Purification of eosinophil peroxidase and studies of biosynthesis and processing in human marrow cells

Human eosinophil peroxidase (EPO) was purified from leukocytes obtained from a patient with hypereosinophilia. EPO was extracted from the granule fraction using 0.2 mol/L sodium acetate pH 4.0, and the extract was subjected to gel chromatography on Sephadex G-75 and ion exchange chromatography on Biorex 70. The mol wt calculated from gel chromatography was approximately 50,000. However, under reducing and denaturing conditions, polyacrylamide gel electrophoresis revealed two subunits with mol wt of 50,000 and 15,000. The biosynthesis of EPO was studied in marrow cells from patients with eosinophilia using labeling with (14C)-leucine, followed by immunoprecipitation with anti-EPO, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and fluorography for visualization of labeled EPO. Biosynthesis of an Mr 53,000 subunit was demonstrated. Biosynthetic labeling of the Mr 15,000 subunit was not demonstrated. A labeled Mr 25,000 chain was detected and may represent a degradation product or a chain that, after further modification, produces the Mr 15,000 subunit. Labeling was also detected in two polypeptides with mol wt of 78,000 and 72,000. These forms of EPO seem to represent precursor polypeptides subjected to proteolytic processing in a similar manner as has been reported for myeloperoxidase (MPO). However, Monensin, a proton ionophore, which blocks the processing of MPO, did not inhibit processing of EPO, indicating separate mechanisms by which MPO and EPO are directed to granules.     

The effects of tandem skiing on posture and heart rate in children with profound intellectual and multiple disabilities

Purpose: The objective of study was to determine the effect of tandem ski (TS) activity on postural control and cardiac activity in children with profound intellectual and multiple disabilities (PIMDs).

Method: Twenty children with PIMD and 20 age-matched controls (typically developed (TD) children) participated. Body segment movements were measured with inertial sensors (Physilog®) placed on the head, C7, trunk (including ECG) and pelvis with a seat reference. Each participant was measured during a 12-turn slalom pattern.

Results: In each group, significant differences were observed between the head vs. trunk and head vs. pelvis angular speeds (p<0.001). In both groups, heart rate differed significantly during rest (PIMD 99 bpm, TD 97 bpm), exercise (PIMD 140 bpm, TD 139 bpm; rest vs. exercise p<0.001) and recovery (PIMD 101 bpm, TD 107 bpm; exercise vs. recovery p<0.001).

Conclusions: In children with PIMD, TS elicits active postural control associated with cardiac activities similar to that of the controls.     

An exploratory study of disease surveillance systems in Norway

We conducted a qualitative study of the system for contagious disease surveillance in Norway. Semi-structured interviews were held with five general practitioners (GPs), including one person responsible for informing GPs in their region about potentially serious disease outbreaks. The interviews suggested that the existing system had several limitations, making it of little relevance to local epidemics or daily medical practice. Specifically, it was difficult and time-consuming for physicians to locate relevant information, and there was a substantial delay between reported diagnoses and eventual feedback about outbreaks. This resulted in information that was too old to be of value. The interviews also investigated design matters related to future realtime disease surveillance systems. The GPs expressed interest in a distributed system for realtime extraction and presentation of data from electronic record systems. They required that any such system be customizable to the specific needs of the doctor in order to be relevant in day-to-day practice, and that correct interpretation of data would be possible in the minimum of time.