Malignant transformation of renal angiomyolipoma.

In the present paper, two cases of malignant transformation of renal angiomyolipoma without tuberous sclerosis are reported. Pathological examination revealed that, in both cases, in addition to the areas affected by typical angiomyolipoma, there were areas that contained elevated numbers of perivascular epithelioid cells with prominent nuclear pleomorphism. Immunohistochemical examination revealed that both cases were negative for keratin and epithelial membrane antigen, but were positive for the melanogenesis-related marker HMB-45.

Noninvasive recording of His-Purkinje activity in patients with complete atrioventricular block. Clinical application of an "automated discrimination circuit".

In seven patients with complete atrioventricular (AV) block, His bundle electrograms (HBEs), standard ECG recordings, bipolar esophageal ECGs and highly amplified, filtered, bipolar chest lead ECGs were simultaneously recorded. The filtered chest lead ECG was averaged to determine His-Purkinje activity (HPA). A simplified device, the "automated discrimination circuit," was used to selectively eliminate the superimposed atrial and ventricular potentials that are characteristic of complete AV block and unsuitable for signal averaging.