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W Creutzfeldt

Publications and source records attributed to W Creutzfeldt.

At least 19 recordsLinked to original sources
PubMed2003

A 25-year follow-up study of glucose tolerance in first-degree relatives of type 2 diabetic patients: association of impaired or diabetic glucose tolerance with other components of the metabolic syndrome.

A follow-up study of first-degree relatives of type 2 diabetic patients presented the opportunity to study the association of components of the metabolic syndrome with oral glucose tolerance in these subjects. In 1992, 25 years after the first analysis of the cohort, we performed 75-g oral glucose tolerance tests and measured anthropometric data (body mass index, waist-hip ratio), insulin and C-peptide concentrations, and parameters of lipoprotein metabolism (free fatty acids, triglycerides, cholesterol, HDL cholesterol). Of 135 participants, 71 had normal glucose tolerance (GT), 22 had impaired GT, and 42 had diabetic GT (WHO 1985 criteria). Impaired glucose tolerance and diabetes were significantly (Kruskal-Wallis test) associated with advanced age (p=0.001), higher body mass index (p=0.005) and waist-hip ratio (p=0.027), systolic hypertension (p=0.031), elevated basal insulin concentrations (p<0.001), higher free fatty acids (p<0.001) and triglycerides (p=0.017), and lower HDL cholesterol (p=0.003); no associations were found with total and LDL cholesterol levels (Friedewald's formula, p=0.25). Abnormalities (obesity, hypertriglyceridemia, low HDL cholesterol, hypertension, pathological oral glucose tolerance) were associated with significant deterioriations in all other components of the metabolic syndrome, if their number exceeded three. Disturbances of oral glucose tolerance are present in a high percentage of first-degree relatives after 25 years of follow-up (51% of those tested). Impaired or diabetic glucose tolerance in such a cohort was associated with overweight, hypertension and disturbances of lipoprotein metabolism characteristic of the metabolic syndrome. Hypercholesterolemia (LDL-cholesterol) is not a component of the metabolic syndrome in a German population with a high hereditary burden regarding type 2 diabetes. A metabolic syndrome should certainly be diagnosed if three components are present, although even in the presence of only two components, an elevated risk is evident.

Aged↗
PubMed2001

The entero-insular axis in type 2 diabetes--incretins as therapeutic agents.

The search for intestinal factors regulating the endocrine secretion of the pancreas started soon after the discovery of secretin, i.e. nearly 100 years ago. Insulinotropic factors of the gut released by nutrients and stimulating insulin secretion in physiological concentrations in the presence of elevated blood glucose levels have been named incretins. Of the known gut hormones only gastric inhibitory polypeptide (GIP) and glucagon-like polypeptide-1 (GLP-1 [7-36] amide) fulfill this definition.--The incretin effect (i.e. the ratio between the integrated insulin response to an oral glucose load and an isoglycaemic intravenous glucose infusion) is markedly diminished in patients with type 2 diabetes mellitus, while the plasma levels of GIP and GLP-1 and their responses to nutrients are in the normal range. Therefore, a reduced responsiveness of the islet B-cells to incretins has been postulated. This insensitivity of the diabetic B-cells towards incretins can be overcome by supraphysiological (pharmacological) concentrations of GLP-1 [7-36], however not of GIP. Accordingly, fasting and postprandial glucose levels can be normalized in patients with type 2 diabetes by infusions of GLP-1 [7-36]. Further studies revealed that this is partially due to the fact that GLP-1 [7-36]--in addition to its insulinotropic effect--also inhibits glucagon secretion and delays gastric emptying. These three antidiabetic effects qualify GLP-1 [7-36] as an interesting therapeutic tool, mainly for type 2 diabetes. However, because of its short plasma half life time natural GLP-1 [7-36] is not suitable for subcutaneous application. At present methods are being developed to improve the pharmacokinetics of GLP-1 by inhibition of the cleaving enzyme dipeptidyl peptidase IV (DPP-IV) or by synthesis of DPP-IV resistant GLP-1 analogues. Also naturally occurring GLP-1 analogues (for instance exendin-4) with a much longer half life time than GLP-1 [7-36] are being tested.--Thus, after 100 years of speculations and experimentations, incretins and their analogues are emerging as new antidiabetic drugs.

Animals↗
PubMed2001

The rise of gastrointestinal endocrinology since 1970 and Jens F. Rehfeld and his group right in the middle of it.

