Effect of storage and ultraviolet B irradiation on CD14-bearing antigen- presenting cells (monocytes) in platelet concentrates

BACKGROUND: Ultraviolet B (UVB) irradiation of platelet concentrate (PCs) reduces platelet alloimmunization, but the mechanism of the effect is unclear. Evidence suggests that UVB may downregulate the expression of surface adhesion molecules on passenger antigen- presenting cells in PCs. STUDY DESIGN AND METHODS: The effect of blood bank storage, platelet preparation from whole blood, and UVB irradiation on the quantitative expression of intercellular adhesion molecule-1 (ICAM-1, or CD54), HLA-DR, CD45, and CD11c on CD14-positive antigen-presenting cells (monocytes) was studied by using two-color flow cytometry. RESULTS: Blood bank storage for 4 days resulted in upregulation of ICAM-1 and HLA-DR and downregulation of CD14 but left the expression of CD11c and CD45 unchanged. Preparation of PCs from fresh whole blood was associated with a rapid increase in CD11c without upregulation of ICAM-1 and HLA-DR. UVB irradiation before storage inhibited the upregulation of ICAM-1 and HLA-DR, resulted in accelerated downregulation of CD14, and was associated with increased loss of monocytes. Agitation of the PC bag during irradiation was of critical importance, since omission of agitation resulted in largely uninhibited upregulation of ICAM-1 but was still associated with significantly higher cell loss than that seen in unirradiated controls. CONCLUSION: UVB exposure nonspecifically affects monocytes in PCs, resulting in downregulation of surface molecules that are important for antigen presentation, as well as in significant cell loss.     

Intimal fibromuscular dysplasia and Takayasu arteritis: delayed response to percutaneous transluminal renal angioplasty

Percutaneous transluminal renal angioplasty has been shown to be an effective technique to dilate renal artery lesions, particularly those due to fibromuscular dysplasia. However, four of 70 patients in this study experienced atypical responses to angioplasty. Their lesions initially resisted dilation and had incomplete dilatation immediately after angioplasty. Long-term follow-up (1 week to 2 years) angiograms, however, demonstrated fully dilated arteries. In cases of focal nonatherosclerotic lesions from intimal or adventitial fibroplasia, initial incomplete dilatation may be satisfactory in the long term whereas repeated inflations may result in undesirable complications.     

Increased granulocyte aggregation in vitro in diabetes mellitus

Having previously shown an increase in white blood cell (WBC) aggregation in groups known to have a high incidence of cardiovascular events, we compared 28 patients with diabetes mellitus and no history or clinical evidence of macrovascular disease with 28 age- and sex- matched normal controls. Patients and controls had blood taken in the morning and analysed for WBC aggregation in vitro using a whole blood technique. WBC aggregation was significantly higher in the diabetic group compared with the normal controls (mean +/- SD 31.10 +/- 10.26% vs. 25.7 +/- 9.38%; p < 0.04, Student t-test). WBC aggregation predates the appearance of clinical symptoms of macrovascular disease in diabetes.      

A preliminary evaluation of ankle orthoses in the management of children with cerebral palsy

The effectiveness of ankle-foot orthoses (AFOs) on walking pattern was studied in 12 children with cerebral palsy between the ages of 3 and 7 years. Over a 2-year period two trials of fortnightly periods without AFOs were carried out. The range of ankle dorsiflexion, video analysis looking specifically at footfall, and rank scoring of the mediolateral shear force obtained using an oscilloscope printout from a Kistler force platform were compared with measurements obtained during periods when the child was wearing AFOs. The results using different outcomes were consistent, and indicated that the range of movement and gait deteriorated during the two trial periods during which the splints were not worn compared with periods during which the splints were worn. This finding needs to be confirmed in a large randomised controlled trial.     

Liver volume measurements and three-dimensional display from MR images

A method was investigated for measuring the volumes of human livers in vivo from magnetic resonance images and subsequently displaying these livers in three dimensions. Volumetric image sets of phantoms, healthy volunteers, and patients with cirrhotic livers were processed. Two image-processing approaches were compared for accuracy of liver measurements, intrasubject and interobserver variation, and speed of processing. Results indicated that both processing methods had a high degree of volume-measuring accuracy (within 8%), the interobserver measurements had a high coefficient of correlation (r = .9994), the intrasubject measurements had a low coefficient of variation (1.8%), and one method was four to five times faster than the other. The faster and easier of the two image-processing approaches provided satisfactory results for measuring liver volumes, but the slower approach provided more realistic-looking three-dimensional images of the liver.     

Rectal sensitivity in chronic constipation

Rectal sensitivity is often reduced in patients affected by chronic constipation, but it is not known whether this alteration differs according to the severity and the site(s)of the slowing of gastrointestinal transit. Moreover, it is not known whether alteration precedes or follows bowel complaints. In this study, perception of intrarectal distension was evaluated in 28 healthy controls, in 20 patients complaining of constipation and with a normal gastrointestinal transit time (<96hr),and in 44 patients complaining of constipation and with a prolonged gastrointestinal transit time (>96hr).Within the latter group,perception to intrarectal distension was analyzed in patients with slowing of transit in the rectum only, in the colon only, and in both the rectum and the colon. In a subgroup of 22 patients, rectal sensitivity was evaluated before and after treatment. Rectal sensitivity was found to be reduced significantly in constipated patients;it was more severely reduced in patients with objective evidence of prolonged gastrointestinal transit time and with slow transit in the rectum. Rectal sensitivity improved in patients who responded to treatment and did not vary significantly in nonresponders.