The role of multi-parton interactions in doubly-heavy hadron production.

Beauty and charm quarks are ideal probes of pertubative Quantum Chromodymanics in proton-proton collisions, owing to their large masses. In this paper the role of multi-parton interactions in the production of doubly-heavy hadrons is studied using simulation samples generated with Pythia, a Monte Carlo event generator. Comparisons are made to the stand-alone generators BcVegPy and GenXicc. New methods of speeding up Pythia simulations for events containing heavy quarks are described, enabling the production of large samples with multiple heavy-quark pairs. We show that significantly higher production rates of doubly-heavy hadrons are predicted in models that allow heavy quarks originating from different parton-parton interactions (within the same hadron-hadron collision) to combine to form such hadrons. Quantitative predictions are sensitive to the modelling of colour reconnections. We suggest a set of experimental measurements capable of differentiating these additional contributions.

Extended storage of whole blood before the preparation of blood components: in vitro effects on red blood cells in Erythro-Sol environment.

BACKGROUND AND OBJECTIVES: Routine procedures for extended storage of whole blood (WB) before the preparation of blood components are of interest primarily for logistical reasons. We stored red cell units in either Erythro-Sol 2 (E-Sol 2, test units, 150 ml added) or in saline-adenine-glucose-mannitol (SAG-M) (reference units, 100 ml added) that were prepared after storage of WB at room temperature for 8, 12, 16 or 19 h after blood collection. STUDY DESIGN AND METHODS: Red blood cells were stored for 42 days. We measured pH, glucose, lactate, haemolysis, red blood cell adenosine triphosphate and 2,3-diphosphoglycerate on days 1, 7, 14, 21, 28, 35 and 42. RESULTS: Haematocrits were significantly lower in E-Sol 2 than in SAG-M due to the higher volume of E-Sol 2 added compared to SAG-M. Significantly reduced levels were found in E-Sol 2 of extracellular pH (throughout storage after 8-h hold and initially after 12-, 16- or 19-h hold), of lactate (initially after 8-h hold and throughout storage after 12-, 16- or 19-h hold), and of haemolysis from day 35 in the 8-h and on day 42 in the 12-h hold group. Significantly increased levels of adenosine triphosphate were seen in E-Sol 2 after 8-h hold (from day 14) and after 12-h hold (at days 21, 35 and 42) compared to SAG-M. Significantly higher concentrations of 2,3-diphosphoglycerate were noticed primarily after 8-h hold of WB. CONCLUSION: The use of E-Sol 2 as a replacement for SAG-M does not significantly improve in vitro data after extended storage of WB at room temperature before preparation of blood components. However, after 8-h hold in vitro characteristics similar to or better than in fresh blood will be maintained for several weeks in E-Sol 2, a situation that makes E-Sol 2 superior to SAG-M when storage of WB is limited to 8 h. Some improvement was noted after 12-h hold as well.

Automated preparation of platelet concentrates from pooled buffy coats: in vitro studies and experiences with the OrbiSac system.

BACKGROUND: The aim was to evaluate platelet concentrates (PCs) prepared by the automated OrbiSac system, from pooled buffy coats (BCs) stored in a platelet (PLT) additive solution. STUDY DESIGN AND METHODS: Experiment 1 was a paired in vitro study of PCs (from six BCs), prepared by automated and manual procedures. Experiments 2 and 3 evaluated PCs from OrbiSac (from six BCs); Experiment 3 included selection of BCs based on donor data. Experiment 4 was a paired in vitro study of PCs (from six BCs) with an integrated white blood cell (WBC) filter and two different storage containers. Experiment 5 evaluated PCs (from six BCs) from the OrbiSac with an integrated WBC filter. Experiment 6 was similar to Experiment 5 with computer-selected pools of 5 BCs. The in vitro studies evaluated the effects of 7-day storage of PLTs regarding PLT metabolism and disintegration. RESULTS: Experiments 1 and 4 had similar in vitro results. In Experiment 2, PLT content was 370 x 10(9) +/- 70 x 10(9) per PC and recovery from BCs was 76 +/- 6 percent. In Experiment 3, the PLT content was 380 x 10(9) +/- 50 x 10(9) per PC and variation was reduced compared with randomly pooled BCs. In Experiment 5, increased PLT content was found (420 x 10(9) +/- 70 x 10(9) per PC and recovery from BCs of 80 +/- 5%). In Experiment 6, five rather than six BCs gave 340 x 10(9) +/- 60 x 10(9) PLTs per PC and recovery was 79 +/- 5 percent. CONCLUSION: These in vitro studies suggest that the OrbiSac technique is equivalent to the standard manual method regarding the PLT in vitro characteristics during storage for 7 days. The results of standardizing the PLT count in PCs by selecting the BCs pools on the basis of the blood donor PLT concentration were encouraging.

