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Biomedical subjects

H Petersen

Publications and source records attributed to H Petersen.

At least 109 records · Page 6Linked to original sources
PubMed1988

Cimetidine responders in non-ulcer dyspepsia.

The effect of cimetidine and placebo was examined in 123 patients with non-ulcer dyspepsia (NUD) by means of a 12-day multi-crossover model with 5 regular interchanges between cimetidine and placebo. The evaluation of effect in individual patients was based on the number of times cimetidine was associated with less symptoms than the preceding or following placebo period. If cimetidine had no effect, the probability of being defined as a cimetidine responder was 25%. In general, cimetidine was associated with less symptoms than placebo (p less than 0.0001). Forty patients were identified as cimetidine responders (R) and the remaining patients were termed non-responders (NR). Symptoms compatible with gastroesophageal reflux were significantly more frequent in R than in NR, whereas the opposite was true for symptoms of the irritable colon syndrome. The ability of symptoms selected by stepwise logistic regression to predict response to cimetidine showed at best a sensitivity of 75% and a specificity of about 65%. No differences were found between R and NR with regard to acid secretion, endoscopic and histologic findings, or the result of an acid perfusion test. The present study supports the existence of a subgroup of cimetidine responders among patients with NUD characterized by symptoms suggestive of gastroesophageal reflux disease in the absence of confirmatory objective evidence.

Adult↗
PubMed1988

Over the counter sales of histamine-2 receptor antagonists.

Self treatment with H2 antagonists may have a positive impact on quality of life and costs. It may, however, also lead to incomplete peptic ulcer healing with frequent relapse and complications, inadequate long term treatment, neglectance of the life style type treatment for gastroesophageal reflux disease and a delay in the diagnosis of gastric malignancy. More research needs to be focused on the consequences of a more unrestricted and symptom guided use of H2 antagonists.

Dyspepsia↗
PubMed1988

Do we need to listen to the patient? The predictive value of symptoms.

We have previously shown that the endoscopist is able to predict the endoscopic diagnosis in about two thirds of the patients. We report some preliminary findings from two different studies on the ability of symptoms to predict endoscopic findings. Comparison with similar studies in Glasgow and Huddinge suggests that the predictive value of symptoms probably varies between countries and depends on the population dealt with as well as on the methods used for symptom evaluation. Predictive models for peptic ulcer or endoscopic esophagitis based on symptoms showed at best an about 60-70% sensitivity and specificity. We strongly feel that future studies on the predictive value of symptoms should be more focused on the first step in the decision process in general practice.

Esophagitis, Peptic↗
PubMed1988

Experience with a multi crossover model in dyspepsia.

A multi cross over model (MCOM) has been designed for single case studies. The model which is only partly randomized, implies regular interchanges between treatment periods with active drug and placebo. The individual evaluation is based on the number of times the active drug is associated with less symptoms than the preceding or following placebo period (X-score), while the effect in a group is evaluated according to the X-score distribution and a paired t-test. The advantages of the single case approach and the impact of the MCOM is illustrated by the results from a study of the effect of cimetidine in non ulcer dyspepsia. Although there are several statistical objections to the model, the results from the study are reasonable and demonstrate a small degree of violence of preassumptions.

Cimetidine↗
PubMed1987

Thymidine kinase, thymidylate synthase, and endothelial cell growth under hyperoxia.

To determine the respective role of thymidine kinase and thymidylate synthase activities in the hyperoxia-induced decrease in DNA synthesis and their relationship with cell replication, we measured these two enzyme activities in primary cultures of porcine aortic endothelial cells under different O2 concentrations for various durations. In confluent cells, exposure to 95% O2 for 5 days reduced thymidine kinase activity to 15% of control values; thymidylate synthase activity was unaffected. In preconfluent cells exposed to 95% O2 for 2 days, similar results were obtained, together with evidence for arrest in cell proliferation. Thymidylate synthase activity could therefore not be related to decreased cell proliferation under hyperoxia. [3H]thymidine incorporation into DNA, thymidine kinase activity, and cell proliferation were all similarly affected under exposure to graded O2 concentration for 2 days. Thymidine kinase appears to be a key enzyme in the modulation of DNA synthesis from thymidine and in its replication in endothelial cells.

Animals↗
PubMed1987

Pepsin secretion by the totally isolated, vascularly perfused rat stomach.

The gastric pepsin output by the totally isolated, vagally denervated, and both luminally and vascularly perfused rat stomach was studied. Basal release of pepsin was 3% of total gastric mucosal stores per hour. Topical (luminal) administration of 0.001 M HCl was without effect. Graded concentrations of pentagastrin, gastrin, histamine, and impromidine in the vascular perfusate were tested. Pentagastrin induced only a slight increase in pepsin release (15% of total content per hour). Gastrin had a more pronounced effect and elicited a significant increase in the pepsin output, reaching a maximum of 28% of total pepsin content per hour. The CD50 of gastrin was 0.061 nM. Histamine and impromidine likewise produced significant increases in the pepsin secretion (maximum, 40% and 35% of total stores per hour, respectively). When the CD50 of histamine (0.718 microM) was compared with that of impromidine (0.011 microM), impromidine on molar basis had 65 times higher potency than histamine as a pepsin secretagogue. When the pepsin and acid responses during gastrin, histamine, and impromidine stimulation were compared, the pepsinogen secretion was shifted to the left and thus was more sensitive to stimulation than the acid secretion.

Animals↗
PubMed1987

Dyspepsia: Therapeutic response as a diagnostic tool.

