Postnatal exposure to N-ethyl-N-nitrosurea disrupts the subventricular zone in adult rodents.

N-ethyl-N-nitrosurea (ENU), a type of N-nitrous compound (NOC), has been used as inductor for brain tumours due to its mutagenic effect on the rodent embryo. ENU also affected adult neurogenesis when administered during pregnancy. However, no studies have investigated the effect of ENU when exposured during adulthood. For this purpose, three experimental groups of adult mice were injected with ENU at different doses and killed shortly after exposure. When administered in adult mice, ENU did not form brain tumours but led to a disruption of the subventricular zone (SVZ), an adult neurogenic region. Analyses of the samples revealed a reduction in the numbers of neural progenitors compared with control animals, and morphological changes in ependymal cells. A significant decrease in proliferation was tested in vivo with 5-bromo-2-deoxyuridine administration and confirmed in vitro with a neurosphere assay. Cell death, assessed as active-caspase-3 reactivity, was more prominent in treated animals and cell death-related populations increased in parallel. Two additional groups were maintained for 45 and 120 days after five doses of ENU to study the potential regeneration of the SVZ, but only partial recovery was detected. In conclusion, exposure to ENU alters the organization of the SVZ and causes partial exhaustion of the neurogenic niche. The functional repercussion of these changes remains unknown, but exposure to NOCs implies a potential risk that needs further evaluation.

[One center's experience of coronary angioplasty with a 5 French catheter guide by a femoral approach at the same time as coronary angiography]. / Expérience monocentrique de l'angioplastie coronaire par cathéter guide 5 French menée par voie fémorale dans le même temps que l'examen coronarographique.

The object of this study was to assess the feasibility of so-called ad hoc 5 F percutaneous transluminal coronary angioplasty (PTCA). This monocentric register included 200 consecutive procedures (233 lesions) of 5F PTCA by a femoral approach after a bolus of standard heparin (50 to 70 IU/kg). The population included 15.4% of stable angina, 29.4% of unstable angina, 11% acute phase, 13.5% post-revascularisation angina and 30.7% post-infarction cases. A successful procedure was defined as a good angiographic result without ischaemic complications. A failed 5F procedure was defined by the need to fall back on a 6F PTCA. The peripheral vascular complications were recorded. The lesions were stented in 77.4% of cases including 13.4% of direct stenting. There were 200 successful procedures (87%). The failures (N = 26) were mainly explained by the inability to cross chronic obstruction (N = 11). The ischaemic complications included 2 coronary bypasses (2 retrograde dissections of the left anterior descending artery) and 7 enzymatic increases without ECG changes. Fall back to 6F PTCA was required in 4 cases (1.7%) always because of the instability of the 5F catheter guide before the procedure. The quality of coronary contrast was estimated to be good. The vascular complication rate was low with 2% of communicating haematomas (N = 4). Therefore, 5F PTCA is feasible with failure and complication rates comparable to those reported with catheters of larger dimensions. One of its principal advantages is "ad hoc" angioplasty after 5F coronary angiography.