The scientific achievements of Jens F. Rehfeld, and the impact of the contributions of Jens Rehfeld and his coworkers on our knowledge of gut-brain peptides is reviewed, based on almost 30 years of scientific contact and friendship. The identification of the first gut peptides led to the "immunologic era" and subsequently to the "genetic" era, during which cascades of new knowledge have been generated.

Congresses as Topic↗
PubMed2000

[Chiral switch, a successful way for developing drugs: example of esomeprazole].

About 25% of common drugs are racemates, i.e. mixtures of their optical or spatial isomers (stereoisomers or enantiomers). Frequently the enantiomers differ in their pharmacokinetics, pharmacodynamics, drug interactions and side effects. Therefore, the pharmaceutical industry, pharmacologists and clinicians are increasingly interested in the development of enantiomers as drugs. Since advances in synthetic and analytical chemistry have provided the tools to produce stereoisomeric drugs, also the authorities recommend and support chiral switch. As example for the therapeutic gain the recent studies with esomeprazole, the first isomeric protonpump inhibitor (iPPI) are summarized and discussed.

Anti-Ulcer Agents↗
PubMed1999

[Consensus conferences and guidelines in gastroenterology: an illusion].

Evidence-based medicine describes the present-day situation of a rational medicine which has its origins in the 19th century. At present evidence-based medicine is an ideal which is unattainable due to inadequate data from randomised controlled studies. Guidelines and consensus conferences which are not based on clearcut scientific data from controlled prospective and randomised studies fail to meet the requirements of evidence-based medicine and so cannot improve patient management. Guidelines and consensus conferences do not substantially reduce health costs.

Consensus Statements as Topic↗
PubMed1998

Electron-microscopical evidence for heterogeneity of micronodular argyrophil cell growth in man.

Hypergastrinaemia-associated changes of non-antral argyrophil cells in man are of increasing interest, because of the development of potent inhibitors of gastric acid secretion. Using an antibody against chromogranin A, we identified micronodular endocrine cell hyperplasia of the oxyntic mucosa in gastric biopsy specimens of patients with hypergastrinaemia of different backgrounds. Consecutive ultrathin sections were examined at the electron-microscopical level. Endocrine cell types within the (extraepithelial) micronodules closely resembled those in the adjacent mucosa. Micronodules were classified into two groups. The first group was composed of endocrine cells only and predominated in patients with drug-induced hypergastrinaemia and/or chronic gastritis, and in a gastrinoma/MEN I patient. The second group represented "neuroendocrine complexes", showing a close intermingling of non-myelinated nerve fibres with endocrine cells, and was found predominantly in pernicious anaemia. Micronodular argyrophil cell growth in man is therefore heterogeneous and depends on the background of the hypergastrinaemia.

Anemia, Pernicious↗
PubMed1998

Overnight GLP-1 normalizes fasting but not daytime plasma glucose levels in NIDDM patients.

GLP-1 (7-36 amide) normalizes fasting plasma glucose in NIDDM patients. It was the aim to study the effect of overnight intravenous GLP-1 (7-36 amide) on the following 24 h-glucose profiles. Ten NIDDM patients (7 female, 3 male; age 62 +/- 4 y., BMI (Body-Mass-Index) 29.6 +/- 3.9 kg/m2, duration 10 +/- 7 y., HbA1c 10.9 +/- 1.3% (normal 4.0-6.1%), treated with glibenclamide and/or metformin) were studied on two occasions in random order: Either GLP-1 (7-36 amide) (Saxon Biochemicals, Hannover, FRG, 1 pmol x kg(-1) x min(-1)) or placebo (0.9% NaCl with 1% human serum albumin, Behringwerke, Marburg, FRG) were infused intravenously from 22:00 to 7:00 (9 h) and plasma glucose profiles were obtained during the GLP-1 infusion and the following 24 hours. GLP-1 (7-36 amide) (plasma concentration 110 +/- 12 pmol/l) raised plasma C-peptide concentrations (p = 0.0005), suppressed glucagon (p = 0.01) and lowered plasma glucose to 5.5 +/- 0.6 and 6.3 +/- 0.4 mmol/l at 3:00 and 7:00 a.m. (vs. 10.3 +/- 0.9 and 11.3 +/- 0.6 mmol/l, p = 0.0003 and p < 0.0001, respectively, with placebo). Thereafter, starting 1 h after breakfast, no significant differences in plasma glucose, insulin, C-peptide or glucagon profiles were found between experiments with GLP-1 (7-36 amide) and placebo. Average plasma glucose concentrations over the whole 24 h period were reduced by 18% by GLP-1 administered overnight. In conclusion, (1) overnight GLP-1 (7-36 amide) normalizes fasting plasma glucose, but (2) has no sustained effect on meal-induced glucose, insulin or glucagon concentrations once its administration has been stopped. (3) Normalization of fasting plasma glucose alone does not improve daytime metabolic control in NIDDM patients on oral agents.

