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Biomedical subjects

B Lembcke

Publications and source records attributed to B Lembcke.

At least 91 records · Page 5Linked to original sources
PubMed1991

Effect of bromocriptine withdrawal in acromegaly on body composition as assessed by bioelectrical impedance analysis.

To evaluate the effect of bromocriptine withdrawal after dopaminergic long-term treatment (15.0 +/- 6.8 mg/day, mean +/- SD) in 12 acromegalic patients on body composition, bioelectrical impedance was measured before and at the end of two weeks of drug withdrawal. During withdrawal basal hGH and IGF-I increased from 2.5 +/- 1.9 micrograms/l and 2.1 +/- 0.8 kU/l to 9.1 +/- 11.7 micrograms/l and 4.9 +/- 2.2 kU/l, respectively, and the hGH secretion deteriorated significantly both after oral glucose load and in the TRH test, indicating recurrence of active acromegaly. Reactance and resistance decreased by 5 +/- 4 and 23 +/- 19 omega, respectively (p less than 0.01), whereas body weight remained constant (+0.4 +/- 2.1 kg). Bioelectrical impedance analysis indicated evident shifts in body composition, i.e. a significant reduction of body fat (-2.0 +/- 1.7 kg) and a simultaneous increase in both lean body mass (+2.4 +/- 2.2 kg) and total body water (+1.8 +/- 1.6 l). The changes in body composition were related to a combined effect of unsuppressed hypersomatotropism and the lack of bromocriptine actions other than inhibition of hGH secretion (for example stimulation of the renin-angiotensin-aldosterone system by both the recurred hypersomatotropism and the absence of dopaminergic bromocriptine effects). We conclude that bioelectrical impedance analysis is a good additional tool to assess the pathophysiological effects of bromocriptine withdrawal in long-term treated acromegalic patients.

Acromegaly↗
PubMed1991

[Sonography in Crohn disease--the conclusions of an experts' group].

Sonography is adding a new dimension to diagnosis of Crohn's disease: the analysis of the transmural and peri-intestinal manifestations of the chronic inflammation. Distortions in the structure of intestinal wall are recognizable, the impact on transport of intestinal content can be judged, penetration of inflammation into the bowel surrounding as fistula, abscess, mesenteriitis und peritonitis is safely seen. Differential diagnosis on a strictly sonographic basis is difficult. The paper represents the results of an expert meeting held at the University of Frankfurt/M.

Crohn Disease↗
PubMed1990

[Cystic polyposis of the stomach].

An X-ray contrast medium examination revealed extensive polyposis in the gastric fundus of a 66-year-old patient with intermittent heartburn. Physical examination and laboratory tests including carcinoembryonal antigen yielded no abnormal findings. Gastroduodenoscopy showed more than 100 polyps of about 5 mm diameter in the fundus and corpus of the stomach. Gastric mucosa was histologically intact. Numerous cysts lined by non-pathological epithelia were seen in the body and neck of the gastric glands. No polyps were found in the small bowel or colon. Since cystic polyposis does not tend to become malignant, no surgery was performed. Annual endoscopic controls, however, are recommended.

Aged↗
PubMed1990

Postprandial glycemic control, hormonal effects and carbohydrate malabsorption during long-term administration of the alpha-glucosidase inhibitor miglitol.

This double-blind study was performed to evaluate the relation of the glycemic and hormonal (insulin, gastric inhibitory polypeptide) responses to standardized starch and sucrose meals to signs (H2 exhalation) and subjective symptoms of carbohydrate malabsorption during administration of 100 mg BAYm 1099 (miglitol) t.i.d. over a period of 8 weeks. Two groups of 8 male healthy volunteers received either placebo or verum. Oral sucrose loading tests (50 g) with and without miglitol were performed at day -5, 1, 25 and 53 of the study, starch loading tests (50 g) with and without the inhibitor were carried out at day -2, 4, 28 and 56. Miglitol significantly flattened the glycemic responses to sucrose and starch without evidence of diminished efficacy over the 8-week period. Also the blunting effect of miglitol on serum insulin and gastric inhibitory polypeptide responses and the stimulation of breath hydrogen exhalation proving carbohydrate malabsorption with starch and sucrose remained unchanged over time. Comparing breath hydrogen exhalation, responses were more pronounced after sucrose than after the starch loading tests. Symptoms (bloating, flatulence, diarrhea, cramps) were merely noticeable with starch as the substrate, but clearly present after sucrose. These symptoms were substantially curtailed during continuous drug intake. It is concluded that - irrespective of the substrate (starch/sucrose) - there is no escape of the desired effects of alpha-glucosidase inhibition by miglitol over 8 weeks, but symptoms of gaseousness due to carbohydrate malabsorption may undergo habituation.

1-Deoxynojirimycin↗
PubMed1990

Clinical evaluation of a 25 g D-xylose hydrogen (H2) breath test.

