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In our rapidly evolving world, neuroradiology already has a past and a palpable story. The first neuroradiologic examinations were invasive and date back to the early 20th century. The first Symposium Neuroradiologicum was organized 79 years ago. Since then, neuroradiology has progressed with

The routine use of exclusion angiography in trauma to the extremities has resulted in varying percentages of negative studies, mostly because of a great variability in location and type of injury. The authors reviewed 117 low-velocity gunshot wounds to the extremities. Twenty-six cases presented with hard signs of vascular injury and underwent immediate exploration. Ninety-one exclusion angiograms were performed (11 for soft signs and 80 for proximity only), 89 (98%) were considered negative. Two cases (2 % ) that presented without hard signs required vascular repair. Physical examination alone was 93 % sensitive and 99 % specific for recognition of vascular injuries. Routine angiography did not substantially improve the diagnostic accuracy and had a positive predictive value of only 2%. The authors conclude that angiography may be safely omitted in low-velocity gunshot wounds to the extremities if the absence of signs or symptoms of vascular injury can be firmly established.

Most urologists treating stone disease with any method (ESWL, PCL, URS) have encountered problems of poor stone visualization with fluoroscopy. This difficulty to localize urinary tract (UT) stones or fragments may result in incomplete stone extraction, prolonged surgery and increased risk of recurrence and post-operative complications. We have sought and found means to increase the radioopacity of mineral UT stones by a simple pre-operative perfusion technique. The capacity of radioopacification has first been demonstrated in in vitro incubations of fragments of human mineral stones with aqueous solutions of barium, of the lanthanides and of the two natural actinides. Most of the incubations led to considerable radio-contrast enhancement and heavy metal incorporation, measured by X-ray fluorescence analysis. Dogs with implanted human stone fragments were used as an in vivo model. The UT were perfused through a retrograde pyelic catheter with heavy metal salts solutions, the ensuing radioopacification of the implanted UT-stones was estimated by abdominal radiographies and the metal incorporation was measured on the retrieved stones. Considerable radioopacity enhancement together with heavy metal incorporation was observed for the following elements: Sr, Ba and the lanthanides Gd and Yb. The pathological evaluation of the urothelial linings from animals treated with lanthanide salt showed no toxic effects.

To study prognostic factors of obliteration and risk factors of brain radiation necrosis in order to propose an algorithm for radiosurgery prescription for cerebral arteriovenous malformations (cAVM).One hundred and seventy-nine patients were analysed. Radiosurgery delivered 6 or 10 MV X-rays by arc therapy in 84% of cases, or by fixed field in 16% of cases using two different micro-multileaf collimators (micro-MLC). Follow-up consisted of screening radiation necrosis by MRI every 6 months, and assessing local control by arteriography every 2 years. Obliteration was defined as at least 95% reduction of cAVM volume. Cox proportional hazard model was used to evaluate the local control and the appearance of radiation necrosis over time.Local control rate was 82.7% with the mean follow-up of 3.1 years (0.5-11). Significant prognostic factors were: simple nidus (RR=2.8, p0.0001), number of embolizations before radiosurgery below 4 (RR=2.9, p0.0001), prescribed dose to the periphery of at least 18 Gy (RR=2, p=0.0002), nidus volume below8cm(3) (RR=1.9, p=0.0002), and number of table positions below six (RR=1.4, p=0.05). Radiation necrosis rate was 11.2% with a mean time to onset of 18 months. Significant predictive factors were: fixed field versus arc therapy (according to MLC RR=9.1, p0.0001, and RR=15.1, p=0.01), age below 30 years (RR=2.5, p=0.04), depth of cAVM greater than or equal to 7 cm (RR=7.6, p=0.008), and volume of brain tissue covered by the 12 Gy isodose (V12 Gy) of at least 11 cm(3) (RR=7.8, p=0.05).A radiosurgery prescription algorithm taking into account the prescribed dose to the periphery (or = 18 Gy) and reduction of V12 Gy was elaborated from these data.