Non-ulcer dyspepsia (NUD) is a poorly defined heterogenous condition less well suited for the conventional randomized and placebo controlled parallel type trials. We have designed a multi cross-over model (MCO-model) with the facility of providing information about drug responses in individual patients. A pilot study suggested that the model may identify individual cimetidine responders among patients with dyspepsia. Preliminary findings from an ongoing study in patients with NUD supports the existence of a subgroup of cimetidine responders characterized by gastroesophageal reflux symptoms and possibly an increased basal acid secretion.

Cimetidine↗
PubMed1986

Sequelae of induced first-trimester abortion. A prospective study assessing the role of postabortal pelvic inflammatory disease and prophylactic antibiotics.

A follow-up study was undertaken in 493 women who had participated in a clinical, controlled trial with the object of assessing the role of postabortal pelvic inflammatory disease and prophylactic antibiotics in the development of sequelae. Information about dysmenorrhea, dyspareunia, chronic pelvic pain, episodes of pelvic inflammatory disease, infertility, births, induced and spontaneous abortions, and ectopic pregnancies were obtained from 382 of the women and from 38 of 40 women who had contracted postabortal pelvic inflammatory disease during the previous study. Significantly elevated rates in women with postabortal pelvic inflammatory disease compared with women without this disease were found for spontaneous abortion (22% versus 5%, p less than 0.0005), secondary infertility (10% versus 2%, p less than 0.05), dyspareunia (20% versus 5%, p less than 0.005), and chronic pelvic pain (14% versus 2%, p less than 0.001). Nonsignificant differences were observed for ectopic pregnancy and dysmenorrhea. A new episode of pelvic inflammatory disease within the first year after abortion was observed more often in women with postabortal pelvic inflammatory disease than in women without infection (41% versus 5%, p less than 0.0001). Prophylactic antibiotics decreased the rates of spontaneous abortion and dyspareunia (p less than 0.05 in both instances).

Abortion, Induced↗
PubMed1986

The trophic effect on the pancreas of long-term continuous intravenous infusion of secretin and a cholecystokinin-like peptide in rats.

Rats were treated for 5 days with continuous intravenous infusion of different doses of secretin and Thr28Nle31CCK25-33 (CCK-LP) alone and combined. The trophic effect on the pancreas was evaluated by means of pancreatic weight and contents of DNA, RNA, and protein. The acute effects on pancreatic protein secretion were studied in anesthetized rats. The findings generally confirmed the trophic effects of secretin and CCK-like peptides on the pancreas. No convincing evidence of potentiation was found between small doses of secretin and CCK-LP for either pancreatic growth or protein secretion. The maximal dose of CCK-LP was the same for pancreatic growth and for protein secretion (2.5 micrograms/kg-h). Potentiation was demonstrated between secretin and the maximal dose of CCK-LP for protein secretion. The maximal effect of CCK-LP on pancreatic growth, however, was not enhanced by secretin.

Animals↗
PubMed1986

1- and 4-week cimetidine treatment for duodenal ulcer.

Forty-eight patients with symptomatic duodenal ulcer were randomized to 4 weeks' treatment with cimetidine, 1 g/day (C4), or 1 week of cimetidine treatment followed by 3 weeks of placebo (C1 + P). The study was performed double blind. The symptoms were recorded daily on a visual analogue scale. Endoscopy was performed after 4 weeks. Two patients receiving C1 + P dropped out during the 2nd week because of worsening symptoms. With the two dropouts being recorded as 'unhealed ulcers', the 4-week healing rates were 16 of 24 (67%) and 15 of 24 (63%), with C4 and C1 + P, respectively (p greater than 0.05). Even without including the two dropouts, the patients treated with C1 + P had significantly more symptoms during the 2nd and 3rd treatment week than those treated with C4. The present study indicates that 1 week of cimetidine treatment is not sufficient in patients with duodenal ulcer.

Cimetidine↗
PubMed1986

Reproducibility of gastroesophageal reflux scintigraphy and the standard acid reflux test.

Patients with symptoms compatible with gastroesophageal reflux (GER) disease and asymptomatic controls were evaluated three times for GER by gastroesophageal reflux scintigraphy (GES) at intervals ranging from 6 h to 15 days and after various periods of fasting. Similarly, in patients and controls, pH monitoring at the distal esophagus was conducted three times by applying the standard acid reflux test (SART) at intervals ranging from 4 h to 3 days after different fasting periods. In 18 of 19 patients and 14 of 15 controls the results of SART were identical on all three occasions. A similar agreement was found for GES in 23 of 25 patients and 20 of 21 controls. The reproducibility of the induced type of reflux after ingestion of acidified orange juice was significantly better than that of the spontaneous types or the induced type of reflux after ingestion of saline. It is concluded that the reproducibility of GES and SART is similarly good.

Adult↗
PubMed1986

The clinical benefit of routine upper gastrointestinal endoscopy.

In a prospective study including 1526 consecutive endoscopies, attempts were made to characterize the benefit of upper gastrointestinal endoscopy. Before endoscopy judgements were made about the most likely diagnosis and treatment and about the degree of suspicion of upper gastrointestinal malignancy. After endoscopy the same types of judgement were made again. The study showed that about half of the endoscopies disclosed clinically significant abnormalities. Furthermore, about every third endoscopy led to unpredicted diagnostic and diagnostic and therapeutic consequences. The benefit was comparably small in patients below the age of 40 years and particularly great in patients above the age of 65, in patients submitted to endoscopy because of barium meal pathology or general suspicion of malignancy, and in patients with upper gastrointestinal bleeding. In general, the present study supports the widespread use of upper gastrointestinal endoscopy in clinical practice.

Adolescent↗