Ischaemic brain changes associated with catheter-based diagnostic cerebral angiography : a diffusion-weighted imaging study

Purpose: This study aims to evaluate the incidence of clinically silent embolic cerebral infarctions and associated risk factors following diagnostic cerebral angiography with diffusion-weighted imaging (DWI). Material and methods: A total of 71 cerebral digital subtraction angiograms (42 male, 29 female, average age: 56.0 ± 15.0) obtained using nonionic contrast material were prospectively evaluated. To assess embolic events, before and after (1-3 days) angiography, DWI was performed. The risk factors for embolic ischemic brain changes such as the patient's age and sex, atherosclerotic vessel wall disease, type of indication for catheter angiography, the number and size of the catheters, anatomic variants, selective/nonselective catheterization, contrast media volume, and time of procedure were determined. Fisher's exact tests and Student t-tests were used for the statistical analyses of outcomes. Results: Thirteen new silent ischemic lesions were identified in 7 out of 71 patients who underwent diagnostic cerebral angiography. Embolic cerebral lesions were often 6-10mm in diameter. According to the findings in this study, there was a strong correlation between diffusion abnormality and patient age, which was considered risk factors (p 0.05). Conclusions: In elderly patients, the angiographic procedures should be performed meticulously and DWI in all patients obtained routinely, even if the regular neurological examination shows they are healthy. In this way, the presence of microemboli and clinical results can be evaluated

Micronucleus evaluation in mitogen-stimulated lymphocytes of PUVA treated patients

PUVA describes the treatment of patients with psoralens plus an exposure to a source of UV light of 320-400 nm (UVA). Contradictory results have been reported on the chromosomal damage of PUVA when assayed by sister chromatid exchange (SCE) method. Micronucleus (MN) test is used to detect both clastogenic (breaking) and aneugenic (abnormal segregation) effect of physical/chemical agents on the chromosomes. No data have been found on the MN formation in the cells of PUVA treated patients. Frequency of micronuclei in 72 hours cultivated/mitogen-stimulated lymphocytes of patients have been evaluated at zero time and after 20, 40, 60 sessions of PUVA treatment. While the beginning MN frequency was similar to0.22% (n = 23), it raised to similar to0.32 (n = 23), similar to0.42 (n = 14) and similar to0.53% (n - 10) corresponding respectively to 20, 40 and 60 sessions. These sessions correspond reciprocally to 54+/-23, 172+/-48, 300+/-61 joules/cm(2) of UVA and 13, 26, 39 mg/kg of 8-metoxypsoralen (8-MOP). While large interindividual. variances were apparent, highly significant differences have been observed between initial MN frequency and after that of the 20, 40 and 60 sessions, (p = 0.000, p = 0.004, p = 0.005, reciprocally, Wilcoxon two-related samples test). The coefficient of correlation between MN frequency and UVA doses starting from zero to 60 sessions of treatment has been found as r = 0.61. This indicates a significant relationship between UVA doses and MN frequencies. However, MN inducibility and synergistic property of 8-MOP with UVA should be taken into account. Gradual MN increase during different sessions of PUVA treatment shows that -once appeared-, a part of MN at least persist in the cells of patients from a few days to a few weeks. Smoking as a confounding factor seems to increase MN frequency (p = 0.053, Mann-Whitney U-test) in the beginning population, taken as the control population. This is the first report on the kinetics of MN formation during different sessions of PUVA treatment. Based on our results, we concluded that PUVA treatment causes a detectable chromosome damaging effect on the relatively profound cells/tissues of its human users. Therapists should be careful with its use, especially on the patients who may be more susceptible to carcinogenesis (e.g. immunosuppressed and/or elderly subjects)

Increased micronucleus frequency after oral administration of cadmium in dogs

Cadmium (Cd) is a toxic heavy metal that has been classified as a human carcinogen by the International Agency for Research on Cancer. The genotoxic effects of cadmium oxide (CdO) were investigated in cultured dog lymphocytes after a short-term oral CdO administration by the micronucleus (MN) test. The dogs were given 10 mg CdO/kg body weight per day for 3 and 28 d, respectively group I (n = 7) and group II (n = 6). Blood samples were collected at the beginning of feeding and at 4 and 29 d after Cd administration and cultured for 72 h. Whereas no significant increase in the MN frequency in group I was observed (p = 0.398), a significant MN induction with CdO was found in group II (p = 0.028) when compared with initial MN frequencies of dogs in both groups. Our results suggest that CdO might be directly and/or indirectly genotoxic after a monthly oral administration of CdO in dogs

Essay on the nucleoli survey by the alpha- and beta-satellite DNA probes of the acrocentric chromosomes in mitogen-stimulated human lymphocytes

The two constitutive heterochromatin (alpha- and beta-satellite DNA) probes of human acrocentric chromosomes were essayed separately to label the nucleoli in the phytohemagglutinin (PHA)-stimulated human lymphocytes. Fluorescent in situ hybridisation (FISH) results have shown that: a) whole (100 %) signal-nucleoli overlapping was obtained with both heterochromatin probes in maximally activated nuclei (MANs); b) partial overlapping was observed in non activated or slightly activated nuclei; c) random signal-nucleolus overlapping (background level) was found to be similar to 6 % by the NOR-irrelevant euchromatic probe (D5S23); d) Yq-nucleolus association in the MANs was found to be similar to 97 % without the subtraction, of the background level. We concluded that: a) acrocentric alpha- or beta-satellite DNA probes may be used as nucleolar markers only in the MANs and not in slightly activated or non-activated nuclei; b) the distances between rDNA loci and alpha-/beta-satellite DNA on human acrocentrics are short enough to permit their observation on the same nucleolus. (C) 2000 Editions scientifiques et medicales Elsevier SAS

Condensed chromatin surface and NORs surface enhancement in mitogen-stimulated lymphocytes of Down syndrome patients

Mitogen-stimulated lymphocytes of 20 Down syndrome (DS) patients with regular trisomy 21 contain more condensed chromatin surface (11.28 +/- 2.64% of the total nuclear surface: mean SD) and more nucleolus organiser regions surface (13.21 +/- 3.45 %) than that of 12 healthy controls: (8.84 +/- 2.23 and 9.12 +/- 2.33 %, reciprocally). The source of this peculiarity has been investigated. A computer program was designed for the planimetric measurement of the condensed chromatin surface (CCs)/ total nuclear surface(TNs) and the nucleolus organiser regions surface (NORss) /TNs proportions in interphase nuclei. CCs/TNs and NORss/TNs of 100 maximally activated nuclei (MANS) were measured for each patient and control case. The difference was found highly significant (P < 0.01). Nuclei with a diameter of greater than or equal to 17 mum measured on the slide (in flattened state) were considered as maximally activated nuclei (MANS). NORss/TNs enhancement and fluorescent in situ hybridisation (FISH) studies in MANS of DS patients indicate that this phenomenon is due to the over-expression (or lack of downregulative mechanism) of NORs (rDNA) to some extent, including the NOR of the supernumerary chromosome 21. No statistical difference was observed between 12 healthy controls and 5 Robertsonian translocation type of DS Patients (where the two involved NORs are missing) when the two parameters were considered. (C) 2001 Editions scientifiques et medicales Elsevier SAS