In acute embolic renal artery occlusion, thrombolytic therapy does not restore renal function and is therefore not indicated once the ischemic tolerance of the kidney (approximately 90 minutes) has been exceeded.

Medullary cystic kidney disease (MCD) is characterized by multiple renal cysts at the corticomedullary boundary area, by autosomal dominant inheritance, and by onset of chronic renal failure in the third decade of life. We report on a family with three affected individuals of both sexes in two generations presenting with end-stage renal failure at age 22-31 years. Primarily diagnoses considered included unclassified hereditary nephropathy and autosomal dominant polycystic kidney disease. Careful evaluation of all findings, initiated after investigation of renal morphology with CT, revealed features characteristic for MCD and led to the final diagnosis of MCD. We conclude that MCD is an important differential diagnosis for polycystic kidney disease in young adults with end-stage renal failure. Establishing the correct diagnosis has considerable impact for genetic counselling.

Computer-assisted laser-fluorescence videography is a feasible, reliable, and valid experimental method for the detection of mesenteric blood supply and intestinal microcirculation. Clinical application is conceivable in mesenteric ischaemia and infarction as well as the operative transposition of intestine. As limiting values to identify the irreversible necrosis are not yet defined, further studies have to analyse the clinical impact more precisely.

Between January 1974 and November 1991 33 children received a permanent single- or dual-chamber pacing system, mainly because of postoperative high-degree AV block. The children were followed up retrospectively for pacemaker- and lead-related complications, and for differences between epi- and endocardial stimulation. The overall rate of lead related complications was 35% and did not differ significantly between the epi- and endocardially paced groups, although it tended to be somewhat higher in the epicardially paced children, mainly due to a higher rate of exit blocks in the latter. The epicardially stimulated patients exhibited a significantly higher rate of pacemaker-related complications, which was primarily accounted for by a higher frequency of battery depletions in the epicardial systems. The most impressive differences between both groups, however, was seen with respect to subacute and chronic energy consumption. Chronic energy drain in the epicardially paced patients amounted to almost the sixfold of that seen in the endocardially stimulated children. This resulted in a significantly shorter cumulative pacemaker survival in the epicardial group. Therefore, it is concluded that, whenever possible, the transvenous approach be used in children and small infants too. However, as a rule, in the latter transvenous dualchamber pacing is usually not feasible. In these cases rate-adaptive single-chamber pacing has evolved as a reasonable alternative for improving hemodynamics as well as quality of life. In epicardial pacing the use of pulse generators allowing bidirectional telemetry is advisable. In this way monitoring of lead impedance and battery status can be performed noninvasively, thus permitting individualization of pulse widths and amplitude setting, which is important with respect to energy conservation.

A method is described for the dissociation of guinea pig lung and mesentery into their component cells. The method comprises incubation of the tissues with the enzyme pronase in Ca++- and Mg++-free saline followed by mechanical dispersion and yields on average 3-8% free mast cells. These cells are morphologically intact and viable. They retain an active sensitization or can be passively sensitized. The levels of cAMP and cGMP in the whole cell suspension respond to catecholamine, histamine or cholinergic stimulation in a way similar to that observed in the corresponding undispersed tissue. Although the separation of guinea pig mast cells from other cells proved to be more difficult than the purification of rat mast cells, an inrichment of greater than 50% has been achieved. The mast cells isolated by this method proliferate in vitro and have been cultured successfully for several months.

No abstract

The divalent cation ionophore A23187 was found to produce a dose-dependent release of histamine from isolated mesenteric mast cells of the guinea pig. The process showed a specific requirement for calcium ions and was blocked by inhibitors of glycolysis. The effect of cAMP, theophylline, sympathomimetic amines and DSCG on the histamine release induced by the ionophore or by the antigen-antibody reaction was compared. In both cases, the release was inhibited by Bu2cAMP and by theophylline but higher concentrations were required with the ionophore. Adrenaline, isoprenaline and DSCG were effective only in the anaphylactic system. These results are compared with those previously reported for human leucocytes and rat peritoneal mast cells in which the release produced by the ionophore was found not to be inhibited by cAMP and its analogues. On the basis of these findings, the possible role of cAMP in the modulation of histamine release is discussed.

In a prospective study we examined the diagnostic ranking of CT and MR in 52 immunocompromised patients with nodular pulmonary lesions and clinical suspicion of invasive pulmonary aspergillosis (IPA). For early diagnosis of IPA (clinical symptoms having existed for less than 10 days) the CT halo sign proved highly sensitive and specific. MRT showed at this time a comparatively high sensitivity but only low specificity that could not be improved upon after Gd-DTPA. At a later stage of the aspergillosis infection (clinical symptoms manifested for more than 10 days) MR identified aspergillus-specific lesions with on-target characteristics (marked enhancement of margins after Gd-DTPA) or the so-called "reverse" target phenomenon (T2-weighted sequences). Such lesions were never seen in the early stage of the disease in patients with nodular pulmonary lesions of different aetiology (pseudomonal or staphylococcal pneumonia).