We investigated the pharmacokinetics of rifampicin and its major metabolites, 25-desacetylrifampicin and 3-formylrifampicin, in two groups of six patients with active pulmonary tuberculosis, who received either multiple oral or intravenous rifampicin therapy in combination with intravenous isoniazid and ethambutol. Serum concentrations of rifampicin were each determined after a single oral and intravenous test dose of 600 mg rifampicin at the beginning and after 1 and 3 weeks of tuberculostatic treatment. Analysis of rifampicin and its metabolites was performed by high-pressure liquid chromatography. It was found that, due to autoinduction of its metabolizing hepatic enzymes, the systemic clearance of rifampicin increased from 5.69 to 9.03 l/h after 3 weeks of multiple dosing. The volume of distribution of the drug was constant over the period of this study. The bioavailability of the active, orally administered rifampicin decreased from 93% after the first single oral dose to 68% after 3 weeks of oral and intravenous rifampicin therapy. Relating to the increase in systemic (hepatic) clearance, a bioavailability no lower than 90% can be predicted. The reduction to 68% indicates that, in addition to an increase of hepatic metabolism, an induction of a prehepatic "first-pass" effect resulted from multiple rifampicin doses. Our study of rifampicin metabolites confirm that prehepatic metabolism was induced, since a higher metabolic ratio resulted after the oral doses than after the intravenous rifampicin test doses. A preabsorptive process can therefore be excluded as a cause of reduced bioavailability.

Examination of 105 duodeno-pancreatectomy specimens showed that 75% of the cases of chronic pancreatitis (n = 74) manifested diffuse hyperplasia of Brunner's glands. In pancreatitis involving part of the pancreas in the presence of ducts of the embryonic type (n = 6), in segmental pancreatitis (n = 16), and in pancreatic cancer (n = 23), no significant difference in the thickness of the layer of Brunner's glands was found as compared with normal specimens. There was no statistically significant correlation between the degree of hyperplasia of Brunner's glands and the degree of scarring of the exocrine pancreatic parenchyma. Nor was there any correlation between existence and extent of scarring of the duodenal wall, inflammatory infiltration of the duodenal mucosa, duration of disease, consumption of alcohol and history of gall stones and ulcers in patients with and without hyperplasia of Brunner's glands. Diffuse hyperplasia of the duodenal glands is probably an adaptive reaction to the exocrine insufficiency of the pancreas or the changes in gastric function (hyperacidity, accelerated emptying of the stomach) caused by chronic pancreatitis. A fact which supports this statement is that the inhibitor hormone urogastrone--an inhibitor of gastric acid secretion--is formed in Brunner's glands. The question is also discussed whether chronic pancreatitis and hyperplasia of Brunner's glands might not also develop simultaneously in the presence of disturbances of the gastrointestinal hormones, themselves either primary or due to alcohol consumption.

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Magnetic resonance-guided wire localizations of suspicious breast lesions using an open high-field MR system are a clinically safe and feasible method even in small target lesions and anatomical regions that are usually considered difficult to access.

PVE with the AVP-II is a feasible and effective method. The AVP-II can dilate within 4 weeks up to its nominal diameter dependent on the grade of oversizing. Dilatation of the diameter is associated with a shortening in length.