bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evoked potentials from direct cerebellar stimulation for monitoring of the rodent spinal cord
Authors: Hurlbert R. John , Tator Charles H. , Fehlings Michael G. , Niznik Greg , Linden R. Dean 
Published: May 2009

✓ Although the assessment of spinal cord function by electrophysiological techniques has become important in both clinical and research environments, current monitoring methods do not completely evaluate all tracts in the spinal cord. Somatosensory and motor evoked potentials primarily reflect dorsal column and pyramidal tract integrity, respectively, but do not directly assess the status of the ventral funiculus. The present study was undertaken to evaluate the use of evoked potentials, elicited by direct cerebellar stimulation, in monitoring the ventral component of the rodent spinal cord. Twenty-nine rats underwent epidural anodal stimulation directly over the cerebellar cortex, with recording of evoked responses from the lower thoracic spinal cord, both sciatic nerves, and/or both gastrocnemius muscles. Stimulation parameters were varied to establish normative characteristics. The pathways conducting these “posterior fossa evoked potentials” were determined after creation of various lesions of the cervical spinal cord.
The evoked potential recorded from the thoracic spinal cord consisted of five positive (P1 to P5) and five negative (N1 to N5) peaks. The average conduction velocity (± standard deviation) of the earliest wave (P1) was 53 ± 4 m/sec, with a latency of 1.24 ± 0.10 msec. The other components followed within 4 msec from stimulus onset. Unilateral cerebellar stimulation resulted in bilateral sciatic nerve and gastrocnemius muscle responses; there were no significant differences (p > 0.05) in the thresholds, amplitudes, or latencies of these responses elicited by right- versus left-sided stimulation. Recordings performed following creation of selective lesions of the cervical cord indicated that the thoracic response was carried primarily in the ventral funiculus while the sciatic and gastrocnemius responses were mediated through the dorsal half of the spinal cord. It is concluded that the posterior fossa evoked potential has research value as a method of monitoring pathways within the ventral spinal cord of the rat, and should be useful in the study of spinal cord injury.
Effect of AT877 on cerebral vasospasm after aneurysmal subarachnoid hemorrhage
Authors: Shibuya Masato , Suzuki Yoshio , Sugita Kenichiro , Saito Isamu , Sasaki Tomio , Takakura Kintomo , Nagata Izumi , Kikuchi Haruhiko , Takemae Toshiki , Hidaka Hiroyoshi , Nakashima Mitsuyoshi 
Published: May 2009

✓ With the cooperation of 60 neurosurgical centers in Japan, a prospective randomized placebo-controlled double-blind trial of a new calcium antagonist AT877 (hexahydro-1-(5-isoquinolinesulfonyl)-1H-1,4-diazepine hydrochloride, or fasudil hydrochloride) was undertaken to determine the drug's effect on delayed cerebral vasospasm in patients with a ruptured cerebral aneurysm. A total of 276 patients, who underwent surgery within 3 days after subarachnoid hemorrhage (SAH) of Hunt and Hess Grades I to IV, were entered into the study. Nine patients were excluded because of protocol violation. The remaining 267 patients received either 30 mg AT877 or a placebo (saline) by intravenous injection over 30 minutes, three times a day for 14 days following surgery. Demographic and clinical data were well matched between the two groups.
It was found that AT877 reduced angiographically demonstrable vasospasm by 38% (from 61% in the placebo group to 38% in the AT877 group, p = 0.0023), low-density regions on computerized tomography associated with vasospasm by 58% (from 38% to 16%, p = 0.0013), and symptomatic vasospasm by 30% (from 50% to 35%, p = 0.0247). Furthermore, AT877 reduced the number of patients with a poor clinical outcome associated with vasospasm (moderate disability or worse on the Glasgow Outcome Scale at 1 month after SAH) by 54% (from 26% to 12%, p = 0.0152). There were no serious adverse events reported in the AT877 group. This is the first report of a placebo-controlled double-blind trial that has demonstrated a significant reduction in angiographically revealed vasospasm by intravenous drug therapy.
Pathophysiology and treatment of focal cerebral ischemia
Authors: Siesjö Bo K. 
Published: May 2009

