Markers of oxidative damage of nucleic acids and proteins among workers exposed to TiO2 (nano) particles

OBJECTIVE

The use of nanotechnology is growing enormously and occupational physicians have an increasing interest in evaluating potential hazards and finding biomarkers of effect in workers exposed to nanoparticles.

METHODS

A study was carried out with 36 workers exposed to (nano)TiO2 pigment and 45 controls. Condensate (EBC) titanium and markers of oxidation of nucleic acids (including 8-hydroxy-2-deoxyguanosine (8-OHdG), 8-hydroxyguanosine (8-OHG), 5-hydroxymethyl uracil (5-OHMeU)) and proteins (such as o-tyrosine (o-Tyr), 3-chlorotyrosine (3-ClTyr) and 3-nitrotyrosine (3-NOTyr)) were analysed from samples of their exhaled breath.

RESULTS

In the production workshops, the median total mass 2012 and 2013 TiO2 concentrations were 0.65 and 0.40 mg/m(3), respectively. The median numbers of concentrations measured by the scanning mobility particle sizer (SMPS) and aerodynamic particle sizer (APS) were 1.98 × 10(4) and 2.32 × 10(4) particles/cm(3), respectively; and about 80% of those particles were smaller than 100 nm in diameter. In the research workspace, lower aerosol concentrations (0.16 mg/m(3) and 1.32 × 10(4) particles/cm(3)) were found. Titanium in the EBC was significantly higher in production workers (p<0.001) than in research workers and unexposed controls. Accordingly, most EBC oxidative stress markers, including in the preshift samples, were higher in production workers than in the two other groups. Multiple regression analysis confirmed an association between the production of TiO2 and the levels of studied biomarkers.

CONCLUSIONS

The concentration of titanium in EBC may serve as a direct exposure marker in workers producing TiO2 pigment; the markers of oxidative stress reflect the local biological effect of (nano)TiO2 in the respiratory tract of the exposed workers.

Transient anorexia, hyper-nociception and cognitive impairment in early adjuvant arthritis in rats

OBJECTIVE

Rheumatoid arthritis (RA) is associated with enhanced pro-inflammatory cytokine levels, pain, anorexia, and cognitive changes. The enhanced production of cytokines appears before the full manifestation of the disease. So far, any experimental data on behavioral effects of early arthritis are lacking. In the present series we describe anorexia early changes in, pain hyper-sensitivity and altered cognitive behavior during the first four days of adjuvant arthritis in rats (AA), when no clinical signs are yet apparent.

METHODS

AA was induced to male Lewis rats by a single injection of complete Freund's adjuvant (cFA) at the base of the tail. Plasma leptin and ghrelin were measured using specific RIA methods. Gene expressions for food-regulatory peptides, neuropeptide-Y (NPY) and interleukin-1β (IL-1β) in the hypothalamic arcuate nuclei (nARC), were quantitated by TaqMan real-time PCR. Pain sensation was measured on all four limbs and tail by the plantar test. Cognitive functions were tested in the Morris water maze (MWM).

RESULTS

Levels of orexigenic ghrelin as well as mRNA expression of orexigenic NPY in nucleus arcuatus (nRC)re significantly enhanced on day 2 of AA only. Reduced body weight and food intake persisted by day 4 with the most profound reduction on day 2. The mRNA for anorexigenic IL-1β in the nARC was significantly enhanced on days 2 and 4. Enhanced pain sensitivity was observed on day 2, as was the cognitive impairment given by longer time to find the hidden platform, longer time spent in thigmotaxis zone, and longer trajectory. The less effective strategy used to find the hidden platform was observed up to the day 4 of AA.

CONCLUSIONS

Early stage of AA brings about reduced body weight, food intake, and activation of central orexigenic pathways. The observed anorexia could be ascribed to the over-expression of anorexigenic IL-1β which dominates over the NPY orexigenic effects. On day 2 of AA higher pain sensitivity and cognitive impairment appear. All the observed change tend to recover by day 4 of the disease.

