bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deficiencies in Concussion Education in Canadian Medical Schools
Authors: Burke Matthew J. , Chundamala Josie , Tator Charles H. 
Published: December 2014

Background:Recent reports raise concern that physician knowledge of the identification and management of concussion may be deficient. There is little information known about the adequacy of concussion education provided to physicians or medical students. The present study assesses the concussion curriculum offered at medical schools in Canada.Methods:We asked all 17 Canadian medical schools to complete a questionnaire on their concussion curriculum, including the following: year of medical school offered; format/setting; and estimated teaching hours. The responses were organized into three categories: (1) concussion-specific education; (2) head injury education incorporating a concussion component; and (3) no concussion education.Results:Replies were received from 14 (82%) of the 17 medical schools in Canada. Of the 14 responding schools, four (29%) provided concussion-specific education, six (43%) offered head injury education that incorporated a concussion component, and four (29%) reported no concussion teaching in their curriculum.Conclusion:We found deficiencies in the concussion education curriculum provided in the majority of Canadian medical schools. To address this issue, we recommend that all medical schools should, at a minimum, include a one-hour formal concussion-specific teaching session in an early year of their curriculum to be followed by clinical exposure to concussed patients in the later years of medical school. Future studies will be necessary to evaluate if these recommended curricular enhancements are effective in remedying the reported gaps in physicians' concussion knowledge and whether the improved curriculum translates into better care for patients suffering concussion.
Hemangioblastoma Stromal Cells Show Committed Stem Cell Phenotype
Authors: Welten Cassandra M. , Keats Emily C. , Ang Lee-Cyn , Khan Zia A. 
Published: December 2014

Background:Hemangioblastomas are benign vascular tumors of the central nervous system that occur sporadically or in association with von Hippel-Lindau disease. These tumors are characteristically composed of a dense capillary network with intervening stromal/interstitial cells. To date, the histogenesis of hemangioblastoma remains unclear. We hypothesize that hemangioblastomas arise from a defective mesodermal stem cell, which gives rise to the atypical vasculature.Methods:To test our hypothesis, we have characterized the cellular composition of hemangioblastomas by immunophenotyping pluripotent and committed stem cells and vascular endothelial cells.Results:Our findings show that hemangioblastoma endothelial cells are positive for CD133, a stem and progenitor cell marker. Vascular endothelial cells also expressed nuclear Oct4. In addition to the endothelium, both CD133 and Oct4 were present in stromal and perivascular cells. Interestingly, neither the endothelium nor the stromal cells expressed Sox2 or Nanog suggesting a committed stem cell phenotype.Conclusions:From these findings, we believe that hemangioblastoma stromal cells are committed stem cells producing both vascular cell types. The findings also show an unusual CD133-positive endothelial phenotype in hemangioblastoma.
Gamma Knife Radiosurgery for High Grade Glial Neoplasms: A Canadian Experience
Authors: Zeiler F.A. , Kaufmann A.M. , McDonald P.J. , Fewer D. , Butler J. , Schroeder G. , West M. 
Published: December 2014

Object:To review our institutional experience with Gamma Knife (GK) stereotactic radiosurgery in treating focally recurrent high grade glial neoplasms of World Health Organization (WHO) grade III or IV.Methods:We conducted a retrospective cohort review of all patients treated with GK for focally recurrent high grade gliomas at our institution between November 2003 and April 2013. Data on age, sex, tumor volume, location and maximal diameter, presenting clinical status, complications and clinical outcome was recorded.Results:A total of 33 patients were identified. Four were lost to follow-up. Average post-GK and overall survival was 20.4 months (range: 3 – 72) and 63.3 months (range: 10 – 214) respectively. For WHO grade IV gliomas, the average post-GK and overall survival was 15.8 months (range: 3 – 77) and 40.1 months (range: 13 – 148) respectively. Similarily, for WHO grade III gliomas, the average post-GK and overall survival was 34.9 months (range: 6 – 72) and 136.4 months (range: 22 – 214) respectively. Twenty-two patients (75.9%) had post-GK edema, with 14 requiring dexamethasone and eight being asymptomatic. Four patients (13.8%) had imaging defined radiation necrosis.Conclusions:Gamma Knife SRS affords an extension of local tumor control, acceptable morbidity, and potentially prolonged survival, for highly selected patients with focally recurrent high grade glial neoplasms.
Radiologic Patterns of Necrosis After Proton Therapy of Skull Base Tumors
Authors: Korchi Amine M. , Garibotto Valentina , Lovblad Karl-Olof , Haller Sven , Weber Damien C. 
Published: December 2014

