Regulation of transforming growth factor beta by sex steroids.
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Animals↗
Biomedical subjects
A Pfeiffer
Publications and source records attributed to A Pfeiffer.
Muscarinic receptors in gastric mucosa are increased in peptic ulcer disease.
Muscarinic receptors stimulate the secretion of acid pepsinogen and mucous in gastric mucosa. Whether muscarinic receptors are involved in the pathogenesis of benign gastric disease is unknown. Receptor changes in these conditions were therefore sought. An autoradiographic technique was developed to determine quantitatively muscarinic receptors in microtome sections of biopsy specimens obtained during gastroscopy. Muscarinic receptor density was mean (SEM) 18.4 (1.2) fmol/mg protein in the corpus and 8.9 (0.7) fmol/mg protein in the antrum (n = 53). Neither chronic nor active gastritis was associated with receptor changes in the antrum but chronic gastritis was associated with a receptor loss in the corpus. Patients with acute or recent duodenal or antral ulcers (n = 23) had significantly higher levels of muscarinic receptors in the corpus than controls (n = 25) (22.2 (1.5) v 16.9 (1.7) fmol/mg protein respectively (p < 0.025). These results suggest that muscarinic M3 receptor is overexpressed in duodenal ulcer disease and may play a part in its pathogenesis.
Acute Disease↗
A subgroup of LHRH neurons in guinea pigs with progestin receptors is centrally positioned within the total population of LHRH neurons.
Although the role of gonadal steroids in inducing the LH surge is undisputed, the mechanism(s) whereby steroids induce the release of the hypothalamic luteinizing hormone-releasing hormone (LHRH) remain(s) enigmatic. In this study we examined the issue of the presence of steroid receptors in LHRH neurons using a mammalian species that has a true luteal phase, namely, guinea pigs. Progestin receptors (PR) were localized in LHRH neurons of ovariectomized guinea pigs administered estradiol (10-20 micrograms estradiol benzoate) for 3-4 days, using several different immunocytochemical protocols. The subgroup of LHRH neurons containing PR, although small, was strategically positioned within the core of the total population of LHRH neurons. This central position was visualized in simultaneous views of three-dimensional computer reconstructions of the populations of LHRH/PR neurons and LHRH neurons. The subgroup of LHRH/PR neurons formed a thread permeating the population of LHRH neurons. We propose that in guinea pigs, LHRH neurons containing progestin receptors, are foci of activity, capable of activating a larger component of the LHRH population of cells in certain endocrine conditions, such as prior to the LH surge.
Animals↗
Abnormal oesophageal pH-monitoring in patients with functional thoracic and abdominal disorders.
BACKGROUND AND OBJECTIVES: Controversial data are reported on the diagnostic yield of oesophageal pH-monitoring in clinical routine. The aim of this study was to determine the diagnostic importance of oesophageal pH-monitoring in the work-up of functional thoraco-abdominal disorders. METHODS: The prevalence of abnormalities in pH-monitoring was evaluated in 238 patients with functional complaints: typical reflux symptoms (n = 56), non-cardiac chest pain (n = 98), non-ulcer dyspepsia (n = 52), and unclassifiable abdominal pain (n = 32). A symptom index was calculated for reflux-related symptoms in patients experiencing symptoms during the measurement (n = 74). RESULTS: The rate of patients with an abnormal pH-monitoring were in patients with reflux symptoms non-cardiac chest pain, non-ulcer dyspepsia and unclassified abdominal pain 55, 50, 44 and 34%, respectively. A symptom index of at least 50% was observed in 77, 55, 50 and 60% in the four groups respectively. CONCLUSION: The high rate of abnormal oesophageal pH-monitoring and symptom related reflux events in the investigated patients emphasizes the importance of 24-hour oesophageal pH-measurement in the diagnostic work-up of functional thoracic and abdominal disorders.