✓ This article examines the pathophysiology of lesions caused by focal cerebral ischemia. Ischemia due to middle cerebral artery occlusion encompasses a densely ischemic focus and a less densely ischemic penumbral zone. Cells in the focus are usually doomed unless reperfusion is quickly instituted. In contrast, although the penumbra contains cells “at risk.” these may remain viable for at least 4 to 8 hours. Cells in the penumbra may be salvaged by reperfusion or by drugs that prevent an extension of the infarction into the penumbral zone. Factors responsible for such an extension probably include acidosis, edema, K+/Ca++transients, and inhibition of protein synthesis.Central to any discussion of the pathophysiology of ischemic lesions is energy depletion. This is because failure to maintain cellular adenosine triphosphate (ATP) levels leads to degradation of macromolecules of key importance to membrane and cytoskeletal integrity, to loss of ion homeostasis, involving cellular accumulation of Ca++, Na+, and Cl−, with osmotically obligated water, and to production of metabolic acids with a resulting decrease in intra- and extracellular pH.In all probability, loss of cellular calcium homeostasis plays an important role in the pathogenesis of ischemic cell damage. The resulting rise in the free cytosolic intracellular calcium concentration (Ca++) depends on both the loss of calcium pump function (due to ATP depletion), and the rise in membrane permeability to calcium. In ischemia, calcium influx occurs via multiple pathways. Some of the most important routes depend on activation of receptors by glutamate and associated excitatory amino acids released from depolarized presynaptic endings. However, ischemia also interferes with the intracellular sequestration and binding of calcium, thereby contributing to the rise in intracellular Ca++.A second key event in the ischemic tissue is activation of anaerobic glucolysis. The main reason for this activation is inhibition of mitochondrial metabolism by lack of oxygen; however, other factors probably contribute. For example, there is a complex interplay between loss of cellular calcium homeostasis and acidosis. On the one hand, a rise in intracellular Ca++is apt to cause mitochondrial accumulation of calcium. This must interfere with ATP production and enhance anaerobic glucolysis. On the other hand, acidosis must interfere with calcium binding, thereby contributing to the rise in intracellular Ca++.
Long-term evaluation of decompressive surgery for degenerative lumbar stenosis
Authors: Caputy Anthony J. , Luessenhop Alfred J. 
Published: May 2009

✓ One-hundred patients who had undergone decompressive surgery for lumbar stenosis between 1980 and 1985 were evaluated as to their long-term outcome. Four patients with postfusion stenosis were included. A 5-year follow-up period was achieved in 88 patients. The mean age was 67 years, and 80% were over 60 years of age. There was a high incidence of coexisting medical diseases, but the principal disability was lumbar stenosis with neurological involvement. Results were categorized as either a surgical success or a failure. depending upon the achievement of preset goals within the context of lifestyle and needs. There were no perioperative complications.Initially there was a high incidence of success, but recurrence of neurological involvement and persistence of low-back pain led to an increasing number of failures. By 5 years this number had reached 27% of the available population pool, suggesting that the failure rate could reach 50% within the projected life expectancies of most patients. Of the 26 failures, 16 were secondary to renewed neurological involvement, which occurred at new levels of stenosis in eight and recurrence of stenosis at operative levels in eight. Reoperation was successful in 12 of these 16 patients, but two required a third operation.The incidence of spondylolisthesis at 5 years was higher in the surgical failures (12 of 26 patients) than in the surgical successes (16 of 64). Spondylolisthetic stenosis tended to recur within a few years following decompression. To forestall recurrences, it is suggested that stabilization be carried out at levels of spondylolisthetic stenosis and the initial decompression include adjacent levels of threatening symptomatic stenosis. However, the heterogenicity of this patient population, with varying patterns and levels of symptomatic stenosis, precludes application of rigid surgical protocols.
Cell-mediated immunity in severely head-injured patients: the role of suppressor lymphocytes and serum factors
Authors: Quattrocchi Keith B. , Miller Claramae H. , Wagner Franklin C. , DeNardo Sally J. , DeNardo Gerald L. , Ovodov Konstantin , Frank Edmund H. 
Published: May 2009