Transrectal ultrasound and magnetic resonance imaging in staging of early cervical cancer

The goal of this study was to determine the sensitivity, specificity, and accuracy of transrectal ultrasound (TRUS) in comparison to magnetic resonance imaging (MRI) in the evaluation of tumor volume, early parametrial infiltration, and identification of residual tumor in early-stage cervical cancer. Patients in whom an early-stage cervical cancer was diagnosed by clinical examination were enrolled in the study. Only those patients who were examined by both MRI and TRUS with following surgical treatment were included. Imaging results were compared with pathology findings. Altogether, 120 patients were consecutively enrolled from January 2004 to February 2006. Data from 95 patients were evaluated. Correlation coefficient for TRUS- and MRI-derived volumes versus volumes at pathology reached R = 0.996 and R = 0.980, respectively. The accuracy for detecting tumor in 95 patients was 93.7% for TRUS and 83.2% for MRI (P <or= 0.006). In small tumors (<or=1 cm(3)), the accuracy of tumor detection by TRUS was 90.5% and 81.1% by MRI (P <or= 0.049). The accuracy of parametrial infiltration detection by TRUS and MRI was 98.9% and 94.7%, respectively (P <or= 0.219). The accuracy was not influenced by body mass index values. In conclusion, our results showed the accuracy of TRUS as being comparable to the more commonly used MRI in staging of early-stage cervical cancer. TRUS and the pathology-derived volumes correlated tightly; accuracy of TRUS was superior to MRI, especially in detection of residual tumors following conization.

[Analysis of district evolution from the point of view of annual components of relative population growth]

"This article characterizes the population evolution within the 76 districts of the Czech Republic based on annual time series of crude measures of natality, mortality, emigrations and immigrations since 1951. It aims at evaluation of the individual development of relative population growth distributed by both components of natural change and migrations. Extrapolation of annual component measures until 2000 based on principles of exponential smoothing (discounted weighted linear regression) is the [focus] of the article." (SUMMARY IN ENG AND RUS)

[Comprehensive treatment of crural ulcers]

The authors present 65 patients treated in the stage C6 of chronic venous insufficiency. Conservative therapy was performed in the cases with large ulcers associated with crural edema. Recovery was observed in 47 cases (73%) during 5 months. Recurrence authors in 3 patients (5%) and the treatment was not successful in 7 cases (10%). In 8 patients primary or secondary surgical treatment was performed. The average period of treatment was 1.6 months. (Tab. 1, Ref. 24.)

[Pedal bypass in the treatment of arterial occlusive disease of the lower extremities in diabetics]

BACKGROUND

The increase of the number of diabetics in the population and prolongation of their survival increases also the number of patients suffering from diabetic foot syndrome. Terminal complication of diabetic foot syndrome is diabetic gangrene, which is the cause of 50% of major amputations performed in Slovak republic. The problem of major amputations is not only medical, but also economic one. Adequate treatment can reduce the number of amputations by 50%. One of the possibilities to improve the prognosis of a diabetic suffering from obliterative macroangiopathy is the treatment by distal bypass, because with the regard to the characteristic distribution of the lesions to leg arteries is the classic vessel surgery (aortofemoral and femoropopliteal/femorocrural bypasses) inefficient. After the introduction of this treatment at our department preliminary results and some prognostic factors of the surgery success were evaluated.

AIM OF THE STUDY

To evaluate the efficiency of pedal bypass as a method of treatment for peripheral obliterative atherosclerosis in diabetics and to determine the predictive value of paraclinical investigations and angiography.

METHODS

Retrospective analysis of clinical, paraclinical and functional parameters of patients in whom pedal bypass was indicated, focused on the analysis of angiography.

RESULTS

Of the 142 patients hospitalised with diabetic foot complications 32 were indicated for pedal bypass. All the patients were in the IV stage according to Fontain, the range of gangrene reached in average 2.7 grades of Wagners scale. Early success--i.e. functional artery reconstruction after hospital discharge was achieved in 18 patients (56%). Positive criteria for early success of the surgery involve short interval from gangrene development and serum albumin level above 26 g/l as an indicator of the nutritional state. Favourable angiographic criteria were: passage free arteries of dorsum pedis (ADP, ATP, a. plantaris, ATA) in the length of 10 cm free from focal stenoses, presence of numerous collaterals of legs and dorsum pedis, opacification of metatarsal and digital arteries.

CONCLUSION

Pedal bypass is an efficient method of treatment for obliterative processes of lower extremities in diabetics with involvement of leg arteries. On the basis of our results this procedure can be recommended after careful preoperative staging and analysis of angiography as the method of treatment. It is necessary to perform the operation as soon as possible regarding the worsened nutritional and healing potential of the organism in the case of gangrene. Providing the surgery is properly indicated and performed it significantly improves the life quality of the patient. (Tab. 5, Fig. 1, Ref. 22.)

Optimization of demographic models with Poissonian response

"The general solution of related estimation and inference problems we can specify as application of Fisher scoring algorithm for maximum likelihood estimators with constraints (in Section 2).... Application to regional fertility patterns (in Section 3) yields the simultaneous solutions of tasks about structural fertility differentiations which have not been presented with correct stochastic evaluation.... The functions used for approximations of age-specific fertility schedules coincide with the most usual types of curves described in demographic literature...." (SUMMARY IN CZE)