Radioiodine therapy accelerates apoptosis in peripheral blood lymphocytes of patients with differentiated thyroid cancer.

Both apoptosis and micronuclei formation reflect cytogenetic damage in cells and could contribute to cell homeostasis. The aim of this study was to evaluate apoptosis in peripheral blood lymphocytes (PBLs) of patients with differentiated thyroid cancer (DTC) before and after 131-iodine (131-I)-therapy and its correlation with micronuclei (MN) frequency. The study population included 18 DTC patients and 18 healthy donors. Apoptotic cells were detected using the Annexin V-FITC/7-AAD kit and MN frequency by cytokinesis-block MN assay. The difference between early apoptosis in PBLs of DTC patients before therapy and controls (9.88 ± 4.99% vs. 6.64 ± 2.07%, p = 0.003) was significant, as well as between early apoptosis in PBLs of DTC patients before and after 131-I-therapy (9.88 ± 4.99% vs. 13.53 ± 6.57%, p = 0.008). The MN frequency and early apoptosis in PBLs of DTC patients was positively correlated before (r = 0.540, p= 0.021) and after 131-I-therapy (r = 0.585, p= 0.014). Thyroid cancer patients had a significantly increased early apoptosis in PBLs, which further increased after 131-I-therapy in association with MN frequency.

Short term priming effect of brain-actuated muscle stimulation using bimanual movements in stroke.

OBJECTIVE: Brain-computer interface triggered-functional electrical stimulation (BCI-FES) is an emerging neurorehabilitation therapy post stroke, mostly for the affected hand. We explored the feasibility of a bimanual BCI-FES and its short-term priming effects, i.e. stimuli-induced behaviour change. We compared EEG parameters between unimanual and bimanual movements and differentiated the effect of age from the effect of stroke. METHODS: Ten participants with subacute stroke, ten age-matched older healthy adults, and ten younger healthy adults underwent unimanual and bimanual BCI-FES sessions. Delta alpha ratio (DAR) and brain symmetry index (BSI) were derived from the pre- and post- resting-state EEG. Event-related desynchronization (ERD) and laterality index were derived from movement- EEG. RESULTS: Participants were able to control bimanual BCI-FES. ERD was predominantly contralateral for unimanual movements and bilateral for bimanual movements. DAR and BSI only changed in healthy controls. Baseline values indicated that DAR was affected by stroke while BSI was affected by both age and stroke. CONCLUSIONS: Bimanual BCI control offers a larger repertoire of movements, while causing the same short-term changes as unimanual BCI-FES. Prolonged practice may be required to achieve a measurable effect on DAR and BSI for stroke. SIGNIFICANCE: Bimanual BCI-FES is feasible in people affected by stroke.

Baseline and therapy-induced chromosome damages in peripheral blood lymphocytes of breast cancer patients assessed by the micronucleus assay.

PURPOSE: Radiotherapy (RT) alone or in combination with chemotherapy (CT) leads nearly always to increase of DNA damage in cancer patients. The purpose of this study was to determine the variability rate and individual sensitivity of breast cancer (BC) patients to the applied RT and RT in combination with CT. METHODS: The analysed sample included 30 women with histologically confirmed BC. The frequency of micronuclei (MN) was estimated in peripheral blood lymphocytes (PBL) by using the cytokinesis-block micronucleus (CBMN) assay before the administered therapy and one month later. RESULTS: The mean therapy-induced MN value was significantly higher (p < 0.001) compared with mean baseline MN. Both therapies (RT and combined RT+CT) significantly increased the MN frequency in patients' lymphocytes (p<0.001), but without significant differences in the therapy-induced MN frequency between these two groups (p > 0.05). The administered therapy induced significant difference in cell kinetics (p < 0.05). The results showed a wide range of inter-individual variability in both baseline and the therapy-induced MN frequency. CONCLUSION: The applied therapies increased the MN frequency in PBL in BC patients, and the presented data indicate absence of synergistic effect of these two therapies. None of the variation factors (age, smoking and therapy type) had influence on the noticed variability.

The effect of combined therapy with ritodrine, erythromycin and verapamil on the frequency of micronuclei in peripheral blood lymphocytes of pregnant women.

The main aim of this study was to investigate the genotoxic effect of combined pharmacotherapy applied in post-operative treatment of cervical cerclage in pregnant women over six days. This study included 19 phenotypically healthy pregnant women in mid-trimester with a diagnosis of cervical insufficiency, mean age 28+/-5.33. The frequency of micronuclei (MN) was estimated in peripheral blood lymphocytes of patients before surgical intervention and after the end of applied pharmacotherapy by application of cytokinesis block micronucleus (CBMN) test. Mean value of baseline MN frequency was 6.84+/-2.91 MN/1000 binucleated cells, and after the end of the applied therapy, 10.32+/-4.27 MN/1000 binucleated cells (P<0.001) were found. The data of cell proliferation index showed that the combined therapy did not induce significant difference in cell kinetics (P>0.05). Our results showed that combined pharmacotherapy treatment over six days significantly increased the frequency of MN in peripheral blood lymphocytes of pregnant women.

Micronucleus frequency in women with genital Chlamydia Trachomatis infection before and after therapy.