Background:Discrimination between radiation necrosis and tumor progression after radiation therapy represents a radiologic challenge. The aim of our investigation is to identify patterns of radiation necrosis on brain magnetic resonance imaging (MRI) and positron emission tomography (PET) with Fluoroethyltyrosin (FET) after proton beam therapy (PBT) for skull base tumors.Material and Methods:Five consecutive patients with extra-axial neoplasms were included, presenting a total of eight radiation necrosis lesions (three clival chordomas; two petroclival chondrosarcomas; two women; mean age: 49 ± 18.2 years). Radiation necrosis was defined as the appearance of abnormal enhancement on MRI after PBT decreasing over time, and additional histopathologic confirmation in one patient. MRI and PET imaging were retrospectively analyzed by two experienced radiologists in consensus.Results:All lesions were localized close to the primary tumor in the field of irradiation. Three patients showed bilateral symmetrical lesions. All lesions showed T2 hyperintensity and T1 hypointensity. Cerebral blood volume (CBV) was reduced in all available studies. None of the lesions showed a restricted diffusion. FET-PET (three patients) showed a higher uptake in four out of five lesions; three of which had a mean tumor-to-background (TBRmean) uptake lower than 1.95 and FET uptake increasing over time and were correctly classified into radiation necrosis.Conclusions:Most radiation necroses were in direct continuity with the primary tumor mimicking tumor progression. The most consistent imaging findings for PBT radiation necrosis are low CBV without restricted diffusion and FET-PET TBRmean lower than 1.95 or increasing uptake over time. Bilateral symmetric involvement may be another indicator of radiation necrosis.
Factors Determining the Clinical Complications of Radiosurgery for AVM
Authors: Machnowska Matylda , Taeshineetanakul Patamintita , Geibprasert Sasikhan , Menezes Ravi , Agid Ronit , Terbrugge Karel G. , Andrade-Souza Yuri , Schwartz Michael L. , Krings Timo 
Published: December 2014

Purpose:To identify the predictors of symptomatic post-radiation T2 signal change in patients with arteriovenous malformations (AVM) treated with radiosurgery.Materials and Methods:The charts of 211 consecutive patients with arteriovenous malformations treated with either gamma knife radisurgery or linear accelerator radiosurgery between 2000-2009 were retrospectively reviewed. 168 patients had a minimum of 12 months of clinical and radiologic follow-up following the procedure and complete dosage data. Pretreatment characteristics and dosimetric variables were analyzed to identify predictors of adverse radiation effects.Results:141 patients had no clinical symptomatic complications. 21 patients had global or focal neurological deficits attributed to symptomatic edema. Variables associated with development of symptomatic edema included a non-hemorrhagic symptomatic presentation compared to presentation with hemorrhage, p=0.001; OR (95%CI) = 6.26 (1.99, 19.69); the presence of venous rerouting compared to the lack of venous rerouting, p=0.031; OR (95% CI) = 3.25 (1.20, 8.80); radiosurgery with GKS compared to linear accelerator radiosurgery p = 0.012; OR (95% CI) = 4.58 (1.28, 16.32); and the presence of more than one draining vein compared to a single draining vein p = 0.032; OR (95% CI) = 2.82 (1.06, 7.50).Conclusions:We postulated that the higher maximal doses used with gamma knife radiosurgery may be responsible for the greater number of adverse radiation effects with this modality compared to linear accelerator radiosurgery. We found that AVMs with greater venous complexity and therefore instability resulted in more adverse treatment outcomes, suggesting that AVM angioarchitecture should be considered when making treatment decisions.
Presurgical Language fMRI and Postsurgical Deficits: A Single Centre Experience
Authors: Wiens Charmaine , Goodyear Bradley G. , Goel Ankur , Federico Paolo , Hader Walter , Goyal Mayank 
Published: December 2014

