bluuebunny/crossref_metadata_2025 huggingface dataset:
Climate change and modelled biome representation in Canada's national park system: implications for system planning and park mandates
Authors: Scott Daniel , Malcolm Jay R. , Lemieux Christopher
Published: March 2003

Aim  The study examined the potential for change in biome representation within Canada's national park system under multiple climate change scenarios and subsequent potential vulnerabilities in Parks Canada policy and planning frameworks.

Location  The study was conducted for Canada's 39 national parks.

Methods  The vegetation change scenarios were based on modelling results from the BIOME3 and MAPSS equilibrium process‐based global vegetation models (GVM), run with multiple doubled‐CO2 climate change scenarios. The six vegetation distribution scenarios were calculated at 0.5° latitude–longitude resolution and the boundaries of 39 national parks superimposed in a geographic information system (GIS). Park management plans and other planning documents were also reviewed as part of the analysis.

Results  The proportional distribution of biomes in Canada's national park system was very similar (within 3% of area for each biome) using BIOME3 and MAPSS under the current climate. Regardless of the GVM and climate change scenario used, the modelling results suggest the potential for substantial change in the biome representation in Canada's national park system. In five of six vegetation scenarios, a novel biome type appeared in more than half of the national parks and greater than 50% of all vegetation grid boxes changed biome type. The proportional representation of tundra and taiga/tundra in the national park system declined in each of the vegetation scenarios, while more southerly biomes (temperate forests and savanna/woodland) increased (in some scenarios doubling to quadrupling). Results for boreal forest varied among the climate change scenarios. A range of potential vulnerabilities in existing policy and planning frameworks were identified, including the national park system plan, individual park objectives, and fire and exotic species management plans.

Conclusions  Climate change represents an unprecedented challenge to Parks Canada and its ability to achieve its conservation mandate as presently legislated. Research is needed not only on ecosystem responses to climate change, but also on the capacity of conservation systems and agencies to adapt to climate change.
Robustness of the maximum‐likelihood‐binomial approach for linkage analysis of quantitative trait loci with non‐normal phenotypic data
Authors: Alcaïs Alexandre , Abel Laurent
Published: March 2003

Introduction Model‐free linkage studies are increasingly used to investigate the genetic factors implicated in complex quantitative traits because they do not require any specification of the underlying genetic model. However, the term model‐free does not imply that no assumption is introduced by the corresponding statistical methods. In particular, the widely used variance components approaches assume multivariate normality of the phenotypic distribution and it has been shown that violation of this normality hypothesis could lead to large inflation of the type I error. In this paper, we assess the robustness of the recently developed sibship‐oriented Maximum‐Likelihood‐Binomial (MLB) method for genetic model‐free linkage analysis in the context of several types of non‐normal phenotypic data using a large simulation study.

Simulation study Under the hypothesis of no linkage at the marker locus under study, 20 000 replicates of family samples including 100 or 500 independent sib‐pairs were simulated considering four different designs that lead to non‐normal phenotypic data: (1) presence of a major gene not linked to the studied marker, (2) gene–environment interaction, (3) analysis of a binary phenotype, and (4) extreme sampling. Further, three levels of residual sib–sib correlation were considered.

Results and discussion For each simulation design the empirical type I errors were consistent with their asymptotic expectations showing that the MLB approach is insensitive to non‐normal phenotypic distribution whatever the mechanism underlying this non‐normality. Therefore, the MLB method should be an attractive alternative method for model‐free linkage analysis of QTL, especially for investigators who do not want to worry about the validity of asymptotic thresholds when performing their analyses.
Transgenic fish: an evaluation of benefits and risks
Authors: Maclean N. , Laight R.J.
Published: March 2003

Transgenic fish have many potential applications in aquaculture, but also raise concerns regarding the possible deleterious effects of escaped or released transgenic fish on natural ecosystems. In this review the potential applications of transgenic fish are considered, the probable benefits reviewed, the possible risks to the environment identified and the measures which might be taken to minimize these risks are evaluated. Growth trials of transgenic fish have already been carried out in outdoor facilities and some of these are discussed in the light of possible risks and benefits. Regarding the hazards associated with release or escape, whilst there is some evidence to suggest that transgenic fish may be less fit compared to their wild counterparts, there is insufficient evidence to say that this will be true in all cases. Using mathematical models, we have attempted to predict the magnitude of the genetic effects in a range of different scenarios. A number of possible containment techniques are considered, amongst which containment by sterility is probably the most promising. This can be engineered either by triploidy or by transgenic methods. The conclusions include a tabulated balance sheet of likely benefits and risks, with appropriate weighting.
Species concepts and speciation of fishes: concluding remarks
Authors: R Stauffer Jay , Kocovsky Patrick M , Ruffing Renea A
Published: March 2003

The definition of the species category has stimulated more debate than perhaps any other topic in the biological sciences. There are currently more than 22 different species concepts and the debate continues on which concepts apply to all organisms, which concepts are operational and which concepts should be used in specific circumstances. The first major division of the types of concepts depends on whether one views species as constructs that exist for ordering biodiversity and information retrieval (i.e. classes), or views species as ontological individuals that exist in nature. If species are categories that can be defined, then theoretically, a single species can arise more than once in different places or at different times. If, on the other hand, species are individuals, then they are historical events, monophyletic and each species is unique.
Postischemic changes of [3H]nimodipine and [3H]ryanodine binding in the gerbil striatum and hippocampus
Authors: Araki T. , Kato H. , Shuto K. , Oshima Y. , Itoyama Y.
Published: March 2003