✓ Severe head injury results in suppression of cellular immunity associated with defectivein vitrofunctioning of effector lymphocytes, such as helper T cells and cytotoxic T cells. It is not known whether this suppression in effector lymphocyte function is due to intrinsic lymphocyte dysfunction, to suppressor peripheral blood mononuclear cells (PBMC's) such as suppressor lymphocytes or suppressor monocytes, or to serum factors capable of inhibiting effector lymphocyte function. The purpose of this study was to determine whether a subpopulation of PBMC's and/or serum factors) are responsible for this observed suppression in cell-mediated immunity.Cell-mediated immune activity was determined measuringin vitrolymphokine-activated killer (LAK) cytotoxicity following incubation of PBMC's from 15 head-injured patients with those from 15 heterologous normal subjects. The PBMC's were separated into lymphocyte-enriched and monocyte-enriched subpopulations by plastic adherence techniques, and the effect of each population on LAK cytotoxicity was determined. Additionally, the effect on cytotoxicity of serum from the head-injured patients was determined in a dose-response fashion.There was significant depression in LAK cytotoxicity when: 1) PBMC's from normal subjects were incubated with PBMC's from head-injured patients (p < 0.001); 2) lymphocytes (PBMC's depleted of monocytes) from head-injured patients were incubated with PBMC's from normal subjects (p < 0.001); and 3) PBMC's from normal subjects were incubated with serum from head-injured patients (p < 0.001). No suppression in cellular immunity was noted when lymphocytes from normal subjects were incubated with monocytes from head-injured patients.The results indicate that lymphocytes rather than monocytes actively inhibit cellular immunity following severe head injury. The detection of immmunosuppressive serum factors suggests a mechanism by which lymphocytes might be modulated by severe head injury.
Experimental repair of the oculomotor nerve: the anatomical paradigms of functional regeneration
Authors: Pallini Roberto , Fernandez Eduardo , Lauretti Liverana , Draicchio Francesco , Pettorossi Vito E. , Gangitano Carlo , Del Fà Aurora , Olivieri-Sangiacomo Corrado , Sbriccoli Alessandro 
Published: May 2009

✓ In adult guinea pigs, the oculomotor nerve was sectioned proximally (at the tentorial edge) or more distally (at the orbital fissure) and immediately repaired by reapproximation. During a 24-week postoperative period, extrinsic eye motility was assessed by analyzing the vestibulo-ocular reflexes. The regenerated oculomotor nerve was studied morphometrically on semi-thin histological sections at 16 and 24 weeks postinjury. The selectivity of muscle reinnervation was investigated by injection of both single (horseradish peroxidase) and double (fluorescent dyes) retrograde axonal tracers into the eye muscles. Following proximal repair of the oculomotor nerve, the degree of recovery of extraocular motility varied among different animals and remained stable over long-term observations. In animals with poor recovery, aberrant eye movements were always found, and the somatotopic map of the reinnervated eye muscles was greatly altered. Distortions of the central representation were also seen in those animals in which a good level of functional recovery was seen. However, in animals with good recovery, a topographic bias was re-established by about 65% of the original neuronal population, as opposed to 26% in the animals with poor recovery. Neurons located contralateral to the axotomized nucleus sprouted intra-axially and projected their axons to denervated eye muscles. The number and diameter of the regenerated axons, the number and soma diameter of the axotomized neurons, and the ratio of distal axonal branches to proximal supporting neurons were all related to the degree of functional recovery.
Following repair of the oculomotor nerve at the orbital fissure, extraocular motility had recovered in all of the animals at 16 weeks without aberrant phenomena. Functional regeneration of the distally transected oculomotor nerve is thought to be the result of selective muscle reinnervation.
Seabird metapopulations: searching for alternative breeding habitats
Authors: Schippers Peter , Snep Robbert P. H. , Schotman Alex G. M. , Jochem René , Stienen Eric W. M. , Slim Pieter A. 
Published: May 2009