Background:In this study, we conducted a retrospective investigation of our initial single-centre experience with the clinical use of functional magnetic resonance imaging (fMRI) of hemisphere dominance for language processing (i.e., language lateralization). We demonstrated its association with surgical outcome and its potential impact on surgical planning and patient management.Methods:Fifty-two cases were reviewed, covering the period from July 2007 to July 2010. Clinical fMRI reports were examined to determine the hemisphere dominance for language processing. Neurological reports were examined to determine if new language deficits were present post-surgery. Neurosurgeon notes were also reviewed to determine if fMRI had an impact on surgical planning.Results:Of the cases reviewed, 49 (94%) generated conclusive fMRI. Eleven (22%) patients exhibited fMRI language lateralization contralateral to pathology; zero of nine of these patients that had surgery experienced post-surgical deficits. Twenty-two (44%) patients exhibited fMRI language lateralization ipsilateral to pathology; three of 13 of these patients that had surgery experienced post-surgical deficits. Sixteen (34%) patients exhibited bilateral lateralization of language; five of 13 of these patients that had surgery experienced post-surgery deficits. Several post-fMRI reports indicated that fMRI results had an impact on surgical planning.Conclusions:Our results suggest that fMRI demonstrations of language processing within the hemisphere ipsilateral to pathology (either ipsilateral alone or bilateral) is associated with a greater risk for post-surgical language deficits, and in these cases, fMRI results should be taken into consideration for pre-surgical planning.
Can Behenic Acid (C22:0) Levels be a Prognostic Factor in Glial Tumors?
Authors: Kaplan Metin , Koparan Mehmet , Sari Aysel , Ozturk Sait , Kaplan Serpil Kozan , Erol Fatih Serhat 
Published: December 2014

Background:Inhibition of fatty acid synthase leads to apoptosis in cancers, which leads to high levels of fatty acid synthesis. This indicates that cancer cells depend on fatty acid in order to survive. In this study, we investigated whether or not there was a relationship between the glial tumor grade and free fatty acid level of tumor tissue.Methods:Twenty patients who had high grade glial tumors and 20 patients who had low grade glial tumors, were included in the study. Tumors samples were obtained intraoperatively in order to measure the fatty acid levels. The fatty acids were studied in three groups: saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids. They were analyzed with gas chromatography.Results:The oleic acid, linoleic acid, eicosadienoic acid, arachidonic acid, and docosadienoic acid levels were high in the tumor tissue of low grade tumors. The myristic acid, palmitic acid, stearic acid, alpha linoleic acid, eicosenoic acid, dihomo-gamma-linolenic acid, docosahexaenoic acid, and ceramide levels were high in the tumor tissue of high grade glial tumors. However, none of these high values were statistically significant. The high values of behenic acid, a saturated fatty acid, in low grade glial tumors were statistically significant.Conclusion:High levels of behenic acid in patients with low grade glial tumor is important as it indicates persistence of the tissue integrity and tissue resistance. behenic acid levels can be a prognostic factor in glial tumors.
Review of Awakening Agents
Authors: DeMarchi Ryan , Bansal Vikas , Hung Anthony , Wroblewski Karol , Dua Hemi , Sockalingam Sanjeev , Bhalerao Shree 
Published: December 2014