The lack of consensus in the management of unruptured intracranial aneurysms (UIA) has resulted in a variety of different clinical practices. The aim of this study is to analyze these different practices.A questionnaire concerning the management of UIA was mailed out to French neurosurgeons (NS) and neuroradiologists (NR). Eighteen responses from 17 teams of NS and 23 responses from 19 teams of NR were included in our analysis.In making a therapeutic decision, about three-quarters of both NR and NS take into account the age of the patient and all of our responders except one consider the aneurysm's morphology, especially its size and neck structure. Pinpointing the location of the aneurysm is an important factor for 61% of NR and 40% of NS. Information concerning the risk of aneurysm rupture and the risks of treatment is routinely given to the patient orally and, sometimes, in writing. The follow-up of UIA treated by NR usually consists of one X-ray angiography and several MR angiographic (MRA) films taken over a period of at least five years and, sometimes, for the rest of the patient's life (22%). The follow-up after surgical treatment mainly comprises X-ray angiography for a limited period of time-usually from five to ten years. The follow-up of untreated aneurysms is usually by either MRA or angioCT. For most NR, the duration of follow-up is long and, sometimes, unlimited. For NS, the duration is more difficult to pinpoint: the response was indeterminate in 28 and 33% gave no response at all. If the first screening tests negative, 44% of NS and 61% of NR propose a repeat screening.Given the differences in the management of UIA as revealed by this survey, a multidisciplinary approach that combines the various clinical practices may be the best way forward.

Pheochromocytomas are catecholamine-producing tumors of the adult adrenal medulla. They are rare in humans and most other species but common in laboratory rats. However, the relevance of rat pheochromocytomas as a model for their human counterparts is uncertain. Previous studies of spontaneous and drug-induced rat pheochromocytomas and the PC12 pheochromocytoma cell line suggested a distinctive noradrenergic phenotype, possibly reflecting origin from a progenitor not present in the adult human adrenal. In this study, we studied 31 pheochromocytomas derived from test and control male and female rats in toxicologic studies for expression of the epinephrine-synthesizing enzyme phenylethanolamine-N-methyltransferase (PNMT) and the receptor tyrosine kinase Ret. PNMT, which defines adrenergic chromaffin cells, is frequently expressed in human pheochromocytomas, often in tumors that also overexpress RET. We also tested for the expression of the cell cycle checkpoint protein p27(Kip1), which recently was reported absent in pheochromocytomas from a strain of rats with a hereditary mixed multiple endocrine neoplasia (MEN)-like syndrome. Using immunoblots, we demonstrated PNMT expression in almost 50% of the 31 tumors, although often at lower levels than in normal rat adrenal medulla. The majority of tumors overexpressed Ret. There was no apparent correlation between PNMT and Ret. However, in this study, PNMT expression was strongly associated with tumors arising in female rats, while overexpression of Ret did not show a sex predilection. Robust expression of p27(Kip1) was seen in all tumors from the toxicologic studies and also in a small sample of pheochromocytomas from Long-Evans rats, which were reported to have a mixed MEN-like syndrome in the 1980s. The present results show that rat pheochromocytomas have greater phenotypic diversity than previously believed and greater similarity to their human counterparts with respect to these two important markers. Loss of p27(Kip1) does not appear to account for the high frequency of pheochromocytomas in commonly utilized rat strains.

Bovine inner cell masses (ICMs) were isolated by immunosurgery at day 8 or 10, or by dissection at day 14, and combined with day-5.5 morulae. Aggregation was obtained between 89%, 62%, and 0% of the day-5:day-8, day-5:day-10, day-5:day-14 composites, respectively. Chromosome analysis of composites, respectively. Chromosome analysis of composites potentially carrying the 1/29 translocation as a chromosome marker and temporarily transferred to the bovine uterus for 8 days showed that chimaeric day-14 embryos can be obtained from day-5:day-8 aggregation. The definitive transfer of eight day-5:day-8 and 11 day-5:day-10 composites resulted in the birth of six and four calves, respectively; five of the six, but none of the four, were chimaeric. The five chimaeras showed mostly the ICM phenotype. The morphological differences between ICMs at different stages of development were examined by electron microscopy and related to the success of the aggregation technique. It is concluded that bovine embryonic cells can regulate for at least 3 days difference in development but not 5 days even though aggregation is still possible.