Abdominal Pain↗
[Participation in continuing education by German physicians--exemplified by the Schleswig-Holstein study].
In order to evaluate the CME behaviour of the physicians in the state of Schleswig-Holstein, the State Society of Physicians questioned all its members (n = 10,326 and 10,698) regarding the participation in CME activities during the previous year using the same questionnaire in 1991 and 1993. Answers were obtained from 6,329/6,904 physicians where 40.2/42.2% (1991/1993) worked in free practice, 46.9 (44.6)% in hospitals, 6.2 (6.9) % in administrative and scientific institutions, 5.2 (2.9)% in various medical occupations, and 1.6 (3.3)% without medical professions. CME activities were identical in 1990 and 1992, where the study of literature was the most relevant activity (99%). Mean reading time was 5.8/5.6 hours per week (physicians in practice: 5.3/5.3 hpw, in hospital 6.4/6.6 hpw), average of read journals: 3.9/3.9 (practice: 4.3/4.3 hospital: 3.6/3.6). Video-CME was documented with 41.7/44.2% in total (practice: 50.5/52.3%-hospital: 37.2/39.9%). Regarding CME courses and conferences, traditional class-room CME was used most frequently (total: 71.9/72.6%-practice: 69.7/71%-hospital: 73.9/74.9%), followed by workshops (total: 50.3/47.9%-practice: 56.4/54.1%-hospital: 45.6/54.1%) and training in small groups (total: 16.6%-practice: 20.9/19.2%-hospital: 13.2/12%). Physicians participated in CME courses and conferences usually in the evenings (7.6/7.2 times a year), followed by halfdays courses (1.4 times), weekend courses (1.4 times) and conferences lasting several day (1.2/1.3-practice: 0.8/0.9-hospital: 1.6/1.6). This study about CME activities firstly demonstrated both the representativity of systematic questionnaires based on the rules of the medical profession, as well as the continuity of the CME behaviour in Germany. The results proof that repeated questionnaires are of little influence on the answering behaviour of physicians.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
[Examination of feed and slurry additives for decrease of ammonia emissions in swine housing].
Ammonia emissions from animal farming have negative effects inside and outside of animal housings. Numerous feed or slurry additives are offered to reduce the ammonia emissions from pig keeping. Investigations were carried out to test the effectiveness of a clinoptilotite-containing feed additive named "Klinofeed" on practical farms and in laboratory experiments. Some effects of ammonium retention were seen in the laboratory tests, which also revealed informations on the absorption mechanisms of ammonium ions. The field experiments didn't show any ammonia reducing effect of the additive. It is recommended to develop a standardized procedure of testing the effectivity and usefulness of feed and slurry additives which are manufactured and sold for ammonia reduction purposes. The presented experiment could be a first basis for such a test procedure.
Air Pollution↗
Additional isoforms of multifunctional calcium/calmodulin-dependent protein kinase II in rat heart tissue.
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Amino Acid Sequence↗
Characterization of gamma- and delta-subunits of Ca2+/calmodulin-dependent protein kinase II in rat gastric mucosal cell populations.
We searched for the occurrence of a Ca2+/calmodulin-dependent protein kinase in rat gastric cell types as a likely member in the chain of gastrin- and muscarinic-receptor-mediated signal transmission. A Ca(2+)- and calmodulin-dependent phosphorylation of major 50, 60 and 100 kDa substrates was observed in parietal cell cytosol and a major 60 and 61 kDa protein doublet was found to bind 125I-calmodulin in 125I-calmodulin-gel overlays. A specific substrate of the multifunctional Ca2+/calmodulin-dependent protein kinase II, autocamtide II, was phosphorylated in a calmodulin-dependent manner. The specific inhibitor of this enzyme, KN-62, antagonized protein kinase activity. RNA extracted from gastric mucosal cells was shown to contain sequences of the gamma- and delta- but not alpha- and beta-subunits of the calmodulin-dependent kinase II, and mRNA of both subtypes was demonstrated in highly purified parietal, chief and mucous cells. A calmodulin-dependent kinase II composed of gamma- and delta-subunits is a likely mediator of Ca(2+)-dependent signal transmission in these populations of gastric cells.
