Fast-moving stars around an intermediate-mass black hole in ω Centauri.

Black holes have been found over a wide range of masses, from stellar remnants with masses of 5-150 solar masses (M), to those found at the centres of galaxies with M > 10M. However, only a few debated candidate black holes exist between 150M and 10M. Determining the population of these intermediate-mass black holes is an important step towards understanding supermassive black hole formation in the early universe.

NGC1818 unveils the origin of the extended main-sequence turn-off in young Magellanic Clouds clusters.

The origin of young star clusters represents a major challenge for modern stellar astrophysics. While stellar rotation partially explains the colour spread observed along main-sequence turn-offs, i.e.

Rapidly rotating second-generation progenitors for the 'blue hook' stars of ω Centauri.

Horizontal branch stars belong to an advanced stage in the evolution of the oldest stellar galactic population, occurring either as field halo stars or grouped in globular clusters. The discovery of multiple populations in clusters that were previously believed to have single populations gave rise to the currently accepted theory that the hottest horizontal branch members (the 'blue hook' stars, which had late helium-core flash ignition, followed by deep mixing) are the progeny of a helium-rich 'second generation' of stars. It is not known why such a supposedly rare event (a late flash followed by mixing) is so common that the blue hook of ω Centauri contains approximately 30 per cent of the horizontal branch stars in the cluster, or why the blue hook luminosity range in this massive cluster cannot be reproduced by models.

[Hypoparathyroid risk after total thyroidectomy].

From January 1970 to December 1999, 881 patients with thyroid pathology underwent surgery consisting in 551 subtotal thyroidectomies and 330 total thyroidectomies. Permanent hypocalcaemia was present in 32 patients (3.6%).

[Tubulo-villous rectal tumours. Results of surgical resection in relation to histotype (30 years' experience)].

Adenomas of the rectum are frequently found during endoscopic examination. We report on our 30 years of experience with the treatment of tubulo-villous adenomas based on histotype. Between 1971 and 2001, 104 villous tumours of the rectum were treated surgically.

[Surgical treatment of rectal prolapse with transanal resection according to Altemeier. Experience and results].

In recent years the number of patients with partial or total rectal prolapse has increased. Numerous techniques and surgical approaches have been described for its treatment. In this study we examine the main ones and stress the advantages of the transanal-perineal resection technique according to Altemeier and modified by Prasad, which we have used to treat the condition in the last 15 years.

[Surgical treatment of anal stenosis following hemorrhoid surgery. Results of 150 combined mucosal advancement and internal sphincterotomy].

The aim of the study was to evaluate the efficacy of anoplasty by mucosal advancement combined with internal sphincterotomy for the treatment of iatrogenic anal stenosis. From January 1990 to December 2000, 149 patients with post-haemorrhoidectomy anal strictures underwent internal sphincterotomy and mucosal advancement flap anoplasty. Seventy-one percent of patients were operated on under local anaesthesia by perineal block according to Marti.

[Surgical treatment of acute respiratory failure caused by mediastinal goiter. Clinical experience and results].

In the regions where goitre is endemic, onset of the disease with acute respiratory insufficiency caused by thyroid compression is an uncommon situation requiring a rapid diagnosis and urgent surgical treatment. From January 1997 to December 2000 we observed 81 patients with thyroid pathologies, (69 males and 12 females; mean age 64 years). We found colloid-cystic goitre in 39 cases, adenomatous goitre in 26, carcinoma in 12, Hürthle's cell tumours in 3 and inflammatory disease in 1.