Sequential alterations of [3H]nimodipine and [3H]ryanodine binding in gerbils were investigated in selectively vulnerable regions, such as the striatum and hippocampus, 1 h to 7 days after 10 min of transient cerebral ischemia. [3H]Nimodipine binding showed no significant changes in the striatum and hippocampus up to 48 h after ischemia. Seven days after ischemia, however, a severe reduction in [3H]nimodipine binding was observed in the dorsolateral striatum, hippocampal CA1 (stratum oriens, stratum pyramidale and stratum radiatum) and hippocampal CA3 sector. On the other hand, [3H]ryanodine binding showed a significant increase in the hippocampus 1 h after ischemia. Five hours after ischemia, a significant reduction in [3H]ryanodine binding was observed only in the hippocampal CA1 sector. Thereafter, the striatum and hippocampus showed no significant alterations in [3H]ryanodine binding up to 48 h after ischemia. After 7 days, a marked reduction in [3H]ryanodine binding was observed in the striatum and hippocampus which were particularly vulnerable to ischemia. These results demonstrate that postischemic alteration in [3H]nimodipine and [3H]ryanodine binding is produced with different processes in the hippocampus. They also suggest that the mechanism for striatal cell damage caused by transient cerebral ischemia may, at least in part, differ from that for hippocampal neuronal damage. Furthermore, our findings suggest that abnormal calcium release from intracellular stores may play a pivotal role in the development of hippocampal neuronal damage.
Demonstration of delayed recovery from fatiguing exercise in chronic fatigue syndrome
Authors: Paul Lorna , Wood Leslie , Behan Wilhelmina M.H. , Maclaren William M.
Published: March 2003

Patients with the chronic fatigue syndrome (CFS) complain consistently of delay in recovery of peripheral muscle function after exercise. The purpose of this study was to try to confirm this observation. A fatiguing exercise test was carried out on the quadriceps muscle group of ten patients and ten control subjects. The test consisted of 18 maximum voluntary contractions (MVCs) with a 50% duty cycle (10 s contraction, 10 s rest), and the force generated by each contraction was recorded using a KinCom dynamometer. This was followed by a recovery phase lasting 200 min in which quadriceps strength was evaluated at increasing intervals, and a follow‐up session at 24 h post‐exercise involving three 10 s MVCs. Throughout the exercise period, the MVCs obtained from the control group were significantly higher than those of the patient group (P = 0.006), but both groups showed a parallel decline in force over the 18 contractions, in keeping with a similar endurance capacity. Recovery was prolonged in the patient group, however, with a significant difference compared to initial MVCs being evident during the recovery phase after exercise (P = 0.001) and also at 24 h (P < 0.001). In contrast, the control group achieved MVCs which were not significantly different from initial values during the recovery phase, and maintained these at 24 h. These findings support the clinical complaint of delayed recovery after exercise in patients with CFS.
Neurology in the electronic information age
Authors: Busis Neil A.
Published: March 2003

This review discusses the state of neurology and the Internet at the turn of the millennium. First, some basic definitions about the Internet and its component protocols are presented. Next, ways neurologists and patients can use the Internet are enumerated. Internet resources or applications are available or are being created that can aid in the successful fulfillment of a neurologist's core professional activities: clinical care, teaching, research, and practice issues. Currently, the most useful categories of Internet resources for neurologists are electronic communication and access to knowledge bases. They fulfill needs that are not met by traditional, non‐electronic media. There are many other types of Internet applications that supplement traditional medical methodologies. Finally, some problems and prospects concerning medical uses of the Internet are discussed: technological infrastructure including usability, security, meaning, validity/quality, value, outcomes, and responsibility. These issues must be successfully addressed if Internet computing is to become truly useful ‘just in time’ at the point of medical care. Solutions are actively under development today. The prospects are bright for neurology, and medicine in general, on the Internet. The Internet will become an essential medical device in the near future.
Different postural reaction patterns for expected and unexpected perturbations in patients with idiopathic Parkinson's disease and other parkinsonian syndromes
Authors: Immisch IIka , Bandmann Oliver , Quintern Jochen , Straube Andreas
Published: March 2003

Different postural reaction patterns after predictable and unpredictable perturbations during free stance were studied in 8 patients with idiopathic Parkinson's disease (iPD), in 4 patients with other parkinsonian syndromes (PS) and in 5 healthy controls. First, the amplitude of leaning maximally backward and forward was measured (condition I). Secondly, the body equilibrium was disturbed by self‐paced, predictable, rapid arm elevations (condition II) and by sudden unpredictable toe‐down and toe‐up rotations of a supporting platform (condition III). Patients with PS particularly had difficulties in regaining body equilibrium after unexpected perturbations. In controls and patients with PS, unpredictable disturbances were better compensated in toe‐down than in toe‐up direction, whereas the opposite was true for patients with iPD. These results correspond to the fact that patients with PS had a specific leaning‐backward impairment and patients with iPD, a leaning‐forward impairment. The authors conclude that the differences in postural stability between patients with iPD and PS are caused by different pathophysiological mechanisms. These differences in postural stability could serve as an additional tool for differential diagnosis.
Increased intrathecal nitric oxide formation in multiple sclerosis; cerebrospinal fluid nitrite as activity marker
Authors: Brundin Lou , Morcos Edward , Olsson Tomas , Wiklund N. Peter , Andersson Magnus
Published: March 2003