1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
Okadaic acid indicates a major function for protein phosphatases in stimulus-response coupling of RINm5F rat insulinoma cells.
Stimulus-induced insulin secretion involves the activation of several protein kinases within the beta cell. Most prominent are protein kinase A, protein kinase C and calcium/calmodulin-dependent protein kinases. Protein kinase action is functionally antagonized by protein phosphatases. The four ubiquious serine/threonine protein phosphatases are termed PP-1, PP-2A, -2B and -2C. PP-1 and PP-2A are in vivo parts of major protein complexes. These complexes presumably regulate the phosphatase activity and direct the enzyme to its site of action. Therefore, PP-1 and -2A could play an important role in controlling intracellular signal transmission. Two different toxins, okadaic acid and calyculin A, both from marine invertebrates, were recently discovered and identified as potent and highly specific inhibitors of PP-1 and PP-2A. Both compounds emerged as very useful tools for studying intracellular phosphorylation events. We took advantage of these substances to investigate the significance of protein phosphatase action in stimulus-induced insulin secretion. To avoid major complexity, we confined our study to the cAMP and the phosphoinositide signal pathway. Okadaic acid alone evoked virtually no secretory response. cAMP-dependent secretion was markedly enhanced by 1 microM okadaic acid. The stimulatory effect of okadaic acid was strongly dependent on the concentration of cAMP analoga. In contrast, insulin release caused by the cholinergic agonist carbachol was not influenced by okadaic acid. Calyculin A (10 nM) slightly increased cAMP-induced secretion, but its high toxicity prohibited accurate interpretation of the data. Our findings support the idea that serine/threonine phosphatases act as important regulators in stimulus response coupling.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Effect of decaffeination of coffee or tea on gastro-oesophageal reflux.
BACKGROUND: Coffee and tea are believed to cause gastro-oesophageal reflux; however, the effects of these beverages and of their major component, caffeine, have not been quantified. The aim of this study was to evaluate gastro-oesophageal reflux induced by coffee and tea before and after a decaffeination process, and to compare it with water and water-containing caffeine. METHODS: Three-hour ambulatory pH-metry was performed on 16 healthy volunteers, who received 300 ml of (i) regular coffee, decaffeinated coffee or tap water (n = 16), (ii) normal tea, decaffeinated tea, tap water, or coffee adapted to normal tea in caffeine concentration (n = 6), and (iii) caffeine-free and caffeine-containing water (n = 8) together with a standardized breakfast. RESULTS: Regular coffee induced a significant (P < 0.05) gastro-oesophageal reflux compared with tap water and normal tea, which were not different from each other. Decaffeination of coffee significantly (P < 0.05) diminished gastro-oesophageal reflux, whereas decaffeination of tea or addition of caffeine to water had no effect. Coffee adapted to normal tea in caffeine concentration significantly (P < 0.05) increased gastro-oesophageal reflux. CONCLUSIONS: Coffee, in contrast to tea, increases gastro-oesophageal reflux, an effect that is less pronounced after decaffeination. Caffeine does not seem to be responsible for gastro-oesophageal reflux which must be attributed to other components of coffee.
Adult↗
Effect of the quaternary ammonium compound trospium chloride on 24 hour jejunal motility in healthy subjects.