Targeting surface receptors overexpressed on cancer cells is one way to specifically treat cancer versus normal cells. Vintafolide (EC145), which consists of folate linked to a cytotoxic small molecule, desacetylvinblastine hydrazide (DAVLBH), takes advantage of the overexpression of folate receptor (FR) on cancer cells. Once bound to FR, vintafolide enters the cell by endocytosis, and the reducing environment of the endosome cleaves the linker, releasing DAVLBH to destabilize microtubules. Vintafolide has shown efficacy and improved tolerability compared to DAVLBH in FR-positive preclinical models. As the first FR-targeting drug to reach the clinic, vintafolide has achieved favorable responses in Phase II clinical trials in FR-positive ovarian and lung cancer. However, some FR-positive patients in these clinical trials do not respond to vintafolide. We sought to identify potential biomarkers of resistance to aid in the future development of this and other FR-targeting drugs. Here, we confirm in both in vitro and in vivo preclinical models that high P-glycoprotein (P-gp) expression was the strongest predictor of resistance to DAVLBH in a panel of 359 cancer cell lines. Furthermore, targeted delivery of DAVLBH via the FR as in vintafolide fails to overcome P-gp mediated efflux of DAVLBH as seen in FR-expressing engineered cell lines and in vivo models. Therefore, we suggest that patients whose tumors express high levels of P-gp be excluded from future clinical trials for vintafolide as well as other FR-targeted therapeutics bearing a P-gp substrate. Citation Format: Amy D. Guertin, Jennifer O'Neil, Alexander Stoeck, Joseph A. Reddy, Razvan Cristescu, Brian B. Haines, Marlene C. Hinton, Ryan Dorton, Alicia Bloomfield, Melissa Nelson, Marilynn Vetzel, Serguei Lejnine, Michael Nebozhyn, Theresa Zhang, Andrey Loboda, Kristen L. Picard, Emmett V. Schmidt, Isabelle Dussault, Christopher P. Leamon. High levels of expression of P-glycoprotein/multidrug resistance protein result in resistance to vintafolide. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B65.

We report the MR imaging findings in a 20 year old woman with status epilepticus of more than 3 months duration following an episode of lymphocytic meningitis. Repeated MR examinations showed progressive symmetrical cortical lesions, followed by subcortical and basal ganglia lesions which evolved to cortical laminar necrosis and hemorrhagic necrosis with eventual subcortical cerebral atrophy. This case has similarities with animal status epilepticus models. Biological investigations were all negative. This suggests that the brain lesions may be related to the prolonged status epilepticus.

This paper deals with the modeling of a vascular C-arm to generate 3D augmented fluoroscopic images in an interventional radiology context. A methodology based on the use of a multi-image calibration is proposed to assess the physical behavior of the C-arm. From the knowledge of the main characteristics of the C-arm, realistic models of the acquisition geometry are proposed. Their accuracy was evaluated and experiments showed that the C-arm geometry can be predicted with a mean 2D reprojection error of 0.5 mm. The interest of 3D augmented fluoroscopy is also assessed on a clinical case.

with the working group composed of: S. Bracard, J. Byrne, L. Feng, O. Flodmark, A. Goulao, M. Leonardi, M. Mawad, J. Mishra, J. Moret, M. Negoro, R. Piske, B. Richling, G. Rodesch, J. Ruscalleda, K. terBrugge, A.Valavanis.

Medical risk management has one main purpose: to ensure the safety of care. The law of March 2002 has generated a true cultural revolution. The radiologist is involved with new and difficult areas of medical liability due to technical advances, the increasing number of imaging techniques, the increasing complexity of imaging techniques, their efficiency and the need for multidisciplinary approach. Imaging recommendations requiring increasing levels of technical and clinical skills. The radiologist is liable with regards to the indications of imaging studies, and also with regards to informed consent. The prevention of medicolegal problems is achieved by competency, which must be combined to good liability insurance and ongoing vigilance supported by appropriate continuous medical education.

Intra spinal primary melanoma is a rare entity. We report a new case, atypical in relation to its primary radicular location, and to its early metastatic intradural and extra-medullary location, six months later. MRI is the more valuable examination, showing a spontaneously hyper-intense lesion on T1-weighted MR images, intense enhancement after gadolinium administration, and decreased signal on T2-weighted MR images, thus suggesting a diagnosis of melanocytic or hemorrhagic lesion. Signal abnormalities are not specific and definitive diagnosis is established after histological analysis.