Nitric oxide is formed from L‐arginine by a family of enzymes: nitric oxide synthase (NOS). The inducible nitric oxide synthase is activated by cytokines and it has been suggested that activation of the enzyme gives rise to neurotoxic levels of reactive nitrogen oxides. This enzyme has been shown to be localized in multiple sclerosis (MS) lesions but the role of nitric oxide formation in the pathogenesis of MS is still unclear. Using capillary electrophoresis, we have analysed nitrite and nitrate in cerebrospinal fluid (CSF) and demonstrate increased levels of reactive nitrogen products in 17 patients with MS. The total levels of oxidized nitrogen products were significantly elevated in MS patients when compared with controls. In patients with active MS, nitrite levels were significantly increased when compared with controls and patients in remission. This is supportive of NOS induction in MS. We suggest that capillary electrophoresis analysis of nitrite and nitrate in CSF could provide a clinically useful way to determine disease activity in MS.
Cerebrospinal fluid filtration in amyotrophic lateral sclerosis
Authors: Finsterer Josef , Mamoli Bruno
Published: March 2003

By means of a randomized, controlled and open study the authors wanted to find out if cerebrospinal (CSF)‐filtration was of substantial benefit to patients with sporadic amyotrophic lateral sclerosis (SALS). Five SALS patients, aged 51–75 years, being treated with riluzole underwent CSF‐filtration daily over five days (group A). Five other SALS patients, aged 52–70 years, were treated only with riluzole (group B). Although all five patients in the first group reported a subjective benefit following CSF‐filtration, the Norris score, the Frenchay score, the vital capacity, the ulnar nerve F‐wave persistence and the peak‐ratio of the brachial biceps and anterior tibial muscles did not change significantly after five days of therapy, either in group A or in group B. In conclusion, filtration of 200–250 ml CSF daily, over five days, does not seem to have a substantial therapeutic effect in patients with SALS.
Adult Leigh syndrome: treatment with intravenous soybean oil for acute central respiratory failure
Authors: Kumagai Rumi , Ichikawa Keiji , Yasui Takashi , Kageyama Yasufumi , Miyabayashi Shigeaki
Published: March 2003

This study reports a 38‐year‐old woman with adult Leigh syndrome associated with partial deficiency of the pyruvate dehydrogenase complex. The patient had intermittent diplopia, loss of vision, dystonia, central respiratory failure and unconsciousness with lactic acidosis. Treatment with an intravenous ketogenic emulsion resulted in rapit clinical and biochemical improvement. In patients with acute respiratory failure under these circumstances, intravenous ketogenic emulsion therapy is worth consideration.
Classification of gait patterns in spastic hemiplegia and spastic diplegia: a basis for a management algorithm
Authors: Rodda J. , Graham H. K.
Published: March 2003

Classifications of gait and postural patterns in spastic hemiplegia and spastic diplegiía are presented, based on the work of previous authors. The classifications are used as a biomechanical basis, linking spasticity, musculoskeletal pathology in the lower limbs, and the appropriate intervention strategies. The choice of target muscles for spasticity management, the muscle contractures requiring lengthening and the choice of orthotics are then linked to the underlying gait pattern.
The measurement of health‐related quality of life (HRQL) in children with cerebral palsy
Authors: Bjornson K. F. , McLaughlin J. F.
Published: March 2003

The measurement of health‐related quality of life (HRQL) in children with cerebral palsy is part of an emerging discipline. Theoretical models of disability and chronic illness developed by the World Health Organization, the National Center for Medical Rehabilitation Research and others are being adapted for children. Development of HRQL measures in paediatrics lags behind the work completed with adults due to challenges unique to children, such as what domains to measure, whose perspective to address and the developmental changes inherent to children. The descriptive HRQL studies of children with moderate to severe cerebral palsy and comparisons of children with quadriplegia vs. diplegia and hemiplegia are presented. Consistent with the functional measures, no significant difference in HRQL by treatment was documented in children with spastic diplegia participating in a randomized clinical trial of selective dorsal rhizotomy. HRQL measures that are specifically tailored to cerebral palsy need to be developed. Generic and individualized measures of HRQL are currently available and while limited, may be useful for evaluating the effect of different treatments for spasticity on the quality of life in children with cerebral palsy.
Diagnosis of motor neuropathy
Authors: Léger J. ‐M. , Salachas F.
Published: March 2003

Motor neuropathy is a clinical entity which leads to consideration of a wide spectrum of peripheral nerve disorders. Firstly, it may be distinguished from other causes of peripheral motor involvement such as muscle diseases and disorders of the neuromuscular junction. Secondly, it may be discussed in two different forms: acute and chronic. Acute chronic neuropathies are mainly observed in Guillain‐Barré syndrome, in which electrophysiological studies allow us to recognize the classical demyelinating form and the axonal form. The other causes of acute motor neuropathy are mainly poliomyelitis and porphyrias. Chronic motor neuropathies are mainly observed in motor neuron diseases, mainly amyotrophic lateral sclerosis, but also Kennedy’s disease and other lower motor neuron diseases which may be inherited or acquired. The other causes are multifocal motor neuropathy and the predominantly motor forms of chronic inflammatory demyelinating polyneuropathy. The characterization of these different types of chronic neuropathy is of major importance because of the therapeutic consequences which may lead to the proposal of specific treatments.
Vinpocetine treatment in acute ischaemic stroke: a pilot single‐blind randomized clinical trial
Authors: Feigin V. L. , Doronin B. M. , Popova T. F. , Gribatcheva E. V. , Tchervov D. V.
Published: March 2003