This study aimed to record 24 hour jejunal motility in healthy ambulant subjects and to analyse changes in motility caused by the oral administration of an anticholinergic agent, the quaternary ammonium compound, trospium chloride. In a placebo-controlled, double blind crossover trial, 24 hour jejunal motility was recorded in 12 healthy volunteers, aged 25 (21-30) years, using a digital data logger connected to two strain-gauge transducers mounted 20 cm apart in a flexible nasojejunal catheter. A computer program was developed to determine contraction parameters. Trospium chloride (15 mg orally thrice daily) prolonged the duration of irregular contractile activity after meals (p < 0.02) and reduced its contraction frequency and amplitude (p < 0.001). In the fasting state, the cycle length of the migrating motor complex was prolonged (p < 0.01) by an extended phase I (p < 0.025). Phase III was shortened (p < 0.005) and showed a slower aboral migration velocity (p < 0.005). Clustered contractions were less frequent during postprandial and fasting periods (p < 0.01). Runs of clustered contractions were completely absent with trospium chloride. Digital manometry was useful for long term recordings of jejunal motility and enabled the motor effects of an anticholinergic agent to be characterised in ambulant subjects.
Adult↗
Effect of foot position on gastrocnemius/soleus stretching in subjects with normal flexibility.
Following injury to the ankle or lower extremity, stretching of the gastrocnemius/soleus complex is commonly prescribed. Many authors recommend stretching the gastrocnemius/soleus complex with the foot placed in a supinated position. No research is available, however, that supports the efficacy of stretching in the supinated vs. the pronated position. Therefore, the purpose of this study was to compare the effect of stretching the gastrocnemius/soleus complex in two foot positions: supinated and pronated. Eleven female and eight male subjects completed 10 stretching sessions with one foot supinated and the other foot pronated. Each stretching session consisted of four 20-second stretches. On pretest and posttest measurements, maximum dorsiflexion range of motion and stretching force exerted through the foot were recorded for each subject. Foot position for the testing procedures and the stretching phase was standardized with individually constructed footprint templates. A two-way analysis of variance (stretching position and time) was used to compare pretest and posttest ankle dorsiflexion measurements. Results indicated a significant increase in dorsiflexion (p = 0.01, pronation + 6.36%, supination + 6.24%) but no significant difference between stretching positions (p = 0.23). We concluded that gastrocnemius/soleus complex stretching in either foot position is effective for increasing dorsiflexion range of motion in healthy subjects with normal flexibility of the gastrocnemius/soleus complex.
Adult↗
Computerized analysis of ambulatory long-term small-bowel manometry.
BACKGROUND: Ambulatory long-term manometry is increasingly being used to study small-bowel motility. This study aimed to develop computer-aided data analysis including the elimination of artefacts, identification of individual phasic contractions, and analysis of aboral propagation. METHODS: Data processing included low-pass filtering, base-line adaptation, cross-comparison of channels, and application of threshold values for contraction parameters. Automated analysis was validated by a visual reference standard. RESULTS: Artefacts were related to cardiovascular and respiratory activity, changes in body posture, and contractions of the abdominal wall. Automated recognition of contractions reached a sensitivity of 92% and a positive predictive value of 88% compared with the visual standard. Mean contraction amplitude and duration of computer analysis were 96% and 93%, respectively, of the visually obtained values. Propagation analysis under ambulatory conditions showed good agreement with previous results by stationary recordings. CONCLUSIONS: Computerized analysis provided valid and reproducible data on small-bowel phasic contractile events and propagative activity by digital long-term manometry.
Adult↗
New isoforms of multifunctional calcium/calmodulin-dependent protein kinase II.
Calcium/calmodulin dependent protein kinase II (CaM kinase II) seems to act as an important regulator of intracellular signal transmission. Four subtypes, termed alpha to delta, have been cloned; some of them can exist as different splicing variants. All these isoforms share a great overall homology, and they contain 3 areas of low homology. We have identified 5 new variants of subtype delta so that the total number of different isoforms now adds up to 12. These variants are probably a result of different splicing and show several deletions in regard to subtype delta. The deletion sites do exactly match regions of low homology between the subtypes. This suggests a functional division of the CaM kinase II molecule into homologous and variable domains. The homologous domains are highly conserved. Therefore, it might be the case that the constitution of the variable domains is more significant for a certain isoform than its belonging to one of the 4 subtypes alpha to delta.
