The prevalence of avascular necrosis in sickle cell anemia: correlation with alpha-thalassemia

The purpose of the present study was to investigate the effect of alpha-thalassemia on the prevalence of avascular necrosis in 52 adult patients with sickle cell anemia. alpha-Globin genotypes were determined by restriction endonuclease mapping of genomic DNA extracted from peripheral blood leukocytes. Radiographs of humeral and femoral heads were interpreted by two radiologists who were not aware of the clinical picture and the genotype of the patients in the study. We present data showing that there is a significant positive correlation between alpha-gene deletion and the prevalence and extent of avascular necrosis in our patient population.     

Intrauterine PGF2 alpha infusion for termination of pregnancies with second-trimester rupture of membranes.

Intrauterine prostaglandin (PG) F2 alpha infusion and intravenous (IV) oxytocin infusion were compared to evaluate the effectiveness of the two methods for termination of pregnancies with second-trimester rupture of membranes. Twenty-two women with this complication were randomly allocated to receive either 20 mg PGF2 alpha, diluted in 500 mL of NaCl 0.9% and administered through a Foley catheter inserted through the cervix, or IV oxytocin infusion in increasing doses. All subjects in the PGF2 alpha group aborted after the first administration. Repeat infusion was necessary in three oxytocin-treated subjects. The mean (+/- SD) induction-abortion interval was significantly shorter in those receiving PGF2 alpha (6.7 +/- 1.2 hours) than in those receiving oxytocin (8.8 +/- 2.7 hours). Minor side effects, such as nausea and vomiting, were observed in three women during PGF2 alpha infusion and were treated symptomatically and by temporary interruption of the infusion. Uterine hypertonus, observed in one subject in each group, was treated by temporary cessation of the infusion. We conclude that intrauterine PGF2 alpha infusion seems more effective than IV oxytocin for termination of pregnancies with second-trimester rupture of membranes.     

A correlation between receptive field properties and morphological structures in the pretectum of the cat

Retinal terminals in the pretectum were labelled by anterograde axonal transport of horseradish peroxidase (HRP) after injecting the enzyme into one eye. Pretectal neurons were retrogradely labelled by HRP-injections into the dorsal cap of the inferior olive. Electrophysiological recordings were performed in the same animal. This procedure showed that direction-selective neurons in the nucleus of the optic tract (NOT) projecting to the dorsal cap of the inferior olive lie dorsal and lateral to the retinal terminal clusters. Direction-unselective neurons sensitive to high stimulus velocities (jerk-neurons) were localized within the areas of retinal terminal clusters. Both jerk-neurons and retinal terminal clusters never overlapped with retrogradely labelled neurons. Latency measurements to stimulation of the optic chiasm (OX) confirmed a monosynaptic W-cell projection to the direction-selective NOT cells and indicated a predominantly monosynaptic Y-cell projection to the jerk-neurons.     

Gangrenous cystitis

Gangrenous cystitis is an extremely rare condition. During the last 70 years, only 30 cases have been reported in the literature. We report a case of gangrenous cystitis in a 70-year-old woman presented with symptoms of acute abdomen. Main causative factor was overdistension of the bladder due to catheter obstruction. She underwent debridement and drainage of the cystic remnant. The pathogenesis, diagnosis, and management of gangrenous cystitis are discussed.     

Environmental exposure to Toxocara as a possible risk factor for asthma: a clinic-based case-control study.

The zoonotic ascarid Toxocara has been suggested as a possible etiologic agent of asthma. We conducted a clinic-based case-control study to examine whether the zoonotic infection acquired by ingesting Toxocara eggs is associated with asthma in children. Blood samples were collected from children aged 2-15 years, 95 of whom had asthma and 229 of whom did not have asthma. Risk factors for asthma and Toxocara infection were assessed by a questionnaire given to each child's parent or legal guardian. Blood samples were tested for the presence of Toxocara antibodies, using an enzyme-linked immunosorbent assay. No significant association was found between Toxocara infection and asthma. Significant associations were found between asthma and risk factors and between Toxocara infection and risk factors. High prevalence of Toxocara infection was noted among Hispanic children of Puerto Rican descent.