Red cell 2,3-DPG,ATP, and mean cell volume in highly trained athletes

Summary 20 male elite long distance runners were compared to a control group of blood donors to determine the effect of training on red blood cells. The acute effects of exercise on red cells were investigated in 11 of the runners following a race of 15–30 km. The runners had elevated resting values of red cell 2,3-DPG (P<0.05) and mean cell volume (P<0.01); blood Hb and ATP were not different from concentrations in the control group. The red cell status of the athletes may be explained by an increased proportion of young erythrocytes in runners. No statistically significant changes in red cell 2,3-DPG, ATP, mean cell volume or blood Hb were found post exercise.     

SpecialEscherichia coli serotypes among enterotoxigenic strains from diarrhoea in adults and children

106 enterotoxigenicEscherichia coli strains from children and adults from many parts of the world were serotyped for O and H antigens. Some OH types,i.e. O6H16, O8H9, O15H11, O25H42, O78H11 and O78H12, were found repeatedly from different geographical locations. Some of these OH serotypes were only found rarely among more than 20000E. coli strains collected over many years from different locations and sources. It is suggested that these special OH serotypes represent clones which have been selected to the special conditions in the small intestine and selected to carry the plasmids necessary to provoke diarrhoea.     

In silico model-driven assessment of the effects of single nucleotide polymorphisms (SNPs) on human red blood cell metabolism

The completion of the human genome project and the construction of single nucleotide polymorphism (SNP) maps have lead to significant efforts to find SNPs that can be linked to pathophysiology. In silico models of complete biochemical reaction networks relate a cell's individual reactions to the function of the entire network. Sequence variations can in turn be related to kinetic properties of individual enzymes, thus allowing an in silico model-driven assessment of the effects of defined SNPs on overall cellular functions. This process is applied to defined SNPs in two key enzymes of human red blood cell metabolism: glucose-6-phosphate dehydrogenase and pyruvate kinase. The results demonstrate the utility of in silico models in providing insight into differences between red cell function in patients with chronic and nonchronic anemia. In silico models of complex cellular processes are thus likely to aid in defining and understanding key SNPs in human pathophysiology.     

Intra- or inter-specific difference in genotypes of Caligus elongatus Nordmann 1832?

Two mitochondrial and one nuclear genetic marker were used to study the phylogenetic position of the two reported CO1-genotypes of Caligus elongatus in a group of closely related caligid parasites. Molecular analysis of the two mitochondrial genes (CO1 and 16S), indicate genetic distances of the two C. elongatus genotypes in the lower range of distances previously reported between other crustacean species, but higher than comparable reported within-species differences. Analyses of nuclear 18S sequences indicate no detectable differentiation between these genotypes, but may be due to expected differences in the resolution of these genetic markers. Investigation of two of three selected morphological characters reveals phenotypes supporting the division based on the molecular division. The species status on the two C. elongatus genotypes cannot be drawn conclusively, although the molecular and morphological data presented here suggests the presence of sibling species.     

The phosphatidylinositol 3-kinase/protein kinase B signaling pathway is activated by lipoteichoic acid and plays a role in Kupffer cell production of interleukin-6 (IL-6) and IL-10

Sepsis caused by gram-positive bacteria lacking lipopolysaccharide (LPS) has become a major and increasing cause of mortality in intensive-care units. We have recently demonstrated that the gram-positive-specific bacterial cell wall component lipoteichoic acid (LTA) stimulates the release of the proinflammatory cytokines in Kupffer cells in culture. In the present study, we have started to assess the signal transduction events by which LTA induces the production of tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and the anti-inflammatory cytokine IL-10 in rat Kupffer cells. LTA was found to trigger phosphorylation of mitogen-activated protein kinases (MAPK) (p38 MAPK and ERK 1/2) and protein kinase B (PKB). Compared to LPS, LTA was more potent in inducing PKB phosphorylation after 40 min, although we found that the cytokine responses were similar. For both bacterial molecules, blocking phosphatidylinositol 3-kinase (PI3-K; Ly294002) or Janus kinase 2 (JAK-2; AG490) particularly affected the induction of IL-6 and IL-10 release, whereas TNF-alpha levels were strongly reduced by inhibition of Src family tyrosine kinases (PP2). All three cytokines were reduced by inhibition of p38 MAPK (SB202190) or the broad-range tyrosine kinase inhibitor genistein, whereas IL-6 release was particularly blocked by inhibition of ERK 1/2 (PD98059). Divergences in the regulatory pathways controlling TNF-alpha, IL-10, and IL-6 production in Kupffer cells following LPS or LTA stimulation may create a basis for understanding how the balance between pro- and anti-inflammatory cytokines is regulated in the liver following infections by gram-positive or gram-negative bacteria.     

Diagnosis of mold allergy

Conclusion The problems of elucidating the role of mold spores in allergy are related to both an absence of detailed information about allergen exposure, and lack of standardized allergen extracts. Provided qualitatively and quantitatively optimal extracts are available, the IgE-diagnostic tests are of equal value in diagnosing mold sensitization, as with other aeroallergens. In the opinion of the author, the specific diagnosis represents the combination of demonstrated IgE reactivity (using diagnostic tests) and clinical symptoms related to exposure to the causative allergen. In order to diagnose organ-specific disease, an unequivocally positive challenge in the relevant shock organ is essential. The rational approach to diagnosing mold allergy is, based on the clinical history, to use skin test as the primary screening test. SPT has the highest sensitivity (few false negative reactions) and, compared to ICT, few irrelevant positive reactions, and should consequently be used to screen for IgE sensitization in the diagnostic workup. Because of the lower sensitivity, RAST is not optimal as the initial test, but as a result of high specificity (few false positive reactions) it is optimal as a confirmatory test for the presence of specific IgE. The clinical relevance of the IgE sensitization should be confirmed by reevaluating the history to ensure that the patients do in fact have symptoms caused by the allergen (Table 2). Challenge tests are normally indicated only if the diagnosis of allergen sensitization implies therapeutic interventions, such as allergen-specific immunotherapy.