ABSTRACT:Brain injuries are a serious burden of illness to Canada and the US. Advances in managing head trauma have allowed more patients to emerge from decreased levels of consciousness and helped them cope with neurocognitive, neurobehavioural, and neuropsychiatric deficits. In this article, we review the current (1986-2002) evidence surrounding the pharmacological management of arousal states and the aforementioned neurological sequelae of head injury in either acute or chronic conditions. This article will review the evidence for the use of psychostimulants (methylphenidate), antidepressants (amitriptyline, selective serotonin reuptake inhibitors, and buproprion), Parkinson’s medications (amantadine, bromocriptine, carbidopa/levodopa), anticonvulsants (valproic acid), modafinil (Provigil), lactate, hyperbaric oxygen chamber, electroconvulsive therapy, and transmagnetic stimulation, in patients following a head injury. The review did not include all anticonvulsants, neuroleptics, beta-blockers, benzodiazepines, azospirones or cognitive enhancers. Unfortunately, the quality of the evidence is generally poor, and sometimes conflicting, which in turn results in indecisive guidelines for treating patients. Accepting the inherent flaws in the evidence we feel that this paper may serve as a stepping-stone for future researchers to improve data gathering that targets neurocognitive, neurobehavioural and neuropsychiatric symptoms following a head injury.
Anterograde Ventricular Irrigation During Fourth Ventricle Region Surgery
Authors: Fleetwood Ian G. , Hamilton Mark G. 
Published: December 2014

Objective:To reduce postoperative hydrocephalus following surgery in the region of the fourth ventricle.Method/technique:We describe the use of a conventionally placed lateral ventricular catheter to facilitate anterograde ventricular irrigation during surgery in the region of the fourth ventricle. This technique offers a safe alternative to more conventional approaches to fourth ventricular irrigation and obviates the need for placement of a third or fourth ventricular catheter and/or serial lumbar punctures by thoroughly flushing blood and tissue debris from the operative field at the time of surgery.Results:Preliminary results spanning a five-year period show a lower incidence in the need for early ventriculo-peritoneal shunts (5%) and delayed ventriculo-peritoneal shunts (10%).Conclusion:This technique represents a safe method of reducing hydrocephalus following operative procedures in the region of the fourth ventricle.
Electrogastrography in Patients with Parkinson’s Disease
Authors: Naftali T. , Gadoth N. , Huberman M. , Novis B. 
Published: December 2014

Background:Impaired gastrointestinal motility in Parkinson’s disease may affect absorption of levodopa and contribute to the disabling response fluctuations (RF). In this study gastric myoelectric activity was recorded with electrogastrography in patients with PD and correlated with the duration, severity and the presence of RF.Method:Electrogastrography (EGG) was performed in 36 patients with PD of which 22 were men. The mean age was 67 years (48-81), mean duration of disease was 7.07 years (1-20), and mean duration of treatment with levodopa was 5.07 years (1-20). Gastric dysrrythmia was diagnosed when either preprandial or postprandial dysrrythmia for more than 30% of the recording period was detected.Results:The EGG was abnormal in 24 of 36 patients. Significant association was found between preprandial dysrrythmia and duration of disease (P=0.002); duration of levodopa treatment (P=0.003), severity of 86RF (P=0.001), but not with age (P=0.076). Out of 18 patients with RF, 17 had at least one pattern of dysrrythmia. In 11 out of the 18 patients without RF, the EGG was normal while the remaining seven had at least one pattern of dysrrythmia.Conclusion:Abnormal EGG was quite common in this group of patients with PD, particularly in those with RF. The most common pattern of abnormality was preprandial dysrrythmia, which was positively associated with disease duration and length of levodopa treatment. Although frequently asymptomatic, preprandial dysrrythmia leading to impaired gastric emptying may contribute to irregular absorption of levodopa from the small intestine and contribute to disabling response fluctuations.
Clobazam as Add-on Therapy for Temporal Lobe Epilepsy and Hippocampal Sclerosis
Authors: Montenegro Maria Augusta , Ferreira Claudio Meilman , Cendes Fernando , Li Li M. , Guerreiro Carlos A.M. 
Published: December 2014