Naturally, neuroimaging emergencies are a component of the global subject of emergencies that have for several years been a frequent subject in the press. The current situation is the consequence of the evolution of ideas from contractual liability to the frequently discussed principle of precaution. Examples offered by the daily practice allow to emphasize the main difficulties: diagnosis of headaches, seizure episode on public roads, head trauma, stroke... The medical liability of the neuroradiologist is not the same for diagnostic or interventional neuroradiology; it can sometimes be shared with other physicians. This liability includes the indication, the quality of the diagnosis, the information of the patient and relatives, the communication of results with other physicians, the maintenance of the equipment... Knowledge of potential pitfalls allows preventive measures including competence of the neuroradiologist, informed patient consent, and written precise protocols are the most important. However, according to the evolution of our societies, it is likely that it will become increasingly difficult to achieve a professional neuroradiology career without being questioned; it is thus advisable to be prepared for such eventuality.

La neuroradiologie interventionnelle est historiquement la plus ancienne des hyperspecialites de radiologie interventionnelle. Ceci est du au fait que le systeme nerveux — et notamment le cerveau — est une structure a la fois fragile et hautement fonctionnelle; en consequence, tout acte neurochirurgical s'adressant a une structure profonde risque d'entrainer de lourdes sequelles, du seul fait de la voie d'abord et de l'approche necessaire au traitement.

To investigate factors predisposing to spontaneous hemorrhage in the early period after embolization of brain arteriovenous malformations (AVMs).The authors report 15 cases of spontaneous hemorrhage in a consecutive series of 492 brain AVMs totally or partially treated with intranidal injections of a polymerizing mixture, from 1984 to June 1998. Retrospective analysis of the records was performed with special attention to the angio-architectural features before embolization, details of embolization procedures and induced angiographic modifications.Pre-embolization features of greater incidence were the presence of steal phenomena (87%), multiple feeding arteries (100%), a compact aspect of the nidus (93%), and lobar topography (87%). In most cases the volume of injected glue exceeded 1 ml (80%), venous embolization was significant (67%) and immediate angiographic control showed venous stagnation in and/or around the nidus (80%). Four patients were asymptomatic (incidental discovery on systematic CT at day 3). Among the remaining 11 symptomatic patients, 6 were operated to evacuate an intracerebral hematoma, outcome was good for 4, 5 were left with sequelae and 2 died.Spontaneous hemorrhagic complications affected 3.04% of embolized patients. The combination of certain angio-architectural features, significant venous embolization and persistent venous stagnation within the nidus seem to have some predictive value of high risk hemorrhage. In light of this, additional preventive measures must be taken and a neurosurgical team systematically kept on standby.

Vintafolide (also known as EC145 or MK-8109), is a small molecule drug conjugate for the treatment of cancers expressing high affinity folate receptor (FR). Vintafolide consists of the anti-mitotic vinca alkaloid desacetylvinblastine monohydrazide (DAVLBH) chemically linked to folic acid. Binding of vintafolide to FR located on the cell surface delivers the chemotherapy payload directly to the tumor cell. Clinical investigations of vintafolide are underway in ovarian and lung cancer, indications with a high prevalence of FR expression. Triple negative breast cancer (TNBC) may represent an additional indication for vintafolide due to the prevalence of FR expression (∼30%), sensitivity to vinca alkaloids, and unmet medical need. Vintafolide and/or DAVLBH were evaluated in preclinical models of TNBC as monotherapies and in combination with taxanes (paclitaxel or docetaxel). Taxanes represent a commonly used standard of care therapy for TNBC. A panel of TNBC cell lines was generally sensitive to DAVLBH, with IC50s ranging from 4-67 nM. In the majority of cell lines tested, DAVLBH in combination with paclitaxel provided combination benefit and induced more cell death than either single agent. Vintafolide and DAVLBH were further evaluated in vivo in the FR-high MDA-MB-231 and FR-low CAL51 TNBC xenograft models. Vintafolide was dosed at its MTD of 9.6 mg/kg three times per week (TIW), and at 1.5 mg/kg TIW. DAVLBH was dosed at its MTD of 0.77 mg/kg TIW. Mice were dosed for 3 weeks followed by a 6 week follow-up. Both vintafolide doses resulted in marked MDA-MB-231 tumor regressions of 56-78% at the end of therapy (Day 21) and 75% cures (6 of 8 mice) over the 6 week follow-up period. In the CAL51 model, vintafolide produced 8% and 76% tumor growth inhibition (TGI), respectively, at the 1.5 and 9.6 mg/kg doses, and no cures. DAVLBH was less efficacious compared to vintafolide, giving 96% TGI in the MDA-MB-231 model and 46% TGI in the CAL51 model. In mechanism of action studies in the MDA-MB-231 xenograft model, a dose of vintafolide that gave tumor regressions/cures was associated with increased phospho-histone H3 staining, indicative of a mitotic block of tumor cells, and consistent with the mechanism of action of vinca alkaloids. In combination therapy experiments in vivo, docetaxel (20 mg/kg weekly) monotherapy achieved near tumor stasis (98% TGI) of MDA-MB-231 tumors over 3 weeks of therapy, but all tumors re-grew upon cessation of treatment. Since vintafolide monotherapy at 1.5 mg/kg TIW gave significant regressions and cures, a combination benefit with docetaxel could not be determined. However, DAVLBH and docetaxel combination therapy delayed tumor re-growth over single agents upon follow-up, suggesting benefit of a vinca alkaloid / taxane combination. Taken together, these preclinical data support further investigation of vintafolide monotherapy and in combination with taxane therapy in TNBC. Citation Format: Brian B. Haines, Jennifer O'Neil, Marlene C. Hinton, Christopher Ware, Tammie C. Yeh, Tianxiao Sun, Kristen L. Picard, Theresa Zhang, Emmett V. Schmidt, Isabelle Dussault. Preclinical activity of Vintafolide/MK-8109 monotherapy and in combination with standard of care therapy in triple-negative breast cancer models. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1677. doi:10.1158/1538-7445.AM2014-1677