Storage of platelets in additive solutions: a pilot in vitro study of the effects of potassium and magnesium.

BACKGROUND AND OBJECTIVES: Platelet additive solutions (PAS) have been shown to be suitable for extended platelet storage but have required the carryover of substantial (30%) amounts of plasma for success. Improving platelet quality by optimizing the composition of PAS may allow a reduction to be made in the amount of plasma carried over. Reducing the proportion of plasma carried over would facilitate some methods of viral inactivation and make available greater amounts of plasma for other needs. MATERIALS AND METHODS: Platelets from six pools of 25 buffy coat platelet units and five apheresis platelet units were aliquoted for storage in plasma, or converted to PAS units in either a specific additive solution (PAS-III), with 30% or 20% plasma, or a modification of PAS-III containing 5.0 mm potassium and 1.5 mm magnesium (PAS-IIIM), with 30% or 20% plasma. Units were stored at room temperature with agitation for 7 days with in vitro testing for biochemical, haematological and functional parameters. RESULTS: Storage of platelets in PAS-IIIM resulted in a reduced rate of glycolysis and better retention of pH, morphology score and ATP levels. Platelets initially showed less evidence of activation when stored in PAS-IIIM, with reduced P-selectin expression. Storage in PAS-IIIM with 20% (rather than the standard 30%) plasma appeared to result in the retention of in vitro properties, similarly to storage in standard PAS-III with 30% plasma. CONCLUSIONS: Storing platelets in an additive solution containing magnesium and potassium improves the functionality of the platelets, as measured by in vitro testing, and may allow a reduction of the amount of plasma required to be carried over to the final unit.

Differential modulation of transforming growth factor-beta by betamethasone-17- valerate and isotretinoin: corticosteroid decreases and isotretinoin increases the level of transforming growth factor-beta in suction blister fluid.

Retinoids and glucocorticoids are known to have a potential to modulate the expression of transforming growth factor-beta (TGF-beta). We investigated the effect of oral isotretinoin (13-cis-retinoic acid) on the expression of two distinct isoforms of TGF-beta, TGF-beta1 and TGF-beta2, in suction blister fluid and serum in acne patients. We also investigated the effect of topical glucocorticoid (betamethasone-17-valerate) and age on suction blister fluid TGF-beta1 in healthy volunteers. Six weeks of isotretinoin treatment caused a statistically significant 19% increase in suction blister fluid TGF-beta1. The suction blister fluid TGF-beta2 level remained below the sensitivity level of the immunoassay in many cases. Isotretinoin did not affect the serum TGF-beta1 or TGF-beta2 level. Betamethasone-17-valerate pretreatment for 3 days twice a day caused a statistically significant 17% decrease in suction blister fluid TGF-beta1. The active form of TGF-beta1 represented 5% of the total TGF-beta1 in suction blister fluid. Our diffusion calculations suggest that all TGF-beta1 and TGF-beta2 detected in suction blister fluid have diffused from systemic circulation. The increase in suction blister fluid TGF-beta1 after isotretinoin treatment seems to be of local origin, while the decrease in suction blister fluid TGF-beta1 after glucocorticoid pretreatment seems to be due to glucocorticoid-induced vasoconstriction resulting in decreased diffusion of TGF-beta1 from the circulation. Modulation of local interstitial fluid TGF-beta1 concentration may be one mechanism by which isotretinoin and glucocorticoids mediate their effects in skin.

Re-epithelialization rate and protein expression in the suction-induced wound model: comparison between intact blisters, open wounds and calcipotriol-pretreated open wounds.