AbstractToday, many seabird species nest in port areas, which are also necessary for human economic activity. In this paper, we evaluate, using a metapopulation model, the possibilities for creating alternative breeding sites for the Common Tern (Sterna hirundo) in the Rhine–Meuse–Scheldt estuary. We explore 22 scenarios that differ with respect to (1) loss of breeding habitat in port areas, (2) location and size of newly created habitat, and (3) coexistence of old and new habitat. Results indicate that loss of port area habitats results in a serious 41% decline in the breeding population. When the loss in ports is compensated for within the ports, the decline was negligible. Fourteen scenarios result in an increase of the Common Tern metapopulation. In these, extra breeding habitat is created outside the ports in fish‐rich waters, resulting in a potential metapopulation increase of 25%. However, the period of overlap between lost and newly created habitat strongly affects the results. A gap between the removal of old and the creation of new breeding areas might cause a drop in the metapopulation level of 30%. The population recovery from this drop might take more than 100 years due to slow recolonization. Our results suggest that conservation of seabird species should be evaluated on a metapopulation scale and that the creation of new habitat may help to compensate for habitat loss in other areas. Furthermore, the results indicate that overlap between the existence of old and newly created breeding habitats is crucial for the success of compensation efforts. However, new locations should be carefully selected, because not only is the suitability of the breeding grounds important, but ample fish availability nearby is also key.
Lipoma of Guyon’s canal causing ulnar neuropathy
Authors: Rohilla Seema , Yadav Rohtas K. , Dhaulakhandi Dhara B. 
Published: May 2009

AbstractLipoma is a benign soft tissue tumor which rarely causes neuropathy. In closed compartments such as Guyon’s canal, even small volume loss can lead to compression of nerve. Hence in such areas, even innocuous tumors such as lipomas can cause neuropathy and warrant surgery. We present one such case of ulnar neuropathy caused by lipoma of Guyon’s canal.
Effects of landscape and demographic history on genetic variation in Picea glehnii at the regional scale
Authors: Goto Susumu , Tsuda Yoshiaki , Koike Yukihiro , Lian Chunlan , Ide Yuji 
Published: May 2009

AbstractTo evaluate the effects of landscape and demographic history on genetic variation in Picea glehnii at a regional scale we have investigated the genetic diversity and genetic differentiation of P. glehnii populations in the Furano region, central Hokkaido, Japan, using seven simple sequence repeat (SSR) markers. We found significant correlations between elevation and genetic diversity parameters. The value of A[46] increased and the value of FIS decreased with increasing elevation, while FIS values were not significantly different from 0 in any of the populations. Significant recent bottlenecks were detected for isolated populations at low‐elevation sites and for relatively large populations at moderate‐ and high‐elevation sites. Evolutionary events pre‐dating the Holocene should be taken into consideration, as elevational gradients should be with respect to locally adapted traits such as flowering phenology, However, the palynological data from the Holocene in this region suggest that the distribution pattern of genetic diversity of P. glehnii detected here may have been influenced by past demographic history related to the elevation shifts in this species’ distribution associated with climate change during this period. Population differentiation was low, with FST and G′ST values of 0.022 and 0.065, respectively. However, genetic boundaries were detected around one swamp population (C13). Therefore, significant isolation by distance (IBD) was not detected when all populations were considered, but there was significant IBD when the C13 population was excluded. Information on genetic diversity and genetic differentiation at the regional scale may be useful for selecting seed sources for afforestation programs for P. glehnii.
Relationships between bird‐dispersed plants and avian fruit consumers with different feeding strategies in Japan
Authors: Yoshikawa Tetsuro , Isagi Yuji , Kikuzawa Kihachiro 
Published: May 2009

AbstractWe examined the interactions between bird‐dispersed plants and fruit‐consuming birds with various feeding strategies, by reviewing the plant species consumed by 14 bird species in Japan with four feeding types: gulpers (five species), grinders (four species), crushers (four species), and peckers (one species). Our literature review provided information on the plant species consumed by the birds in Japan and the morphological traits of the fruits: fruit volume, seed mass and number, pulp type (fleshy, dry, or arillate), and plant height (tall, medium, or small). Using these data, we examined the diversity of plant species consumed by each bird and the fruit morphological traits that affected fruit selection. The five gulpers consumed fruits from the largest number of plants, followed by the four grinders, the four crushers, and the one pecker. The gulpers and grinders consumed a wider variety of fruits than were consumed by the crushers and the pecker. Logistic regression analysis revealed that some crushers and the pecker preferred plants with dry or arillate pulp around the seeds. Our results suggest that a frugivorous bird's feeding strategies, and particularly its fruit‐handling behaviors and the fruit parts it ingests, influence the diversity of plants it consumes. The crushers and the pecker, which feed exclusively on seeds, require more effort and time to consume this type of food, and this might cause a strong preference for specific fruit traits and thus, consumption of a lower diversity of plant species.
Pediatric femur neck fractures: A retrospective analysis of 39 hips
Authors: İnan Ulukan , Köse Nusret , Õmeroğlu Hakan 
Published: May 2009

