17 research outputs found
Airway neutrophilia in COPD is not associated with increased neutrophil survival
Neutrophilic airway inflammation is a prominent feature of chronic obstructive pulmonary disease (COPD) and correlates with disease severity. The mechanisms that determine the extent of neutrophilia could involve increased influx or prolonged survival of neutrophils. We wanted to assess whether neutrophil pro-survival mechanisms are increased in the airways of subjects with COPD due to the presence of anti-apoptotic factors in the bronchial lining fluid.Induced sputum samples were collected from 20 subjects with stable COPD, 14 healthy smokers and 14 healthy controls. Quantification of apoptotic neutrophils was based on typical morphological cell changes. The anti-apoptotic, pro-survival activity in the sputum was studied by culturing peripheral blood neutrophils with the fluid phase of induced sputum. Apoptosis was assessed both by morphology and flow cytometry using Annexin-7AAD staining. COPD-patients and healthy smokers had a significantly higher percentage of sputum neutrophils than healthy controls (p<0.0001, p=0.01). However, there were no significant differences between the three subject groups in either the proportion of apoptotic neutrophils in sputum or the in vitro anti-apoptotic activity detected in the sputum fluid phase. Prolonged survival of neutrophils in sputum is not a feature of COPD and cannot explain the increased numbers of airway neutrophils in this disease
Antioxidant enzymes in renal cell carcinoma
The aim of the study was to estimate the
significance of oxidative/nitrosative damage and
expression of antioxidant enzymes in renal cell
carcinomas (RCC). For this we investigated
immunohistochemically six antioxidant enzymes
(AOEs) including MnSOD, ECSOD, thioredoxin,
thioredoxin reductase, and gammaglutamyl cysteine
synthetase heavy and light chain in 138 RCCs. As an
indicator of oxidative/nitrosative damage, sections were
stained with an antibody to nitrotyrosine. The extent of
apoptosis was evaluated by TUNEL method and
proliferation by immunohistochemistry to Ki67. Variable
expression of all AOEs could be seen in RCC with
expression of MnSOD being strongest. Nitrotyrosine
was significantly associated with high grade tumors.
MnSOD was associated with tumors of a lower stage.
Cases showing ECSOD reactivity had higher and cases
expressing thioredoxin lower apoptotic index than other
tumors. No association with patient prognosis was
observed. According to the results renal cell carcinomas
show oxidative/nitrosative damage which, according to
nitrotyrosine staining, was higher in high grade tumors.
Of AOEs, MnSOD was more abundantly expressed in
low stage tumors suggesting that its antioxidant function
could play a main role to prevent development of
oxidative damage leading to more aggressive tumors