LONG‐TERM FOLLOW UP OF PATIENTS WITH SMALL GASTROINTESTINAL STROMAL TUMORS IN THE STOMACH USING ENDOSCOPIC ULTRASONOGRAPHY‐GUIDED FINE‐NEEDLE ASPIRATION BIOPSY

Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.     

Use of amiodarone during pregnancy.

Five cases are studied in which amiodarone (AM) was given during pregnancy, in two of them also during the breast feeding period, to estimate the risks for adverse effects. We measured the concentrations of AM and its major metabolite desethylamiodarone (DEA) in maternal plasma, cord plasma, infant plasma, placental tissue and breast milk and the thyroid hormones were measured in maternal and neonatal serum. Also, the neonates were examined for AM-associated adverse effects over a period varying from 8 months up to 5 years. We observed a limited maternal-fetal transfer of AM and DEA, while the concentration of DEA in placental tissue is relatively high. Considerable amounts of AM and DEA were present in breast milk. One infant appeared to be hypothyroid, detected by the neonatal thyroid screening. He was treated with triiodothyronine for weeks, until it was clear that the thyroid dysfunction was resolved. The other infants had normal screening results. No effect of the AM medication was observed on growth, liver function or cornea and skin. In conclusion: although pregnancy and lactation are no absolute contraindications for use of AM, special precautions are necessary. It is unavoidable that in some cases the pregnant mother, and especially her infant, becomes hypothyroid. AM has to be administered in the lowest possible dose, and the maternal and neonatal thyroid function must be controlled as long as the exposure to AM lasts.     

Occupational stress management programmes: a practical overview of published effect studies

There are many occupational stress management programmes availablewhich are designed to prevent and cure the negative aspectsof job-stress. The focus of the programmes can be directed towardsthe individual worker, the working group, the organization ofthe work or the organization as a whole. Moreover, programmesshow a considerable variation with respect to the type of interventionsthey promote and their underlying assumptions, as well as theirduration and costs. In this paper, effect studies of occupationalstress programmes published between 1987 and 1994 are reviewed.The aim is to give a practical overview of the variety in occupationalstress programmes, their scope, applicability and the evidenceof their effectiveness. The paper updates the review by DeFrankand Cooper published in 1989.     

Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces

A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence.     

Competitive control of the self-renewing T cell repertoire

We develop a mathematical model for the self-renewing part of the T cell repertoire. Assuming that self-renewing T cells have to be stimulated by immunogenic MHC-peptide complexes presented on the surfaces of antigen-presenting cells, we derive a model of T cell growth in which competition for MHC-peptide complexes limits T cell clone sizes and regulates the total number of self-renewing T cells in the animal. We show that for a sufficient diversity and/or degree of cross-reactivity, the total T cell number hardly depends upon the diversity of the T cell repertoire or the diversity of the set of presented peptides. Conversely, for repertoires of lower diversity and/or cross-reactivity, steady-state total T cell numbers may be limited by the diversity of the T cells. This provides a possible explanation for the limited repertoire expansion in some, but not all, mouse T cell re-constitution experiments. We suggest that the competitive interactions described by our model underlie the normal T cells numbers observed in transgenic mice, germ-free mice and various knockout mice.