Search PubMed⌕ Search

Biomedical subjects

H Ditschuneit

Publications and source records attributed to H Ditschuneit.

At least 109 records · Page 6Linked to original sources
PubMed1987

Fluorescein dilaurate serum test: a rapid tubeless pancreatic function test.

The value of a modified fluorescein dilaurate (FDL) serum test for the detection of pancreatic exocrine insufficiency was investigated in 89 patients with and without pancreatic disease. This test modification with fluorescein serum determination following metoclopramide (10 mg) and secretin (1 U/kg) i.v. injection appeared efficacious in a pilot study in six healthy volunteers. Individual peak fluorescein serum concentration was achieved within 180 min after the test meal in 96% of all subjects studied. Peak fluorescein serum concentration within this time period allowed the best discrimination between normal and abnormal pancreatic function. Sensitivity in detection of chronic pancreatitis was 86% (38 of 44 patients) when the lower normal fluorescein serum concentration was considered 4.5 micrograms/ml (this value corresponds to mean - 2 SD). The specificity of this test in detecting chronic pancreatitis was 100% when healthy controls were considered, but fell to 78% when patients with different gastrointestinal disorders, including those with secondary pancreatic insufficiency, were included. The correlation between serum and urinary fluorescein determination was significant (r = 0.61; p less than 0.01). Duodenal bicarbonate output/h after secretin also showed a significant correlation with peak fluorescein serum concentration (r = 0.79; p less than 0.001).

Adolescent↗
PubMed1987

Adaptive changes of the exocrine pancreas and plasma cholecystokinin release following subtotal gastric resection in rats.

This study was performed to investigate adaptive changes of the exocrine pancreas occurring after distal gastric resection by different procedures: Billroth I (BI) and Billroth II (BII). Sixty-four male Wistar rats were used and divided into four groups: controls (n = 16), sham-operated (n = 16), BI (n = 16) and BII (n = 16) subtotal gastric resection. Both procedures of subtotal gastric resection showed an organotrophic effect on the pancreas after 2 weeks: pancreatic weight in BI- and BII-operated rats increased by 23 and 35% and DNA content by 36 and 27%, respectively, compared to controls (p less than 0.001). After 4 weeks a further increase in pancreatic weight (46%), DNA content (52%) and protein content (58%) was found in BII rats. Trypsin and amylase content were increased in BI rats after 2 weeks (p less than 0.01). No parallel changes were observed in the enzyme content of BII rats as trypsin increased by over 200%, amylase by over 100% and lipase remained unaffected. Hormonal studies were carried out in 36 rats divided into groups as above. Basal and stimulated plasma levels of gastrin were reduced (p less than 0.01) following both types of subtotal gastric resection (p less than 0.01). Basal cholecystokinin (CCK) plasma levels did not differ between operated and control rats. Following the test meal CCK plasma levels were significantly increased after BII gastric resection (p less than 0.001) and BI gastric resection (p less than 0.01) compared to controls.

Amylases↗
PubMed1987

Interaction of receptors for insulin-like growth factor I, platelet-derived growth factor, and fibroblast growth factor in rat aortic cells.

Serum contains various growth factors which regulate the proliferation of cells. We investigated the growth of cultured arterial smooth muscle cells under the influence of insulin-like growth factor I (IGF I), fibroblast growth factor (FGF), and platelet-derived growth factor (PDGF), and examined the effect of these growth factors on the binding of [125I] IGF I and on the binding of [125I]PDGF to these cells. IGF I, FGF, and PDGF stimulated [6-3H]thymidine incorporation into DNA of confluent cultures of cells which were incubated in modified Dulbecco's modified Eagle medium. However, the effect of these growth factors on DNA synthesis was much more potent in Dulbecco's modified Eagle medium with 1% fetal calf serum. FGF and PDGF potentiated the growth-promoting effect of IGF I. The binding of [125I]IGF I to the cells was increased after a preincubation with FGF and PDGF. The binding was potently increased by FGF (100 ng/ml) after a preincubation time of 30 min. There was an increase in binding during the first 3 h of preincubation followed by a decrease after 4-5 h. PDGF (10-1000 ng/ml) stimulated [125I]IGF I binding only after 2 h of preincubation. The stimulation was dose dependent. Maximal stimulation of the binding was observed after 3 h of preincubation followed by a decrease after 4-5 h of preincubation. Specific binding sites for PDGF on smooth muscle cells could be demonstrated too. A preincubation of confluent cells with IGF I caused a dose-dependent increase in [125I]PDGF binding. These results support the hypothesis that the regulation of the binding of a specific growth factor by a second growth factor is important for the control of cell growth.