Alternative Splicing↗
[Diagnostic errors in symptoms of endocrinologic diseases].
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Adenoma↗
Effect of trospium chloride on gastrointestinal motility in humans.
The aim of this double-blind, placebo-controlled, cross-over study was to investigate the effect of trospium chloride on gall bladder contraction, gastric emptying of a liquid meal, gastrooesophageal reflux, and orocaecal transit time in healthy subjects. Gall bladder contraction was examined by ultrasonography before and after stimulation with two raw eggs. Gastric emptying was evaluated by an intubation technique and by sonography. To determine gastrooesophageal reflux and orocaecal transit time, 24-hour pH metry and a hydrogen breath test were used. The gall bladder ejection fractions were significantly lower after oral treatment with both 4 x 10 mg and 4 x 20 mg trospium compared to placebo, but no difference was seen between the two doses of drug. Gastric emptying of a liquid meal was significantly delayed after intake of 4 x 15 mg trospium, whilst the time course of the intragastric volume determined by ultrasound did not differ from that after placebo, suggesting an antisecretory effect of trospium on gastric secretion. The fractional time of oesophageal pH < 4 as a percentage of the entire 24-hour investigation period was significantly increased by treatment with trospium 3 x 15 mg per day. The orocaecal transit time of 10 g lactulose was significantly prolonged. Provided that the observed effects on gall bladder contraction, gastric emptying, and orocaecal transit time are reproduced in disease states, trospium should be regarded as a potentially useful antispasmodic agent.
Adult↗
Low-proof alcoholic beverages and gastroesophageal reflux.
Previous studies have demonstrated an increased gastroesophageal reflux after the ingestion of high-proof alcoholic beverages in normal subjects. Data on gastroesophageal reflux with usual amounts of low-proof alcoholic beverages are not available. The effect of white wine (7.5% v/v, pH 3.2) and beer (7.0% v/v, pH 4.5) was compared with water, a nonalcoholic beverage of pH 3.2, and an ethanol solution (7.5% v/v, pH 7.6) using ambulatory pH measurement in healthy volunteers. The fraction of time at pH < 4 in the first hour after ingestion of 300 ml white wine (median 13.2%) was significantly increased compared with beer (3.6%; P < 0.01), water (0.9%; P < 0.001), ethanol (1.3%; P < 0.001), and the nonalcoholic beverage (0.9%; P < 0.05). Beer provoked significantly more gastroesophageal reflux than water (P < 0.01). It is concluded that white wine and beer induce gastroesophageal reflux, which is neither related to their ethanol content nor to their pH. The mechanism for this effect remains to be identified.
Adult↗
Effect of jejunal infusion of different caloric loads on pancreatic enzyme secretion and gastro-intestinal hormone response in man.
It has recently been demonstrated that the infusion of a high caloric load (3.3 kcal min-1 = 14.0 kJ min-1) into human upper jejunum inhibited pancreatic enzyme and bile salt secretion. The aim of the present study was to investigate whether this phenomenon was mediated by gastrointestinal hormones which interfere with pancreatic secretion. In six healthy volunteers, jejunal infusion of 1.3 kcal min-1 (5.5 kJ min-1) did not modify secretion of lipase and chymotrypsin to any significant extent compared with saline infusion, but the rate of 3.3 kcal min-1 (14.0 kJ min-1) resulted in an inhibition. Somatostatin and pancreatic polypeptide, which are known to inhibit exocrine pancreatic secretion, remained unchanged during jejunal nutrient infusion. The inhibition of pancreatic enzyme secretion was observed in temporal relationship with an increase of the stimulators of pancreatic exocrine secretion such as secretin, neurotensin, and CCK. The existence of an hitherto undefined inhibitor and a feedback mechanism is postulated.
Adult↗