Osteolytic lesions and bacillary angiomatosis in HIV infection: radiologic differentiation from AIDS-related Kaposi sarcoma.

Bacillary angiomatosis is a newly recognized multisystem bacterial infectious disease seen in the setting of human immunodeficiency virus (HIV) infection. The disease is marked by cutaneous vascular lesions that contain a bacterium similar to the cat scratch disease bacillus. Antibiotic therapy leads to the resolution of both cutaneous and systemic manifestations. Of 17 HIV-infected patients with cutaneous lesions of bacillary angiomatosis, six (35%) had symptomatic osteolytic bone lesions that improved following antibiotic therapy. The authors describe the appearance of the bone lesions on radiographs, computed tomographic (CT) scans, magnetic resonance (MR) images, and radionuclide studies. Osteolytic lesions are a relatively common feature of bacillary angiomatosis in patients with HIV infection. The presence of bone lesions aids in differentiation of bacillary angiomatosis from acquired immunodeficiency syndrome-related Kaposi sarcoma, which has similar cutaneous abnormalities but no associated bone lesions.

Respiratory and hydrostatic functions of the intestine of the catfishes Hoplosternum thoracatum and Brochis splendens (Callichthyidae).

1. The air-breathing behaviour of Hoplosternum thoracatum and Brochis splendens has been studied and their strategy of coordinating the respiratory and hydrostatic functions of the accessory respiratory organ has been examined. 2. H. thoracatum and B. splendens are continuous but not obligate air-breathers and individuals of the former breathe air in synchrony with each other. 3. Frequency of air-breathing increased with increased activity in H. thoracatum. 4. Aquatic respiration (Vo2) in H. thoracatum decreased in hypoxic water but aerial Vo2 maintained a fairly constant total Vo2 independent of aquatic O2. Total Vo2 is higher when fish breathe both air and water but aerial Vo2 did not exceed 75% of total Vo2. 5. The accessory respiratory organ provides about 75% of the lift required to attain neutral buoyancy whereas the swimbladder provides less than 5%. The mean decreases in volume of the accessory respiratory organ in the period between breaths of B. splendens and H. thoracatum were 13.2 and 7.8% respectively. 6. With a gas phase of O2, B. splendens maintained a similar frequency of air breathing and showed a slightly greater reduction in buoyancy between air breaths when compared to breathing air. With a gas phase of N2, air breathing was less frequent and decreases in buoyancy between air breaths were much less than when breathing air. 7. The respiratory and hydrostatic functions of the accessory respiratory organ are compatible. Buoyancy is maintained by frequent air breaths taken in part in response to a decrease in volume of the accessory respiratory organ. This reservoir of O2 could increase metabolic scope during bursts of activity.