Relationship of demethylation processes to veratric acid concentration and cell density in cultures of Rhodococcus erythropolis

The aim of this study was to investigate the correlation between veratrate degradation, veratric acid concentration and cell density in Rhodococcus erythropolis cultures. The optimum culture conditions for veratrate demethylation proved to be a cell density of A(660)=1 and a concentration of 0.02% veratrate. All the products of demethylation (i.e. vanillic and protocatechuic acids) were found to be present and correlated with the appearance of high levels of free radicals and formaldehyde after contact of the cells with veratrate. Demethylation was accompanied by oscillatory changes in the levels of endogenous oxygen uptake and phenolic products. Changes in veratrate concentration and cell density caused a disturbance in the demethylation process and also in the efficiency of phenolics, formaldehyde and reactive oxygen species.     

Association of serum Clara cell protein CC16 with respiratory infections and immune response to respiratory pathogens in elite athletes

Background

Respiratory epithelium integrity impairment caused by intensive exercise may lead to exercise-induced bronchoconstriction. Clara cell protein (CC16) has anti-inflammatory properties and its serum level reflects changes in epithelium integrity and airway inflammation. This study aimed to investigate serum CC16 in elite athletes and to seek associations of CC16 with asthma or allergy, respiratory tract infections (RTIs) and immune response to respiratory pathogens.

Methods

The study was performed in 203 Olympic athletes. Control groups comprised 53 healthy subjects and 49 mild allergic asthmatics. Serum levels of CC16 and IgG against respiratory viruses and Mycoplasma pneumoniae were assessed. Allergy questionnaire for athletes was used to determine symptoms and exercise pattern. Current versions of ARIA and GINA guidelines were used when diagnosing allergic rhinitis and asthma, respectively.

Results

Asthma was diagnosed in 13.3% athletes, of whom 55.6% had concomitant allergic rhinitis. Allergic rhinitis without asthma was diagnosed in 14.8% of athletes. Mean CC16 concentration was significantly lower in athletes versus healthy controls and mild asthmatics. Athletes reporting frequent RTIs had significantly lower serum CC16 and the risk of frequent RTIs was more than 2-fold higher in athletes with low serum CC16 (defined as equal to or less than 4.99 ng/ml). Athletes had significantly higher anti-adenovirus IgG than healthy controls while only non-atopic athletes had anti-parainfluenza virus IgG significantly lower than controls. In all athletes weak correlation of serum CC16 and anti-parainfluenza virus IgG was present (R = 0.20, p < 0.01). In atopic athletes a weak positive correlations of CC16 with IgG specific for respiratory syncytial virus (R = 0.29, p = 0.009), parainfluenza virus (R = 0.31, p = 0.01) and adenovirus (R = 0.27, p = 0.02) were seen as well.

Conclusions

Regular high-load exercise is associated with decrease in serum CC16 levels. Athletes with decreased CC16 are more susceptible to respiratory infections. Atopy may be an additional factor modifying susceptibility to infections in subjects performing regular high-load exercise.     

Efficient induction of apoptosis by proteasome inhibitor: bortezomib in the human breast cancer cell line MDA-MB-231

The cellular and molecular effects of the proteasome inhibitor—bortezomib—on breast cancer cells are as yet poorly characterised. Bortezomib selectively induces apoptosis in some cancer cells. However, the nature of its selectivity remains unknown. Previously, we demonstrated that: there was no effect of bortezomib action on apoptosis and a time-dependent increase in senescence of human skin fibroblasts. The study presented here provides novel information on cellular effects of bortezomib in breast cancer cells line MDA-MB-231. Our findings demonstrated that in contrast to normal fibroblasts, bortezomib treatment evoked a strong effect on apoptosis in breast cancer cells incubated in hypoxic and normoxic conditions. We observed a time-dependent increase up to 70 % in apoptosis of MDA-MB-231 cells in hypoxic and normoxic conditions. There was no effect of bortezomib action on senescence of these cells. We suggest that bortezomib may be candidates for further evaluation as chemotherapeutic agents for human breast cancer.