Administered radiopharmaceutical doses in children: a survey of 13 pediatric hospitals in North America.

Universally applied standards for administering radiopharmaceutical doses in children do not presently exist. Hence, pediatric radiopharmaceutical dosimetry varies considerably from institution to institution and is generally based on the recommended adult dose adjusted for body mass. METHODS: We surveyed 13 pediatric hospitals in North America to obtain objective data on dosimetry practices for 16 pediatric nuclear medicine examinations, including the minimum total radiopharmaceutical administered dose per examination, the total administered dose based on body mass, and maximum total doses in children. RESULTS: The reported administered doses of radiopharmaceuticals to children vary over a relatively large range, especially with respect to minimum total administered doses. CONCLUSION: This survey has identified a broad range of administered doses directly leading to variability in radiation-absorbed doses to patients. The nuclear medicine community should develop pediatric standards for radiopharmaceutical administered doses and reduce radiation exposure in children, such as through the use of modern software reconstruction techniques.     

Developmental regulation of annexin II (Lipocortin 2) in human brain and expression in high grade glioma.

In experiments to identify molecules that might be important in the pathogenesis of glioblastoma multiforme, the most common malignant brain tumor, we found that annexin II (Lipocortin 2, p36), a likely second messenger in several different mitogenic pathways, was highly expressed in tumor tissue of glioblastoma multiforme (9 of 9) and highly anaplastic astrocytoma (2 of 6), but not in astrocytomas of lower pathological grade (0 of 6). We also detected high levels of annexin II expression in fetal brain during the period when radial glia proliferate, although annexin II expression was not detected in normal adult brain. These data demonstrate that annexin II expression is developmentally regulated in the human central nervous system and suggest that the early progenitor radial glia share important characteristics with highly malignant glial tumors.     

Implications of admission hypothermia in trauma patients

Hypothermia is common after severe injury, and has been associated with an increased mortality rate in patients stratified by anatomic indices of injury severity. In this retrospective study of 173 patients, early post-traumatic hypothermia was found to correlate with physiologic indicators of volume deficit, independently of the amount of intravenous fluid received. There was no correlation found between admission core temperature and time from injury, blood alcohol, or presence of severe closed head injury. Hypothermic patients (less than 35 degrees C) had a lower predicted probability of survival and a higher mortality rate than euthermic patients (greater than or equal to 35 degrees C). However, when patients were stratified by physiologic and anatomic indicators of injury severity, mortality rates among the euthermic and hypothermic patients were not significantly different. Early post-traumatic hypothermia does not appear to exert an independent effect upon outcome.     

Paramyosin is the Schistosoma mansoni (Trematoda) homologue of antigen B from Taenia solium (Cestoda)

Antigen B, a major antigen of the cestode parasite Taenia solium, has been purified and a portion of amino acid sequence obtained. Paramyosin of the trematode parasite Schistosoma mansoni, an immunogenic protein that has shown promise as a vaccine candidate, has several biochemical and immunological properties in common with antigen B. A full-length cDNA clone of S. mansoni paramyosin has been obtained and the predicted translation product contains a sequence that is highly homologous to the sequence obtained for antigen B. The predicted amino acid composition and isolectric point of paramyosin are nearly identical to those established for antigen B. Recombinant S. mansoni paramyosin, expressed in Escherichia coli as a fusion protein with beta-galactosidase, was recognized by antisera against T. solium antigen B. We conclude from these results that S. mansoni paramyosin and T. solium antigen B are homologous proteins. Since S. mansoni paramyosin is thought to be a muscle protein and T. solium antigen B a secreted glycoprotein with anti-complement activity, this conclusion raises some interesting questions regarding the role of this class of proteins in the host-parasite relationship.     

An outbreak of cryptosporidiosis associated with a resort swimming pool.

An outbreak of cyptosporidiosis occurred in late April 1993 among resort hotel guests which was temporally associated with, but geographically distant from, a massive waterborne outbreak of cryptosporidiosis in Milwaukee, Wisconsin, that occurred in late March and early April of 1993. A case-control study was performed among groups with members who reported illness and among a systemic sample of groups who stayed at the resort hotel during the risk period. Of 120 persons interviewed, 51 (43%) met the case definition. Swimming in the resort hotel''s pool was significantly associated with case status (OR = 9.8; 95% Cl 3.4, 29.7), as was consumption of ice from the hotel''s ice machines (OR = 2.3; 95% Cl 1.01, 5.2). When analysis was restricted only to laboratory-confirmed cases and controls, swimming pool use was the only risk factor significantly associated with illness (OR = 13.0; 95% Cl 2.6, 88.7). Following waterborne outbreaks of cryptosporidiosis associated with water supplies, swimming pools should be considered as possible ongoing sources for transmission regionally.     

Gastric carcinoma presenting as an exacerbation of ulcers during pregnancy. A case report

Gastric cancer is unusual during pregnancy. Also, because of the physiologic changes that occur with pregnancy, it is rare to see a worsening of peptic ulcers during pregnancy. A patient with an exacerbation of peptic ulcers presented with gastric carcinoma during pregnancy.     

Excitatory amino acid antagonists depress acoustic startle after infusion into the ventral nucleus of the lateral lemniscus or paralemniscal zone

Rats were implanted with bilateral cannulas in an area just medial to the ventral nucleus of the lateral lemniscus, an obligatory relay along the acoustic startle pathway. Bilateral infusions of excitatory amino acid transmitter antagonists into this region (10, 25 or 50 nmol per side) produced a rapid, dose-dependent depression of acoustic startle. gamma-D-Glutamylglycine, gamma-D-glutamylaminomethyl sulfonate and 2-amino-5-phosphonovalerate were equally effective in depressing the startle response over this dose range. These results indicate that excitatory amino acid transmitters play an important role in the expression of acoustic startle at this part of the startle pathway.     

Corneal microsporidiosis. A case report including ultrastructural observations

Stromal keratitis and iritis developed in the left eye of a healthy 45-year-old man with no history of ocular disease, trauma, or contact lens wear. The clinical course over a 2-year period was characterized by progressive central disciform keratitis, recurrent anterior stromal patchy infiltration, and iritis which was partially controlled with topical corticosteroids and broad-spectrum antibiotics. Results of bacterial, viral, fungal, and chlamydial cultures were negative. Results of histopathologic examination of a corneal biopsy specimen and, later, a penetrating keratoplasty specimen showed many extracellular and intracellular spores in degenerating keratocytes. By electron microscopy there were encapsulated oval structures measuring approximately 3.5 to 4 microns in length x 1.5 microns in width. Mature spores had well-developed cell walls that contained two abutted nuclei (diplokaryon) and a redundant polar tubule with six coils. These structures are characteristic of a protozoa in the genus Nosema.