Relationship between Field Strength and Abnormal Development in Chick Embryos Exposed to 50 Hz Magnetic Fields

Summary

Chick embryos were exposed to sinusoidally oscillating 50 Hz magnetic fields during their first 2 days of development. In the first series of experiments magnetic field strengths of 0·1, 0·3, 1 and 10 A/m were used. The percentage of abnormal embryos (%AE) was 16 per cent in the sham-exposed control group. %AE was increased at 1 A/m (29 per cent) and 10 A/m (32 per cent), but not at 0·1 A/m (16 per cent) or 0·3 A/m (14 per cent). In the second series of experiments field strengths of 0·4, 0·6, 0·9 and 1·35 A/m were used. %AE was 17 per cent in the control group, 10 per cent at 0·4 A/m, 19 per cent at 0·6 A/m, 17 per cent at 0·9 A/m and 36 per cent at 1·35 A/m. Only the 1·35 A/m group was significantly different from the controls. The results of this study suggest that exposure of chick embryos to a 50 Hz magnetic field causes abnormal development, and that no abnormalities are induced below a threshold between 0·9 and 1 A/m.     

Post-traumatic meningioma: three case reports of this rare condition and a review of the literature

We present three cases of meningiomas developing at the site of an old head trauma. We then review the literature regarding the controversies on the development of post-traumatic brain tumors and, finally, we emphasize the medico-legal characteristics of post-traumatic meningiomas, particularly with respect to their cell type which is frequently atypical or anaplastic and which have a poor outcome.     

Availability of iron and degree of inflammation modifies the response to recombinant human erythropoietin when treating anemia of chronic disease in patients with rheumatoid arthritis

Forty-six patients with rheumatoid arthritis (RA) and documented anemia of chronic disease (Hb <100/110 g/l) were randomized to receive either human recombinant erythropoietin (r-HuEPO, n = 36, 300 U/kg body weight) or placebo (n = 10) for 12 weeks in a multicenter study. An adequate response was defined as elevation of Hb≥120 g/l. Relevant clinical and laboratory assessments were made to evaluate efficacy and secure safety. A significant elevation in Hb from week 10 onwards was noted in twenty-six patients (five drop-outs) out of nine patients receiving placebo (one drop-out) (12±1.2 g/l vs 4±0.5 g/l; Hb elevation from 95 g/l to 107 g/l vs 93 g/l to 97 g/l, P<0.05). Only 14.6%, however, were considered responders according to preset criteria. In the responders a lower initial CRP, a significant reduction in ESR but not in CRP was seen compared to the remaining r-HuEPO group. A significant elevation of energy level was noted in the r-HuEPO group; otherwise, no differences in clinical variables were seen. No serious adverse effects were noted. When analyzing patients receiving oral iron in combination with r-HuEPO and adding five additional, openly selected patients receiving both adequate iron supplementation and r-HuEPO, there was a significant weekly elevation of Hb from week 8 onwards in favor of combination therapy over the ones only receiving r-HuEPO (18±1.1 g/l vs 7±1.1 g/l, P<0.05). The initial six responders had now reached ten of whom seven belonged to the combination therapy group. Response to r-HuEPO in RA patients appears to be dependent on availability of iron and on the degree of inflammation. If r-HuEPO treatment is considered, iron deficiency should always be corrected and strenous efforts should have been made to control the disease itself. Received: 21 February 1997 / Accepted: 21 April 1997     

Substance use-related outpatient consultations in specialized health care: an underestimated entity

Background To study the occurrence and documentation of substance use related outpatient visits in specialized health care.
Methods The diagnosis recorded in retrospective discharge data in Tampere University Hospital for 6 years was compared with the prospective data gathered from separately completed forms added during an 8-week period to every outpatient's discharge data. In this form, the relation of substance use and the actual reason for the consultation were specifically elicited.
Results On the basis of diagnoses, retrospectively, 0.4% (6,666 of 1,555,898) of outpatient visits were caused by substance use. In the prospective part of the study, 5.6% of visits (1,401/25,014) were related to substance use. Retrospective study demonstrated 2% prevalence of substance use, whereas prospective study showed 36% substance use–related visits at the emergency room. According to the retrospective discharge data, alcohol-related organ damages were the major reason for substance use–related outpatient visits. In the prospective study, the proportion of acute traumas was most prevalent.
Conclusions Our study indicates that substance use–related visits often remain undetected in specialized health care. Substance use–related visits were underdocumented/undetected in the emergency room. Using a simple separate form could dramatically increase the detection of substance use–related visits.     

Diagnostic and prognostic significance of autoantibodies in early rheumatoid arthritis

A positive rheumatoid factor (RF) test has been included as one of the criteria for the diagnosis of rheumatoid arthritis (RA) according to the 1987 classification criteria of the American College of Rheumatology (ACR). During the past 20-30 years many different autoantibodies have been described in patients with RA. The presence of some of the autoantibodies in RA directed against various autoantigens, such as anti-neutrophil cytoplasmic antibodies, anti-nuclear antibodies, antibodies against interleukin-1 (IL-1), anti-cardiolipin antibodies, and antibodies against oxidized low density lipoprotein, is not specific for RA and these are not discussed here. This review summarizes the most relevant autoantibodies, and discusses their sensitivity, specificity, and possible diagnostic and prognostic significance in early RA. The antibodies are presented with the two clinically most relevant antibody tests first, followed by others in alphabetic order.     

Sera from patients with heparin-induced thrombocytopenia generate platelet-derived microparticles with procoagulant activity: an explanation for the thrombotic complications of heparin-induced thrombocytopenia

Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.