Red cell glucose-6-phosphate dehydrogenase deficiency in Finland. Characterization of a new variant with severe enzyme deficiency.

Severe red cell glucose-6-phosphate dehydrogenase (G-6-PD) deficiency has been found in an 'aboriginal' Finnish family. 2 male and 9 female carriers of the variant G-6-PD were studied. The genetic pattern is consistent with x-linked recessive inheritance and the defect is associated with drug (primaquine) induced haemolysis. This was demonstrated by enzyme deficient red cell (51Cr-labelled) survival studies on a normal volunteer recipient. In addition, one of the hemizygotes studied had a slight chronic nonspherocytic haemolytic disorder. The partially purified enzyme had many of the characteristics of G-6-PD Mediterranean. The occurrence of this G-6-PD Mediterranean type variant in the Finnish population, which differs greatly from Mediterranean ethnic groups, as well as the association of slight chronic haemolysis with severe G-6-PD deficiency is discussed.     

Possible role for mast cell-derived cathepsin G in the adverse remodelling of stenotic aortic valves

Aims Aortic stenosis (AS) is characterized by extensive remodellingof the valves, including infiltration of inflammatory cells,extracellular matrix degradation, and fibrosis. The molecularmechanisms behind this adverse remodelling have remained obscure.In this article, we study whether cathepsin G, an angiotensinII (Ang II)-forming elastolytic enzyme, contributes to progressionof AS. Methods and results Stenotic aortic valves (n=86) and controlvalves (n=17) were analysed for cathepsin G, transforming growthfactor-ß1 (TGF-ß1), and collagens I andIII with RT–PCR and immunohistochemistry. Valvular collagen/elastinratio was quantified by histochemistry. In stenotic valves,cathepsin G was present in mast cells and showed increased expression(P<0.001), which correlated positively (P<0.001) withthe expression levels of TGF-ß1 and collagens I andIII. TGF-ß1 was also present in mast cell-rich areasand cathepsin G induced losartan-sensitive TGF-ß1expression in cultured fibroblasts. Collagen/elastin ratio wasincreased in stenotic valves (P<0.001) and correlated positivelywith smoking (P=0.02). Nicotine in cigarette smoke activatedmast cells and induced TGF-ß1 expression in culturedfibroblasts. Fragmented elastin was observed in stenotic valvescontaining activated cathepsin G-secreting mast cells and innormal valves treated with cathepsin G. Conclusion In stenotic aortic valves, mast cell-derived cathepsinG may cause adverse valve remodelling and AS progression.     

Fall in the prevalence of chronic gastritis over 15 years: analysis of outpatient series in Finland from 1977, 1985, and 1992.

To investigate whether the occurrence of chronic gastritis (and Helicobacter pylori acquisition) has changed in Finland in the past 15 years, the prevalence rates of chronic gastritis in biopsy specimens in consecutive series of outpatients (aged 20 or more) who had undergone diagnostic upper gastrointestinal endoscopy in 1977 (702 patients), 1985 (1309 patients), or 1992 (1447 patients) were compared. The prevalences of gastritis in these series were also compared with that in a random sample (438 subjects) of people who underwent endoscopy in 1974-76. It seemed that the prevalence of gastritis was significantly lower in the outpatients in 1992 than in the random endoscopy sample in 1974-76. The reduction was most noticeable in young age groups (20-49 years) in which the decline was 38% (drop from 66% to 41%). In addition, it seemed that the prevalence of gastritis was very dissimilar in different birth cohorts. The prevalence was high (70-80%) in 1977, 1985, and 1992 in the cohorts born at the beginning of the century and lower (40-50%) in those born during later decades. The prevalence rates had remained unchanged in the same cohorts over the 15 years (from 1977 to 1992) suggesting that the people had mainly been infected with H pylori and contracted gastritis before the age of 20. In conclusion, gastritis is a cohort phenomenon and its prevalence has fallen in Finland in the last 15 years. This decrease is caused by a decline of the rate of H pylori acquisition in birth cohorts, particularly in childhood and adolescence (below age of 20).     

Lymphangiogenesis in aortic valve stenosis--novel regulatory roles for valvular myofibroblasts and mast cells

ObjectiveTo investigate mechanisms of lymphangiogenesis in aortic valve stenosis (AS).MethodsLymphatic vessels were visualized with LYVE-1 staining in 20 control, 5 sclerotic, and 40 stenotic human aortic valves. Vascular endothelial growth factors (VEGFs) VEGF-C and VEGF-D, and their lymphangiogenic receptor VEGFR-3, and the angiogenic VEGFR-2 were analysed by quantitative real-time PCR and immunohistochemistry. Cultured myofibroblasts derived from human stenotic aortic valves, and cultured human mast cells were used to study VEGF-C regulation, and VEGF-C and VEGF-A were quantified from cell culture media by enzyme immunoassays.ResultsLymphatic vessels, VEGF-C, VEGF-D, VEGFR-3 and VEGFR-2 all were present in the aortic valves. In AS, the number of lymphatic vessels and the expression of VEGF-D, VEGFR-3, and VEGFR-2 were increased. Moreover, the numbers of lymphatic vessels correlated positively with those of neovessels (r = 0.525, p = 0.001) and mast cells (r = 0.374, p = 0.017). Cultured valvular myofibroblasts produced VEGF-C, and addition of tumour necrosis factor alpha (TNF-α) to the cells augmented its secretion. In contrast, proteases released by activated human mast cells degraded VEGF-C.ConclusionThese results show that lymphangiogenesis is induced in advancing AS. Furthermore, valvular myofibroblasts and activated mast cells were identified as novel regulators of lymphangiogenesis in aortic valves.