Bladder cancer: staging with CT and MR imaging

Magnetic resonance (MR) imaging and computed tomography (CT) were compared in 30 patients with histologically proved bladder cancer. MR imaging was accurate in depicting the presence or absence of extravesical spread in 22 patients (accuracy, 73%; sensitivity, 82%; specificity, 62%), and CT was accurate in 24 patients (accuracy, 80%; sensitivity, 94%; specificity, 62%). The MR examinations of two patients were of undiagnostic quality and therefore considered to be technical failures. Each technique resulted in five false-positive and one false-negative examination for the diagnosis of extravesical tumor spread. In 28 patients the integrity of the bladder wall was assessed with MR imaging. In 22 patients the bladder wall was disrupted, and 18 of these patients had deep muscle invasion. In six patients the bladder wall was intact, and none of these patients had evidence of deep muscle invasion at pathologic examination. In this study MR imaging was slightly inferior to CT in the delineation of invasive tumors beyond the bladder wall. However, if one excludes from analysis the two patients with undiagnostic studies, there is no significant difference in accuracy between the two techniques.     

Evaluation of three psychologic interventions to reduce anxiety during MR imaging

The authors compared the effectiveness of three anxiety-reducing interventions for patients undergoing magnetic resonance imaging. Each of 50 subjects was randomly assigned to one of the interventions. Intervention 1 involved provision of information about the imager and nature of the examination. Intervention 2 included information and counseling. Intervention 3 included information and a 12-minute relaxation exercise. Anxiety levels were measured by means of a 20-item questionnaire before and after imaging. The latter provided a retrospective report of anxiety experienced during imaging. Patients in intervention group 3 showed significantly less increase in anxiety compared with those in groups 1 and 2. Overall, only patients who participated in intervention 1 showed a significant increase in anxiety during imaging. When anxiety levels experienced before and during the examination were compared, with the focus on each questionnaire item for each group, those in group 1 showed a significant increase in anxiety on eight of 20 items; those in group 2, three items; and those in group 3, none. Psychologic preparation that includes relaxation strategies is more effective than provision of information alone.     

Role of asynchronous activation of the ventricular fibres by an ectopic pacemaker in the accidents, especially fibrillation, caused by Ic antiarrhythmic drugs

Class Ic antiarrhythmic drugs, which are known to slow down conduction in the ventricular muscle, are likely to impair synchrony in activity of the ventricular fibres. Asynchronous activation was first investigated between an ischaemic and a normal area by the simultaneous recording in anaesthetized, open-chest pigs of two left ventricular monophasic action potentials (MAPs) under ventricular pacing at a high rate of 180 beats.min-1. Asynchronous activation was then investigated in the intact myocardium according to the distance separating the recording from the pacing electrode. Furthermore, mechanical effects of left ventricular systole were observed by recording dP/dt(max) and mean arterial blood pressure during the pacing periods. Ischaemia was produced by transient complete occlusion of the left anterior descending coronary artery near its origin; as a result, activation time reached 85 ms in the ischaemic area under flecainide administered iv in a 2.5 mg.kg-1 dose instead of approximately 60 ms in the normal area for fibres equi-distant from the pacing electrode. Similar delays in activation were observed in the intact myocardium, depending on whether the explored region was close to or far from the pacing electrode. In the latter case, the difference in activation time may become markedly greater if the distance or the dose of flecainide are increased. This difference, which possibly exceeds one-third of the MAP duration (practically unchanged by flecainide), may account for the occurrence of fibrillation or the sudden loss of systole mechanical efficacy.     

Diffuse primary cutaneous amyloidosis

A case of extensive primary cutaneous amyloidosis exhibiting both macular and lichenoid lesions is reported. Lesions were arranged in a distinctive linear pattern covering much of the trunk and limbs, in places following Blaschko's lines. The coexistence of macular and lichenoid lesions suggests that this is an unusual variant of biphasic cutaneous amyloidosis.     

圆二色谱在天然产物——二萜双向酯和娃儿藤碱的结构分析中的应用

本文报道了四个二萜双内酯和五个娃儿藤碱的圆二色谱、扇形图和反八区律,其中6和8为新化合物。文中提出的反八区律图首先应用于二萜双内酯的构型测定,我们应用有关的规则,所预测的这些化合物的Cotton效应和实测结果一致,从而指定了它们的绝对构型。