The aim of the study was to assess the safety and feasibility of a clinical trial on the effect of vinpocetine, a synthetic ethyl ester of apovincamine, in acute ischaemic stroke. Thirty consecutive patients with computed tomography verified diagnosis of acute ischaemic stroke, who could receive drug treatment within 72 h of stroke onset, were enrolled. The patients were randomly allocated to receive either low‐molecular weight dextran alone or in combination with vinpocetine. Poor outcome was defined as being dead or having a Barthel index of < 70 or a Rankin score of 3–5. Intention‐to‐treat analysis was applied. One‐tenth of all hospitalized patients with acute ischaemic stroke were eligible for the trial. Thirty eligible patients were treated with either low‐molecular weight dextran alone (mean age 57.9 ± 11.6 years, n = 15) or in combination with vinpocetine (mean age 60.8 ± 6.6 years, n = 15). The two treatment groups were comparable with respect to major prognostic variables. A relative risk (RR) reduction of poor outcome at 3 months follow‐up was 30% (RR = 0.7; 95% confidence interval [CI] 0.1–3.4), as defined by the modified Barthel Index, and 60% as defined by the modified Ranking score (RR = 0.4, 95% CI: 0.1–1.7). The National Institute of Health (NIH–NINDS) Stroke Scale score was marginally significantly better in the vinpocetine treated group at 3 months of follow‐up (P = 0.05, anova). No significant adverse effects were seen. This pilot study shows that a full‐scale randomized double‐blind, placebo‐controlled trial of vinpocetine treatment in acute ischaemic stroke is feasible and warranted.
Depression is an independent predictor of poor long‐term functional outcome post‐stroke
Authors: Pohjasvaara T. , Vataja R. , Leppävuori A. , Kaste M. , Erkinjuntti T.
Published: March 2003

The influence of depression on the long‐term outcome of stroke patients was examined among 390 of 486 consecutive patients aged 55–85 years. They completed, at 3 months after ischaemic stroke, a detailed medical, neurological, and radiological stroke evaluation, structured measures of emotion (Beck’s Depression Inventory, BDI), handicap (Rankin scale, RS), and assessment of activities of daily living (Barthel Index, BI). Further RS and BI was evaluated at 15‐month follow‐up from these 390 patients and BDI in 276 patients. A group of 256 patients completed, in addition to the 15‐month follow‐up, a comprehensive psychiatric evaluation, including the Present State Examination 3 months after stroke. The DSM‐III‐R criteria were used for diagnosis of the depressive disorders. BDI identified depression (cut‐off point ≥ 10 for depression) in 171 (43.9%) of 390 and in 123 (44.6%) of 276 patients at 3‐ and 15‐month follow‐up. DSM‐III‐R major depression was diagnosed in 66 (25.8%), and minor depression in 32 (12.5%), of 256 patients 3 months after stroke. Patients with BDI ≥ 10, or major, but not minor, depression more often had poor functional outcome (RS > II and BI < 17) at 15 months. Poor functional outcome at 3 months also correlated with depression at 15 months. In logistic regression analysis, depression at 3 months (Beck ≥ 10) correlated with poor functional outcome at 15 months (RS > II) (OR 2.5, 95% CI 1.6–3.8). More careful examination and treatment of depression in stroke patients is emphasized.
Neurorehabilitation: a bridge between basic science and clinical practice
Authors: Kesselring J.
Published: March 2003

A true paradigm shift or revolution of thinking is taking place in the field of neurology. Earlier, it was regarded as the science of exact diagnosis of incurable illnesses, according to the resigned dogma that damage to the central nervous system could not be repaired: “Once development is complete, the sources of growth and regeneration of axons and dendrites are irretrievably lost. In the adult brain the nerve paths are fixed and immutable: everything can die, nothing can be regenerated” (Cajal, 1928). Even then one could have countered this with what holds today: “Rehabilitation does not take place in the test tube!”, and one would have been supported only a short time later by a most authoritative source, if one had read and quoted what the professor of neurology and neurosurgery in Breslau, Otfried Foerster, wrote in a 100‐page article about therapeutic exercises that appeared in the Handbuch der Neurologie. From his introduction, only three sentences are quoted, which illustrate his opinion of the importance of therapeutic exercises and are closer to our views of brain functions today (Foerster, 1936):