Purpose The aim of this retrospective study was to analyze the radiological and clinical results of pediatric femur neck fractures. Methods This study included 39 children (mean age 11.1, range 4 to 16 years) who had a femur neck fracture and had at least one year of complete follow-up. The most common etiological factor was traffic accident and the most common associated skeletal injury was pelvis fracture. Results According to Delbet's classification system, there were no type I (transepiphyseal) fractures and 21 type II (transcervical), 14 type III (cervicotrochanteric), and four type IV (intertrochanteric) fractures. The mean follow-up was 3.4 (1–9.5) years. A satisfactory outcome according to Ratliff's radiological and clinical criteria was obtained in 28 (72%) hips. Avascular necrosis (AVN) of the femoral head was seen in 11 (28%) hips and the rate of satisfactory outcome was significantly higher in hips without AVN than in hips with AVN ( P < 0.001). Transcervical fractures had the worst outcome ( P = 0.014) and the highest rate of AVN ( P = 0.077) when compared with cervicotrochanteric and intertrochanteric fractures. No significant correlation was found between both the outcome and development of AVN and age, gender, laterality, amount of fracture displacement, treatment time, and the type of reduction (open/closed) ( P > 0.05). Conclusions It has been concluded that the development of AVN primarily influences the outcome in pediatric femur neck fractures and that fracture type is essentially correlated with the development of AVN and outcome.
Failed vascularized proximal fibular epiphyseal transfer for hip reconstruction following infection in children
Authors: Debarge Romain , Chotel Franck , Gazarian Aram , Viola Jérémy , Berard Jérôme 
Published: May 2009

Purpose Treatment of the sequellae of hip infection with epiphyseal destruction in children has had limited success to date. The aim of this study was to report mid-term results after hip epiphyseal reconstruction using a proximal vascularized fibular graft in three children presenting with massive epiphyseal destruction of the proximal femur following infection. Methods Three children suffered from hip articular destruction type IVB according to the Choi classification after neonatal septic arthritis. The mean age at reconstruction was 4.3 years (range 3–6 years). The Hunka et al. criteria were used to evaluate the functional results, and the clinical evaluation was based on the Musculo-Skeletal Tumor Society (MSTS) score. Growth and fusion of the graft and hip morphology were evaluated on simple X-rays and by magnetic resonance imaging (MRI). A ratio between cephalic diameter and inter-acetabular gap was defined on the MRI scan as the “acetabular filling index”. Results No intraoperative complication was reported. With a mean follow-up of 4.8 years (3–6 years), the MSTS score was 22.7/30 (range 20–26), while the average lower limb length discrepancy was 3 cm. Patient 1 required a secondary derotation osteotomy of the femur because of abnormal external rotation and a bad result due to the unexplained occurrence of a painful and stiff hip joint. A secondary distal transfer of the greater trochanter was performed in patient 2, and good results based on Hunka et al.'s criteria were achieved. The X-rays of patients 1 and 2 showed signs of bone growth and a major remodeling process; the MRI filling indices were 83 and 67%, respectively. Patient 3 developed an early slipped capital (fibular) epiphysis 1 month postoperatively, which was treated by percutaneous pinning; this early complication led to a bad result with full resorption of the graft. Conclusions In contrast to its success in upper limb reconstruction, in this series of three patients with hip articular destruction, articular reconstruction using a vascularized proximal fibula graft was disappointing and led to unsatisfactory results in terms of hip reconstruction. Such a procedure is complex and highly demanding, necessitating extremely intensive post-operative care. An early slipped capital epiphysis can lead to full graft resorption. Consequently, despite important adaptation and remodeling of the graft, the authors do not recommend this procedure at this location.