Hemodynamic assessment of transluminal angioplasty for lower extremity ischemia

Seventy-two patients underwent hemodynamic testing before and after treatment for occlusive disease of their lower extremities. Percutaneous transluminal angioplasty (PTA) was used to treat lesions in 26 iliac segments and produced 23 initially improved ankle or upper thigh indices, two hemodynamic failures, and one technical failure; PTA for 54 femoropopliteal lesions produced initial hemodynamic improvement in 41 cases, three hemodynamic failures, and ten technical failures. Hemodynamic follow-up of the iliac segments showed improvement in 25 (92%) as measured by the systolic pressure index of the ankle; follow-up of the femoropopliteal segments showed continued patency of 41 (65.9%). The authors analyze these hemodynamic data.     

Small-bowel malabsorption and gastrointestinal malignancy

In addition to lymphoma, there is an increased incidence of gastrointestinal carcinoma in patients with malabsorption due to celiac disease. This is frequently manifested by a loss of response to gluten withdrawal. Four such cases are described: one patient had lymphoma and the other three had cancer of the esophagus, jejunum, and pancreas, respectively. The literature indicates that carcinoma of the esophagus and small bowel is particularly common in patients with celiac disease. These findings suggest that celiac disease should be considered a premalignant condition and that such patients should undergo a regular radiographic survey to detect early cancer.     

Major complications following endovascular surgery of descending thoracic aorta

We evaluated the impact of major complications on clinical outcome in a series of patients undergoing endovascular repair (EVAR) of descending thoracic aorta. From March 2001 to June 2005, 51 patients underwent EVAR for descending aortic diseases. Thirty-five were treated in emergency (60.7%) and 41 (80.4%) were in III-IV ASA class. There were no deaths, surgical conversion or paraplegia. A neurologic complication occurred in one patient (1.9%). Eleven major systemic complications occurred in 5 patients. One patient showed a primary type I endoleak at discharge, resolved spontaneously after 9 months. Three (5.9%) vascular injuries occurred during the endovascular procedure, requiring an emergency rescue iliac-femoral artery bypass. At follow-up (29+/-14 months), there was an overall mortality rate of 5.1% (3/51); 2 deaths (3.9%) were procedure related. Two secondary EVARs (3.9%) were successfully performed, one for a late type I endoleak six months after EVAR in a traumatic patient, and a second for a late rupture distally to the stent-graft implanted 36 months before in an acute type-B dissected patient. EVAR for descending aortic diseases is associated with decreased mortality and complications, however, long-term follow-up and additional studies are mandatory to detect late failure and to confirm clinical safety of this procedure.     

Notch promotes dynamin-dependent endocytosis of nephrin

Notch signaling in podocytes causes proteinuria and glomerulosclerosis in humans and rodents, but the underlying mechanism remains unknown. Here, we analyzed morphologic, molecular, and cellular events before the onset of proteinuria in newborn transgenic mice that express activated Notch in podocytes. Immunohistochemistry revealed a loss of the slit diaphragm protein nephrin exclusively in podocytes expressing activated Notch. Podocyte-specific deletion of Rbpj, which is essential for canonical Notch signaling, prevented this loss of nephrin. Overexpression of activated Notch decreased cell surface nephrin and increased cytoplasmic nephrin in transfected HEK293T cells; pharmacologic inhibition of dynamin, but not depletion of cholesterol, blocked these effects on nephrin, suggesting that Notch promotes dynamin-dependent, raft-independent endocytosis of nephrin. Supporting an association between Notch signaling and nephrin trafficking, electron microscopy revealed shortened podocyte foot processes and fewer slit diaphragms among the transgenic mice compared with controls. These data suggest that Notch signaling induces endocytosis of nephrin, thereby triggering the onset of proteinuria.