There is no doubt that most motor disturbances caused by lesions of the nervous system are more or less completely compensated as a result of a tendency inherent to the organism to carry out as expediently as possible the tasks of which it is capable under normal circumstances, using all the forces still available to it with the remaining undamaged parts of the nervous system, even following injury to its substance. This happens spontaneously, when neither a reversal of the noxa nor a regeneration of the destroyed tissue is possible, simply by means of a reorganization of the remaining parts of the nervous system, which is not a machine composed of individual parts that stands still when one part fails; rather, it possesses an admirable plasticity and exhibits an astonishingly extensive adaptability, not only to changed external conditions but also to disruptions of its own substance. Therapeutic exercises influence the course of spontaneous restoration; they support it, strengthen it. Not infrequently, in fact, they actually set it in motion when the forces essential to restoration lie fallow and are not deployed by the organism.
Increased T cell expression of CD154 (CD40‐ligand) in multiple sclerosis
Authors: Jensen J. , Krakauer M. , Sellebjerg F.
Published: March 2003

CD154 (CD40‐ligand, gp39), expressed on activated T cells, is crucial in T cell‐dependent immune responses and may be involved in the pathogenesis of multiple sclerosis (MS). We studied cerebro‐spinal fluid and peripheral blood T cell expression of CD154 in MS by flow cytometry. Patients with secondary progressive MS (SPMS) had constitutive CD154 expression on CD4 and CD8 T cells in blood. Constitutive CD154 expression was not observed in patients with relapsing‐remitting MS (RRMS) or clinically isolated syndromes (CIS) suggestive of demyelinating disease. After ex vivo activation CD154 was, however, expressed on a higher percentage of T cells from patients with CIS or RRMS than from healthy control subjects. These results suggest involvement of CD154 in the pathogenesis of MS, and the shift from a relapsing‐remitting to a secondary progressive disease course may be associated with constitutive, systemic CD154 expression.
The many faces of crossed aphasia in dextrals: report of nine cases and review of the literature
Authors: Mariën P. , Engelborghs S. , Vignolo L. A. , De Deyn P. P.
Published: March 2003

A substantial body of the aphasia literature has been devoted to the topic of crossed aphasia in dextrals (CAD) over the past century but still no theory exists that explains the anomalous organization of neurocognitive functions in this population. However, if strict selection criteria are applied only some cases of vascular CAD are reported in which the correlation between neurocognitive disturbances and the locus of the brain lesion is studied. This study describes nine new cases of vascular CAD who underwent in‐depth neurolinguistic and neuropsychological investigations. Our analysis shows the semiological variability of CAD phenomena and the many faces of the lesion‐behaviour relationships of this exceptional neurobiological condition.
Impaired benzodiazepine receptor binding in peri‐lesional cortex of patients with symptomatic epilepsies studied by [11C]‐flumazenil PET1
Authors: Szelies B. , Sobesky J. , Pawlik G. , Mielke R. , Bauer B. , Herholz K. , Heiss W.‐D.
Published: March 2003

Individual benzodiazepine receptor (BZR) binding of peri‐lesional cortex was investigated in symptomatic epilepsies. Eleven patients aged 19–44 years were studied whose diagnosis was established by medical history, clinical, electroencephalographic, and magnetic resonance imaging (MRI) findings. Three‐dimensional [11C]‐flumazenil (FMZ) positron emission tomography and MRI scans were obtained and coregistered. Lesions (five low‐grade brain tumours, one AV malformation, one cavernoma, one cystic lesion of unknown aetiology, one traumatic brain injury, one post‐operative and one post‐haemorrhagic defect) were outlined on individual MRI scans. Adjacent to those lesions, and in homologous contralateral structures, FMZ binding was analysed in four pairs of cortical 9 × 9‐mm regions of interest (ROIs) placed on transaxial and coronal slices, respectively, as well as in the lesion volume and its mirror region. Percentage asymmetry ratios were calculated and those at or outside the 90–110% range were operationally defined significant. Peri‐lesional FMZ binding asymmetries ranged from 70 to 125%, lesional asymmetries from 38 to 82%. Only one patient showed no significant change, whilst nine exhibited significant reductions of FMZ binding in at least one ROI (3 × 1, 4 × 2, 1 × 3, 1 × 4), and significant increases were observed in two ROIs of another patient. Therefore, peri‐lesional disturbances of BZR binding are common but variable in location. Because a close correlation between regional decreases in FMZ binding and spiking activity was recently demonstrated in neocortical epilepsies, abnormal peri‐lesional FMZ binding may bear some relation to the mechanisms of epileptogenesis in symptomatic epilepsies.
Subarachnoid haemorrhage associated with infectious endocarditis: case report and literature review
Authors: Chukwudelunzu F. E. , Brown R. D. , Wijdicks E. F. M. , Steckelberg J. M.
Published: March 2003

Cases of subarachnoid haemorrhage (SAH) as a presenting feature or soon after initiation of antibiotics in infectious endocarditis (IE) have been reported. However, most had documented mycotic aneurysms as the source of haemorrhage. Reports of IE associated with SAH of unclear source are rare. A case of SAH associated with IE is reported. We also reviewed our data set on neurological complications of IE at Mayo Clinic Rochester from 1980 to 1996 for additional cases. In addition to the index case, we identified seven cases of SAH amongst 489 patients (1%) with IE for a total of eight cases. In six patients, initial cerebral angiography, magnetic resonance angiography or autopsy did not show aneurysm or other aetiology for the SAH. A mycotic aneurysm was noted in one case and the other patient had an unruptured mycotic aneurysm of the tip of basilar artery. SAH was located in the basal cistern in two patients, sylvian fissure in three, and hemispheric sulci in three. SAH is an uncommon complication of IE, and in the setting of IE a specific cause, such as mycotic aneurysm, may not be identified.
A 6‐year clinical and MRI follow‐up study of patients with relapsing–remitting multiple sclerosis treated with Interferon‐beta
Authors: Paolillo A. , Pozzilli C. , Giugni E. , Tomassini V. , Gasperini C. , Fiorelli M. , Mainero C. , Horsfield M. , Galgani S. , Bastianello S. , Buttinelli C.
Published: March 2003

