Tarantula toxins interact with voltage sensors within lipid membranes.

Voltage-activated ion channels are essential for electrical signaling, yet the mechanism of voltage sensing remains under intense investigation. The voltage-sensor paddle is a crucial structural motif in voltage-activated potassium (K(v)) channels that has been proposed to move at the protein-lipid interface in response to changes in membrane voltage. Here we explore whether tarantula toxins like hanatoxin and SGTx1 inhibit K(v) channels by interacting with paddle motifs within the membrane.

Generation of islet-like hormone-producing cells in vitro from adult human pancreas.

Transplantation of pancreatic islets can provide long-lasting insulin independence for diabetic patients, but the current islet supply is limited. Here we describe a new in vitro system that utilizes adult human pancreatic islet-enriched fractions to generate hormone-producing cells over 3-4 weeks of culture. By labeling proliferating cells with a retrovirus-expressing green fluorescent protein, we show that in this system hormone-producing cells are generated de novo.

[Aortic valve stenosis in children. Surgical valvuloplasty long-term results].

From 1960 through 1992, 67 children with congenital aortic stenosis aged 6-228 months (M 105.7 +/- 52) were submitted to aortic valvuloplasty at our institution. There was no hospital mortality.

[Ebstein's anomaly: valvular replacement in pediatric patients].

The surgical treatment of Ebstein's anomaly is still controversial. Therefore we have retrospectively studied the results of tricuspid valve replacement (TVR) performed for this anomaly at Sainte Justine Hospital. From October 1977 to December 1997, 9 patients with Ebstein's anomaly, aged from 31 to 248 months (mean 176 +/- 66), have undergone TVR.

Long-term results of surgical valvuloplasty for congenital valvar aortic stenosis in children.

Background: To question the validity of surgical aortic valvuloplasty for congenital aortic valve stenosis, a retrospective study was undertaken to determine the long-term survival, the incidence of valve restenosis or insufficiency, and the freedom of reoperation or valve replacement.

Methods: From January 1960 through 1992, 67 consecutive children diagnosed with congenital aortic valve stenosis underwent an open aortic valvuloplasty at our institution. Ages at operation ranged from 6 to 228 months (mean 105.