Animals↗
PubMed1987

Influence of increased fibre intake on biliary lipids.

Influence of increased fibre intake on biliary lipids. The influence of dietary fibres (30 g wheat bran per day) on the lithogenicity of the bile was studied in ten healthy persons, whose body weight was 76.8 +/- 2.3 kg, height 189.9 +/- 2.1 cm, age 25.5 +/- 0.26 years. These 10 young male volunteers were given twice daily 15 g wheat bran additionally for six weeks in addition to their normal diet. The bile was obtained endoscopically prepapillarily following stimulation of the gallbladder with ceruletid. The contraction of the gallbladder was controlled sonographically. Increased dietary fibre intake resulted in significant lowering of cholesterol concentration in the bile from 3.27 +/- 0.89 mmol/1 to 2.50 +/- 0.67 mmol/1. The lithogenic index (Admirand and Small, 1968) decreased statistically significant from 1.01 +/- 0.14 to 0.67 +/- 0.11. Total cholesterol and HDL and LDL cholesterol remained unchanged; likewise, there was no change in serum triglyceride and phospholipid concentrations. Hence, an increased intake of dietary fibres of the wheat bran type should be the first dietary measure in both prevention and treatment of cholesterol gallstone disease.

Adult↗
PubMed1987

[Regulation of endogenous prostaglandin synthesis in the upper gastrointestinal tract].

Prostaglandins are involved in many physiological functions of the gastrointestinal tract, e.g. the secretion of acid, mucus and bicarbonate, the motility, the microcirculation and cytoprotection. The diverse prostaglandins as well as prostacyclin and thromboxane are synthesized by a complex enzymatic system, which is affected by a multitude of possibly regulatory influences. Such mechanisms are the availability of dietary essential fatty acids, the calcium, dependent activation of the phospholipase A2, the self-inactivation of the prostaglandin cyclooxygenase, the availability of cofactors, the catabolism of the prostanoids and others. A minireview concerning these potentially regulatory mechanisms in the upper gastrointestinal tract is presented.

Animals↗
PubMed1987

[Prostaglandin synthesis in stomach and duodenal mucosa of the human: effect of aspirin with and without antacid].

A decreased PG E2 content in gastric mucosa of humans receiving a longterm antirheumatic therapy has been reported to be partially reversed after a one week treatment with an antacid (Reimann et al., Fortschr Med 102 [1984], 25-26). Therefore the effect of an Aspirin treatment of healthy volunteers with or without an antacid on the prostaglandin synthesis in gastric or duodenal mucosa was investigated. 14C-labelled arachidonic acid was used as substrate during in vitro incubation of the mucosal homogenate for determination of the endogenous formation of prostaglandins. Aspirin suppressed the total prostaglandin synthesis to less than 10% of control after one week treatment. The addition of a high dose antacid did not influence this inhibition, and no significant effect on the prostaglandin profile was detectable. It is concluded that antacids do not influence the suppression of the endogenous prostaglandin synthesis by NOSAC's, however another effect, eg a prolonged stability of PG E2 in a less acidic environment is more likely.

Adult↗
PubMed1987

Insulin as a growth regulator of arterial smooth muscle cells: effect of insulin of I.G.F.I.