There are few long‐term clinical and magnetic resonance imaging (MRI) data on patients treated with interferon‐beta (IFN‐β) for relapsing–remitting multiple sclerosis (RRMS). The aim of this study was to provide clinical and MRI data on 68 patients with RRMS treated over a 6‐year period and to investigate whether a baseline MRI predicts their long‐term clinical and MRI outcome. Six MRI scans were performed monthly before treatment and a further 13 scans were performed during treatment with IFN‐β, the last of which 6 years after commencement of treatment. The relapse rate, disability as measured by the Expanded Disability Status Scale (EDSS), and MRI parameters, including Gd‐enhancing lesion load (Gd‐LL), T2 hyperintense lesion load (T2‐LL) T1 hypointense lesion load (T1‐LL) and supratentorial brain volume (SBV) were measured throughout the study. The mean annual relapse rate over the 6 years was 0.52 (SD 0.67), which is significantly lower (68.6%) than the mean annual relapse rate of 1.6 observed during the 2‐year period before the commencement of treatment (P < 0.01). The median EDSS score increased from 2 to 2.5, remaining stable in 60% of the patients. From the baseline scan to the final scan, there was a median increase of 7% in the T2‐LL and 23.9% in the T1‐LL, whilst SBV decreased by 2.7%. The increase in the EDSS over the course of the study was significantly correlated with a reduction in brain volume (r = 0.46, P = 0.001). Greater brain damage at baseline, as measured by both T2‐LL and T1‐LL, was significantly associated with an increase in disability over the 6 years (r = 0.44, P = 0.0009; r = 0.50, P = 0.0007, respectively). This study shows a sustained effect of IFN‐β on the relapse rate, which is lower than during the 2 years before treatment commencement. More than half the patients showed an improvement or stabilization in the EDSS score. The increment in disability was correlated with the development of brain atrophy but not with increases in lesion burden. Finally, the finding that the extent of lesion burden at the baseline was a strong predictor of increasing disability suggests that IFN‐β treatment might have a moderate effect in modifying the multiple sclerosis (MS) disease course over 6 years unless preventive treatment is started early.
Study design validation for consolidating global with focal neurological events in cardiac surgery stroke risk factor analyses
Authors: Boyajian R. A. , Otis S. M. , Tyner J. J. , DeLaria G. A.
Published: March 2003

Neuroimaging shows that both global and focal neurologic deficits after cardiac surgery share an acute, often multifocal, embolic cerebral infarction etiology; yet, analyses of stroke risk factors historically have emphasized the focal deficits. We test if consolidating encephalopathy and coma with focal deficits affects four stroke risk factors and a dummy variable. Overall focal and global events in 575 cardiopulmonary bypass operations identified by retrospective review matched indices reported in large prospective studies. Logistic regression in 189 records selected for completed non‐invasive preoperative carotid stenosis screening showed all four conventional stroke risk factors to be independent predictors of overall consolidated global plus focal neurologic risk, specifically: age [odds ratio (OR) 1.90 per decade], carotid stenosis >50% (OR 1.91), pump time (OR 1.67 per hour), open chamber (OR 1.95); and successfully eliminated the dummy variable gender (P = 0.6). This analysis indicates that the design of future stroke risk factor studies in the setting of cardiac surgery can and should adopt a neuroimaging evidence‐based investigative approach of consolidating global with focal deficits.
Effect of vagal nerve stimulation on patients with bitemporal epilepsy
Authors: Kuba R. , Brázdil M. , Novák Z. , Chrastina J. , Rektor I.
Published: March 2003

Patients with bitemporal epilepsy are characterized by the existence of independent bitemporal seizure onset zones. The aim of this study was to evaluate the effect of chronic vagal nerve stimulation (VNS) on eight patients with bitemporal epilepsy. We demonstrated the gradually increased effect of VNS on the reduction of seizures as compared with baseline seizure frequency in patients with bitemporal epilepsy. The average seizure reduction increased from 4.2% at the 3‐month follow‐up visit to 18.2, 34.4 and 42.2% at the 6, 12 and 18‐month follow‐up visits. Similarly, a ≥50% reduction of complex partial seizures was reported at the 3‐month follow‐up visit in no patients (0%); at the 6‐month follow‐up visit in one patient (12.5%); at the 12‐month follow‐up visit in three patients (37.5%); and at the 18‐month follow‐up visit in five patients (62.5%). These data demonstrate the positive and long‐lasting effect of VNS on seizure reduction in patients with intractable bitemporal epilepsy. The main mechanism of this chronic effect is not fully understood.
CSF tau protein andβ‐amyloid (1–42) in Alzheimer's disease diagnosis: discrimination from normal ageing and other dementias in the Greek population
Authors: Kapaki E. , Paraskevas G. P. , Zalonis I. , Zournas C.
Published: March 2003

