy and protein kinetics were quantified isotopically before rHGH administration and following a 3-day course of rHGH (20 units subcutaneously daily). In the total parenteral nutrition group the rate of net loss of protein decreased from 0.82(0.17) g kg-1 day-1 to 0.43(0.20) g kg-1 day-1 (P less than 0.02) following the administration of rHGH. The rate of appearance of leucine was not altered, suggesting that the improvement in nitrogen balance following rHGH was because of an increased rate of protein synthesis rather than reduced catabolism. In the postabsorptive group, rHGH treatment significantly increased the rate of appearance of free fatty acids (from 7.4(2.2) mumol kg-1 min-1 to 11.1(2.6) mumol kg-1 min-1, P less than 0.03) and free fatty oxidation (from 1.3(0.4) mumol kg-1 min-1 to 1.7(0.4) mumol kg-1 min-1, P less than 0.06), while the rate of leucine oxidation was reduced (from 0.44(0.05) mumol kg-1 min-1 to 0.26(0.03) mumol kg-1 min-1, P less than 0.005). Glucose appearance and oxidation remained unchanged. These results suggest that fat was being oxidized in preference to protein, which resulted in a reduction in the net rate of loss of protein of 0.3 g kg-1 day-1 (P less than 0.05). We conclude that rHGH administration is capable of significantly reducing net protein loss in septic or injured surgical patients. Recombinant HGH may be clinically useful in supporting critically ill surgical patients who require intensive nutritional support.

Glutamine synthetase in the chloroplasts of Vicia faba.

A glutamine synthetase has been localised in the chloroplasts of Vicia faba. The enzyme has requirements for Mg(2+) and ATP in the biosynthetic reaction and in addition will catalyse a γ-glutamyl transferase reaction in the presence of Mn(2+) and arsenate. The enzyme is inhibited by AMP, CTP, glycine and alanine. These results are discussed in relation to the possible chloroplastic synthesis of nucleotide bases. Estimations of glutamine amide-2-oxoglutarate amino transferase (oxido-reductase) have demonstrated only low levels of activity in the chloroplast extracts. This enzyme is generally active in organisms where GS has an assimilary role. It is coneluded that glutamine synthetase has a biosynthetic and not an assimilatory role in the chloroplast.