We have investigated re-epithelialization following induction of suction blisters in humans in intact blisters, open wounds, i.e. blister roofs removed immediately after blister induction, and calcipotriol-pretreated open wounds. Intact blisters simulate blister healing in bullous disease, while open wounds simulate re-epithelialization during wound healing. Re-epithelialization was clearly faster in open wounds than in intact blisters, and was not affected by calcipotriol pretreatment. Bullous pemphigoid antigen 2 (BP180), bullous pemphigoid antigen 1 (BP230), plectin/hemidesmosomal 1 protein (HD1), laminin 5, laminin alpha5, laminin beta1, type VII collagen, tenascin-C, beta4, alphavbeta5, alpha5 and alpha9 integrins were studied in intact blisters and open wounds by immunohistochemistry. Hemidesmosomal plaque proteins BP230 and plectin/HD1, which connect the keratin cytoskeleton to the hemidesmosome, appeared earlier at the leading edge in intact blisters than in open wounds. Band-like immunostaining in the basement membrane for laminin 5, alpha5 and beta1 chains was continuous in blister bases, but partially discontinuous in open wound bases. The other antigens studied showed similar expression in intact blisters and open wounds. BP180, BP230, plectin/HD1, beta4 integrin, laminin 5 and tenascin-C expression were further studied in calcipotriol-pretreated open wounds. Calcipotriol did not affect the expression of these antigens. The immunohistochemical results suggest that the keratin cytoskeleton is linked to the basal plasma membrane of migrating basal cells via BP230 and plectin/HD1 earlier in the more slowly re-epithelializing blisters than in open wounds. An intact laminin sheath may inhibit keratinocyte migration in intact blisters.

Wine, alcohol, and oral health, with special emphasis on dental erosion.

Wine is an essential component of the Mediterranean diet. Its consumption is increasing in many industrialized countries due to effective marketing. Wine may also have effects in the oral cavity mainly due to its acidity and alcohol content. This article briefly describes some effects of wine, both beneficial and detrimental, on oral and general health. In particular, the effect of wine on tooth enamel is demonstrated.

Fibroblast growth factor-mediated stimulation of differentiating teratocarcinoma cells: evidence for paracrine growth regulation.

Tera 2 human embryonal carcinoma cells proliferate rapidly in culture but are capable of differentiating into quiescent cells with neuronal features. We have characterized the effects of exogenous and endogenous fibroblast growth factors on the proliferation of differentiating Tera 2 cells. Exogenous basic fibroblast growth factor (bFGF) stimulated DNA synthesis and induced the proliferation-associated antigen Ki 67 in differentiated Tera 2 cells. Heparin-binding growth factors isolated from the undifferentiated cells excerted a similar stimulatory effect on their differentiated derivatives. The functional potential of these endogenous growth factors was further demonstrated by their ability to stimulate plasminogen activator production by capillary endothelial cells. A major part of the growth promoting activity was removed by absorption with immobilized bFGF antibodies. bFGF was also detected in Tera 2 cells by immunoblotting. The production of heparin-binding growth-promoting activity decreased during differentiation. The results demonstrate a potential role for heparin-binding growth factors in the autocrine or paracrine growth regulation of teratocarcinoma cells.

Plasma zinc and copper concentrations in rheumatoid arthritis: influence of dietary factors and disease activity.

Forty patients with rheumatoid arthritis performed a thorough 7-d diet recording. The food diaries were analyzed together with clinical and laboratory data by means of stepwise multiple linear regression to clarify the effects of both diet and the inflammatory disorder on the plasma concentrations of zinc and copper. The patients' daily dietary intakes of zinc and copper (24.3 +/- 7.54 and 3.48 +/- 1.55 mg/MJ) were comparable to the corresponding intakes in the ordinary Finnish diet (24.0 and 3.68 mg/MJ). In multivariate analyses the best predictors of plasma trace elements were the measures of disease activity and not the dietary factors. As an exception to this, there was a strong correlation between plasma copper-copper intake ratio and zinc intake both in univariate (r = -0.638, P less than 0.001) and multivariate analysis. This suggests that zinc depresses copper absorption with intakes in normal, physiological ranges.