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Notes: Direct current SQUIDs (superconducting quantum interference devices) have been successfully fabricated by using a Pb-doped BiSrCaCuO superconducting thin film made by mixed evaporation of a single source composed of related components with a resistance heater. The dc SQUID comprises a square washer with a small hole. These SQUIDs show perfectly periodic voltage-flux characteristics without magnetic shield, that is, typically, the flux noise and energy resolution at a frequency range from dc to 1 Hz and at 78 K being 1.7×10−3 Φ0/(square root of)Hz and 3.6×10−26 J/Hz, respectively. Meanwhile, we have found out that one of the SQUIDs still was able to operate on flux-locked mode without bias currents and showed voltage-flux second harmonic characteristics. This phenomenon is not well understood, but it may be related to I-V (current-voltage) characteristics of the dc SQUID.

Notes: Proton pump inhibitors taken twice daily before meals (proton pump inhibitor b.d. AC) effectively controls daytime gastric pH; however, nocturnal gastric acid breakthrough (NAB) occurs in more than 75% of patients. Adding an H2-blocker at bedtime decreases NAB in normal subjects. The efficacy of this regimen has not been evaluated in GERD patients. The aim of this study was to assess the effects of proton pump inhibitor b.d., both with and without bedtime H2-blocker on intragastric pH and the occurrence of NAB in GERD patients.〈section xml:id="abs1-2"〉〈title type="main"〉Methods:Prolonged ambulatory pH studies in GERD patients were reviewed. Group A: 60 patients (mean age 53 years, male 30) taking either omeprazole 20 mg or lansoprazole 30 mg b.d. Group B: 45 patients (mean age 49 years, male 23) on proton pump inhibitor b.d. (omeprazole 20 mg or lansoprazole 30 mg) plus an H2-blocker at bedtime (ranitidine 300 mg, famotidine 40 mg or nizatidine 300 mg). Eleven patients were evaluated during treatment with both regimens (group C). The percentage time of nocturnal and daytime intragastric pH 〉 4 and per cent of patients with gastric NAB were analysed. In the patients with NAB, its duration and associated oesophageal acid exposure also were analysed.〈section xml:id="abs1-3"〉〈title type="main"〉Results:Median percentage time intragastric pH 〉 4 overnight was 51% in group A, compared to 96% in group B (P 〈 0.0001). Median percentage daytime pH 〉 4 was 73% in group A and 79.8% in group B (P=0.14). Median percentage time intragastric pH 〉p 4 overnight increased from 54.6% without H2RA to 96.5% after adding bedtime H2RA (P=0.0013) in group C patients. NAB occurred in 82% patients in group A and 40% in group B (P 〈 0.0001). The mean duration of oesophageal acid exposure during NAB was significantly shorter in group B (18 ± 6 min) than in group A (42 ± 9 min, P=0.04).〈section xml:id="abs1-4"〉〈title type="main"〉Summary:Adding a bedtime H2-blocker to the treatment enhanced nocturnal gastric pH control and decreased NAB compared to the proton pump inhibitor b.d. regimen. A bedtime H2-blocker also decreased oesophageal acid exposure during NAB.〈section xml:id="abs1-5"〉〈title type="main"〉Conclusion:Adding a bedtime H2-blocker to a proton pump inhibitor b.d. regimen should be considered in patients who require continued nocturnal gastric acid control whilst taking proton pump inhibitor b.d.

Notes: Single daily doses of proton pump inhibitors, omeprazole and lansoprazole provide effective acid suppression and equal healing and symptom relief in patients with GERD. Despite this, controversy exists as to the efficacy of available proton pump inhibitors in the control of gastric acidity.〈section xml:id="abs1-2"〉〈title type="main"〉Aim:To assess the efficacy of omeprazole 20 mg vs. lansoprazole 30 mg and omeprazole 40 mg vs. lansoprazole 30 mg in intragastric pH control.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:Study I: 12 Helicobacter pylori-negative volunteers (mean age 33 years) were treated with omeprazole 20 mg and lansoprazole 30 mg in random order before breakfast for 7 days. Study II: 24 subjects (mean age 36 years) were similarly treated with omeprazole 40 mg and lansoprazole 30 mg for 7 days after a baseline pH study. One week washout was allowed between studies. Subjects had the same meal on each study day. On day seven, a 24-h intragastric pH study was performed. The percentage time for which gastric pH 〉 4 was analysed (Gastrosoft, Synectics Medical Inc.) and expressed as mean ± s.d.〈section xml:id="abs1-4"〉〈title type="main"〉Results:(1) Omeprazole 20 mg and lansoprazole 30 mg showed no significant difference in the percentage time for which gastric pH 〉 4 in the daytime and night-time periods. (2) The percentage time for which pH 〉 4 with omeprazole 40 mg was significantly greater than lansoprazole 30 mg in both daytime (61 ± 19% vs. 48 ± 14%, P 〈 0.001), and night-time periods (34 ± 21% vs. 26 ± 14%, P 〈 0.05). (3) A large inter-subject variation existed in both studies. (4) In 10 subjects who participated in both studies, omeprazole 40 mg showed a significantly higher percentage time for which pH 〉 4 in the daytime (69 ± 18% vs. 51 ± 15%, P=0.015) than omeprazole 20 mg.〈section xml:id="abs1-5"〉〈title type="main"〉Conclusion:These pH data support the therapeutic equivalency of FDA approved doses of omeprazole and lansoprazole.