36 research outputs found
Association between tumor necrosis factor alpha-238G/a polymorphism and tuberculosis susceptibility: a meta-analysis study
The study of t-PA, u-PA and PAI-1 genes polymorphisms in patients with abdominal aortic aneurysm
Red cell macrocytosis in hypoxemic patients with chronic obstructive pulmonary disease
Macrocytosis is a common finding in patients with chronic obstructive
pulmonary disease (COPD). The cause for the elevation of mean
corpuscular volume (MCV) in these patients remains elusive. In an
attempt to determine the extent of macrocytosis in COPD patients and
search for possible causative factors, we evaluated the hematologic
parameters, F-cell percentage, blood gases and serum erythropoietin
(Epo) levels in 32 COPD clinically stable patients and 34 sex- and
age-matched non-smoker healthy volunteers. An increased MCV was observed
in almost half of the hypoxemic COPD cases (14/32 or 43.75%), while
erythrocytosis developed to a lesser degree (37.5%). The erythropoietic
response did not correlate with the severity of hypoxia. Moreover, no
significant correlation was found between macrocytosis and hypoxemia or
erythrocytosis and red cell size. In some cases the two phenomena
occurred independently. The F-cell percentage was significantly elevated
in the COPD group (P<0.01) and was associated with MCV values (n=32,
r(s)=0.41, P<0.05). This finding supports the hypothesis we put forward
to explain the macrocytosis often observed in COPD, i.e., that the acute
erythropoietic stress occurring repeatedly in these patients as a result
of the frequent exacerbations may lead to waves of release of relatively
immature, large red cells from the marrow, including an increased number
of F-cells, reflecting the recruitment of normally dormant BFU-E (bursts
forming units of erythrocyte precursors), which maintain the program for
gamma-chain synthesis. The fact that erythrocytosis and macrocytosis,
both being triggered by hypoxemia, do not occur consistently in all COPD
patients indicates that many other factors may also intervene. (C) 2004
Elsevier Ltd. All rights reserved
Quadruple Vessel Coronary Artery Bypass Grafting in a 14-Year-Old Child With Plasminogen Activator Inhibitor-1 4G/4G Gene Polymorphism
Zwillinge mit bilateraler Pulmonalembolie und PAI-1 4G/5G Genpolymorphismus: Ein Fallbericht
Quality and safety measures in transfusion practice: The experience of eight southern/eastern Mediterranean countries
Senescence in cell oxidative status in two bird species with contrasting life expectancy.
Oxidative stress occurs when the production of reactive oxygen species (ROS) by an organism exceeds its capacity to mitigate the damaging effects of the ROS. Consequently, oxidative stress hypotheses of ageing argue that a decline in fecundity and an increase in the likelihood of death with advancing age reported at the organism level are driven by gradual disruption of the oxidative balance at the cellular level. Here, we measured erythrocyte resistance to oxidative stress in the same individuals over several years in two free-living bird species with contrasting life expectancy, the great tit (known maximum life expectancy is 15.4 years) and the Alpine swift (26 years). In both species, we found evidence for senescence in cell resistance to oxidative stress, with patterns of senescence becoming apparent as subjects get older. In the Alpine swift, there was also evidence for positive selection on cell resistance to oxidative stress, the more resistant subjects being longer lived. The present findings of inter-individual selection and intra-individual deterioration in cell oxidative status at old age in free-living animals support a role for oxidative stress in the ageing of wild animals