Aged↗
PubMed1997

Early ERCP and papillotomy compared with conservative treatment for acute biliary pancreatitis. The German Study Group on Acute Biliary Pancreatitis.

BACKGROUND: The role of early endoscopic retrograde cholangiopancreatography (ERCP) and papillotomy in the treatment of patients who have acute biliary pancreatitis without obstructive jaundice is uncertain. METHODS: We conducted a prospective, multicenter study in which 126 patients were randomly assigned to early ERCP (within 72 hours after the onset of symptoms) and endoscopic papillotomy for the removal of stones in the common bile duct, when appropriate, and 112 patients were assigned to conservative treatment. In the conservative-treatment group, ERCP was performed within three weeks if signs of biliary obstruction or sepsis developed. Overall mortality, mortality due to pancreatitis, and complications were compared in the two groups. RESULTS: Early ERCP was successful in 121 of the 126 patients in the invasive-treatment group. Endoscopic papillotomy was performed to remove bile-duct stones in 58 patients; stones were successfully extracted in 57. ERCP was performed in 22 of the 112 patients in the conservative-treatment group; papillotomy for stone removal was successful in 13 patients. Fourteen patients in the invasive-treatment group and 7 in the conservative-treatment group died within three months (P=0.10); 10 patients in the invasive-treatment group and 4 in the conservative-treatment group died from acute biliary pancreatis (P=0.16). The overall rate of complications was similar in the two groups, but patients in the invasive-treatment group had more severe complications. Respiratory failure was more frequent in the invasive-treatment group, and jaundice was more frequent in the conservative-treatment group. CONCLUSIONS: In patients with acute biliary pancreatis but without obstructive jaundice, early ERCP and sphincterotomy were not beneficial.

Acute Disease↗
PubMed1997

A hyperinsulinaemic, sequentially eu- and hypoglycaemic clamp test to characterize autonomous insulin secretion in patients with insulinoma.

To better characterize autonomous insulin secretory behaviour in insulinoma patients and to establish diagnostic criteria with high accuracy, hyper-insulinaemic, sequentially eu- and hypoglycaemic clamp tests were performed in insulinoma patients and control subjects. Ten patients with insulinoma (benign in nine, histologically proven in nine) and 10 patients with suspected episodes of hypoglycaemia, in whom thorough clinical evaluation excluded an insulinoma, were examined. Five insulinoma patients were restudied after successful extirpation of the tumour. Suppression of C-peptide during low-dose [2 pmol kg-1 min-1 (20 mU kg-1 h-1) for 90 min, plasma insulin approximately 120 pmol L-1 (20 mUL-1)] and high-dose [8 pmol kg-1 h-1 (80 mU kg-1 h-1) for 90 min, plasma insulin approximately 450 pmol L-1 (75 mU L-1)] insulin infusion under euglycaemic conditions [plasma glucose 4.4-5.0 mmol L-1 (80-90 mg dL-1)] and during high-dose insulin infusion under hypoglycaemic conditions [glucose 2-2.2 mmol L-1 (40-45 mg dL-1)] was evaluated by radioimmunoassay (RIA). Euglycaemic hyper-insulinaemia suppressed C-peptide in control subjects (P < 0.0001), whereas in insulinoma patients apparently irregular changes in C-peptide concentrations (with spontaneous or paradoxical increments, P = 0.0006 vs. controls) were observed. The combination of hyper-insulinaemia and controlled hypoglycaemia led to a nearly complete suppression of C-peptide in normal subjects (from basal, 0.76 +/- 0.08-0.06 +/- 0.01 nmol L-1; maximum observed value 0.10 nmol L-1), which was more pronounced than at the point of discontinuation of prolonged fasting (> 48 h; 0.26 +/- 0.16 nmol L-1; P = 0.005). In insulinoma patients, C-peptide remained elevated under all conditions (P = 0.51 vs. prolonged fasting). All these findings were reversible after successful surgical removal of the insulinoma. Insulinoma patients could be identified as abnormal by (a) non-suppression of C-peptide even under hyperinsulinaemic/hypoglycaemic conditions (10 out of 10 patients) and (b) irregular increments in C-peptide under conditions that led to at least partial suppression in all normal subjects (9 out of 10 patients) and/or by an apparent shift to the left of insulin secretion relative to glucose concentrations (7 out of 10 patients). Controlled exposure to hyperinsulinaemic/hypoglycaemic conditions can help to characterize autonomous secretion in insulinoma patients and may be used as a diagnostic procedure when conventional methods yield equivocal results.