Objectif Listeria Monocytogenes est un germe classique de meningite neonatale. Le diagnostic est possible au-dela de cette tranche d’âge, mais s’avere plus delicat. Sujet Un nourrisson de 15 mois est hospitalise pour syndrome meninge. La ponction lombaire (PL) montre un liquide trouble a predominance de polynucleaires neutrophiles, sans germe retrouve. Le traitement probabiliste par Rocephine et Gentamycine s’avere inefficace. Un relais par Claforan-Vancomycine permet une evolution favorable ; mais a J22 on observe une recidive de la fievre associee a asthenie, hypotonie et geignement. Resultats La seconde PL revele une meningite devenue lymphocytaire avec culture positive a Listeria Monocytogenes. L’amelioration est rapide sous Amoxicilline-Gentamycine. Aucun deficit immunitaire n’est retrouve. On retrouve la consommation de camembert au lait cru 1 mois auparavant. Conclusions. Il est important de rappeler que la meningite a Listeria peut survenir en dehors de la periode neonatale, y compris chez les enfants immunocompetents. Le pronostic depend de la precocite du traitement. Une meningite a Listeria doit etre evoquee chez tout enfant ayant une meningite d’allure bacterienne sans germe retrouve, notamment en cas d’echec d’une antibiotherapie probabiliste bien conduite.

We investigated the inhibition of cell-cycle progression and replication and the induction of the transcriptional response in diploid budding yeast populations exposed to two different doses of γ-rays resulting in 15 and 85% survival respectively. We studied the kinetics of the cellular response to ionizing treatment during the period required for all of the surviving cells to achieve at least one cell division. The length of these periods increased with the dose. Irradiated populations arrested as large-budded cells containing partially replicated chromosomes. The extent of the S-phase was proportional to the amount of damage and lasted 3 or 7 h depending on the irradiation dose. In parallel to the division study, we carried out a kinetic analysis of the expression of 126 selected genes by use of dedicated microarrays. About 26 genes were induced by irradiation and displayed various pattern of expression. Interestingly, 10 repair genes ( RAD51 , RAD54 , CDC8 , MSH2 , RFA2 , RFA3 , UBC5 , SRS2 , SPO12 and TOP1 ), involved in recombination and DNA synthesis, display similar regulation of expression in the two irradiated populations. Their pattern of expression were confirmed by Northern analysis. At the two doses, the expression of this group of genes closely followed the extended replication period, and their expression resumed when replication restarted. These results suggest that the damage-induced response and DNA synthesis are closely regulated during repair. The analysis of the promoter regions indicates a high occurrence of the three MCB, HAP and UASH regulatory boxes in the promoters of this group of genes. The association of the three boxes could confer an irradiation-replication specific regulation.

