Human immune responses to the highly repetitive Plasmodium falciparum antigen Pf332.

The B and T cell responses to EB200, a repetitive part of the Plasmodium falciparum antigen Pf332, were examined in malaria-exposed Senegalese adults. Most donors had high levels of antibodies to recombinant EB200 and 17 overlapping peptides spanning EB200. Taking proliferation and/or cytokine (interferon-gamma and interleukin-4) production as a measure of T cell activation, eight of the EB200-derived peptides induced responses in > 40% of the donors tested. There was no general association between the different types of T cell responses measured, emphasizing the importance of including multiple parameters when analyzing T cell responses and suggesting that EB200 induces functionally distinct T cell responses. The most efficient peptide for induction of proliferative responses was one previously shown to induce T cell responses in five different H-2 congenic mouse strains primed with EB200, suggesting that this is a universal T cell epitope. The presence of multiple B and T cell epitopes in EB200, widely recognized by humans, is important since EB200 has been shown to elicit protective antibody responses in monkeys and may be considered for inclusion in malaria subunit vaccines.     

Pin-tract complications in external fixation of fractures of the distal radius

We analyzed retrospectively the rate and outcome of pin-tract complications in 314 unstable fractures of the distal radius, treated with the Hoffmann small-frame external fixator. The overall rate of complications was 27%. The commonest complication (21 %) was pin-tract infection, which was treated with oral antibiotics. There were no cases of osteitis. Complications led to premature removal of the fixator in 17 of the cases. Women over the age of 75 years had a significantly higher rate of pin loosening (17%), but not a higher rate of premature removal of the fixator due to complications. 4% of the cases had a pin-site fracture, all women. The rate of pin-tract complications was high, but severe complications were rare, even in old women.     

Marked alterations in retinoid homeostasis of Sprague-Dawley rats induced by a single i.p. dose of 10 micrograms/kg of 2,3,7,8-tetrachlorodibenzo-p-dioxin

Interference of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in retinoid homeostasis was investigated in Sprague-Dawley rats with a low (dietary induced) retinoid status, that were fed a [3H]retinol-containing diet (37 MBq, 10,000 IU/kg diet) for 21 days to facilitate determination of retinoid concentrations in various tissues. The rats were exposed to a single i.p. dose of 10 micrograms TCDD/kg body weight in corn oil, or to corn oil at day 7 of [3H]retinol supplementation. TCDD induced significant reductions in retinol and retinyl ester concentrations and [3H] retinol-derived radioactivity in the liver, the lung, the intestine and the adrenals to 3-5%, 40-45%, 37%, and 56% of control values, respectively, at 14 days after exposure. In contrast, the retinoid concentrations and the amount of [3H]retinol-derived radioactivity in the kidney and serum of TCDD-treated rats was increased to 440% and 140% of corn oil-treated controls, respectively, at the termination time of the experiment. Analysis of the amount of serum retinol binding protein (RBP) by gel-permeation chromatography revealed an 150% increase in the free fraction of retinol-RBP, i.e., uncoupled to transthyretin (TTR), in serum of TCDD-treated rats. In addition, urinary excretion of [3H]retinol-derived radioactivity was significantly enhanced (to 140% of controls) by TCDD. These data indicate that TCDD induces an increased mobilization of retinoids from hepatic and extrahepatic storage sites into serum accompanied by an enhanced elimination via the kidney into the urine of rats.     

Effect of heparin on the substrate utilization during prolonged exercise

Leg and splanchnic exchange of free fatty acids (FFA) and glucose was determined during 90 min bicycle exercise after heparin administration in six healthy male volunteers, and the results compared to those obtained previously under identical exercise conditions without the administration of heparin. Heparin elicited a marked elevation of plasma FFA at rest but the exercise values were not higher than during exercise without prior heparin administration. The FFA uptake in the exercising legs was, however, augmented after heparin due to an increase in the fractional leg uptake. Leg glucose uptake and splanchnic glucose production during exercise were not affected by heparin administration. It is concluded that inhibition of glucose uptake by FFA is of minor importance in the regulation of muscle substrate utilization during exercise in man.     

