Endovascular treatment of cerebral aneurysms in relation to their parent artery wall: a single center study.

We report our two-year experience in the endovascular treatment of brain aneurysms in relation to their parent artery wall. We prospectively recorded patients with intracranial aneurysms (107 ruptured - 38 unruptured) treated with coiling during a two-year period: 145 patients, 94 females and 51 males - mean age 56 years. The aneurysms were divided into side-wall (A) and bifurcation (B) groups. A total occlusion rate was noted in post-embolization angiograms in 101 aneurysms (70%) with a morbidity of 4%. No angiographic recurrence arose in the six-month follow-up. The two groups had a similar total occlusion rate (68.31% and 71.8% respectively), while the complication rate was 3% in group A and 4.7% in group B. Significant differences between the two groups were noted in the number of assisted coiling cases: 28 out of 60 cases (46.7%) in group A - 14 out of 85 cases (16.5%) in group B. Further statistical analysis showed strong dependencies for the type of endovascular procedure between the ruptured and unruptured aneurysms in both groups (p 0.000<0.05), but no dependencies between the aneurysm occlusion rate and the ruptured or non-ruptured aneurysms, or between the occlusion rate and the type of endovascular procedure (p 0.552>0.05 and 0.071>0.05 respectively). In conclusion, the anatomic relation of the aneurysm sac with the wall of the parent artery is important, as significant differences in endovascular practice, devices and techniques were noted between side-wall and bifurcation aneurysms.

Nurses' training and confidence on deep venous catheterization.

AIMS: The rough estimation of the education and the self-confidence of nurses, both students and professionals, regarding deep venous catheterization in adult patients, the evaluation of the change in self-confidence of one team of students who were trained with a simulator on deep venous catheterization and the correlation of their self-confidence with their performance recorded by the simulator. MATERIAL AND METHODS: Seventy-six nurses and one hundred twenty-four undergraduate students participated in the study. Fourty-four University students took part in a two-day educational seminar and were trained on subclavian and femoral vein paracentesis with a simulator and an anatomical model. Three questionnaires were filled in by the participants: one from nurses, one from students of Technological institutions, while the University students filled in the previous questionnaire before their attendance of the seminar, and another questionnaire after having attended it. RESULTS/DISCUSSION: Impressive results in improving the participants' self-confidence were recorded. However, the weak correlation of their self-confidence with the score automatically provided by the simulator after each user's training obligates us to be particularly cautious about the ability of the users to repeat the action successfully in a clinical environment. CONCLUSION: Educational courses and simulators are useful educational tools that are likely to shorten but in no case can efface the early phase of the learning curve in clinical setting, substituting the clinical training of inexperienced users.

Effect of polarized light in the healing process of pressure ulcers.

A trial was conducted to examine the effect of polarized light on pressure ulcers of 1st, 2nd and 3rd grades. Patients with two pressure ulcers, one of which received the polarized light therapy (experimental ulcer) and the other acting as control, were included in the study. The experimental ulcers received treatments for 2 weeks consisting a 5 min therapy session each day, excluding weekends, for 10 days. Experimental and control ulcers were assessed as they appeared on admission and reassessed at the end of each week. Fifty-five patients aged 37-85 years (67.1 +/- 11.9 years) were studied. Pressure ulcers of 1st, 2nd and 3rd grades receiving extra treatment with polarized light had increased values of epithelial tissue between the first and second assessments of 0-30.9% and between the second and third assessments of 30.9-21.7%. Values of the control pressure ulcers were, respectively, from 0 to 5.5% and from 5.5% to 3.1%. The mean pink/white colour values of the experimental ulcers, between the first and second measurements increased significantly compared with the control ulcers (P = 0.021) and also increased significantly between the second and third measurements (P = 0.003). The mean values of 'no and minimal exudate' of the experimental ulcers increased significantly between first and second measurements compared with the control ulcers (P = 0.001), and similarly, significantly between the second and third measurements (P = 0.002). Mean surface areas of the experimental ulcers decreased significantly between the first and second measurements from 2.84 to 2.54 cm2 (P < or = 0.001) and between the first and third measurements from 2.84 to 2.26 cm2 (P < or = 0.001). Mean surface areas of the control ulcers decreased between the first and second measurements from 2.10 to 2.08 cm2 (P < or = 0.42) and between the first and third measurements from 2.10 to 2.04 cm2 (P < or = 0.007). Pressure ulcers subjected to extra treatment with polarized light in the early stages (first to third measurements) showed improvement in the healing process than the control ulcers.

Protooncogene c-fos Involvement in the Molecular Mechanism of Rat Brain Sexual Differentiation.