Adult↗
PubMed1996

Effects of subcutaneous glucagon-like peptide 1 (GLP-1 [7-36 amide]) in patients with NIDDM.

Intravenous glucagon-like peptide (GLP)-1 [7-36 amide] can normalize plasma glucose in non-insulin-dependent diabetic (NIDDM) patients. Since this is no form for routine therapeutic administration, effects of subcutaneous GLP-1 at a high dose (1.5 nmol/kg body weight) were examined. Three groups of 8, 9 and 7 patients (61 +/- 7, 61 +/- 9, 50 +/- 11 years; BMI 29.5 +/- 2.5, 26.1 +/- 2.3, 28.0 +/- 4.2 kg/m2; HbA1c 11.3 +/- 1.5, 9.9 +/- 1.0, 10.6 +/- 0.7%) were examined: after a single subcutaneous injection of 1.5 nmol/kg GLP [7-36 amide]; after repeated subcutaneous injections (0 and 120 min) in fasting patients; after a single, subcutaneous injection 30 min before a liquid test meal (amino acids 8%, and sucrose 50 g in 400 ml), all compared with a placebo. Glucose (glucose oxidase), insulin, C-peptide, GLP-1 and glucagon (specific immunoassays) were measured. Gastric emptying was assessed with the indicator-dilution method and phenol red. Repeated measures ANOVA was used for statistical analysis. GLP-1 injection led to a short-lived increment in GLP-1 concentrations (peak at 30-60 min, then return to basal levels after 90-120 min). Each GLP-1 injection stimulated insulin (insulin, C-peptide, p < 0.0001, respectively) and inhibited glucagon secretion (p < 0.0001). In fasting patients the repeated administration of GLP-1 normalized plasma glucose (5.8 +/- 0.4 mmol/l after 240 min vs 8.2 +/- 0.7 mmol/l after a single dose, p = 0.0065). With the meal, subcutaneous GLP-1 led to a complete cessation of gastric emptying for 30-45 min (p < 0.0001 statistically different from placebo) followed by emptying at a normal rate. As a consequence, integrated incremental glucose responses were reduced by 40% (p = 0.051). In conclusion, subcutaneous GLP-1 [7-36 amide] has similar effects in NIDDM patients as an intravenous infusion. Preparations with retarded release of GLP-1 would appear more suitable for therapeutic purposes because elevation of GLP-1 concentrations for 4 rather than 2 h (repeated doses) normalized fasting plasma glucose better. In the short term, there appears to be no tachyphylaxis, since insulin stimulation and glucagon suppression were similar upon repeated administrations of GLP-1 [7-36 amide]. It may be easier to influence fasting hyperglycaemia by GLP-1 than to reduce meal-related increments in glycaemia.

Adult↗
PubMed1996

Carcinoid tumors: development of our knowledge.

Historically, carcinoids have long been known to be a morphologically distinct class of rare intestinal tumors that behave less aggressively than the more common intestinal adenocarcinomas. It was not until much later that their endocrine nature was recognized. Some authors restrict the term carcinoid to intestinal endocrine tumors, whereas others include a large variety of neuroendocrine tumors. In the WHO classification of 1980, carcinoids were defined as tumors of the diffuse neuroendocrine system that are either benign or neoplasms with a more favored prognosis than carcinomas. They are characterized by a typical growth pattern, silver affinity, and positive immunohistochemical reaction with neuron-specific markers; and they can express different peptides and biogenic amines. Neuroendocrine tumors originating from endocrine glands (pituitary, thyroid, adrenals, pancreas) and highly malignant neuroendocrine carcinomas are excluded from the carcinoid group of neoplasms. For the natural history of carcinoid tumors several independent predictive parameters can be defined: size, site of origin, growth pattern, and hormone dependence. The number of neuropeptides and amines expressed by a carcinoid or the amount of biologically active neurohormones secreted are of no prognostic significance regarding malignant behavior. The carcinoid syndrome is a rare clinical entity that occurs with a prevalence of 1.6% for carcinoid tumors and almost only if liver metastases are present. The complex clinical symptoms are only partially explained by the secretion of serotonin and tachykinins.