Cerebrospinal fluid (CSF) levels of tau protein and amyloidβ(1–42) peptide (Aβ42) have been suggested as possible diagnostic markers of Alzheimer's disease (AD). In order to evaluate their diagnostic potential in clinical practice, we measured tau and Aβ42 levels in the CSF of 49 AD patients, 15 patients with non‐AD neurodegenerative dementias (NAND), six patients with vascular dementia (VD) and 49 elderly controls. All the subjects were of Greek origin. A marked increase in tau, a decrease in Aβ42 and a marked increase in the tau/Aβ42 ratio was noted in AD. Aβ42 alone had a specificity of 80% and a sensitivity of 82% in differentiating AD from normal ageing, whilst the corresponding values for differentiating AD from NAND or VD were 80 and 71, or 67 and 82%, respectively. Tau was better in differentiating AD, from normal ageing (specificity 96%, sensitivity 88%), NAND (specificity 93%, sensitivity 71%) and VD (specificity 83%, sensitivity 94%). The tau/Aβ42 ratio achieved values comparable or even better than tau for differentiating AD from normal ageing (specificity 86%, sensitivity 96%) and VD (specificity 83%, sensitivity 90%) and definitely better than any of the candidate markers alone, for differentiating AD from NAND (specificity 100%, sensitivity 71%). Thus, the combined use of CSF tau and Aβ42 in the form of the tau/Aβ42 ratio is a simple, safe and useful adjuvant to clinical criteria for dementia diagnosis.
Cerebral Hemodynamics in Familial Hemiplegic Migraine
Authors: Jensen T. Staehelin , Voldby B. , Olivarius B. de Fine , Jensen F. Tågehøj
Published: March 2003

Clinical findings of four female members from one family with familial hemiplegic migraine are briefly summarized. Cerebral blood flow (CBF) studies using the xenon 133 inhalation method were carried out during and between hemiplegic attacks in two of the family members. CBF was significantly lower over the affected hemisphere during attacks, while equal flow on both sides was seen in headache free periods. The findings indicate that cerebral perfusion is altered, but not necessarily decreased during attacks of familial hemiplegic migraine.
Extracranial Vascular Reactivity in Migraine and Tension Headache
Authors: Drummond Peter D. , Lance James W.
Published: March 2003

The amplitude of temporal artery pulsation was monitored at rest, after standing from the sitting position and after exercise in 23 normal controls, 10 patients subject to chronic tension headache and 107 migrainous patients. The pulses of migrainous patients did not differ from normal at rest or on standing. On exercise, the temporal artery on the habitually affected side of migrainous patients dilated more than the headache-free side, while exercise-induced changes in tension headache patients were less than those in normal controls. The responses were not influenced by previous or current medication.
Cluster Headache in Women: Evidence of Hypofertility(?) Headaches in Relation to Menstruation and Pregnancy
Authors: Ekbom Karl , Waldenlind Elisabet
Published: March 2003

Two hundred and forty-nine patients with cluster headache have been studied, 215 male and 34 female (ratio 6.3:1). Twenty-five of the 26 fertile female cluster patients stated that their headaches had no relation to menstrual periods. Eight had had 13 pregnancies since the onset of cluster headache. Six of them experienced remission of their headache during pregnancy. Four women with cluster headache had a history of infertility or premature menopause. Parity rate was low in patients who contracted cluster headache as nulliparae; it was lower than in those who contracted the disease after earlier pregnancy or post menopause, and also significantly lower than in 99 consecutive women with migraine. Significant differences were also found when the numbers of childbirths in the cluster patients were compared with total fertility rates up to successive ages for birth cohorts in the general population of Swedish women ( p < 0.01).
Comparison of the Contraction Produced by Various Tryptamine Analogues on Human Basilar Arterial and Rat Aortic Strips In Vitro
Authors: Forster Christine , Whalley E. T.
Published: March 2003

The effect of various closely related analogues of 5-hydroxytryptamine were studied on the human basilar arterial and rat aortic strips in vitro. All analogues (except 5-methoxytryptamine) contracted both preparations producing maximal responses equivalent to that obtained with 5-hydroxytryptamine. Maximum responses to 5-methoxytryptamine were equivalent to and only 60% of the maximum obtained with 5-hydroxytryptamine on human basilar artery and rat aorta, respectively. The order of potency of the analogues on the human basilar artery was different from that obtained on the rat aorta. 5-methyltryptamine, N-methyltryptamine and tryptamine were equipotent on both tissues, whereas 5-hydroxytryptamine and 5-methoxytryptamine were 229 and 296 times more potent, respectively, on the human basilar artery compared to the rat aorta. Both tissues appear to be deficient in monoamine oxidase, since nialamide or iproniazid did not potentiate responses to tryptamine. It is concluded that the receptor type mediating contraction of the human basilar artery to 5-hydroxytryptamine is different from the classical smooth muscle D-receptor.
Cluster Headache. The Sweating Pattern During Spontaneous Attacks
Authors: Sjaastad Ottar , Saunte Carsten , Russell David , Hestnes Arnulf , Mårvik Ronald
Published: March 2003