The proliferation of smooth muscle cells in the vessel wall plays an important role in the development of an atherosclerosis. The insulin-like growth factor I (I.G.F.I) is an important growth factor for cultivated arterial smooth muscle cells. The plasma I.G.F.I level is controlled by growth hormone and insulin--both factors seem to be important for the development of a diabetic macroangiopathy. In order to evaluate whether I.G.F.I is associated with the development of a macroangiopathy we measured the serum I.G.F.I level in type 2 diabetics with and without macroangiopathy and in non diabetic patients with atherosclerosis and in healthy controls. The range of the individual I.G.F.I levels was wide and the I.G.F.I level between the various groups was not statistically significant. However, our studies with cultured cells show that modulation of the cellular responsiveness to I.G.F.I is as important in the growth control as are changes in the plasma I.G.F.I level. We observed that cultured smooth muscle cells were able to produce an I.G.F.I-like factor. The synthesis and secretion of this factor was dependent on insulin. These findings explain one mechanism by which insulin may influence the growth of smooth muscle cells in the vessel wall.

Adult↗
PubMed1987

[Campylobacter pylori in duodenal ulcer--a concomitant phenomenon or causal association?].

The rediscovery of spiral bacteria in gastric mucosa in recent years has given raise to new speculations concerning the pathogenesis of peptic ulcer disease. Due to the features and localisation of this bacterium it was named campylobacter pylori. Findings pointing to a pathogenetic role of this bacterium are few and not definitely settled. The frequency of campylobacter on the gastroduodenal mucosa, its short term survival in acidic environment, its extraordinary mobility and content of specific enzymes makes it likely that this bacterium exerts a noxious effect on the gastroduodenal mucosa. Moreover a local and systemic immune response caused by campylobacter has been reported. We performed ultrastructural investigations on duodenal mucosa in patients with active peptic ulcer disease. An ultrastructural localization of the bacterium in duodenal mucosa of these patients was possible in 40%. Campylobacter pylori is localized preferentially on metaplastic cells of the antrum type, is seen penetrating in the intercellular spaces and is found also included in vacuoles of epithelial cells. These findings raise the hypothesis that campylobacter pylori infection can lead to direct damage of duodenal mucosa.

Bacteriological Techniques↗
PubMed1987

[Lithogenicity and bile acid pattern in choleretic administration (3-n-butoxy-1-phenoxy-propanol: febuprol) in patients with functional right upper quadrant pain].

10 patients with right upper quadrant pain were treated with a choleretic agent (Febuprol; 3 X 200 mg t. i. d.) and placebo in a cross-over double dummy technique for 16 weeks. Lithogenic index, bile acid profile and serum lipids were determined every 4 weeks. During Febuprol application the clinical symptoms were relieved (0.87 +/- 1.3 vs. 1.39 +/- 0.21 (placebo); p less than 0.05, semiquantitative score). Biliary lithogenicity (1.45 +/- 0.6 vs. 1.09 +/- 0.12; n. s.), bile acid profile and serum lipids showed no statistically significant change, although serum cholesterol levels seemed to fall during Febuprol application.

1-Propanol↗
PubMed1987

[The fluorescein dilaurate serum test following metoclopramide and secretin stimulation for evaluating pancreatic function. Contribution to the diagnosis of chronic pancreatitis].

A new method of exocrine pancreatic function testing is described. After oral administration of a standard meal containing fluorescein dilaurate (FDL) metoclopramide (10 mg) and secretin (1 U/kg) are given as intravenous bolus injection. The best discrimination between normal and abnormal pancreatic function was found to be the individual peak serum fluorescein concentration within 180 minutes. 184 patients were studied and divided into 4 groups according to the final diagnosis: group 1: 44 healthy controls; group 2: 87 patients with chronic pancreatitis; group 3: 21 patients with different pancreatic diseases; group 4: 32 patients with different gastrointestinal disorders. Sensitivity of the FDL serum-test in detecting chronic pancreatitis was 87%, specificity was 97%. Considering patients with different gastrointestinal disorders specificity dropped to 77%. FDL serum-test revealed superior as compared to the FDL urine test. Correlation between FDL serum-test and secretin ceruletide test was significant (r = 0.72, p less than 0.001).

