Medical research and publications are the back-bone for advancing the medical field. We identified the Pubmed medical publications that are affiliated with Libya to shed some light on the contribution of this country's medical community to the PubMed database. All publications affiliated with Libya in the PubMed were counted over a five year period ending December 2006. We also used the same method to obtain data on the PubMed medical publications from Tunisia, Morocco and Yemen. Tunisia had the largest number of PubMed publications among the studied countries: 20.4 publications per million population per year and 7.2 publications per year per one billion US$ GDP. Libya had much fewer publications: 2.4 publications per million population per year and 0.4 publications per one billion US$ GDP. The citation frequency for Libyan published research was very low compared to Tunisian and Moroccan related research. Conclusion: This preliminary analysis shows that medical research output in Libya is about twenty times less than in other countries with similar backgrounds, and that it needs to be enhanced.

Medical research and publications are the back-bone for advancing the medical field. We identified the Pubmed medical publications that are affiliated with Libya to shed some light on the contribution of this country's medical community to the PubMed database. All publications affiliated with Libya in the PubMed were counted over a five year period ending December 2006. We also used the same method to obtain data on the PubMed medical publications from Tunisia, Morocco and Yemen. Tunisia had the largest number of PubMed publications among the studied countries: 20.4 publications per million population per year and 7.2 publications per year per one billion US$ GDP. Libya had much fewer publications: 2.4 publications per million population per year and 0.4 publications per one billion US$ GDP. The citation frequency for Libyan published research was very low compared to Tunisian and Moroccan related research. Conclusion: This preliminary analysis shows that medical research output in Libya is about twenty times less than in other countries with similar backgrounds, and that it needs to be enhanced.

Proteins can be separated according to their molecular sizes and charges, since these factors will determine the speed at which they will travel through a gel. The SDS-PAGE method involves the denaturation of proteins with the detergent sodium dodecyl sulfate (SDS) and the use of an electric current to pull them through a polyacrylamide gel, a process termed polyacrylamide gel electrophoresis (PAGE). SDS binds strongly to proteins, with approximately one detergent molecule binding to two amino acids when SDS is present at 0.1% (1,2). When boiled with SDS, proteins gain a negative charge in proportion to their molecular size, and thus travel in the acrylamide gel according to their molecular sizes. The smaller the size of the running protein, the faster it travels through the pores of the gel Fig. 1 ).

We have previously shown that expression of gp200-MR6, a molecule that is functionally associated with the interleukin-4 receptor (IL-4R), is lost from breast carcinoma cells as malignancy increases. Here we have analysed a series of colorectal carcinoma cell lines and show a similar decrease with increasing malignancy. Moreover, analysis of the HRA-19 cell line, which can exhibit a poorly or a well-differentiated phenotype according to culture conditions, shows that gp200-MR6 is weakly expressed on the former but strongly expressed on the latter. Functional analysis using either IL-4 or monoclonal antibody (MAb) MR6 and the well-differentiated cell line SW1222 revealed that MAb MR6 acts as an agonist for IL-4, with both reagents causing a dose-dependent inhibition of cell division, but greatly enhancing the glandular differentiation of SW1222 in three-dimensional collagen gels. These observations suggest that the gp200-MR6 molecule may act as the product of a tumour suppressor gene and that its loss may be a primary event in tumourigenesis. Int. J. Cancer 71: 605-611, 1997.r 1997 Wiley-Liss, Inc.MAb MR6 is a murine IgG 1 antibody, raised against human thymic stromal cells as part of a study designed to investigate the role of the human thymic microenvironment in T-cell maturation (De Maagd et al., 1985). It stains strongly the cortical epithelium and relatively weakly the macrophages and dendritic cells in frozen tissue sections of human thymus (Larché et al., 1987). Immunoelectron microscopy showed that this labelling was localised mainly on the surface of these cells (von Gaudecker et al., 1996). A single band of approximately 200 kDa (gp200-MR6) was detected from biochemical analysis by immuno-precipitation and Western blotting using lysates from normal thymus (Mat et al., 1990). This m.w. was the same under reducing and non-reducing conditions.In functional studies, it was found that MAb MR6 can completely block the proliferation of helper T cells induced by recombinant interleukin-4 (rIL-4) and can block the IL-4-induced production of IgE by polyclonal B cells in the presence of cloned T cells (Larché et al., 1988). Since MAb MR6 also inhibits the production of IL-4 by antigen-activated T cells, it is likely that the major target in these experiments is the IL-4-producing T-helper (Th2) lymphocyte subset (Imami et al., 1994). These data, together with the molecular characteristics of gp200-MR6 and the finding that MAb MR6 does not block the binding of IL-4 to its receptor (IL-4R), have led to the suggestion that MAb MR6 may recognise a polypeptide chain associated with the 140 kDa IL-4R (CD 124) that is possibly involved in IL-4 signal transduction (Larché et al., 1988). Human IL-4, a 19 kDa cytokine, is produced primarily by CD4 1 and some CD8 1 T cells (Paliard et al., 1988); however, it has also been suggested that IL-4 might be produced by bone marrow stromal cells (King et al., 1988), mast cells (Mitchell et al., 1989) and basophils (Brunner et al., 1993). For B cells, T cells, capillary endothelium a...

Background: Previous studies have shown that histamine skin reactivity (the dimensions of a skin wheal elicited by a prick with histamine 10 mg/ml) in unselected school children has increased in Italy during the past two decades and is higher in Italy than in Poland. Hence this variable can probably be influenced by a changing or different lifestyle. The aim of this study was to compare skin reactivity to histamine and codeine (a marker of histamine releasability from mast cells) in schoolchildren from countries with different lifestyles. Methods: Six previously unstudied unselected populations of 9-year-old schoolchildren (two each from Poland, Italy, and Libya; n = 863 subjects; 49.0% males) were pricked with two concentrations of histamine (10 and 1 mg/ml) and codeine (90 and 9 mg/ml). Results: The higher concentrations of both pharmacologic agents tested yielded significantly different wheal areas in the three countries: Poland < Italy < Libya (histamine, 11.8, 16.1 and 20.7 mm²; codeine, 9.2, 13.2 and 16.2 mm²; p < 0.001 for all comparisons). The lower concentrations elicited almost matching results. Histamine wheal areas correlated closely with areas elicited by codeine in the same individual: angular coefficients of the histamine to codeine regression lines were 0.535, Italy; 0.551, Libya; 0.612, Poland; and 0.581 for the whole population. More histamine was needed to produce a wheal in Poland than in Libya: a 20-mm² wheal required an injected histamine concentration of about 8.8 mg/ml in Libya, 29.5 mg/ml in Italy and 102.1 mg/ml in Poland. Conclusion: More studies are necessary to explain the observed international differences in skin histamine reactivity and their effect on the prevalence of positive allergen skin tests.