An excess of massive stars in the local 30 Doradus starburst.

The 30 Doradus star-forming region in the Large Magellanic Cloud is a nearby analog of large star-formation events in the distant universe. We determined the recent formation history and the initial mass function (IMF) of massive stars in 30 Doradus on the basis of spectroscopic observations of 247 stars more massive than 15 solar masses ([Formula: see text]). The main episode of massive star formation began about 8 million years (My) ago, and the star-formation rate seems to have declined in the last 1 My. The IMF is densely sampled up to 200 [Formula: see text] and contains 32 ± 12% more stars above 30 [Formula: see text] than predicted by a standard Salpeter IMF. In the mass range of 15 to 200 [Formula: see text], the IMF power-law exponent is [Formula: see text], shallower than the Salpeter value of 2.35.

Infrared diffuse interstellar bands in the Galactic Centre region.

The spectrum of any star viewed through a sufficient quantity of diffuse interstellar material reveals a number of absorption features collectively called 'diffuse interstellar bands' (DIBs). The first DIBs were reported about 90 years ago, and currently well over 500 are known. None of them has been convincingly identified with any specific element or molecule, although recent studies suggest that the DIB carriers are polyatomic molecules containing carbon. Most of the DIBs currently known are at visible and very near-infrared wavelengths, with only two previously known at wavelengths beyond one micrometre (10,000 ångströms), the longer of which is at 1.318 micrometres (ref. 6). Here we report 13 diffuse interstellar bands in the 1.5-1.8 micrometre interval on high-extinction sightlines towards stars in the Galactic Centre. We argue that they originate almost entirely in the Galactic Centre region, a considerably warmer and harsher environment than where DIBs have been observed previously. The relative strengths of these DIBs towards the Galactic Centre and the Cygnus OB2 diffuse cloud are consistent with their strengths scaling mainly with the extinction by diffuse material.

Tratamiento con linezolid oral en osteomielitis postraumáticas / Treatment of posttraumatic osteomyelitis with oral linezolid

Objetivo. Valorar la eficacia y seguridad de linezolid oral asociado a cirugía en el tratamiento de las osteomielitis postraumáticas. Material y método. Estudio prospectivo monitorizado de todos los pacientes ingresados en la unidad de infecciones óseas y articulares del hospital con osteomielitis postraumática por cocos grampositivos meticilín resistentes tratados con cirugía programada y linezolid, 600 mg cada doce horas, desde junio de 2002 hasta diciembre de 2004. Resultados. Hemos tratado con linezolid a nueve pacientes con osteomielitis postraumática. Los microorganismos aislados han sido: un Staphylococcus aureus meticilín resistente, un estafilococo coagulasa negativo meticilín resistente, siete Staphylococcus epidermidis meticilín resistentes. Dos pacientes han tenido infección asociada con Pseudomonas aeruginosa. La duración media del tratamiento ha sido de 9,5 semanas (rango 6-12). En el seguimiento realizado ocho pacientes están clínicamente curados con estabilización de la fractura y sin signos de infección. Un paciente está en situación de pseudoartrosis infectada. El linezolid ha sido tolerado de manera excelente y no ha habido necesidad de suspender la medicación por toxicidad en ningún caso. Conclusiones. En nuestra experiencia, linezolid oral asociado a cirugía puede ser una excelente opción de tratamiento en osteomielitis postraumática causada por bacterias grampositivas resistentes a meticilina que no respondan a la administración de otros antimicrobianos o que no toleren éstos

Purpose. To assess the efficacy and safety of oral linezolid associated with surgery in the treatment of posttraumatic osteomyelitis. Materials and methods. Monitored prospective study of all patients suffering from posttraumatic osteomyelitis caused by Methicillin-resistant Gram positive cocci treated with elective surgery and linezolid 600 mg every 12 hours from June 2002 to December 2004. Results. We have used linezolid to treat 9 patients with posttraumatic osteomyelitis. The microorganisms isolated were: Methicillin-resistant Staphylococcus aureus, 1; Methicillin-resistant Staphylococcus epidermidis, 7. Two patients had an associated infection caused by Pseudomonas aeruginosa. Mean duration of treatment was 9.5 weeks (range 6-12). During follow-up 8 patients were found to be clinically cured with fracture stabilization and with no sign of infection. One patient had an infected mal-union. Linezolid was excellently tolerated and in none of the cases it was necessary to discontinue administration due to toxicity. Conclusions. In our experience oral linezolid associated with surgery can be an excellent option for the treatment of posttraumatic osteomyelitis caused by Methicillin-resistant Gram positive bacteria that do not respond to other antimicrobials or if these are not well tolerated (AU)

Windows through the dusty disks surrounding the youngest low-mass protostellar objects.

The formation and evolution of young low-mass stars are characterized by important processes of mass loss and accretion occurring in the innermost regions of their placentary circumstellar disks. Because of the large obscuration of these disks at optical and infrared wavelengths in the early protostellar stages (class 0 sources), they were previously detected only at radio wavelengths using interferometric techniques. We have detected with the Infrared Space Observatory the mid-infrared (mid-IR) emission associated with the class 0 protostar VLA1 in the HH1-HH2 region located in the Orion nebula. The emission arises in three wavelength windows (at 5. 3, 6.6, and 7.5 micrometers) where the absorption due to ices and silicates has a local minimum that exposes the central part of the young protostellar system to mid-IR investigations. The mid-IR emission arises from a central source with a diameter of 4 astronomical units at an averaged temperature of approximately 700 K, deeply embedded in a dense region with a visual extinction of 80 to 100 magnitudes.

A Second Luminous Blue Variable in the Quintuplet Cluster.

H- and K-band moderate-resolution and 4 µm high-resolution spectra have been obtained for FMM 362, a bright star in the Quintuplet Cluster near the Galactic center. The spectral features in these bands closely match those of the Pistol Star, a luminous blue variable and one of the most luminous stars known. The new spectra and previously obtained photometry imply a very high luminosity for FMM 362, L>/=106 L middle dot in circle, and a temperature of 10,000-13,000 K. Based on its luminosity, temperature, photometric variability, and similarities to the Pistol Star, we conclude that FMM 362 is a luminous blue variable.

Hepatotoxicity due to lysine salt of bendazac.

BACKGROUND: The lysine salt of bendazac is a non-steroidal anti-inflammatory agent, and it is marketed exclusively for the treatment of cataracts. We report two cases of possible hepatotoxicity due to the use of bendazac lysine. METHODS: Laboratory tests, serologic tests, abdominal sonography and scan were performed to study liver disease. RESULTS: Reversible increases of the hepatic enzymes were found in both cases. Anemia was also found in one of the cases (case 1). CONCLUSIONS: Abnormal liver test results could be related to a possible liver injury attributed to the use of bendazac lysine.