Treatment of acute lymphoblastic leukemia-induced extreme hypercalcemia with pamidronate and calcitonin.

OBJECTIVE: To describe extreme hypercalcemia as the presenting feature of acute lymphoblastic leukemia in an 8-yr-old girl and the combined use of pamidronate and calcitonin for its treatment. DESIGN: Case report. SETTING: Pediatric intensive care unit. PATIENT: An 8-yr-old girl with 20.0 mg/dL serum calcium (reference range, 8.8-10.4 mg/dL) and 2.66 mmol/L ionized calcium (reference range, 1.13-1.32 mmol/L). INTERVENTION: Intravenous pamidronate and subcutaneous calcitonin. MEASUREMENTS AND MAIN RESULTS: Our patient presented with nausea, vomiting, lethargy, weight loss, fatigue, and weakness but, remarkably, did not exhibit electrocardiographic changes. Initial treatment with hydration at 8 mL x kg(-1) x hr(-1) and furosemide was ineffective. A single dose of 1 mg/kg intravenous pamidronate given over 24 hrs complemented by three doses of 5 units/kg subcutaneous calcitonin over 36 hrs lowered serum calcium to a normal range within 3 days. Side effects noted were hypocalcemia, hypomagnesemia, and hypophosphatemia. They were most pronounced 7-9 days after treatment, stabilized with supplementation, and returned to acceptable ranges by 1 month without need for ongoing electrolyte supplements. A renal computed tomographic scan did not show nephrocalcinosis. The patient remained free from recurrence of hypercalcemia 6 wks after initiating chemotherapy for acute lymphoblastic leukemia. CONCLUSIONS: Extreme hypercalcemia can be a presenting feature of acute lymphoblastic leukemia, but it may not result in life-threatening organ dysfunction. Combined treatment with pamidronate and calcitonin should be considered for treating hypercalcemia that does not respond to conventional therapy with hydration and furosemide.

Active learning of respiratory physiology improves performance on respiratory physiology examinations.

Active involvement in the learning process has been suggested to enhance creative thinking, judgement, interpretation, and problem-solving skills. Therefore, educators are encouraged to create an active-learning environment by incorporating active-learning strategies into the class. However, there is very little documentation of the effectiveness of active-learning strategies. Furthermore, faculty are often reluctant to incorporate new strategies without documentation of the effectiveness of these strategies. To address this concern, we compared the performance of two individual classes on an identical respiratory physiology examination. One class was taught respiratory physiology using active-learning strategies. The other class was taught respiratory physiology using the traditional lecture format. The results document that students who learned using active-learning strategies did significantly better (P < 0.05) on the respiratory physiology examination than students who learned by the traditional lecture format (61 +/- 2.2 vs. 86 +/- 1.0). Thus, by actively involving students in the learning process, academic performance is enhanced.

Naturally occurring rearranged taxoids.

The rearranged taxoids have recently been reported from different Taxus species. The literature concerning the chemistry, biogenesis, and bioactivity of such compounds is reviewed.

Molecular and functional characterization of recombinant human metabotropic glutamate receptor subtype 5.

We have isolated and characterized overlapping cDNAs that encode two isoforms of the human metabotropic glutamate receptor subtype 5 (hmGluR5). The deduced amino acid sequences of human and rat mGluR5a are 94.5% identical. However, a region in the putative cytoplasmic domain (SER926-ALA1121) displays significant sequence divergence. Genomic analysis of this region showed that the sequence divergence results from species-specific differences in the genomic sequences, not from alternative splicing. The distribution of mGluR5 mRNA in human brain was most strongly detected throughout the hippocampus, with moderate levels in the caudate-putamen, cerebral cortex, thalamus, and deep cerebellar nuclei, and at low levels in the cerebellar cortex. Activation of both hmGluR5a and hmGluR5b transiently expressed in Xenopus oocytes and HEK293 cells was coupled to inositol phosphate (InsP) formation and elevation of the intracellular free calcium ([Ca2+]i). The agonist rank order of potency for activating recombinant hmGluR5a receptors in either system was quisqualate > L-glutamate > 1S,3R-ACPD. Both the quisqualate stimulated InsP and [Ca2+]i were inhibited by (+)-MCPG. Recombinant human mGluR5a was also stably expressed in mouse fibroblast Ltk- cells, in which the efficacy and potency of quisqualate were unchanged for more than 30 cell passages.