Breath hydrogen (H2) exhalation after xylose administration reflects the malabsorbed portion of the pentose and thus might facilitate the application of the D-xylose test. Therefore, as a complementary parameter, breath H2-exhalation in response to 25 g D-xylose was assessed in control subjects, in patients with coeliac disease, with chronic pancreatitis and with the irritable bowel syndrome. Patients with coeliac disease showed significantly higher breath H2 concentrations than the controls. Specificity and the positive predictive value of peak H2-increments greater than 56 ppm (i.e. greater than mean + 2 SD of controls) were 100%, but sensitivity was only 40%. In all patients with a positive H2 breath test, urinary D-xylose excretion and serum D-xylose increments were also abnormal. Apart from great overlap between controls and patients with coeliac disease, the failure to produce H2 in response to D-xylose in 12% of the 57 investigated subjects was the major factor limiting diagnostic efficiency of the test. Non H2 production could be shown to reflect a specific metabolic disability of the colonic flora and did not prove complete absorption of the substrate. It is concluded, that the 25 g D-xylose H2 breath test is of no clinical relevance for the diagnosis of celiac sprue but exaggerated breath H2 increases (greater than 56 ppm) with normal urinary and D-xylose tests were indicative for the irritable bowel syndrome in 5 out of 10 patients. The diagnostic impact of this constellation thus merits further investigation.

Adult↗
PubMed1989

New and versatile method for the determination of faecal bile acids by thin-layer chromatography with direct scanning fluorimetry.

A sensitive, versatile and precise method for quantitative analysis of individual faecal bile acids in humans by thin-layer chromatography with direct scanning fluorimetry is described. The method enables convenient quantitative measurements of faecal bile acids in larger series of samples for routine applications in gastroenterology. The overall coefficient of variation (including stool preparation and extraction) for the five predominant bile acids of human stool specimens (cholic acid, chenodeoxycholic acid, deoxycholic acid, lithocholic acid and ursodeoxycholic acid) was 3.4-4.9%. Recoveries of free bile acids added to the faeces ranged from 91% to 106%. An excellent and linear correlation between this method and fused-silica column gas chromatography with temperature programming was established (r = 0.91-0.99). In clinical practice this thin-layer chromatographic method constitutes a reliable, simple and time-saving alternative to gas chromatography.

Bile Acids and Salts↗
PubMed1989

Is the assay of disaccharidase activity in small bowel mucosal biopsy relevant for clinical gastroenterologists?

In a retrospective study, jejunal mucosal disaccharidase and alkaline phosphatase activities have been investigated in 40 controls and patients with proven celiac sprue (n = 26), lactase deficiency (n = 26), osteoporosis or osteomalacia (n = 16), chronic pancreatitis (n = 12), giardiasis (n = 7), or Crohn's disease (n = 7). Apart from a nonselective reduction of mucosal enzyme activities in the sprue syndrome and a selective reduction of lactase activity in the patients with primary lactase deficiency, assays of mucosal disaccharidases revealed only inconstant or slight deviations from the control group and were not of diagnostic significance for any of the above-mentioned disorders. Isolated forms of enzyme deficiencies other than lactase deficiency, such as sucrase-isomaltase or trehalase deficiency were not present among 168 investigations carried out from 1972-1982. It is concluded that assay of small intestinal disaccharidase or alkaline phosphatase activities does not expand the diagnostic impact of morphological examination of small bowel biopsy specimens and modern noninvasive methods for the detection of carbohydrate malabsorption. Thus, the method does not appear a necessary or relevant investigation in routine clinical practice.

Adolescent↗
PubMed1989

[Serum beta-carotene: a simple static laboratory parameter for the diagnosis of steatorrhea].

The value of serum beta-carotene concentration as an indicator of steatorrhoea was investigated in 50 patients with steatorrhoea (fecal fat greater than 7 g/day), 53 controls, and 22 patients with gastrointestinal disease without steatorrhoea. In the control group, beta-carotene concentrations were normally distributed when plotted logarithmically. The mean value was 131 micrograms/dl. The lower limit of normal, based on a 2-SD confidence interval, was 47 micrograms/dl. beta-Carotene concentrations and fecal fat excretion were correlated in a reciprocal, hyperbolic function (r = -0.66). Twenty-nine of the 50 patients with steatorrhoea had beta-carotene concentrations less than 47 micrograms/dl (sensitivity 58%; specificity 93%). Referring to an additional cut-off point of 100 micrograms/dl, beta-carotene concentration had a sensitivity of 88%. These data show that low plasma beta-carotene concentrations (less than 47 micrograms/dl) can be regarded a specific and useful indicator of steatorrhoea and thus obviate fecal fat analysis. Values greater than 47 micrograms/dl, however do not exclude steatorrhoea. Based on a two-step interpretation beta-carotene is thus both a useful screening test for steatorrhoea (with a cut-off point of 100 micrograms/dl) and, more important, a valid, simple, and clinically practical alternative for fecal fat analysis (if values are less than 47 micrograms/dl).

Carotenoids↗
PubMed1989

[Causes and clinical diagnosis of chologenic diarrhea].

Among the numerous differential diagnoses of chronic diarrhea, chologenic diarrhea is rarely taken into account. However, diseases or postoperative syndromes leading to bile acid malabsorption and thus resulting in chologenic diarrhea such as Crohn's disease or ileal resections have increased considerably. Further, malabsorption of bile acids might be incriminated in the pathogenesis or sequels of other digestive diseases (e.g. irritable bowel syndrome or chronic pancreatitis) and also can be the only characteristic in the rare "idiopathic" bile acid malabsorption. Etiologies, pathophysiology and the clinical sequels of impaired bile acid absorption have been elucidated in recent years, but in clinical medicine several questions remained unresolved since valid and generally acceptable analytical methods for the detection of bile acid malabsorption have not been developed until recently. In this field, radioisotope methods have considerably expanded our diagnostic facilities.

Bile Acids and Salts↗