The main aim of the present study was to investigate the influence of infection with the intracellular bacterium Chlamydia trachomatis, and subsequent treatments with oral doxycycline or azithromycin on the frequency of micronuclei (MN) in peripheral blood lymphocytes of adult female patients receiving standard doses of these drugs. The frequency of micronuclei was measured in the lymphocytes of 38 newly diagnosed adult women with genital C. trachomatis infection. Samples were taken before and after the therapy, and from 50 healthy control females. The therapy was taken orally during 10 days at 2 x 100 mg per day, and then for another 10 days at 1 x 100 mg per day for doxycycline, and as a single dose of 1g for azithromycin. Isolated lymphocytes from all subjects were cultured by use of the whole-blood method and blocked in metaphase with cytochalasin B (Cyt B). One thousand binucleate cells per subject were scored according to published criteria. The frequency of micronuclei was not significantly higher in samples of infected females before therapy, compared with the baseline frequency in healthy control females (p > 0.05). In patients who received doxycycline, the micronucleus frequency after the end of therapy was significantly higher than before treatment (p < 0.001). The mean frequency of micronuclei in females after the end of the therapy with azithromycin did not show an increase (p > 0.05). The application of linear regression analysis showed that the difference in micronucleus frequency before and after therapy (effect of the antibiotics) was affected by the therapy type. Age and smoking did not affect micronucleus frequency in analyzed samples of patients (p = 0.078, 0.579). We conclude that C. trachomatis infection does not induce micronuclei in peripheral blood lymphocytes of infected adult female patients. Therapy with doxycycline significantly increases the micronucleus frequency in lymphocytes of treated patients, but treatment with azithromycin does not induce micronuclei.

Effect of peptichemio exposure on DNA synthesis in a mammalian cell system in vitro.

The effect of Peptichemio (PTC) on the survival and DNA synthesis in mouse L-cells was studied. Experimental data show that a typical dose-survival curve is obtained when L-cells are cultivated in the presence of PTC. Exposure of L-cells to various concentrations of PTC caused an inhibition in cellular ability to synthesize DNA which is evidenced by the decreased incorporation of 3H-thymidine. This inhibition is dependent on the concentration of PTC and the time of exposure.

[Micronuclei and ageing in a sample of Yugoslavian population]. / Microiadra i starenie. Issledovanie na vyborke zhitelei Iugoslavii.

OBJECTIVE: Instability in the organization and expression of the genetic material has been hypothesized as the basic mechanism of ageing. Aim of this study was to quantify the effect of ageing on spontaneous micronuclei (MN) frequency in peripheral blood lymphocytes. METHOD: Analysis of Yugoslavian population sample (164 tested individuals, age 0-62 years) has performed by application of cytokinesis-block technique (CB). RESULTS: There was an increase of MN frequency with age, from newborns to 40-year-old persons. The total average of MN frequency per 1000 analyzed binuclear cells amounts to 8.03 +/- 0.42, with variation from 0 to 26 MNs. In a sample of 29 newborns the recorded average MN frequency was 6.91 +/- 0.81, while among 69 persons 25-39 years old, the MN frequency was 9.16 +/- 1.00. The lowest average MN frequency, however, was noted in the sample of 34 tested individuals 40 to 62 years of age. CONCLUSION: An increase with age in MN frequency has been observed in samples of studied individuals from newborns to 40-year-old persons. A decrease of MN frequency in older groups could be explained by a gradual decrease of proliferative cell capacities.

In vitro evaluation of the genotoxicity of ritodrine and verapamil in human lymphocytes.

The aim of this study was to investigate the genotoxic effects of ritodrine and verapamil on human peripheral lymphocytes in vitro using micronucleus (MN) test. Also, fluorescence in situ hybridization (FISH) with a centromeric probe was performed to determine the origin of the induced MN. Cells were treated with 8.4 × 10(-6) M - 25.2 × 10(-4) M concentrations for ritodrine and 0.56 - 11 × 10(-5) M concentrations for verapamil, separately and combined. The MN frequencies showed increase after all treatments, but the difference between treated cells and untreated controls were found to be statistically significant only in the concentration range from 8.4 × 10(-5) M - 4.5 × 10(-4) M for ritodrine, 1.1 - 3.3 × 10(-5) M for verapamil, and in combined treatment with concentrations 8.4 × 10(-5) M + 1.1 × 10(-5) M for ritodrine and verapamil. The highest tested concentrations of both medicaments showed cytotoxic effect. Both medicaments decreased the nuclear division index (NDI) in tested concentrations. The results of FISH analysis suggest that verapamil, separately or combined with ritodrine, shows to a larger extent aneugenic than clastogenic effect.

The combined action of X-irradiation, drug and hyperthermia on the DNA in mammalian cells in vitro.

The effects of the alkylating cytostatic drug PTC on the production of radiation-induced single-strand breaks in DNA, and on the repair in L cells incubated at 37 degrees or 42 degrees C were studied. The same amount of SSB is obtained when the cells are treated simultaneously with PTC and hyperthermia as when irradiated with 2 500 rad, but different rate in the rejoining was observed. There is no potentiation of SSB formation by pretreatment of cells with 10 microgram PTC/ml for 2 hours at 42 degrees C before irradiation, but in these cells less effective repair occurs. The effect of PTC on the rejoining of SSB induced with 2 500 rad depends on the drug's concentration and post-incubation time.

Effects of hyperthermia and drug in cultured mammalian cells.

Hyperthermia (42 degrees C) and peptichemio (PTC) applied simultaneously result in an increased killing effect and in a significant induction of single strand breaks (SSB) of DNA molecule. The enhanced killing effect was observed in all circumstances, whenever hyperthermia was applied before, during or after PTC treatment, but the most effective cell killing was obtained when hyperthermia and PTC were applied simultaneously. The results show that PTC concentrations used in these experiments do not induce SSB in DNA molecule during incubation for 2 hours at 37 degrees C. When the cells were exposed to PTC and hyperthermia the induction of SSB was observed. The number of SSB depends on the exposure time and PTC concentration. Cells with a greater number of SSB lost the capacity for repair during post-incubation at 42 degrees C.