Background:Clobazam is a benzodiazepine with known antiepileptic action; however, it is not considered first line therapy in the treatment of epilepsy. The objective of this study was to evaluate the efficacy of clobazam as add-on therapy in adults with temporal lobe epilepsy associated with MRI evidence of hippocampal sclerosis (HS).Method:This is a retrospective study, conducted at our epilepsy clinic which evaluated clobazam as add-on therapy in patients with temporal lobe epilepsy and MRI signs of HS. Clobazam was prescribed based on the minimum effective dose up to the maximum tolerated dose.Results:Seventy-eight patients met the inclusion criteria (51 women), ages ranging from 16 to 76 years old (mean=42.2). Dosage of clobazam ranged from 5 to 60 mg/day (mean=22.6 mg/day). Clobazam was used from one month to eight years (mean=29 months). Sixteen (20.5%) patients were seizure-free, 20 (25.5%) had more than 75% improvement in seizure control, eight (10%) had more than 50% and 20 (26%) were non responders to clobazam. In 14 (18%) we could not determine seizure frequency during follow-up. The improvement in seizure control lasted for more than one year in 30 (68%) patients.Conclusion:Our data suggest that clobazam should be considered as add-on therapy in the treatment of patients with temporal lobe epilepsy associated with MRI signs of HS.
Vulture populations in Uganda: using road survey data to measure both densities and encounter rates within protected and unprotected areas
Authors: POMEROY DEREK , SHAW PHIL , OPIGE MICHAEL , KAPHU GEORGE , OGADA DARCY L. , VIRANI MUNIR Z. 
Published: December 2014

SummarySix out of seven vulture species whose global ranges lie largely or wholly within Africa are listed as globally threatened. Since their current distributions individually span up to 39 range states there is a pressing need to develop robust, standardised methods that provide a clear measure of range-wide changes in abundance. Yet, survey methods currently used tend to yield either of two measures: estimates of breeding density, derived mainly from nest counts; or linear encounter rates, derived from road surveys. Here, we present the results of a six-year survey of six vulture species in Uganda, in which we used road counts, in combination with Distance sampling, to determine both encounter rates and densities within protected areas (PAs), and in predominantly pastoral and agricultural areas. In combination, five scavenging species were detected 4–6 times more frequently in PAs than elsewhere, and two species, White-backed Vulture Gyps africanus and Lappet-faced Vulture Torgus tracheliotus, were recorded only within PAs. We estimate that PAs held c.1,300–3,900 individuals of the five scavenging species combined, including c.1,250–2,900 individuals of two Gyps species. We also present national population estimates for two species: White-backed Vulture (c.1,000–2,600 birds) and Lappet-faced Vulture (c.160–500 birds). Although sightings were assigned to only three broad distance bands, Distance sampling provided estimates with a level of precision similar to that achieved for linear encounter rates, but as density estimates; a form more readily comparable with results obtained from other survey types.
Upgraded heart failure therapy leads to an improved outcome of dilated cardiomyopathy in infants and toddlers
Authors: Rupp Stefan , Apitz Christian , Tholen Leonie , Latus Heiner , Ostermayer Stefan H. , Schmidt Dorle , Bauer Jürgen , Schranz Dietmar 
Published: December 2014

AbstractObjectiveDilated cardiomyopathy is a leading cause of cardiac death in children. Approximately 30% of children die or need cardiac transplantation in the first year after establishing the diagnosis. New strategies are needed to improve the outcome in this high-risk patient population.Method and resultsWe present our experience in 38 patients below the age of three years, who were diagnosed with dilated cardiomyopathy and who were treated at our institution between 2006 and 2012. The treatment strategy involved institution of β-blockers and angiotensin-converting enzyme inhibitors as soon as feasible. In selected cases, pulmonary artery banding or intracoronary autologous bone marrow-derived cell therapy was performed. The median age at presentation was six months (range 1–26 months). The median follow-up age was 16 months (range 2–80 months). Kaplan–Meier analysis of survival after dilated cardiomyopathy diagnosis revealed a one-year survival of 97% and a five-year survival of 86%. The rate of freedom from death or heart transplantation was 82% at one year and 69% at five years. Surviving patients who were free of transplantation, at the follow-up at 25 months (3–80 months), showed a significant improvement in left ventricular ejection fraction (from 19±11 to 46±16%) and left ventricular end-diastolic diameter (z-score from 4.6±2.4 to 1.4±1.6). In addition, the levels of B-type natriuretic peptide improved significantly (from 3330±3840 to 171±825 pg/ml).ConclusionOur data suggest that the clinical approach described here may result in a markedly improved medium-term outcome in young children with dilated cardiomyopathy. Further studies are required to evaluate whether these approaches reduce end-points such as transplantation or death.