BRCA2 founder mutation in Slovenian breast cancer families

Linkage analysis has identified BRCA1 and BRCA2 germline mutations as the major cause for cancer predisposition in breast and/or ovarian cancer families. In previous screening efforts on Belgian families we had a BRCA1/2 gene mutation detection rate of 25%.(1) Here we report the results of a BRCA mutation screening in seven high-risk breast/ovarian cancer families from Slovenia. We found a single but highly recurrent BRCA2 splice site mutation (IVS16-2A>G) in three breast cancer-only families. This cancer-linked mutation could not be identified in three families with ovarian cancer, suggesting that the mutation predisposes at least predominantly to breast cancer. All mutation carriers shared a common disease associated haplotype indicating a founder effect. This mutation most probably occurred in a single ancestor and seems essentially confined to the Slovene population.     

Micromolar concentrations of EGTA increase histamine secretion from mast cells treated with digitalis glycosides of different polarity

Histamine release from rat peritoneal mast cells induced by compound 48/80 (1 g/ml) after 90 min of preincubation in calcium — free medium is only 8.4%. Cardiotonic glycosides modify the secretion induced by compound 48/80: hydrophlic glycosides potentiate the secretion, and this potentiation decreases with increasing lipophility of the glycosides.Our present study shows that the preincubation (90 min) of mast cells with EGTA (1mol/l) potentiates the histamine release induced by compound 48/80. A further potentiation is found when mast cells are preaincubated with EGTA before the addition of digitalis glycosides. The potentiation depends on the polarity of the glycoside. Since EGTA inflences the secretion only in media containing sodium, the effect of EGTA might be due to its interaction with membrane permeability for Na⁺ ions. Liposoluble glycosides have an additional intracellular effect, acting on microfilaments and producing a lower or no potentiation of the response.     

Changes in histamine secretion from mast cells caused by digitalis glycosides.

Cardiotonic glycosides modify histamine secretion from rat mast cells in the following way. (1) Preincubation (30 min) of mast cells with liposoluble glycosides (10(-4) mol/l) increases the spontaneous histamine secretion by about 5%. (2) Preincubation of mast cells with 10(-4) mol/l liposoluble glycosides (digitoxin, digoxin, digitoxigenine) decreases histamine release induced by compound 48/80 in the presence of calcium, whereas the water soluble glycoside, strophanthin G, has no effect on the secretion. (3) Preincubation of mast cells in a calcium-free medium with the glycosides (10(-4) mol/l) has a dual-effect on histamine secretion induced by compound 48/80: water soluble glycosides (strophanthin G and K) potentiate histamine release, whereas the liposoluble glycosides (digitoxin, digitoxigenine) decrease the secretory response. The difference in the activity of different glycosides could be explained by their dual effects, namely an inhibition of Na+K(+)-ATPase which leads to an increase in histamine release, and intracellular action(s) of liposoluble glycosides leading to a decrease of histamine secretion.     

Escherichia coli biofilm formation and dispersion under hydrodynamic conditions on metal surfaces

The aim of this study was to analyze the impact of hydrodynamic forces on the multiplication of E. coli, and biofilm formation and dispersion. The experiments were provided in a flow chamber simulating a cleaning-in-place system. Biofilm biomass was measured using a crystal violet dye method. The results show that hydrodynamic forces affect not only biofilm formation and dispersion but the multiplication of E. coli in the first place. We found more biofilm biomass on the rough surface than on the smooth one. The results of the biofilm formation test show that laminar flow promotes the biofilm growth over 72 h, meanwhile turbulent flow after 48 h causes decrease in biomass. The results of the biofilm dispersion test, in contrast, show that laminar flow removed less biofilm from both materials that turbulent flow did. Therefore, taking into account these findings in cleaning-in-place technology can substantially reduce E. coli multiplication and biofilm formation.     

Uncommon combination of multiple myeloma in three patients

The authors describe uncommon combinations of multiple myeloma in three men aged 83, 63 and 55 years. In patient no. 1 both diseases--pernicious anaemia and multiple myeloma IgG-kappa were detected simultaneously. In patient no. 2 Crohn's disease preceded multiple myeloma IgA-lambda by more than 30 years. In patient no. 3 Gaucher's disease preceded multiple myeloma with paraproteinaemia IgA-lambda and IgG-kappa by more than 10 years. The diagnosis was facilitated by examination of the bone marrow, immunochemical examination of serum and urine and X-ray examination of the skeleton. In all patients the development of the myeloma had an adverse effect on the general course of the disease and despite treatment it soon proved fatal. In the discussion views on the possible causal associations between these diseases are discussed.