Biogenic Amines↗
PubMed1996

Secretin-pancreozymin test (SPT) and endoscopic retrograde cholangiopancreatography (ERCP): both are necessary for diagnosing or excluding chronic pancreatitis.

Results of the SPT and the ERCP staged for their severity were compared in 202 patients. The correlation between both investigations was significant (p < 0.001); however, ERCP showed significantly more severe changes (p = 0.04). Furthermore, we found that 129 (64%) patients had parallel SPT and ERCP results, matching in all four gradings of severity. Forty-three (21%) patients had abnormal results for both SPT and ERCP, but the severity gradings did not parallel. Finally, 30 (15%) patients showed totally nonparallel results, a normal SPT and abnormal ERCP, or vice versa. Abnormal ERCP but normal SPT results were found in 23 of these 30 patients (group 1), and normal ERCP but abnormal SPT results in the seven remaining cases (group 2). In the first group, more patients had a history of acute pancreatitis compared to the second group (19 vs. one, p < 0.005). Based on medical history, laboratory and functional test results, and other morphological tests, chronic pancreatitis was diagnosed in two of 23 patients in group 1 and in all seven patients in group 2. Follow-up interviews (86 +/- 54 months) were possible in 20 of the remaining 21 patients in group 1 and showed definite chronic pancreatitis in one and probable chronic pancreatitis in another two of them, whereas in the other 17 patients no symptoms of acute pancreatitis or abdominal pain suggestive of chronic pancreatitis had occurred. In conclusion, both SPT and ERCP should be used to complement each other when chronic pancreatitis is suspected. ERCP seems to over-diagnose the disease since duct changes may only reflect scars after severe acute pancreatitis, or old age, and are not necessarily a sign of chronic pancreatitis. SPT seems to diagnose chronic pancreatitis with more reliability.

Adult↗
PubMed1996

Somatostatin analogue octreotide and inhibition of tumour growth in metastatic endocrine gastroenteropancreatic tumours.

Antiproliferative treatment of patients with metastatic endocrine gastroenteropancreatic tumours (GEP) is based mainly on chemotherapeutic protocols whereby drug toxicity is a major handicap. Octreotide is the first choice in the control of hormone mediated symptoms. From retrospective and a few prospective studies it has been suggested that octreotide exhibits antiproliferative properties. The prospective German Sandostatin multicentre phase II trial investigated the effects of 200 micrograms octreotide thrice daily for one year on tumour growth and endocrine abnormalities in 103 patients. Octreotide treatment was continued in those patients responding to the drug until tumour progression occurred. In 28 of those with tumour progression during 200 micrograms thrice daily octreotide dose was increased to 500 micrograms thrice daily. The study sample consisted of 52 patients with computed tomography confirmed tumour progression and 13 patients with stable disease before octreotide treatment, whereas no preobservation period was available in 38 patients. Nineteen patients (36.5%) with computed tomography confirmed tumour progression experienced stabilisation of tumour growth lasting for at least three months. Median duration of stable disease was 18 months. At month 12, stable disease continued in 12 patients, declined after 24 months to nine patients, and after 36 months to five patients. Tumour regression has not been seen in this or other subgroups. In the subgroup with stable disease before octreotide, stable disease continued in 53.8% of patients over 12 months. Increase of octreotide dose to 500 micrograms thrice daily did not influence progression seen during the lower dose with the exception of one patient in whom tumour progression changed to stable disease. No association of tumour size response and patients' characteristics could be detected. The results suggest that octreotide inhibits tumour growth in patients with metastasised endocrine GEP tumours. The antiproliferative effect is, at least in some patients, longlasting. Currently, octreotide can only be recommended as an antiproliferative drug if patients with clearly progressive disease show stabilisation after treatment for three to six months.

Adenoma, Islet Cell↗