Sweating in the forehead, on the eyelids, in the face and on the trunk was measured with the Evaporimeter during 31 spontaneous cluster headache attacks of varying severity in 18 patients, the evaporimeter measures evaporative water loss (sweating + transepidermal water loss) rapidly and accurately as g/m2/h. The patients themselves acted as controls. Sweating was also estimated in 25 healthy individuals at a temperature of 27 ± 1 C, and a mean relative humidity of 19%. During eight severe attacks, sweating in the medial part of the forehead on the symptomatic side was invariably increased. In moderate attacks the increment was less pronounced and in the inter-cycle period, no definite increase was found. The cause: of increased sweating during cluster headache attacks remains enigmatic. Cluster headache sweating, sympathetic nervous system.
Psychophysiological Response Patterns in Migraine Patients
Authors: Ellertsen Bjørn , Hammerborg Dag
Published: March 2003

Cardiovascular responses to strong auditory stimulation were compared in common migraine patients and controls. Two matched groups of eight subjects participated in two laboratory sessions. During each session, baseline recording of the cardiovascular variables was followed by twenty auditory stimuli (95 dB, 1000 Hz), sounded at irregular intervals. Phasic responses in heart rate and pulse wave amplitudes in the superficial temporal arteries were measured. A post stimulation sampling period ended each session. Different cardiovascular response patterns were found in the two groups. The migraine patients showed more pronounced heart rate responses and slower habituation to stimulation. Stronger pulse wave amplitude reduction during stimulation and an increase during the post stimulation period was also found in the migraine group.
Common Migraine Attacks Preceded by Focal Hyperemia and Parietal Oligemia in the rCBF Pattern
Authors: Gelmers H. J.
Published: March 2003

Regional cerebral blood flow (rCBF) was measured in the dominant hemisphere with the xenon-133 injection method, using the 254 multidetector gamma camera. Two patients developed a common migraine attack during the rCBF studies. The headache was preceded by focal oligemia in the occipitoparietal region in one of the patients and in the parietocentral region in the other. Neurological examination was normal. These results indicate that the initiating cerebral hemodynamics in common migraine are, at least in particular patients, the same as in patients with classic migraine.
β-Adrenoceptor Blockade and Migraine
Authors: Weerasuriya K. , Patel L. , Turner P.
Published: March 2003

Except for propranolol, no other b-blocker has been studied thoroughly in the prophylaxis of migraine. Of those studied, propranolol, atenolol and timolol were shown to be useful in double-blind clinical trials. The mode, or even the site of action of these drugs is unknown. Possible mechanisms of action are peripheral vascular effects, a central action, 5-HT antagonism, an anxiolytic effect and a multifactorial action. The only common property of the successful drugs is lack of partial agonist activity and their profiles do not fully support any of the above hypotheses. Trials of drugs in the prophylaxis of migraine have in general been unsatisfactory due to the difficulty in controlling many variables. b-blockers with differing properties offer an opportunity to define the properties necessary for anti-migraine activity and perhaps shed light on the pathogenesis of migraine.
Headache Patients: Different Responses Induced by Naloxone During Work-Test
Authors: Steardo Luca , Barone Paolo , Stasio Emanuela di , Bonuso Salvatore
Published: March 2003

The responses to work-test in ischemia (tourniquet technique), before and after I.V. injection of naloxone (2 mg) or saline, were investigated in healthy volunteers and patients suffering from various types of headache. The patients were examined during both painful and painless periods. We found that only the subjects suffering from migraine showed a significantly shortened pain tolerance at work-test in ischemia, after injection of naloxone, and only during painful periods. Psychogenic headache patients and migraine patients in painless periods showed responses during work-test similar to those in healthy volunteers, even after injection of naloxone. We believe that hyperalgesic effect of naloxone is due to involvement of b-endorphin systems only during organic pain.
Tolfenamic Acid and Caffeine: A Useful Combination in Migraine
Authors: Hakkarainen H. , Parantainen J. , Gothoni G. , Vapaatalo H.
Published: March 2003

Tolfenamic acid is a potent inhibitor of prostaglandin biosynthesis, which has been proved effective in the treatment of acute migraine attacks. The usefulness of caffeine, metoclopramide and pyridoxine as adjuncts to tolfenamic acid was tested in acute migraine attacks in ten patients. A combination of tolfenamic acid (200 mg) with either caffeine (100 mg), metoclopramide (10 mg) or pyridoxine (300 mg) was given twice to each patient in random order. Thus 60 attacks were treated. The tolfenamic acid-caffeine combination proved the most effective as judged by duration and intensity of attacks, working ability, vigilance, and overall evaluation of the drugs by the patients. Metoclopramide was somewhat better than pyridoxine as an additive.
Migraine in Children: A Medical and Psychiatric Study
Authors: Marates Jason , Wilkinson Marcia
Published: March 2003

Forty-seven migrainous children were examined medically, neurologically and psychiatrically and compared with matched controls from a dental clinic. One in six children suffered from more than one type of migraine. There was a wide variation in age of onset and the frequency and duration of attacks varied considerably. An “emotional upset” was the most frequently reported (86%) precipitating factor. Most children responded to simple therapeutic measures and detailed instructions about the timely use of medication. A significantly higher proportion of migrainous children than their controls showed signs of a neurotic disorder (mainly anxiety or depression) and had had a higher prevalence of neurotic disorder in the previous year. This increased prevalence was found to be associated with a disturbed parental relationship and certain factors related to their mothers (age, “malaise” score). A prospective study of an epidemiological sample based on systematic observation rather than recollections and opinions is likely to yield more conclusive results.