Brain sexual differentiation is mediated through testosterone, which acts during the perinatal period in the form of both 5alpha-dihydrotestosterone and estradiol. In order to gain insight into the molecular mechanisms involved, we studied induction of c-fos, an index of functional neuronal activation, in the 2-day-old female rat brain after injection of a masculinizing dose of testosterone. Administration of testosterone resulted in induction of c-fos gene expression in the hypothalamus, as determined by Northern analysis. Following immunocytochemistry, we demonstrated an increase in the number of Fos-positive nuclei in the median and medial preoptic nucleus, the medial preoptic area extending to the lateral preoptic area, and the peri- and paraventricular area. In an effort to see whether testosterone acted as 5alpha-dihydrotestosterone or as estradiol, we injected either steroid and looked at fos induction. Estradiol mimicked the effect of testosterone, while 5alpha-dihydrotestosterone was without effect. Furthermore, injection of an estrogen receptor blocker, clomiphene, together with testosterone, abolished the testosterone-induced increase in Fos-positive nuclei, thus confirming the finding that testosterone induces c-fos by acting through estrogen receptors. Electrophoretic mobility shift assays showed that nuclear extracts from 2-day-old female hypothalamus contain a protein, most probably the estrogen receptor, which binds specifically to oligodeoxynucleotides with the sequence of either vitERE, the consensus estrogen-responsive element (ERE) found in the vittelogenin gene, or fosERE, the ERE found in the 3'-untranslated region of the mouse c-fos gene. This suggests that the effect of testosterone-derived estradiol on c-fos expression is a direct one, mediated by binding of estrogen receptors to an ERE in the c-fos gene-regulatory regions.

NMDA receptor mediated changes in IGF-II gene expression in the rat brain after injury and the possible role of nitric oxide.

This study was undertaken in order to investigate the role of insulin-like growth factor (IGF)-II, c-fos, N-methyl-D-aspartate (NMDA) receptors, and nNOS in the cellular processes following a penetrating brain injury. IGF-II mRNA levels, as determined by Northern analysis, were decreased at 4, 8, and 24 h after brain injury, in the lesioned, compared to the contralateral intact hemisphere. Forty-eight and 72 h after the injury, there was no difference between the lesioned and the contralateral intact hemisphere in IGF-II mRNA levels. c-fos mRNA levels followed a parallel, but opposite course: They were increased at 4, 8 and 24 h after the injury, while at 48 and 72 h c-fos mRNA levels in the lesioned hemisphere did not differ from those in the intact. Administration of MK-801 reversed the injury-induced decrease in IGF-II mRNA levels. Administration of MK-801 resulted in an increase in IGF-II mRNA in both the intact and the lesioned hemispheres. Brain injury resulted in an increase in nNOS immunopositive cells in the hippocampal formation, which was detectable at 4 and 12, but not 48 h after the injury. These results suggest that IGF-II, c-fos, NMDA receptors and nNOS are involved in the cellular responses to brain injury.

Immunocytochemical localization of glycogen phosphorylase kinase in rat brain sections and in glial and neuronal primary cultures.

The physiological function of brain glycogen and the role of phosphorylase kinase as a regulatory enzyme in the cascade of reactions associated with glycogenolysis in the brain have not been fully elucidated. As a first step toward elucidating such a function, we studied the localization of phosphorylase kinase in glial and neuronal primary cell cultures, and in adult rat brain slices, using a rabbit polyclonal antibody against skeletal muscle glycogen phosphorylase kinase. Immunocytochemical examination of rat astroglia-rich primary cultures revealed that a large number of cells were positive for glycogen phosphorylase kinase immunoreactivity. These cells were also positive for vimentin, a marker for immature glia, while they were negative for glial fibrillary acidic protein, a marker for mature astroglia, and for galactocerebroside, an oligodendroglial marker. Neurons in rat neuron-rich primary cultures did not show any kinase-positive staining. In paraformaldehyde-fixed adult rat brain sections, phosphorylase kinase immunoreactivity was detected in glial-like cells throughout the brain, with relatively high staining found in the cerebral cortex, the cerebellum, and the medulla oblongata. Phosphorylase kinase immunoreactivity could not be detected in neurons, with the exception of a group of large neurons in the brain stem, most likely belonging to the mesencephalic trigeminal nucleus. Phosphorylase kinase was also localized in the choroid plexus and to a lesser degree in the ependymal cells lining the ventricles. Phosphorylase kinase thus appears to have the same cellular distribution in nervous tissue as its substrates, i.e. glycogen phosphorylase and glycogen, which suggests that the physiological role of brain phosphorylase kinase is the mobilization of glycogen stores to fuel the increased metabolic demands of neurons and astrocytes.