Chronic Disease↗
PubMed1987

[Ultrastructural aspects of active and healed duodenal ulcer].

To characterize the fine structure of active and healed duodenal ulcers, tissue specimens of patients with active duodenal ulcer disease were examined under two different treatment schedules by various electron microscopic techniques. The striking histological feature of both, the active and healed duodenal ulcer, was the appearance of PAS-positive epithelial cells. Electron microscopy revealed similarity to a special type of mucus secreting cell of the antrum. The destroyed mucous structure during the ulcerative phase regains the normal net-like structure after treatment. The ultrastructural healing process shows constant features independent from the type of treatment and shows that the repair mechanisms are incomplete after a 4 week treatment.

Biopsy↗
PubMed1986

Effect of down-regulation and return of insulin receptors on glycogen synthesis in cultured rat hepatocytes.

The dependence of the regulation of insulin receptors by insulin on the time hepatocytes were maintained in culture and the relationship between the return of down-regulated receptors and glycogen synthesis from labelled glucose were investigated in primary cultures of adult rat hepatocytes. Insulin receptor numbers, but not ligand affinity, decreased significantly within the first 24 h of culture, even in the absence of insulin, and then returned to the immediate 'post-attachment' level during 24-48 h. Therefore, down-regulation of insulin receptors by 10 nmol/l insulin was only minor during the 1st day in culture, but amounted to 50% of control levels after the 2nd day, whereas the rate of insulin degradation remained unaltered throughout the entire period of culture. When down-regulated monolayers were switched to insulin-free medium, receptors returned to control levels within 5-10 h. The reduced basal rate of glycogenesis as well as insulin-sensitivity and insulin responsiveness of this metabolic pathway also gradually increased to control levels. However, the time-dependent receptor return was dissociated from the increase in insulin-sensitivity, emphasising the importance of postbinding events. Since the changes both in basal rates and in insulin responsiveness of glycogenesis during the period of receptor return were inversely related to differences in the actual glycogen content between control and down-regulated cells, cellular glycogen content might participate in the regulation of glycogenesis as a 'feedback inhibitor'.

Animals↗
PubMed1986

Insulin binding to cultured adult hepatocytes. Effects of bacitracin and chloroquine on the nature of cell-associated radioactivity.

Sephadex (G-50 fine grade)-gel chromatography and trichloroacetic acid (TCA) precipitation were used to investigate the effects of chloroquine and bacitracin on the nature of cell-associated radioactivity in studies on the binding and degradation of 125I-insulin in cultured rat hepatocytes. Sephadex peak I, eluted with the void volume, increased with hepatocyte incubation time and comprised 6% of total cell-bound radioactivity at 120 min. However, all radioactivity in this peak was due to unspecific binding. Peak II, corresponding to intact insulin, represented 95% of specifically cell-associated label at 5 min and decreased to 77% at 120 min. Peak III, containing the final low-Mr degradation products, increased with incubation time (22% of specifically bound label at 120 min). The TCA-precipitable and TCA-soluble fractions of hepatocytes extracted with 0.1% SDS were within 4-7% of the proportions of radioactivity in peaks II and III respectively. Scatchard plots based on insulin-binding data from Sephadex chromatography or TCA precipitation were identical. Dissociation studies revealed that at least 75% of the intact insulin associated with the hepatocytes was bound to receptors at the cell surface. Bacitracin increased the proportion of cell-associated intact hormone and decreased that of ligand degraded when analysed by either Sephadex chromatography or TCA precipitation. The proportion of surface-bound to internalized intact hormone remained unaltered, indicating that bacitracin acted predominantly at the cell surface. In the presence of chloroquine, which dramatically increased the contribution of peak I to specific binding, 'intact' insulin was substantially overestimated when determined as the TCA-precipitable fraction. In addition, all peak I material and 50% of cell-associated label in peak II was trapped intracellularly, thereby pointing to the lysosomal or prelysosomal site of action of this drug.