The endovascular treatment of vasospasm is effective when implemented rapidly. However its indication often proves difficult on account of the lack of diagnostic arguments or the difficulties in obtaining them in daily practice. We report a case that highlights the relevance of MRI in the decision-making process. A 37-year-old patient presented with symptomatic vasospasm of the middle cerebral artery and was subjected to morphological, diffusion- and perfusion-weighted MRI. These investigations confirmed the presence of significant oligemia in the MCA territory and revealed onsetting diffusion disorders. Angioplasty was immediately performed, resulting in normal diffusion and hemodynamic parameters and complete regression of clinical signs. This case highlights the relevance of MRI when assessing vasospasm before treatment. Coupled with transcranial Doppler, it should help teams quickly select patients most likely to benefit from angioplasty.

Shortly before his death in 1995, Kenneth B. Schwartz, a cancer patient at Massachusetts General Hospital (MGH), founded The Kenneth B. Schwartz Center at MGH. The Schwartz Center is a nonprofit organization dedicated to supporting and advancing compassionate health care delivery, which provides hope to the patient, support to caregivers, and encourages the healing process. The center sponsors the Schwartz Center Rounds, a monthly multidisciplinary forum where caregivers reflect on important psychosocial issues faced by patients, their families, and their caregivers, and gain insight and support from fellow staff members. Burnout describes the end result of stress in the professional life of a physician or caregiver and combines emotional exhaustion, depersonalization and low personal accomplishment. This problem is common in health care workers in every specialty and may affect not only personal satisfaction, but also the quality of care delivered to patients. Burnout is particularly relevant in oncology where caregivers work closely with patients who have life-threatening illnesses and therapy often has only a limited impact. Burnout was discussed in the rounds with an emphasis on factors which precipitate or prevent stress among health care workers. Presentations were made by Dr. Canellos of the Dana Farber Cancer Institute, and Dr. Picard of the Institute for Health Professions. Staff discussed the main issues contributing to burnout including the health care system, lack of time and inadequate training. They considered preventative measures including psychological support of the health care team, communication and management skills, and effective coping mechanisms.

Cerebral sulci identification process is based on several formal rules: it consists a series of steps allowing the identification of the major sulci. The process may be variable for each of us and we propose to read the images in certain order starting with the frontal lobe and its superior frontal gyrus than precentral and central gyri followed by the lateral fissure. Then the insular, lateral parietal and medial hemispheric regions. Finally the major sulci within the temporal and occipital lobes are described in the frontal plane. This presentation indicates the principal rules of cerebral lobes'identification, the basis of variability perception and the localization of small lesions allowing an accurate correlation with clinical findings and a suitable therapeutic procedure.

We report a case of an asymptomatic vasospasm with a focal, reversible apparent diffusion coefficient (ADC) decrease after a middle cerebral artery aneurysm rupture. This isolated decrease of ADC has not yet been reported in this pathological situation. It could be interesting to predict the risk of ischemic delayed complications of vasospasm.

Depriving the ovary of exogenous FSH for 1, 2 or 3 d following a bolus injection of FSH was shown to influence the quality of the recovered oocytes. Thus, we compared the developmental competence of oocytes from heifers which had been stimulated for 3 d with FSH (Folltropin-V) and, after an interval of 36, 48 or 60 h, underwent blind transvaginal aspiration. The ovaries of heifers with a palpable or functional corpus luteum were aspirated to remove all large follicles 2 d prior to being injected with either 6 doses of saline (S), 6 doses (20 mg/mL) of FSH (F), or in 6 decreasing doses of FSH (3, 3, 2, 2, 1, 1 mL; Fd). Follicles were counted and classified (medium: 5 to 10 mm, large: >10 mm) with ultrasonography before each aspiration. The oocytes recovered were classified, matured, fertilized, and developed in vitro. On a per animal basis, 1.5, 5.2 and 4.7 large and 1.5, 10.7 and 10.7 medium follicles were counted for S, F and Fd, respectively. A mean of 3.3, 9.1 and 7.7 oocytes was recovered for treatments S, F and Fd, respectively and 58, 94 and 82% were enclosed in a nonexpanded cumulus or a corona layer. Oocyte development rates were based on counts of embryos with 32 or more nuclei at Day 6.5. When oocytes were recovered 36 h after the last injection, an average of 1, 2.7 and 2 embryos per animal was obtained with S, F and Fd, respectively; at 48 h, 0.75, 4.25 and 1 embryo; and at 60 h, 0, 2.5 and 2.7 embryos. Variance analysis was performed, and the protected LSD test indicated that treatment F at 48 h resulted in a significantly higher embryo rate than Fd at 48 h (P

