Can ECG changes predict the long-term outcome in patients admitted to hospital for suspected acute myocardial infarction?

SETTING: The activity of KRM 1648 (KRM), a new benzoxazinorifamycin, and rifabutin (RBT), alone or in combination with clarithromycin (CLA), was evaluated against Mycobacterium avium complex (MAC) that multiplied in human alveolar macrophages (AM). DESIGN: AM were recovered by bronchoalveolar lavage, incubated in RPMI 1640 medium with 10% human AB serum, infected with four strains of MAC (of non-acquired immune deficiency syndrome [AIDS] origin), and then treated with each drug alone or in combination. After incubation for 7 days, colony forming units in each well were counted on 7H10 agar. RESULTS: Although concentrations between 0.2 microgram/ml and 20 micrograms/ml of both rifamycins showed clear dose-dependent activities against all MAC strains tested, only 20 micrograms/ml of each drug had modest bactericidal effect. In combination with 2.0 micrograms/ml of CLA, however, 0.2 microgram/ml of both drugs caused a bactericidal response against two of the four MAC strains examined. CONCLUSION: According to this human alveolar macrophage model of MAC infection, KRM and RBT in combination with CLA was found to be a promising candidate against human pulmonary MAC infection, and deserves clinical evaluation.     

Axonal damage revealed by accumulation of beta-APP in HIV-positive individuals without AIDS

The presence of neuropsychological disturbances in HIV-positive, pre-symptomatic individuals is a controversial issue. Neuroimaging studies have not shown brain atrophy or hyperintensity in the white matter, whereas proton magnetic resonance spectroscopy has revealed some abnormality of cerebral biochemistry. Using an antibody to beta-amyloid precursor protein (beta-APP), we previously demonstrated frequent and widespread axonal changes in the brains of AIDS patients. In this study, we extended the use of beta-APP to asymptomatic patients in order to establish a possible morphological correlation with neuropsychological disorders. Brain samples from 29 patients were examined. Results showed bundles of beta-APP-positive axons in 8/29 cases (27%). The changes, seen in both superficial and deep white matter, were either focal or diffuse, could not be visualized by silver or ubiquitin stains, and did not coexist with any change in distribution or morphology of astrocytes and microglial cells. We conclude that in HIV-positive asymptomatic individuals, axonal changes: (a) may be related to the state of immune activation with consequent presence of toxic substances, including cytokines, observed in these patients; (b) may represent mild changes that could undergo repair, unless other pathological events, such as the supervening of the AIDS stage and the specific encephalitis, make them permanent.     

Lymphangioma of the right kidney in an infant boy

A 9-month-old boy with a primary cystic lymphangioma of the right kidney is reported. The clinical and radiological features favored a malignant tumor. Histology revealed the lesion to be a lymphangioma; the diagnosis was confirmed by immunohistochemistry and chemical analysis of the intracystic fluid. Lymphangiomas of the kidney are rare in adults; they are even rarer in infants and children. Nevertheless, renal lymphangiomas should be considered in the differential diagnosis of multicystic, unilateral renal masses, independent of the age of the patient.