Experience of physical activity in patients with fibromyalgia and chronic widespread pain

PURPOSE: Patients with fibromyalgia (FM) and chronic widespread pain (CWP) find physical activity troublesome. The purpose was to develop a questionnaire to investigate the experience of physical activity in FM and CWP populations. METHOD: A questionnaire was developed from a qualitative study. After that, a total of 204 patients with FM or CWP completed the questionnaire. A factor analysis was conducted and the internal consistency was investigated. The relationship between the factors and pain, health status (the Fibromyalgia Impact Questionnaire, FIQ), distress (the Hospital Anxiety and Distress scale, HAD) and leisure time physical activity (the Leisure Time Physical Activity Instrument, LTPAI) was investigated. RESULTS: Five factors were identified: Physical Relaxation (PR), Well-being (WB), Activity Beliefs (AB), Activity-related Symptoms (AS) and Activity Habits (AH). Cronbach's alpha ranged from 0.57 to 0.86. The PR showed a correlation (rho 0.28, p < 0.01) with the FIQ Pain. The AS showed a correlation (rho 0.25, p < 0.01) with the FIQ total score, while the AH showed a correlation with the HAD Depression (0.26, p < 0.01) and with strenuous physical activity (LTPAI) (-0.32, p < 0.01). CONCLUSION: A new instrument was developed to study the experience of physical activity in persons with long-lasting pain. Five factors were identified using factor analysis, and three of them showed fair associations with FM symptoms, distress or physical activity.     

Contribution of hip strength indices to hip fracture risk in elderly men and women.

In this prospective, case-control study, femoral neck diameter, cross-sectional moment of inertia, or section modulus was an independent predictor of hip fracture risk after adjustment for BMD. However, the contribution of each of these indices to hip fracture prediction was modest in the presence of BMD. INTRODUCTION: The relative contribution of measures of hip strength to hip fracture prediction is unclear. This study was designed to characterize the association between hip strength indices and hip fracture risk in relation to BMD in elderly men and women. MATERIALS AND METHODS: Seventy-one women and 25 men>or=60 years of age, who sustained a hip fracture during the study period of 1989-2003, were selected from the prospective, population-based Dubbo Osteoporosis Epidemiology Study. These fracture cases were randomly matched for age and sex in a 1:2 ratio with nonfracture individuals. BMD at the femoral neck was measured before the fracture event by DXA (Lunar DPX-L). Hip strength indices, including femoral neck diameter (FND), cross-sectional moment of inertia (CSMI), and section modulus (Z), were estimated by reanalysis of the image files using hip strength analysis software. RESULTS: In women, after adjustment for BMD, increased risk of hip fracture was associated with smaller FND (OR, 1.6; 95% CI, 1.0, 2.7), lower CSMI (OR, 1.8; 95% CI, 1.0, 3.2), or Z (OR, 1.6; 95% CI, 1.1, 5.1). In men, none of these hip strength indices were significant predictors of fracture risk. However, using the results in women as a prior distribution, it was estimated that the BMD-adjusted OR for FND (OR, 1.5; 95% CI, 1.0, 2.3), CSMI (OR, 1.6; 95% CI, 1.0, 2.5), or Z (OR, 2.3; 95% CI, 1.4, 3.9) was each significantly associated with hip fracture risk in men. In the logistic regression model, BMD alone accounted for 32% and 16% of the variance of fracture liability in women and men, respectively. The addition of FND, CSMI, or Z to the model increased the respective variance proportion to 34% and 19%. CONCLUSIONS: These data suggest that smaller FND and lower CSMI or Z is an independent risk factor for hip fracture in both women and men. However, the contribution of these measures to hip fracture prediction over and above BMD is likely modest.