Animals↗
PubMed1986

Influence of triamcinolone and somatostatin on morphometric parameters of cultured intestinal mucosa.

Mucosal biopsies from rabbit ileum were organ cultured for 24 h. The influence of triamcinolone and somatostatin on villus height and diameter as well as crypt depth and the number of mitoses was measured at various times during 24 h of culture as indices of cell proliferation and tissue maintenance. It could be shown that triamcinolone reduced cell proliferation slightly but preserved mucosal structure in organ culture. Somatostatin inhibited crypt cell proliferation, without any effect on other morphological parameters.

Animals↗
PubMed1986

Real-time ultrasound evaluation of renal transplant failure during the early postoperative period.

In a prospective clinical trial 385 ultrasound (US) examinations were performed on 50 renal allograft patients. Baseline sonograms were obtained within 24 hrs of transplantation, and serial US examinations were performed in two to three days intervals during hospital recovery. 24 out of 28 cases of acute rejections (85.7%) were detected by US with an 8% false positive rate. Using statistical analysis, enlarged and sonolucent pyramids, areas of decreased parenchymal echogenicity and an increase in anterior-posterior diameter of the organ, proved to be the best US-rejection criteria. Fine needle aspiration cytology revealed a high rate of false positive rejection diagnosis (23.8%). The results demonstrate that US is a valuable diagnostic aid in the evaluation of postoperative renal transplant failure.

Adult↗
PubMed1986

Hepatic regenerative stimulator substance in the rabbit. Relation to liver regeneration after partial hepatectomy.

The occurrence and activity of hepatic regenerative stimulator substance was investigated in the partially hepatectomized rabbit and related to biochemical and morphological parameters of liver regeneration. Male rabbits were 60% hepatectomized by excising the Spigelian, left lateral and left central lobes of the liver leaving the gallbladder in situ. [3H]Thymidine incorporation into DNA, the fraction of labelled hepatocyte nuclei, the fraction of mitoses and thymidine kinase activity rose from basal levels at 30-40 h after hepatectomy and increased up to 12-fold at 40-60 h. After 7 days, proliferation parameters returned to near prae-hepatectomy values and 82% of the initial liver mass was restored. Hepatic regenerative stimulator substance was biologically active when prepared from rabbit livers between 18-30 h after partial hepatectomy. At 12 and 30 h after intraperitoneal injection of the extract into normal rats, hepatic DNA synthesis was stimulated up to 2-fold in a dose-dependent fashion. The biological activity was protease-sensitive and thus depended on a protein component of the extract. The data demonstrate the existence of hepatic regenerative stimulator substance in regenerating rabbit liver and suggest that it is implicated in the regulation of liver growth after partial hepatectomy.

Animals↗
PubMed1986

[Results of sonographic diagnosis of choledochal calculi].

To evaluate sonographic accuracy in the diagnosis of choledochal calculi 44 patients were examined prospectively with a mechanical sector scanner before endoscopic retrograde cholangiography (ERC). Calculi with a diameter of more than 1.5 cm could be detected in all cases. Smaller stones (less than 1 cm) were missed in 50% of cases. To quantitate sensitivity in daily clinical practice, the data of 229 patients, suspected to have common bile duct stones, were analysed retrospectively. The overall accuracy was 76%, 90% when an experienced sonographer performed the examination and 47% if the examiner was less experienced. From these data it is concluded that the sonographic detection of choledochal calculi is influenced by the examination technique, experience of the examiner and diameter of the stones.

Adult↗