The aim of our study was to evidence the location of the cortical area triggered by visual memory tasks by he mean of functional magnetic resonance imaging examination (fMRI).Twelve healthy volunteers underwent fMRI examination on a 1.5 Tesla magnet with echoplanar imaging sequence during figurative and non-figurative memory tasks. An area was considered to be activated if at least 10 contiguous voxels activation was noted. Activated areas were defined for both tasks and the brain mapping was realized according to Talairach atlas.For all examinations a bilateral activity was evidenced (area 17 and 18). In addition, a frontal activation was also noted in 83% of the cases for both tasks. However, frontal activation was bilateral in 9/10 cases for the figurative task and 6/10 cases for the non-figurative task.FMRI was able to evidence activation of cerebral areas during visual memory tasks in all our study cases. Frontal activation was not discriminative of figurative or non figurative memory. This might be probably explain by inappropriate non-figurative tests. FMRI should allow a better knowledge of memory mechanisms as well as an enhancement of functional cerebral mapping before surgery.

3D angiography is a true technical revolution that allows improvement in the quality and safety of diagnostic and endovascular treatment procedures. 3D angiography images are obtained by reconstruction of a rotational angiography acquisition done on a C-arm (GE Medical Systems) spinning at 40 degrees per second. The carotid or vertebral selective injection of a total of 15 ml of non-ionic contrast media at 3 ml/sec over 5 seconds allows the selection of the "arterial phase". Four hundred sixty 3D angiographic studies were performed from December 1996 to September 1998 on 260 patients and have been analyzed in MIP (Maximum Intensity Projection) and SSD (Shaded Surface Display) views. The exploration of intracranial aneurysms is simplified and only requires, for each vascular axis, a biplane PA and Lateral run followed by a single rotational angiography run. The 3D angiography image is available on the workstation's screen (Advantage Workstation 3.1, GE Medical Systems) in less than 10 minutes after the acquisition of the rotational run. It therefore allows one to analyze, during the intervention, the aneurysm's angioarchitecture, in particular the neck, and select the best therapeutic technique. When endovascular treatment is the best indication, 3D angiography allows one to define the optimal angle of view and accurately select the microcoils dimensions. 3D angiography replaces the multiple oblique views that used to be required to analyze the complex aneurysms and therefore allows a reduction of the total contrast medium quantity, the patient X-ray dose and the length of the intervention time which is a safety factor. Also, in particular for complex cases, it brings additional elements complementing the results of standard 2D DSA and rotational angiograms. In the cervical vascular pathology, 3D angiography allows for a better assessment of the stenosis level and of dissection lesions. Our current research activities focus on the matching without stereotactic frame between 3D X-ray angiography and volumetric MR acquisition, which should allow us to improve the treatment of intracerebral arterio-venous malformations (AVMs).

Crack, the free-base form of cocaine, was introduced as an illicit street drug in 1986. Since then, we have noted a significant increase in acute gastroduodenal perforations. Between 1982 and 1986, we treated 11 patients with such perforations. This represents a constant occurrence rate of 6% of hospital admissions for peptic ulcer disease. Since 1986 we have treated 16 patients with gastroduodenal perforation, which yields an occurrence rate of 16%. Nine of the 16 patients had a close temporal relationship between the use of crack and the onset of their perforation. This group was younger and disproportionately comprised of male patients. These findings led us to believe that there may be a pathogenic relationship between the use of crack and acute gastroduodenal perforation, and the clinician should be aware of the various potential complications of this new drug. This relationship also raises questions about the exact pathophysiology of peptic ulcer disease.

The foraging behaviour of bumble bees is well documented for nectar and/or pollen gathering, but little is known about the learning processes underlying such behaviour. We report olfactory conditioning in worker bumble bees Bombus terrestris L. (Hymenoptera: Apidae) obtained under laboratory conditions on restrained individuals. The protocol was adapted from the proboscis extension conditioning previously described in the honey bee Apis mellifera L. Bumble bees were found to be able to learn a pure odorant when it was presented in paired association with a sugar reward, but not when odour and reward were presented in an explicitly unpaired procedure. This suggests an associative basis for this olfactory learning. Bumble bees showed similar conditioning abilities when stimulated with two different floral odours. An effect of the sugar reward concentration on the learning performances was found.

A model based on the diffusion of the vortices is proposed in order to describe the flux creep and the flux flow regimes in high Tc films in which a bias current flows when no large magnetic field is applied. We show how it is possible, from the results of the model, to estimate the effective superconductive thickness of the samples and the main quantities characterizing the flux creep regime. In the flux flow regime, the model accounts for the non-linear current- voltage curves which are actually measured.

The spinal canal is an uncommon site for abscess formation resulting from bloodstream disseminated infection. Prognosis is often unfavorable. Rapid treatment is essential for satisfactory neurological recovery. Abscesses within the spinal canal are thus diagnostic and therapeutic emergencies. The neuro-infectious and inflammatory manifestations and laboratory findings vary considerably and are insufficient for diagnosis. MRI plays a decisive role. The most commonly reported signs are the presence of an intramedullary collection giving a low-intensity signal on T1-weighted images and a high-intensity signal on T2-weighted images with peripheral contrast uptake and generally extended adjacent medullary edema. We report here five cases of spinal canal abscesses diagnoses with MRI at different stages of development (pre-suppurative myelitis in two cases, constituted abscess in three cases). For each case we reviewed the clinical course and describe the details of the imaging findings. In our series, the collected abscesses presented as round lesions within the canal with contrast uptake. It is noteworthy that the periependymal gray matter adjacent to the lesion also took up the contrast agent in all patients with a collected abscess. This sign has not been described previously and appears to be a going argument orienting the diagnosis towards an infectious rather than tumoral formation.

This article describes a health promotion project for teens in a rural francophone community in Northern Ontario. A planning committee of two community health nurses and eight teenagers developed, implemented and evaluated the project. Based on teen interest generated in the community, the committee planned a youth snowmobile day to help identify and define the teenagers' particular health needs. The aim was to facilitate youth participation at every step of the project, from needs assessment to follow-up, and encourage them to explore, with their peers, ways to improve their health. A qualitative research approach was used to study and document the event. A total of 48 girls and boys in the 13-19 age group took part. Stopovers were held at various inns for group discussions on predetermined topics. Study results indicate that when power is shared with teenagers, important lessons are learned by both parties. In such a partnership, nurses need to use more than the educational approach to interventions. Their role as community development facilitators is highlighted, as well as their need to develop novel and unique approaches for dealing with teenagers.

Chickens from three genetic stocks known to differ in growth potential consumed ad libitum either a single (control) diet or a choice of two diets that differed in protein and energy. Formulation of the choice diets was such that when mixed in specific proportions they provided single diets that decreased in protein and increased in energy over the experimental period. When comparisons of feeding regimens were made at a common age, body weights and feed efficiencies for all stocks were enhanced in chicks fed a single diet. When comparisons were made at a common body weight for controls, chickens fed the single diet were about 15% heavier than those given a dietary choice. For feed efficiency, however, the pattern remained for the faster growing stock whereas there was no difference between feeding regimens for the slower growing stock. Chicks provided a choice of diets had heavier abdominal fat pads and lighter breasts relative to body weight than those fed a single diet. With choice feeding, there were stock by diet interactions for dietary preferences through the first 9 d after hatch. Early on, the interactions resulted from the faster growing stocks exhibiting a greater preference for the diet higher in protein and lower in energy than the slower growing stock. By Day 5, however, the interaction occurred because stocks exhibited either no dietary preference or preferred the diet that was lower in protein and higher in energy. Regardless of genetic stock, at 9 d of age and thereafter there was a clear preference for the diet lower in protein and higher in energy than the diet higher in protein and lower in energy. These data for feed intake were consistent with behavioral observations that showed a preponderance of chicks eating from the feeder containing the diet lower in protein and higher in energy. Compared to a single diet, under choice feeding, energy utilization was negatively influenced more in the faster than slower growing stocks. Protein and sulfur amino acid utilization was not affected by feeding regimen in faster growing stocks, but was enhanced under choice feeding in the slower growing stock. Although lysine utilization was enhanced by choice feeding in all stocks, the effect was greater in the slower than in the faster growing ones. These data demonstrate that although broiler diets are formulated to enhance growth and overall feed efficiency, chicks that are provided a dietary choice of protein and energy do not eat to maximize growth or feed efficiency.